In-hospital and long-term prognostic value of viable myocardium detected by dobutamine echocardiography early after acute myocardial infarction and its relation to indicators of left ventricular systolic dysfunction

The prognostic value of myocardial viability early after acute myocardial infarction (AMI) is still controversial, depending on the patient under study and the outcome end point considered. Furthermore, the relative prognostic importance of viability compared with indicators of systolic left ventricular (LV) dysfunction is not known. One hundred thirty-eight patients were studied with low-dose dobutamine echocardiography 3 ± 1 days after AMI. Patients were divided in 2 groups based on presence (n = 55) or absence (n = 83) of myocardial viability and followed up for in-hospital and late cardiac events. During hospitalization, myocardial viability was the only independent predictor for recurrent ischemic events (chi-square 5.0, p = 0.025). End-systolic volume index and ejection fraction were both independent predictors of the occurrence of heart failure, whereas gender and end-systolic volume index emerged as independent predictors of hard cardiac events (death and sustained ventricular tachycardia). After hospital discharge, patients were followed for 19 ± 7 months. Again, myocardial viability emerged as the only independent predictor of unstable angina (chi-square 7.7, p = 0.005). Age, hypertension, and ejection fraction were the most important independent predictors of hospitalization for heart failure, whereas ejection fraction was the only independent predictor of hard cardiac events. Presence of myocardial viability early after AMI is the single best predictor of recurrent in-hospital ischemic events and unstable angina after discharge. With respect to hard cardiac events and occurrence of heart failure, indicators of LV systolic dysfunction have a higher prognostic value than presence of myocardial viability.