Impact of early coronary artery bypass graft in an unselected acute coronary syndrome patient population.

BACKGROUND: Performance of coronary artery bypass graft (CABG) during an acute coronary syndrome (ACS) is mainly used in high-risk patients. Although potentially life-saving, patients undergoing early CABG are traditionally associated with a worse outcome than those not requiring CABG. Is this really true in an unselected ACS population? The aim of this study was to evaluate, in an ACS population, if the performance of CABG during the index hospitalization influences in-hospital outcome.

METHODS AND RESULTS: Retrospective analysis of a nationwide database of 12,988 ACS patients admitted since 2002. Of those, 267 patients underwent CABG during the index hospitalization (group A) and 12,721 did not (group B). Group B patients were further divided in 2 subgroups: those submitted to percutaneous coronary interventions (PCI) (group B1; n=3948) during the index hospitalization and those not submitted to mechanical revascularization (group B2; n =8773). Patients from group A more frequently had diabetes, hypercholesterolemia, hypertension, and previous angina; they were also more often on cardiovascular medication before admission. Patients that underwent CABG were more often in Killip class IV at admission (4.8% versus 1.4% versus 2.0%); they also received more nitrates and catecholamines. Left ventricular function was better in group B1. Group A patients were more often on mechanical ventilation and intra-aortic pump and they had more in-hospital complications (31.1% versus 18.7% versus 17.3%), namely recurrent angina, re-infarction, and mechanical complications. They had a more severe coronary anatomy and the culprit lesion was more frequently on the left main (7.7% versus 0.5% versus 2.2%). However, their in-hospital mortality was significantly lower (1.1% versus 2.2% versus 6.8%; P<0.001). Multivariate analysis showed that performance of early CABG was an independent predictor of lower mortality (odds ratio of 0.12), as were the use of low-molecular-weight heparins, beta-blockers, and angiotensin-converting enzyme inhibitors.

CONCLUSIONS: In unselected patients admitted for ACS, performance of early CABG, despite being performed in higher-risk patients, is associated with very low in-hospital mortality, even when compared with the mortality of lower-risk population not submitted to early CABG. Therefore, early performance of this procedure should be considered more often in eligible patients.