CN118177955A - Grooved catheter with recessed flush hole - Google Patents

Abstract

Medical devices and methods of use thereof are disclosed. The medical device may include an elongate catheter body defining a longitudinal axis and a distal tip electrode coupled to a distal end of the elongate catheter body. The distal tip electrode may have an outer surface, a lumen, a proximal end, a distal end, and a wall having a plurality of apertures connecting the outer surface and the lumen, wherein the apertures are arranged in a grid. The wall of the distal tip electrode may have a plurality of longitudinal grooves and a plurality of circumferential grooves formed therein such that each longitudinal groove extends generally parallel to the longitudinal axis and has at least two apertures positioned with the respective longitudinal groove, and each circumferential groove intersects at least one of the longitudinal grooves to define an aperture at such intersection.

Description

Fluted catheter with recessed irrigation holes

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Patent Application No. 63/387,130, previously filed on December 13, 2022, which is hereby incorporated by reference in its entirety.

Technical Field

The present invention relates to devices for introducing media into the body. More particularly, the present invention relates to an ablation catheter having a side hole for fluid to pass therethrough.

Background technique

In some medical procedures, energy is applied locally to body tissue in concentrated doses, and it is desirable to cool the treated area to reduce collateral tissue damage.

A known difficulty in using radiofrequency energy to ablate cardiac tissue is controlling overheating of the tissue at the treatment site. There is a tradeoff between the desire to create a large enough ablation lesion to effectively ablate abnormal tissue or block abnormal conduction patterns and the undesirable effects of overheated areas near the treatment site. If the radiofrequency device forms an ablation lesion that is too small, the medical procedure may not be very effective or may require too much time. On the other hand, if the tissue is overheated, there may be localized charring effects, coagulants, and steam explosions caused by overheating. Such overheated areas may form high impedance and may form a functional barrier to heat pathways. Using slower heating provides better control of ablation, but unduly prolongs the procedure.

It has been found that cooling the ablation site area reduces tissue charring and thrombosis. To this end, Biosense Webster Inc. (Diamond Bar, California) provides Irrigated tip catheter as part of its integrated ablation system. The metal catheter tip powered with RF current to ablate the tissue has multiple peripheral holes distributed around the tip circumference for irrigating the treatment site. A pump connected to the catheter delivers saline solution to the catheter tip, and the solution flows out through the holes during the procedure, cooling the catheter tip and tissue.

For example, U.S. Pat. No. 8,517,999 to Pappone et al. describes an irrigation catheter having uniform cooling and/or uniform fluid distribution in longitudinally spaced elution holes by varying the diameter of the fluid delivery lumen. A plurality of elution holes are provided in the tip region of the catheter body and are in fluid communication with the lumen through tubing.

Summary of the invention

The present invention discloses a medical device and a method for using the same. The medical device may include an elongated catheter body defining a longitudinal axis and a distal tip electrode coupled to the distal end of the elongated catheter body. The distal tip electrode may have an outer surface, a cavity, a proximal end, a distal end, and a wall having a plurality of orifices connecting the outer surface and the cavity, wherein the orifices are arranged in a grid. The wall of the distal tip electrode may have a plurality of longitudinal grooves and a plurality of circumferential grooves formed in the wall, so that each longitudinal groove extends approximately parallel to the longitudinal axis and has at least two orifices positioned with the corresponding longitudinal groove, and each circumferential groove intersects with at least one of the longitudinal grooves to define an orifice at such an intersection.

One aspect of the invention described herein provides a medical device. The medical device may include an elongated catheter body defining a longitudinal axis. The medical device may include a distal tip electrode coupled to the distal end of the elongated catheter body. The distal tip electrode may have an outer surface, a cavity, a proximal end, a distal end, and a wall having a plurality of orifices connecting the outer surface and the cavity. The orifices may be arranged in the form of a grid having columns substantially parallel to the longitudinal axis and rows substantially perpendicular to the longitudinal axis. The medical device may include a plurality of longitudinal grooves formed in the wall of the distal tip electrode, such that each longitudinal groove extends substantially parallel to the longitudinal axis. Each longitudinal groove in the plurality of longitudinal grooves may have at least two orifices in the plurality of orifices positioned in the corresponding longitudinal groove. The medical device may include a first plurality of circumferential grooves formed in the wall of the distal tip electrode, such that each circumferential groove intersects with at least one of the longitudinal grooves to define an orifice at such an intersection.

According to some embodiments, the medical device may further include one or more sensing elements disposed on the distal end of the distal tip electrode. Each of the one or more sensing elements may be positioned between two adjacent longitudinal grooves.

According to some embodiments, each of the plurality of apertures can be recessed from the outer surface of the distal tip electrode by a distance D. According to some embodiments, the distance D can be between approximately 0.05 mm and 0.02 mm.

According to some embodiments, a first portion of the plurality of apertures can be oriented at a proximal angle relative to the longitudinal axis.The first portion can be positioned in a row proximal to a proximal end of the distal tip electrode.

According to some embodiments, a second portion of the plurality of apertures is oriented at a distal angle relative to the longitudinal axis.The second portion may be positioned in a row proximate a distal end of the distal tip electrode.

According to some embodiments, the aperture may be configured to direct an irrigation fluid.

According to some embodiments, the first plurality of circumferential grooves may have at least two apertures positioned in respective non-adjacent rows within respective circumferential grooves of the first plurality of circumferential grooves.

According to some embodiments, a plurality of longitudinal grooves may have four apertures positioned within a respective longitudinal groove.

According to some embodiments, the plurality of longitudinal grooves and the first plurality of circumferential grooves may form a grid pattern on the wall of the distal tip electrode.

According to some embodiments, the medical device may further include a fluid guiding assembly having an axial channel that is fluidly connected to the cavity of the distal tip electrode and thereby fluidly connected to a plurality of orifices. The medical device may further include a blocking terminal fixed in the cavity of the distal tip electrode. The blocking terminal may be configured to block the flow of the fluid in the longitudinal direction and guide the flow of the fluid through at least one cross-axial channel transverse to the axial channel and guide the flow of the fluid through the plurality of orifices. According to some embodiments, the fluid guiding assembly may have between two and twelve cross-axial channels. According to some embodiments, the fluid guiding assembly may have exactly one cross-axial channel.

