Comparison of pharmacological thrombolysis with mechanical thrombectomy in thrombosed arteriovenous fistulas and grafts: a systemic review and meta-analysis

AIM

To compare the effectiveness and safety of pharmacological thrombolysis and mechanical thrombectomy.

MATERIAL AND METHODS

This review was conducted in accordance with the PRISMA guidelines. Pooled proportions and subgroup analysis were calculated for primary and secondary patency rates, technical success, clinical success, major and minor complications rates.

RESULTS

This systematic review identified a total of 6,492 studies of which 17 studies were included for analysis. A total of 1,089 patients comprising 451 (41.4 %) and 638 (58.6 %) patients who underwent thrombolysis and mechanical thrombectomy procedures, respectively, were analysed. No significant differences were observed between thrombolysis and mechanical thrombectomy procedures in terms of technical success, clinical success, major and minor complications rates, primary and secondary patency rates; however, subgroup analysis of overall arteriovenous fistulas (AVFs) and arteriovenous grafts (AVGs) demonstrated a significantly higher rate of major complications within the AVF group (p=0.0248).

CONCLUSION

The present meta-analysis suggests that pharmacological thrombolysis and mechanical thrombectomy procedures are similarly effective and safe; however, AVFs are subject to higher major complications compared to AVGs.

Rotational thrombectomy versus balloon maceration in dialysis access salvage

BACKGROUND

Although end stage renal disease patients who undergo hemodialysis frequently experience dialysis-associated thrombotic complications, there remains a paucity of literature comparing the efficacy of different endovascular salvage techniques for grafts and fistulas. This study aims to compare primary patency in dialysis access following salvage mechanical thrombolysis/thrombectomy with a rotational thrombolysis device versus balloon maceration.

METHODS

Using a database of patient records at a tertiary medical center, all patients who underwent rotational thrombectomy with the Cleaner XT™ Rotational Thrombectomy System for endovascular salvage of arteriovenous fistula or arteriovenous graft from August 2016 to July 2022 were included in the population. Fourteen patients who underwent balloon maceration for endovascular salvage were matched to the patients in the rotational thrombectomy group based on date of procedure. The primary patency of the fistula or graft for the two groups was measured.

RESULTS

A total of 13 patients who underwent dialysis access salvage with rotational thrombectomy (10 grafts, 3 fistulas) were matched with 14 patients who underwent balloon maceration for dialysis access salvage (10 grafts, 4 fistulas). Six patients in both groups required additional graft access salvage (46% rotational thrombectomy; 43% balloon maceration). The median time to next dialysis salvage was 51 days for rotational thrombectomy and 43.5 days for balloon maceration (W + 9, critical value 1; compatible with statistically significant difference).

CONCLUSION

Endovascular access salvage by rotational thrombectomy may provide longer primary patency compared to salvage by balloon maceration. However, a longer follow-up prospective study of a larger study population is necessary to clarify the safety and efficacy of rotational thrombectomy using the Cleaner XT™ device.

Initial experience of thrombectomy using vascular snare with multiple loops for chronic organized thrombi in patients with thrombosed native hemodialysis fistulas

BACKGROUND

Thrombi in native hemodialysis access frequently exhibit chronic organized feature because they have formed over a long period. Removal of these is quite difficult owing to relatively large volume, resilient feature, limitations of the introducer sheath size, etc. In this study, we report our experience using a vascular snare for the removal of these thrombi in native arteriovenous fistula (AVF).

MATERIALS AND METHODS

The medical records of patients who underwent recanalization for thrombosed AVFs from January 2019 to August 2023 were reviewed. During the study period, a total of 29 native fistulas (19 brachiocephalic, nine radiocephalic, and one radiobasilic) in 25 patients were treated using a vascular snare with multiple loops (19 men and six women). Characteristics of the AVFs, endovascular procedures, technical and clinical results, and complications were evaluated.

