The role of the stent graft is emerging in the management of arteriovenous dialysis access. Physicians are incorporating this device in the management of three distinct problems--vein-graft anastomotic stenosis, pseudoaneurysm formation, and cephalic arch stenosis--with varying degrees of success. Indeed, a recent randomized, controlled trial to evaluate the role of angioplasty plus stent graft versus angioplasty alone for the management of stenosis at the vein-graft anastomosis led to the approval of the stent graft by the Food and Drug Administration; however, several elements of the management of stenosis at the vein-graft anastomosis/cephalic arch as well as the repair of pseudoaneurysms by stent graft remain controversial. The situation is further complicated and warrants a cost-to-benefit ratio analysis when the added cost of the device is appended to the procedure. In contrast to the controversies, angioplasty-induced complete vascular rupture is one situation in which a stent graft is indicated beyond any doubt. With recent conditional Food and Drug Administration approval, it is anticipated that the use of stent grafts might increase in our patients. In this context, it is critically important that nephrologists be familiar with the current controversies and consensus that surround the use of stent grafts for dialysis access. Just as therapeutic interventions are analyzed in other disciplines within nephrology, these experts must appraise the use of this device for dialysis access. This report presents an up-to-date synopsis on the use of the stent graft that would assist renal physicians in requesting or rejecting the device for the optimal management of their patient's vascular access dysfunction.

PURPOSE: To determine the clinical efficacy of stent-graft placement in dysfunctional autogenous hemodialysis fistulas. MATERIALS AND METHODS: Between September 2006 and June 2008, 24 Fluency Plus stent-grafts were inserted in 17 patients with failing autogenous hemodialysis fistulas (two radiocephalic, 12 brachiocephalic, and three brachiobasilic). Six fistulas were thrombosed at presentation. Indications for stent-graft insertion included 10 residual stenoses, six pseudoaneurysms, and one fistuloplasty-induced rupture. Fistula function before and after intervention was assessed with ultrasound dilution technique. RESULTS: The technical success rate was 100%, as were the anatomic and clinical success rates. Via Kaplan-Meier method, the primary access patency rates were 94.1% at 3 months (95% CI, 0.461-0.995) and 88.2% at 6 and 12 months (95% CI, 0.468-0.980). The primary lesion patency rate was 94.1%(95% CI, 0.650-0.992) at 3, 6, and 12 months. The secondary access patency rate had a point estimate of 100% at 3 months, and was 93.8%(95% CI, 0.632-0.991) at 6 and 12 months. Univariate analysis suggested that male sex and left-sided accesses were associated with a longer primary access patency rate (P =.02). The binary restenosis rate at 6 months was 5.9%. Mean transonic flow rates were 667.5 mL/min before intervention and 2,076.0 mL/min after intervention (P =.03, Wilcoxon signed-rank test). No patients were lost to follow-up. CONCLUSIONS: Stent-graft placement in dysfunctional autogenous hemodialysis fistulas is technically feasible and effective in preserving function and preventing access abandonment, with patency rates that exceed historical patency rates with angioplasty and/or uncovered stents.

BACKGROUND: The leading cause of failure of a prosthetic arteriovenous hemodialysis-access graft is venous anastomotic stenosis. Balloon angioplasty, the first-line therapy, has a tendency to lead to subsequent recoil and restenosis; however, no other therapies have yet proved to be more effective. This study was designed to compare conventional balloon angioplasty with an expanded polytetrafluoroethylene endovascular stent graft for revision of venous anastomotic stenosis in failing hemodialysis grafts. METHODS: We conducted a prospective, multicenter trial, randomly assigning 190 patients who were undergoing hemodialysis and who had a venous anastomotic stenosis to undergo either balloon angioplasty alone or balloon angioplasty plus placement of the stent graft. Primary end points included patency of the treatment area and patency of the entire vascular access circuit. RESULTS: At 6 months, the incidence of patency of the treatment area was significantly greater in the stent-graft group than in the balloon-angioplasty group (51% vs. 23%, P<0.001), as was the incidence of patency of the access circuit (38% vs. 20%, P=0.008). In addition, the incidence of freedom from subsequent interventions at 6 months was significantly greater in the stent-graft group than in the balloon-angioplasty group (32% vs. 16%, P=0.03 by the log-rank test and P=0.04 by the Wilcoxon rank-sum test). The incidence of binary restenosis at 6 months was greater in the balloon-angioplasty group than in the stent-graft group (78% vs. 28%, P<0.001). The incidences of adverse events at 6 months were equivalent in the two treatment groups, with the exception of restenosis, which occurred more frequently in the balloon-angioplasty group (P<0.001). CONCLUSIONS: In this study, percutaneous revision of venous anastomotic stenosis in patients with a prosthetic hemodialysis graft was improved with the use of a stent graft, which appears to provide longer-term and superior patency and freedom from repeat interventions than standard balloon angioplasty.(ClinicalTrials.gov number, NCT00678249.) Copyright 2010 Massachusetts Medical Society.

