Ultrasound guided percutaneous thrombin injection for the treatment of iatrogenic pseudoaneurysms

Percutaneous balloon-assisted ultrasound-guided direct thrombin embolization of superficial femoral artery pseudoaneurysm: a case series and literature review

BACKGROUND

Superficial femoral artery (SFA) pseudoaneurysms, a rare but potentially life-threatening complication, that can arise after vascular interventions or trauma. This case series explores the efficacy and safety of a minimally invasive treatment modality, percutaneous ultrasound-guided thrombin injection (PUGTI) combined with balloon occlusion, in three patients with SFA pseudoaneurysms.

CASE PRESENTATION

Three patients (age: 71-82 years; 3 female) with SFA pseudoaneurysms underwent PUGTI with balloon occlusion. The procedure involved direct thrombin injection under ultrasound guidance while occluding the parent artery using a balloon catheter. Follow-up was conducted at 1 week and 1 month post-procedure to assess technical success, complications, and recurrence.

CONCLUSION

PUGTI combined with balloon occlusion appears to be a safe and effective treatment for SFA pseudoaneurysms, particularly for larger pseudoaneurysms. The procedure is associated with a high technical success rate. Balloon occlusion may offer a safer alternative to direct thrombin injection without occlusion, as it potentially minimizes the risk of complications such as distal thromboembolism.

Percutaneous Transaxillary Impella Device Placement Resulting in Iatrogenic Subclavian Artery Pseudoaneurysm

Subclavian artery pseudoaneurysm (PSA) is a rare complication arising from transaxillary Impella device placement during high-risk percutaneous coronary intervention (PCI). Despite the increasing prevalence of Impella use, literature addressing this complication is scarce. This case emphasizes the limited existing evidence on subclavian artery PSA and highlights the importance of recognizing it as a potential risk. With high-risk PCI and Impella use gaining popularity, understanding this complication is crucial for early detection and appropriate management. A 62-year-old male with a past medical history of type II diabetes mellitus, peripheral artery disease, hypertension, and chronic tobacco use presents with recurrent episodes of exertional chest pain and dyspnea. Initial workup with an electrocardiogram showed ST-segment elevations in the anteroseptal leads. The patient underwent right- and left-sided cardiac catheterization, which revealed severe stenosis of the left anterior descending artery and findings of cardiogenic shock. The patient required mechanical circulatory support with a percutaneous left ventricular assist device during the procedure; this was placed via transaxillary approach due to the patient having peripheral artery disease in bilateral femoral arteries. The patient had a complicated clinical course, but the patient's clinical picture slowly improved, and the percutaneous left ventricular assist device was removed. Roughly six weeks after the removal of the device, the patient developed a large fluid collection in the chest wall anterior to the left shoulder. Imaging revealed a ruptured left distal subclavian artery PSA. The patient was promptly taken to the catheterization laboratory and a covered stent was deployed over the site of the PSA. Repeat angiography revealed brisk flow through the left subclavian artery into the axillary artery with no extravasation into the chest wall.

Endovascular repair of a pseudoaneurysm of the popliteal artery following arthroscopic knee surgery: case report and review of literature

We report a case of a pseudoaneurysm of the popliteal artery following arthroscopic knee surgery. Endovascular repair was successfully used as the treatment for this patient and studies have shown this to be a safe alternative to surgery.

Anastomotic pseudoaneurysm formation after bypass grafting to porcelainized peroneal artery: successful treatment by percutaneous thrombin injection

We present a rare case of a distal anastomotic pseudoaneurysm after bypass grafting to a porcelainized peroneal artery. Successful management was achieved by percutaneous thrombin injection. This case illustrates the value of nonsurgical intervention for this rare but difficult problem.

Endovascular treatment of iatrogenic axillary artery pseudoaneurysm under echographic control: a case report

Aim

Brief case report of the treatment of a large axillary artery pseudoaneurysm after a pacemaker using a left brachial cutdown and a retrograde delivery of a covered stent using ultrasound and fluoroscopic guidance. The patient's renal function precluded the use of contrast materials.

Case Report

A 77 years old man presenting with acute renal failure and haemoglobin decrease arrived with an expanding pseudoaneurysm of the left axillary artery from a pacemaker placement. Considering the site of the lesion and patient's comorbidities, under echographic control, a Hemobahn^® stent-graft was placed; fluoroscopy assisted manipulation of guidewires and sheaths into the aortic arch. The procedure was successfully ended without any complications. At 8 months the stent graft was still patent.

