Patent ductus arteriosus in an infant with atrioventricular septal defect and pulmonary hypertension: diagnosis by transesophageal color flow echocardiography.

An infant with complete atrioventricular septal defect (atrioventricular canal) was examined by standard transthoracic two-dimensional pulsed Doppler and color Doppler echocardiography. No evidence of ductus arteriosus was present. Preoperative transesophageal echocardiography identified a patent ductus: the left-to-right shunt seen by color Doppler echocardiography was enhanced by pharmacologic maneuvers aimed at decreasing pulmonary vascular resistance and increasing systemic vascular resistance. Transesophageal echocardiography was found to be more sensitive than transthoracic echocardiography even in a small infant.