Early and Late Mortality of Patients Undergoing Aortic Valve Replacement After Previous Coronary Artery Bypass Graft Surgery

Abstract

In a small number of patients who undergo coronary artery bypass graft surgery (CABG), a hemodynamically significant aortic valve lesion requiring aortic valve replacement (AVR) develops as they grow older. In a limited number of studies in small patient groups, high mortality has been shown in patients undergoing AVR after CABG. We undertook this study to determine the mortality risk factors for patients who undergo AVR after CABG procedures. The outcome of 104 patients treated at our institution between January 1983 and December 1993 was retrospectively reviewed. The initial surgery was CABG in all patients. The patient population included 86 men (83%) and 18 women (17%); their mean age was 67 years. Overall, 70% of patients had congestive heart failure, and 96% had multivessel coronary artery disease. The diagnosis was aortic stenosis in 68% of patients, aortic insufficiency in 16%, and combined aortic stenosis and aortic insufficiency in 16%. Postoperative complications included worsening congestive heart failure (35%), perioperative myocardial infarction (13%), and bleeding (28%). The early mortality was 14%, and the late mortality was 17% (mean follow-up, 35 months). The risk factors for early mortality were number of diseased vessels (P = .028), renal failure (0.000), and prior myocardial infarction (P = .028). A perioperative predictor of early mortality was cardiopulmonary bypass time (P = .000). The risk factors for late mortality included preoperative diabetes mellitus (P = .007), postoperative acute respiratory distress syndrome (P = .011), and ventricular arrhythmias (P = .0001). The survival at 1, 5, and 10 years was 96%, 75%, and 49%, respectively. Risk factors were identified for early and late mortality in patients undergoing AVR after previous CABG. Although early morbidity and mortality were high, the longterm outcome of the survivors was favorable.