Echo-doppler evaluation of mitral incompetence following acute myocardial infarction

ABSTRACT

This study was carried out to reevaluate the prevalence, significance and pathogenesis of mitral regurgitation [MR] following acute myocardial infarction [AMI] utilizing color Doppler imaging technique. This study included 36 patients with acute myocardial infarction. They were classified into two groups group [1] with echo-Doppler evidence of MR and group II with no evidence of MR. Each group was further classified into three subgroups according to the site of infarction anterior [subgroup A], inferior [subgroup B] and combined anterior and inferior infarction [subgroup C]. All patients were subjected to history taking, clinical examination, ECG, chest X-ray and complete echocardiographic examination. The results could be summarized as follows echo-Doppler evidence of MR was found in 50% of the study population. It was commoner among patients with combined infarction [61.3%]. The total CK, mitral annular diameter and left ventricular volumes were significantly increased in patients with compared to those without MR, while FS% and E/A ratio were significantly reduced in patients with MR. The severity of MR was not closely related to the site of infarction, there was significant linear correlation [P < 0.05] between severity of MR and mitral annular diameter while no significant correlation [P > 0.05] was found between severity of MR and total CK. There was a close relationship between the site of infarction and the direction of MR jet. It was concluded that MR is a fairly common finding in patients with AMI. It was common among patient with combined infarction and finally it appears that there are two major causative factors of MR in patients with AMI, asynergy of papillary muscles and/or left ventricular wall and enlargement of the mitral annulus