Mitral regurgitation following first-time acute myocardial infarction--early and late findings by Doppler echocardiography.

A total of 61 patients with first-time mild to moderate acute myocardial infarction and no reinfarction within the following 2 months were studied prospectively by Doppler echocardiography before hospital discharge and after 2 months to evaluate the prevalence of mitral regurgitation. Twenty-one age-matched healthy subjects served as controls. At baseline, the prevalence of Doppler-recorded mitral regurgitation was 74% and 29% in patients and controls, respectively. In the patients, the regurgitant flow measured by color flow Doppler was 1.04 cm2 (range 0.2-8 cm2) and occupied 7.5% (range 2-45%) of the left atrial area. Corresponding figures for controls were 0.35 cm2 (0.1-0.6) and 2.4% (0.7-4.5), respectively. On continuous wave Doppler, most patients (33/45) had Doppler signals similar to those of healthy controls. The prevalence of mitral regurgitation was about the same in anterior and inferior infarction (75 and 72% respectively). In the patients, the prevalence was similar after 2 months (79%) with minor changes in the Doppler characteristics of the regurgitation (regurgitant flow 1.12 cm2 and occupying 8.1% of left atrial area). The study demonstrates that in a group of patients with first-time mild to moderate myocardial infarction the prevalence of Doppler-recorded mitral regurgitation is high and mild in severity in the majority of the cases. The changes remain almost similar even after 2 months.