CN100440748C - Systems and methods for interrogating and playing implantable medical device information - Google Patents

Abstract

Disclosed is the transmission of implantable medical device (IMD) information, including programmed parameter values, interrogation of operating modes and operating conditions, confirmation of programmed changes thereof, stored in the IMD, by radio frequency transmission of audible sounds produced by the IMD. Methods and apparatus for interrogation of data in, and patient alerts or other messages. IMDs include radio frequency transmitters that play or emit audible sounds, including voiced statements or musical tones stored in analog memory associated with programming or interrogating operating algorithms or alerting trigger events. Broadcast radio signals are received by a radio receiver, audible sounds are demodulated and reproduced as voiced statements or musical tones conveying human intelligible messages, including IMD messages generated during programming or interrogation sessions and alerts to the patient at other times or status messages.

Description

Systems and methods for interrogating and playing implantable medical device information

technical field

The present invention generally relates to improved methods and apparatus for providing transmission of implantable medical device (IMD) information during IMD interrogation via broadcast radio signals capable of being received and reproduced as human intelligible voiced statements or other audible sounds.

Background technique

Early IMDs, such as implantable cardiac pacemakers, were designed to generally operate in a single mode of operation, controlled by fixed operating parameters, without the ability to change modes of operation or otherwise communicate through the skin with external devices. It is evident that some day it will be clinically desirable to alter certain operating parameters and/or operating modes. The initial approach to implantable pacemakers involved the use of a tiny rheostat that could be directly accessed by inserting a needle-like tool through the patient's skin to adjust the resistance in the pacing rate or pulse width setting circuit. Later, a tiny reed switch was incorporated into the pacing rate or pulse width circuit, which responded to a magnetic field applied through the skin by an external magnet placed at the implant site. In this way pulse width, pacing rate and a limited number of pacing modes can be adjusted.

Observation of the operation of an implantable cardiac pacemaker can also be achieved, for example, by using a standard EKG machine and by the time interval between pacing pulse spikes in an ECG trace recorded from the patient's skin electrodes. The reed switch is closed using the applied magnet to change the pacing mode to an asynchronous pacing mode and translate the fixed pacing rate or pulse amplitude or width to a value reflecting the current operating parameters. One application of this technique is monitoring impending battery depletion by observing the change in pacing rate based on the voltage drop of the battery from a preset or programmed pacing rate, eg, as described in US Patent 4,445,512. Of course, this approach can only provide a low-bandpass data channel to avoid interfering with the primary function of pacing the patient's heart if necessary.

Furthermore, when the radio antenna is placed over the implant lead, the pacing pulses conducted through the elongated pacing lead conductors cause the electromagnetic signal to be heard as noise pulses on the AM radio frequency band. Thus, delivery of pacing pulses can be confirmed without an EKG machine, and pacing rate can be roughly determined by timing successive noise pulses with a stopwatch. Incorporating an output circuit sensor into certain models of pacemakers causes the sensor to "ring" when a pacing pulse is delivered for the entire duration of the pacing pulse. The duration of the noise pulse picked up by the radio is proportional to the pacing pulse width, and it is at least theoretically possible to measure the pacing pulse width from the duration of the noise pulse.

It can be understood that with the development of digital circuit technology, control of the operating modes and parameters of implanted medical devices can be implemented in digital or binary circuits using stored control states or operating parameter values. To change an operating mode or parameter value, "programmers" were developed based on radio frequency (RF) downlink data communication from an external programmer transceiver to a telemetry transceiver and memory built into the IMD.

By using this telemetry system, it is possible to provide uplink data telemetry to send the contents of registers or memory within the IMD to a telemetry receiver within the programmer using the same RF transmission capability. Today, both analog and digital data can be sent from an implanted medical device to an external programmer via uplink RF telemetry. In the context of implantable cardiac pacemakers, analog data typically includes battery status, sampled ECG amplitude values, sensor output signals, pacing pulse amplitude, energy and pulse width, and pacing lead impedance. Digital data typically includes statistics on performance, event flags, current values of programmable parameters, implant data, and patient and IMD identification codes.

生产线上把RF载波频率设置成175kHz，而且IMD的RF遥测术天线一般是置于密封外壳内的绕在铁氧体芯上的导线线圈。使外部编程器的RF遥测术天线包含于一编程头以及可以置于IMD之上病人皮肤上的永磁铁，以便在IMD的密封外壳内建立磁场。The evolution to the current commonly used telemetry transmission system depends on the formation of a low amplitude magnetic field in the transmit mode by current oscillations in the RF telemetry antenna LC circuit and the detection of induced currents in the receive mode RF telemetry antenna located in close proximity . Short duration bursts of the carrier frequency are transmitted in a variety of telemetry transmission formats. exist

The RF carrier frequency is set to 175kHz on the production line, and the IMD's RF telemetry antenna is typically a coil of wire wrapped around a ferrite core inside a sealed enclosure. The RF telemetry antenna of the external programmer is incorporated into a programming head and permanent magnets that can be placed on the patient's skin over the IMD to create a magnetic field within the IMD's sealed housing.

In uplink telemetry transmissions from implanted medical devices, it is desirable to limit the current leakage from the implanted battery as much as possible in order to prolong the lifetime of the device. However, as device operation and monitoring capabilities increase, it is required to be able to increase the capacity of transmitted data in real time or within the shortest possible transmission time with high reliability and immunity to spurious noise. As a result of these considerations, a number of RF telemetry transmission data encoding schemes have been proposed or are currently in use in an attempt to increase the data transmission rate.

Currently, a wide variety of IMDs are commercially available or proposed for clinical implantation that can be programmed in multiple modes of operation and can be interrogated using RF telemetry transmissions. Such medical devices include implantable cardiac pacemakers, cardioverters/defibrillators, pacemaker/cardioverters/defibrillators, drug delivery systems, cardiac stimulators, cardiac and other physiological monitors, Electrical stimulators (including nerve and muscle stimulators), deep brain stimulators, and cochlear implants, as well as cardiac assist devices or pumps. As technology develops, IMDs become more complex in terms of possible programmable modes of operation, menus of operating parameters available, and the addition of monitoring capabilities for a variety of physiological conditions and electrical signals. These complexities place greater demands on the programming and interrogation systems and the healthcare providers who use them.

In our Statutory Inventions Registration H1347 we disclose improvements to such programmers that add audio voice statements during operation to assist healthcare providers using them. For example, we propose the addition of voiced representations that track the programmer's interaction with the implanted medical device during programming, and patient follow-through conversations that can be heard by the healthcare provider using the programmer. Such voiced statements will supplement or replace the visual display or minimal audible tone (e.g., buzzer sound) of such information that is Displayed or issued when the system analyzer is activated.

Other methods relying on RF telemetry transmissions have also been developed to provide real-time warnings to patients when IMDs are misoperating or when detection will require treatment. It has been suggested to incorporate audible beeping alarms into IMDs to warn patients of depleted batteries, such as disclosed in US Patents 4,345,603 and 4,488,555, which are incorporated herein by reference. Likewise, it has been proposed in U.S. Patents 4,140,131 and 5,076,272 and in the '603 patent incorporated above to apply low-energy stimulation to electrodes on or near the IMD to "sting" the patient when the battery is depleted, the The patent is incorporated herein by reference. The use of an audible beeping alarm incorporated into an implantable cardioverter/defibrillator to warn a patient of an impending cardioversion shock is disclosed in US Patent 4,210,149, incorporated herein by reference.

Furthermore, the use of a beeping audible warning of an implantable pacemaker battery depletion in an external monitor, apparently directly coupled to the implantable pacemaker, has been suggested in US Patent No. 4,102,346. Acoustic voice recordings have been incorporated into external medical devices to provide warnings or instructions as disclosed in U.S. Patents 5,285,792, 4,832,033, and 5,573,506, which are hereby incorporated by reference

As noted above, the history of IMD development has been marked by increasing dexterity and complexity in design and operation. In some cases, however, it is desirable to provide a simplified IMD with limited features and controllable modes of operation and parameters for use in developing countries or that can be controlled by the patient.

As an example of the foregoing, simplified and low-cost programmable, single-chamber cardiac pacemaker pulse generators, particularly intended to meet requirements in emerging countries, are disclosed in commonly assigned U.S. Patents 5,391,188 and 5,292,342, which are in This quote is for reference. To avoid the need for an expensive external programmer, the low-cost pacemaker disclosed in the patent was designed using a simplified programming scheme and a simple EKG display coupled to skin-contact electrodes for simple display of artificial pacing pulses and patient ECG. In this low cost implantable cardiac pacemaker, programming is achieved by repeatedly timed application of a magnetic field to the IMD as described above to gradually increase or decrease pacing rate, pacing pulse width amplitude, etc. The magnetic field can be applied or removed manually, and the polarity of the magnetic field can be reversed. Magnetic field sensors and associated programming circuitry within the IMD make incremental changes in response to the applied magnetic field and polarity. The healthcare provider must closely observe the EKG display and calculate the change in pacing rate from the observed change in pacing interval and scale the change in pulse amplitude. This requires fine hand-eye coordination and quick mental calculations to determine when the desired rate or magnitude change has been achieved.

可植入神经刺激器和

药物渗入系统。允许病人通过发射“增加”和“降低”命令来调节刺激和药物治疗。已植入医疗装置对编程命令作出响应，但是不把该响应通过通信返回给病人，而病人还在关心所要求的调节是否已经完成。In the latter case, a neurostimulation device and drug delivery system may be implanted in the patient and the patient provided with an external programmer for providing limited modulation of stimulation therapy and drug release to allow them to adjust the delivered therapy. This device includes

Implantable neurostimulators and

Leakage of the drug into the system. Allows the patient to adjust stimulation and medication by issuing "increase" and "decrease" commands. The implanted medical device responds to programming commands, but does not communicate the response back to the patient, who is concerned whether the required adjustments have been made.

All of the aforementioned RF telemetry systems require complex circuitry and bulky antennas as described above, and are expensive to implement into an IMD. The RF telemetry transceiver within the IMD consumes power from the device's battery when in use. In addition, telemetry systems all require the use of expensive and complex external programmers that establish telemetry protocols, encode and transmit downlink telemetry transmissions, and receive, decode, and display and/or record uplink telemetry transmissions. Record and/or only visually display uplink telemetry data from the IMD and device operation (such as delivery of pacing pulses by an implantable cardiac pacemaker), which requires careful care by the healthcare provider operating the programmer Visual observation. It would be desirable to provide a simple method of transmitting IMD information upon interrogation commands that does not require the patient or healthcare provider to use dedicated RF telemetry equipment and RF telemetry capabilities in the IMD. This is especially the case where the patient is programming limited modes of operation and parameter values using a limited function programmer. As will be apparent from the following description, the present invention satisfies many of these needs.

References made and incorporated by reference to earlier publications or patents anywhere in this specification are intended to simply indicate the state of the art and/or that certain conventional structures, circuits, etc. may be employed in the practice of the invention. The disclosure of these references is not intended to limit the scope of the invention to the specific embodiments shown herein.

Contents of the invention

The present invention is directed to improving the above-mentioned prior art system for communicating with an IMD of the above-mentioned type to interrogate the IMD's mode of operation, parameter values, operating conditions, and stored data.

In one aspect of the invention, communication is effected using voiced statements or sounds stored in and transmitted by the IMD as modulated radio frequency signals in uplink transmissions upon receipt of interrogation commands from the IMD And was triggered.

In another aspect of the present invention, a simplified system is provided for receiving radio frequency signals for uplink communication to a patient or healthcare provider, including tuned to the IMD's broadcast signal frequency and capable of being read by the patient and/or healthcare provider. Traditional radio heard by the patient's healthcare provider. An IMD includes a radio frequency transmitter and antenna that employs amplitude modulation or frequency modulation in the commercially available amplitude modulation or frequency modulation (AM or FM) frequency bands to effect the playback or transmission of voiced utterances or musical tones. Frequencies on the low end of AM or FM are generally not occupied by broadcast stations and are preferred so that simple, readily available and inexpensive AM or FM radios can be used to receive and reproduce broadcasts or transmissions. However, other broadcast frequency bands such as CB, UHF/VHF television and weather radio bands and corresponding receivers can also be used.

During an IMD interrogation session, audible voiced statements or other audible sounds reproduced by the radio reveal a wide variety of IMD information. These transmitted and audibly reproduced IMD information preferably include stored physiological data, IMD programmed operating modes and parameter values, and voiced statements of IMD or component condition or status (e.g., IMD battery condition), as well as information accompanying real-time IMD operation. Voice statement or musical tone. The transmitted and audibly reproduced IMD information also includes voiced statements of patient identification, IMD identification, date of implantation, date of last interrogation, etc., and the IMD can be programmed with these data.

The present invention can be implemented in a simple, low cost interrogation and programming scheme to provide dedicated uplink transmission of IMD information including stored data and operational status or confirmation of device operation and programming changes. These voiced statements or musical tones are produced during such IMD programming by a healthcare provider following a simplified programming protocol using timed manual application of a magnetic field to the IMD. However, the present invention can also be implemented in complex RF telemetry programming and interrogation methods and protocols, selectively replacing or augmenting during interrogation of IMD data, operating modes and parameters and during reprogramming of operating modes and parameters. Uplink RF telemetry transmission and display of IMD information.

It is advantageous to record an audio drive signal that produces a voiced statement or other audible sound (eg, musical tones) in a solid state non-volatile analog memory location within the IMD having a defined memory address. The voiced statements are preferably recorded at the time of manufacture or distribution in the language appropriate to the patient or the country or person in which the patient resides. In one embodiment where sufficient non-volatile memory is provided, voiced statements can be recorded in multiple languages, the appropriate language being selected by programming select commands. In more complex IMDs with RF telemetry capability, a specific language can be selected via a downlink RF telemetry command. In the low-cost IMD disclosed here, a series of repeating magnetic fields can be provided, which can be used to select languages when decoding. The ability to record voiced statements in the local prevailing language or to select pre-recorded voiced statements allows for more flexible, less error-prone and safer audible feedback and control. If the patient moves to a country or place where the prevailing language differs from the prevailing language in the country or place the patient left, the doctor or other healthcare provider can select the language of the spoken presentation.

A plurality of audio drive signals of voiced statements or musical tones conveying or indicative of IMD information of the types listed above are stored in analog memory. In a hardware embodiment, the logic circuit generates the unique memory address of the audio drive signal by accessing the appropriate audio drive signal in either query or programming sequence. In a microprocessor based embodiment, an operating algorithm is employed to sequentially generate addresses for the appropriate audio drive signals. During the interrogation and programming sequence, an appropriate audio drive signal is retrieved or applied to the radio frequency transmitter to produce an AM or FM transmission. At other times, a monitored condition, status or emergency or completed operation of the implantable medical device, or a condition or state of the patient causes a message trigger to be generated depending on the condition. The unique memory address of the message or warning to be broadcast is determined by the message trigger.

