Lysis-Assisted Balloon (LAB) Thrombectomy. A Declotting Technique for the Treatment of Thrombosed Arteriovenous Dialysis Grafts. 5-Year Experience of 241 Endovascular Procedures

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.

Management of Thrombosed Dialysis Access Circuits

Thrombotic occlusion of autologous arteriovenous fistulas or synthetic arteriovenous grafts is a serious adverse event in hemodialysis patients and declotting should be performed before next hemodialysis session, in order to avoid a central venous catheter. Various techniques exist to declot a thrombosed vascular access, including open surgical thrombectomy, catheter-directed thrombolysis and use of different types of percutaneous thrombo-aspiration catheters and mechanical thrombectomy devices. These devices can be categorized as devices with direct wall contact and hydrodynamic devices without direct wall contact. Technical and early clinical outcome results of percutaneous hemodialysis declotting are high and ranging between 70 and 100%; late clinical patency results are much lower related to restenosis or re-thrombosis; these patency results are higher for autologous arteriovenous fistulas compared to synthetic arteriovenous grafts and mainly depend on the combined efficacy of successful thrombectomy and durable treatment of the underlying stenoses, associated with the acute thrombosis.

Chameleon™ PTA balloon catheter: A single device in managing thrombosed AV access

Thrombectomy is a common procedure for maintenance of arteriovenous (AV) access and is critical to prolong access life. Techniques for performing thrombectomy are incredibly diverse, ranging from open surgical procedures to percutaneous interventions. Percutaneous interventions include a combination of thrombectomy devices to clear the thrombus and balloon angioplasty to treat the underlying lesion. In this case report we describe a novel technique using a single device, the Chameleon™ PTA balloon catheter (Medtronic, Minneapolis, MN) balloon catheter, to safely and efficiently perform a percutaneous intervention.

Endovascular salvage of thrombosed haemodialysis vascular access

Background: Haemodialysis access thrombosis is associated with significant morbidity and access abandonment rates, for which endovascular salvage is a well described treatment option. This study aimed to evaluate the outcomes of endovascular salvage procedures of thrombosed vascular access circuits and identify factors influencing outcomes. Patients and methods: Retrospective review of 328 consecutive procedures performed over 10 years at our institution between January 2010 and December 2019. Patient demographics, access circuit characteristics, procedure details and outcome data were collected. Kaplan-Meier survival curves were used to estimate patency rates and Cox multivariate regression analysis to identify factors affecting outcomes. Results: Technical and clinical success rates were 87.8% and 75.9% respectively. The primary, primary assisted and secondary patency rates at 6 months were 42.2%, 46.7% and 59.1%; and at 12 months were 23.4%, 28.3% and 41.8% respectively. Median access circuit survival was 9.2 months. Major complication rate was 5.2% including 3 procedure-related deaths. Native AVF, lower time from thrombosis to intervention and pharmacomechanical thrombectomy using AngioJet^TM predicted positive outcomes. Previous thrombectomy within 3 months and residual thrombus at completion were associated with poorer outcomes. Age and hypertension predicted higher complication rates. Conclusions: This is one of the largest single center series of endovascular salvage of thrombosed haemodialysis access and demonstrates that endovascular treatment is effective and provides durable access circuit survival. Careful patient screening is essential to optimize outcomes.

Modified lyse and wait technique for the treatment of dialysis fistula thrombosis: Percutaneous thrombolytic therapy with a 27-G dental needle

BACKGROUND

The lyse and wait technique is a percutaneous endovascular technique in the treatment of thrombosed dialysis fistulas. In this study, our aim was to introduce a more easily applicable modification of the lyse and wait technique and present our results.

METHODS

A total of 84 patients (56 male; 66.6%), with a mean age of 61 years, were included in the study. The treatment was performed in patients presenting with dialysis fistula thrombosis no more than 1 week before the procedure, whose thrombosed segment length was less than 10 cm. A 27-G dental needle was inserted into the thrombosed segment under ultrasonography guidance, and 5 mg of alteplase was injected in a controlled manner. After about 6 to 12 h, the patients were taken to the angiography unit, and balloon angioplasty was performed.

RESULTS

The technical and clinical success of the procedure was 98.8%. Technical and clinical failure occurred in only one patient. The median primary patency duration was 13.5 months. None of the patients had major complications. At the end of 12 months, the primary patency rate was 66.6%, and the secondary patency rate was 80%.

