Coronary artery bypass grafting in acute myocardial infarction: analysis of predictors of in-hospital mortality

Objective: Coronary artery bypass grafting (CABG) during the acute phase of infarction (AMI) is associated with increased operative risk. The aim of this study was to determine predictors of in-hospital mortality in patients undergoing CABG in AMI. Methods: During three years, all patients undergoing CABG in AMI were retrospectively analyzed of the institutional database. Sixty variables per patient were evaluated: 49 preoperative variables from the 2000 Bernstein-Parsonnet and EuroSCORE models, 4 preoperative variables not considered in these models (time between AMI and CABG, maximum CKMB, Troponin maximum and ST-segment elevation) and 7 intraoperative variables [(cardiopulmonary bypass (CPB), CPB time, type of cardioplegia, endarterectomy, number of grafts, use of internal thoracic artery and complete revascularization]. Univariate and multivariate analysis for the outcome of in-hospital mortality were performed. Results: The mean time between AMI and CABG was 3.8 +/- 3 days. The overall mortality was 19%. In the multivariate analysis: age > 65 years OR [16.5 (CI 1.8 to 152), P=0.013]; CPB > 108 minutes [OR 40 (CI 2.7 to 578), P=0.007], creatinine > 2 mg/dl [OR 35.5 (CI 1.7 to 740), P=0.021] and systolic pulmonary pressure > 60 mmHg [OR 31 (CI 1.6 to 591), P=0.022] were predictors of in-hospital mortality. Conclusion: Conventional preoperative variables such as age > 65 years, creatinine > 2 mg/dl and systolic pulmonary pressure > 60 mmHg were predictive of in-hospital mortality in patients underwent CABG in AMI.