RU2829128C1 - Method for injection intra-arterial thrombolysis using ultrasonic navigation in acute ischemia of extremities - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention refers to medicine, namely to vascular surgery, and can be used for surgical treatment of thrombosis and embolism of arteries by thrombolysis. Under ultrasound control, preparation Actilyse is injected with an initial dose of 15 mg using 23 G needle. Injection is performed strictly through the thrombosed segment; the whole mass of the thrombus is infiltrated by reciprocating needle movements, followed by compression of the puncture zone with an ultrasonic sensor for 3-5 minutes. Further, the patient is heated with a blanket of the Equator system for 2 hours, setting the temperature mode to 44 °C. Then control ultrasonic scanning is performed in 2-4 hours. If thrombotic masses are preserved, the procedure is repeated.

EFFECT: method enables restoring the patency of arteries in thrombosis due to intrathrombotic introduction of tissue plasminogen inhibitor under control of ultrasonic navigation only.

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Description

The invention relates to medicine, namely to vascular surgery, and can be used in the surgical treatment of thrombosis and embolism of arteries using the thrombolysis method.

Arterial thrombosis and embolism of the extremities are one of the most serious and unresolved problems of vascular surgery. Currently, a number of revascularization strategies for arterial thrombosis and embolism have been proposed, each of which has its own advantages and disadvantages. However, an optimal treatment strategy that meets the criteria of speed, efficiency, safety and availability of the method has not yet been developed. Acute limb ischemia (ALI) is a sharp deterioration (incomplete ischemia), or absolute cessation (total, complete ischemia) of the main functions of regional blood flow: supplying tissues with oxygen, oxidation substrates and eliminating tissue metabolism products from tissues [1].

The main causes of AIC are thrombosis, embolism, trauma and vascular spasm. Among the causes of non-traumatic AIC, the most common is acute thrombosis of the artery in the area of the performed bypass or stenting, or progression of atherosclerosis in the aorta and vessels of the extremities, or embolism [2].

According to the 2020 European Society of Vascular Surgeons (ESVS) clinical guidelines for the treatment of acute lower limb ischemia, with mild Rutherford grade 2A ischemia, selective catheter thrombolysis (SCT) is recommended for the treatment of patients with ALI and a viable limb, along with open thrombectomy, while endovascular thromboaspiration methods can be used in addition to it [3].

To perform KTL, it is necessary to have special X-ray endovascular equipment, radiation safety, consumables, radiopaque agents, and specially trained personnel.

Intra-arterial thrombolysis began to be used for the treatment of thrombosis of arteries of the extremities in the 1980s [4].

In 2019, the largest systematic review and meta-analysis devoted to different protocols for performing this procedure, covering the period 1980-2010, was published. One hundred and six studies were included: 19 randomized controlled trials (RCTs), 38 prospective studies, 48 retrospective studies, and one mixed cohort study. The studies included a total of 10,643 cases, of which 9877 received KTL for lower extremity artery thrombosis. This work examines the effectiveness of various thrombolytics, their dosages, duration of therapy, immediate and long-term results, and complication rates, depending on different protocols for performing the procedure [5].

The technique basically involves puncturing the artery and implanting a 5-6 Fr arterial intradusser into it. Then, under X-ray control, with arterial contrast, a guidewire is inserted into the thrombosis zone through the entire thickness of the thrombus. A special irrigation catheter with lateral perforations along its entire length is inserted through the guidewire. A thrombolytic solution is injected through the catheter to dissolve the thrombus: urokinase, alteplase, streptokinase, prourokinase. The infusion continues until the thrombus is completely lysed and the artery is patency restored. According to this meta-analysis, the average duration of the procedure was 17.3-20.4 hours.

The closest to the claimed method is the method described by Falkowski A [6]. According to this method, an artery was punctured, through which radiocontrast angiography was performed, using a 6Fr introducer and a 5Fr catheter. A guidewire was passed through the thrombus under X-ray control, and a catheter with several side holes (Infusion set, Cook Medical, USA) was implanted along it. The distal end of the catheter was positioned in the most distal part of the thrombus. During the procedure, 2500 IU of heparin were usually administered. For thrombolysis, tissue plasminogen activator (rt-PA, Actilyse ^® ) was used, in a dilution of 0.2 mg / ml, 15 mg was administered as a bolus, at a rate of 1 mg / min for 15 minutes, and then 35 mg for 2 hours, as a constant infusion using an infusamate. During this time, the patient was administered heparin at a dose of 500 U/hour. After this, the adequacy of lysis was assessed by X-ray angiography. In case of incomplete thrombus lysis, another 10 mg was administered for another 2 hours.

