Beating-Heart Versus Conventional On-Pump Coronary Artery Bypass Grafting: A Meta-Analysis of Clinical Outcomes

Background. Beating-heart on-pump coronary artery bypass grafting (BH-ONCAB) offers a hybrid coronary revascularization technique that may confer the benefits of an "off-pump" operation while maintaining the hemodynamic stability and mechanical support of conventional on-pump CABG (C-ONCAB). This study aimed to identify whether BH-ONCAB confers a morbidity or mortality benefit over C-ONCAB in the immediate and midterm postoperative period. Methods. A systematic literature review identified 13 studies incorporating 3,930 patients (937 BH-ONCAB; 2,993 C-ONCAB) fulfilling our inclusion criteria. Outcomes were meta-analyzed using random-effects modelling. Between-study heterogeneity was investigated through quality assessment, subgroup, and risk of bias analysis. Results. No difference was seen in overall 30-day mortality (13 studies; odds ratio, 0.60; 95% confidence interval, 0.32 to 1.14; p = 0.12), or midterm survival (5 studies; hazard ratio, 0.65; 95% confidence interval, 0.22 to 1.88; p = 0.43) between BH-ONCAB and C-ONCAB. BH-ONCAB was associated with significantly fewer postoperative myocardial infarction events (odds ratio, 0.32; 95% confidence interval, 0.11 to 0.92; p = 0.03); however, no significant difference was observed in other postoperative morbidity outcomes. Intraoperatively, BH-ONCAB resulted in significantly less intraaortic balloon pump use, shorter cardiopulmonary bypass time, and less blood loss. The number of anastomoses and vessels grafted were not significantly different between BH-ONCAB and C-ONCAB. Conclusions. BH-ONCAB is a safe and comparable alternative to C-ONCAB in terms of early mortality and late survival. Furthermore, BH-ONCAB may confer a particular advantage in preventing perioperative myocardial infarction and reducing overall blood loss. Future work should focus on larger matched studies and multicenter randomized controlled trials that risk-stratify patients according to preoperative ventricular function and renal insufficiency to allow us to optimize our surgical revascularization strategy in these high-risk patients. (C) 2015 by The Society of Thoracic Surgeons