Methods: Color flow duplex scanning was used to detect >50 % stenoses in functioning expanded polytetrafluoroethylene grafts. Patients were then subjected to confirmatory angiographic evaluation. Those who had angiographic stenoses >50 % were randomized to balloon angioplasty or observation. Patients were followed-up with duplex scanning every 2 months. Statistical analysis was performed using the Kaplan-Meier technique. Although demographically the patient groups were well matched, there were more prior interventions and concurrent central stenoses in the treatment group. Outcomes were graft thrombosis, graft dysfunction that precluded dialysis, and six or more PTA procedures within 18 months.
Results: In the treatment and observation groups, the 6-month patency rates were 69 % ± 7 % and 70 % ± 7 % , respectively. The 12-month patency rates for the treatment and observation groups were 51 % ± 6 % and 47 % ± 4 % , respectively. There was no significant difference between these two groups ( p = 0.97), with an 80 % confidence limit for detection of a difference greater than 20 % .
Conclusions: This study demonstrates that a generic approach of PTA to treat all polytetrafluoroethylene grafts with stenoses >50 % does not prolong patency and cannot be supported.