[Intrapericardial congenital ectasias of the left atrium].

Congenital intrapericardial dilatation of the left atrium is an abnormality which is either very rare (16 cases reported in the literature) or one that is easily missed. The clinical features are unhelpful, and the diagnosis is suggested by the outline on X ray and confirmed by angiocardiography. The great importance of this abnormality lies in its natural history. Disorders of rythm (9 cases out of 16) and embolism (5 cases out of 16) are amongst the complications to be weighed up when deciding the treatment policy. Operative treatment, which is straightforward, seems to us to be indicated in all cases.