According to some embodiments, the distal tip electrode may include at least one electrode coupled to an energy source to apply an ablative current to tissue. The fluid directing assembly may be in fluid communication with an irrigation pump that delivers irrigation fluid to the fluid directing assembly, and in response to increasing the power to the at least one electrode to approximately 90 W, the medical device may increase an irrigation flow rate of the irrigation pump. According to some embodiments, the irrigation flow rate may be increased by closing a circuit with the irrigation pump.

In another aspect, a medical device is disclosed. The medical device may include an elongated catheter body defining a longitudinal axis. The medical device may include a distal tip coupled to a distal end of the elongated catheter body. The distal tip may have an outer surface, a cavity, a proximal end, a distal end, and a wall having a plurality of orifices connected to the outer surface and the cavity. The distal tip may include at least one electrode coupled to an energy source. The electrode may be configured to apply an ablation current to tissue in a patient. The wall of the distal tip may have a first plurality of grooves formed in the wall. Each groove in the first plurality of grooves may be formed in a first orientation relative to the longitudinal axis. The wall of the distal tip may include a second plurality of grooves formed in the wall. The second plurality of grooves may be formed in a second orientation relative to the longitudinal axis. Each of the first plurality of grooves and the second plurality of grooves may have at least two corresponding orifices of a plurality of orifices positioned within the corresponding groove. The medical device may include a fluid guiding assembly. The fluid guiding assembly may have an axial channel in fluid communication with the cavity of the distal tip and thereby in fluid communication with the plurality of orifices. The medical device may also include a blocking terminal fixed in the cavity of the distal tip. The choke terminal may be configured to choke the flow of fluid in the longitudinal direction and direct the flow of fluid through at least one cross-axial passage transverse to the axial passage.

According to some embodiments, the first plurality of grooves and the second plurality of grooves can each form a diagonal groove in the wall of the distal tip relative to the longitudinal axis.

According to some embodiments, the first plurality of grooves and the second plurality of grooves may be arranged in the wall of the distal tip in the form of a grid pattern of grooves.

According to some embodiments, the first plurality of grooves and the second plurality of grooves can be arranged in a random pattern in the wall of the distal tip.

According to some embodiments, a medical device may include one or more sensing elements disposed on a distal tip.

According to some embodiments, the fluid directing assembly can be in fluid communication with an irrigation pump that delivers irrigation fluid to the fluid directing assembly. In response to increasing the power of the at least one electrode to about 90 W, the medical device can increase an irrigation flow rate of the irrigation pump.

According to some embodiments, each of the plurality of apertures can be recessed from the outer surface of the distal tip by a distance D. According to some embodiments, the distance D can be between approximately 0.05 mm and 0.2 mm.

According to some embodiments, a first portion of the plurality of orifices may be oriented at a proximal angle relative to the longitudinal axis. The first portion of the plurality of orifices may be positioned in a row near the proximal end of the distal tip. According to some embodiments, a second portion of the plurality of orifices may be oriented at a distal angle relative to the longitudinal axis. The second portion of the orifices in the plurality of orifices may be positioned in a row near the distal end of the distal tip.

According to some embodiments, the aperture may be configured to direct irrigation fluid to tissue within the body.

In another aspect, a method of directing an irrigation fluid from a medical probe is disclosed. The method may include providing a probe having an elongated catheter body defining a longitudinal axis, a distal tip coupled to a distal end of the elongated catheter body, and a fluid directing assembly having an axial channel in fluid communication with a cavity within the distal tip and a plurality of orifices connecting an outer surface of the distal tip to the cavity. The distal tip may have an outer surface, a cavity, a proximal end, a distal end, and a wall having a plurality of orifices connecting the outer surface and the cavity. The orifices may be arranged in a grid having columns generally parallel to the longitudinal axis and rows generally perpendicular to the longitudinal axis. The wall may have a plurality of longitudinal grooves and a plurality of circumferential grooves. The distal tip may include at least one electrode coupled to an energy source that may be configured to apply an ablation current to tissue. The method may include providing an irrigation fluid into an axial channel of the fluid directing assembly. The method may include directing the irrigation fluid from the axial channel through one or more cross-axial channels perpendicular to the axial channel, through the cavity of the electrode, and through the plurality of orifices into the tissue. The method may include directing the irrigation fluid from the plurality of apertures through the plurality of longitudinal grooves and the plurality of circumferential grooves.

According to some embodiments, a first portion of the plurality of orifices may be oriented at a proximal angle relative to the longitudinal axis. The first portion of the plurality of orifices may be positioned in a row near the proximal end of the distal tip. According to some embodiments, a second portion of the plurality of orifices may be oriented at a distal angle relative to the longitudinal axis. The second portion of the plurality of orifices may be positioned in a row near the proximal end of the distal tip.

According to some embodiments, each of the plurality of apertures can be recessed from the outer surface of the distal tip by a distance D. According to some embodiments, the distance D is between about 0.05 mm and about 0.2 mm.

According to some embodiments, the method may include pressing the distal tip against tissue until a wall of the distal tip is pressed against the tissue and allows irrigation fluid to flow through the plurality of apertures without becoming obstructed due to each of the plurality of apertures being recessed from an outer surface of the distal tip.

BRIEF DESCRIPTION OF THE DRAWINGS

The above aspects and additional aspects of the present invention will be further discussed with reference to the following description and in conjunction with the accompanying drawings, in which like numbers indicate similar structural elements and features in the various figures. The accompanying drawings are not necessarily drawn to scale, but instead, emphasis is placed on illustrating the principles of the present invention. The accompanying drawings depict one or more specific implementations of the present invention by way of example only and not by way of limitation.

FIG. 1 is an illustration of cardiovascular treatment utilizing a catheter in accordance with aspects of the present invention.

2A is an illustration of a distal end portion of a catheter according to aspects of the present invention.

