Single-center experience with the Arrow-Trerotola Percutaneous Thrombectomy Device in the management of thrombosed native dialysis fistulas

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.

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.

Comparing Patency Rates of Arteriovenous Dialysis Access following Percutaneous Thrombectomy Using Various Catheter Directed Therapies

BACKGROUND

Arteriovenous fistulas often require frequent interventions to maintain patency for hemodialysis. Interventions may include open or percutaneous thrombectomy with additional targeted interventions as indicated. We evaluated the primary and cumulative functional patency rates following three unique approaches to percutaneous thrombectomy of thrombosed dialysis access.

METHODS

A retrospective review of 236 unique patients who presented with thrombosed hemodialysis access was analyzed over a period of 4 years from 2016 to 2020. We analyzed a total of 413 procedures that utilized 3 separate percutaneous thrombectomy devices to assist with restoring patency. The Indigo System CAT-D Aspiration Thrombectomy Catheter (Penumbra; Alameda, CA), the Arrow-Trerotola Rotational Thrombectomy System (Teleflex; Wayne, PA) and the Angiojet Rheolytic Thrombectomy Catheter (Boston Scientific, Marlborough, MA) devices were compared for primary and cumulative functional patency. Primary patency was defined as time from percutaneous thrombectomy to next intervention (Angioplasty, stenting, and repeat thrombectomy). Cumulative functional patency was defined as time from percutaneous thrombectomy to time of access abandonment. Medical record chart review was utilized to determine patency rates.

RESULTS

A total of 413 percutaneous thrombectomy procedures were performed. Of the procedures performed, 98 utilized Angiojet, 103 utilized Trerotola, and 212 used Penumbra. The mean primary patency rates in (days) for the devices were as follows: Angiojet (194), Trerotola (204), and Penumbra (107). The mean cumulative functional patency rates (in days) for the devices were as follows: rheolytic thrombectomy (450 days), aspiration thrombectomy (292 days), and rotational thrombectomy (475 days). Angiojet versus Penumbra and Trerotola versus Penumbra both showed diminished patency rates when using the Penumbra catheter that were statistically significant (P < 0.05).

CONCLUSIONS

All percutaneous thrombectomy approaches do not result in the same primary or cumulative functional patency rates. Approaches with Trerotola and Angiojet resulted in improved primary and cumulative functional patency rates compared to those using Penumbra.

Cleaner XT Rotational Thrombectomy: An Efficacious Endovascular Technique for Salvage of Thrombosed Arteriovenous Access and a 12 Month Outcome Analysis

Purpose:

This study aims to describe an efficacious method using Cleaner XT rotational thrombectomy with catheter-directed thrombolysis and drug-eluting balloon angioplasty for the salvage of thrombosed arteriovenous fistulae and grafts.

Materials and Methods:

Retrospective analysis of all patients with thrombosed hemodialysis accesses who underwent endovascular salvage using the Cleaner XT rotational thrombectomy system at a single institution between June 2019 and September 2020 was performed. Patency was presented as Kaplan-Meier survival curves, and regression analysis was performed to examine predictors of postintervention primary patency and assisted primary patency based on Cox proportional-hazards model.

Results:

Thirty-four patients with thrombosed accesses underwent Cleaner XT rotational thrombectomy between June 2019 and September 2020. Technical and clinical success were both 100%. Mean procedure time was 62 ± 20 minutes. Mean postintervention primary patency time was 152 ± 51 days; 30, 90, 180, and 365 day postintervention primary patency rates were 89%, 80%, 68%, and 56%, respectively. Mean postintervention-assisted primary patency time was 157 ± 59 days; 30, 90, 180, and 365 day postintervention-assisted primary patency rates were 91%, 82%, 71%, and 59%, and 180 and 365 day secondary patency rates were 97.2% and 94.4%, respectively.

Conclusion:

The Cleaner XT rotational thrombectomy device demonstrates excellent clinical and technical success rates, with good patency results at all time points up to 12 months postintervention.

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.

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.

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.

Treatment of the acute severe pulmonary embolism using endovascular methods

Purpose

To present a single-centre experience with endovascular treatment of patients with severe symptoms secondary to acute pulmonary embolism (PE).