RESULTS

Anatomic and clinical success rates were 96.6% and 100%, respectively. Total thrombosis was observed in 21 (72.4%) fistulas. Aneurysmal changes were found in 22 (75.9%) fistulas. The mean fistula age at the time of the procedure was 60.9 months (standard deviation, 52.2). Thrombectomy was initiated using a vascular snare in 14 fistulas. In 15 fistulas for which the procedures were initiated using a rotational percutaneous thrombectomy device (PTD), a vascular snare was subsequently used because recanalization failed or was insufficient due to chronic organizing thrombi. Additional aspiration and balloon angioplasty were performed in 27 (93.1%) and 28 (96.6%), respectively. Pharmacological thrombolysis was performed in one fistula for long segmental thrombosis combined with arterial thrombosis. The mean procedure time, excluding thrombolysis, was 91.9 min (standard deviation, 55.5). No complications related to the use of the vascular snare was observed.

CONCLUSION

The use of a vascular snare with multiple loops was safe and highly effective for the removal of chronic organized thrombi in the recanalization of thrombosed AVFs.

Pulmonary embolism in an ESRD patient following minimal venotomy and milking for salvage of dysfunctional autogenous arteriovenous fistula

Pulmonary embolism can be a complication following an attempted salvage of a dysfuctional arteriovenous fistula (AVF). We report a case of bilateral pulmonary embolism in a patient with underlying pericardial effusion who, following minimal venotomy and milking of the AVF, developed sudden and significant respiratory distress, and later improved.

Bare-Metal Stent in Dysfunctional Hemodialysis Access: An Assessment of Circuit Patency according to Access Type and Stent Location

Purpose

To evaluate the circuit patency after nitinol bare-metal stent (BMS) placement according to the type of access and location of the stent in dysfunctional hemodialysis access.

Materials and Methods

Between January 2017 and December 2019, 159 patients (mean age, 64.1 ± 13.2 years) underwent nitinol BMS placement for dysfunctional access. The location of stents was as follows: 18 brachiocephalic vein, 51 cephalic arch, 40 upper arm vein, 10 juxta-anastomotic vein, 7 arteriovenous (AV) anastomosis, and 33 graft-vein (GV) anastomosis. Circuit patency was evaluated by the Kaplan-Meier method, and cox regression model.

Results

A total of 159 stents were successfully deployed in 103 AV fistula (AVF) and 56 AV graft (AVG). AVG showed lower primary and secondary patency at 12-months compared with AVF (primary patency; 25.0% vs. 44.7%; p = 0.005, secondary patency; 76.8% vs. 92.2%; p = 0.014). Cox regression model demonstrated poorer primary patency at 12 months after stenting in the cephalic arch and GV anastomosis compared with the other sites.

Conclusion

AVF showed better primary and secondary circuit patency at 12 months following the placement of BMS compared with AVG. Stents in the cephalic arch and GV anastomosis were associated with poorer primary patency at 12 months compared to those in other locations.

Characterization of hemodialysis fistulas experienced abrupt thrombosis and determination of a proper follow-up protocol: A retrospective cohort study and an interventionist's perspective

Abrupt thrombosis is a form of thrombosis that occurs unexpectedly and without being preceded by hemodialysis fistula (AVF) dysfunction during dialysis. We found that AVFs with a history of abrupt thrombosis (abtAVF) appeared to have more episodes of thrombosis and required more frequent interventions than those without such history. Therefore, we sought to characterize the abtAVFs and examined our follow-up protocols to determine which one is optimal. We performed a retrospective cohort study using routinely collected data. The thrombosis rate, AVF loss rate, thrombosis-free primary patency, and secondary patency were calculated. Additionally, the restenosis rates of the AVFs under the follow-up protocol/sub-protocols and the abtAVFs were determined. The thrombosis rate, procedure rate, AVF loss rate, thrombosis-free primary patency, and secondary patency of the abtAVFs were 0.237/pt-yr, 2.702/pt-yr, 0.027/pt-yr, 78.3%, and 96.0%, respectively. The restenosis rate for AVFs in the abtAVF group and the angiographic follow-up sub-protocol were similar. However, the abtAVF group had a significantly higher thrombosis rate and AVF loss rate than AVFs without a history of abrupt thrombosis (n-abtAVF). The lowest thrombosis rate was observed for n-abtAVFs, followed up periodically under the outpatient or angiographic sub-protocols. AVFs with a history of abrupt thrombosis had a high restenosis rate, and periodic angiographic follow-up with a mean interval of 3 months was presumed appropriate. For selected populations, such as salvage-challenging AVFs, periodic outpatient or angiographic follow-up was mandatory to extend their usable lives for hemodialysis.