2B is a graphical representation of the angular offset and countersunk depth of an aperture formed in the wall of a distal end portion of a catheter, in accordance with aspects of the present invention.

3 is a longitudinal section view of the distal end portion shown in FIG. 2A , according to aspects of the present invention.

4 is a cross-sectional view showing a distal section of a catheter showing a fluid directing assembly according to aspects of the present invention.

5 is an oblique view of the fluid directing assembly shown in FIG. 4 according to aspects of the present invention.

6 is an oblique view of the distal end of a catheter according to aspects of the present invention.

7 is an oblique view of the fluid directing assembly shown in FIG. 4 according to aspects of the present invention.

8 is a cross-sectional view showing a distal section of a catheter showing a fluid directing assembly according to aspects of the present invention.

9 is a flow chart of an exemplary method of treating a patient using a catheter according to aspects of the present invention.

Detailed ways

The following description of certain examples of the present invention should not be used to limit the scope of the present invention. The accompanying drawings (not necessarily drawn to scale) depict selected embodiments and are not intended to limit the scope of the present invention. The detailed description illustrates the principles of the present invention by way of example and not by way of limitation. From the following description, other examples, features, aspects, embodiments and advantages of the present invention will become apparent to those skilled in the relevant art, and the following description is by way of example, which is one of the best ways contemplated for implementing the present invention. As will be appreciated, the present invention can have other different or equivalent aspects, all of which do not depart from the present invention. Therefore, the drawings and description should be considered to be illustrative and not restrictive in nature.

Any one or more of the teachings, expressions, patterns, examples, etc. described herein may be combined with any one or more of the other teachings, expressions, patterns, examples, etc. described herein. Therefore, the following teachings, expressions, patterns, examples, etc. should not be considered separate from each other. With reference to the teachings herein, various suitable ways in which the teachings herein may be combined will be apparent to those skilled in the relevant art. Such modifications and variations are intended to be included within the scope of the claims.

As used herein, the term "about" or "approximately" for any numerical value or range indicates a suitable dimensional tolerance that allows a collection of parts or components to achieve its intended purpose as described herein. More specifically, "about" or "approximately" can refer to a range of ±10% of the value of the recited value, for example, "about 90%" can refer to a range of values from 81% to 99%. In addition, as used herein, the terms "patient", "host", "user" and "subject" refer to any human or animal subject, and are not intended to limit the system or method to human use, but the use of the subject invention in human patients represents a preferred embodiment.

As shown in FIG. 1 , system 10 can be used to assess electrical activity and perform an ablation procedure on a heart 12 of a living subject, the ablation procedure being constructed and operated in accordance with a disclosed embodiment of the present invention. The system includes a catheter 14 that is inserted percutaneously through the patient's vascular system into a chamber or vascular structure of the heart 12 by an operator 16. The operator 16, who is typically a physician or medical professional, brings the distal tip 18 of the catheter into contact with the heart wall, for example, at an ablation target site. Electrical activity maps can be prepared according to the methods disclosed in U.S. Patents 6,226,542 and 6,301,496, commonly assigned U.S. Patent 6,892,091, and U.S. Patent Publication No. 2021/0282848, the disclosures of which are incorporated herein by reference and are attached as an appendix to priority patent application No. 63/387,130. A commercial product comprising elements of system 10 is provided in the form of a The 3 system was purchased from Biosense Webster, Inc. (3333 Diamond Canyon Road, Diamond Bar, California 91765). This system can be modified by one skilled in the art to implement the principles of the invention described herein.

Ablation can be performed by applying thermal energy to areas determined to be abnormal, for example, by evaluation of electrical activity mapping, for example, by conducting radiofrequency current through wires in the catheter to one or more electrodes at the distal tip 18, which apply radiofrequency energy to the myocardium. The energy is absorbed in the tissue, heating the tissue to a temperature (typically about 50° C.) at which the tissue permanently loses its electrical excitability. When successful, the procedure forms non-conductive lesions in the heart tissue that interrupt the abnormal electrical pathways that cause the arrhythmia. The principles of the present invention can be applied to different chambers of the heart to diagnose and treat a variety of different arrhythmias.

The catheter 14 generally includes a handle 20 having suitable controls thereon to enable the operator 16 to steer, position and orient the distal end of the catheter as desired for ablation. To assist the operator 16, the distal portion of the catheter 14 includes a position sensor (not shown) that provides signals to a processor 22 located in a console 24. The processor 22 may perform several processing functions as described below.

Ablation energy and electrical signals may be transmitted back and forth between the heart 12 and the console 24 via the cable 34 through one or more ablation electrodes 32 located at or near the distal tip 18. Pacing signals and other control signals may be transmitted from the console to the heart 12 via the cable 34 and electrodes 32. Sensing electrodes 33, which are also connected to the console 24, are disposed between the ablation electrodes 32 and have connections to the cable 34.

The lead connector 35 links the console 24 with the body surface electrodes 30 and other components of the positioning subsystem for measuring the position and orientation coordinates of the catheter 14. The processor 22 or another processor (not shown) can be an element of the positioning subsystem. The electrodes 32 and the body surface electrodes 30 can be used to measure tissue impedance at the ablation site, as taught in U.S. Patent No. 7,536,218 to Govari et al., which is incorporated herein by reference in its entirety as if fully set forth and attached in the appendix to priority patent application No. 63/387,130. A sensor for bioelectric information (e.g., a temperature sensor (not shown) (typically a thermocouple or thermistor)) can be mounted on or near each of the electrodes 32.

The console 24 typically includes one or more ablation power generators 25. The catheter 14 may be adapted to conduct ablation energy to the heart using any known ablation technique, such as radiofrequency energy, ultrasound energy, and laser-generated light energy. Such methods are disclosed in commonly assigned U.S. Patents 6,814,733, 6,997,924, and 7,156,816, which are incorporated herein by reference and are attached as an appendix to priority patent application No. 63/387,130.

In one embodiment, the positioning subsystem may include a magnetic positioning tracking arrangement that uses magnetic field generating coils 28 to determine the position and orientation of the catheter 14 by generating magnetic fields at a predetermined working volume and sensing these magnetic fields at the catheter. The positioning subsystem is described in U.S. Patent No. 7,756,576, which is incorporated herein by reference, and in the appendix to priority patent application No. 63/387,130.

