Occurrence of an intrahepatic porto-arterial shunt after hepatic artery embolization with Gelfoam powder in rats and rabbits.

Postmortem perfusion studies were carried out following hepatic artery embolization (HAE) with Gelfoam powder in rats (n = 17) and rabbits (n = 10). The inflow of barium particles into the hepatic arteries after portal vein injection (porto-arterial shunt: P-A shunt) was analyzed by stereomicroscopic and histologic examinations. A P-A shunt was observed in 12 of 17 rats (71%) following HAE (embolization group). The difference in occurrence rates of P-A shunt between control (1/12 = 9.2%) and embolization groups was statistically significant (chi 2, p less than 0.01) in rats. In rabbits, a P-A shunt was seen in only one of 10 animals in the embolization group. P-A shunting may have an important role in reconstructing the blood supply to hepatic tumors after HAE, and administration of anticancer drugs via the portal vein following HAE might be effective. However, the differences among different species of animals should be considered before clinical application.