CONCLUSIONS

Our technique has shown to have high technical and clinical success and patency.

Use of the Covera Stent Graft for the Treatment of Dysfunctional or Thrombosed Arteriovenous Grafts: A Retrospective Analysis of 64 Patients

PURPOSE

To retrospectively evaluate the safety and effectiveness of the Covera stent graft (SG) for the treatment of dysfunctional or thrombosed arteriovenous grafts (AVGs).

MATERIALS AND METHODS

Within 29 months (February 2016-August 2018), 79 patients underwent Covera SG placement in the authors' department for the treatment of dysfunctional AVGs. Data were available for 64 patients who underwent 64 procedures, using 64 devices. Minimum follow-up was 6 months, unless reintervention occurred. Mean follow-up was 277 days (6-923 days). Treatment characteristics were 51 cases with venous-graft anastomosis (VGA) stenosis (79.7%), 13 cases of puncture zone stenosis (20.3%), 14 cases of in SG stenosis (21.9%), 8 cases of pseudoaneurysm treatment (12.5%) (1 treatment area might have had more than 1 characteristic). Thirty-six patients presented with thrombosis (56.2%), and 31 of 64 case were de novo treatment areas (48.4%). Primary outcome measurements were technical success and post-intervention primary patency (PIPP) at 6 months, whereas secondary outcome measurements included factors influencing primary outcome.

RESULTS

Technical success was 100%. Median PIPP was 336 days, and 73.6% of treatment areas were patent at 6 months. There were no significant differences in terms of PIPP when de novo treatment areas were compared with restenotic areas (519 vs. 320 days, respectively; P = .1); patients who presented with versus those who presented without thrombosis (320 vs. 583 days, respectively; P = .07); puncture zone stenosis or elsewhere (329 vs. 686 days, respectively; P = .52); and VGA stenosis or elsewhere (336 vs. 335 days, respectively; P = .9).

CONCLUSIONS

Use of the Covera SG for AVG treatment was safe and effective in every type of treatment area presented in this retrospective analysis.

Long-term results of endovascular treatment for arteriovenous dialysis access thrombosis in 143 patients: A single center experience

Objective:

This study aimed to determine the long-term patency duration and rate of thrombosis of autologous arteriovenous fistulas and synthetic grafts treated with endovascular methods in a large patient population.

Methods:

A total of 144 arteriovenous accesses (37 radiocephalic, 51 brachiobasilic, 41 brachiocephalic, and 15 femorofemoral) from 143 patients were included in the study. A total of 304 endovascular thrombolytic treatment procedures were performed for 94 (65%) arteriovenous fistula and 50 (35%) arteriovenous graft accesses.

Results:

The procedural technical success rate was 98.7%. The mean follow-up duration was 32.5 (range, 3–132) months. The primary patency rates for arteriovenous fistulas and arteriovenous grafts were 78% and 78% at 6 months, 66% and 63% at 1 year, and 45% and 0% at 36 months, respectively. The assisted primary patency rates for arteriovenous fistulas and arteriovenous grafts were 82% and 84% at 6 months, 71% and 69% at 1 year, 51% and 29% at 36 months, and 30% and 1% at 60 months, respectively. The secondary patency rates for arteriovenous fistulas and arteriovenous grafts were 94% and 93% at 6 months, 85% and 85% at 1 year, 58% and 59% at 36 months, and 47% and 48% at 60 months, respectively.

Conclusion:

Although the primary patency durations for arteriovenous fistulas were better after endovascular thrombolytic treatment than those for arteriovenous grafts, the long-term outcomes of assisted primary and secondary patency durations after repeated procedures were similar for both types of arteriovenous accesses.

Comparison of alteplase and urokinase for pharmacomechanical thrombolysis of clotted hemodialysis access

BACKGROUND

Percutaneous pharmacomechanical thrombolysis is increasingly used to salvage thrombosed hemodialysis access. We aim to evaluate the effectiveness of alteplase compared to urokinase in percutaneous pharmacomechanical thrombolysis clotted access.

METHODS

Records of patients who underwent pharmacomechanical thrombolysis at Interventional Nephrology Suite in a tertiary teaching hospital from 1 January 2016 to 31 December 2016 were reviewed. Technical and clinical success rates, thrombosis-free and cumulative survivals, procedure time, and radiation dose imparted to patients were compared for pharmacomechanical thrombolysis with urokinase versus alteplase.