To save energy, AM or FM transmissions are low power, short duration, and have a range of a few feet or meters in order to save energy, avoid awkward parts in the IMD, and avoid interference. The antenna may comprise a discrete radio frequency antenna within the IMD housing, if the IMD employs elongated leads, or an elongated wire of such a lead body. RF telemetry antennas of more complex RF telemetry systems may also be adapted or modified for use in the practice of the present invention. Low-power radio-frequency signals can be picked up or transmitted by a low-cost body-worn radio receiver located within a few feet or meters of the patient.

Description of drawings

These and other advantages and features of the invention will likewise be better understood by reference to the following detailed description of preferred embodiments of the invention, when considered in conjunction with the accompanying drawings, throughout which like reference numerals designate like parts, where:

Figure 1 shows a simplified schematic diagram of the communication between a programmable IMD in a patient and a healthcare provider, interrogation and programming thereof is effected using audible voice statements or musical tone feedback, which are determined by the recipient Emissions from external radios for AM or FM transmissions from the IMD;

2 is a block diagram of an example pacemaker implantable pulse generator (IPG) for use in the system of FIG. 1, operating in accordance with FIGS. 3A-3C and 4 when a magnet is applied to the patient's skin over the IPG;

3A-3C are timing diagrams depicting the sequential application of a magnet to the IPG of FIG. 2 and the response of the IPG to the applied magnetic field, including device operation and voice statements generated during interrogation and programming sequences;

Figure 4 is a memory address location diagram depicting voiced statements made by the IMD during the interrogation and programming sequences shown in Figures 3A-3C;

FIG. 5 is an expanded block diagram of the audio feedback circuit block of FIG. 2, illustrating how an audio drive signal is generated, and the modulated audio drive signal is played or transmitted in the AM/FM transmitter in the interrogation and programming sequence shown in FIGS. 3A-3C. The voice statement shown in ;

6 is a block diagram of the analog store/playback integrated circuit (IC) of FIG. 5;

Figure 7 is a sequence diagram depicting the generation of two word messages in the block diagram of Figure 5;

Figure 8 is a block diagram of a microcomputer-based IMD operating system intended for use with a controller and monitor or therapy delivery system of the type shown in Figure 10 capable of being interrogated or programmed by sequential application of a magnetic field and capable of emitting IMD information received by the radio device;

9 is a block diagram of a microcomputer-based IMD operating system intended for use with a controller and monitor or a therapy delivery system of the type shown in FIG. transmit IMD information received by the radio;

Figure 10 is a block diagram of a digital controller/timer circuit usable with the operating system of Figure 8 or Figure 9 and with one of the monitor and therapy delivery devices shown;

FIG. 11 is a diagram depicting memory address locations of audio drive signals for voiced statements or musical tones in the implantable drug delivery device of FIG. 10 having the operating system of FIG. 8 or 9 issued during the interrogation and programming sequence; and

12 is a diagram depicting memory address locations of audio drive signals for voiced statements or musical tones in the implantable electrical stimulation device of FIG. 10 having the operating system of FIG. 8 or 9 issued during the interrogation and programming sequence.

Detailed ways

The preferred embodiment of the present invention discloses the use of conventional low cost AM or FM or radio signals transmitted or broadcast by the radio frequency of the receiving IMD during a communication session involving interrogation or programming of device operating modes or parameters or providing patient alerts or messages. Audio voice statements or musical tones emitted by other frequency band radio devices. Musical tones or voiced statements can be heard by a physician or other healthcare provider to augment or replace a visual display, or to confirm a programming change, or listened to by the patient to confirm that the patient has initiated programming. The present invention may be implemented in all of the above referenced IMDs that provide monitoring and/or dispense therapy to a patient. The present invention can be implemented in a simplified low-cost programming scheme to provide dedicated uplink transmission of IMD information. The audio voice statements preferably also assist the healthcare provider in following programming or interrogation protocols during initial implantation or thereafter.

The present invention can also be implemented into sophisticated RF telemetry programming and interrogation methods and protocols to selectively replace or augment uplink RF telemetry transmissions of device operating modes, states, operations and parameter values. In this case, the modulation of the transmitted audio drive signal may be at the prevailing RF carrier frequency of these RF telemetry transmissions, for example at 175 kHz. Alternatively, a radio may be incorporated into the programmer using the AM or FM band telemetry system described herein.

The following description with reference to FIGS. 1-7 is directed to various preferred embodiments of the present invention implemented in the housing of a low cost, single chamber, implantable cardiac pacemaker IPG that is Programmed using permanent magnets. This implementation can be incorporated into a more complex, dual chamber, programmable pacemaker or pacemaker/cardiverter/defibrillator IPG (as described with reference to Figures 8-10). Other applications of audio communication accompanying the programming or interrogation of the IMD identified in FIG. 10 are then described. Figures 11 and 12 illustrate specific uses of an implantable substance delivery system and an implantable electrical stimulator, respectively. Those skilled in the art will readily adapt the teachings for the IMDs listed here and for other IMDs to be designed in the future.

1 is a simplified schematic illustration of audio feedback of data from an IMD 100 implanted in a patient 102, which occurs during interrogation or programming to confirm changes in device operating modes or parameter values or to generate alarms at other times. For ease of illustration, IMD 100 is preferably a cardiac pacemaker including pacemaker IPG 110 and pacing leads 120 extending from IPG connector 112 to one or more pacing/sensing electrodes, These electrodes are placed in or on the patient's atria or ventricles in a conventional manner. Thus, pacemaker IPG 110 is shown as either a programmable, single-chamber atrial IPG operating in an atrial pacing mode, or a programmable, single-chamber ventricular IPG operating in a ventricular pacing mode. In addition, in the preferred embodiment described below, pacemaker IPG 110 has the working structure of low-cost, single-chamber pacemaker IPG combined with the following audio frequency feedback features of the present invention, said low-cost, single-chamber pacemaker IPG is Disclosed in the commonly assigned '188 and '342 patents cited above.

In the embodiment of FIGS. 2-7, telemetry or communication with the IMD is established by a physician or other healthcare provider by applying permanent magnet 130 to the patient's skin over IPG 110 or removing it according to the protocol described below. dialogue. The magnetic field constitutes a communication link signal detected by the IPG 110 to establish a communication session. During the communication session, interrogation of IMD information and programming of pacemaker IPG 110 operating modes and parameter values are carried out.

MC 13176单个芯片AM/FM发射器的形式。The magnetic field polarity is sensed by a magnetic field sensor 70 within the pacemaker IPG 110 housing. Interrogation and programming protocols are recognized by decoding and logic circuits coupled to the magnetic field sensor in the manner described below. According to the low cost pacemaker preferred embodiment of the present invention, each protocol causes stored voice statements to be transmitted as radio frequency signals by radio frequency transmitter 31 (eg AM or FM band transmitter). Transmitter 31 operates in conjunction with an antenna, which may comprise a discrete radio frequency antenna within the housing of the IMD, or in the case of pacemakers, ICDs, and nerve or muscle stimulation devices, may comprise an elongated conductor lead of a lead body, such as lead 120 . Transmitter 31 can be tuned to the appropriate frequency band

Form of the MC 13176 single chip AM/FM transmitter.

In the sequence established by the protocol, when the magnet 130 is applied to the patient's skin or when the magnet is removed, the physician or other healthcare provider tunes the AM or FM radio 142 to the appropriate AM or FM radio frequency transmission frequency and listens to the radio frequency transmitted by the radio speaker. 144 An uttered vocal statement or musical tone. Although not specifically described, it is understood that a healthcare provider may also use an EKG display or recorder to observe artificial pacing pulses in the manner described in the above-referenced commonly assigned '188 and '342 patents. AM or FM transmission 146 uses low power to save power and minimize IMD size and avoid interference problems, so radio 142 may need to be close to or worn on the patient's body.

This same process can be used by a patient to provide therapy, or to monitor a condition, or to alter parameters of therapy, such as initiating or changing the intensity of electrical nerve stimulation or dispensing a dose of pain relief pills to manage pain.

FIG. 2 is a block diagram depicting a small, lightweight, limited-function, implantable pacemaker IPG circuit 10 in accordance with one embodiment of the present invention and is of FIG. 1 of the commonly assigned '188 and '342 patents cited above. Revise. Modifications include the addition of battery monitor circuit 17, audio feedback circuit 25, RF transmitter 31, RF antenna 117 (or via capacitor 129 connected to lead terminal 12), filter and amplifier circuit 33, optional activity sensor 116 and rate Response circuit 35, and connection lines to some other circuit blocks. It should be understood that the even numbered circuit blocks in FIG. 2 may take the form of, and be equivalent to, those circuits disclosed in detail in the above-referenced commonly assigned '188 and '342 patents. Specific embodiments of these circuits have been identified in the commonly assigned '188 and '342 patents cited above, and references to prior patents are made for illustrative purposes only. Reference to these circuits is not intended to limit the scope of the invention to these specific embodiments of the circuits. The inventors believe that the selection of particular circuits is not critical to the invention so long as they function as a whole to accomplish the operation of the invention.

Pacemaker IPG circuitry 10 is housed in a sealed housing of IPG 110 implanted in patient 102, coupled at IPG connector 112 to atrial or ventricular cardiac pacing lead 120 (as shown in FIG. 1 ). The pacemaker IPG circuit 10 provides single chamber pacing and can be used in conjunction with ventricular pacing leads or atrial pacing leads to provide ventricular pacing or atrial pacing in conventional VVI or AAI and associated programmable pacing modes.

It should be understood that throughout this disclosure, the various internal electronic components, including the pacemaker IPG circuit 10, are coupled to a battery including a battery 13 (e.g., a commercially available manganese dioxide ( _MnO2 ) camera battery, etc.). power supply11. For the sake of clarity, the connections of all circuit blocks to the power supply 11 are not shown in FIG. 2 . However, the power supply 11 is shown coupled to the battery monitor 17, providing a warning trigger signal (in this case) representative of the battery voltage to the electrical replacement indicator (ERI) input of the audio feedback circuit 25 during device interrogation to trigger the voice battery state (as described below with reference to FIGS. 3A-3C ). According to another aspect of the present invention, an alert trigger signal may also be used to periodically trigger the generation of radio frequency alerts played by and received by the external radio 142 . An audible audible sound emitted by speaker 144 of radio 142 can be heard by patient 102 to alert the patient of depleted battery voltage and appropriate action to be taken. Other messages can also be conveyed from the IMD to the patient in this manner.

The battery monitor 17 periodically compares the output voltage of the battery 13 with a reference voltage therein, and optionally provides an ERI warning trigger signal to the ERI input when the battery voltage drops below the reference voltage. This battery monitor 17 follows the teachings of commonly assigned US Patent 4,313,079, which is hereby incorporated by reference. Although not depicted in this embodiment, it is understood that the ERI signal can also be applied to the increase-decrease control circuit 90 to adjust the pacing rate to a percentage of the programmed pacing rate, and to the activity rate response circuit 90. 35 (if present) to prohibit its operation. For example, increase/decrease circuit 90, for example, adjusts the programmed 70 ppm pacing rate down to an ERI rate of 58 ppm based on the ERI signal during normal VVI or AAI pacing.

Pacemaker IPG circuit 10 includes output and pump circuit 14 which delivers pacing (pacing) pulses to terminal 12 and atrial pacing appended thereto in response to a pacing trigger signal generated by pulse width one-shot circuit 16. leads or ventricular pacing leads. In general, output and pump circuit 14 corresponds to the pacing pulse output circuit disclosed in commonly assigned US Patent 4,476,868 or other conventional pacing pulse output circuits, which is incorporated herein by reference. The output and pump circuit 14 further includes a programmable amplitude control circuit disclosed in detail in the above-referenced '342 patent, which allows programming of the pacing pulse amplitude by means of an amplitude programming signal applied to the pump (P) input. In a preferred embodiment, the pacing pulse amplitudes are programmable between high, medium, and low amplitudes.

The activity of the electrical heart inside the patient is monitored by means of a conventional filter circuit 18 coupled to terminal 12 and a sense amplifier 20 for filtering the intrinsic cardiac electrical signal from the patient's heart and zoom in. Filter circuit 18 performs a basic bandpass filtering operation on the raw atrial or ventricular cardiac electrical signal and provides a conditioned signal to the input of a conventional sense amplifier 20 . Sense amplifier 20 is configured to detect P-waves or R-waves and provide a SENSE output signal on line 21 . The sense output of sense amplifier 20 is directed on line 21 to the clock (CL) input of D flip-flop 46 .

According to this embodiment of the invention, a slow (e.g., 10 Hz) master timing clock signal generated by 10 Hz oscillator circuit 22 controls the timing operation of pacemaker IPG circuit 10, an output from rate limit decode circuit 26 is enabled via line 40 The oscillator circuit 22 . Referring to Fig. 10 of the commonly assigned '188 and '342 patents cited above, a 10 Hz oscillator circuit 22 is shown and described in detail. Whenever the 10Hz oscillator circuit 22 is activated, it emits 4 10Hz pulses over a 400 millisecond time period; it then remains dormant until it is activated again. A 10 Hz timing clock signal generated by oscillator circuit 22 is applied via line 24 to the negative CL (clock) input of rate limit decode circuit 26, blanking decode circuit 28, and refractory period (refractory) decode circuit 30, and ANDed ( AND) an input of gate 32. Rate Limit Decode Circuit 26, Blanking Decode Circuit 28, and Refractory Period Decode Circuit 30 define the upper rate limit period, blanking period, and refractory period, respectively, by counting the cycles of the 10 Hz clock supplied to their negative CL input on line 24 cycle.

When a pacing pulse is delivered or when a sense signal is generated, for a blanking interval (e.g., 100 milliseconds corresponding to a 10 Hz clock period) from which the conventional blanking circuit 28 provides the blanking signal to the sense signal. Measuring amplifier 20. It will be appreciated that, depending on the desired length of the blanking interval and the actual oscillation rate of the oscillator circuit 22, blanking periods including a greater number of clock cycle counts may be defined. The blanking signal effectively disconnects the sense amplifier input from terminal 12 during the blanking time period to allow artificial pacing pulses to disappear (which would otherwise saturate sense amplifier 20) and avoid double sensing the internal P-wave or R-wave.

Refractory period decoding circuit 30 defines a refractory period period that tracks each sensed or paced cardiac event. The refractory period decoding circuit 30 measures the refractory period period by counting the cycles of the 10 Hz clock from line 24, just as the blanking decoding circuit measures the blanking time interval. In this preferred present embodiment of the invention, a refractory period period on the order of about 300 milliseconds is believed to be suitable. In this case, the refractory period decoding circuit 30 may define the refractory period period to last for 3 10 Hz clock periods.

