Influence of hormone replacement therapy on graft patency after femoropopliteal bypass grafting

Objective: Thromboembolic events are more frequent in women with establishe d cardiovascular disease who are receiving hormone replacement therapy (HRT ). The effect of HRT on the outcome of women undergoing infrainguinal bypas s grafting is unknown. The purpose of this study was to estimate the influe nce of risk factors, in particular HRT, on the outcome of women undergoing femoropopliteal bypass grafting. Methods: During a 5-year period (between 1993 and 1998), 131 femoropoplitea l bypass graft procedures were performed in 106 women. The criteria prepare d by the Ad Hoc Committee on Reporting Standards (Society for Vascular Surg ery/North American Chapter of the International Society for Cardiovascular Surgery) were followed. Both univariate (Kaplan-Meier method) and multivari ate analyses (Cox proportional hazards model) were used to determine the as sociation among preoperative variables, graft patency, limb salvage, and su rvival. Results: The average age of the patients was 66.4 years; 26% of the patient s were receiving HRT. Indications for femoropopliteal bypass grafting were limb salvage (80%) and disabling claudication (20%). Autogenous vein was us ed in 48% of procedures, polytetrafluoroethylene (PTFE) in 49%, and PTFE-ve in composite grafts in 3%. Distal popliteal anastomosis was above the knee in 52% and below the knee in 48%. Overall primary patency rate was 81% at 1 year, 65% at 3 years, and 56% at 5 years. Primary patency rates at 1, 3, a nd 5 years were 75%, 45%, and 23%, respectively, for HRT users and 84%, 72% , and 65%, respectively, for nonusers of HRT. Overall, cumulative 1- and 5- year limb salvage results were 96% and 92%, respectively, and long-term sur vival at 1, 3, and 5 years was 96%, 86% and 74%, respectively. With univari ate and Cox regression analyses, HRT was identified as the only independent predictor of reduced primary graft patency (Kaplan-Meier method, log-rank test, P = .004; relative risk, 2.5; 95% CI, 1.3-4.8). Women receiving HRT w ho underwent a procedure with PTFE had the lowest primary graft patency rat es (relative risk, 3.4; 95% CI, 1.5-7.8; P = .006). Conclusions: Women undergoing femoropopliteal bypass graft procedures who a re receiving HRT have significantly reduced primary graft patency rates. Th e risk of graft failure increases when prosthetic materials are used.