Hepatic Lesions Associated with Intrahepatic Arterioportal Fistulae in Dogs

Abstract

Seven cases of hepatic arterioportal fistulae in young dogs (mean age 6 months) are described. All cases were presumed to be congenital in origin. The onset of clinical signs, which frequently included gastrointestinal and neurological disturbances, was usually sudden. All dogs had clinical evidence of portal hypertension in the form of ascites, and all developed multiple extrahepatic portacaval venous shunts consequential to portal hypertension. The neurological disturbances were likely the result of portacaval shunting. The arterial and venous vessels involved in the fistulae had markedly altered wall structure. Hepatic regions adjacent to the fistulae frequently evidenced marked bile duct proliferation. Hepatic parenchymal atrophy, relative collapse of distributing portal veins, dilatation of hepatic arterial branches and proliferation of hepatic arterioles were seen throughout the liver; these changes closely resembled those present with portacaval shunting in the absence of hepatic arterioportal fistulae. The importance of recognizing that hepatic arterioportal fistulae and multiple extrahepatic portacaval shunts usually coexist and separately influence the morphological appearance of the liver is stressed.

Congenital Hepatic Arteriovenous Fistula with Intrahepatic Portosystemic Shunt and Aortic Stenosis in a Dog

“…Preoperatively, right ventricular enlargement and diuretic drug reactivity ascites in the present case may be results of vicarious high-output heart failure. Hepatic lobectomy is recommended as surgical treatment for hepatic arteriovenous fistula with a single hepatic lobe lesion [6,8,12]. However, hepatic artery ramal ligation technique was chosen in the present case because the lesion extended to multiple lobes [7,12].…”

“…66(3): 299-302, 2004 Hepatic arteriovenous fistula is a condition characterized by a communication between the portal or the hepatic vein and hepatic artery. All previous case reports of dogs regarding this condition showed vascular abnormality with communication between the portal and hepatic artery [1,3,6,7,9,13]. Dogs with hepatic arteriovenous fistula usually exhibit ascites and secondary multiple portosystemic shunt (PSS) due to portal hypertension [8,12].…”

Les fistules artério-veineuses hépatiques chez le chien : diagnostic, traitement, pronostic

“…Ils apparaissent en moyenne vers l'âge de 6 et 9 mois (WHITTING et al, 1986 ;EASLEY et CARPENTER, 1975), bien que certains cas aient été décrits chez des animaux adultes jusqu'à un âge de 3 ans (CHANOIT et al, 2005). Il n'est pas noté pour cette affection de prédisposition raciale ou sexuelle.…”

“…Une hypoplasie hépatocellulaire est également observée, elle est due à la mauvaise perfusion portale. Enfin une hyperplasie des canalicules biliaires est également rencontrée (MOORE et WHITTING, 1986). …”

“…De plus, ces animaux doivent être, pour l'im-COMMUNICATIONS mense majorité d'entre eux, nourris de façon particulière pour le reste de leur vie (régime hypoprotéique). Ces mesures sont en relation directe avec le fait que même si les symptômes s'estompent, il est reconnu que la fonction hépatique, objectivée par scintigraphie (WHITTING et al 1986) ou par tests biochimiques (CHANOIT et al, 2005;WHITTING et al, 1986), ne revient jamais à la normale.…”