Material and methods

Twenty-five patients were treated due to contraindications or deficient effects of systemic thrombolytic therapy. The patients were treated with a combination of fragmentation and aspiration, only aspiration, or only fragmentation, and with catheter-directed thrombolytic therapy.

Results

The saturation was improved following treatment in all patients, except in one where the procedure could not be completed. There were no immediate or late procedure-related complications.

Conclusions

Endovascular treatment of severe PE is a safe and efficient option in patients with failing effect or contraindication to systemic thrombolysis.

Definitions and End Points for Interventional Studies for Arteriovenous Dialysis Access

This paper is part of the Clinical Trial Endpoints for Dialysis Vascular Access Project of the American Society of Nephrology Kidney Health Initiative. The purpose of this project is to promote research in vascular access by clarifying trial end points which would be best suited to inform decisions in those situations in which supportive clinical data are required. The focus of a portion of the project is directed toward arteriovenous access. There is a potential for interventional studies to be directed toward any of the events that may be associated with an arteriovenous access' evolution throughout its life cycle, which has been divided into five distinct phases. Each one of these has the potential for relatively unique problems. The first three of these correspond to three distinct stages of arteriovenous access development, each one of which has been characterized by objective direct and/or indirect criteria. These are characterized as: stage 1-patent arteriovenous access, stage 2-physiologically mature arteriovenous access, and stage 3-clinically functional arteriovenous access. Once the requirements of a stage 3-clinically functional arteriovenous access have been met, the fourth phase of its life cycle begins. This is the phase of sustained clinical use from which the arteriovenous access may move back and forth between it and the fifth phase, dysfunction. From this phase of its life cycle, the arteriovenous access requires a maintenance procedure to preserve or restore sustained clinical use. Using these definitions, clinical trial end points appropriate to the various phases that characterize the evolution of the arteriovenous access life cycle have been identified. It is anticipated that by using these definitions and potential end points, clinical trials can be designed that more closely correlate with the goals of the intervention and provide appropriate supportive data for clinical, regulatory, and coverage decisions.

Arterial Embolism Occurring During Percutaneous Thrombectomy of Dialysis Graft

PURPOSE

To evaluate the incidence, management methods and follow-up results of arterial embolism during percutaneous thrombectomy of hemodialysis grafts.

MATERIALS AND METHODS

After Institutional Review Board approval, the radiologic database of our department for percutaneous thrombectomy procedure in hemodialysis access was retrospectively reviewed. Between 1998 and June 2014, 2975 percutaneous thrombectomy procedures using thromboaspiration technique were performed in 1524 patients with thrombosed hemodialysis grafts. After thrombectomy, angioplasty was performed for significant stenoses. The incidence of arterial embolism was analyzed according to the location/shape of the arteriovenous graft. Percutaneous management methods of arterial embolism and long-term follow-up results by fistulography were also evaluated.

RESULTS

Arterial embolism was documented by angiography in 117 cases (3.9%). Of these, three were symptomatic and subsided after embolectomy. The incidence was significantly correlated with the location/shape of the graft (p = 0.001). Arterial emboli were retrieved using occlusion balloon/Fogarty balloon (n = 58), guiding catheter-assisted aspiration (n = 36), sheath-assisted aspiration (n = 2) and back-bleeding technique (n = 3). Others were observed without intervention (n = 17) or surgically removed (n = 1). Arterial emboli were completely retrieved in 86 cases and partially retrieved in 13 cases. Ulnar artery rupture occurred in one case due to over-inflation of the occlusion balloon. Follow-up fistulography performed in 60 patients among whom 99 percutaneous embolectomies were done revealed arterial stenosis/occlusion in 7 and residual emboli in one patient. In observed patients without intervention, follow-up documented complete resolution of the emboli without arterial stenosis in 9 patients.

CONCLUSION

Radiologically perceivable arterial embolism is uncommon during percutaneous thrombectomy of thrombosed dialysis grafts. The majority of the emboli can be retrieved by percutaneous techniques, but may induce arterial damage in some patients. Clinical observation can be another option for patients without ischemic symptoms.