The aim of the proposed invention is to perform selective intra-arterial thrombolysis using only ultrasound navigation, which allows for thrombus lysis and restoration of arterial patency without the use of X-ray visualization.

The essence of the invention consists in a set of essential features sufficient to achieve the desired technical result, and consists in restoring the patency of arteries in case of thrombosis by thrombolysis by intrathrombotic administration of tissue plasminogen inhibitor (t-PA, Actilyse®) under the control of ultrasound navigation only, which allows, by simplifying the procedure, to maintain clinical effectiveness similar to the standard method of catheter thrombolysis, without the use of X-ray visualization, without the use of radiocontrast agents, special consumables and X-ray surgical equipment, making it feasible in the conditions of any surgical hospital, reducing the likelihood of local hemorrhagic complications, complexity, and cost of manipulations.

In the period from October 2023 to January 2024, we operated on 23 patients with acute and chronic (post-thrombotic) arterial insufficiency at the Republican Clinical Hospital of the Ministry of Health of the Republic of Tatarstan and the Nizhnevartovsk District Clinical Hospital, and performed 24 injection thrombolysis procedures.

The majority of patients (13-61.9%) were men. The age ranged from 47 to 77 years (mean 64.6±1.7 years).

In 10 cases the etiology was acute thromboembolism, in the remaining 13 - thrombosis, including: - 4 femoropopliteal, 1 aortofemoral bypass graft and 1 superficial femoral artery stent. The lower limb was affected in 18 cases, the upper limb - in 4. The duration of the disease was up to 24 hours - 10 patients, 1-14 days - 9 patients, more than 14 days (maximum - 46 days) - 4 patients.

Acute ischemia (AIS) was present in 19 patients - 82.6%: grade 1 AIS - 7, grade 2A AIS - 10, grade 2B AIS - 2. Grade 3 chronic arterial insufficiency, with post-thrombotic occlusion history of more than 14 days, was present in 4 patients.

The initial dose of the drug was up to 15 mg (10-15 ml). In 11 cases, one procedure was enough to achieve the effect. If necessary, repeated injections were administered, usually at intervals of 4-5 hours. Two injections were required in 7 cases, three in 4 cases, and in one case, 4 injection thrombolysis procedures were administered. Thus, the average frequency of injections was 1.8±0.19.

The duration of thrombolysis ranged from 20 min to 48 hours (mean - 8.7±1.6 hours, median - 6 hours). The amount of drug used was 29.5±3.0 mg (15-65 mg). The average amount of drug per hour was 7.8±2.2 mg/hour (1.7-40.0).

As a result, the technical result could not be achieved only in 3 cases. All these patients had extensive thromboses of the femoropopliteal and popliteal-tibial segment. Nevertheless, in all three patients the clinical effect was still achieved - the degree of acute ischemia decreased to 0-1 degree (from 2A-B). Two of them additionally underwent catheter thrombolysis with a good technical and clinical effect. In another patient, with a post-thrombotic occlusion of 46 days, open thrombectomy was performed, and residual thrombi were removed from the popliteal and deep femoral artery.

Thus, the technical effect of injection thrombolysis in our group was 90.0%, the clinical effect was 95.7%.

No major hemorrhagic complications were recorded. In three cases (13.0%) there were local hematomas at the puncture sites that did not require revision. One patient died. The cause of death was polysegmental viral pneumonia, pulmonary edema, and acute cardiovascular failure. Postoperative mortality was 4.3%.

Within 30 days, the limb was preserved in all surviving patients, and there was no recurrence of symptoms. The overall clinical success, taking into account one deceased patient, was 95.7%.

Advantages of the method we have developed:

1. No need for X-ray surgical equipment, and therefore no need to ensure radiation safety;

2. No need for special consumables for X-ray endovascular surgery.

3. No need for radiocontrast agents, which is important for patients with kidney pathology and helps prevent contrast-induced nephropathy.

4. Puncture was performed with 21-23 G (0.64-0.82 mm) needles, whereas standard KTL requires the insertion of a 5-6 Fr (1.67-2.0 mm) intradusser into the artery. This potentially reduces the likelihood of local hemorrhagic complications.

