Survival of prosthetic grafts of different materials after impairment of a native arteriovenous fistula in hemodialysis patients.

In our department, hemodialysis vascular accesses with graft, are used in patients with impairment of native distal and proximal arteriovenous fistulas (AVF-E). The aim of this study was to compare the survival of grafts of different materials (PTFE vs. bovine vein) in these patients. From 1991 to 1999, we prospectively evaluated 53 patients (35 women, 18 men, age 68 +/- 11 years, on dialysis for 70 +/- 65 months). Fifty-three PTFE, 10 reinforced PTFE, and 22 bovine vein grafts were placed. We evaluated the primary patency (PP) (days between fistula placement and the last dialysis before thrombosis occurred) and the secondary patency (SP) (days between fistula placement and the last dialysis treatment before it was considered lost) by separating PTFE survival from that of bovine veins. In the same patients, we also evaluated the survival of the native arteriovenous fistulas (AVF-E) during the pregraft period. Furthermore, we evaluated 404 patients (172 women, 232 men, age 65 +/- 14 years, on dialysis for 50 +/- 53 months) in whom only AVF-E were placed during the same follow-up period. Graft and AVF-E survival were calculated according to the Kaplan-Meier method. In patients with grafts, the PP at 1 year was 17.4% for PTFE and 23.9% for bovine veins. At 12 months, the SP of bovine veins was significantly higher than that of PTFE (81,9% vs. 50%, p < 0.04). In the patients who only had AVF-E, the PP and SP was, respectively, 43% at 12 months and 52.4% at 50 months. A preliminary experience in 22 patients with a 20 month follow-up confirms better survival of bovine veins than PTFE (p < 0.04).