Congenital absence of the pericardium: echocardiography as a diagnostic tool.

Between 1982 and 1992, 10 patients who underwent echocardiography at the Mayo Clinic were found to have congenital absence of the pericardium. Clinical, electrocardiographic, chest roentgenographic, echocardiographic, computed tomographic, and magnetic resonance imaging features were reviewed in this patient group. The characteristic features of this entity are reviewed. The echocardiographic features in order of frequency are (1) unusual echocardiographic windows, seen in all 10 patients, (2) cardiac hypermobility in nine patients, (3) abnormal ventricular septal motion in eight patients, and (4) abnormal swinging motion of the heart in seven patients.