During the refractory period, refractory decoding circuit 30 provides a logic low refractory output signal on line 44 and applies it to the D input of D flip-flop 46 . The output of sense amplifier 20 on line 21 is applied to the CL input of flip-flop 46 . As long as the refractory period decoding circuit 30 provides a logic low refractory period output signal to the D input, the Q output of the D flip-flop 46 remains at a logic low level and cannot transition to a logic high level. However, after the refractory period period has expired, the refractory period signal applied to the D input on line 44 returns to a logic high level. At this point, the assertion of a sense signal on line 21 (as described below, caused by the sensed event) triggers the Q output of D flip-flop 46 on line 48 to a logic high, non-refractory period sense signal .

A logic high or logic low on line 48 is applied to one input of AND gate 32; and a 10 Hz clock signal is applied to the other input of AND gate 32 (as described above). If the refractory period has not expired, the output of AND gate 32 and the signal level on line 50 remain logic low. If the refractory period has expired, line 48 will go to a logic high level when a "sense" event is detected. A "SENSE" signal on line 21 after the expiration of the 300 millisecond refractory period causes the Q output of D flip-flop 46 to transition to a logic high level. The next positive excursion of the 10 Hz clock signal will then cause the output of AND gate 32 to transition to a logic high level. The output of AND gate 32 is directed to the reset (R) input of flip-flop 46 on line 50 . Thus, the Q output of D flip-flop 46 is caused to toggle when the signal on line 50 goes to a logic high level on the next clock signal following the sense signal (which is generated after the refractory period expires). to a logic low level.

The non-refractory period sense signal on line 48 is also applied to one input of OR gate 52 and the pulse width trigger signal on line 55 is applied to the other input of OR gate 52 . The output of OR gate 52 is directed on line 56 to the set (S) input of rate limiting, blanking and refractory period decoding circuits 26, 28 and 30. A logic high pulse on line 56 corresponding to the non-refractory period sense signal or the pulse width trigger signal sets and restarts the upper rate limit time interval, the blanking time interval and the refractory period time interval. In addition, when the rate limiting decoding circuit is set, its logic high enable signal applied on line 40 enables the 10Hz oscillator circuit 22 which again sends four 10Hz clock pulses.

Rate limit decode circuit 26 defines an upper rate limit for stimulation pulses delivered by pacemaker IPG circuit 10 . In the present disclosed embodiment of the invention, it is believed that an upper rate limit of one pacing pulse every 400 milliseconds, or a maximum pacing rate of 150 PPM, is suitable. If so, the rate limit decoding circuit 26 defines an upper rate limit time interval which lasts for 4 consecutive cycles of the 10 Hz clock (applied to its CL input). When a logic high signal on line 56 is applied to the S input of rate limit decode logic 26 after each "sense" and "pace" event as described above, the output O of rate limit decode circuit 26 tends to logic The low level is about 400 milliseconds period. This logic low signal is applied to the D input of D flip-flop 54 on line 62, and upon a logic high level or transition at the CL input of D flip-flop 54, it prevents the output Q of the D flip-flop from going from logic low to level shifted to a logic high level. The O output signal on line 62 from rate limit circuit 26 returns to a logic high level after the rate limit time interval of 400 milliseconds has elapsed.

Rate one-shot and TMT circuit 58 (hereinafter simply referred to as rate/TMT circuit 58) determines the base pacing rate at which pacing pulses are delivered to the Terminal 12. The pace-off interval between output pulses generated at output O of rate/TMT circuit 58 is programmable, ranging from 460 to 1200 milliseconds, for example, between 130PPM and 50PPM in 10PPM increments. amount to establish a programmable pacing rate. The rate/TMT circuit 58 includes a retriggerable monostable multivibrator that produces an output signal at its output (O) that it switches to when the programmed escape interval time has elapsed. Applied to the CL input of D flip-flop 54 via line 60 . If the 400 millisecond upper rate cycle time has elapsed, the Q output of the D flip-flop 54 is switched to a logic high level based on the output signal on line 60, and the pulse width trigger signal is provided to the pacing pulse one-shot 16 via line 55. Trigger (T) input. During the 400 millisecond upper rate interval, the output signal from rate/TMT circuit 58 on line 60 fails to switch the Q output of D flip-flop 54 to a logic high level and generate a pulse width trigger signal.

At this point, it should be noted that the logic high pulse width trigger signal on line 55 is also directed to the S input of rate limiting, blanking and refractory period decoding circuits 26, 28 and 30 via OR gate 52 and line 56. A logic high pulse width trigger signal on line 56 restarts the upper rate limit time interval, blanking time interval, and refractory period time interval after the 400 millisecond rate limit time interval has expired and the pace escape interval has expired .

When an output pulse is generated on line 60, the programmed pacing escape interval is automatically restarted within rate/TMT circuit 58. The programmed pacing escape interval is also restarted within rate/TMT circuit 58 upon a "sense" event. Applying a rising edge transition of the reset signal from the output of AND gate 82 appearing on line 84 to the R input of rate/TMT circuit 58 restarts the pacing escape interval. The non-refractory period sense signal on line 48 from the Q output of D flip-flop 46 is coupled to one input of AND gate 82, and the normally logic high output of NOR gate 76 is coupled to the other of AND gate 82. an input. Following the expiration of the refractory period time interval indicative of a non-refractory period sense event, the Q output of D flip-flop 46 goes to a logic high level in response to the sense event on line 21 . The rising edge transition is passed through line 48, AND gate 82 and line 84 to the R input of rate/TMT circuit 58 and restarts the pacing escape interval. As long as rising edge transitions occur at the R input of rate/TMT circuit 58 more frequently than the programmed pace escape interval, the output signal on line 60 will stay at a logic low level and will disable the D flip-flop 54 A pulse width trigger signal is generated at the output Q of the

The pulse width trigger signal output by flip-flop 54 is directed on line 55 to the T input of pulse width one-shot 16 which responds by producing a pacing trigger pulse on line 64 having a duration determined by the output and the pulse width of the pacing pulse generated by the pump circuit 14. The pacing pulse width is programmable in the range from 0.1 to 1.0 milliseconds, for example, in the manner described in more detail in the commonly assigned '188 and '342 patents cited above. The pacing trigger pulse output from pulse width one-shot 16 is applied via line 64 to the T input of output and pump circuit 14 which in response applies a programmed amplitude pacing pulse via coupling capacitor 66 to terminal 12 and additionally at the pacing leads on it. The pacing trigger pulse from pulse width one-shot 16 is also applied on line 64 to the R input of D flip-flop 54 to terminate by terminating the latched or stored logic high level at the Q output of D flip-flop 54. Pulse width trigger signal.

In this manner, pacing pulses are generated on demand and applied to the pacing leads depicted in FIG. 1 . In this embodiment, programming of the pacing rate and pacing pulse amplitude and width is accomplished in the manner described and illustrated in detail in the above-referenced commonly assigned '188 and '342 patents. To eliminate commonly used, expensive, bulky, and power-consuming RF telemetry circuits and components, the programming circuits and protocols disclosed herein use solid-state semiconductor devices that are sensitive to applied external magnetic fields. A solid-state magnetic field sensor (MAGFET) 70 suitable for use in IMD telemetry is disclosed in commonly assigned US Patent 5,438,990 to Wahlstrand et al., which is hereby incorporated by reference in its entirety. When no magnetic field is applied, the two output signals N and S on lines 72 and 74 are at a logic zero or low level. As described in the '990 patent, the MAGFET circuit 70 is capable of discriminating between external magnetic fields of two different polarity orientations (eg, between a north-south oriented magnetic field and a south-north oriented magnetic field). Accordingly, MAGFET circuit 70 generates two logic high output signals, N (North) on line 72 and S (South) on line 74 . For example, the N signal is asserted upon detection by the MAGFET circuit 70 that the applied magnetic field is N-S oriented. Likewise, the S signal is established upon detection of the S-N orientation of the applied magnetic field.

Logic circuit 78 receives a logic high N or S signal on line 72 or 74 from MAGFET circuit 70 . Logic circuit 78 detects magnetic field application and magnetic field removal in N-S or S-N magnetic field orientations, respectively. As described below with reference to FIG. 3B , logic circuit 78 sends control signals to up/down control circuit 90 via a plurality of control lines (collectively indicated at 92 in FIG. 2 ). Logic circuitry 78 includes digital logic circuitry for detecting and counting magnet removal and replacement cycles, as described in the above-referenced commonly assigned '188 and '342 patents, and establishing various control signals therefrom to implement Programming of pacing rate, pacing pulse width, and pacing pulse amplitude.

For example, upon detection of a magnet removal/replacement cycle, logic circuit 78 asserts a control signal to up/down control circuit 90 to enter pacing rate programming mode. In the rate programming mode, another control signal is derived from the N or S magnet polarity signal on line 72 or 74, which commands the pacing rate to increase or decrease in steps, respectively.

Increment/decrement control circuit 90 produces a plurality of output signals which lead to the program (P) input of rate/TMT circuit 58, pulse width one-shot 16 and output/pump circuit 14 on lines 94, 96 and 98, respectively. The signals on lines 94, 96 and 98 are analog reference currents which are described in detail in the commonly assigned '188 and '342 patents cited above. The reference currents on lines 94 and 96 determine the duration of the output pulses from rate/TMT circuit 58 and pulse width one-shot 16, respectively, and thus the programmed pacing rate and pulse width. The reference current on line 98 determines the output pulse amplitude from output/pump circuit 14 by developing a reference voltage across resistor 15 . This reference voltage is used in conjunction with a comparator and charging circuit in the output/pump circuit 14 to charge the output capacitor to a programmed voltage magnitude (as is known in the art).

For example, in the case of a pacing rate parameter, up/down control circuit 90 provides a reference current on line 94 to the P input of rate/TMT circuit 58 . Stepping down the reference current level on line 94 causes the pace-break interval established by rate/TMT circuit 58 to increase. Likewise, incrementally increasing the reference current level on line 94 causes the pacing interval established by rate one shot 58 to be incrementally decreased. The pulse width one shot 16 is similarly controlled by the reference current on line 96 . The pacing pulse amplitude of the pacing pulses produced by output/pump circuit 14 is directly controlled by the voltage developed across resistor 15 which is in turn controlled by the voltage developed on line 98 by up-down control circuit 90 .

The interrogation and programming protocol of this embodiment of the invention is based on the initial detection of external magnetic field application and initial entry into TMT mode as shown in FIG. 1 . After the TMT and interrogation modes are complete, the external magnet 130 is removed and then reapplied according to the protocols disclosed in the above-referenced commonly assigned '188 and '342 patents (for programming operating modes and parameter values, etc.). The number of programmable modes and parameter values for pacemaker IPG circuit 10 is relatively more limited than is typical with more complex programmable cardiac pacemakers. For example, in this embodiment, the basic pacing rate, pacing pulse width, and pacing pulse amplitude parameters are programmable within selected ranges. Single chamber asynchronous and triggered pacing modes and other parameters such as sense amplifier sensitivity, refractory period period and activity threshold and gain factor described in the above-referenced commonly assigned '096 patent can be programmed. In the case of a programmable dual chamber pacemaker, the pacing upper rate limit and A-V delay interval can also be programmed. Some arrangement must be made to select which parameter or mode to program so that different parameter values and modes of operation can be programmed separately. Control of the parameters or modes to be programmed has been achieved in some existing pacemakers by downlink RF telemetry, which sends the identification code along with the new value or new mode to the receiver of the implanted pacemaker. identify.

In TMT mode, rate/TMT circuit 58 provides a preset number (e.g., 3) and outputs pulses at the TMT pacing rate on line 60 to D flip-flop 54, which provides 3 corresponding pulses at its Q output. wide trigger pulse. The non-refractory period sense event signal generated by D flip-flop 46 in response to the sense signal is blocked from resetting rate/TMT circuit 58 . AND gate 82 is blocked by a logic low signal output from NOR gate 76 on line 80 due to a logic high (N or S) level on one input of this gate. As such, the amplifier circuit 20 continues to operate, but effectively disables its output signal as long as the MAGFET 70 senses a magnetic field.

The asynchronous TMT sequence helps the healthcare provider determine whether the currently programmed pacing pulse width and pulse amplitude settings are sufficient to achieve "capture" of the patient's heart, ie sufficient to cause it to contract. In the presently disclosed embodiments of the invention, the TMT sequence may be one as disclosed in commonly assigned US Patent 4,273,132 to Hartlaub, which is hereby incorporated by reference in its entirety. Pacing pulses generated during a TMT sequence may have a higher than normal pacing rate to distinguish the TMT sequence from asynchronous pacing pulses preceding and following it. The amplitude or pulse width of at least one TMT pacing pulse is reduced to a percentage of the programmed amplitude or pulse width. In the conventional programmed system described in the '132 patent cited above, during this time, the healthcare provider observes the patient's heart activity on the EKG monitor and sees whether all three pacing pulses result in systole. If one (or more) TMT pacing pulses do not capture the heart, the healthcare provider can increase the programmed pulse width or pulse amplitude and perform the TMT sequence again to verify that the pacing pulse energy is sufficient to capture the heart with proper safety margin.

After the rate/TMT circuit 58 performs a TMT, the IPG circuit 10 begins asynchronous pacing at the nominal rate (e.g., 70PPM), or at the programmed rate, or at the ERI rate, if used, as long as the MAGFET 70 continues to Detect N or S magnetic fields. According to the mode of operation described in the commonly assigned '188 and '342 patents cited above, a protocol is followed to program the pacing rate, pulse width and/or amplitude, which specifies the Appropriate movement to manually remove or reapply N or S magnetic fields.

Referring to FIG. 2, the following operations are implemented in the audio feedback circuit 25, which will be described in more detail below. Briefly, when an N or S signal is generated on line 72 or 74, the output signal of NOR gate 76 is applied to audio feedback circuit 25 on line 80 as a MAGNET signal. The magnet signal causes power to be applied from the power supply 11 to the components of the audio feedback circuit 25 described below, which are normally not powered in order to conserve battery 13 energy. The audio feedback circuit 25 includes logic circuitry for specifying memory addresses of analog musical tones or voice statements that are retrieved from analog memory and applied as audio drive (A-D) signals to AM/FM transmitter 31 for transmission. To conserve battery power, the AM/FM transmitter 31 is only powered by the SW signal and is coupled to the Audio Drive Signal (ADS) output when necessary during interrogation or programming sessions or passing messages to the patient.

The pacing trigger signal on line 64 and the non-refractory period sense output signal of trigger 46 on line 48 are directed to corresponding pacing and sensing (pacing and SENSE) inputs of audio feedback circuit 25 . Signals representing pacing pulse amplitude, pacing rate and pacing pulse width established in up/down control circuit 90 are directed to the AMP, RATE and PW inputs of audio feedback circuit 25 on lines 91, 93 and 95, respectively. When the battery voltage drops below the reference voltage in battery monitor 17, the upper ERI signal on line 23 is applied to the ERI input of audio feedback circuit 25, as described above.