5. Technical accessibility, which allows thrombolysis to be performed in any surgical department.

The essence of the method of injection intra-arterial thrombolysis in acute limb ischemia using ultrasound navigation includes artery puncture and intrathrombic injection of thrombolytic solution until arterial patency is restored. Puncture of thrombosed arteries is performed under ultrasound control, outside of calcified and significant atherosclerotic plaques, with a small-diameter 23 G (0.64 mm) needle. Injection of Actilyse® is performed strictly through the thrombosed segment, infiltrating the entire mass of the thrombus, dissolving the contents of a 50 mg vial in 50 ml of water for injection. An initial dose of 15 mg t-PA is used. The injection is performed at one or several points, depending on the extent of the thrombus. During the injection of the drug, reciprocating movements of the needle are performed, followed by compression of the puncture zone with a sensor for 3-5 minutes until complete hemostasis is achieved. The patient is monitored in a general surgical ward, with the patient warmed with an Equator blanket for 2 hours, setting the temperature to 44°C. Control ultrasound scanning is performed after 2-4 hours, depending on the observed clinical effect and reduction of acute ischemia. Upon achieving complete recanalization, restoration of blood flow, and relief of ischemia symptoms, the procedure is stopped.

If the clinical effect is insufficient, repeated injections of the drug are performed until the symptoms of acute ischemia are relieved and the main blood flow is restored.

When a connective tissue cuff or scars form around the thrombus, the puncture is performed using 21G (0.82 mm) needles.

Performing a puncture of thrombosed arteries under ultrasound control allows us to analyze the structure of the thrombus and the arterial wall.

Puncture of the artery outside of calcified and significant atherosclerotic plaques is performed to prevent dissection.

The use of a small diameter 23 G needle allows for arterial puncture and intrathrombotic injection of Actilyse® with minimal additional trauma.

Performing an injection of the drug strictly through the thrombosed segment, infiltrating the entire mass of the thrombus, followed by compression of the puncture zone by the sensor for 3-5 minutes, helps to avoid the formation of hematomas and hemorrhages.

The working solution is prepared by dissolving the contents of a 50 mg vial in 50 ml of water for injection, in accordance with the manufacturer's instructions.

The initial dose of the drug 15 mg t-PA was determined empirically.

Depending on the extent of the thrombus, the injection is performed at one or several points, ensuring infiltration of the entire thrombotic mass with the drug.

Reciprocating movements of the needle during the injection of the drug are performed in order to stratify the structure of the thrombus and distribute it evenly.

Subsequent compression of the puncture area by the sensor for 3-5 minutes ensures complete hemostasis.

The patient is monitored in a general surgical ward, with the patient warmed with an Equator blanket for 2 hours, setting the temperature to 44°C, since there is literature data on the increased effectiveness of thrombolysis with an increase in body temperature [7]. Our observations confirmed a positive correlation between an increase in body temperature and fractional loss of clot mass.

Control ultrasound scanning is performed after 2-4 hours, depending on the observed clinical effect and reduction of acute ischemia symptoms. In case of complete recanalization, restoration of blood flow, and relief of ischemia symptoms, the procedure is stopped.

If the clinical effect is insufficient, repeated injections of the drug are performed until the symptoms of acute ischemia are relieved and the main blood flow is restored.

When a connective tissue cuff or scars form around the thrombus, the puncture is performed using 21G needles, which have a larger diameter and strength.

The method is explained by the illustrations provided.

Fig. 1 - Fig. 5 illustrate clinical example 1, where:

Fig. 1 - photo of the upper limb upon admission;

Fig. 2 shows the result of ultrasound scanning: thrombotic masses in the lumen of the artery;

Fig. 3 - intra-arterial injection of the drug under ultrasound navigation;

Fig. 4 - ultrasound scanning: puncture needle in the lumen of the artery;

Fig. 5 - ultrasound scanning: restoration of main blood flow in the brachial artery;

Fig. 6 shows the view of the hand after completion of injection thrombolysis.

The method is carried out as follows.

The patient is positioned supine. Punctures are usually performed without anesthesia or with preliminary intramuscular administration of analgesics, since the injections are relatively painless. Puncture of thrombosed arteries is performed under ultrasound control, outside of calcified and significant atherosclerotic plaques, with a small-diameter 23G (0.64 mm) needle, the injection of Actilyse® is performed strictly through the thrombosed segment, infiltrating the entire mass of the thrombus, dissolving the contents of a 50 mg vial in 50 ml of water for injection. The initial dose of the drug is 15 mg t-PA. The injection is performed at one or several points, depending on the length of the thrombus, performing reciprocating movements with the needle, followed by compression of the puncture zone with the sensor for 3-5 minutes, until complete hemostasis is achieved. The patient is monitored in the general surgical ward, with the patient warmed with an Equator blanket for 2 hours, setting the temperature to 44°C. Control ultrasound scanning is performed after 2-4 hours, depending on the observed clinical effect and reduction of acute ischemia. In the event of complete recanalization, restoration of blood flow, and relief of ischemia symptoms, the procedure is stopped.

