Dynamic intraventricular obstruction in acute myocardial infarction

Transient left ventricular dynamic obstruction (TLVO) is an infrequent comp lication in acute myocardial infarction (AMI). Its hallmark is a new systol ic murmur associated with hemodynamic worsening. An echocardiogram is neces sary for diagnosis. We report on two cases, both of which had a good outcom e. Serial echocardiograms showed that enhanced contractility of the basal l eft ventricular segments obstructed cardiac ejection by means of mitral val ue systolic anterior movement in the left ventricular outflow tract. In bot h cases, the intraventricular gradient remained for several days and subseq uently disappeared. The understanding of this mechanism is useful for manag ement of this clinical problem.