Reduction of Left Ventricular Dilation Beyond the First Year After Anterior Myocardial Infarction

ABSTRACT Background Reduction of left ventricular (LV) dilation (RD) beyond the first year after ST-segment–elevation myocardial infarction (STEMI) is unknown. We investigated its potential occurrence in comparison with stationary (SD) and progressive (PD) dilation. Methods and Results Perfusion gated SPECT features at 1 and 3 years were evaluated in 168 3-year survivors of a first anterior STEMI. Comparisons were made among patients with RD (≥15% reduction of LV end-systolic volume [LVESV]), SD ( 51 mL; P P  = .002) and was associated with increased ejection fraction ( P values .008 and .009, respectively). In the 3 groups, however, LVESV changes were unrelated to 1-year LV volumes, ejection fraction, or contractility score. Conclusions At 3 years following anterior STEMI there is reduction of LV dilation in about 21% of patients associated with increases in ejection fraction in those with or without clearly dilated ventricles at 1year. These findings add to the complexity of LV remodeling and possibly suggest very late changes in infarct size.