Chylopericardium Fig. 4. Neck sonography showing 1.9 cm sized multilo- cular, compressible cystic lesion between the sternoclei- domastoid muscle and the internal jugular vein of the left neck. were within the normal range. Repeated pericar- diocentesis was performed, and an immediate gushing out of 700 mL of a milky-yellowish fluid ensued (Fig. 3). An examination of the pericardial fluid showed pH 6.8, protein 7.0 g/dL, glucose 98 mg/dL, LDH 560 IU/L, cholesterol 97 mg/dL, and triglyceride 1078 mg/dL. RBCs and WBCs were uncountable due to cell clumping. The adenosine deaminase level was 17.0 U/L and the CEA level 1.15 ng/mL. Routine cultures for bacteria and tuberculosis were subsequently reported as nega- tive and a cytologic examination showed no tumor cells. These findings with inappropriately elevated triglyceride in the pericardial fluid suf- ficed to diagnose chylopericardium. The patient underwent extensive investigations to determine the secondary causes. Chest computed tomo- graphy revealed a suspicious small cystic lesion on the left neck and mediastinal haziness. The possibility of cystic hygroma with mediastinal extension was highly suggested by radiologists. Neck sonography also showed a 1.9 cm sized multilocular, compressible cystic lesion between the sternocleidomastoid muscle and the internal jugular vein of the left neck. These findings were compatible with cystic hygroma (Fig. 4). The cystic lesion could not be aspirated due to patient's refusal. To demonstrate the presence of any anomalous communication between the lym- phatic channels and the pericardial sac, we per- formed a direct lymphangiography. However, no Fig. 5. Six months follow-up chest X-ray showing nearly normal size of heart. direct communication between the pericardial sac and the thoracic duct could be definitely estab- lished. Follow-up echocardiography was per- formed 10 days after the pericardiocentesis and showed a massive reaccumulation of pericardial effusion. 11 days after pericardiocentesis, the patient underwent pericardiostomy. Using the subxyphoid approach, a pericardial window was made with 32 Fr draining tube insertion in an attempt to prevent pericardial fluid reaccumula- tion and cardiac tamponade. Incision of the pericardium resulted in the extrusion of 600 mL or more of milky fluid. The pericardial fluid analysis showed that it had the same nature as the previous sample. When the patient was placed on total parenteral nutrition for 30 days and a subse- quent low fat diet enriched with medium-chain triglycerides for 15 days, the drainage reduced to 30-40 mL per day. On the 45th day after pericar- diostomy, drainage tube was removed and she was discharged from the hospital on a low fat diet. She remained totally asymptomatic without interval changes of heart size on chest X-ray (Fig. 5) or clinical signs of cardiac tamponade at the 6 month follow-up. DISCUSSION Groves and Effler,8 in 1954, reported a case of chylopericardium in a 31-year-old woman who was found to have an isolated recurrent accumu- Yonsei Med J Vol. 46, No. 3, 2005