Coronary artery bypass grafting in patients over 70 years old: The influence of age and surgical technique on early and mid-term clinical outcomes

Objective: To investigate the influence of age and modern techniques of coronary artery bypass grafting with or without cardiopulmonary bypass on early and mid-term mortality and morbidity in a consecutive series of elderly patients. Methods: From April 1996 to December 2000, data of 3842 patients undergoing coronary revascularisation were prospectively entered into a database. Data were extracted for 990 patients older than 70 years: (A) 70-74 years, (n=659); (B) 75 or more years, (n=331). Results: A total of 990 elderly patients (≥70 years) underwent coronary revascularisation, 219 (22.1%) with off-pump surgery. Elderly patients were more likely to have higher CCS, NYHA and EuroScores, history of previous MI, unstable angina, renal dysfunction, left main stem disease ≥50%, and to be urgent. However, they were less likely to be overweight. In-hospital mortality, occurrence of re-intubation, renal dysfunction, and hospital stay were significantly higher in this elderly group. Overall, the distribution of mortality was doubled in the female gender although this was not statistically significant. Patients undergoing on-pump surgery had lower EuroScore, were less likely to be >75 years of age, likely to have obesity or hypercholesterolaemia, or to have suffered a previous cerebro-vascular accident. However, they had more extensive coronary disease, were more likely to have unstable angina, and received more grafts than those undergoing off-pump surgery. After adjustment for prognostic variables, off-pump surgery was found to be associated with reduced inotropic use, intra-operative arrhythmias, blood loss and transfusion requirement when compared to on-pump coronary surgery (point estimates of odd ratios, 0.26-0.87) (all P<0.05). Mid-term mortality or cardiac-related events were similar in the two groups. Conclusions: Early but not mid-term mortality is higher in patients aged 75 or more years when compared with those aged 70-74 years. Off-pump coronary artery bypass surgery is safe and effective in the elderly population.