If the clinical effect is insufficient, repeated injections of the drug are performed until the symptoms of acute ischemia are relieved and the main blood flow is restored.

When a connective tissue cuff or scars form around the thrombus, the puncture is performed using 21 G (0.82 mm) needles.

Clinical example 1

Patient K., 71 years old, was admitted with the diagnosis: Acute occlusion (thromboembolism) of the brachial artery on the right. OI stage 2A on the right according to Zatevakhin.

Objectively: the general condition is satisfactory. Hemodynamics are stable, BP is 140 and 90 mm Hg. HR is 87 per minute, arrhythmia. Breathing is conducted in all fields, no wheezing. RR is 19 per minute. The abdomen is soft, painless. Diuresis is preserved. Locally: the right s/c is moderately cool to the touch in the area of the hand and lower third of the forearm, pale in color, superficial sensitivity is reduced, deep sensitivity is preserved, active and passive movements are preserved, pulsation in the arteries of the limb is not determined, (Fig. 1).

During ultrasound scanning of the arteries of the right upper limb: the subclavian and axillary arteries are patent, the blood flow is main, the brachial artery is patent to the middle third of the arm, in the lumen of the brachial artery from the middle third and distally, to its bifurcation, thrombotic masses of varying echogenicity are located. During scanning in the color duplex scanning mode, the blood flow in the projection of the brachial, radial, ulnar arteries was not determined, data for atherosclerotic lesion of the arterial bed were not obtained, the occlusion was assessed as thromboembolic. (Fig. 2)

According to ECG data - paroxysm of atrial fibrillation, examined by a cardiologist, prescribed antiarrhythmic drugs. Given the presence of acute arterial occlusion in the patient, heparin 5000 IU was administered subcutaneously in the admission department.

Due to the presence of acute limb ischemia stage 2A according to Zatevakhin in the patient of the clinic, according to emergency indications, the council of doctors decided to perform injection intra-arterial thrombolysis with tissue plasminogen activator t-PA (Actilyse). The method of administration of the drug is an intrathrombal bolus injection, under ultrasound control. No contraindications, absolute or relative, to the thrombolysis procedure were identified. The patient was offered the intervention, written consent for the procedure was obtained.

In the dressing room of the surgical department, under aseptic conditions, under ultrasound visualization with a portable ultrasound system GE Logiq E with a linear sensor, a 23G puncture needle 150 mm long, a puncture of the thrombosed segment of the brachial artery was performed at 3 points, one after the other (Fig. 3). The drug injections were performed without anesthesia, with a preliminary intramuscular administration of Tramadol 2.0 ml. With each puncture, the thrombolytic Actilyse was administered intrathrombally as a bolus, with reciprocating movements of the needle during administration in order to stratify the thrombus structure and distribute it evenly, until complete infiltration of the thrombus along its entire length (Fig. 4). After each puncture and removal of the needle, moderate compression of the artery puncture site was performed with an ultrasound sensor, the duration of compression until hemostasis was achieved was, on average, 3-5 minutes. The total time of the injection thrombolysis procedure was 15 minutes, the total dose of the administered thrombolytic was 15 mg. Then the patient was transported to the general surgical ward, where she was warmed by the Equator patient heating system (blanket), with a set temperature of 44°C, for 2 hours.

After 2 hours, the patient noted clinical improvement, manifested in a decrease in the intensity of the pain syndrome and warming of the limb. During control ultrasound scanning after 4 hours, complete recanalization of the lumen of the brachial, radial and ulnar arteries was noted, with restoration of the main blood flow (Fig. 5). Clinically, the patient noted complete regression of the symptoms of acute ischemia, with relief of the pain syndrome, and restoration of sensitivity. The hand is physiologically colored, warm (Fig. 6).

In the postoperative period, the patient received LMWH in a therapeutic dose, followed by a transfer to DOAC (rivaroxaban) in a dose of 20 mg, with a recommendation for lifelong use. The patient was discharged on the 4th day, under the supervision of a cardiologist.

Clinical example 2

Patient L., 77 years old, was admitted urgently with the diagnosis: Atherosclerosis. Acute occlusion (thromboembolism) of the common arterial artery, the hemiarterial artery, and the left atrial artery. OI stage 2A on the left according to Zatevakhin.

Objectively: the general condition is satisfactory. Hemodynamics are stable, BP 120/70 mm Hg. HR 81 per min, rhythm is regular. Breathing is in all fields, no wheezing. RR 17 per min. The abdomen is soft, painless. Diuresis is preserved. Locally: the left lower limb is moderately cool to the touch in the area of the foot and shin, pale in color, superficial sensitivity is reduced, deep sensitivity is preserved, active and passive movements are preserved, pulsation on the left is absent at all levels.