Results of the endovascular treatment system for occluded native arteriovenous fistula

BACKGROUND

Arteriovenous fistula is the definitive vascular access for patients on long-term haemodialysis. The aim of this study is to present the techniques and results of the Endovascular Treatment System that we have developed for managing the occluded native arteriovenous fistula.

METHODS

The current study is a retrospective chart review on all patients who presented with an occluded native arteriovenous fistula and underwent attempted recanalization between 1 January 2005 and 31 December 2014.

RESULTS

A total of 130 patients were included in the study. Post-intervention primary access patency was 83.8% at 6 months, 78.7% at 12 months, 64.6% at 2 years and 59.6% at 3 years. Post-intervention assisted access patency in fistulas-in-use was 86.5% at 6 months, 81% at 12 months, 66.8% at 2 years and 61.2% at 3 years. Post-intervention secondary patency for all cases was 84.7% at 6 months, 80.2% at 12 months, 66.1% at 2 years and 62% at 3 years. Post-intervention secondary patency in fistula-in-use was 91.1% at 6 months, 90% at 12 months, 85% at 2 years and 74.6% at 3 years. Access survival nor patency differed significantly when incisional thrombectomy was compared to angioplasty with or without stenting with access survival of 91.2% and 92.5% at 12 months and access patency of 82.9% and 89.7% at 12 months (P = 0.834 and P = 0.898, respectively).

CONCLUSIONS

In autologous arteriovenous thrombosed fistulae, the use of endovascular techniques to revive the access is a viable and safe technique to employ in most cases.

Safety and Efficacy of the Percutaneous Manual Aspiration Thrombectomy Technique to Treat Thrombotic Occlusion of Native Arteriovenous Fistulas for Hemodialysis

목적

대상과 방법

결과

결론

Thrombosed native hemodialysis fistulas: Technical and clinical outcomes of endovascular recanalization and factors influencing patency

Purpose:

To evaluate the technical and clinical results of endovascular recanalization of thrombosed native hemodialysis fistula and the factors influencing patency.

Methods:

A retrospective study was conducted with 73 patients who had thrombosed arteriovenous fistulas and were treated with endovascular methods. Patient characteristics, arteriovenous fistula-related characteristics, and endovascular procedures were analyzed. Technical and clinical results and patency rates were evaluated. The factors influencing patency were analyzed using a univariate and multivariate Cox proportional hazards model.

Results:

Technical and clinical success rates were 93% (68/73) and 85% (62/73), respectively. At 3, 6, and 12 months, the primary patency rates were 87.9%, 73.3%, and 64.8%; assisted primary patency rates were 89.2%, 78.6%, and 70.7%; and secondary patency rates were 90.8%, 87.2%, and 83.1%, respectively. Previous intervention and cephalic arch stenosis were risk factors for lower primary and assisted primary patency ( p < 0.05 for all). Cephalic arch stenosis was the only risk factor for lower secondary patency ( p < 0.05). No major complications associated with the procedures were noticed.

Conclusion:

Endovascular treatment was effective for the immediate recanalization of thrombosed arteriovenous fistula. In addition, previous intervention and cephalic arch stenosis were significantly related to lower arteriovenous fistula patency.

The feasibility of surgical salvage of thrombosed arteriovenous fistula by an interventional nephrologist

Background

Salvage of a thrombosed arteriovenous fistula (AVF) by secondary fistula conversion may be more effective than a conventional endovascular procedure for forearm fistula thrombosis. Surgical access procedures are an undeveloped area in interventional nephrology compared to endovascular procedures. Herein, the author report the results of surgical salvage of thrombosed AVFs by interventional nephrologists.