As described above, the catheter 14 is coupled to a console, which enables the operator 16 to observe and regulate the functions of the catheter 14. The console 24 includes a processor, preferably a computer with appropriate signal processing circuits. The processor is coupled to drive the monitor 29. These signal processing circuits typically receive, amplify, filter and digitize signals from the catheter 14, including signals generated by sensors such as electrical sensors, temperature sensors and contact force sensors, and a plurality of position sensing electrodes (not shown) located distal to the catheter 14. The digitized signals are received and used by the console 24 and the positioning system to calculate the position and orientation of the catheter 14 and to analyze the electrical signals from the electrodes.

To generate the electroanatomical map, processor 22 typically includes an electroanatomical map generator, an image registration program, an image or data analysis program, and a graphical user interface configured to present graphical information on monitor 29 .

Typically, the system 10 includes other elements, but they are not shown in the drawings for simplicity. For example, the system 10 may include an electrocardiogram (ECG) monitor that is connected to receive signals from one or more body surface electrodes to provide an ECG synchronization signal to the console 24. As described above, the system 10 also typically includes a reference position sensor that is either located on an externally applied reference patch attached to the outside of the subject's body or on an internal catheter inserted into the heart 12 and maintained in a fixed position relative to the heart 12. A conventional pump and tubing are provided for circulating fluid through the catheter 14 to cool the ablation site. The system 10 can receive image data from an external imaging modality such as an MRI unit and include an image processor that can be incorporated into the processor 22 or called by the processor 22 for generating and displaying images.

Reference is now made to FIG. 2A , which is a view of a distal end portion 37 of a catheter 39 suitable for cardiac ablation according to aspects of the present invention. The distal end portion 37 is typically a hollow cylinder having a typical diameter of 2.5 mm. The tip 41 may be conductive and serves as an ablation electrode linked to an RF current generator. Typically, during ablation, heat is generated by resistive heating of the tissue. The heat is conducted to the surrounding area including the ablation electrode. In order to dissipate the heart and dilute the surrounding blood, an irrigation orifice 43 or hole is formed in the distal end portion 37. The orifice 43 typically has a diameter in the range of about 0.05 mm to 0.2 mm. The irrigation fluid may be supplied by an internal catheter (not shown) extending through the lumen of the catheter 39. The flow rate of the irrigation fluid is controlled by the irrigation module and may vary between about 2 cc to about 30 cc per minute, but may be higher or lower than this range. A flow rate of 15 cc per minute is suitable for high flow requirements. The temperature surrounding the distal end portion 37 can be controlled by varying either or both the flow rate and temperature of the irrigation fluid in accordance with the teachings of commonly assigned U.S. Patent Nos. 10,327,859, 9,956,035, and 9,737,353, which are incorporated herein by reference and are attached as appendices to priority patent application No. 63/387,130.

As can be seen in FIG. 2A , the distal end portion 37 of the catheter 39 may include one or more thermocouples 46 located at the tip 41 of the distal end portion 37. The thermocouple 46 may be any sensor suitable for obtaining electrophysiological data from the body, such as a temperature sensor for monitoring tissue ablation. In addition, the distal end portion 37 may include a plurality of grooves 44A oriented in a first direction (e.g., in a longitudinal direction) and a plurality of grooves 44B oriented in a second direction (e.g., in a circumferential direction). The plurality of grooves may be used for the purpose of improving the distribution of irrigation fluid to the tissue site during the ablation procedure, thereby avoiding the formation of hot spots that allow "steam pops" that may damage tissue surrounding the ablation site. According to some embodiments, the first plurality of grooves (e.g., longitudinal grooves 44A) extend generally parallel to the longitudinal axis defined by the catheter 39, and each longitudinal groove 44A may have at least two orifices 43 positioned within the corresponding longitudinal groove 44A, thereby facilitating redistribution of irrigation fluid along the outer surface of the distal end portion 37 and the tissue ablation site. According to some embodiments, each groove in the second plurality of grooves (e.g., circumferential grooves 44B) may intersect at least one of the longitudinal grooves 44A to define an orifice 43 at such intersection. According to some embodiments, the plurality of grooves 44 may be implemented in any geometric configuration. For example, the plurality of grooves 44A, 44B may form a grid pattern, a diagonal pattern, and/or a random pattern. FIG. 2A shows an embodiment in which the first plurality of grooves 44A extends in the longitudinal direction and the second plurality of grooves 44B extends in the circumferential direction.

An exemplary orifice 43 can be seen in more detail with reference to FIG. 2B . As shown in FIG. 2B , the orifice 43 can be offset from the normal PP of the surface of the distal end portion 37 extending from the catheter 39. The offset angle of the orifice 43 can be between β ₁ in a first direction (e.g., proximal direction) relative to the catheter 39 and β ₂ in a second direction (e.g., distal aspect) relative to the catheter 39. According to some embodiments, the angle β ₁ can be between about 5 degrees and about 15 degrees. According to some embodiments, the angle β ₂ can be between about 5 degrees and about 15 degrees. In addition, the orifice 43 can be offset from the surface S of the catheter distal end portion 37 by a distance D. According to some embodiments, the orifice 43 can be buried in the surface S of the catheter distal end portion 37 so as to space the orifice 43 from the surface of the tissue, thereby increasing the irrigation efficiency and reducing hot spots during the ablation procedure. A first (e.g., left) countersunk hole angle φ ₁ and a second (e.g., right) countersunk hole angle φ ₂ are provided. According to some embodiments, the countersink angles φ ₁ , φ ₂ may be between about 15 degrees and about 45 degrees, whereas in other embodiments, the orifice 43 has no countersink angles φ ₁ , φ ₂ . According to some embodiments, the distance D may be any convenient distance that separates the orifice 43 from the tissue surface of a patient undergoing an ablation medical procedure. However, in a preferred embodiment, the distance D may be measured between about 0.05 mm and 0.5 mm. The countersink defined by the angles φ ₁ , φ ₂ may be used to increase the surface diameter of the orifice 43, which increases the force that needs to be applied to the distal catheter end portion 37 against the tissue before the orifice is blocked by the tissue surface. Thus, the countersink improves the efficiency of flushing through the orifice 43 during an ablation procedure.