During ultrasound scanning of the left lower limb, the common, deep and superficial femoral arteries were visualized, blood flow was not determined in the color Doppler mode, pulsating hyperechoic thrombotic masses were found in the lumen of the common femoral artery, blood flow in the deep and superficial femoral arteries was not localized. During contrast imaging study (MSCT angiography): occlusion of the left common, deep and superficial femoral arteries with restoration of blood flow at the level of 1 segment of the popliteal artery, moderate diffuse atherosclerotic lesion of the arteries of the lower limb and the aortoiliac segment without significant damage. An ECG was performed in the emergency department, the rhythm was irregular, atrial fibrillation. The patient was examined by a cardiologist, antiarrhythmic drugs were prescribed.

Considering the presence of acute occlusion (thromboembolism) of the left femoral artery in the patient and the presence of acute ischemia, heparin 5000 IU was administered subcutaneously in the emergency department.

Due to the presence of acute limb ischemia stage 2A on the left according to Zatevakhin in the patient of the clinic, according to emergency indications, the council of doctors decided to perform local endovascular transarterial thrombolysis of the peripheral artery with tissue plasminogen activator t-PA (Actilyse). The method of administration of the drug is intrathrombic bolus injection, under echo-control. Contraindications (absolute and relative) to the thrombolysis procedure were not identified. The patient was offered the intervention, written consent for the procedure was obtained.

In the dressing room of the surgical department, under aseptic conditions, under ultrasound visualization with a portable ultrasound system GE Logiq E with a linear sensor, a 23G puncture needle 150 mm long, a puncture of the left common femoral artery (CFA) was performed at one point, the superficial femoral artery (SFA) at 2 points, a total of 15 mg of tissue plasminogen activator Actilyse was administered as a bolus. When administering the drug, reciprocating movements of the needle were made in order to stratify the thrombus structure and distribute it evenly (for thrombus infiltration along the entire length). After the injection and removal of the needle, moderate compression of the artery puncture site was performed with an ultrasound sensor, the duration of compression was on average 3-5 minutes until complete hemostasis was achieved. The total time of the injection thrombolysis procedure was 15 minutes. The patient was then transported to the general surgical ward, where the patient was warmed using the Equator patient heating system (blanket) with a set temperature of 44 C for 2 hours.

After 3 hours, the patient noted clinical improvement, manifested in a decrease in the intensity of the pain syndrome, warming of the limb. During the control ultrasound scan after 4 hours, complete recanalization of the lumen of the left OBA, GBA was noted. Starting from the middle third of the SBA, thrombotic masses persist, occluding the artery to the level of the popliteal artery. It was decided to perform additional administration of thrombolytic.

Under ultrasound control, an additional dose of 15 mg of Actilyse was administered from two points into the SFA at the level of the middle-lower third using the above-described method. Control ultrasound examination after 2 hours - restoration of the main blood flow in the SFA along the entire length of the artery. The total dose of Actilyse was 30 mg, the total duration of the procedure was 6 hours 30 minutes.

When scanning the arteries of the left lower limb, no hemodynamically significant damage to the arterial bed was detected, there is no data for distal embolism. There are no indications for angiographic examination. Clinically, the patient noted complete regression of symptoms of acute ischemia with relief of pain syndrome and complete restoration of sensitivity. Locally: in the left inguinal region and in the middle third of the thigh, small diameter ecchymosis, no data for hematoma.

In the postoperative period, the patient received LMWH in a therapeutic dose, aspirin 100 mg, with a transfer to DOAC (rivaroxaban 20 mg) constantly for life. Discharged on the 4th day under the supervision of a cardiologist at the clinic.

Sources of information:

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Claims (2)

1. A method of injection intra-arterial thrombolysis in acute limb ischemia, consisting in the fact that under ultrasound control, an injection of Actilyse with an initial dose of 15 mg is performed using a 23 G needle, while the injection is performed strictly through the thrombosed segment, the entire mass of the thrombus is infiltrated, performing reciprocating movements with the needle, followed by compression of the puncture zone with an ultrasound sensor for 3-5 minutes, after which the patient is warmed with an Equator system blanket for 2 hours, setting the temperature regime to 44 ° C, a control ultrasound scan is performed after 2-4 hours, if the thrombotic masses are preserved, the procedure is repeated. 2. The method according to item 1, characterized in that when a connective tissue cuff or scars form around the thrombus, the puncture is performed using 21G needles.