Risk factors of in-hospital mortality for isolated on-pump coronary artery bypass graft surgery in the northeast of Iran from 2007 to 2016

Background and objectiveCoronary artery bypass graft (CABG) surgery is the most common cardiac surgery worldwide. The reported mortality rates for this operation vary greatly. We aimed to determine the risk factors of in-hospital mortality for isolated on-pump CABG surgery.MethodsThis was a large-scale retrospective cohort study of two heart centers in Golestan province. Patients over the age of 18 from both genders who underwent isolated on-pump CABG procedures from 2007 to 2016 were included. The study outcome was in-hospital mortality, which was determined according to the clinical records of study patients.ResultsA total of 3704 patients were included in the study, and 63% were men. In-hospital mortality occurred in 2.8% (n=103) of the patients. The median (IQR) age of survived and not-survived patients were 59 (53-65) and 62 (55-75) years, respectively. 44% of the mortalities occurred in patients older than 65, while 28% of the survivors were older than 65. Multivariable logistic regression indicated that emergency CABG (OR 4.52, 95% CI, 1.45, 14.02; P = 0.009) and cardiopulmonary bypass time (CPB) (OR 1.004, 95% CI 1.001, 1.008; P = 0.034) were the risk factors of in-hospital mortality. The area under the receiver operating characteristic (ROC) curve (AUC) of the model consisting of operative and preoperative variables was 0.70 (acceptable performance).ConclusionOur study revealed an acceptable mortality proportion for CABG surgeries conducted in the region. Emergency CABG and CPB time were the main risk factors for in-hospital mortality after CABG.

Automated summary

This large-scale retrospective cohort study aimed to determine the risk factors for in-hospital mortality after isolated on-pump coronary artery bypass graft (CABG) surgery. The study included 3704 patients and found that emergency CABG and cardiopulmonary bypass time were the main risk factors for in-hospital mortality.