Arterial and portal blood supply in cirrhosis: a functional evaluation

The uptake of (125)I albumin microaggregates (U-(125)I-AMA) from portal blood, during a single passage through the hepatic reticuloendothelial system, has been found to be generally decreased in cirrhosis. To investigate if a similar phenomenon occurs for the colloid flowing through the hepatic artery, the U-(125)I-AMA was first calculated in normal dogs after injection of a mixture of (51)Cr red blood cells ((51)Cr-RBC) and (125)I-AMA into the hepatic artery by comparing hepatic indicator dilution curves (IDC) obtained with both indicators. In nine dogs, the U-(125)I-AMA from hepatic artery blood was generally over 90%, as previously reported for the same colloid flowing through the portal vein in another group of normal dogs. This approach was then applied in nine patients with alcoholic cirrhosis who underwent combined umbilicoportal vein, hepatic vein, and hepatic artery catheterisation because of severe portal hypertension. Hepatic indicator dilution curves were obtained in the nine patients after injection of a mixture of (51)Cr-RBC and (125)I-AMA into the portal vein and the hepatic artery. The U-(125)I-AMA from portal and hepatic artery blood was measured by comparing (51)Cr-RBC and (125)I-AMA hepatic IDC. U-(125)I-AMA varied between 5.2 and 90.5% after portal vein injection and between 13.7 and 90.1% after hepatic artery injection; not difference was found between paired values. In all patients the extraction of indocyanine green (E-ICG) was calculated during a continuous infusion and significant correlations were found between E-ICG and U-(125)I-AMA from portal blood (r=0.931; p <0.001) or from hepatic artery blood (r=0.861; p <0.005). The decreased uptakes can be related to intrahepatic shunts or sinusoidal changes responsible for ineffective phagocytosis and restricted access of dye to parenchymal cells. These data indicate that in cirrhosis the hepatic artery and portal vein blood is cleared of colloid and ICG in a similar fashion and suggest nearly identical blood supply to the regenerative nodules by the hepatic artery and portal vein. Thus U-(125)I-AMA from hepatic artery or portal vein blood, as well as the E-ICG, may be used to estimate the functional hepatic blood supply in cirrhosis; this may prove to be useful in the prognosis of patients before portacaval shunts.