Objectives: The aim of this study was to analyze the risk and consequences of venous rupture during angioplasty of malfunctioning hemodialysis grafts and fistulas. Background: Venous stenoses in the outflow limb of hemodialysis accesses often require ultra-high balloon pressure for optimal dilatation. Methods: Baseline characteristics and outcomes were analyzed for a consecutive series of patients treated between 1999 and 2008. Results: Venous rupture or perforation occurred in 11 of 1242 (0.9%) procedures. No patient with a rupture or perforation died or required emergency or urgent surgical repair. Two of 11 patients (18.2%) required transfusions, 8 of 11 patients (72.7%) required stenting, and 6 of 8 (75.0%) who needed stenting received covered stents to achieve hemostasis. Rupture led to access thrombosis within 30 days in 9 of 11 cases (82%). Multivariable logistical regression analysis suggested that using a balloon catheter more than 2 mm larger than the diameter of the hemodialysis access or using peripheral cutting balloons increased the risk of rupture or perforation. Conclusions: Rupture or perforation is a rare complication of treatment of malfunctioning hemodialysis grafts and fistulas. The complication may be managed with nonsurgical methods and might be avoided by optimal balloon selection and sizing.(c) 2009 Wiley-Liss, Inc.

We report the case of a 66-year-old female who presented with jaundice secondary to recurrent adenocarcinoma of the gallbladder and several common bile duct stones. Percutaneous papillary dilatation was planned to remove the common bile duct stones. Papilla was dilated through the percutaneous approach with an 8-mm peripheral cutting balloon instead of a standard balloon. All the stones were pushed successfully into the duodenum with a saline flush. No complications were encountered. Use of a peripheral cutting balloon for dilatation of the papilla seems to be safe and effective because it has the advantage of controlled incision and dilatation of the target at low pressures.

PURPOSE: To evaluate the safety and feasibility of cryoplasty as the initial balloon treatment for dialysis access venous stenoses. MATERIALS AND METHODS: Twenty patients with grafts (n = 18) or arteriovenous fistulas (n = 2) were enrolled in an institutional review board-approved prospective study. Patients with high venous dialysis pressures (n = 7), poor flow (n = 3), abnormal thrill (n = 3), nonmaturation (n = 2), poor clearance (n = 2), edema (n = 1), prolonged bleeding (n = 1), or recurrent clotting (n = 1) in the presence of stenoses >/= 50% were eligible. Mean stenosis measurement was 62.8%(range, 51%-82%). Mean lesion length was 2.57 cm (range, 0.4-5.7 cm). Device success required complete cryoplasty balloon expansion. Procedure success required anatomic success combined with a clinical or hemodynamic indicator of success. Primary circuit patency ended with any restenosis. Primary lesion patency ended with index lesion restenosis. RESULTS: The device success rate was 53%(nine of 17). The anatomic success rate after cryoplasty was 35%(seven of 20). Eighty percent of lesions (16 of 20) were treated with conventional percutaneous transluminal angioplasty (PTA) balloons after cryoplasty. The procedure success rate after supplemental PTA was 80%(16 of 20). The primary circuit patency rates were 82%(14 of 17) at 3 months and 19%(three of 16) at 6 months. The primary lesion patency rates were 88%(15 of 17) at 3 months and 25%(four of 16) at 6 months. All patients reported pain during cryoplasty, and the 16 who underwent supplemental PTA described cryoplasty as more painful than PTA. Cryoplasty-related complications included one case of transient spasm. CONCLUSIONS: Use of the PolarCath peripheral balloon catheter system as the initial balloon for dialysis access venous stenoses is safe but painful. Anatomic success rates after cryoplasty are low. Results of cryoplasty supplemented by PTA appear comparable to those of PTA alone.

