We studied 108 patients who sustained an acute myocardial infarction (AMI) by means of echocardiography, pulsed doppler (PD) and Doppler color flow imaging (CD). We evaluate the presence of mitral regurgitation (MR) and it relationship to the site of the AMI and also to the ventricular function. The incidence of MR was 50.92%, (55/108), it was detected in higher percentage when the AMI was inferior (61.8%) than when anterior (39.6%). The correlation with the ejection fraction (EF) was only significative when the AMI was anterior. The incidence of MR was 57.1% when the EF was below 25%. CD had better diagnostic capabilities independently of the site of the AMI, (48% vs 32.1% when the AMI was anterior and 76.1% vs 52.6% when it was inferior).