RESULTS

A total of 122 incident patients underwent pharmacothrombolysis (n = 53 for urokinase, n = 69 for alteplase) during the study period. The mean dose of urokinase and alteplase used was 176,897 ± 73,418 units and 3.7 ± 0.8 mg, respectively. Pharmacomechnical thrombolysis using urokinase versus alteplase has similar technical success rate (98.1% vs 97.1%, p = 0.599), clinical success rate (88.7% vs 97.1%, p = 0.068), complication rate (9.4% vs 13.0%, p = 0.373), and primary patency rates at 3 months (57.1% vs 70.1%, p = 0.106). Thrombosis-free survivals of the vascular access were 113.2 (35.3, 196) days versus 122 (84, 239) days (p = 0.168). Cumulative survivals were 239 (116, 320) vs 213 (110.5, 316.5) days (p = 0.801). Procedure time, fluoroscopy time, skin dose, and dose were significantly lower for pharmacomechanical thrombolysis using alteplase compared to urokinase (p = 0.045, p < 0.0001, p = 0.006, p = 0.001, respectively). Stenting was found to be associated with successful dialysis following thrombolysis on univariate analysis (odds ratio: 9.167, 95% confidence interval: 1.391-19.846, p = 0.021), although this was no longer significant in multivariate analysis (p = 0.078).

CONCLUSION

Alteplase is an effective and safe alternative to urokinase for pharmacomechanical thrombolysis of clotted vascular access.

Recent developments in endovascular interventions to sustain vascular access patency in haemodialysis patients

There is amassed evidence regarding the use of endovascular procedures for the treatment of vascular access stenosis and thrombosis. A review was conducted based on available randomized trials, cohort studies and retrospective analyses published after 2000 on endovascular treatment of dysfunctional and thrombosed vascular access, with an aim to illustrate the available device and procedural options. The use of paclitaxel-coated balloons, cutting balloons and covered stents is described in the field of vascular access stenosis. The broad spectrum of available devices and endovascular declotting procedures ranging from thrombolysis to thrombectomy is also discussed. Overall, in this review we demonstrate the increasing role of endovascular procedures in vascular access treatment and the improved patency outcomes provided by the implementation of novel endovascular devices. Moreover, the improvement of post-intervention primary patency rates after endovascular declotting procedures and the shift to more thrombectomy-dependent procedures over time is also highlighted. In conclusion, endovascular treatment of dialysis access stenosis and thrombosis has an established role, owing to the implementation of sophisticated devices, allowing, when needed, the simultaneous treatment of thrombosis and the underlying stenosis.

Ultrasound-Guided Pharmacomechanical Thrombolysis and Angioplasty for Treatment of Acute Thrombotic Prosthetic Arteriovenous Access: 5-Year Experience with 154 Procedures in a Single Center

Pharmacomechanical thrombolysis (PMT) and percutaneous transluminal angioplasty (PTA) for the treatment of acute thrombotic prosthetic arteriovenous access (PAVA) are conventionally guided by radiography, which may cause radiation injury and requires the use of radiographic contrast media. The aim of the present study was to summarize our experience with ultrasound-guided PMT and PTA as an alternative to radiographic guidance. Between December 2012 and October 2016, 114 patients with acute thrombosis of PAVA were treated urgently with ultrasound-guided PMT and PTA to restore blood flow. The patients were followed up every 3 mo postoperatively. The 114 included patients underwent 154 episodes of ultrasound-guided PMT and PTA and were followed up for a mean of 20.7 ± 9.1 mo. The technical success rate was 91.6%, and the clinical success rate was 97.4%. Post-intervention-assisted primary patency rates at 3, 6, 12 and 24 mo were 90.8%, 78.8%, 66.3% and 50.9%, respectively. Post-intervention secondary patency rates at 3, 6, 12 and 24 months were 96.3%, 94.5%, 90.6% and 85.4%, respectively. PMT and PTA for the treatment of PAVA were performed successfully under the guidance of ultrasound with a success rate similar to that under radiographic guidance, thus avoiding radiation injury and contrast medium use, although close surveillance and timely intervention are imperative to ensure long-term patency.