Conclusion

Ultrasound guidance may represent an alternative for pseudo-aneurysm exclusion without any use of contrast medium, especially in those patient where lesions are easily detectable using ultrasonography and when comorbidities contraindicate aggressive surgical or angiographic approach.

Personal experiences in direct ultrasound-guided injection of thrombin into the lumen of pseudoaneurysm as a method of treatment in case of iatrogenic femoral artery damage

BACKGROUND

Pseudoaneurysms constitute a quite common complication of procedures requiring puncture of the common femoral artery. The risk factors of the condition include: obesity, arterial hypertension, sex (more prevalent in males) as well as antithrombotic therapy.

MATERIAL/METHODS

The US-guided injection of thrombin into the pseudoaneurysm lumen was performed in patients referred from the Department of Invasive Cardiology who had undergone coronarography or coronary angioplasty. Pseudoaneurysms constituted the complication of common femoral artery canulation. After setting the diagnosis of pseudoaneurysm by means of Doppler ultrasound, patients with large pseudoaneurysms of volume exceeding 10 mm were qualified for thrombin injection. Generally, 33 patients underwent the treatment. In 3 cases - due to the presence of multiocular pseudoaneurysm - thrombin was administered twice.

RESULTS

Taking into account the safety of the procedure, ultimately 33 patients were qualified for thrombin administration, in whom aneurism of diameter exceeding 10 mm was diagnosed. In 3 patients with aneurysm of less than 10mm, only a compression band was used prophylactically. In one case, because of a considerable oedema surrounding the tissue, as well as deep location of the aneurysm in the groin, thrombin treatment was not given due to technical reasons. In 30 cases, single administration of thrombin was effective and resulted in a complete thrombosis of the pseudoaneurism lumen within a couple of seconds following thrombin injection. In 3 patients with multicellular aneurysm, thrombin was given twice, resulting in a total obliteration of the pseudoaneurysm in two cases only. No complications were observed after the performed procedures. No recanalisation of pseudoaneurysms was demonstrated in follow-up examinations.

CONCLUSIONS

1. Direct thrombin injection into the pseudoaneurysm lumen can constitute an alternative method of treatment for open surgical techniques. 2. The procedure is highly effective, cheap and minimally invasive.

Thrombosis of popliteal artery pseudoaneurysm by deployment of angioplasty balloon after total knee arthroplasty

Vascular complications after total knee arthroplasty are rare, with incidence ranging between 0.03% and 0.2%. We describe a case of a popliteal artery false aneurysm after total knee arthroplasty successfully treated by deployment of an angioplasty balloon across the aneurysm neck resulting in thrombosis.

Pseudoaneurysms Occurring as a Result of Fractures Giving Rise to the Appearance of Pseudotumors: A Short Series

Pseudoaneurysms are focal enlargements of the vascular lumen due to partial or complete disruption of the arterial wall. These are an uncommon complication of fractures. The presence of a pseudoaneurysm adjacent to a fracture fragment can cause a pressure effect. This pressure not only impairs fracture healing but sometimes can erode the adjacent bone, producing the appearance of a pseudotumor. We present two such cases and discuss the management of these patients.

Endovascular treatment of arterial injury as an uncommon complication after orthopedic surgery

PURPOSE

To evaluate selective and superselective catheter therapy of serious arterial damage associated with orthopedic surgery of the pelvis, hip joint, femur, and knee.

MATERIALS AND METHODS

Between 1989 and 2005, 16 consecutive patients with arterial damage after orthopedic surgery (seven women, nine men; mean age, 62 years; age range, 21-82 y) underwent angiographic exploration. Seven patients were in hemodynamically unstable condition. Initial orthopedic procedures were iliac crest internal fixation (n = 1); total hip prosthesis (n = 3); revision of total hip prosthesis (n = 4); revision of acetabular cup prosthesis (n = 1); gamma-nailing, nail-plate fixation, or intramedullary nailing (n = 3); and total knee prosthesis (n = 4).