The audio feedback circuit 25 also includes a pacing/sensing (pacing/SENSE) event counter that is activated to count pacing trigger pulses and sense event signals generated after the magnet signal is received. The event counter initially counts the pacing trigger pulses of the TMT sequence as long as the magnet signal is present, and then counts the asynchronous pacing trigger pulses during the asynchronous interrogation mode. In the illustrated embodiment, the pace/sense counter counts a fixed number of pace trigger and sense signals when the magnet signal is terminated. The count (CNT) is applied to logic circuit 78 on line 73 as the timing for reapplying the magnetic field. The counts of the pacing/sensing event counter are used to address the voiced statements transmitted in time synchronized to each pacing and sensing event.

According to this embodiment of the invention, the audio feedback circuit 25 and AM/FM transmitter 31 are energized during TMT, the voiced statement "pace" is retrieved from analog memory and transmitted on each pacing pulse of TMT, and The voiced statement "TMT Pacing" is transmitted upon delivery of the final reduced energy pacing pulse of the sequence. The correct voiced statement is appended to the pacing pulse delivered in the TMT sequence using a pace/sense (pace/SENSE) event counter count. A series of voiced statements are then retrieved and transmitted in an interrogation sequence that begins after the TMT and continues until completion, regardless of whether the magnetic field continues to be applied. In the embodiment of FIGS. 2-4, the voiced statement includes manufacturer, device model and serial number identifiers, battery status, and parameter values including pacing rate, pacing pulse width, and pacing pulse amplitude. However, if pacing modes and other operating parameters such as sense amplifier sensitivity, refractory period period, activity threshold, etc. are made programmable, the voiced representations may include other representations of these programmed modes and parameter values.

Fixed rate pacing pulses are delivered after completion of this TMT sequence as long as the magnetic field is not disturbed. According to this embodiment, the delivery of each pacing pulse is accompanied by a "pace" statement that is retrieved and fired until the magnetic field is removed. In another variation, only a fixed number of "pace" statements may be retrieved and transmitted, and the magnetic field may be retained to maintain fixed rate pacing for extended diagnostic or therapeutic purposes. When the pace/sense event counter reaches a fixed count (eg, 10), RF transmissions for the "pace" statement are stopped. The pacing/sensing event counter may be turned off at this point or may continue to count pacing trigger signals. In addition, when the magnetic field is subsequently removed, a fixed number of asynchronous pacing pulses accompanied by a retrieved and fired "pace" statement may be delivered to aid in the timing of reapplying the magnetic field to enter programming mode.

Pacing mode returns to programmed mode, which is typically AAI or VVI mode, but can be triggered mode (AAT or VVT) if no magnetic field is reapplied and sensed during delivery of a fixed number of asynchronous mode pacing pulses. It is possible to temporarily place the IPG in inhibited mode to determine if an intrinsic cardiac event is sensed, but such a test may not be safe for the patient. Preferably, after the magnetic field is removed and the asynchronous mode is terminated, the retrieved and transmitted "pace" or "sense event" is counted by the pace/sense event counter and then signaled with a fixed number (e.g., 10) of pace trigger or sense events. test" statement. In the absence of a non-refractory period sense event, at the end of the pacing escape interval, the pacing trigger pulse continues with the "paced" statement retrieved and transmitted until this count is reached. As shown in Figure 2, non-refractory period sensing events are counted and RF transmissions of the "sensing" statement are triggered, but it is possible to alternate between refractory period and non-refractory period sensing events Ground counts and emits the "sense" statement.

A preferred embodiment, in the sequence of events involved in interrogating and/or programming pacemaker IPG 10, may be better understood with reference to the timelines of FIGS. 3A, 3B and 3C. In FIGS. 3A , 3B and 3C, pacing pulses are represented by solid vertical lines denoted P ₀ , P _{1 ,} etc., and sensed events are represented by dashed vertical lines denoted S ₁ , S _{2 ,} etc. In FIGS. Figure 3A depicts interrogation of pacemaker IPG identifier, programmed pacing rate and pulse amplitude, battery condition, and retrieved and transmitted pacing and sensing events. In FIG. 3A, it is assumed that pacemaker IPG 10 is normally on until time T1, at which time magnet 130 (as shown in FIG. 1) is applied. For example, upon detection of the programming magnet at T1, pacemaker IPG circuit 10 begins delivering 3 pacing pulses _P1 , _P2 , _P3 at an asynchronous rate of 100PPM. Pacing pulses _P1 and _P2 are at programmed pulse amplitudes, however, pacing pulse _P3 is at a reduced pulse amplitude to determine if the patient's heart can be captured by a reduced energy pacing pulse. The healthcare provider can observe the 3 artificial pacing pulses on the EKG monitor, and if the pacing pulse energy exceeds the patient's pacing threshold, the combined image of the PQRST caused by the pacing pulse is also shown. A retrieved "START TMT" statement is transmitted by the AM/FM transmitter 31 shortly after the magnet signal is generated. The "PACE", "PACE" and "TMT PACE" statements are retrieved and transmitted synchronously with the next 3 pacing triggers of the TMT sequence.

In FIG. 3A, after completion of the TMT sequence at time T2, pacemaker IPG circuit 10 remains in an asynchronous (AOO or VOO) mode in which pacing pulses _P4 through _Pn are delivered at a programmed or nominal asynchronous rate (e.g., 70PPM). . Alternatively, if the ERI signal is present and applied to the increase/decrease control circuit 90 (as described above), the asynchronous rate may be 58 ppm of the decrease rate. It will be appreciated that the time interval of asynchronous pacing between time T2 and time T3 in FIG. 3 may last for an indeterminate period of time as long as programming magnet 130 remains in place. However, the "pace" statement of retrieval and transmission can only continue until a predetermined number "n" of retrievals and transmissions have been made and then stop to conserve battery power. The magnet is removed at time T3, and the pacemaker IPG (eg, AAI or VVI mode) returns to the programmed pacing mode, (at the programmed pacing rate and pacing pulse amplitude and width). Alternatively, another number, eg, 10, of asynchronous pacing pulses may be delivered after T3 and before reverting to the programmed pacing mode. This feature allows the magnet to be removed at any time after T1, and allows TMT, uplink telemetry, and asynchronous pacing to continue until completion after such removal of the magnet as described above.

Returning to time T2, in the depicted interrogation sequence, audio feedback circuit 25 begins to retrieve the AD signal and applies it to AM/FM transmitter 31, causing AM/FM transmitter 31 to transmit analog voice statements. In this example, the retrieved and transmitted voiced statements include a number of phrases selected from the list of memory addresses depicted in FIG. 4 . Retrieves and transmits the pacemaker manufacturer, model, and unique serial number, followed by a retrieved and transmitted phrase stating the programmed pacing rate, programmed pulse width, high, medium, or low programmed pacing pulse amplitude, and battery status. If the logic level at the ERI input to the audio feedback circuit 25 indicates normal, start of life, battery energy, then the battery status statement "Battery OK" is retrieved and transmitted. If the battery monitor 17 generates an ERI signal in response to detection of depletion, end of life, battery energy, then the battery status statement "Battery Empty" is retrieved and transmitted. It should be noted that the healthcare provider may leave the magnet 130 in place (as shown in FIG. 1 ), or remove it at any point during the interrogation sequence described above. Even if the magnet is removed before all statements of the query sequence are retrieved and transmitted, the retrieval and transmission of voiced statements can continue to complete. For example, the "paced" statement is suppressed at pacing pulses P ₄ through P ₇ while retrieving and transmitting these identifier and status statements of the query sequence. The "pace" statement is retrieved and transmitted after completion of the interrogation sequence as long as application of the magnet continues or until a predetermined count "n" is reached.

At time T3 in FIG. 3A , the magnet 130 is removed from the patient 102 shown in FIG. 1 ; and the magnet signal is no longer applied at the magnet input of the audio feedback circuit 25 . As shown in FIG. 3A , audio feedback circuit 25 starts an internal event counter of 10 pacing or sensing events, e.g., to continue programming the pacing rate, pulse width or breadth. The sense amplifier 20 is no longer effectively disabled and the non-refractory period sense signal is clocked in the rate/TMT circuit 58 through the AND gate 82 and resets the pacing escape interval. The termination of each escape interval (due to a non-refractory period sense event or the expiration of the escape interval time) is applied to the sense and pace inputs of the audio feedback circuit 25 which count them. The audio feedback circuit 25 continues to retrieve the AD signal from memory and provide it to the AM/FM transmitter 31, after delivering each pacing pulse (such as at _Pn+1 and _PN+10 ) and delivering each sense signal ( At S _n+2 and S _n+3 ) the statement "pace" or "sense" is modulated and transmitted (as shown in Figure 3A). During this sequence, the healthcare provider can use the radio to receive, demodulate, and emit the "pace" and "sense" voiced statements (or musical tones representing it) and correlate them with a visual display of the same event. When a predetermined count of "pace" and "sense" events are accumulated in the event counter of the audio feedback circuit 25, the retrieval and transmission of the voiced statement ceases.

The illustration of FIG. 3A assumes that the magnetic field is no longer applied during the 10 pacing and sensing events after time T3 (counted by the event counter and provided to logic block 78 on line 73 ). FIG. 3B depicts a programming protocol sequence initiated by a single reapplied permanent magnet providing a magnet signal on line 80 during the above sequence after T3 but before counting 10 pace or sense events. During this time period, the healthcare provider or physician can hear and count several retrieved and transmitted "pace" and "sense" statements sent by the radio, and decide to reapply the magnet 130. time to the patient's skin. Upon completion of the 10 event window, a single reapplication of the magnetic field during the 10 event window is decoded in logic circuit 78 to begin the pacing rate programming sequence in which the base pacing rate is programmed.

FIG. 3C depicts a programming protocol sequence initiated by two reapplications of a permanent magnet providing signal N or S on line 72 or 74 during the program after T3 above but before counting 10 events. The two reapplications of the magnetic field within the 10 event count window are decoded in logic circuit 78 to begin the pacing pulse amplitude programming sequence in which the pacing pulse amplitude is programmed. Likewise, three reapplications of the magnetic field within a 10 event count window are decoded in logic circuit 78 to begin the pacing pulse width programming sequence in which the pacing pulse width is programmed.

Programming any of these three programmable parameters is accomplished by first initiating the TMT and interrogation sequence (as described above with reference to Figure 3A). Then, after time T3, the appropriate number (1, 2 or 3) of magnet removal/replacement cycles must be performed within a 10 event count window to cause the logic circuit 78 to switch to programming for programming the required parameters model. This method and ability to hear the retrieval and transmission of the "pace" and "sense" statements by the radio makes it easy to reliably apply or The permanent magnet 130 is removed from the patient's skin to select the desired parameters for reprogramming.

During the magnet removal/reapply cycle depicted in FIGS. 3B and 3C , it can be observed that the reapply magnet 130 is held in place to provide the selected N-S or S-N magnetic field to the MAGFET 70 during the ensuing programming mode. Accordingly, the continuously generated N or S signal is applied through NOR gate 76 to one input of AND gate 82 to effectively disable sense amplifier 20 and initiate pacing in an asynchronous mode. Pacing pulses are then delivered at the currently programmed pacing rate, pacing pulse width, and pulse amplitude. Logic circuit 78 decodes the number of applications for magnet 130 removal and replacement and provides a corresponding programming mode control signal to up/down control circuit 90 via line 92 .

Once in the decoded programming mode, the increment/decrement control circuit 90 adjusts the value of the corresponding parameter by an increment on each asynchronous pacing cycle to either increment or reduce. For example, start the rate programming mode by completing the TMT and interrogation modes, then remove and replace the magnet once (as shown in Figure 3B). As long as the N signal remains present on line 72, indicating detection of an N-S oriented magnetic field, increase/decrease control circuit 90 increases the pacing rate by one increment (eg, 5PPM or 10PPM) per pacing cycle. Conversely, as long as the S signal remains present on line 74, representing the S-N oriented magnetic field, increase/decrease control circuit 90 decreases the pacing rate by the same increment each pacing cycle. Thus, the pacing rate is programmed to the desired value by maintaining an S-N or N-S oriented magnetic field on the MAGFET circuit 70 for sufficient pacing cycles to achieve the desired level. When the desired rate is reached, simply remove the magnet to terminate rate programming.

In the commonly-assigned '188 and '342 patents cited above, verification of pacing rate changes was validated by observing delivery of redundant pacing pulses indicating parameters indicated by Their number is programmed. In rate programming, two such pacing pulses were generated at the end of each pacing cycle (also shown in Figure 3B) 5 milliseconds apart. In pulse amplitude programming, three such pacing pulses (also shown in FIG. 3C ) are generated at 5 msec intervals at the end of each pacing cycle. Assume, in order to indicate programming of the pacing pulse width, that 4 such pacing pulses are generated at the end of each pacing cycle. The number of redundant trigger pulses shows which parameter is being programmed, but does not reveal the programmed parameter value. Errors may occur in the counting of pacing cycles, and incremental changes in these parameter values are not easily observed or measured from an EKG trace being printed or displayed on a video screen. It is necessary to know what the starting parameter is, and to mentally calculate the variation from this value by counting escape intervals until the final parameter value is reached. If the initial pacing pulse width or amplitude or pacing rate is not known and cannot be measured, it may be necessary to follow a programmed sequence to increase or decrease the programmed parameter value to its upper or lower limit. The upper or lower limit is reached by counting out the maximum number of escape intervals corresponding to the total number of possible incremental values. A new parameter value is then programmed by incrementally subtracting the parameter value from the maximum value or increasing the parameter value from the minimum parameter value by a sufficient number of increments or decrements to achieve the desired programmed value.

According to yet another feature of the invention, at the end of each escape interval, the audio feedback circuit 25 and the AM/FM transmitter 31 are used to retrieve and transmit a statement of the programmed parameter value. As such, redundant and energy-wasting pacing pulses need not be used, and there is no need to calculate the correct number of pacing cycles required to make a correct change in parameter value, or to count out pacing cycles. This results in a simpler, more reliable, and error-prone programming function, with the advantages of reduced cost and improved patient safety.

Thus, the redundant pacing pulses used in the above-referenced commonly assigned '188 and '342 patents are depicted in Figures 3B and 3C, but it is understood that they are not required in the practice of the present invention. When programming mode is entered through one, two, or more magnet removal/replacement cycles, a voiced statement of the parameter being programmed (e.g., "programming rate") is retrieved from analog memory, transmitted by an external radio, and retrieved and reproduced. ” or “Program Amplitude”).

Additionally, at each incremental change, a pacing rate, pulse width, or pulse amplitude change is retrieved and transmitted, as depicted in Figures 3B and 3C. In this embodiment, especially at high pacing rates, it may be necessary to make incremental programming changes and transmit change values only at the end of every second or third or fourth escape interval, to provide enough time for the radio to transmit and hear the entire phrase. Or the phrase can be shortened to simply state the pacing rate number of 5 or 10 and the pulse width stated in milliseconds. In addition, a sharp or flat musical tone may be transmitted and played by the radio before or after each incremental increase or decrease in the programmed parameter value, respectively, to indicate that the parameter value is being changed. As described below, in some IMDs, one or more sharp or flat musical tones may be transmitted after each parameter value increase or decrease without having to retrieve and transmit the actual value in the transmitted voice statement.

