[Specificity of systolic anterior motion of the mitral valve in the echocardiographic diagnosis of hypertrophic cardiomyopathy (author's transl)].

In order to determine the prevalence of sistolic anterior motion (SAM) of the mitral valve, we evaluated the echocardiographic records of 229 consecutive patients with a variety of cardiovascular conditions. SAM was present in all the 9 patients of this series with hypetrophic cardiomyopathy and in additional 4 patients with other conditions. Their diagnosis were: arterio-venous fistula of the forearm, tetralogy of Fallot, Prinzmetal angina and idiopatic hypercynetic cardio-circulatory state. Thus SAM without hypertrophic cardiomyopathy is not a rare event in patients undergoing echocardiography. The wide variability of conditions associated with SAM suggests that it represents a functional and aspecific abnormality and does not involve peculiar anatomic factors.