RESULTS

Angiography showed pseudoaneurysms (n = 11), vascular lacerations with active extravasation (n = 3), and arteriovenous fistulas with extravasation (n = 2). After angiographic documentation of serious arterial injury, 14 patients were treated with a single or coaxial catheter technique in combination with coils alone, coils and polyvinyl alcohol particles, coils and Gelfoam pledgets, or Gelfoam pledgets; or balloon occlusion with isobutyl cyanoacrylate and coils. Two patients were treated with covered stents. In all, bleeding was effectively controlled in a single session in 16 patients, with immediate circulatory stabilization. Major complications included death, pulmonary embolism, and postprocedural hematoma.

CONCLUSION

Selective and superselective catheter therapy may be used for effective, minimally invasive management of rare but potentially life-threatening vascular complications after orthopedic surgery.

Postcatheterization pseudoaneurysm: results of US-guided percutaneous thrombin injection in 240 patients

PURPOSE

To prospectively evaluate ultrasonographically (US) guided percutaneous thrombin injection for treatment of femoral artery and brachial artery pseudoaneurysms.

MATERIALS AND METHODS

The university institutional review board approved the study. Informed consent was obtained from all patients. Two hundred forty patients with postcatheterization femoral artery (n = 132) or brachial artery (n = 8) pseudoaneurysms were treated with US-guided bovine thrombin (1.000 IU/mL) injection. At diagnosis, 107 (44.6%) patients received anticoagulation therapy; 159 (66.2%), antiplatelet therapy; and 76 (31.7%), both therapies. Pseudoaneurysm size, length and width of pseudoaneurysm neck, thrombin dose, therapy outcome, and complications were documented. The peak blood flow in peripheral arteries was determined before and after thrombin injection. Follow-up duplex US was performed 12-24 hours, 5-7 days, and 21-25 days after treatment. A nonpaired t test was used to compare differences in age between the male and female patients. Two-way analysis of covariance was performed to analyze the influences of factors that may have been related to the amount of thrombin used.

RESULTS

Mean pseudoaneurysm volume was 4.69 cm3 +/- 5.49 (standard deviation). Simple and complex pseudoaneurysms were treated in 165 and 75 patients, respectively. A total of 260 thrombin injections were performed: 1.04 injections per patient with a simple pseudoaneurysm and 1.17 injections per patient with a complex pseudoaneurysm. The mean injected thrombin dose was 425.31 IU +/- 341.75 for all pseudoaneurysms, 382.12 IU +/- 281.00 for simple pseudoaneurysms only, and 520.33 IU +/- 434.64 for complex pseudoaneurysms only. There was only a computational correlation between pseudoaneurysm size and thrombin dose (r2 = 0.07). The primary success rate was 93.8% overall, 95.8% for simple pseudoaneurysms, and 89% for complex pseudoaneurysms. The secondary success rate was 99.6% overall, 100% for simple pseudoaneurysms, and 99% for complex pseudoaneurysms. Early (at < or =24 hours) reperfusion occurred in one simple and five complex pseudoaneurysms. Four late reperfusions-two in simple and two in complex pseudoaneurysms-were detected at 1-week follow-up; no late reperfusions were detected at 3 weeks. Thromboembolic complications occurred in two patients and resolved spontaneously. One mild allergic reaction and no infections occurred.

CONCLUSION

US-guided percutaneous thrombin injection enables successful, safe management of postcatheterization pseudoaneurysms.

Percutaneous thrombin injection for the treatment of a post-pancreatitis pseudoaneurysm

Visceral artery pseudoaneurysms are often treated surgically or by transcatheter embolisation. We report a case of a pseudoaneurysm in a patient with chronic pancreatitis, which was successfully occluded by percutaneous injection of thrombin into the pseudoaneurysmal sac as a first-line management.

Current treatment methods for postcatheterization pseudoaneurysms

Pseudoaneurysms are a recognized complication of arterial catheterization. Until recently, the standard method of treatment has been surgical. The past decade has seen the introduction of several minimally invasive techniques that have largely replaced surgical treatment of pseudoaneurysms. The most commonly used methods are ultrasound-guided compression and percutaneous injection of thrombin into the pseudoaneurysm. This review article describes all the methods available for the treatment of postcatheterization pseudoaneurysms, presents results from the largest published series, and discusses the relative merits of each technique.

Case report: insertion of a covered stent for treatment of a popliteal artery pseudoaneurysm following total knee arthroplasty

We report the use of a covered stent to successfully treat a pseudoaneurysm of the popliteal artery, which occurred following total knee arthroplasty. Percutaneous endovascular repair offers a safe alternative to surgical management of this condition.