Figure 4 shows an example list of pacing rates, pulse widths, and pulse amplitudes that are retrieved and transmitted in programming mode and encode them into memory addresses for an analog memory array that will be described below with reference to Figure 6 describe. For example, voiced statements for pulse widths ranging from 0.1 milliseconds to 1.0 milliseconds in 0.1 millisecond increments and voiced statements for pacing rates ranging between 50 PPM and 100 PPM in 5 PPM increments are stored in memory. For example, the voiced statements "amplitude low", "amplitude medium" and "amplitude high" of pacing pulse amplitudes of three programmable amplitudes are also stored in memory.

单片话音记录/回放器件之一，这是由位于美国加利福尼亚州Los Alton Hills的InformationStorage Devices公司销售的，尤其是图6中所示的ISD33060型。在美国专利4,890,259中(所述专利在此引作参考)和其它有关的ISD专利中揭示这种模拟存储/回放IC。FIG. 5 is an expanded block diagram of the audio feedback circuit 25 of FIG. Additionally, a voice input block 206 is shown in dashed lines illustrating analog retrieval and transmission of voiced statements and/or storage of musical tones in the analog memory of the analog storage/playback IC 200 . The recording is generally performed during the manufacture of the pacemaker IPG or other IMDs, and of course this recording can also be performed after the completion of the manufacture of the pacemaker IPG. Analog storage/playback IC 200 preferably ISD33000 series Chip

One of the single-chip voice recording/playback devices is sold by Information Storage Devices, Los Alton Hills, California, USA, specifically the type ISD33060 shown in FIG. 6 . Such an analog store/playback IC is disclosed in US Patent 4,890,259, which is hereby incorporated by reference, and other related ISD patents.

In FIG. 5, the timing control circuit 202 and the IPG circuit are interconnected to receive a pacing trigger pulse on line 64, line 48 whenever an N (increase) or S (decrease) signal appears on lines 72 and 74, respectively. The sense event signal on , and the magnet signal on line 80 . Timing control circuit 202 builds upon the protocol shown in FIGS. 3A-3C and described above, and generates the commands shown in FIG. 5, which are applied to address generation circuit 204 or AM/FM transmitter 31 and logic 78. These commands are generated in particular during the TMT mode shown in Figure 3A, the asynchronous interrogation mode and then the normal operating mode. To save energy, the SW signal generated by the timing control circuit 202 increases the power of the AM/FM transmitter 31 only during the transmission time window.

The address generation circuit 204 also receives the ERI signal from the battery monitor 17 on line 23 and also receives the pulse amplitude (AMP), pacing rate (RATE) from the increase/decrease control circuit 90 on lines 91, 93 and 95, respectively. and Pulse Width (PW) to program operating parameter values. During the asynchronous interrogation mode of FIG. 3A, the AMP, RATE and PW programming parameters and the ERI signal are converted to the memory addresses listed in FIG. 4 as programmed values and battery conditions. These commands prompt the address generation circuit 204 to select and apply to the address (ADDRESS) input line of the analog store/playback IC 200 the voice statement memory addresses described above and listed in FIG. 4 .

It is possible to combine speech statements taken in cascade from two memory addresses to form a retrieval and emission phrase as shown in FIG. 7 . For example, the voice of "Pace XX PPM" can be selected cascadingly from the "Pace" statement and the "XX PPM" rate statement at the two addresses depicted in Figure 4 using the pacing signal and programmed pacing rate values phrase (where "XX" is the current programmed value).

During the programming mode illustrated in Figures 3B and 3C, the increased or decreased amplitude (AMP), rate (RATE) and pulse width (PW) programming parameter values are likewise converted to the memory addresses listed in Figure 4, and applied to the address input of the analog store/playback IC 200.

Address generation circuit 204 also provides a "not on chip" (NEC) command and a "play" command to analog store/playback IC 200 in order to initiate or trigger playback on the address provided to the "address" bus. The addressed recorded voiced statement or other audible sound is provided to AM/FM transmitter 31 of FIG. 2 through playback filter and amplifier stage 208 as an A-D signal. When the retrieved A-D signal statement is complete, the logic level on the "Not Ended Message" (NEOM) line transitions to the reminder timing control circuit 202, which queues the next command to the address generation block 204. The above sequence of device identification, operating condition and mode or state, and retrieval and emission statements of programmed parameter values are generated sequentially in interrogation mode by "handoff" cooperation between timing control 202 and analog store/playback IC 200. Likewise, each device operation, i.e., a pace trigger pulse or sense event signal causes timing control 202 to instruct address generation circuit 204 to provide an address to analog store/playback for the retrieved and transmitted "pace" or "sense" statement Address input for IC 200. To place analog store/playback IC 200 in a "zero power" mode when not in use, address generation circuit 204 also provides a "power down" (PWR_DWN) logic level to analog store/playback IC 200.

Voice input block 206 is used to record voiced statements and/or musical tones over line 211 at predetermined addresses in analog storage/playback IC 200. The voice input block 206 provides the address and provides a record command signal on the play/record line and a chip fail (NCE) signal on the NCE line. The NCE input receives an enable logic level to start recording of the addressed voiced statement (or musical tone) on the address bus.

Figure 5 also includes an additional circuit for retrieving logged messages or warnings as A-D signals when appropriate to transmit warnings to the radio indicating device misoperation or urgently administering medical treatment where appropriate. Various IMD monitoring devices may be provided for periodically or continuously monitoring the condition, status or emergency operation of an implantable medical device, or the condition or status of a patient, and providing message triggers based thereon. Voice statements telling the patient to contact his/her physician or healthcare provider may also be stored and transmitted.

The ERI signal is a message trigger signal that will trigger the address generation and retrieval of the "battery dead" A-D signal transmitted by the AM/FM transmitter 31 described above. A timer is used in the address generation block, which responds to the ERI signal and can generate the address of this warning to the patient periodically (eg, once an hour), so that it is not generated continuously. The ERI warning can be automatically set OFF when an interrogation or programming sequence is performed according to FIGS. 3A-3C to allow these functions to be performed. Additionally, in more complex multi-programming embodiments than illustrated in FIG. 2, the healthcare provider may use the programmer to transmit the appropriate programming commands, to program or not program this function.

模拟存储/回放IC 200是CMOS器件，它工作在3伏下并提供存储在非易失性模拟存储阵列210中的模拟话音记录的60秒回放。如下所述，通过耦合到地址缓冲器214的译码器212对模拟话音记录寻址，并提供给模拟输出放大器226。模拟存储阵列是多级存储，专用于ISD的EEPROM，在上面引用的ISD′259专利中进行详细的描述。FIG. 6 is a simplified block diagram of an analog storage/playback IC 200 that includes elements for recording voiced statements or sounds in a non-volatile analog storage array 210 . The analog storage/playback IC 200 also retrieves the recorded statements and voices and passes them on the analog outputs A-D+ and AD- to the filter and amplifier stage 208 which processes them and provides the AD signal to the AM/ FM transmitter 31. ISD 33060Chip

Analog storage/playback IC 200 is a CMOS device that operates at 3 volts and provides 60 seconds playback of analog voice recordings stored in non-volatile analog storage array 210 . The analog voice recording is addressed by decoder 212 coupled to address buffer 214 and provided to analog output amplifier 226, as described below. The analog memory array is a multi-level memory, EEPROM specific to ISD, described in detail in the ISD '259 patent cited above.

The CMOS device includes power conditioning circuitry 230, which is intended to be coupled to external components to form a regulated power supply coupled to power supply 11 for providing power to the other circuitry depicted. Device control circuitry 232 is also coupled to the other circuits depicted and controls device operation according to a predetermined application. In accordance with the present invention, the PWR_DWN signal from address generation block 204 is applied to the PD input of the device control circuit to enter a zero power mode, minimizing battery drain at all times except during voice recording or playback. It can be concluded that audio or voiced statements stored in the non-volatile analog storage array 210 can be retained for 100 years without consuming any power. During playback or recording of voiced statements, a "play" or "record" logic level is applied to the P/NR input. The NCE input receives an enable logic level to begin recording a voiced statement, which is the voiced statement addressed on the address bus, in memory at the specified address for playback of the voiced statement. The NEOM logic level signal is output from device control circuit 232 and applied to timing control 202 when a voiced statement or phrase is complete to allow addressing of the next voiced statement or phrase (as described above).

An on-chip oscillator is provided by internal clock 234, which may also be driven by an external clock XCLK (not used in the practice of the present invention). Internal clock 234 provides a clock signal to internal timing circuit 236 which provides a sampling frequency to sampling clock 238 and 5-pole active anti-aliasing filter 222 and 5-pole active smoothing filter 218 .

The audio sound or voice recording portion of the CMOS device includes a speech or audio input amplifier 220 for amplifying the audio input signal at ANA IN and coupling the amplified signal to an anti-aliasing filter 222. The filtered input signal is sampled by the sampling clock 238 so that the sampled analog value is directly stored in the memory unit by the analog transceiver 216 for later access by the decoder 212 when addressing. The manner in which addresses are stored and allocated is as described in the ISD '259 patent cited above. A preamplifier 240 and AGC circuit 242 are also provided on the IC, but they are not used in the practice of the present invention.

According to one feature of the invention, the voiced statements are recorded in a specific human language after the manufacture of the pacemaker IPG circuit 10 (or other IMD circuit) is complete, but before the circuit 10 is packaged in the IPG housing. Alternatively, recordings of voice or spoken statements are provided to the manufacturer (ISD in this example) and recorded in the analog storage array 210 before the analog storage/playback IC 200 is shipped. In another approach, a pacemaker IPG or other IMD with a feedthrough can be provided for direct coupling to the ANAIN terminal of amplifier 220 to record voiced statements (as described in the commonly assigned '096 patent cited above). way of describing). In this variant, it is possible for the vendor or the doctor who implants the medical device to store voiced statements in the local language of a given country. According to yet another aspect of the present invention, musical tones may also be recorded at certain memory locations via the audio input amplifier 220 for use with the spoken utterances.

According to another feature of the invention, voiced statements can be recorded in more than one language, and the healthcare provider or doctor can select the language to be used. In more sophisticated IMDs with RF telemetry capabilities, specific languages may be selected via downlink RF telemetry commands. In the low cost pacemaker IPG 10 described above, a further repeating sequence of successively removing and replacing magnets 130 for a specified period of time can be detected by appropriate circuitry in logic circuit 78 and applied to address generation circuit 204 to select the language used.

Regardless of how the voiced statements are recorded in the analog memory array 210, when they are addressed by the decoder 212, the retrieved non-transmitted analog speech samples are always sequentially selected from the storage locations in the analog memory array 210. obtained. Analog speech samples are retrieved sequentially through the analog transceiver 216 at the sample clock frequency and applied to a 5-pole active smoothing filter 218 to reassemble the words of the phrase in natural rhythm and phonetic form. The recombined speech representations pass through multiplexer 224 and are applied to input terminals of output amplifier 226 where they are amplified and output at output terminals A-D+ and A-D-. The auxiliary input to multiplexer 224 is not used in the present invention.

Champion^TM单腔起搏器IPG系统与上述较佳实施例共享类似的结构和工作系统，但是，以某种不同的方式通过连续地除去和再施加磁铁进行编程和指示编程工作模式和参数。系统包括

9710型编程器，该编程器仅检测起搏时间间隔并在显示器上显示，使用授予Bennett的共同转让的美国专利4,226,245中所描述的方法来促进ECG解译，所述专利在此引作参考。即使在显示间隔时，也难于在观察和翻译起搏时间间隔显示的同时对起搏速率进行编程，所述观察和翻译是为了对起搏时间间隔进行计数和使编程命令的产生同步于所计的时间间隔。该方法是长时期并有错误的。可以把本发明实施到Champion^TM系统中，在询问序列期间发射话音陈述，以及发射被无线电装置接收的“起搏”和“感测”陈述，以帮助理解TMT操作和时间再编程。It will be appreciated that the preferred embodiment of the invention can be modified to provide different programming and interrogation sequences.

The ^ChampionTM single chamber pacemaker IPG system shares a similar structure and operating system with the preferred embodiment described above, however, programming and indicating programmed operating modes and parameters are performed in a somewhat different manner by sequentially removing and reapplying magnets. system includes

The Model 9710 programmer, which only detects pacing intervals and displays them on the display, facilitates ECG interpretation using the method described in commonly assigned US Patent 4,226,245 to Bennett, which is hereby incorporated by reference. Even when the intervals are displayed, it is difficult to program the pacing rate while viewing and interpreting the pacing interval display in order to count the pacing intervals and to synchronize the generation of programming commands to the counted intervals. time interval. This approach is long term and buggy. The present invention can be implemented into the Champion ^™ system by transmitting voiced statements during the interrogation sequence, as well as transmitting "pace" and "sense" statements received by the radio to aid in understanding TMT operation and time reprogramming.

In the Champion ^(TM) IPG, a measurable percent decrease in the programmed pacing rate in response to an ERI signal allows the healthcare provider to observe the current rate and translate battery depletion from the observed pacing rate. For example, a programmed pacing rate of 75PPM may be reduced to 58PPM when the battery voltage drops below the ERI threshold voltage. A reed switch is included in addition to the MAGFET, which is closed by the applied magnetic field, starting an interrogation sequence that ends with a TMT after magnet removal rather than starting with a TMT sequence. The applied magnet closes the reed switch and switches the pacing mode to asynchronous mode, restoring the programmed pacing rate in the initial sequence of 3-4 asynchronous pacing pulses. If the battery voltage is below the ERI threshold, the asynchronous pacing rate changes to the ERI rate, or remains at the programmed pacing rate for the second sequence of asynchronous pacing pulses. The healthcare provider observes the artificial pacing on the ECG monitor and compares the observed escape intervals to determine if there are significant differences and conclude that the battery voltage is depleted and the IPG needs to be replaced. Then, for example, the magnet is removed, the pacing mode is returned to the inhibit mode at a preset escape interval corresponding to 75PPM, and a fixed number of pacing escape intervals are counted in a third sequence. At the end of this count begins a TMT sequence of 4 asynchronous pacing pulses at an elevated pacing rate and a programmed window sequence that includes a TMT sequence and 7 more pacing pulses, again, the healthcare provider observes the ECG display for Determine if the reduced energy pacing pulses of the TMT sequence capture the heart.

In this embodiment of the invention, at the programmed pacing rate, during the initial sequence of fixed rate pacing pulses, the retrieval and transmission of voiced statements (including battery status) during the interrogation mode of FIG. 3A can be initiated and completed . The second sequence may be incremented by the retrieved and transmitted "Pace XX PPM" statement (where "XX" is the currently programmed value) issued by the radio synchronously with each pacing trigger. Likewise, pacing pulses for a TMT sequence can be augmented by retrieving and transmitting the "Pace" and "TMT Pace" statements from the radio, and pacing pulses for a programmed window sequence can be added by retrieving and emit "pacing" and "sensing" statements while increasing.

