Chylopericardium is a rare disease that may result from a variety of causes, such as cardiac surgery, trauma, obstruction of the thoracic duct near its drainage into the subclavian vein, or have no identifiable underlying cause. The present report describes a case of idiopathic chylopericardium in which percutaneous transabdominal occlusion of the thoracic duct was performed as an alternative to surgical duct ligation. The procedure was successful, resulting in a decrease in pericardial fluid accumulation. However, it failed to cure the patient, as constrictive pericarditis developed 2 months later, requiring surgical pericardectomy. Whether this could have been avoided by early (percutaneous) pericardial fenestration is unknown.