Prospective comparison of polytetrafluoroethylene and bovine grafts for dialysis

In order to assess the relative merits of polytetrafluoroethylene (PTFE) and bovine heterograft (BG) when used for chronic hemodialysis access, 40 consecutive patients requiring graft fistulas were randomly allocated to receive PTFE ( n = 20) or BG ( n = 20). The two groups were assessed for differences in flow rate, complications, and duration of function. Patency rates were analyzed by the life table method. Mean initial flow rate was similar in the two groups (PTFE = 581 ± 202 ml/min, BG = 643 ± 128 ml/min, P = 0.8). Early (within 30 days) thrombosis occurred in two (10%) grafts from each group. One or more episodes of late thrombosis occurred in eight grafts of each group. Ten of thirteen (77%) late PTFE occlusions and 10 of 14 (71%) late BG occlusions were successfully salvaged by thrombectomy and/or revision. Graft infections occurred with similar frequency in the two groups (two PTFE, three BG), and all necessitated graft excision. Cumulative patency rates at 12 and 24 months were slightly higher in the PTFE group (82 and 67%, respectively) than the rates observed in the BG group (72 and 52%). However, the differences between the two groups are not statistically significant ( P > 0.5) at either interval. This study suggests that PTFE and BG are of comparable efficacy when employed as vascular grafts for dialysis access. Other factors, including lower cost, ease of handling and storage, and ready availability of desired graft sizes may favor use of PTFE for this purpose.