Gender differences in outcomes following isolated coronary artery bypass grafting: long-term results

Background: The main purpose of this study was to evaluate the impact of gender on outcomes after isolated coronary artery bypass grafting, in terms of 5-year rates of overall death, cardiac-related death, myocardial infarction, re-hospitalization, repeat percutaneous or surgical revascularization, stroke, new pacemaker implantation, postoperative renal failure, heart failure and need for long-term care. Methods: Two propensity-score matched cohorts, each of 1331 patients, undergoing isolated surgical coronary revascularization at the regional public and private centers of Emilia-Romagna region (Italy) from January 1st 2003 to December 31th 2013, were used to compare long-term outcomes of male (5976 patients) versus female gender (1332 patients). Results: In the matched cohort, males received significantly more bypass grafts (3.0 +/- 1.0 vs 2.8 +/- 1.0, p = 0.001). Left internal mammary artery use and total arterial revascularization were similarly performed in both matched subgroups. Both groups reported similar cumulative rate of all-cause, cardiac-related mortality and stroke at five years. Females experienced significantly higher rate of myocardial infarction, and not significantly higher occurrence of heart failure, and need for long-term care. Males experienced significantly higher rate of cumulative re-hospitalization and higher need for pacemaker implantation. Female gender was not an independent predictor of death at long-term follow-up. Conclusions: Women are more likely to be readmitted with myocardial infarction and congestive heart failure after CABG but experience survival similar to that observed in men. Female gender was not an independent risk factor for mortality. Prevention of new occurrence of postoperative myocardial infarction and enhancement of complete coronary revascularization should be future endpoints.