The increasing safety of cardiac surgery has led to the frequentreferral of octogenarians for operation. Between 1980 and 1989, we reviewedour experience with 103 octogenarians (59 male, 44 female; mean age 82years) to determine the surgical risk factors and outcome in the elderlypopulation. There were 71 coronary bypasses (CABG), 11 aortic valvereplacements (AVR), 11 AVR-CABG, 4 mitral valve replacements (MVR), 3MVR-CABG and 3 AVR-MVR-CABG. Seventeen patients died during hospitalization(16.5%) including 9 CABG (13%); 1 AVR (9%), 2 AVR-CABG (18%), 2 MVR (50%),1 MVR-CABG (33%) and 2 AVR-MVR-CABG (67%). Statistical analysis of 22perioperative variables suggested that a preoperative intraaortic balloon,a history of congestive heart failure, mitral valve replacement, urgentoperation, need for preoperative inotropic support and the number ofanastomoses performed were significant or marginally significant (P lessthan 0.15) univariate predictors of operative mortality. Multivariateanalysis revealed that the need for a preoperative intraaortic balloon (F =13.1), history of congestive heart failure (F = 6.8), and MVR (F = 6.7)were significant (P less than 0.001) independent predictors of mortality.Postoperative complications included arrhythmias in 36 patients (35%),respiratory insufficiency in 11 (11%), reversible neurological deficit in15 (14%), and a permanent neurological deficit in 6 patients (6%).Actuarial survival was 90% and 82% at 1 and 2 years, respectively. Seven of86 (8%) long term survivors sustained a stroke in the follow-up interval.The mean follow-up of survivors was 23 +/- 19 months with a meanimprovement in NYHA class of 1.4 (P less than 0.001).(ABSTRACT TRUNCATED AT250 WORDS)