Background

Chylopericardium is an accumulation of lymph in the pericardial sac and a rare condition in dogs. To this date, there are only a few reported cases of chylopericardium in dogs. One case of chylopericardium was considered idiopathic and resolved after thoracic duct ligation and/or pericardiectomy. Other described causes were embolized mesothelial cells in a tracheobronchial lymph node, a right atrium rhabdomyoma and thymoma. Chylothorax on the other hand has been reported in a bullmastiff with tricuspid valve dysplasia and atrial septum defect. The pathogenesis in our case might be explained by increased permeability in the lymphatic vessels associated with elevated pressure in the thoracic duct (right-sided heart failure due to the tricuspid valve stenosis) combined with communication between the thoracic duct and pericardial lymphatics, as seen in sheep and human cases.

Case Presentation

A 2-year-old, 33-kg female castrated Labrador Retriever was referred for exercise intolerance, hyporexia and abdominal distention. Point-of-care-ultrasound revealed ascites, hepatic congestion, severe pericardial effusion and cardiac tamponade. Pericardiocentesis was performed and the chylus nature of the fluid was confirmed by cytology, triglyceride and cholesterol measurement. Repeated pericardiocentesis was necessary within 24 hours after admission, after which a pericardial stay-catheter was placed. Cardiac ultrasound revealed severe tricuspid valve stenosis. Balloon dilatation of the stenotic valve was performed, resulting in a significant drop in the mean diastolic trans-valvular Doppler gradient and long-term resolution of the chylopericardium. No other cause for the pericardial effusion could be identified, suggesting that this is the first described case of chylopericardium due to tricuspid valve stenosis. Approximately 14 months after balloon valvuloplasty, the owner reported a normal quality of life.

New/Unique Information

To the author’s knowledge, this is the first described report of chylopericardium associated with tricuspid valve stenosis. Balloon valvuloplasty of the stenotic valve resulted in long-term resolution of the chylopericardium.

In our case, a pericardial stay-catheter was placed due to rapid reoccurrence of pericardial effusion after repeated pericardiocentesis. The pericardial catheter remained in situ for 4 days without any complications. This suggests that medium long-term pericardial catheters could be a safe option for in-hospital patient management.

E-mail: niels.groesser@anicura.nl