FIG. 3 shows a longitudinal partial cross-sectional view of the distal end portion 37 of the catheter 39 according to an embodiment of the present invention. The distal end portion 37 includes a hollow electrode 47 having a lumen 49 (as can be better seen in FIG. 4 ). The lumen 49 is partially occupied by a fluid delivery assembly 51. The distal end portion 37 has a longitudinal symmetry axis 53. Orifices 57, 59 and other orifices 43 ( FIG. 2A ) are formed inside the wall 55 of the electrode 47. The orifices connect the outside of the electrode 47 to the lumen 49 fluid having a channel (e.g., channel 61). The channel 61 points outward and backward. For the purposes of this disclosure, the term "rearward" refers to a direction from the distal tip 63 generally toward the proximal end 65 of the distal end portion 37. The term "outward" refers to a direction generally away from the symmetry axis 53. The longitudinal axes 67, 69 of the orifices 57, 59 intersect the symmetry axis 53 at angles of incidence θ ₁ and θ ₂ , respectively. The angle of incidence of the outward, rearwardly directed aperture with the axis of symmetry 53 may vary from about 5 degrees to about 75 degrees, and is optimally about 45 degrees.

An irrigation fluid is delivered under pressure from an external source through the catheter into the assembly 51. The irrigation fluid may exit the assembly 51 into the lumen 49 of the electrode 47. The irrigation fluid then exits the lumen 49 via the orifices 57, 59 in the direction indicated by the arrows along the axes 67, 69. The irrigation fluid so directed cools the area obliquely rearward and outboard of the distal end portion 37. Similarly, the outwardly, forwardly directed orifices 71, 73 direct the irrigation fluid in a direction specified by the angle of their respective channels 75 relative to the axis of symmetry 53 (e.g., the angle of incidence θ ₃ in the case of orifice 73) to deliver the fluid obliquely forward and outward from the distal end portion 37. In addition, the distal end portion 37 may include conventional lateral orifices, such as orifices 77, 79, which direct the irrigation fluid outwardly and laterally from the distal end portion 37. The inclusion of the grooves 44A, 44B in the surface of the distal end portion 37 facilitates optimal distribution of the irrigation fluid throughout the ablation site and the area proximal to the ablation site during the medical procedure. The grooves prevent hot spots from forming around the treatment site and reduce the incidence of "steam pops" that can damage surrounding tissue.

A cross-sectional view of the distal end portion 37 of the catheter 39 according to an embodiment of the present invention is shown in FIG4. An assembly 51 cooperates with the segment 81 of the catheter 39 and the electrode 47. The assembly 51 includes an axial lumen 83 that conducts irrigation fluid distally toward a blocking terminal 85 that prevents the irrigation fluid from continuing in a forward direction. The flow of irrigation fluid is indicated by arrows 87. At the terminal 85, a plurality of channels 89 branch outwardly across the axial direction at 90° angles from the axial lumen 83, thereby shunting the flow outward as shown by arrows 91. The irrigation fluid enters the lumen 49 transverse to the axis of the catheter 39, generally toward lateral channels in the electrode 47, such as channel 61.

If the irrigation path exited lumen 83 aligned with axis of symmetry 53 (as shown in FIG. 3 ), irrigation flow through channel 61 would be disadvantageous because the flow would be required to reverse course and turn more than 90 degrees to enter a proximally angled channel, such as channel 61. An advantage of the arrangement of FIG. 4 is that the irrigation flow is relatively more evenly distributed to all of the apertures in electrode 47 than if the flow exited assembly 51 in a forward direction.

FIG5 shows an oblique view of assembly 51 showing channels 89 according to an embodiment of the present invention. In this embodiment, there are three channels 89 located in plane 93 and distributed at 120° angles around the axis of the catheter. The direction of flow out of the assembly 51 from the lumen 83 is indicated by the dashed line 95. Other embodiments may have different numbers of channels 89, typically varying between two and twelve channels.

Referring now to FIG. 6 , which is an oblique view of the distal end of catheter 111 according to an alternative embodiment of the present invention. Assembly 113 is disposed within electrode 47. In addition to the fluid diversion function described above, assembly 113 also has a second function of supporting sensor 115 through slot 117. The sensor may be any sensor suitable for obtaining electrophysiological data from the body, such as a temperature sensor for monitoring tissue ablation. Slot 117 allows the sensor to pass through assembly 113 into the wall cavity of electrode 47. In operation, when the catheter is located in the heart, different sensors can be inserted through the catheter through slot 117 and retracted as required by the medical procedure.

FIG7 shows an oblique view of an assembly 119 according to an alternative embodiment of the present invention. FIG7 is similar to FIG5, except that FIG7 shows a single transaxial channel 121 forming a slot extending around a sector of the circumference of the lumen 83, which sector may be 360 degrees as shown in FIG7. As shown in FIG7, there may be one slot. Alternatively, more than one slot may be distributed around the circumference of the assembly.

FIG8 shows yet another alternative embodiment of the present invention. In FIG8, a single gap provides flow transverse to the axis of symmetry with a full 360 degree expansion. FIG8 shows a cross-sectional view of the distal end portion 124 of a catheter 125 according to an alternative embodiment of the present invention. Assembly 127 cooperates with segment 81 of catheter 125 and electrode 47. Unlike the embodiment shown in FIG4, assembly 127 does not contain channel 89 and blocking terminal 85. Instead, the flow leaves the distal end of assembly 127 and continues distally within lumen 49, striking baffle 129, which is separated from assembly 127 by gap 133. Baffle 129 deflects the flow of irrigation fluid transverse to the axis of symmetry toward the wall of electrode 47 with a 360 degree radial expansion, as shown by arrow 131. Thereafter, the irrigation fluid enters channel 61 and other channels that penetrate the wall of electrode 47, as described in more detail with respect to FIG4.

