Trends in coronary artery bypass surgery: Impact on early outcomes

Background: improvements in nonsurgical revascularization have left a group of higher-risk patients presenting for operation in a later stage of coronary artery disease. We undertook this study to analyze temporal changes in demographic and clinical profiles and outcomes of cardiac surgical patients. Methods: we identified and retrieved preoperative, intraoperative, and postoperative variables for 3064 consecutive patients who underwent myocardial revascularization at the Aga Khan University Hospital between 2006 and 2011. Mortality and morbidity outcomes were compared using univariate and multivariate analyses. Results: mean age, prevalence of left ventricular systolic dysfunction, unstable angina, mean number of occluded vessels, and arrhythmias at presentation increased steadily over time. The prevalence of diabetes, chronic lung disease, peripheral vascular disease, prior stroke, prior myocardial infarction, and left main disease declined. Operative mortality did not change significantly (3.5% vs. 3.8%, p = 0.512). Determinants of operative mortality included older age, female sex, renal insufficiency, left ventricular systolic dysfunction, and longer bypass and crossclamp times. Conclusion: coronary operations are increasingly performed in higher-risk patients with greater comorbidities. Despite this, operative mortality has not increased.