PURPOSE: To compare the technical success, safety, and patency of cutting balloon angioplasty versus high-pressure balloon angioplasty in the treatment of resistant native hemodialysis fistula stenoses. MATERIALS AND METHODS: The authors retrospectively reviewed 1,220 percutaneous transluminal angioplasty procedures performed to treat dysfunctional native hemodialysis fistulas. Seventy patients with stenoses resistant to conventional balloon angioplasty (up to 24 atm) were included in this study: 35 patients underwent cutting balloon angioplasty from September 2003 through February 2005, and 35 patients underwent high-pressure balloon angioplasty from March 2005 through April 2006. Evaluation included technical success, complications, and postintervention patency rates up to 6 months. RESULTS: The technical success rates were similar between the cutting balloon (100%) and high-pressure balloon (97.1%) groups. After cutting balloon angioplasty, the primary lesion patency rates were 100%(35/35), 88.6%(31/35), and 71.4%(25/35) at 1 month, 3 months, and 6 months, respectively. After high-pressure balloon angioplasty, the primary lesion patency rates were 97.1%(34/35), 62.9%(22/35), and 42.9%(15/35) respectively. The primary lesion patency rates at 3 and 6 months were significantly better with cutting balloon angioplasty than with high-pressure balloon angioplasty (P =.018 and .009, respectively). There were no device-related complications in the cutting balloon group. Six device-related extravasations occurred in the high-pressure balloon group. CONCLUSIONS: The results of this retrospective study suggest that, for resistant stenoses in native hemodialysis fistulas, both high-pressure balloon and cutting balloon angioplasty are effective; however, cutting balloon angioplasty seems to provide more long-standing primary patency at 6-month follow-up.

OBJECTIVES: To evaluate the technical success, safety and patency of cutting balloon angioplasty for the treatment of resistant dialysis access stenoses. BACKGROUND: Cutting balloon angioplasty has been proposed to be useful in treating resistant dialysis access stenoses. However, they are based on experience with very limited cases and formal patency data is insufficient. METHODS: The author retrospectively reviewed 896 percutaneous transluminal angioplasty (PTA) procedures for the treatment of dysfunctional or thrombotic dialysis access. Thirty-seven of 623 patients with native fistulas and 23 of 273 patients with synthetic grafts had residual stenoses of more than 30% after conventional PTA at an inflation pressure of 24 atm for 60 sec. In these 60 patients, additional cutting balloon PTA was performed. RESULTS: The overall technical success rate was 96.7% and clinical success rate was 98.3%. Only one patient experienced mild local extravasation. The postintervention primary patency rates for native fistula group (N = 37) were 100%, 86.4%, and 67.5% at 1-month, 3-month, and 6-month; the postintervention primary patency rates for synthetic graft group (N = 23) were 87.0%, 60.9%, and 34.2% at 1-month, 3-month, and 6-month respectively. CONCLUSIONS: For resistant venous stenoses of dialysis access, cutting balloon PTA is effective, safe, and seems to provide comparative primary patency as suggested by guidelines.

The Kidney Dialysis Outcomes Quality Initiative guidelines and the Fistula First Initiative for vascular access have had a measurable impact on the incidence and prevalence of the type of access used to deliver hemodialysis in the United States. There has been a yearly increase in the placement of arteriovenous fistulas and an exponential increase in endovascular treatment of failing and immature fistulas. Undoubtedly, the predominant cause of fistula malfunction is stenosis within the access system. The stenotic lesions can occur anywhere within the access system from the arteries to the outflow and central veins. One of the relatively common sites for stenosis in patients with brachiocephalic fistulas is the cephalic arch region. While access stenoses at many other sites have been successfully treated with percutaneous balloon angioplasty, the results of this approach in the management of cephalic arch stenosis (CAS) have been rather disappointing. This has been in part due to multiple factors including the resistant nature of the stenosis, the development of early restenosis, as well as poor patency and high vein rupture rates. This article discusses the anatomy, postulated etiology and percutaneous interventions for the treatment of CAS. In addition, the report highlights surgical alternatives to the management of stenosis in this segment of the cephalic vein.