FIG. 9 is a flow chart of an exemplary method 900 for treating a patient using a catheter according to aspects of the present invention. In box 902, the method includes providing a probe. The probe may have an elongated catheter body defining a longitudinal axis and a distal tip connected to the distal end of the elongated catheter body. The distal tip may have an outer surface, a cavity, a proximal end, a distal end, and a wall having a plurality of orifices 43 connecting the outer surface and the cavity. The orifices may be arranged in a grid having columns substantially parallel to the longitudinal axis and rows substantially perpendicular to the longitudinal axis. The wall of the distal tip may have a plurality of longitudinal grooves 44A and a plurality of circumferential grooves 44B. The distal tip may include at least one electrode coupled to an energy source to apply an ablation current to the tissue. The probe may also include a fluid guide assembly having an axial channel, the axial channel being in fluid communication with the cavity of the distal tip, and thereby being in fluid communication with a plurality of orifices.

In frame 904, the method may include providing an irrigation fluid into the axial channel of the fluid directing assembly. In frame 906, the method may include directing the irrigation fluid from the axial channel through one or more cross-axial channels perpendicular to the axial channel, through the lumen of the electrode 47, and into the tissue through the plurality of orifices 43. In frame 908, the method may include directing the irrigation fluid from the plurality of orifices 43 through the plurality of longitudinal grooves 44A and the plurality of circumferential grooves 44B. In frame 910, the method may include pressing the distal tip 41 against the tissue until the wall 55 of the distal tip is pressed against the tissue. In frame 912, the method may include flowing the irrigation fluid through the plurality of orifices 43 without becoming blocked due to each of the plurality of orifices 43 being recessed from the outer surface of the distal tip 41.

In some embodiments, a first portion of the plurality of apertures is oriented at a proximal angle relative to the longitudinal axis, and the first portion may be positioned on a row of apertures near the proximal end of distal tip 41. For example, the angled apertures may provide improved irrigation fluid flow to an area near the proximal end of distal tip 41. In some embodiments, the proximal angle may be between about 5 degrees and about 15 degrees.

In some embodiments, a second portion of the plurality of orifices may be oriented at a distal angle relative to the longitudinal axis. The second portion of the orifices may be positioned in a row near the distal end of the distal tip 41. For example, the angled orifices may provide improved irrigation fluid flow to an area near the proximal end of the distal tip 41. In some embodiments, the distal angle may be between about 5 degrees and about 15 degrees.

In some embodiments, each of the plurality of apertures can be recessed a distance D from the outer surface of distal tip 41. The distance D can be between approximately 0.05 mm and 0.2 mm.

It should be understood by those skilled in the relevant art that the present invention is not limited to the contents specifically shown and described herein. On the contrary, the scope of the present invention includes both the combination and sub-combination of the various features described herein, as well as the variations and modifications of the above various features that are not within the scope of the prior art that the relevant art technicians may think of when reading the above description.

The following clauses set forth non-limiting embodiments of the present disclosure:

Item 1: A medical device comprising: an elongated catheter body defining a longitudinal axis; a distal tip electrode coupled to a distal end of the elongated catheter body, the distal tip electrode having an outer surface, a cavity, a proximal end, a distal end, and a wall, the wall having a plurality of orifices connecting the outer surface and the cavity, the orifices being arranged in a grid having columns generally parallel to the longitudinal axis and rows generally perpendicular to the longitudinal axis; a plurality of longitudinal grooves formed in the wall of the distal tip electrode such that each longitudinal groove extends generally parallel to the longitudinal axis, each of the plurality of longitudinal grooves having at least two of the plurality of orifices positioned within the respective longitudinal grooves; and a first plurality of circumferential grooves formed in the wall of the distal tip electrode such that each circumferential groove intersects with at least one of the longitudinal grooves to define an orifice at such intersection.

Clause 2: The medical device of clause 1, further comprising one or more sensing elements disposed on the distal end of the distal tip electrode, each sensing element of the one or more sensing elements being positioned between two adjacent longitudinal grooves.

Clause 3: The medical device of clause 1 or 2, each of the plurality of apertures being recessed a distance D from an outer surface of the distal tip electrode.

Clause 4: The medical device of clause 3, wherein the distance D is between about 0.05 mm and about 0.2 mm.

Clause 5: The medical device of any of clauses 1 to 4, wherein a first portion of the plurality of apertures is oriented at a proximal angle relative to the longitudinal axis, the first portion being positioned in a row proximal to the proximal end of the distal tip electrode.

Clause 6: The medical device of any of clauses 1 to 5, wherein a second portion of the plurality of apertures is oriented at a distal angle relative to the longitudinal axis, the second portion being positioned in a row proximate the distal end of the distal tip electrode.

Clause 7: The medical device of any one of clauses 1 to 6, the aperture being configured to direct an irrigation fluid.

Clause 8: The medical device of any of clauses 1 to 7, at least one circumferential groove of the first plurality of circumferential grooves having at least two apertures positioned in respective non-adjacent rows within the respective circumferential groove of the first plurality of circumferential grooves.

Clause 9: The medical device of any of clauses 1 to 8, the plurality of longitudinal grooves having four apertures of the plurality of apertures positioned within the respective longitudinal grooves.

Clause 10: The medical device of any of clauses 1 to 9, the plurality of longitudinal grooves and the first plurality of circumferential grooves forming a grid pattern on the wall of the distal tip electrode.

Clause 11: The medical device according to any one of clauses 1 to 10, further comprising:

a fluid directing assembly having an axial passage in fluid communication with the lumen of the distal tip electrode and thereby in fluid communication with the plurality of orifices; and

A blocking terminal is fixed in the cavity of the distal tip electrode, and the blocking terminal is configured to block the flow of fluid along the longitudinal axis, guide the flow of fluid through at least one cross-axial channel transverse to the axial channel, and guide the flow of fluid through the plurality of orifices.

Clause 12: The medical device of clause 11, the fluid directing assembly having between two and twelve trans-axial channels.

Clause 13: The medical device of clause 11, wherein the fluid directing assembly has exactly one transaxial channel.

