REOPERATIVE CORONARY-ARTERY BYPASS PROCEDURES - RISK-FACTORS FOR EARLY MORTALITY AND LATE SURVIVAL

Objectives: The number of coronary artery disease reoperations is incr easing. The aim of this paper is to identify risk factors and evaluate the results of REDO coronary artery bypass grafting (CABG). Material: Between January 1984 and October 1994, 594 patients underwent REDO-CA BG and 3157 underwent primary-CABG. The mean age was 62 years with 84% men. Hypertension, hyperlipidemia, insulin dependent diabetes, smokin g and renal insufficiency were all more frequent in the REDO-group. A significantly higher number of patients undergoing REDO-CABG were in t he Canadian Cardiovascular Society (CCS) angina class 3 and 4, had ins table angina, had left main stem stenosis of greater than 70% and 3-ve ssel disease compared to those undergoing primary-CABG. The mean preop erative left ventricular function (LVEF) was 49.8 (REDO) vs. 58.2%, wi th a P value of less than 0.001. Results: The overall postoperative mo rtality rate for REDO-operations was 9.6 (57/594) vs. 2.8% for primary -CABG. Patients with a reoperative interval of more than 1 year had an 8.9% mortality rate, compared to those reoperated less than 1 year af ter the initial CABG, where the mortality was 21% with a P value of le ss than 0.05. Postoperative low cardiac output syndrome, intraaortic b alloon pump support, prolonged ventilatory support (> 24 h), hemorrhag e and gastrointestinal complications were prominent features of the RE DO-group (all P < 0.01). Urgent operation, CCS class 3 and 4, LVEF of less than 40%, generalized arteriosclerotic disease and advanced age ( > 80 years) were independent risk factors for postoperative death in b oth groups. Preoperative renal insufficiency, diabetes and short inter val from primary-CABG were added risk factors in the REDO-group. The 5 -years survival rate after REDO-CABG was 89%, while the cardiac event- free survival rate was 79% and at 7 years 84 and 62%, respectively. Co nclusions: Reoperative CABG is effective, but has an increased operati ve mortality and morbidity. The long-term results are encouraging. Uns table angina, poor preoperative left ventricular function, renal insuf ficiency, insulin dependant diabetes and an interval shorter than 1 ye ar of the initial operation were independent riskfactors for mortality . Copyright (C) 1997 Elsevier Science B.V.