Management and outcome of a dog with hepatic arteriovenous malformation and extensive thrombosis of splanchnic vessels

Abstract This report describes the diagnosis, treatment and long‐term follow‐up of a dog with hepatic arteriovenous malformation and extensive thrombus of the splanchnic vessels. A 1‐year‐old, male, neutered golden retriever presented with haematochezia and ascites. The abdominal effusion was consistent with transudate, and initial diagnostic work‐up, including bloodwork and abdominal ultrasound, was overall unremarkable. A thoracic and abdominal computed tomography scan revealed a hepatic arteriovenous malformation affecting the left lateral, left medial and quadrate liver lobes, and extensive thrombosis of multiple splanchnic vessels. A heparin infusion was initiated. Surgical resection of the abnormal liver lobes was pursued. Histopathology of the liver was consistent with arterioportal malformation and atrophy of hepatic parenchyma. New portal vein thrombi were noted post‐operatively. The dog was prescribed rivaroxaban, clopidogrel and gastroprotectants. All thrombi were resolved by 5 weeks post‐operatively. Long‐term follow‐up (28 months) revealed persistent hepatic insufficiency requiring long‐term medical management.