Prophylactic intra-aortic balloon counterpulsation before surgical myocardial revascularization in patients with acute myocardial infarction

Abstract

Introduction: Prophylactic intra-aortic balloon counterpulsation (pIABC) is recommended for high-risk patients undergoing coronary artery bypass grafting (CABG) surgery. Criteria for high-risk patients benefiting from pIABC are unclear. This study aimed to specifically describe the effect of pIABC on outcomes of patients with acute myocardial infarction (AMI) undergoing CABG. Methods: In 178 of 484 AMI patients (non-ST-segment elevation myocardial infarction [NSTEMI] or ST-segment elevation myocardial infarction [STEMI] ≤5 days before surgery) without cardiogenic shock who underwent CABG between 2008 and 2013, pIABC was initiated preoperatively. After propensity score matching, the outcomes of 400 patients were analyzed (pIABC: 150; Control: 250). Results: After propensity score matching, baseline and operative characteristics were balanced between the groups except for a higher rate of patients with a left ventricular ejection fraction (LVEF)≤30% in the pIABC group (26% vs. Control: 13%; p=0.032). Seven point two percent (7.2%) of the control patients received an IABP intraoperatively or postoperatively. Postoperative extracorporeal life support (ECLS) was only needed in the control group (1.2% vs. 0%; p=0.01). Postoperative plasma curves of troponin I, creatine kinase (CK) and creatine kinase isoform MB (CK-MB) levels were reduced in the pIABC group compared with the control group. In-hospital mortality was reduced in the pIABC group (3.3% vs. control: 6.4%; p=0.18). After multivariate adjustment for other preoperative risk factors, pIABC was significantly protective concerning in-hospital mortality (HR 0.56; 95%-CI 0.023-0.74; p=0.021). Mortality (pIABC vs. control) was more affected in patients with preoperative LVEF≤30% (2/36 (5.6%) vs. 6/31 (19%); heart rate (HR) 0.25; 95%-CI 0.046-1.3; p=0.13) compared with LVEF>30% (3/114 (2.6%) vs. 10/219 (4.6%); HR 0.56; 95%-CI 0.15-2.1; p=0.55). Long-term survival did not differ between the groups. Conclusions: pIABC in CABG for AMI is associated with reduced perioperative cardiac injury and in-hospital mortality. Long-term survival is not affected.