Isolated chylopericardium after cardiac operations.

Case histories are reported of four patients having chylopericardium following cardiac operations. This entity can be recognized by noting the presence of postprandial milky mediastinal drainage that stains positive for fat with Sudan III. Chylopericardium is caused by operative injury to the thoracic duct, by operative injury to tributaries of the thoracic duct, or by thrombosis at the confluence of the left subclavian and jugular veins with subsequent obstruction of thoracic duct drainage. Appropriate management, which may be either conservative or operative, depends upon the volume and duration of drainage. The conservative approach entails adequate pericardial drainage and institution of a medium-chain triglyceride diet; operative therapy entails ligation of the thoracic duct low in the posterior mediastinum.