Optimal coronary artery bypass grafting strategy for acute coronary syndrome

Abstract

Objective: Conventional coronary artery bypass grafting (CABG) using cardiopulmonary bypass and cardiac arrest is associated with higher mortality and morbidity rates in acute coronary syndrome (ACS) patients undergoing surgery. Although off-pump CABG (OPCAB) is beneficial for high-risk patients, its efficacy for ACS is unknown, with on-pump beating CABG an adjunctive method. We investigated the effects of OPCAB and on-pump beating CABG for ACS.

Methods: We evaluated 121 consecutive patients with ACS (91 males, 30 females; mean age 69.5 ± 10.3 years) who underwent CABG since 2000. Seventy-five had unstable angina (UA) and 46 acute myocardial infarction (AMI) [non-ST elevation (NSTEMI): 22, ST elevation (STEMI): 24]. We assessed CABG for acute coronary syndrome under our primary OPCAB strategy, and compared perioperative status between UA and AMI patients.

Results: (1) Sixty-five (87 %) with UA underwent OPCAB, 8 on-pump beating CABG, and 2 conventional CABG. Conversion from OPCAB was seen in 4 patients. In-hospital mortality was 1.3 %. (2) All UA patients who had intra-aortic balloon pumping (IABP) underwent OPCAB. No patients with preoperative IABP experienced conversion from OPCAB. (3) In AMI patients, hospital mortality was higher (8.9 %) and the ratios for OPCAB, on-pump beating CABG, and conventional CABG were 39, 57, and 4 %, respectively. Mortality was exclusively seen in patients with STEMI who underwent conventional CABG.

Conclusions: OPCAB might have beneficial effects for ACS patients with UA, while IABP was found essential for completing OPCAB. In AMI patients, on-pump beating CABG might be reasonable for avoiding conversion from OPCAB and ischemic perfusion injury.