Backgrounds: The left atrial volume (LAV) is a powerful predictor of mortality after acute myocardial infarction (AMI). We investigated factors affecting LA remodeling and the relation between the change of the LAV and adverse events after AMI. Methods: In 245 patients (mean age 60 짹 11 years, 63% men) with AMI undergoing successful percutaneous coronary intervention, transthoracic echocardiography were performed during admission and after 14 months (mean 14 짹 9 months). We analyzed the clinical outcomes (composite of cardiac death, hospitalization for heart failure and myocardial infarction). Results: All subjects were followed up for 33 짹 13 months. After adjustment for clinical and echocardiographic parameters, moderate to severe mitral regurgitation at baseline, peak troponin I level during admission and changes in left ventricular (LV) end-diastolic volume and LV ejection fraction (EF) were independently associated with changes in LAV (Table). In Cox���s proportional hazard model, independent predictors of clinical outcomes were the change of LAV (hazard ratio [HR] 1.073, 95% confidence interval[CI] 1.033-1.115), Age >65 years (HR 1.048, 95% CI 1.016-1.081), Heart failure (HR 3.178, 95% CI 1.475-6.848), LV mass index (HR 1.012, 95% CI 1.005-1.020) and changes in EF (HR 0.969, 95% CI 0.941-0.999). Conclusions: The change of LAV after AMI is an independent predictor of clinical outcomes and is related to the degree of initial mitral regurgitation and changes of left ventricular systolic function during follow-up period. Key words: change of LA volume, AMI, predictor