Outcomes and costs of coronary artery bypass grafting: comparison between octogenarians and septuagenarians at a tertiary care centre.

backgroundDecision-making related to coronary artery bypass grafting (CABG) in elderly patients is hampered by inadequate outcome data. We compared the clinical outcomes of octogenarians with those of septuagenarians who underwent CABG. Our secondary objective was to compare the costs associated with CABG in these groups.

methodsWe conducted a retrospective database review of patients 70 years of age and older who had undergone CABG at a regional cardiac surgical centre in Hamilton, Ont., between July 1, 1997, and Apr. 30, 2000. A total of 1034 patients were divided into 3 age groups: young septuagenarians (aged 70-74 years), old septuagenarians (aged 75-79) and those 80 and older. Costs were determined in a subset of 773 patients with the use of a case-costing system for cardiac surgery developed at our institution.

resultsThe 3 groups were similar with respect to sex distribution and preoperative risk factors. Urgency scores at referral differed significantly between the groups, with the young septuagenarians demonstrating the lowest risk (mean score [and standard deviation] 4.48 [1.3] in that group, 4.28 [1.4] in the old septuagenarian group and 4.11 [1.2] in the octogenarian group). The rates of all complications combined were similar between the 3 groups (27.1%, 28.1% and 29.6% in the young and old septuagenarian groups and the octogenarian group respectively). There were no significant differences between the 3 groups in the mean number of grafts per patient (3.0, 3.1 and 3.0 respectively), the rate of postoperative death (3.3%, 5.7% and 4.2%), the mean length of stay (11.7, 13.4 and 12.6 days) or the incidence of postoperative myocardial infarction (4.5%, 3.4% and 4.2%). The total cost of CABG per patient did not differ significantly between the 3 groups.

interpretationGiven that patients who are accepted for CABG represent a selected population, our findings suggest that, with careful triage, CABG in octogenarians is as safe as, and no more costly than, CABG in septuagenarians.