Background and objectives: Left ventricular (LV) remodeling after acute myocardial infarction (MI) is strongly related to infarct size. The contribution of viability in the infarct zone and the presence of multivessel disease remains unknown. Because dobutamine stress echocardiography (DSE) can estimate infarct size and detect myocardial viability and multivessel disease, we postulated that DSE can accurately predict LV remodeling after acute MI.
Methods: To test this hypothesis, 30 patients age 59 +/- 15 years, 21 men, 14 with anterior MI, underwent multistage DSE (low dose, 5 to 10 microg, and peak dose) during the first week after MI occurred. Follow-up echocardiography was performed at >/=1 year. LV remodeling (2 SD increase in LV volume) occurred in 17 of 30 patients. Remodeling occurred in 12 (92%) of 13 patients with large nonviable infarct and in 1 (13%) of 8 patients with large viable infarct (P <.001). Univariate predictors of LV remodeling were baseline ejection infarct (P <.01), infarct size (number of akinetic segments at low dose P <.01), age (P <.05), and multivessel coronary disease (P <. 01). The only multivariate predictor of remodeling was infarct size. Viability of infarct zone was a negative predictor of LV remodeling.
Conclusion: DSE performed during the first week after acute MI predicts subsequent LV remodeling. Infarct size, nonviability of the infarct zone, and age are independent predictors of LV remodeling. Myocardial viability is a strong negative predictor of LV remodeling.