Pharmacomechanical thrombolysis for the treatment of thrombosed native arteriovenous fistula: a single-center experience

Direct Percutaneous Thrombolysis (DPT): A novel method of salvaging Thrombosed Native Arteriovenous Fistula

INTRODUCTION

Thrombosed arteriovenous fistulas (AVFs) are either treated by thrombectomy or pharmaco-mechanical thrombolysis with or without percutaneous balloon angioplasty. In this study, we have described an effective and economical technique of salvaging these fistulae using a 20-22-gauge spinal needle and urokinase and have named it direct percutaneous thrombolysis (DPT).

MATERIALS AND METHOD

This prospective study comprised of 148 patients out of which 120 patients presented with AVF thrombosis and were divided into two groups; those with no obvious stenosis on ultrasound (n = 38) and second with venous stenosis (n = 82). Remaining 28 patients developed thrombosis post angioplasty for venous stenosis. Percutaneous injection of urokinase into the thrombus was done under ultrasound guidance, followed by balloon angioplasty if there was associated stenosis.

RESULTS

In 38 patients who didn't have any stenosis, 32 AVFs were successfully thrombolysed by DPT, with technical success of 84.2%. Remaining six patients required angioplasty because of chronic nature of clot. In 82 patients who had venous stenosis, 80 cases were treated successfully by DPT followed by angioplasty with technical success of 97.5%. In third group (n = 28), who developed thrombosis post angioplasty, 100% success rate was noted. The mean length of thrombus was 31.4 ± 4.6 mm and mean diameter of thrombosed vein was 10.5 ± 1.2 mm. There were no major complications encountered during the procedure. Minor complications were seen in 19 patients which included prolonged oozing from puncture site and local hematoma formation.

CONCLUSION

Ultrasound guided DPT with urokinase is a safe and economical option for salvaging thrombosed AVF without vascular stenosis that does not need angioplasty.

Patency of Drug-Coated versus Conventional Balloon Angioplasty for Hemodialysis Access Stenosis

Purpose

This study aimed to evaluate the post-intervention target primary patency of drug-coated balloon angioplasty (DCBA) compared with conventional balloon angioplasty (CBA) in the treatment of the dysfunctional autogenous arteriovenous fistula (AVF) in a real-world clinical setting.

Materials and Methods

This retrospective study included 24 patients with end-stage renal disease, who developed dysfunctional AVF during hemodialysis, and underwent endovascular treatment using CBA and DCBA from January 1, 2014, to June 30, 2021. The demographic data of patients and details regarding their fistula were recorded. Post-intervention target primary patency was analyzed.

Results

Sixteen men and 8 women with an average age of 63.9 ± 14.2 years, who underwent 333 endovascular treatments in 57 target lesions of access were enrolled. DCBA was a protective factor for the treatment of a target lesion of dysfunctional access with an adjusted hazard ratio of 0.725 (95% confidence interval [CI]: 0.528-0.996; P = 0.047). According to the Weibull proportional hazards regression model, DCBA showed a longer post-intervention target primary patency than CBA.

Conclusion

DCBA has better outcomes in terms of post-intervention target primary patency in the real-world treatment of dysfunctional autogenous AVF.

The related factors to the re-thrombosis of hemodialysis arteriovenous graft after endovascular salvage

BACKGROUND

Only a few issues of the related factors to hemodialysis access dysfunction have been evaluated, and the effects of antiplatelets to improve the patency of hemodialysis access remained controversial. Hence, this study aimed to determine the related factors to the re-thrombosis of arteriovenous grafts (AVGs) after endovascular treatment.

METHODS

This retrospective study was conducted at a university-affiliated teaching hospital in Southern Thailand. All patients who underwent hemodialysis with thrombosed AVG, who had pharmacomechanical thrombolysis from January 2016 to December 2018, were enrolled. Post-intervention primary patency was analyzed by the Kaplan-Meier method, and the related factors to the re-thrombosis of AVG were evaluated using logistic regression.

RESULTS

A total of 157 patients with thrombosed hemodialysis AVG were enrolled. The most common graft location and configuration was a forearm loop graft (65%). Post-intervention primary patency rate at 1, 3, and 6 months were 79.0%, 67.1%, and 54.0%, respectively. Diabetes mellitus (DM) was a significant related factor for re-thrombosis (hazard ratio [HR], 1.89; 95% confidence interval [CI], 1.20-2.98; p = 0.006). A single antiplatelet after the procedure was a protective factor for re-thrombosis (HR, 0.58; 95% CI, 0.38-0.89; p = 0.013). The median post-intervention primary patency was 15.7 months in the group of single antiplatelet usage, which was better than that of the non-antiplatelet group (p = 0.012).

CONCLUSION

DM and antiplatelet usage were significant related factors to the re-thrombosis of hemodialysis AVG after endovascular salvage.

