Congenital portosystemic shunts: diagnosis and treatment.

Congenital portosystemic shunts (CPSS) are rare vascular malformations that create an abnormal connection between portal and systemic veins resulting in complete or partial diversion of the portal flow away from the liver to the systemic venous system. Different anatomic types exist and several classifications have been proposed. They can be associated with other malformations especially cardiac and heterotaxia. The main complications include hepatic encephalopathy, liver tumors, portopulmonary hypertension, and pulmonary arteriovenous shunts. Diagnosis relies on imaging, and prenatal diagnosis is possible. Spontaneous closure of the CPSS is possible in some anatomic forms during the first year of life. When the CPSS remains patent, radiologic or surgical closure of the CPSS may prevent, resolve, or stabilize complications. Interventional radiology plays a key role for both the preoperative evaluation with occlusion test to assess the exact anatomy and to measure portal pressure after occlusion of the CPSS. Endovascular closure is the first option for treatment when possible.