Decreasing mortality for coronary artery bypass surgery in octogenarians

Background — Octogenarians are the fastest growing population in Canada and have also been referred for coronary artery bypass grafting (CABG) with increasing frequency during the past decade.

Objective To examine the changing trends in preoperative risk profiles, postoperative outcomes and hospital resource use in the octogenarian population.

Methods — A retrospective review was conducted to identify all patients 80 years of age or older who underwent isolated CABG at the Toronto General Hospital (Toronto, Ontario) between 1990 and June 2005. To examine the effect of time on preoperative risk, patients were divided into three groups based on year of operation: 1990 to 1994, n=92; 1995 to 1999, n=202; and 2000 to June 2005, n=314.

Results — The preoperative risk profile of octogenarians undergoing CABG has changed over the years. The percentage of patients with diabetes, dyslipidemia, hypertension and left main disease increased over time (P<0.05). However, the requirement for urgent/emergent operations decreased. In-hospital mortality declined from 7.1% (1990 to 1999) to 3.2% (2000 to June 2005, P=0.02). The prevalence of low cardiac output syndrome, intra-aortic balloon pump insertion and stroke decreased over time. Preoperative myocardial infarction (OR 4, P=0.0004), left main disease (OR 3.7, P=0.0013) and year of operation (1990 to 1994 [OR 3.3, P=0.03]; 1995 to 1999 [OR 2.9, P=0.02]) independently predicted in-hospital mortality. Hospital resource use in terms of hours on ventilator, length of stay in the intensive care unit and postoperative length of stay decreased over time (P<0.0001).

Conclusion — Despite a changing risk profile, hospital outcomes of octogenarians were improved over time with a reduction in hospital resource use. The results suggest that CABG can and should be performed in this expanding population.