Methods

The author retrospectively analyzed 52 surgical salvage procedures for AVF thrombosis (radiocephalic fistula = 44 cases, brachiocephalic fistula = 8 cases) that were performed by interventional nephrologist between March 2007 and January 2016.

Results

Secondary fistula formation using the proximal vein was performed for 46 cases (88.5%); outflow rerouting was performed for two cephalic-arch stenosis cases (3.9%), simple thrombectomy was performed for two cases (3.9%), and a graft interposition was performed for two cases (3.9%). Technical success after the surgical procedures was achieved in 51 cases (98.1%), and 39 AVFs (75.0%) were prepared for immediate puncturing without catheter insertion. The primary and secondary patency rates for AVF at 6, 12, 18, and 24 months were 88.5%, 83.2%, 83.2%, and 83.2% and 96.0%, 96.0%, 93.2%, and 93.2%, respectively. The re-intervention rate was 0.27 ± 0.92/patient/ year.

Conclusion

Based on these results, the author conclude that surgical salvage of a thrombosed AVF, when performed under local anesthesia by a skilled interventional nephrologist, offers favorable short- and long-term success and should be the preferred treatment.

Endovascular recanalization of a thrombosed native arteriovenous fistula complicated with an aneurysm: technical aspects and outcomes

OBJECTIVE

To evaluate the technical aspects and outcomes of endovascular recanalization of a thrombosed native arteriovenous fistula (AVF) complicated with an aneurysm.

MATERIALS AND METHODS

Sixteen patients who had a thrombosed AVF complicated with an aneurysm (two radiocephalic and 14 brachiocephalic) were included in this study. Recanalization procedures were performed by mechanical thrombectomy using the Arrow-Trerotola percutaneous thrombectomy device and adjunctive treatments. We evaluated dose of thrombolytic agent, underlying stenosis, procedure time, technical and clinical success, and complications. The primary and secondary patency rates were calculated using the Kaplan-Meier analysis.

RESULTS

The thrombolytic agents used were 100000 U urokinase mixed with 500 IU heparin (n = 10) or a double dose of the mixture (n = 6). The thrombi in aneurysms were removed in all but two patients with non-flow limiting residual thrombi. One recanalization failure occurred due to a device failure. Aspiration thrombectomy was performed in 87.5% of cases (n = 14). Underlying stenoses were found in the outflow draining vein (n = 16), arteriovenous anastomosis or juxtaanastomosis area (n = 5), and the central vein (n = 3). Balloon angioplasty was performed for all stenoses in 15 patients. Two patients with a symptomatic central vein stenosis underwent insertion of a stent after balloon angioplasty. Mean procedure time was 116.3 minutes. Minor extravasation (n = 1) was resolved by manual compression. Both technical and clinical success rates were 93.8% (n = 15). The primary patency rates at 3, 6, and 12 months were 70.5%, 54.8%, and 31.3%, respectively. The secondary patency rates at 3, 6, and 12 months were 70.5%, 70.5%, and 47.0%, respectively.

CONCLUSION

Thrombosed AVF complicated with an aneurysm can be successfully recanalized, and secondary patency can be prolonged with endovascular treatment.

Recanalization of thrombosed arteriovenous fistulas for hemodialysis by minimal venotomy

The present work describes the preliminary results of a new method of minimally invasive thrombectomy in the treatment of thrombosed arteriovenous fistula (AVF) with dilated aneurysm. Data from 25 patients who were treated with this minimal venotomy technique were retrospectively reviewed. The minimal venotomy was made on the dilated fistula, and thrombectomy was performed with forceps and Fogarty catheters through the venotomy site. Technical and clinical success was achieved in all 25 patients. There were two major and two minor complications (8% each). The two major complications consisted of bleeding at the venotomy site after early suture removal.