SUMMARY
Hepatic arteriovenous fistulas are vascular communications between a hepatic artery and a portal vein causing the blood to bypass the hepatic sinusoid network and return by retrograde flow to the portal system. This rare occurrence can be congenital or acquired, and can lead to anorexia, weight loss, diarrhea, neurological and ascites, and has portosystemic deviation as the main diagnosis. The clinical treatment is palliative, requiring surgery to definitively resolve the disease. The present report reports a case of arteriovenous fistula in dogs, from the beginning of the clinical signs, the diagnosis and exclusively clinical treatment carried out, having a survival approximately 19 months.