Arterioportal fistulas: introduction of a novel classification with therapeutic implications.

Arterioportal fistulas (APFs) are arteriovenous communications between the splanchnic arteries and the portal vein that represent an infrequent cause of presinusoidal portal hypertension. They can be acquired or congenital. Penetrating hepatic trauma, including liver biopsies, represent the most common etiology. They can be asymptomatic or manifest with portal hypertension. An abdominal bruit is a valuable physical finding. Persistence of an APF can cause hepatoportal sclerosis and possibly portal fibrosis. A detailed radiologic evaluation is mandatory. One must differentiate between small peripheral intrahepatic APFs (type 1) and large central APFs (type 2). The former usually resolve spontaneously, whereas the latter can cause portal hypertension and hepatic parenchymal changes. Type 1 APFs caused by needle injury can be followed by Doppler ultrasound. All other fistulas need treatment. Arterioportal fistulas are first treated by transcatheter embolization. Surgical approaches are reserved for complex cases. Congenital APFs (type 3) are diffuse and intrahepatic and can be difficult to manage. Overall, the prognosis is good. Herein, we propose a novel classification for arterioportal fistulas with therapeutic implications.