PREDICTORS OF EARLY AND OVERALL OUTCOME IN CORONARY-ARTERY BYPASS WITHOUT CARDIOPULMONARY BYPASS

Objective: Cardiopulmonary bypass in coronary artery bypass graft oper ations may adversely affect the outcome especially in high-risk patien ts. The purpose of this study is to evaluate results of coronary arter y bypass performed without cardiopulmonary bypass, in a relatively hig h-risk cohort, and to identify predictors of unfavorable outcome. Meth od: Three hundred and thirteen (313) patients, 246 (79%) of whom had h igh-risk conditions, who have a coronary anatomy suitable for coronary artery bypass surgery without cardiopulmonary bypass, underwent this procedure between December 1991 and July 1995. Mean number of grafts/p atient was 1.8 (1-5), and only 71 patients (23%) received a graft to t he circumflex coronary system. Results: Early unfavorable outcome even ts included operative mortality (12 patients, 3.8%), nonfatal perioper ative myocardial infarction (eight patients, 2.6%), emergency reoperat ion (three patients, 0.9%), sternal infection (five patients, 1.6%), a nd nonfatal stroke (two patients, 0.6%). Multivariate analysis reveale d angina pectoris class IV (odds ratio 5.4) and age greater than or eq ual to 70 years (odds ratio 5.0) as independent predictors of early mo rtality. Preoperative risk factors such as repeat coronary artery bypa ss grafting (50 patients, 16%), ejection fraction less than or equal t o 0.35 (85 patients, 27%), acute myocardial infarction (86 patients, 2 8%), cardiogenic shock (ten patients, 3.2%), chronic renal failure (25 patients, 8%), chronic obstructive pulmonary disease (20 patients, 6% ), and peripheral vascular disease (51 patients, 16%) did not increase early mortality. During 33 months of follow-up (range 1-57 months), t here were 42 deaths, at least 16 cardiac-related (one and four years a ctuarial survival of 90% and 76% respectively), and 39 patients (12.5% ) in whom angina returned. Calcified aorta (odds ratio 2.6) and old my ocardial infarction (odds ratio 1.8) were independent predictors of ov erall unfavorable events. Conclusions: Coronary artery bypass grafting without cardiopulmonary bypass can be performed with relatively low o perative mortality in certain high-risk subgroups of patients; however , an increased risk of graft occlusion is a potential disadvantage. Th is procedure should therefore be considered only for patients with sui table coronary anatomy, in whom cardiopulmonary bypass poses a high ri sk. Although the risk of stroke is relatively low, the procedure is st ill hazardous for patients aged 70 years and over. (C) 1997 Elsevier S cience B.V.