Results of drug-eluting stent in significant restenosis of the hemodialysis access: An initial study

BACKGROUND

This study aimed to report the 12-month results of drug-eluting stent (DES) for the treatment of significant restenosis of the hemodialysis access.

MATERIALS AND METHODS

A total of 14 patients (seven men and seven women; median age 70 years; range of 50-83 years) with significant restenosis of hemodialysis accesses were enrolled from January 2017 to December 2018. A total of 10 arteriovenous graft (AVG) and four arteriovenous fistulae were treated with DES. Study outcomes included primary patency of the target lesion and circuit.

RESULTS

Venous anastomosis of the AVG was the most common target lesion for DES insertion (nine hemodialysis accesses). The range of follow-up time was 12-36 months. Primary patency rates of target lesion before DES (patency for last conventional balloon angioplasty [CBA]) versus target lesion after DES at 6 and 12 months were 29% versus 100% and 7% versus 86% (p < 0.001). Primary patency rates of pre-DES circuit (patency for last CBA) versus post-DES circuit at 6 and 12 months were 29% versus 64% and 7% versus 29%, respectively (p = 0.058).

CONCLUSION

DES might improve the patency rate of target lesion in patients with significant restenosis of the hemodialysis access.

Outcomes of Catheter-Directed Thrombolysis for Arteriovenous Fistula Thrombosis in Singapore: Is It Still Relevant Today?

Objective: To review the outcomes of catheter-directed thrombolysis (CDT) for salvage of thrombosed arteriovenous fistula (AVF) in a single centre in Southeast Asia.

Methods: A retrospective study of CDT in AVF between January 2015 and July 2018 at a tertiary university hospital was carried out.

Results: Within the study period, 85 patients underwent CDT for AVF thrombosis. Of these patients, 78% underwent CDT for 24 h and 12% required CDT for 48 h. Moreover, 14% of patients had bleeding during CDT and hence required a decrease in dosing or complete cessation. Incidence of intracranial haemorrhage was 1%, and technical success was 92%. Post CDT, primary patency rates at 12, 24 and 36 months were 87%, 62% and 36%, respectively; assisted primary patency rates at 12, 24 and 36 months were 96%, 82% and 69%, respectively; and secondary patency rates at 12, 24 and 36 months were 99%, 93% and 86%, respectively. Multivariate analysis did not identify any predictive factors for patency post CDT.

Conclusion: Within our study population, CDT for AVF salvage conferred good technical results with low rates of complications. There was good primary patency at 12 months, and the results were sustained up to 36 months. It remains a useful modality for fistula salvage, avoiding surgical intervention.

Vacuum-assisted mechanical thrombectomy in extensively occlusive thrombosis of dialysis arteriovenous grafts with indigo system

PURPOSE

To present a selected series of extensively occlusive thrombosis of arteriovenous graft treated with the Penumbra's Indigo System.

MATERIALS AND METHODS

Ten patients with acute (within 72 h) extensively occlusive thrombosis of arteriovenous graft (mean extension = 30.1 (range = 15-45) cm) were treated at our institution with the Indigo System. Of the 10 cases, thrombosis was extended to venous outflow in 7 cases and to both arterial inflow and venous outflow in 3 cases.

RESULTS

Both anatomic and clinical success were achieved in 8 of the 10 procedures (80.0%). In the 2 cases of technical failure, the patients underwent surgical thrombectomy with the finding of arteriovenous graft exhaustion, which was then replaced. The 6-month primary patency, primary-assisted patency, and secondary patency rates were 37.5% (3/8), 50.0% (4/8), and 62.5% (5/8). We reported 2 complications (one minor and one major adverse event).

CONCLUSION

Percutaneous mechanical thrombectomy aspiration with Indigo System is a relatively safe and effective procedure and can be used even in extensively thrombosed arteriovenous graft.

Transcatheter Thrombolysis with Percutaneous Transluminal Angioplasty Using a Trans-Brachial Approach to Treat Thrombosed Arteriovenous Fistulas

Background

Arteriovenous fistulas (AVFs) are used to provide vascular access for hemodialysis in patients with end-stage renal failure. However, stenosis and thrombosis can compromise long-term AVF patency. The objective of this study was to evaluate catheter thrombolysis with percutaneous transluminal angioplasty (PTA), using a trans-brachial approach, for acutely thrombosed AVFs.

Material/Methods

This retrospective study examined 30 cases of AVF thrombosis treated between January 1, 2015 and January 1, 2017. All patients received transcatheter thrombolysis with PTA using a trans-brachial approach. AVF patency was assessed after 6 months.