AIM: To evaluate the technical success and patency rates following primary cutting balloon angioplasty for venous stenoses in native dialysis fistulas. METHODS: Forty-one patients (26 men, 15 women; age range 26-82 years, average age 59 years) underwent 50 (repeat procedures in 9 patients) primary cutting balloon (PCB) angioplasty procedures in three institutions by three primary operators. The indication was primary stenosis in 21 patients, recurrent lesions in 15, and immature fistulas in 5. A PCB was used alone in 17 cases, but was followed by a larger standard balloon in 33 cases. Follow-up included ultrasound, flow analysis and urea reduction ratio, and ranged from 2 to 30 months (mean 14 months). RESULTS: The technical success rate was 98%. All procedures were relatively painless. Two PCBs burst and 4 leaked, but without causing any morbidity. Nineteen fistulas were still working at last follow-up. Primary patency rates at 6, 12, and 24 months using Kaplan-Meier analysis were 88%, 73%, and 34%, respectively, and the primary assisted patencies were 90%, 75%, and 50%, respectively. CONCLUSION: PCB angioplasty has high technical success and low complication rates. The long-term patency rates are favorable for PCB angioplasty and compare favorably with other series.

Purpose To compare the postintervention primary patency rates of cutting balloon angioplasty (CBA) with those of conventional percutaneous transluminal angioplasty (PTA) in the treatment of hemodialysis-related stenoses at least 2 cm long. Materials and Methods This retrospective and controlled study included 29 patients with a hemodialysis-related stenosis at least 2 cm long. From August 2002 to August 2003, nine patients (PTA group, six upper-arm and three forearm fistulas) were treated with a conventional balloon (5-8 mm, 4 cm long). From September 2003 to December 2005, 20 patients (CBA group, 12 upper-arm and seven forearm fistulas; one polytetrafluoroethylene hemodialysis graft) were treated with a cutting balloon (5-7 mm, 1 cm long). The median follow-up was 22.1 months for the CBA group and 15.6 months for the PTA group. The Kaplan-Meier method was used to calculate the primary cumulative patency rates, and the log-rank test was used for comparison. Multivariate Cox models were generated by combining three variables: patient age, stenosis length, and treatment type (CBA or PTA). Results In the CBA group, the postintervention primary patency was 85%+/- 16 at 6 months, 70%+/- 20 at 1 year, and 32%+/- 26 at 18 months. In the PTA group, the postintervention primary patency was 56%+/- 32 at 6 months and 21%(range, 0%-53%) at 1 year. When comparing PTA versus CBA with the log-rank test, there was a statistically significant difference (P =.009). With the multivariate Cox models, treatment was again a statistically significant (P =.007) determinant of primary patency; patient age and stenosis length were not. Conclusion The use of a cutting balloon as the first-line treatment for stenoses at least 2 cm long significantly improves the postintervention primary patency rate.

The prevalence of end-stage renal disease in Singapore is high and rising with some 2,700 patients requiring haemodialysis in the year 2004. In tandem with the increasing prevalence of diabetes mellitus, the number of dialysis patients is projected to rise to nearly 6,000 in the year 2010, adding to the national healthcare costs. Diabetic nephropathy accounts for about 40 percent of patients starting dialysis in Singapore. There have been few studies regarding vascular access for haemodialysis, despite its great demand in the local population. These vascular access channels are far from perfect, and provide great challenges for the vascular surgeons, nephrologists and interventional radiologists on a constant basis. The concomitant vasculopathies in diabetic patients also increase the risk of morbidity related to vascular access interventions. This paper will review the current state of interventions and research associated with managing venous stenosis in renal vascular access for haemodialysis.