Maintaining Patency of Vascular Access for Haemodialysis

All types of vascular access, a necessity for haemodialysis, are prone to thrombosis and if untreated this results in failure. Thrombosis results from the combination of impaired blood flow, endothelial and vessel wall injury and a propensity towards pro-coagulative states, either intrinsic or aggravated by dialysis or dehydration. The treatment of access thrombosis relies on removal of the clot (thrombectomy) and treatment of the underlying problem. In most cases this is stenosis secondary to neointimal hyperplasia which can occur early (failure to mature) or later. Pharmacological approaches have largely been shown to be ineffective at prevention of thrombosis. The mainstay of preventing access failure may be in surveillance and detecting stenosis prior to occlusion although the optimal protocol to achieve this remains undefined. Management of thrombosed access is via either surgical and radiological approaches. Multiple techniques and devices are available for thrombectomy and the choice is usually based on local expertise and availability rather than evidence as few trials have been performed to allow robust comparisons. This paper outlines the basis of access thrombosis and discusses the currently available techniques for treatment.

Initial clinical use of a novel mechanical thrombectomy device, XCOILTM, in hemodialysis graft and fistula declot procedures

PURPOSE

We aimed to evaluate the safety and effectiveness of a novel catheter-based mechanical thrombectomy device, XCOILTM, as a first line therapy to restore patency of thrombosed dialysis grafts and fistulae.

METHODS

In 2010, 18 consecutive/sequential patients (11 male, 7 female; median age, 52 years; age range, 32-69 years) with occluded arteriovenous grafts (n=15) or fistulae (n=3) were treated with XCOILTM (NexGen Medical Systems Inc.) without adjunctive thrombolytic drugs. XCOILTM was advanced distal to the thrombus within the outflow vein as well as distal to the arterial inflow platelet thrombin plug, using a 4F angiographic catheter. The percentage of thrombus cleared, primary patency, procedure time, and XCOILTM performance were documented.

RESULTS

Thrombosis occurred 1-30 days prior to the procedure. Thrombosed segments of graft/fistula measured 10-50 cm. Pre- and postprocedure angiography demonstrated that in 15 of 18 cases (83%) XCOILTM removed 80%-100% of the venous outflow thrombus. In 11 of 14 cases (79%), the platelet thrombin plug was also removed. Thrombectomy procedure time averaged 8 min, with one to three passes with the XCOILTM required. No evidence of distal embolization or graft/vessel injury was found on angiography following clot removal. In four cases in whom patency was not restored with XCOILTM, subsequent use of other clot removal devices also failed to restore patency. In one case with severe venous stenosis, the device failed to deploy and the thrombus was not captured. No intraprocedural complications related to XCOILTM use occurred.

CONCLUSION

XCOILTM is an effective and safe first-line therapy option for the treatment of thrombosed hemodialysis grafts/fistulae. Rapid removal of intact thrombus and platelet thrombin plug can be achieved without adjunctive thrombolytics.

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.

Percutaneous Rheolytic Thrombectomy of Thrombosed Autogenous Dialysis Fistulas

Purpose: To retrospectively analyze the technical and clinical outcome of percutaneous rheolytic thrombectomy with the use of the AngioJet device in thrombosed autogenous arteriovenous dialysis fistulas. Methods: A cohort of 38 consecutive patients (24 men; mean age 70.7±13.8 years) presenting with 59 thrombotic events in 39 autogenous dialysis fistulas were retrospectively analyzed. The AngioJet rheolytic thrombectomy device was used in all cases. Adjunctive therapies, as well as procedure-related complications, were noted. Primary, assisted primary, and secondary patency of the autogenous fistulas was assessed along with factors potentially influencing patency. Results: Initial technical success to recanalize the efferent vein was 100% (n=59), and a successful postprocedure dialysis session was possible in 97% (n=57) of cases. Adjunctive procedures included percutaneous thromboaspiration (n=4, 7%), balloon angioplasty (n=59, 100%), and stent placement (n=16, 27%). Complications related to thrombectomy occurred in 3 (5%) procedures (distal arterial embolus). Primary, assisted primary, and secondary patency rates at 12 months were 56.1% (95% CI 42.8% to 75.2%), 61.6% (95% CI 48.6% to 74.7%), and 86.2% (95% CI 74.9% to 97.5%), respectively. Risk factors for early fistula occlusion were greater patient age (p=0.045), the age of the fistula (p=0.045), previous stent insertion (p=0.019), and an upper arm fistula (p=0.047). Conclusion: Percutaneous rheolytic thrombectomy of autogenous dialysis fistulas is effective in restoring patency and allowing subsequent hemodialysis. The complication rate is acceptably low, and the large majority of the fistulas are still used for hemodialysis at 1-year follow-up. Older fistulas and upper arm fistulas are at higher risk for early rethrombosis.

