Vascular malformations of the liver in hereditary hemorrhagic telangiectasia may develop high output cardiac failure. Currently, the treatment for refractory hepatic vascular shunts includes hepatic artery embolization. However, hepatic or biliary necrosis may occur if inadequate portal blood flow supplies the liver. In this study, we applied noninvasive portal shunt scintigraphy to determine the portal shunt index for their evaluation. We present a case of the patient with a high PSI value and another case with a normal PSI value (<10%).