A Single-Center Experience in Low Ejection Fraction Coronary Artery Bypass Surgery

Abstract

Background. Coronary artery bypass graft (CABG) in patients with an ejection fraction (EF) ≤ 35% predisposes them to higher complications and mortality risks. Given the usually compromised status of other end organs in low EF patients, ONCAB, involving cardiopulmonary bypass (CPB) and aortic cross-clamping, might intuitively pose more complications than OPCAB. Objective. To explore short- and long-term outcomes between ONCAB and OPCAB procedures in patients with EF ≤ 35%. Methods. A retrospective and observational analysis was conducted in 196 patients with EF ≤ 35% who underwent ONCAB (n = 58) or OPCAB (n = 138) procedures at a single center between January 2015 and May 2023. Baseline characteristics were well matched using the stabilized inverse probability treatment weighted matching technique. Results. After matching, ONCAB and OPCAB had comparable 30-day mortality and 30-day cardiac mortality. OPCAB exhibited significantly shorter length of hospital and ICU stays, with a trend towards more discharges to home. Rates of composite complication and its individual components such as acute kidney injury, reoperation bleeding, stroke, pneumonia, GI disease, and atrial fibrillation were similar between the two groups. Rates of sepsis, liver dysfunction, and blood transfusion were significantly lower in the OPCAB group. As assessed by EF and LVDD, neither procedure showed superiority in improving cardiac function. Median follow-up time was 4.9 (interquartile range: 2.1–7.2) years. After matching, long-term overall survival (1, 3, 7 years) and cardiac mortality rates were comparable between OPCAB and ONCAB. Cumulative rates of cardiac arrest, heart failure, myocardial infarction (MI), atrial fibrillation (Afib), renal disease, and readmission (overall and cardiac) at 7 years were similar. Conclusion. This study demonstrates comparable short-term and long-term outcomes between ONCAB and OPCAB in patients with reduced EF, with OPCAB favoring faster recovery. OPCAB appears as a safer and equally effective option for low EF CABG patients. Larger samples and longer follow-ups are needed for conclusive clinical evidence.