Outcomes of percutaneous interventions in transposed hemodialysis fistulas compared with nontransposed fistulas and grafts

PURPOSE

To compare postpercutaneous intervention outcomes of autogenous venous-transposition arteriovenous fistulas (AVFs) versus those of autogenous nontransposed AVFs (nAVFs) and prosthetic arteriovenous grafts (AVGs).

MATERIALS AND METHODS

A total of 591 hemodialysis accesses (195 transposed AVFs [tAVFs], 205 nAVFs, 191 AVGs) in 522 patients (278 male; mean age, 57 y; range, 15–91 y) underwent percutaneous transluminal angioplasty (PTA) and/or mechanical thrombectomy (ie, declotting). Access characteristics, surgical history, percutaneous interventions, postinterventional primary and secondary access patency, and follow-up data were collected. Cox proportional-hazards regression analyses, Fisher exact tests, and χ2 tests were performed.

RESULTS

Mean follow-up period was 32 months. Mean access ages at initial percutaneous intervention were 260 days (tAVF), 206 days (nAVF), and 176 days (AVG; P < .01). One-year postinterventional primary patency (PIPP) rates were 25% (tAVF), 24% (nAVF), and 14% (AVG). One-year postinterventional secondary patency (PISP) rates were 77% (tAVF), 61% (nAVF), and 63% (AVG). Median PIPP durations were 138 days (tAVF), 121 days (nAVF), and 79 days (AVG; P = .0001). Median PISP durations were 1,076 days (tAVF), 783 days (nAVF), and 750 days (AVG; P = .019). Total interventions needed to maintain PISP were 2.4 (tAVF), 1.3 (nAVF), and 3.2 (AVG) per patient-year (P < .001), which included 1.9, 1.2, and 1.4 PTAs (P < .01) and 0.45, 0.15, and 1.8 declotting procedures, respectively (P < .001).

CONCLUSIONS

Based on the number of percutaneous interventions needed to maintain PISP, these results confirm the current Dialysis Outcomes Quality Initiative access preference of nAVFs before tAVFs before AVGs. tAVFs offered superior postinterventional outcomes than AVGs. With additional interventions, tAVFs could even outperform nAVFs in terms of PISP.

Thromboaspiration of arteriovenous hemodialysis graft thrombosis using Desilets-Hoffman sheath: single-center experience

PURPOSE

The purpose of this study was to evaluate the feasibility, efficacy and safety of percutaneous thromboaspiration with a 7F Desilets-Hoffman sheath compared with previously established percutaneous mechanical thrombectomy techniques in occluded hemodialysis grafts.

MATERIALS AND METHODS

One thousand three hundred five patients (767 women, 538 men; mean age, 61.04±13.09 years; mean graft age, 36.64±30.80 mo) with 2,531 episodes of hemodialysis graft thrombosis underwent percutaneous thromboaspiration with a 7F Desilets-Hoffman sheath using criss-cross or apex puncture technique. Technical success rate, procedure time, complications and patency rates were analyzed.

RESULTS

Technical success was achieved in 2,426 of 2,531 procedures (95.9%). Average procedure time of the intervention was 42.87±22.77 minutes. Primary patency rate was 61.9% at 3 mo, 41.2% at 6 mo and 19.6% at 1 year. Major complications occurred in 4.1% of cases (23 graft outflow rupture; 68 arterial emboli; 1 arterial dissection; 3 symptomatic pulmonary embolism; 1 stent migration) and minor complications occurred in 7.7% of cases (196 cases). These results were comparable to previously reported mechanical thrombectomy techniques in occluded hemodialysis grafts.

CONCLUSIONS

Percutaneous thromboaspiration of occluded hemodialysis grafts with a Desilets-Hoffman Sheath is an effective and safe method.