Item 14: According to the medical device of Item 11, the distal tip electrode includes at least one electrode, the at least one electrode is connected to an energy source to apply an ablation current to the tissue; the fluid guiding assembly is fluidly connected to an irrigation pump, the irrigation pump delivers irrigation fluid to the fluid guiding assembly; and in response to increasing the power of the at least one electrode to approximately 90W, the irrigation flow rate of the irrigation pump is increased.

Clause 15: The medical device of clause 14, wherein the irrigation flow rate is increased by closing the circuit with the irrigation pump.

Item 16: A medical device comprising: an elongated catheter body defining a longitudinal axis; a distal tip coupled to a distal end of the elongated catheter body, the distal tip having an outer surface, a cavity, a proximal end, a distal end, and a wall, the wall comprising an end portion and a side wall portion, the side wall portion of the wall having a plurality of openings connecting the outer surface and the cavity; the distal tip comprising at least one electrode coupled to an energy source to apply an ablation current to tissue within a patient; a first plurality of grooves formed in the wall of the distal tip, each of the first plurality of grooves being formed in a first orientation relative to the longitudinal axis; a second plurality of grooves, the A second plurality of grooves are formed in the wall of the distal tip, the second plurality of grooves being formed in a second orientation relative to the longitudinal axis; each of the first plurality of grooves and the second plurality of grooves having at least two corresponding orifices of the plurality of orifices positioned within the corresponding groove; a fluid directing assembly having an axial channel fluidly connected to the cavity of the distal tip and thereby fluidly connected to the plurality of orifices; and a blocking terminal fixed in the cavity of the distal tip, the blocking terminal being configured to block the flow of fluid along the longitudinal axis, direct the flow of fluid through at least one cross-axial channel transverse to the axial channel, and direct the flow of fluid through the plurality of orifices.

Clause 17: The medical device of clause 16, the first plurality of grooves and the second plurality of grooves each forming a diagonal groove in the wall of the distal tip relative to the longitudinal axis.

Clause 18: The medical device of Clause 16, the first plurality of grooves and the second plurality of grooves being arranged in the wall of the distal tip in a grid pattern of grooves.

Clause 19: The medical device of Clause 16, the first plurality of grooves and the second plurality of grooves being arranged in a random pattern in the wall of the distal tip.

Clause 20: The medical device of any one of clauses 16 to 19, further comprising one or more sensing elements disposed on the distal tip.

Clause 21: A medical device according to any one of clauses 16 to 20,

The fluid directing assembly is in fluid communication with an irrigation pump that delivers irrigation fluid to the fluid directing assembly; and in response to increasing the power of the at least one electrode to approximately 90 W, increasing an irrigation flow rate of the irrigation pump.

Clause 22: The medical device of any one of clauses 16 to 21, each aperture of the plurality of apertures being recessed a distance D from an outer surface of the distal tip.

Clause 23: The medical device of clause 22, wherein the distance D is between about 0.05 mm and about 0.2 mm.

Clause 24: The medical device of any of clauses 16 to 23, wherein a first portion of the plurality of apertures is oriented at a proximal angle relative to the longitudinal axis, the first portion being positioned in a row proximal to the proximal end of the distal tip.

Clause 25: The medical device of any of clauses 16 to 24, wherein a second portion of the plurality of apertures is oriented at a distal angle relative to the longitudinal axis, the second portion being positioned in a row proximal to the distal end of the distal tip.

Clause 26: The medical device of any of clauses 16 to 25, the aperture being configured to direct irrigation fluid to tissue within the body.

Clause 27: A method of directing an irrigation fluid from a medical probe, comprising: providing a probe having an elongated catheter body defining a longitudinal axis; a distal tip coupled to a distal end of the elongated catheter body, the distal tip having an outer surface, a cavity, a proximal end, a distal end, a wall, the wall having a plurality of orifices connecting the outer surface and the cavity, the orifices being arranged in a grid, the grid having columns generally parallel to the longitudinal axis and rows generally perpendicular to the longitudinal axis, the wall having a plurality of longitudinal grooves and a plurality of circumferential grooves, the distal tip including at least one electrode, the The at least one electrode is connected to an energy source to apply an ablation current to the tissue; and a fluid guiding assembly having an axial channel that is fluidly connected to the cavity of the distal tip and thereby fluidly connected to the plurality of orifices; providing an irrigation fluid into the axial channel of the fluid guiding assembly, guiding the irrigation fluid from the axial channel through one or more cross-axial channels perpendicular to the axial channel, through the cavity of the electrode and through the plurality of orifices into the tissue; and guiding the irrigation fluid from the plurality of orifices through the plurality of longitudinal grooves and the plurality of circumferential grooves.

Clause 28: The method of clause 27, wherein a first portion of the plurality of apertures is oriented at a proximal angle relative to the longitudinal axis, the first portion being positioned in a row proximal to the proximal end of the distal tip.

Clause 29: The method of clause 27 or 28, wherein a second portion of the plurality of apertures is oriented at a distal angle relative to the longitudinal axis, the second portion being positioned in a row proximal to the distal end of the distal tip.

Clause 30: The method of any one of clauses 27 to 29, each of the plurality of apertures being recessed a distance D from the outer surface of the distal tip.

Clause 31: The method of clause 30, wherein the distance D is between about 0.05 mm and about 0.2 mm.

Clause 32: The method according to clause 30 or 31 further includes: pressing the distal tip against the tissue until the wall of the distal tip is pressed against the tissue; and allowing the flushing fluid to flow through the multiple orifices without becoming blocked due to each of the multiple orifices being recessed from the outer surface of the distal tip.

