Intra-aortic balloon pump associated with dynamic left ventricular outflow tract obstruction after valve replacement for aortic stenosis.

An unstable patient with critical aortic stenosis had an intra-aortic balloon pump placed preoperatively for hemodynamic support and alleviation of symptoms. After separation from cardiopulmonary bypass following aortic valve replacement, the patient was hypotensive with increased pulmonary artery pressures. Transesophageal echocardiography revealed left ventricular outflow tract obstruction associated with systolic anterior motion of the mitral valve and severe mitral regurgitation. This pathophysiology was present when ventricular systole was preceded by balloon counterpulsation, but was absent during unassisted systole. This case report demonstrates a potentially significant untoward effect of intra-aortic balloon pump augmentation after aortic valve replacement for aortic stenosis. The timely diagnosis of this iatrogenic condition in the operating room permitted the prompt implementation of appropriate management strategies and avoided unnecessary surgical intervention.