Disconnection of the rubber tip of arrow-trerotola percutaneous thrombolytic device

A rubber tip disconnection of Arrow-Trerotola percutaneous thrombolytic device (PTD) may occur occasionally. We experienced 5 cases of a rubber tip disconnection among 453 mechanical thrombectomy sessions with the use of PTD. We present a report about these five cases and suggest possible causes for the occurrences.

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.

Hybrid surgery versus percutaneous mechanical thrombectomy for the thrombosed hemodialysis autogenous arteriovenous fistulas

Purpose

For the successful treatment of thrombosed autogenous arteriovenous fistula (AVF), we designed and performed a hybrid surgery. Its clinical outcomes were compared with those of percutaneous mechanical thrombectomy, retrospectively.

Methods

Forty cases of thrombosed autogenous AVFs underwent hybrid surgery, whereas 19 cases received percutaneous mechanical thrombectomy. Hybrid surgery consisted of surgical thrombectomy, balloon angioplasty and/or additional surgical angioplasty. Percutaneous mechanical thrombectomy included catheter-introduced thrombus aspiration, balloon angioplasty and/or stenting. Procedure related outcomes such as technical success rates and primary patency rates were analyzed, retrospectively.

Results

There were no statistically significant differences between the two groups in terms of demographic data of the patients including age, gender, diabetes status, and frequency of antiplatelet use, as well as the characteristics of thrombosed autogenous AVFs such as access age, site, type, and length of time between thrombosis and AVF creation (P > 0.05). Technical success rates (92.5% vs. 68.4%, P = 0.005, respectively) and primary patency rates (85.9% vs. 36.8% at 6 months, 81.1% vs. 26.3% at 12 months, 81.1% vs.21.1% at 18 and 24 months respectively, log-rank test, (P < 0.001) were significantly higher in the hybrid surgery group. In terms of cost analysis, supply cost was not different (P = 0.065), but total cost was statistically lower in the hybrid surgery group (P = 0.019).

Conclusion

Hybrid surgery showed better technical success rates and patency rates in the salvaging of thrombosed autogenous AVFs than in percutaneous mechanical thrombectomy.

Percutaneous treatment of thrombosed arteriovenous fistulas: clinical and economic implications

BACKGROUND AND OBJECTIVES

Maintenance of previously thrombosed arteriovenous fistulas (AVFs) as functional vascular accesses can be highly expensive, with relevant financial implications for healthcare systems. The aim of our study was to evaluate the costs and health outcomes of vascular access care in hemodialysis patients with AVF thrombosis.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A retrospective, controlled cohort study was performed among local hemodialysis patients with completely thrombosed AVFs between August 1, 2007, and July 1, 2008. Detailed clinical and demographic information was collected and a comprehensive measure of total vascular access costs was obtained. Costs are reported in 2009 U.S. dollars.

RESULTS

A total of 63 consecutive hemodialysis patients with thrombosed AVFs were identified--a cohort of 37 patients treated with percutaneous thrombectomy and a historic cohort of 25 patients with abandoned thrombosed AVFs. The mean cost of all vascular access care at 6 months was $2479. Salvage of thrombosed AVFs led to a near two-fold reduction in access-related expenses, per patient-month at risk ($375 versus $706; P = 0.048). The costs for access-related hospitalizations ($393 versus $91; P = 0.050), management of access dysfunction ($106 versus $28; P = 0.005), and surgical interventions ($35 versus $6; P = 0.001) were also significantly lower in the percutaneous treatment group. At 6 months, most of these patients had a functional AVF as permanent vascular access (91% versus 33%, P = 0.0001).

CONCLUSIONS

Salvage of thrombosed AVF is a highly efficient procedure; therefore, intensive efforts should be undertaken to universalize these interventions.

