A reappraisal of the factors affecting early patency of aortocoronary saphenous vein bypass grafts. Current experience with extensive revascularization employing sequential grafting techniques.
A number of factors potentially influencing the patency rates of aortocoronary bypass grafts were investigated in a consecutive series of 50 patients by control angiography at 28 +/- 26 days and by univariate and multivariate analysis of a selected set of clinical, surgical and angiographic predictors. There were 234 anastomoses in this series, a mean of 4.7 per patient (range 1 to 9), 215 of which were connected to sequential vein grafts. After surgery, 40 patients were treated with anticoagulants and/or platelet inhibitors. Of the 234 coronary anastomoses studied, 219 were patent (93.6%). Coronary artery diameter, patient's age and previous myocardial infarction were shown to be independent predictors of increased risk of anastomotic occlusion. Arteries less than 1.5 mm in diameter had a patency rate of 84.9%, versus 96.1% for vessels 1.5 mm or larger (p = 0.009). The use of side-to-side anastomoses with sequential grafts seemed to counterbalance the unfavourable effect of small arterial size. Patients aged 65 or older had a lower probability of having all their grafts patent than younger patients did (50 vs 89%, p = 0.01). Patients with previous myocardial infarction similarly had a lower probability of having all their grafts patent compared to patients without previous infarction (68 vs 95%, p less than 0.05); this correlation was explained by a more frequent occlusion rate of grafts directed to fibrotic left ventricular areas. The effect of anticoagulants and of platelet-inhibitors was favourable, but did not reach statistical significance.(ABSTRACT TRUNCATED AT 250 WORDS)
D000368:Aged; D000704:Analysis of Variance; D017023:Coronary Angiography; D001026:Coronary Artery Bypass; D005260:Female; D006083:Graft Occlusion, Vascular / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged