Analysis of the Clinical Factors Affecting Graft Patency Rate after Infrainguinal Arterial Reconstruction

ABSTRACT

PURPOSE: This study was designed to determine the clinical factors affecting the long-term graft patency of leg arterial bypass for the patients with chronic lower limb arterial occlusion. METHOD: The clinical data of 81 femoro-distal bypasses performed at Yeungnam University Hospital from January 1996 to December 2002 were included for this retrospective study. A Log-Rank test of Kaplan-Meier method and Cox proportional hazard analysis were performed to identify those main effects that were predictive of graft patency. The patients, 79 males and 2 females, ranged from 37 to 81 years of age, with a mean age of 64. The highest incidence occurred among those in their 60s and 70s. Associated diseases were hypertension in 42 cases (51.8%), diabetes mellitus in 15 (18.8%), cardiac disease in 26 (32.1%) and cerebrovascular disease in 6 (7.4%). A history of smoking was noted in 76.5% of the cases. As for the clinical grades of chronic limb ischemia according to SVS/ISCVS classification, 21 limbs (25.9%) were classified as grade I (category 3), 40 (49.4%) as grade II, and 20 (24.7%) as grade III. The site of distal anastomosis was above the knee popliteal artery in 53 limbs (65.4%), below the knee popliteal artery in 8 (9.9%) and tibial artery in 20 (24.7%). As bypass conduit, autologous vein graft was used in 67 limbs (82.7%) and polytetrafluoroethylene (PTFE) graft in 14 (17.3%). There were no hospital mortalities or major perioperative complications. RESULT: From the univariate analysis of 21 clinical variables (age, sex, smoking, hypertension, diabetes mellitus, coronary arterial disease, congestive heart failure, chronic pulmonary disease, cerebrovascular disease, malignancy, hypercholesterolemia, clinical grade of chronic limb ischemia by SVS/ISCVS, level of occlusion, preoperative ankle-brachial index, type of graft, site of distal anastomosis, operation time, status of inflow artery, postoperative ankle-brachial index, clinical outcome criteria by SVS/ISCVS, postoperative anticoagulation therapy), 5 factors were identified as being associated with long-term graft patency preoperative clinical grade (P=0.03), preoperative ankle-brachial index (P=0.00), level of occlusion (P=0.03), type of graft (P=0.00) and clinical outcome criteria (P=0.00). In multivariate analysis, type of graft, PTFE graft (vs. autologous vein graft, P=0.002), and clinical outcome criteria, minimally improved (vs. moderately, and markedly improved, P=0.029), showed a lower graft patency rate. CONCLUSION: These results suggest that autogenous vein is more acceptable for leg arterial bypass and poor early clinical outcome predicts poor long term graft patency rate.