An intraoperative diagnosis of dynamic left ventricular outflow tract obstruction using transesophageal echocardiography leads to the treatment with intravenous disopyramide.

Hypertrophic obstructive cardiomyopathy (HOCM) is an uncommon familial disorder, traditionally characterized by asymmetric septal hypertrophy and left ventricular outflow tract (LVOT) obstruction (1). It is now recognized that HOCM may also include those patients with secondary left ventricular hypertrophy (LVH) and dynamic LVOT obstruction. In particular, a syndrome with similar clinical and echocardiographic findings has been identified in elderly patients exhibiting concentric LVH with chronic hypertension, aortic stenosis, or sigmoid-shaped septum (2).

Conclusions: During surgery, dynamic left ventricular outflow obstruction (LVOT) can potentially occur frequently, but diagnosis may be less frequent. When circulatory disturbance occurs with suspicion of LVOT obstruction, transesophageal echocardiography can provide exact proof of diagnosis and basis for immediate treatment.