Femoral pseudoaneurysms: management with percutaneous thrombin injections--success rates and effects on systemic coagulation

PURPOSE

To determine the success rate of percutaneous ultrasonographically (US) guided thrombin injection in the treatment of femoral pseudoaneurysms and to evaluate the effects of thrombin injection on systemic coagulation parameters.

MATERIALS AND METHODS

Fifty femoral pseudoaneurysms (37 simple pseudoaneurysms with one lobe and 13 complex pseudoaneurysms with two or three lobes) were treated with US-guided percutaneous thrombin injections. Pseudoaneurysm size, neck length and width, thrombin dose, outcome of therapy, and complications were documented prospectively. Duplex sonographic follow-up examinations were performed at 12-24 hours and 5-7 and 21-25 days. In 25 patients, activated thromboplastin time, Quick test (prothrombin time), thrombin time, fibrinogen, D-dimer, antithrombin III, thrombin-antithrombin III complex, and prothrombin fragments 1 and 2 were determined before and at 2, 5, and 10 minutes after thrombin injection. Differences in results before and those after thrombin injection were evaluated by means of the one-sample t test.

RESULTS

Mean volume of pseudoaneurysms was 5.84 cm(3) +/- 4.89 (SD). Fifty-eight thrombin injections were performed. Mean thrombin dose was 357 IU +/- 291 in simple and 638 IU +/- 549 in complex pseudoaneurysms. Primary success rate was 36 of 37 (97%) for simple and eight of 13 (61%) for complex pseudoaneurysms. Reperfusion occurred in four complex pseudoaneurysms (none in simple ones). Secondary success rate was 100%. No thromboembolic, infectious, or allergic complications occurred. During follow-up, reperfusion was detected in one patient with a complex pseudoaneurysm. Levels of thrombin-antithrombin III complex increased significantly (P <.05) after thrombin injection, whereas changes in all other laboratory tests were not significant.

CONCLUSION

US-guided percutaneous injection of thrombin is successful and safe in the management of femoral pseudoaneurysms. The increase of thrombin-antithrombin III complex indicates the possibility of thrombin passage into the arterial circulation.

Percutaneous management of access site complications

Percutaneous cardiac catheterization and endovascular procedures are associated with complications at the vascular access site. While surgery has been the traditional treatment for vascular access complications, the current state of the art permits percutaneous management of many access site complications. Surgical repair may be required only when percutaneous methods fail, are not available, or are unsuitable.

Lumbar artery pseudoaneurysm following renal biopsy: treatment with ultrasound-guided thrombin injection

latrogenic pseudoaneurysms are usually seen following arterial catheterization. However, we describe a case of a 23-year-old woman who developed a pseudoaneurysm of a lumbar artery following renal biopsy. In view of her progressing renal failure, arterial embolization was felt to be inappropriate, and although the pseudoaneurysm could be seen ultrasonically, guided compression could not be applied because of the location of the aneurysm deep to the lumbar musculature. Hence, the pseudoaneurysm was thrombosed by percutaneous ultrasound-guided injection of thrombin directly into the pseudoaneurysm sac. This resulted in immediate thrombosis of the aneurysm and no recurrence on follow-up imaging. Thrombin injection for femoral artery pseudoaneurysms following catheterization is becoming more widely accepted, and our case demonstrates that this technique might be applied to pseudoaneurysms elsewhere in the body.

Percutaneous thrombin injection of carotid artery pseudoaneurysm

PURPOSE

To report the successful treatment of a carotid artery pseudoaneurysm by percutaneous thrombin injection.

CASE REPORT

A 71-year-old man with end-stage renal failure presented with acute left ventricular failure. The right common carotid artery (CCA) was punctured during attempted jugular line insertion, and he developed a large pseudoaneurysm connected to the CCA by a long, narrow neck. Ultrasound-guided compression was unsuccessful, so another technique was attempted. An occlusion balloon was inflated in the CCA at the neck of the aneurysm to avoid distal embolization, and 250 units of human thrombin were injected into the sac percutaneously; thrombosis was instantaneous. There were no procedural complications, and repeat ultrasound at 3 months showed resolution of the hematoma and no residual pseudoaneurysm. There were no neurological complications.

CONCLUSIONS

Percutaneous thrombin injection may be a new and successful method of treating carotid artery pseudoaneurysms.