Results

Thrombolysis with PTA was performed at 2 to 72 h after diagnosis of AVF occlusion due to acute thrombosis, and AVF patency was restored in all patients. After 6 months, the primary and secondary patency rates were 76.7% and 93.3%, respectively. For type I stenosis, primary patency was achieved in 10 of 16 patients (62.5%) and secondary patency was achieved in 14 of 16 patients (87.5%). For type II stenosis, primary patency was achieved in 13 of 14 patients (92.9%) and secondary patency was achieved in 14 of 14 patients (100%). Comparing type I and II stenosis, a significant difference was detected in the rates of primary patency (odds ratio=0.909, 95% confidence interval 0.754–1.096, P=0.049), but not secondary patency (P=0.178), after 6 months.

Conclusions

Our study provides preliminary evidence that catheter-directed thrombolysis with PTA using a trans-brachial approach can achieve high patency rates when used to treat acutely thrombosed AVFs.

Salvage of thrombosed arteriovenous fistulae of patients on hemodialysis: report on the experience of a Brazilian center

INTRODUCTION

Hemodialysis vascular access thrombosis is an acute event that can interrupt the dialytic treatment. A timely management can restore access patency, avoiding the use of central venous catheters and their complications.

OBJECTIVE

To present the experience from a Brazilian Interventional Nephrology Center (INC) in the salvage of arteriovenous fistula (AVF) and grafts for hemodialysis.

METHODS

A retrospective study was performed to evaluate the primary and secondary patencies of 41 hemodialysis accesses with thrombosis confirmed by ultrasound and submitted to endovascular salvage procedures. We considered clinical success the use of the access for at least 3 subsequent hemodialysis sessions. The procedures were done in an outpatient center by interventional nephrologists. Patients were followed for up to 18 months with Doppler every 3 months.

RESULTS

Forty-five salvage procedures were performed in 41 accesses of 40 hemodialysis patients with native AVF or grafts. Of these, 90% were AVF, mostly upper arm, and 10% were grafts. Clinical success rate was 60% (27 procedures). Primary patency at 12 months was 39% and secondary was 52%. Gender of the patient, diabetes, and location of the access did not correlate statistically with outcomes. There were 3 major complications (anastomosis rupture, grade 3 hematoma, and anaphylactic shock).

CONCLUSION

The majority of thrombosed accesses can be successfully treated, maintaining its long-term patency. The need of repeated intervention is frequent.

Spanish Clinical Guidelines on Vascular Access for Haemodialysis

Vascular access for haemodialysis is key in renal patients both due to its associated morbidity and mortality and due to its impact on quality of life. The process, from the creation and maintenance of vascular access to the treatment of its complications, represents a challenge when it comes to decision-making, due to the complexity of the existing disease and the diversity of the specialities involved. With a view to finding a common approach, the Spanish Multidisciplinary Group on Vascular Access (GEMAV), which includes experts from the five scientific societies involved (nephrology [S.E.N.], vascular surgery [SEACV], vascular and interventional radiology [SERAM-SERVEI], infectious diseases [SEIMC] and nephrology nursing [SEDEN]), along with the methodological support of the Cochrane Center, has updated the Guidelines on Vascular Access for Haemodialysis, published in 2005. These guidelines maintain a similar structure, in that they review the evidence without compromising the educational aspects. However, on one hand, they provide an update to methodology development following the guidelines of the GRADE system in order to translate this systematic review of evidence into recommendations that facilitate decision-making in routine clinical practice, and, on the other hand, the guidelines establish quality indicators which make it possible to monitor the quality of healthcare.

Paclitaxel-Coated Balloon Angioplasty for Early Restenosis of Central Veins in Hemodialysis Patients: A Single Center Initial Experience

Objective

To report the results of angioplasty with paclitaxel-coated balloons for the treatment of early restenosis of central veins in hemodialysis patients.

Materials and Methods

Sixteen patients (9 men and 7 women; mean age 65.8 ± 14.4 years; range, 40-82 years) with 16 episodes of early restenoses of central veins within 3 months (median patency duration 2.5 months) were enrolled from January 2014 to June 2015. Ten native central veins and 6 intra-stent central veins were treated with double paclitaxel-coated balloons (diameter 6-7 mm) plus a high pressure balloon (diameter 12-14 mm). The study outcomes included procedural success (< 30% residual stenosis) and primary patency of the treated lesion (< 50% angiographic stenosis without re-intervention).

Results

Procedural success was achieved in all 16 cases of central vein stenoses. The mean diameter of the central vein was 3.7 ± 2.4 mm before the procedure vs. 11.4 ± 1.8 mm after the initial procedure. There were no procedure-related complications. The mean diameters of the central veins at 6 months and 12 months were 7.8 ± 1.3 mm and 6.9 ± 2.7 mm, respectively. The primary patency rates at 6 months and 12 months were 93.8% and 31.2%, respectively. One patient had significant restenosis of the central vein at 3 months. The median primary patency period was 9 months for paclitaxel-coated balloons and 2.5 months for the last previous procedure with conventional balloons (p < 0.001).

Conclusion

In our limited study, paclitaxel-coated balloons seem to improve the patency rate in cases of early restenosis of central veins. However, a further randomized control trial is necessary.