Results of Isolated Emergency Coronary Bypass Surgery According to Acute Coronary Syndrome

Abstract

Introduction: The aim of the present study was to evaluate the results of isolated emergency coronary artery bypass grafting (CABG) according to acute coronary syndrome (ACS) types in a single center with 5-year experience. Patients and Methods: A total of 138 patients who underwent emergency isolated CABG surgery from September 2009 to July 2014 in our hospital were enrolled in this retrospective descriptive study. The cohort was divided into four groups according to the type of ACS: (1) unstable angina (USAP) (n= 14, 10.1%), (2) nonST segment elevated myocardial infarction (NSTEMI) (n= 43, 31.2%), (3) ST segment elevated myocardial infarction (STEMI) (n= 65, 47.1%), and (4) cardiogenic shock (SHOCK) (n= 16, 11.6%). There were three coprimary outcomes in the study: (1) in-hospital and 30-day mortality rate results, (2) mortality analysis according to subgroups, and (3) to assess the performance of European System for Cardiac Operative Risk Evaluation (EuroScore) II in patients with ACS who underwent emergency isolated CABG. Results: No significant differences were observed between the groups with regard to demographic and preoperative risk factors. The observed 30-day total mortality rate was 15.9% (n= 22). Mortality rates in the subgroups were 7% (n= 1) in USAP, 4.65% (n= 2) in NSTEMI, 15.38% (n= 10) in STEMI, and 68.75% (n= 11) in SHOCK, respectively. There was a significant difference in mortality between the groups (p< 0.05). The receiver operating characteristic curve value of EuroScore II was 0.890 (95% Confidence Interval, 0.826-0.937). Conclusion: The current study demonstrates that the observed mortality rate for STEMI and SHOCK patients requiring emergency CABG remains high. Moreover, EuroScore II has a good risk prediction in NSTEMI patients while significantly underestimates the mortality in the other groups.