Claims (20)

1. A medical device comprising: an elongated catheter body defining a longitudinal axis; a distal tip electrode coupled to a distal end of the elongated catheter body, the distal tip electrode having an outer surface, a lumen, a proximal end, a distal end, and a wall, the wall having a plurality of apertures connecting the outer surface and the lumen, the apertures being arranged in a grid having columns generally parallel to the longitudinal axis and rows generally perpendicular to the longitudinal axis; a plurality of longitudinal grooves formed in the wall of the distal tip electrode such that each longitudinal groove extends generally parallel to the longitudinal axis, each longitudinal groove of the plurality of longitudinal grooves having at least two of the plurality of orifices positioned within the respective longitudinal groove; and A first plurality of circumferential grooves are formed in the wall of the distal tip electrode such that each circumferential groove intersects at least one of the longitudinal grooves to define an orifice at such intersection. 2. The medical device according to claim 1 further comprises one or more sensing elements disposed on the distal end of the distal tip electrode, each of the one or more sensing elements being positioned between two adjacent longitudinal grooves. 3 . The medical device of claim 1 , each of the plurality of apertures being recessed a distance D from the outer surface of the distal tip electrode. 4. The medical device of claim 3, wherein the distance D is between about 0.05 mm and about 0.2 mm. 5. The medical device of claim 1, wherein a first portion of the plurality of apertures are oriented at a proximal angle relative to the longitudinal axis, the first portion being positioned in a row proximal to the proximal end of the distal tip electrode. 6. The medical device of claim 1, wherein a second portion of the plurality of apertures are oriented at a distal angle relative to the longitudinal axis, the second portion being positioned in a row proximate the distal end of the distal tip electrode. The medical device of claim 1 , wherein the aperture is configured to direct an irrigation fluid. 8. The medical device of claim 1, at least one circumferential groove of the first plurality of circumferential grooves having at least two apertures positioned in respective non-adjacent rows within the respective circumferential groove of the first plurality of circumferential grooves. 9. The medical device of claim 1, the plurality of longitudinal grooves having four apertures of the plurality of apertures positioned within the respective longitudinal grooves. 10. The medical device of claim 1, the plurality of longitudinal grooves and the first plurality of circumferential grooves forming a grid pattern on the wall of the distal tip electrode. 11. The medical device according to claim 1, further comprising: a fluid directing assembly having an axial passage in fluid communication with the lumen of the distal tip electrode and thereby in fluid communication with the plurality of orifices; and A blocking terminal is fixed in the cavity of the distal tip electrode, and the blocking terminal is configured to block the flow of fluid along the longitudinal axis, direct the flow of fluid through at least one cross-axial channel transverse to the axial channel, and direct the flow of fluid through the plurality of orifices. 12. The medical device according to claim 11, The distal tip electrode includes at least one electrode coupled to an energy source to apply an ablative current to tissue; The fluid directing assembly is in fluid communication with an irrigation pump that delivers irrigation fluid to the fluid directing assembly; and In response to increasing the power of the at least one electrode to approximately 90 W, increasing the irrigation flow rate of the irrigation pump. 13. A medical device comprising: an elongated catheter body defining a longitudinal axis; a distal tip coupled to a distal end of the elongated catheter body, the distal tip having an outer surface, a lumen, a proximal end, a distal end, and a wall, the wall including an end portion and a sidewall portion, the sidewall portion of the wall having a plurality of apertures connecting the outer surface and the lumen; The distal tip includes at least one electrode coupled to an energy source to apply an ablative current to tissue within a patient; a first plurality of grooves formed in the wall of the distal tip, each groove of the first plurality of grooves being formed in a first orientation relative to the longitudinal axis; a second plurality of grooves formed in the wall of the distal tip, the second plurality of grooves formed in a second orientation relative to the longitudinal axis; each of the first plurality of grooves and the second plurality of grooves having at least two respective apertures of the plurality of apertures positioned within the respective groove; a fluid directing assembly having an axial passage in fluid communication with the cavity of the distal tip and thereby in fluid communication with the plurality of orifices; and An occlusion terminal is fixed in the cavity of the distal tip, and the occlusion terminal is configured to occlude the flow of fluid along the longitudinal axis, guide the flow of fluid through at least one cross-axial channel transverse to the axial channel, and guide the flow of fluid through the plurality of orifices. 14. The medical device of claim 13, the first plurality of grooves and the second plurality of grooves each forming a diagonal groove in the wall of the distal tip relative to the longitudinal axis. 15. The medical device of claim 13, the first plurality of grooves and the second plurality of grooves arranged in a grid pattern of grooves in the wall of the distal tip. 16. The medical device of claim 13, the first plurality of grooves and the second plurality of grooves being arranged in a random pattern in the wall of the distal tip. 17. The medical device according to claim 13, The fluid directing assembly is in fluid communication with an irrigation pump that delivers irrigation fluid to the fluid directing assembly; and In response to increasing the power of the at least one electrode to approximately 90 W, increasing the irrigation flow rate of the irrigation pump. 18. The medical device of claim 13, wherein a first portion of the plurality of apertures are oriented at a proximal angle relative to the longitudinal axis, the first portion being positioned in a row proximal to the proximal end of the distal tip. 19. The medical device of claim 13, wherein a second portion of the plurality of apertures are oriented at a distal angle relative to the longitudinal axis, the second portion being positioned in a row proximate the distal end of the distal tip. 20. A method of directing an irrigation fluid from a medical probe, comprising: A probe is provided, the probe having an elongated catheter body defining a longitudinal axis; a distal tip connected to the distal end of the elongated catheter body, the distal tip having an outer surface, a cavity, a proximal end, a distal end, a wall, the wall having a plurality of orifices connecting the outer surface and the cavity, the orifices being arranged in a grid, the grid having columns generally parallel to the longitudinal axis and rows generally perpendicular to the longitudinal axis, the wall having a plurality of longitudinal grooves and a plurality of circumferential grooves, the distal tip including at least one electrode, the at least one electrode being connected to an energy source to apply an ablation current to tissue; and a fluid guiding assembly having an axial channel in fluid communication with the cavity of the distal tip and thereby in fluid communication with the plurality of orifices; providing a flushing fluid into an axial passage of the fluid directing assembly; directing the irrigation fluid from the axial channel through one or more trans-axial channels perpendicular to the axial channel, through the lumen of the electrode, and through the plurality of orifices into the tissue; and The irrigation fluid is directed from the plurality of apertures and through the plurality of longitudinal grooves and the plurality of circumferential grooves.