Off-pump coronary artery bypass and avoidance of hypothermic cardiac arrest improves early left ventricular function in patients with systolic dysfunction

Objective: Off-pump coronary artery bypass surgery (OPCAB) and beating-heart coronary artery bypass grafting (BH-CAB) performed with cardiopulmonary bypass support are used with increasing frequency in the treatment of coronary artery occlusive disease. The utility of OPCAB and BH-CAB in treating high-risk patients has been studied, but the effects of these procedures on ventricular function have not been thoroughly investigated. Methods: Data were collected from a database encompassing all patients who underwent isolated coronary revascularization performed by a single surgeon between August 2002 and March 2007. All procedures (n=507) began as OPCAB operations, but 99 were converted to BH-CAB during surgery. Each patient's ejection fraction (EF) was measured preoperatively and postoperatively (median, 5.0 days after surgery). Results: We found that although the BH-CAB patients tended to be in worse health and to have a lower preoperative EF than the OPCAB patients, both groups of patients had similar improvements in postoperative EF (6.8% vs 5.4%; p=0.65). In addition, multivariable linear regression showed that a lower preoperative EF, age ≥ 70 years, and cardiomegaly predicted less postoperative EF improvement after coronary revascularization by either OPCAB or BH-CAB. Conclusions: Both OPCAB and BH-CAB procedures produce significant and similar short-term improvement in EF in patients with coronary disease. This change in EF may account for the subjective clinical improvements seen early after both procedures.