Therapeutic thrombin injection of pseudoaneurysms: a multicenter experience

The standard non-invasive treatment of pseudoaneurysms has been ultrasound-guided compression (UGC). Problems with UGC include pain at the site of compression, long compression times and incomplete closure. Each of these difficulties is exacerbated with large pseudoaneurysms. Recently, ultrasound-guided injection of pseudoaneurysms with thrombin has gained popularity. The goal of this study was to report a multicenter registry using this technique and in so doing detail the clinical utility and safety of this emerging procedure. The medical records of all patients diagnosed with pseudoaneurysm in the vascular laboratory who underwent thrombin injection over the past year were reviewed for patient characteristics and clinical outcome. There were 91 patients (55 male) with a mean age of 69 years. Three patients also had an arteriovenous fistula. The majority of patients were receiving one or more antiplatelet agents and/or anticoagulants. All patients underwent pseudoaneurysm injection with bovine thrombin. The mean aneurysm diameter was 3.3 cm, with a range of 1.5-6.3 cm. Successful thrombosis of the pseudoaneurysm was achieved in 89/91 (98%) of cases. Anticoagulation with heparin was used in one of the unsuccessful cases. In two cases, UGC was used to close a small active region that did not completely thrombose after thrombin injection. There were two patients who had recurrence of pseudoaneurysm the day after successful injection and thrombosis of the pseudoaneurysm. There were no local complications after injection; however, one patient suffered a pulmonary embolus that was thought to be unrelated to the procedure. In conclusion, thrombin injection for the treatment of pseudoaneurysms is safe and effective, even in patients receiving anticoagulation. This procedure should be considered as the initial therapeutic approach for peripheral pseudoaneurysms.

Sonographically guided thrombin injection of iatrogenic femoral pseudoaneurysms: further experience of a single institution

OBJECTIVE

In September 1998, we began to treat iatrogenic femoral pseudoaneurysms with direct thrombin injection under sonographic guidance. Our purpose was to determine the success and complication rate of this technique.

SUBJECTS AND METHODS

We treated 114 consecutive patients who had iatrogenic femoral pseudoaneurysms using direct thrombin injection. A 22-gauge spinal needle was placed into the pseudoaneurysm lumen with sonographic guidance, and bovine or human thrombin (mean dose, 306 U; range, 50--1600 U) was injected under continuous color Doppler sonographic visualization. Distal pulses were monitored. Patient demographics, clinical variables, and pseudoaneurysm characteristics were collected.

RESULTS

One hundred three (90%) of 114 patients had pseudoaneurysm thrombosis after the first procedure. Of the remaining 11 patients who required a second procedure 1 day later, thrombosis occurred in seven (64%) of 11. Thus, the overall success rate was 96% (110/114). Of the patients who required one injection, the mean thrombosis time was 12 sec (range, 3--90 sec). Three (3%) of 114 patients required conscious sedation. Of the patients with successful thrombosis, 24-hr follow-up sonograms showed no recurrent pseudoaneurysm. Four patients (4%) had potential complications: a "blue toe" 15 hr after the thrombin injection that resolved spontaneously, a groin abscess, leg ischemia that resolved spontaneously after 4 hr, and crampy buttock pain that resolved spontaneously.

CONCLUSION

For the treatment of iatrogenic femoral pseudoaneurysms, thrombin injection under sonographic guidance is a quick and effective method of therapy. Failures and complications are infrequent. At our institution, sonographically guided thrombin injection has replaced compression repair.

Percutaneous treatment of pseudoaneurysms using fibrin adhesive

This study was performed to assess the safety and efficacy of treatment of iatrogenic pseudoaneurysms with fibrin adhesive. 28 patients with iatrogenic pseudoaneurysms were treated. The first 20 patients had either at least one previously unsuccessful treatment of ultrasound guided compression repair (UGCR), a contraindication to UGCR or could not tolerate the procedure. Diagnosis was confirmed on ultrasound and angiography and a balloon inflated across the neck of the pseudoaneurysm. Fibrin adhesive was injected under ultrasound control directly into the pseudoaneurysm sac. The balloon was deflated after 15 min and check ultrasound and angiography performed, with a further ultrasound at 24 h. The subsequent eight patients underwent embolisation as the first line treatment without use of a protective balloon. 16 of the first 20 patients (80%) and all of the subsequent 8 patients had successful embolisation of the pseudoaneurysm after a single treatment. Two pseudoaneurysms failed to thrombose despite two treatments in one case and three treatments in the other, and both required surgery. The only significant complication was the development of local cellulitis in one patient. In conclusion, embolisation of iatrogenic aneurysms with fibrin adhesive is a safe and effective treatment. It should be considered as an alternative to surgery and UGCR.

