Access Survival amongst Hemodialysis Patients Referred for Preventive Angiography and Percutaneous Transluminal Angioplasty

Summary Background and objectives Referring hemodialysis patients for elective access angiography and percutaneous transluminal angioplasty (PTA) is commonly done to prevent access failure, yet the effectiveness of this procedure remains unclear. Design, setting, participants, & measures An observational matched cohort analysis among 40,132 Medicare beneficiaries receiving hemodialysis with a fistula or graft was performed. Cox regression was used to determine whether access intervention was associated with improved 1-year access survival. Results Nonsurgical access intervention was found to be frequent at a rate of 20.9 procedures per 100 access years. In the 1-year period after intervention using angiography and PTA, the overall access failure rate was 53.7 per 100 access years in the intervention group and 49.6 in the nonintervention group (HR 1.02; 95% CI, 0.96 to 1.08). Similar findings were also seen when the analysis was repeated in only fistulas (HR 1.06; 95% CI, 0.98 to 1.15) and grafts (HR 0.95; 95% CI, 0.86 to 1.05). In patients with a low intraaccess flow rate (HR 0.86; 95% CI, 0.75 to 0.99) or a new access (HR 0.79; 95% CI, 0.71 to 0.89), angiography and PTA significantly increased access survival when compared with nonintervention (P for interaction was 0.0001). Angiography-PTA-related upper-extremity hematoma, vessel injury, or embolismthrombosis occurred in 1.1% of all patients. Conclusions Access characteristics significantly modify the survival benefits of angiography and PTA intervention where the benefits of these interventions are most seen in newer accesses or accesses with insufficient flow. Clin J Am Soc Nephrol 6: 2669–2680, 2011. doi: 10.2215/CJN.02860311