On-pump beating heart versus conventional coronary artery bypass grafting: comparative study on early and long-term clinical outcomes

Abstract

We reviewed our experience with on-pump beating (OPB) heart coronary artery bypass grafting (CABG) to evaluate the impacts of obviating aortic cross-clamping and cardioplegic arrest on clinical outcomes compared with conventional CABG (C-CABG). Between 2006 and 2012, elective isolated cardiopulmonary bypass (CPB)-assisted CABG was consecutively performed in 645 patients (mean patient age 63.3±9.1 years, 471 women) with 254 (39.4%) undergoing OPB-CABG and 391 (60.6%) undergoing C-CABG. The early and long-term clinical outcomes were compared between the two groups after adjusting for risk profiles through propensity score (PS) analyses. The OPB-CABG group presented significant morbidities more frequently than the C-CABG group, including severe chronic kidney disease (CKD) (P=0.026), severe chest pain (P<0.001), and poor left ventricular function (P<0.001). Early mortality occurred in 6 (2.4%) and 2 (0.5%) patients in the OPB- and C-CABG group, respectively (P=0.087). The number of distal anastomosis was comparable between the two groups (3.0±0.9 vs. 3.0±1.0, P=0.816). After PS matching, the incidence of major complications such as stroke (P>0.99) and new-onset dialysis (P=0.109) was comparable. During a median follow-up of 81.0 months (quartiles 1-3, 66.6-95.0 months), 118 patients died and the PS-matched models showed no significant between-group differences in the risk of overall death [hazard ratio (HR), 1.19; 95% confidence interval (CI), 0.72-1.95; P=0.507] and major adverse cardiac events (MACE) (HR, 1.49; 95% CI, 0.67-3.31; P=0.328). The OPB strategy may be as safe and effective as the conventional strategy during CABG among patients with similar risk profiles. A prospective randomized trial is warranted to better ascertain the beneficial impact of OPB-CABG as both a viable and a durable alternative strategy to C-CABG.