In the Champion ^™ pacemaker IPG, only the pacing rate and pacing pulse amplitude are programmable. In the programming sequence of the Champion ^™ pacemaker IPG, the pacing rate and pulse width are programmed using the NS and SN magnetic fields, respectively. During the incremental window between 3 successive pacing pulses, the programmed parameter value was increased when the magnetic field was applied and removed twice rapidly in rapid succession. When the magnetic field is applied and removed one at a time, the programmed parameter value decreases. In each case it is necessary to wait until 3 escape intervals have elapsed together with the pacing trigger before the parameter value can be increased or decreased again. Once the required parameter values are obtained, the magnetic field is no longer applied, and after 10 pacing pulses have been delivered from the last application of the magnetic field, the pacing mode returns to the inhibited pacing mode.

In this embodiment, the invention may be implemented with the voice of the "pace" statement to assist in timing the application of the magnetic field sufficiently far from and within the delta window to avoid programming errors. The retrieved and transmitted "pace" statement may add delivery of the last 10 pacing pulses.

The above-described embodiments of the pacemaker IPG are implemented in custom integrated circuits or more complex microcomputer-based operating systems that incorporate analog memory IC 200 and distribute the timing control and address generation functions of FIG. 5 among other system elements. This approach can be used with many other IMDs, such as electrical stimulators of the type disclosed in commonly assigned US Patent 4,520,825 to Thompson et al., which is hereby incorporated by reference.

8 and 9 are block diagrams of such a microcomputer-based IMD operating system intended for use with a controller and monitor or a therapy delivery system of the type depicted in FIG. 10 . The system of FIG. 8 is programmed and interrogated using simple magnet application and removal methods as described above, while the system of FIG. 9 uses RF telemetry programming and interrogation techniques well known in the art. The microcomputer-based system of FIGS. 8 and 9 includes a microprocessor 152 which communicates via a data and command bus 150 with a RAM 154, a ROM 156, an analog store/playback IC 200, a filter and amplifier stage 208, a battery monitor 17 and a graph. 10 digital controller/timer circuit 158 coupled. Digital controller/timer circuit 158 is coupled to specific monitor or therapy delivery systems 160a-160i, as shown in FIG. Other components or circuit blocks used in a particular IMD may also be connected to the data and control bus 150 .

Analog store/playback IC 200 is configured as described above with reference to FIG. 6 . Using the voice input block 206 and associated signals in the manner described above, the audio drive signals for emitting voiced statements or musical tones are stored in the analog memory array 210 of FIG. 6 . If the A-D signals are recorded during manufacture of the IMD and the option to allow the distributor or physician to record is not provided, the sound input block 206 may not be present in the IMD, or may be disabled. If the voice input block 206 is present and enabled, it will be coupled to the data and control bus 150 to allow its use (particularly in the embodiment of FIG. 9 where appropriate commands can be received in downlink telemetry transmissions ).

In these embodiments, it is not necessary to use the timing control circuit 202 or the address generation circuit 204 of FIG. 5 to control the operation of the analog store/playback IC 200. In this microcomputer-based operating system, the timed operation of analog store/playback IC 200 as described above is controlled by interrogation and programming algorithms stored in ROM 156 and initiated by microprocessor 152. Also stored in ROM 156 are memory location addresses for A-D signals stored in analog memory array 210, and are selectively retrieved and applied to address buffer 214 according to interrogation and programming algorithms.

The IMD of FIG. 8 or 9 together with FIG. 10 is powered by the battery 13 in the power supply 11 and the battery voltage is monitored by the battery monitor 17 . Either the battery voltage is encoded in the battery monitor 17 and provided to the data and command bus 150, or the ERI warning trigger is generated in the battery monitor 17 and encoded and provided to the data and command bus 150 in the manner described above 150 to the microprocessor 152. During the interrogation sequence, the battery voltage itself or a simplified voiced statement that the battery voltage is "normal" or "dead" is transmitted by the AM/FM transmitter 31, as described above.

At other times, if the encoded battery data indicates that the battery 13 is depleted to the ERI voltage, the microprocessor 152 initiates a warning routine, causing the AM/FM transmitter 31 to transmit a warning voice statement or musical tone at an audible volume audible to the patient . During the alert procedure, the microprocessor periodically (e.g., once an hour) retrieves the address of the appropriate A-D signal and directs it over the data and control bus 150 to the address buffer 214 of the analog store/playback IC 200. NCE and NEOM commands are also applied on the data and control bus 150 . Filter and amplifier stage 208 amplifies the A-D signal and applies it to AM/FM transmitter 31 for transmission to the radio.

Other warning programs may also be included in the microcomputer-based operating system for providing such audible warnings transmitted by the radio to the patient when a triggering event occurs. Trigger events may include certain operations of the IMD or other changes or states of the IMD. For example, in the case of an implantable drug delivery system, the patient may be alerted that the drug supply is exhausted. In the case of an implantable cardiac monitor or cardioverter/defibrillator, the patient can get arrhythmias detected by the arrhythmia detection algorithm and take appropriate action. The sudden onset of a malignant condition of the patient is detected and a warning trigger signal is generated based on the detection. The patient is alerted to seek medical help or take other precautions by an audible warning RF transmission. In the case of a cardioverter/defibrillator, the patient may be advised to be in a resting position prior to delivering the cardioverter/defibrillator shock.

In each case, the triggering event causes the microprocessor 152 to retrieve and apply commands for operating the analog storage/playback IC 200 and addresses providing appropriate A-D signals from the non-volatile analog storage arrays of the RAM 154 or ROM 156. 210 retrieves the signal. Analog store/playback IC 200 retrieves the addressed A-D signal and applies it through filter and amplifier stage 208 to AM/FM transmitter 31 which transmits AM or FM voiced statements or musical tone alerts to the patient.

An interrogation and programming system responsive to continuous application of the magnetic field of the MAGFET 70 for interrogating IMD information and for programming device operating modes and parameter values is shown in FIG. 8 . MAGFET 70 senses the polarity of the applied magnetic field and generates corresponding N and S signals on lines 72 and 74 respectively (in the manner described above with reference to FIG. 2 ). The N and S signals are applied to logic circuit 78 which develops an appropriately encoded signal which is applied to microprocessor 152 over data and control bus 150 to initiate a programming or interrogation algorithm. Thus, as shown and described in FIG. 1, a communication session is established by applying the magnet 130 to the patient's skin. The magnetic field constitutes a communication link signal which is detected by the MAGFET 70 to establish a communication session.

In FIG. 9, a communication session is established using a programming and interrogation system based on RF telemetry transmissions for interrogating IMD information and for programming device operating modes and parameter values, typically a programming head of a programmer (not shown) ( not shown) includes a permanent magnet that closes reed switch 166 and generates a downlink RF telemetry signal that is received by RF telemetry antenna 168 and applied to RF telemetry transmitter/receiver circuit 164 . RF telemetry transmitter/receiver circuitry 164 decodes and then encodes received downlink RF telemetry signals for transmission on data and control bus 150 and constitutes communication link signals. The uplink RF telemetry transmission of the IMD information received on the data and control bus 150 is generated in the RF telemetry transmitter/receiver circuit 164 and applied to the RF telemetry in the uplink telemetry transmission routine. Antenna 168. Microprocessor 152 initiates the uplink RF telemetry transmission routine and provides data and control signals on data and control bus 150 to RF telemetry transmitter/receiver circuitry 164 .

The system of Figure 9 can be configured in many different ways to share the uplink communication capability of the audible sound produced by the AM/FM transmitter 31 with high speed RF telemetry received by the programmer technical uplink transmission. In a simple application, an RF telemetry transmission system may be used to receive programming and interrogation commands and echo interrogation data and programming confirmation at frequencies in the AM or FM bands, radio built into the programmer or a separate radio take over. It should be noted that the 175kHz telemetry antenna within the IMD can be used to transmit AM or FM frequency signals, and a single antenna can be designed with switching circuitry to operate optimally on both RF frequencies depending on the switching state.

In the system of Figure 8, the patient is provided with a magnet to program limited operating modes and parameter values, and receives audible feedback confirming such programming or asking for certain IMD information. It will be appreciated that the interrogation and programming system of Figure 8 could be included in the working system of Figure 9 to allow the patient to use the magnet for the same purpose. Or the patient may be provided with a limited function programmer for limited interrogation and RF telemetry downlink transmission of programming commands (audible transmissions in response to corresponding IMD messages).

In this regard, high volume audible audible RF transmission capabilities may also be used during programming or interrogation procedures that allow patient self-initiation. For example, if a patient is provided with a limited programmer or magnet for increasing or decreasing drug doses or symptom-relieving electrical stimulation, programming changes can be confirmed by RF transmissions of voiced statements or musical tones that are received and played back by the radio. In each case, the programming change causes the microprocessor to retrieve or apply commands for operating the analog store/playback IC 200 and the addresses of the appropriate A-D signals. Analog store/playback IC 200 retrieves the addressed A-D signal and applies it through filter and amplifier stage 208 to AM/FM transmitter 31 which transmits a voiced statement or musical tone confirming the change to the patient. Some examples are described below with reference to FIGS. 11 and 12 .

Figure 10 is a block diagram of a digital controller/timer circuit 158 that may be used with the operative system of Figure 8 or Figure 9 with therapy delivery devices 160a-160h or physiological monitor 160i. It will be appreciated that many equivalent therapy delivery devices 160a-160h also have monitoring capabilities that accumulate physiological data for later interrogation. It will be appreciated that logic circuit 78 and RF telemetry transmitter/receiver 164 of FIGS. 8 and 9 may be incorporated within digital controller/timer circuit 158 in any particular therapy delivery device and monitoring configuration. In the case of each IMD configuration, a digital controller/timer circuit 158 and an appropriate programmable operating algorithm 162 control all operating functions.

As for the therapy delivery device configuration, the IMD may be configured to operate an implantable cardiac assist device or pump 160a implanted in a patient awaiting heart transplant surgery. In this case, the resulting relative blood pressure and/or body temperature values can be used to adjust pump action to maintain proper cardiac output. Or it can be configured to include one or a combination of anti-tachycardia pacemaker 160b, anti-bradycardia pacemaker 160c, cardioversion device 160d and/or defibrillation device 160e, with the ability to deliver medical Apparatus 100 extends to appropriate leads and electrodes of the patient's heart 10 for sensing an electrocardiogram (EGM) and delivering pacing pulses or cardioversion/defibrillation shocks. The IMD may be configured to include a substance delivery device 160f coupled to a suitable conduit extending to a location on the patient's body to deliver a substance, such as a therapeutic or diagnostic agent or drug, from a substance reservoir. For example, drugs to treat high blood pressure can be delivered to the patient's heart 10 or vascular system.

According to one aspect of the present invention, the memory stores audio drive signals indicative of delivery of the substance to body tissue. An acoustic drive signal associated with mass transfer is applied to the radio frequency transmitter. A radio frequency transmitter broadcasts a modulated radio frequency signal that can be detected or demodulated by a radio receiver, producing human intelligible voiced statements or other audible sounds indicative of substance delivery. According to a further aspect of the invention, the depletion of the substance reservoir is monitored or queried periodically. An audio drive signal indicative of the amount of substance released or remaining in the substance reservoir is stored at a memory location having a specified memory address. The delivery of quantitative substances is monitored. Measures or calculates the quantity of substance delivered or the quantity remaining in the reservoir at each delivery or upon receipt of a substance quantity interrogation command, and retrieves the stored audio drive indicating the quantity of substance delivered or the quantity remaining in the reservoir from a memory location Signal. The radio frequency transmitter broadcasts a modulated radio frequency signal that can be detected and demodulated by a radio receiver, producing a human intelligible voiced statement or other audible residual message indicating the amount of material delivered or remaining in the reservoir.

Transform^TM心肌刺激器160g，它具有，伸展到病人心脏和包围心脏的骨骼肌肉的合适引线，以感测心脏EGM和定时传递肌肉刺激脉冲。还有，可以使用所得到的相对血压和/或体温值来调节肌肉刺激速率，以维持合适的心脏输出。还可以把IMD配置成电刺激器160h，它包括神经和肌肉刺激器、大脑刺激器和耳蜗植入，用于把电刺激治疗施加到病人体内合适位置的电极上。IMD can be configured as

Transform ^™ myocardial stimulator 160g, which has suitable leads extending to the patient's heart and surrounding skeletal muscles to sense cardiac EGM and timed delivery of muscle stimulation pulses. Also, the obtained relative blood pressure and/or body temperature values can be used to adjust the rate of muscle stimulation to maintain proper cardiac output. The IMD can also be configured as an electrical stimulator 160h, which includes nerve and muscle stimulators, brain stimulators, and cochlear implants for applying electrical stimulation therapy to electrodes at appropriate locations within the patient's body.

Reveal^TM可植入环路记录仪具有表面电极和记录42分钟时段的EGM。Chronicle^TM可植入血流动力学记录仪采用在共同转让的美国专利5,535,752号和5,564,434中所揭示的引线和电路，以预定的时间间隔记录EGM和绝对血压值，所述专利在此引作参考。Finally, the IMD can also be configured as an implantable monitoring system that monitors physiological conditions, such as an EGM to monitor a patient's heart and/or a cardiac monitor that monitors blood pressure, temperature, and blood gas or pH. When the patient senses an arrhythmia and activates the recording function by applying a magnet to the implant,

The Reveal ^™ Implantable Loop Recorder has surface electrodes and an EGM that records a 42 minute period. The Chronicle ^™ Implantable Hemodynamic Recorder records EGM and absolute blood pressure values at predetermined time intervals using the leads and circuitry disclosed in commonly assigned U.S. Patent Nos. 5,535,752 and 5,564,434, which are incorporated herein by reference .

In any of these therapy delivery systems or monitoring systems, a variety of IMD information can be conveyed by means of retrieved and transmitted voiced statements or musical tones stored in the analog storage array 210 of the analog storage/playback IC 200. Two specific examples are shown in FIGS. 11 and 12 showing how the present invention can be used to simplify the interrogation and programming of IMDs, which typically provide limited functionality for the patient to program to ease the patient's perceived discomfort. symptom.

