[Compressive pericardial effusion after heart surgery in the adult.  Contribution of bidimensional echocardiographic findings]. 
In series of 1450 consecutive cardiopulmonary bypasses for cardiac surgery in adults, we observed 20 cases of post-operative compressive pericardial effusion.  The effusion occurred some time after the thoracic drains were removed and had to be evacuated.  Two-dimensional echocardiography proved essential to the diagnosis : it easily detected the lesion even when clinical symptoms were misleading but above all, it demonstrated, in our series, that the classical post-operative "tamponade" is a specific entity consecutive to posterior, circumscribed, small volume effusions which mainly compress the left cardiac cavities.