Radial arterial approach with adjunctive urokinase for treating occluded autogenous radial-cephalic fistulas

There are no data regarding the feasibility and safety of a radial arterial approach with adjunctive urokinase for treating occluded autogenous radial-cephalic fistulas. We retrospectively examined 54 transradial interventions performed to treat occluded autogenous radial-cephalic fistulas within 72 h of occurrence. Urokinase was used in patients with a large thrombus burden. A total of 92 lesions in 54 consecutive patients (27 males, 27 females; mean age, 61.8+/-12.3 years) were treated via radial access. All radial punctures were successful except in one patient. Most thrombotic lesions were located within 1 cm of the radiocephalic anastomosis (79.6%). The mean length of treated thrombotic lesions was 10.3+/-5.4 cm (range, 4-32 cm). Twenty-five patients (46.3%) received urokinase (mean dose, 96,000+/-30,000 U). After transradial intervention, systolic, diastolic, and mean pressures in the radial artery decreased from 179+/-41, 77+/-17, and 111+/-22 mm Hg to 71+/-29, 36+/-15, and 48+/-19 mm Hg (all p's\0.001), respectively. Four radial interventions were unsuccessful. The anatomic and clinical success rates of the radial approach were both 92.6%; postinterventional primary patency rates were 65% at 6 months and 40% at 12 months. Two minor vascular complications were noted, one caused by guidewire-induced contrast extravasation and the other by balloon-induced contrast extravasation. No patient developed clinical signs of pulmonary embolism. In conclusion, the radial approach with adjunctive urokinase is an effective and safe approach to treat occluded autogenous radial-cephalic fistulas.

Surgical or endovascular repair of thrombosed dialysis vascular access: is there any evidence?

INTRODUCTION

Endovascular and surgical strategies have been used to manage patients with thrombosed vascular access for hemodialysis. We analyzed the evidence to see whether endovascular or surgical treatment has the best outcome in terms of primary success rate and long-term patency.

METHODS

We performed a systematic literature search of endovascular and surgical repair of thrombosed hemodialysis vascular access. The analysis included meta-analysis, randomized, and population-based studies of thrombosed arteriovenous fistulae and grafts.

RESULTS

One meta-analysis and eight randomized studies on the treatment of arteriovenous graft thrombosis were identified. Studies conducted before 2002 demonstrated a significantly better primary success rate and primary and secondary patencies of surgical thrombectomy vs endovascular intervention. After 2002, similar results of both techniques have been reported. Only population-based studies on the treatment of thrombosed autogenous arteriovenous fistulae have been published, showing similar outcome of surgical and endovascular intervention in terms of primary success. The long-term primary and secondary patencies are slightly better for surgical treatment, but this concerns only forearm fistulae.

CONCLUSIONS

The outcome of endovascular and surgical intervention for thrombosed vascular access is comparable, in particular for thrombosed prosthetic grafts. Surgical treatment of autogenous arteriovenous fistulae is likely to have benefit compared with endovascular means. Definitive randomized trials are needed to provide the level 1 evidence to resolve this latter issue.

Predictors of early dialysis vascular-access failure after thrombolysis

BACKGROUND

Vascular-access patency is critical for effective and uninterrupted haemodialysis. Limited literature exists evaluating if a surgical or repeated radiological approach is superior for reocclusion following failure of radiological recanalization. Few consistent early predictors of failure have been identified after radiological intervention for thrombosed vascular access.

METHODS

138 patients with thrombosed arteriovenous fistulas or prosthetic grafts treated by radiological intervention, over 10 years, were retrospectively investigated. Reocclusion was treated by either repeated thrombolysis or surgery. Radiological patency rates, after first and second episodes of access thrombosis at 12 months after intervention were analysed. Surgical and radiological patency rates for second access thrombosis were compared. The Cox and logistic regression models were used to identify potential factors associated with reocclusion.

RESULTS

In patients who experienced reocclusion within 1 month after radiological intervention, the 3-month repeated radiological patency rate (n = 13) was 38.5%, compared to a 60% surgical patency rate (n = 10), but this did not reach statistical significance. Radiological patency rates after first access thrombosis at 3 and 12 months were 56.6 and 39.5%, respectively. In contrast, radiological patency rates after a second access thrombosis were 51.1 and 24.4%, respectively; a statistical difference in success was not achieved. Native arteriovenous fistulas were 3.23 times as likely to remain patent over 12 months following a first radiological intervention (p < 0.02) and less likely to experience a second reocclusion event (p < 0.01). Anticoagulation was associated with a lower risk of second reocclusion, whilst a history of venous thrombosis was associated with a greater risk (p < 0.02).

CONCLUSION

Surgery achieves superior patency rates compared to repeated radiological interventions and should be considered if reocclusion occurs within a month following radiological thrombolysis.