FACTORS INFLUENCING 1-YEAR PATENCY OF CORONARY-ARTERY SAPHENOUS-VEIN GRAFTS

Background. To evaluate the possible influence of a series of clinical angiographic and surgical variables on the 1-year patency of saphenou s vein (SV) coronary graft, data collected prospectively in a multicen ter randomized clinical trial were analyzed. Methods and Results. The study group included 349 patients - 847 SV distal anastomoses - who un derwent angiography at a median time of 374 days after surgery. By log istic binomial regression analysis, age, sex, smoking habits, hyperten sion, high cholesterol, previous myocardial infarction, and angina wer e not found to be significant factors leading to graft occlusion. Amon g the angiographic and surgical variables, the following were retained as predictive of higher occlusion risk; (1) vessel diameter (less-tha n-or-equal-to 1.5 mm versus > 1.5 mm, odds ratio (OR) =2.46); (2) the location of the grafted vessel, namely, the right coronary artery vers us the left anterior descending (OR=2.15); and (3) the wall motion of the vessel-dependent myocardial region (altered versus normal: OR=2.12 ). The presence of two or three risk factors multiplied the occlusion risk up to 11-fold. Conclusions. The study suggests that vessel diamet er, wall motion of the vessel-dependent myocardial region, and locatio n of the grafted vessel are the main determinants of SV coronary graft patency during the first postoperative year. Knowledge of these arter y-specific factors may provide a basis for estimating the risk of graf t occlusion, thereby modifying surgical strategy and postoperative sur veillance.