Imaging Diagnosis of Multiple Congenital and Acquired Vascular Anomalies in a Young Bulldog

A nine-month-old female entire Bulldog presented with a two week history of vomiting, small intestinal diarrhoea and progressive abdominal distension. On physical examination the dog was depressed, of thin body condition and a fluid thrill was evident on abdominal palpation. Biochemistry revealed low urea (2.1mmol/l, range 2.5-7.4), moderate hypoalbuminaemia (16g/l, range 23-45), mildly increased alanine aminotransferase (345IU/l, range 13-88) and markedly increased fasting bile acids (109.5μmol/l, range 0-10). Abdominal ultrasound findings included moderate ascites and multiple arteriovenous fistulae in the presumed right lateral liver lobe and acquired portosystemic shunting vessels in the left cranial abdomen. Analysis of the abdominal effusion was consistent with a pure transudate.

Computed tomographic angiography (CTA) was performed to further assess the vascular anatomy. Numerous tortuous arteries around the entrance of the porta hepatis, involving the caudate and right medial lobes, as well as a larger shunting vessel were visualized connecting the portal vein with the hepatic artery. The hepatic artery arose from a combined coeliac and cranial mesenteric artery. Additionally multiple acquired portosystemic shunts were visualized entering a markedly enlarged left renal vein.

Based on the CTA findings the AV fistula was considered unresectable. The dog
was treated for ascites with spironolactone and for hepatic encephalopathy with metronidazole, lactulose and dietary management. The ascites resolved and the dog’s body weight and mentation improved. Euthanasia was required ten months later due to progression of clinical signs.

Arteriovenous fistulas are a rare hepatic vascular anomaly. The ascites and acquired portosystemic shunts were attributed secondary to portal hypertension. Given the patients young age most likely this was a congenital condition. […]