Treatment of femoral artery pseudoaneurysm with percutaneous thrombin injection

Pseudoaneurysm formation of the femoral artery is a well-known complication following catheter-based vascular procedures. Ultrasound-guided compression or surgical correction are commonly used for its repair. We describe a new method of treatment for femoral pseudoaneurysm. The pseudoaneurysm is visualized by contralateral angiography and thrombosed with a percutaneous thrombin injection while the distal vessel is isolated with a brief balloon inflation. Fluoroscopically guided percutaneous thrombin injection is a promising, minimally invasive technique for the treatment of iatrogenic pseudoaneurysm, especially in patients with compromised distal circulation.

Femoral artery thrombosis after percutaneous thrombin injection of an external iliac artery pseudoaneurysm

Ultrasound-guided percutaneous thrombin injection has been developed as a less invasive and highly successful treatment of iatrogenic femoral pseudoaneurysms. Most of these lesions have been the result of catheterization procedures. This method has proved to be highly effective, and few complications have been reported. Specifically, native arterial thrombosis, although recognized as a severe complication, has been mentioned only briefly in the literature. We present a case of the successful management of native arterial thrombosis after attempted percutaneous thrombin injection of a chronic external iliac artery pseudoaneurysm. This case serves to illustrate the risk factors for this complication and the treatment options once it occurs. The success of this treatment with acute iatrogenic femoral pseudoaneurysms may not necessarily translate into similar success in other anatomic locations and clinical situations.

Femoral pseudoaneurysm thrombinjection

BACKGROUND

The risk of pseudoaneurysm (PSA) increases with the number of catheterizations performed for cardiovascular diagnosis and therapy. Thrombin injection, or "thrombinjection," is an alternative to ultrasound-guided compression or surgical repair. Thrombinjection is effective and economical, but the specter of systemic arterial thrombosis hinders its wide application. We report cautionary steps taken prior to injection and lessons learned during our first 20 cases.

METHODS AND RESULTS

Thrombinjection was performed under ultrasound (US) guidance in 12 women and 8 men with PSA after femoral catheterization. PSA varied in size from 17 to 39 mm with neck openings from 1.5 to 3.9 mm. Under local anesthesia and US longitudinal view, a 20-gauge US needle tip was placed in the PSA away from the neck. With 12 cases under 600 units, 100 to 2,300 units of thrombin (1,000 U/mL) were injected slowly. Slow injection, positioning of the ball of thrombus formed at the needle tip, probe compression, and combined or interchangeable use of US color flow and B-mode were the essential techniques utilized. All PSA thrombosed successfully on the first treatment. One patient had fever and another returned for compression treatment of a second, not recurrent, PSA.

CONCLUSIONS

Successful thrombinjection was accomplished by focusing on common femoral artery PSA with small neck openings, avoiding arteriovenous fistulas, and using standard thrombin concentration, US needle, state of the art ultrasonography, slow injection, thrombus ball positioning, and adjunctive probe compression.

Ultrasound guided percutaneous thrombin injection of iatrogenic femoral artery pseudoaneurysms after coronary angiography and intervention

Ultrasound guided percutaneous thrombin injection has recently been described for the treatment of iatrogenic femoral pseudoaneurysms. Patient selection and technical aspects of this technique are still evolving and safety data, particularly after coronary intervention, remains limited. The percutaneous thrombin injection of femoral artery pseudoaneurysms in 13 consecutive patients, most of whom were receiving antiplatelet/anticoagulant treatment (aspirin 11, heparin 4, clopidogrel 6), is reported. Thrombin (1000 U/ml) was injected over several seconds until Doppler colour flow within the cavity ceased. The median dose of thrombin injected was 800 U (range 200-1000 U) and the treatment was successful in all cases without complication. In one case, thrombus was visualised within the arterial lumen immediately after thrombin injection, but this dissolved spontaneously within five minutes without evidence of embolisation. In contrast to ultrasound guided compression, percutaneous thrombin injection of femoral pseudoaneurysms is a rapid, well tolerated, and successful technique even in patients receiving antiplatelet/anticoagulant treatment.