[Hemitruncus arteriosus in an asymptomatic young man--diagnostic value of transesophageal echocardiography]

The aortic origin of one pulmonary artery, also called hemitruncus arteriosus, is a rare congenital anomaly with poor prognosis. In this report the case of an asymptomatic 18-year-old man with a systolic precordial murmur and the electrocardiographic finding of biventricular hypertrophy is described. The diagnosis of hemitruncus was confirmed by cardiac catheterization. Echocardiography showed biventricular hypertrophy and moderate enlargement of the right atrium and ventricle. In contrast to reports in children, the diagnosis could not be verified by transthoracic echocardiography because of the lack of a satisfactory acoustic window. On the other hand, the aortic origin of the right pulmonary artery and the continuation of the main pulmonary artery as left pulmonary artery were visualized by transesophageal echocardiography. However, the shunt-volume could not be determined by means of the velocity-time-integral and the diameter of the right pulmonary artery because of the turbulent blood-flow in its proximal part.