可植入神经刺激器和

药物渗入系统，以允许病人调节刺激和药物治疗以缓解病痛症状。根据本发明的下述实施例，当病人使用这种病人激励器或磁铁进行编程以调节刺激和药物治疗时，音乐音调被IMD发射到无线电装置。根据使用病人激励器或磁铁，在传递已增加刺激能量或定量药剂治疗时，可以把一系列的升音阶音乐音调发射到无线电装置。同样地，根据使用病人激励器或磁铁，在传递降低的刺激能量或定量药剂治疗时，可以把一系列的降音阶音乐音调发射无线电装置。此外，伴随升音阶或降音阶音乐音调或谐音还可以检索已编程刺激能量或定时药剂的剂量并将其发射到无线电装置。In these embodiments, the patient is typically provided with a patient actuator or programmer to turn therapy on or off and/or increase or decrease therapy parameters. In particular, the above mentioned referenced

Implantable neurostimulators and

Drugs are infiltrated into the system to allow the patient to adjust stimulation and drug therapy to relieve symptoms of pain. According to an embodiment of the invention described below, musical tones are transmitted by the IMD to the radio when the patient is programmed to adjust stimulation and medication using such a patient actuator or magnet. Depending on the use of patient exciters or magnets, a series of ascending musical tones can be transmitted to the radio while delivering increased stimulation energy or dosing medication. Likewise, depending on the use of patient actuators or magnets, a series of descending musical tones may be transmitted to the radio while delivering reduced stimulation energy or dosing medication. Additionally, programmed stimulation energy or doses of timed medicaments may be retrieved and transmitted to the radio along with sharp or flat musical tones or harmonics.

FIG. 11 is a diagram depicting memory address locations of A-D signals for transmitting voiced statements or musical tones during the interrogation and programming sequence of the implantable drug delivery device 160f of FIG. 10 having the operation of FIG. 8 or FIG. 9 system. The diagram of FIG. 11 depicts memory address locations for retrieving and transmitting voiced statements or musical tones in the current IMD information query sequence at analog memory addresses "00"-"0D" and subsequently at addresses "0E"-"0F ” on the programming sequence used to increase or decrease the rate of drug penetration. In the interrogation and programming sequence, the healthcare provider can start the interrogation, he can use the programmer in the case of using the configuration of the working system of Figure 9, or he can use the magnet in the case of using the configuration of the working system of Figure 8 130.

Assuming the latter case, and assuming that IMD 100 of FIG. 1 is a drug delivery system incorporating drug delivery device 160f, the healthcare provider applies magnet 130 to MAGFET 70, which produces N or S on line 72 or 74 of FIG. Signal. Logic circuit 78 responds by providing an interrupt to microprocessor 152 to begin the query routine. Analog memory address "01" is provided on bus 150 to analog storage/playback IC 200, which emits the voiced statement "Data Start" or musical tones at a discernible audible frequency. Then, the query program sequentially selects one of addresses "02"-"05" as the current infiltration rate, selects "06"-"0A" as the remaining drug amount, and selects "0B"-"0C" for battery condition. In these cases, the A-D signal causes the RF emission of the voiced statement. Then, an "END DATA" statement or another musical tone is transmitted to the analog storage/playback IC 200 on the bus 150 at the same or different frequency as the "DATA START" by providing the address "OD".

During the interrogation sequence, the battery voltage is monitored and an appropriate one of address "0B" or "0C" is provided to analog store/playback IC 200 at a designated point in the sequence. The detection of the magnet 130 causes the microprocessor 152 to suspend the periodic RF transmission of the dead battery warning that would occur at other times when the battery 13 is depleted to the ERI voltage. Likewise, detection of the magnet 130 causes the microprocessor 152 to suspend periodic RF transmissions of the drug exhaustion warning that may occur at other times when the amount of drug is depleted to "less than 2 days' worth" or less. However, it will be appreciated that during normal operation these voiced statements or musical tone alerts are transmitted to the radio at addresses "0A" and "0C".

Magnet 130 can be removed to end the interrogation sequence, or it can be left in place or rotated from end to end to begin a programming sequence to increase or decrease the dosing rate. In each case, the programming sequence was started in the rate increase mode by providing the address "OF", causing the RF transmission of the "rate increase" voiced statement or sharp musical tone. Then, within a few seconds, the healthcare provider can either leave the magnet 130 in place to continue the rate increase mode, or flip it from side to side to switch the programming sequence to the rate decrease mode. In the former case, after a few seconds, commands from the microprocessor 152 step up the rate and store the currently programmed rate in the RAM 154 so that the digital controller/timer circuit 158 is on the dosing cycle. It is used periodically in the program. The microprocessor 152 then applies the analog memory address of the A-D signal of the increased rate voice statement to the analog memory/playback IC 200 on the data and control bus 150, causing retrieval and RF transmission of the voice statement to the radio to confirm the rate The change. At this point, assuming the maximum rate has not been reached, the healthcare provider may choose to increase the rate by leaving the magnet 130 in place for a few seconds and repeating the process through the next rate increment. Alternatively, the healthcare provider may choose to terminate the programming sequence at the new programmed rate by simply removing the magnet 130 before retrieving and firing the next rate change. A similar process follows, by inverting the magnetic field and using memory address "0F" if a reduced rate of dosing is required, to produce a descending musical tone or "rate reduction" voiced statement.

Using the configuration of the programming and interrogation system of FIG. 8, for example, it is also possible to provide the patient 102 with the magnet 130 and to follow instructions to increase or decrease dosing therapy to treat the ailment. In this case, it is assumed that the IMD is programmed with musical tones at the time of manufacture using audible sound input 206 at addresses "00", "0A", "0D" (rather than equivalent voice statements). The patient 102 is advised to apply the magnet 130 and follow the procedure described above until a sharp musical tone is heard. Then, by following the steps above, the rate can be increased or decreased. For safety reasons, the maximum rate at which a patient can be programmed can be limited in the manner described, for example, in commonly assigned US Patent 5,443,486 to Hrdlicka et al., which is hereby incorporated by reference.

电刺激器、

电刺激器以及电刺激器和双通道

电刺激器。12 is a diagram depicting memory address locations of AD signals for transmitting voiced statements or musical tones during interrogation and programming sequences of the implantable electrical stimulator 160h of FIG. working system or its hard-wired equivalent. Such implantable electrical stimulators include, but are not limited to, those that electrically stimulate the spinal cord, peripheral nerves, muscles and muscle groups, the diaphragm, various parts of the brain, body organs, etc., wherein electrical impulses are delivered to all on the electrodes to be stimulated. Commercially available electrical stimulators of this type include

electrical stimulator,

electrical stimulators and Electrical stimulator and dual channel

electrical stimulator.

The table of Figure 12 depicts the memory addresses of the A-D signals for use in an interrogation sequence for the current IMD information at address locations "00"-"1D" and at address locations "00"-"14" and "18"-"1D". ” to transmit voiced statements or musical tones in a programmed sequence of programmable parameter values and modes. The table of FIG. 12 also shows memory address locations "0E" and "1F" for increasing or decreasing stimulation parameters (such as pulse amplitude or Pulse width or pulse rate or electrodes) to emit sharp and flat musical tones in a programmed sequence. In the interrogation and programming sequence, the healthcare provider can use the programmer to start the interrogation in the case of the configuration of the working system of FIG. 130 Start inquiry. A limited function programmer may be provided to the patient for programming one or more programmable parameter values and modes of operation.

The following description assumes the use of a magnet programming and interrogation system and assumes that IMD 100 of FIG. 1 is an electrical stimulator 160h with leads 120 applied to muscles other than the heart. The healthcare provider applies magnet 130 to MAGFET 70, which generates an N or S signal on line 72 or 74 of FIG. Logic circuit 78 responds by providing an interrupt to microprocessor 152 to begin the query routine. Memory address "15" is provided on bus 150 to analog store/playback IC 200, which retrieves the stored voice statement identifying the IMD. The interrogation program then sequentially selects one of the programmed addresses "00"-"06" for the current pulse rate, "07"-"0E" for the current (i.e., previously programmed) pulse width, and "0F" - "14" for current pulse amplitude. The query continues by selecting address "16" or "17" for battery condition, address "18" or "19" for cycling on or off states, and addresses "1A"-"1D" for programming electrode configuration. In these cases, the A-D signal is applied to the AM/FM transmitter 31, causing the RF transmission of the voiced statement. In the illustration of FIG. 1, these retrieved voice statements are transmitted and received, demodulated and transmitted by radio 142 to be heard by the healthcare provider.

During the interrogation sequence, the battery voltage is monitored and the appropriate one of addresses "16" or "17" is provided to the analog store/playback IC 200 at the specified point in the sequence. The detection of the magnet 130 causes the microprocessor 152 to suspend the periodic RF transmission of the dead battery warning that would occur at other times when the battery 13 is depleted to the ERI voltage. However, it will be appreciated that during normal operation, a voiced statement or musical tone alert at address "16" is applied to the AM/FM transmitter 31, causing RF transmission of the voiced statement. In the illustration of FIG. 1, these retrieved voice statements are transmitted and received, demodulated and transmitted by radio 142 to be heard by the healthcare provider.

At this point, the magnet 130 can be withdrawn to end the interrogation sequence, or it can be left in place or rotated from end to end to begin a programming sequence to increase or decrease any programmable parameter (i.e. pulse rate, width, amplitude, period state , and electrodes). The programming sequence begins in rate increase mode by providing address "1E" causing an RF transmission of an "increase value" voice statement or sharp musical tone. Then, within a few seconds, the healthcare provider can either leave the magnet 130 in place to continue the increasing mode, or flip it from side to side to switch the programming sequence to the decreasing mode. Each parameter value and mode of operation can be programmed continuously using a system that continuously causes magnet placement and removal, similar to the system used in the procedure illustrated in Figures 3A-3C.

Assuming the stimulation pulse rate is being programmed to an increasing pulse rate, the pulse rate is incrementally increased by command provided by the microprocessor 152 after magnet application continues for several seconds. The new current programmed pulse rate is stored in RAM 154 for periodic use by digital controller/timer circuit 158 during the stimulus delivery program. Address "1E" for the A-D signal of the voiced statement of increasing rate is then applied to the analog storage/playback IC 200 on the data and control bus 150 by the microprocessor 152, causing the RF transmission of the voiced statement or ascending musical tone , to confirm the rate change. At this point, assuming the maximum pulse rate has not been reached, the healthcare provider may choose to increase the rate by leaving the magnet 130 in place for a few seconds and repeating the process through the next rate increment. Alternatively, the healthcare provider may choose to terminate the programming sequence at the new programmed pulse rate by simply removing the magnet 130 before retrieving and firing the next rate change. If a reduced dosing rate is required, a similar procedure is followed.

With the configuration of the programming and interrogation system of FIG. 8, for example, the patient 102 may also be provided with the magnet 130 and follow instructions to increase or decrease dosing therapy to treat the ailment. In this case, it is assumed that the IMD is programmed at manufacture with musical tones rather than equivalent spoken statements using audible sound input 206 at analog memory addresses "1E" and "1F". The patient 102 is advised to apply the magnet 130 and follow the procedure described above until a sharp musical tone is heard. You can then leave the magnet in place to increase the rate or flip the polarity of the magnetic field to decrease the rate and hear the descending musical tone.

In the context of a microcomputer-based IMD operating system, the embodiments of the present invention shown in FIGS. 8-10 and employing IC 200 of FIG. Logic circuits and registers in timer/timer circuit 158 control the programming and interrogation sequences. The algorithm utilizes timing control circuit 202 and address generation circuit 204 and the interconnections between them and with analog store/playback IC 200 in FIG. 5 . It is understood that in a microcomputer-based operating system, a circuit such as that shown in FIG. 5 can be used. Rather, it will be appreciated that the embodiments may also be implemented in hardware-based systems described above with reference to the sequences of FIGS. 11 and 12 and other sequences that may be designed to use the therapy delivery and monitoring system of FIG. The analog memory addresses are addressed sequentially.

It is therefore to be understood that the foregoing specific embodiments are illustrative of the many ways in which the principles of the invention may be practiced. It is therefore to be understood that other approaches known to those skilled in the art or disclosed herein may be used without departing from the scope of the invention or the appended claims. It is therefore to be understood that, within the scope of the appended claims, the invention may be practiced without departing substantially from the spirit and scope of the invention unless otherwise specifically described.

Claims (31)

