Survival analysis of octogenarian patients with coronary artery disease managed by elective coronary artery bypass surgery versus conventional medical treatment.
Academic Article
Overview
abstract
BACKGROUND: In view of the increasing age of the U.S. population, the use of coronary artery bypass surgery in the management of the elderly patients with coronary artery disease needs to be better defined. METHODS AND RESULTS: To evaluate the effects of medical and surgical therapy on octogenarian patients with coronary artery disease in our institution, we retrospectively reviewed 177 consecutive octogenarians who underwent cardiac catheterization over a 5-year period. Sixty-five of these patients were found to have significant coronary artery disease without severe valvular disease. Elective coronary artery bypass surgery was performed in 36 patients, whereas 29 patients were continued on maximization of medical therapy and not referred to the surgical service. Left ventricular ejection fractions (LVEF) were similar for the two groups, whereas the surgical patients had slightly higher average number of diseased coronary vessels and slightly higher levels of angina. Univariate survival analysis of 20 variables, including the choice of medical versus surgical treatment and the associated conditions, was performed by Mantel-Cox testing of the paired Kaplan-Meier product limit survival curves stratified by the subgroups of each variable. The variables found to be significant were then included in a multivariate survival analysis using the Cox proportional hazards regression model. The treatment choice, LVEF, level of angina, and presence of any aortic and/or mitral valvular disease at the time of cardiac catheterization were found to be independent prognostic indicators of survival in the follow-up period of 26 +/- 16 months. The 3-year probability of survival rates for the surgical patients and medical patients were 77.4% and 55.2%, respectively (p = 0.0294). The New York Heart Association functional class of the surgical group decreased significantly from a mean preoperative level of 3.4 +/- 0.5 to a mean level of 1.2 +/- 0.6 at the follow-up interview (p < 0.01), whereas it did not significantly change for the medical group from a baseline mean level of 2.8 +/- 1.3 to a mean follow-up level of 2.5 +/- 1.0. CONCLUSIONS: We conclude that coronary artery bypass surgery provided improved long-term survival and functional benefit compared with conventional medical treatment in a small group of octogenarian patients in our institution.
