PORTOSYSTEMIC SHUNT: PATHOPHYSIOLOGY, DIAGNOSIS AND TREATMENT

Abstract

Portosystemic shunts (PSS) are vascular anomalies that allow blood to be redirected from the portal vein to the systemic circulation, bypassing the liver and resulting in liver dysfunction and systemic clinical manifestations, such as hepatic encephalopathy (HE). These shunts can be congenital, more common in small dogs, or acquired, usually in older dogs with chronic liver disease. Initial diagnosis is made through clinical screening and laboratory tests, with confirmation by imaging tests such as computed tomography (CT) and Doppler ultrasound. Clinical treatment aims to stabilize the patient, control clinical signs, and prepare for surgery. Surgical correction, often performed with an ameroid ring, promotes gradual occlusion of the anomalous vessel, preventing acute portal hypertension. Postoperative follow-up, including laboratory tests and ultrasound, is crucial to monitor the effectiveness of the occlusion and prevent complications. With early diagnosis and appropriate treatment, the long-term prognosis is favorable in most cases.