Factors associated with patency following angioplasty of hemodialysis fistulae.

Patency after percutaneous transluminal angioplasty of native hemodialysis arteriovenous fistulae (AVFs) is highly variable. This study aimed to identify predictors of patency following angioplasty in native AVFs. All endovascular procedures performed in native AVFs between 2005 and 2013 at two institutions were retrospectively reviewed. Clinical, anatomic, biochemical, and medication variables were subjected to univariate and multivariate Cox regression analysis to identify predictors of postintervention primary and secondary patency. During the study period, 207 patients underwent first angioplasty of their AVF. Follow-up ranged from 14 days to 8 years, during which another 247 endovascular interventions were performed to maintain patency. Postintervention primary patency rates at 6, 12, and 24 months were 66%, 49%, and 29%, respectively. Postintervention secondary patency rates at 6, 12, and 24 months were 94%, 84%, and 79%, respectively. On multivariate adjusted Cox regression analysis, upper-arm AVFs (P = .00072), AVFs less than 6 months of age (P = .0014), presence of multiple stenoses (P = .019), and degree of initial stenosis (P = .016) were significantly associated with shorter postintervention primary patency. A previously failed AVF was the only significant predictor of postintervention secondary patency loss (P = .0053). Anatomic factors related to the AVF location, AVF age, and the extent of the lesion are important predictors of restenosis after balloon angioplasty. Traditional cardiovascular risk factors, metabolic and inflammatory markers, and medications were not associated with postintervention patency.