Coronary artery bypass grafting in acute myocardial infarction. Analysis of preoperative predictors of mortality.

OBJECTIVE

To assess preoperative predictors of mortality in patients undergoing coronary artery bypass grafting (CABG) within the first 30 days of acute myocardial infarction (AMI).

METHODS

Between March 1998 and July 2002, 753 AMI patients were consecutively and prospectively entered into a database, 135 (17.9%) of whom underwent isolated CABG and were enrolled in this study. The following prognostic factors were assessed by multivariate analysis: age, gender, diabetes, history of previous AMI, CABG or coronary angioplasty (PTCA), anterior infarct location, Q-wave AMI, the use of fibrinolytics, elapsed time from AMI to the procedure, and presence of complications in the preoperative period.

RESULTS

Overall in-hospital mortality was 6.7%, ranging from 12.5% in patients with preoperative complications to 1.4% in those with no complications. Only history of previous angioplasty (p = 0.037) and cardiogenic shock (p = 0.002) showed a statistically significant correlation with postoperative mortality. The use of thrombolytics, on the other hand, in the initial management of AMI showed a negative correlation with mortality (p = 0.035).

CONCLUSION

CABG in the acute phase of MI is associated with distinct operative mortality, depending on the patients preoperative clinical condition. Among those factors analyzed, preoperative cardiogenic shock and history of previous angioplasty were predictive of worse prognosis in this group of patients.