Anteroapical stunning and left ventricular outflow tract obstruction

Dynamic left ventricular outflow tract (LVOT) obstruction is typically observed in the setting of hypertrophic cardiomyopathy. It has also been reported with concentric LV hypertrophy, excessive sympathetic stimulation, and acute myocardial infarction. We describe 3 patients with chest discomfort after emotional stress, who had pronounced abnormalities on electrocardiograms, insignificant obstructive coronary disease and hemodynamic instability with LVOT obstruction, and regional wall motion abnormalities. Suppression of contractility with beta-blockers resulted in resolution of the gradient and in clinical improvement. On follow-up, functional recovery was excellent, and ventricular function had normalized. The conditions and mechanisms that may produce this sequence of events are discussed. The most probable scenario is that an acute ischemic insult secondary to vasospasm, LV stunning, and acute geometric remodeling produced a substrate for LVOT obstruction that was exacerbated by basal LV hypercontractility. The importance of this observation is that routine treatment of cardiogenic shock cannot be used and that conservative management results in excellent prognosis.