Restoring arteriovenous access: Pilot study using a scoring balloon in 50 patients

Background: Arteriovenous access failure is most often due to the development of neointimal hyperplastic stenoses. Balloon angioplasty remains standard of care for endovascular treatment of stenoses obstructing blood flow in hemodialysis fistulas and grafts. Scoring balloon technologies have been developed to disrupt the atheromatous plaque and have shown to be safe and effective for treating stenosis in the hemodialysis access circuit. However, improvement in patency has yet to be established. Methods: This prospective, single-arm study included 50 patients with stenosed hemodialysis fistula/grafts treated with the AngioSculpt® scoring balloon (Philips) and followed for 6 months. The primary endpoint was target lesion primary patency at 2 and 6 months defined as freedom from re-intervention. Results: Treatment with the scoring balloon resulted in a reduction in stenosis from 78% ± 13.36% to 7.2% ± 7.57% (mean ± standard deviation). Scoring balloon inflation pressures averaged 11.4 atm; no slippage/dissections occurred. After 2 months, 10% of patients required re-intervention. At 6 months, 19% of patients required re-intervention. The 6-month freedom from re-intervention rate was higher for patients with stenosed fistulas (83.3%) compared to patients with stenosed grafts (71.4%). Six-month patency rates were highest for patients with no or one previous intervention (91.6% and 90.0%, respectively); patients with two to five preceding interventions had a 6-month patency rate of 80%, and those with more than five previous interventions had a 50% 6-month patency rate. Conclusion: Results from this pilot study suggest that the AngioSculpt scoring balloon may be a viable treatment option for stenosed arteriovenous fistula/graft access.

Measuring the palpable pulsatility length as a physical examination test in defining the severity of inflow stenosis for hemodialysis fistulas

Background Pulsatility is an important property of hemodialysis arteriovenous fistulas (AVF) and can be perceived by the fingers as a gradual decrease in strength downstream from the anastomosis along the main trunk of the fistula. The distance from the point at which the pulse becomes imperceptible to the anastomosis is termed the palpable pulsatility length (PPL); we considered this length may play a role in assessing the severity of inflow stenosis for hemodialysis fistulas. Methods This study was performed by retrospective analysis of routinely collected data. Physical examinations and fistula measurements were performed in a selected population of 76 hemodialysis patients with mature fistulas during half a year. Fistula measurements included the PPL before and after treatment and the distance between the anastomosis and the arterial cannulation site (aPump length). The aPump index (API) was calculated by dividing the PPL by the aPump length. Angiograms were reviewed to determine the location and severity of stenosis. PPL and API were used to detect the critical inflow stenosis, which indicates severe inflow stenosis of an AVF. Results Receiver operating characteristic analysis showed that the area under the curve was 0.895 for API and 0.878 for PPL. A cutoff value of API < 1.29 and PPL < 11.0 cm were selected to detect the critical inflow stenosis. The sensitivity was 96.0% versus 80.0% and specificity was 84.31% versus 84.31% for API and PPL, respectively. Conclusions PPL and API are useful tools in defining the severity of pure inflow stenosis for mature AVFs in the hands of trained examiners with high sensitivity and specificity.