[Congenital absence of the left pericardium. Case report and review of the literature].

Congenital absence of the pericardium, whether partial or total, is a rare abnormality. If suspicion of such a malformation arises it should be classified because of possible herniation of the atrium or ventricle. The authors report the case of an asymptomatic young male patient in whom the diagnosis was suggested radiographically, electrocardiographically (total electrical alternans has been noticed) and confirmed by cross-sectional echocardiography, computed tomography and magnetic resonance imaging. Only in exceptional cases should it be necessary to perform an exploratory thoracotomy. In patients with complete pericardial defects no specific therapy is indicated, however, in patients with partial defects surgical treatment is indicated. Congenital pericardial defects are not completely benign, as has been suggested before.