1. A system for interrogating stored and real-time generated IMD information of an implantable medical device implanted in a patient and broadcasting the interrogated IMD information to a radio receiver outside the body of the patient , characterized in that the system includes: A device that provides an interrogation signal from a location outside the patient's body to initiate an interrogation procedure for implantable medical device information; and Implantable medical devices further include: a receiving device that receives the interrogation signal and starts the interrogation procedure; a device storing at least one audio drive signal capable of being reproduced as a voiced statement or other audible sound indicating information about the medical device; a radio frequency transmitter for broadcasting a radio frequency signal modulated by an audio drive signal capable of being received and demodulated by a radio receiver located outside the patient's body; and audible feedback means responsive to initiation of the interrogation procedure for retrieving the stored audible drive signal and applying the retrieved audible drive signal to the radio frequency transmitter causing the radio frequency transmitter to play a A modulated radio frequency signal that produces voiced statements or other audible sounds indicating information about the implanted device being queried. 2. The system of claim 1, wherein the medical device information is selected from a group of information, the group of information further includes: medical device manufacturers; medical device identifier; patient identifier; date of implantation; date of last inquiry; stored physiological data; battery condition; real-time device operation; the currently programmed operating mode; the currently programmed operating parameter value; depletion of material reserves; device operation history; and the patient's testing status, The medical device information constitutes a spoken statement or audible sound when reproduced by a radio receiver. 3. The system of claim 1, wherein: The means for storing at least one audio drive signal includes a memory having a plurality of memory locations represented by memory addresses, the plurality of audio drive signals are stored at specified memory addresses; and The audio feedback device further includes: means for selectively generating memory addresses of stored audio drive signals; and means, responsive to the generated memory address, for retrieving an audio drive signal from the addressed memory location and applying the retrieved audio drive signal to the radio frequency transmitter. 4. The system of claim 3, wherein the medical device information stored at the specified memory address with the audio drive signal is selected from a group of information, the group of information further comprising: medical device manufacturers; medical device identifier; patient identifier; date of implantation; date of last inquiry; stored physiological data; battery condition; real-time device operation; the currently programmed operating mode; the currently programmed operating parameter value; depletion of material reserves; device operation history; and the patient's testing status, When reproduced by a radio receiver, the medical device information constitutes a spoken statement or other audible sound. 5. The system of claim 1, wherein the interrogation program is capable of real-time device operation, and the at least one audio drive signal is indicative of real-time device operation of the implantable medical device, the implantable medical device further comprising: means for performing real-time device operations in response to interrogation signals; and The audio feedback device further includes: means for retrieving an audio drive signal associated with the performance of real-time device operation of the implantable medical device; and Applying the retrieved audio drive signal to the radio frequency transmitter causes the radio frequency transmitter to play a modulated radio frequency signal time-correlated to the performance of the real-time device operation, whereby the radio receiver produces a time-correlated signal to the operation of the implantable medical device. Devices that relate verbal statements or audible sounds. 6. The system of claim 5, wherein the real-time device operation and associated audio drive signals are selected from a group of information further comprising: monitor the patient's physiological condition; determine battery condition; and Give treatment to patients. 7. The system of claim 5, wherein the implantable medical device is powered by a battery, and the power of the battery is consumed by the implantable medical device, wherein; the storage means stores at least one audio drive signal, capable of being reproduced as a voiced statement or sound, conveying the power level of the battery; The providing means further includes providing an interrogation command for the power level; the real-time device operation executing the device causes the battery power level to be measured as a real-time device operation; and the retrieval means retrieves the stored audio drive signal indicative of the measured battery power level, The radio frequency transmitter thereby broadcasts a modulated radio frequency signal that can be detected and demodulated by the radio receiver, producing a voiced statement or other audible sound indicative of the battery charge level. 8. The system of claim 5, wherein the implantable medical device is a substance delivery system that releases substance from a dose of substance from a reservoir of defined volume to the patient's body, wherein: The storage means stores an audio actuation signal indicating the amount of substance released or remaining in the reservoir; providing means to provide a quantity of substance interrogation command which causes a measurement of the quantity of substance which has been released or remains in the reservoir; The real-time device operation performing the device causes the amount of substance released or remaining in the reservoir to be measured as a real-time device operation; and the retrieval means retrieves the stored audio drive signal indicating that the amount of substance released or remaining in the reservoir is to be measured, The radio frequency transmitter thereby broadcasts a modulated radio frequency signal which can be received and demodulated by the radio receiver, producing a voiced statement or other audible sound indicating the amount of substance released or remaining in the reservoir. 9. The system of claim 5, wherein the implantable medical device is an electrical stimulator for delivering electrical stimulation to body tissue of a patient, further comprising: Devices for delivering electrical stimulation to body tissue of a patient; and wherein: the storage device stores at least one audio drive signal indicative of delivery of electrical stimulation; and the providing means provides an interrogation command which causes the retrieving means to retrieve the stored audio drive signals indicating the delivery of electrical stimulation each time the electrical stimulation is delivered, The radio frequency transmitter thereby broadcasts a modulated radio frequency signal that can be received and demodulated by a radio receiver, producing voiced statements or other audible sounds indicative of the delivery of electrical stimulation. 10. The system of claim 9, wherein the implantable medical device is a cardiac pacemaker and the electrical stimulation comprises cardiac pacing pulses delivered to the patient's heart. 11. The system of claim 5, wherein the implantable medical device is a cardiac monitor that monitors the electrical activity of the patient's heart, further comprising: A device for detecting electrical activity of a patient's heart and providing a cardiac signal in response to the detected electrical activity; and wherein: the storage device stores at least one audio drive signal representing a cardiac signal; and the providing means provides an interrogation command which causes the retrieving means to retrieve stored audio drive signals representing the electrical activity of the heart detected each time the cardiac signal is provided, The radio frequency transmitter thereby broadcasts a modulated radio frequency signal that can be received and demodulated by the radio receiver, producing voiced statements or other audible sounds indicative of cardiac activity. 12. A method of interrogating implantable medical device information from an implantable medical device through a patient's body and transmitting the interrogated implantable medical device information to a radio receiver outside the patient's body, comprising the steps of: storing one or more audio drive signals, including voiced statements or other audible sounds, representing implantable medical device information within the implantable medical device; providing an interrogation signal from a location outside the patient's body to initiate interrogation of the implantable medical device; selecting one or more audio actuation signals for information on the implantable medical device according to the interrogation procedure; play a radio frequency signal modulated by a selected audio drive signal capable of being received and demodulated by a radio receiver to produce a spoken statement or other audible sound; and A voiced statement or other audible sound is received, demodulated and reproduced by a radio receiver. 13. The method of claim 12, wherein the plurality of audio drive signals associated with a particular portion of the medical device information is selected from a group of information, the group of information further comprising: medical device manufacturers; medical device identifier; patient identifier; date of implantation; date of last inquiry; stored physiological data; battery condition; real-time device operation; the currently programmed operating mode; the currently programmed operating parameter value; depletion of material reserves; device operation history; and The patient's testing status. 14. The method of claim 12, wherein the implantable medical device is powered by a battery, and the power of the battery is consumed by the implantable medical device, wherein; The storing step further includes storing at least one audio drive signal capable of being reproduced as a voiced statement or sound, conveying a battery power level; The providing step further includes providing a power level query command, causing the battery power level to be measured; The selecting step further includes selecting a stored audio drive signal indicative of the measured battery power level, The radio frequency transmitter thereby broadcasts a modulated radio frequency signal that can be detected and demodulated by the radio receiver, producing a voiced statement or other audible sound indicative of the battery charge level. 15. The method of claim 12, wherein the implantable medical device is a substance delivery system that releases substance from a dose of substance from a reservoir of defined volume to the patient's body, wherein; The step of storing includes storing an audio drive signal indicative of the amount of substance released or remaining in the reservoir; The step of providing further comprises providing a substance quantity query command which causes a measurement of the quantity of substance released or remaining in the reservoir; The selecting step includes selecting an audible actuation signal indicative of the amount of substance released or remaining in the reservoir, The radio frequency transmitter thereby plays a modulated radio frequency signal which can be detected and demodulated by the radio receiver, producing a voiced statement or other audible sound indicating what has been released or the amount of content remaining in the reservoir. 16. The method of claim 12, wherein the storing step further comprises the steps of: providing a memory having a memory location indicated by a memory address at which the audio drive signal is stored; and storing an audio drive signal comprising a voiced statement or an audible sound representing implantable medical device information at a specified memory address in the memory; and The step of selecting one or more audio drive signals for broadcast further comprises the steps of: memory addresses of one or more audio drive signals generating implantable medical device information in accordance with an interrogation procedure; and In response to the generated memory address, an audio drive signal is retrieved from the addressed memory location. 17. The method of claim 16, wherein the medical device information stored in the specified memory address with the audio drive signal is selected from a group of information, the group of information further comprising: medical device manufacturers; medical device identifier; patient identifier; date of implantation; date of last inquiry; stored physiological data; battery condition; real-time device operation; the currently programmed operating mode; the currently programmed operating parameter value; depletion of material reserves; device operation history; and The patient's testing status. 18. The method of claim 12, wherein the interrogation process includes performance of real-time device operation, and the at least one audio drive signal is indicative of real-time device operation of the implantable medical device, wherein: The storing step further includes storing an audio drive signal capable of being reproduced as a voiced statement or sound, conveying the performance of real-time device operation; The step of providing further includes providing a query command causing the real-time device operation to be performed; and The selecting step includes selecting an audio drive signal indicative of a performance of real-time device operation, The radio frequency transmitter thereby broadcasts a modulated radio frequency signal that can be detected and demodulated by the radio receiver, producing voiced statements or other audible sounds indicative of the performance of the device operation in real time. 19. The method of claim 18, wherein the real-time device operation and associated audio drive signals are selected from a group of information further comprising: monitor the patient's physiological condition; determine battery condition; and Give treatment to patients. 20. The method of claim 12, wherein the implantable medical device is an electrical stimulator for delivering electrical stimulation to body tissue of a patient, wherein: The step of storing includes storing an audio drive signal indicative of delivery of electrical stimulation to tissue of the patient; The providing step further comprises providing causing the selecting step to select the stored audio drive signal indicative of the delivery of electrical stimulation each time the electrical stimulation is delivered, The radio frequency transmitter thereby broadcasts a modulated radio frequency signal that can be detected and demodulated by a radio receiver, producing voiced statements or other audible sounds indicative of delivery of electrical stimulation. 21. The method of claim 20, wherein the implantable medical device is a cardiac pacemaker and the electrical stimulation comprises cardiac pacing pulses delivered to the patient's heart. 22. The method of claim 12, wherein the implantable medical device is a cardiac monitor that monitors the patient's electrical activity and provides a cardiac signal in response to the detected electrical activity, wherein: The storing step includes storing an audio drive signal representing a cardiac signal; The step of providing further includes providing causing the step of selecting to select a stored audio drive signal indicative of the detected electrical activity of the heart each time the cardiac signal is provided, The radio frequency transmitter thereby broadcasts a modulated radio frequency signal that can be detected and demodulated by a radio receiver, producing voiced statements or other audible sounds indicative of a cardiac signal. 23. A radio receiver that interrogates stored and real-time generated implantable medical device information of an implantable medical device implanted in a patient and broadcasts the interrogated implantable medical device information outside the patient's body through the patient's body A device system, characterized in that the system includes: a device located outside the patient's body and selectively operated by the healthcare provider and/or the patient to provide an interrogation signal to the implantable medical device to initiate an interrogation procedure for the implantable medical device; and Implantable medical devices further include: a memory storing at least one audio drive signal capable of being reproduced as voiced statements or audible sounds representing or conveying information about the medical device; a receiving device that receives the interrogation signal and starts the interrogation procedure; a readout device for reading information about the implantable medical device in accordance with an interrogation procedure in response to a received interrogation signal; a radio frequency transmitter for broadcasting a radio frequency signal modulated by an audio drive signal capable of being received and demodulated by a radio receiver located outside the patient's body; and Audio feedback means for retrieving from memory an audio drive signal associated with reading implantable medical device information and applying the retrieved audio drive signal to a radio frequency transmitter, causing the radio frequency transmitter to play a message conveying the readout implantable medical device A modulated radio frequency signal of device information whereby the radio frequency signal can be detected and demodulated by a radio receiver to produce a voiced statement or other audible sound. 24. The system of claim 23, wherein: a memory storing a plurality of audio drive signals associated with a particular portion of medical device information; and wherein: The readout means further includes means for retrieving a plurality of audio drive signals in a predetermined sequence; and The audio feedback means retrieves an audio drive signal in a predetermined sequence from the memory and applies the retrieved audio drive signal to the radio frequency transmitter, causing the radio frequency transmitter to play a modulated radio frequency signal conveying information to read the implantable medical device, whereby the Radio frequency signals can be detected and demodulated by radio receivers to produce voiced statements or other audible sounds. 25. The system of claim 24, wherein the plurality of audio drive signals associated with a particular portion of medical device information is selected from a group of information, the group of information further comprising: medical device manufacturers; medical device identifier; patient identifier; date of implantation; date of last inquiry; stored physiological data; battery condition; real-time device operation; the currently programmed operating mode; the currently programmed operating parameter value; depletion of material reserves; device operation history; and The patient's testing status. 26. The system of claim 23, wherein the interrogation program is capable of real-time device operation, and the audio drive signal stored in the memory represents real-time device operation of the implantable medical device, the implantable medical device further include: means for performing real-time device operations in response to the interrogation signal; and the means for audio feedback further comprising: means for generating memory addresses of audio drive signals associated with the performance of real-time device operation of the implantable medical device; and means, responsive to the generated memory address, for retrieving an audio drive signal from the memory and applying the retrieved audio drive signal to a radio frequency transmitter, causing the radio frequency transmitter to play a modulated radio frequency time-correlated to execution of real-time device operations Signals whereby voiced statements or audible sounds are generated by the radio receiver temporally correlated with the operation of the implantable medical device. 27. The system of claim 26, wherein the real-time device operation and associated audio drive signals stored in memory are selected from the group consisting of: monitor the patient's physiological condition; Determine battery condition; Give treatment to patients. 28. The system of claim 26, wherein the implantable medical device is a cardiac pacemaker, further comprising: A device for delivering pacing pulses to a patient's heart as a real-time operation; and wherein: a memory having a memory location indicated by a memory address storing an audio drive signal indicative of delivery of the pacing pulse; and The audio feedback device further includes: means responsive to pacing pulse delivery for selectively generating memory addresses of stored audio drive signals indicative of pacing pulse delivery; and means, responsive to the generated memory address, for retrieving an audio drive signal from the addressed memory location and applying the retrieved audio drive signal to a radio frequency transmitter, causing the radio frequency transmitter to play a radio capable of being detected and demodulated by a radio receiver A modulated radio frequency signal that produces voiced statements or other audible sounds that communicate the delivery of pacing pulses. 29. The system of claim 26, wherein the implantable medical device is a cardiac pacemaker, further comprising: A device that delivers pacing pulses to a patient's heart as a real-time operation; and As a means for sensing a cardiac event and providing a signal of the sensed event operating in real time, and wherein: The memory has memory locations represented by memory addresses at which a first audio drive signal indicative of delivery of a pacing pulse is stored and at a second memory address a second audio drive signal indicative of a sensed cardiac event is stored on; and The audio feedback device further includes: means responsive to delivery of a pacing pulse for selectively generating a first memory address of a stored first audio drive signal indicative of delivery of a pacing pulse; means responsive to the sensed event signal for selectively generating a second memory address indicative of the stored second audio drive signal of the sensed cardiac event; and means responsive to the generated first memory address and responsive to the generated second memory address, the former for retrieving an audio drive signal from the addressed memory location and applying the retrieved audio drive signal to the radio frequency transmitter, causing The radio frequency transmitter plays a modulated radio frequency signal that can be detected and demodulated by the radio receiver, producing a voiced statement or other audible sound that conveys the delivery of the pacing pulse; the latter is used to retrieve the audio drive signal from the addressed memory location and transfer the retrieved The received audio drive signal is applied to the radio frequency transmitter, causing the radio frequency transmitter to play a modulated radio frequency signal that can be detected and demodulated by the radio receiver, producing a voiced statement or other audible sound that conveys the sensed cardiac event relative to it in time. 30. The system of claim 26, wherein the implantable medical device is an electrical stimulator for delivering electrical stimulation to body tissue, further comprising: A device for delivering electrical stimulation to body tissue of a patient as an electrical stimulator operating in real time; and wherein: a memory having a memory location indicated by a memory address storing an audio drive signal indicative of delivery of the electrical stimulation; and The audio feedback device further includes: means responsive to delivery of electrical stimulation for selectively generating memory addresses of stored audio drive signals indicative of delivery of electrical stimulation; and means, responsive to the generated memory address, for retrieving an audio drive signal from the addressed memory location and applying the retrieved audio drive signal to a radio frequency transmitter, causing the radio frequency transmitter to play a radio capable of being detected and demodulated by a radio receiver A modulated radiofrequency signal that produces voiced statements or other audible sounds that communicate the delivery of electrical stimulation. 31. The system of claim 23, wherein the implantable medical device is a substance delivery system for delivering a substance from a reservoir of defined volume to a patient's body, further comprising: A device for delivering a dose of a substance from a reservoir of substance to the body of a patient; and wherein: a memory having a memory location indicated by a memory address, storing an audio drive signal indicative of the amount of content released or remaining in the memory; the interrogation signal providing means provides an interrogation command for the quantity of substance which causes a measurement of the quantity of substance released or remaining in the reservoir; and the audio feedback retrieval means retrieves and applies to the radio frequency transmitter a stored audio drive signal indicative of the quantity of substance released or remaining in the reservoir to be measured, The radio frequency transmitter thereby plays a modulated radio frequency signal which can be detected and demodulated by the radio receiver, producing a voiced statement or other audible sound indicating what has been released or the amount of content remaining in the reservoir.

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