Surgical Treatment of Portosystemic Shunts Using an Ameroid Constrictor in Four Dogs

Abstract

For congenital extrahepatic portosystemic shunts (PSS) have been treated with surgical ligation of the primary shunting vessel along with the cnservative therapy. However, in some cases, the complete ligation of the anomalous vessel would result in life-threatening portal hypertension caused by increased resistance of blood flow through a poorly developed hepatoportal vascular system. Gradual occlusion of shunt vessels with the ameroid constrictor (AC) has been reported to prevent such acute problems. In this study, we performed the surgical treatment with AC in 4 young dogs with clinical signs of PSS. Three of 4 dogs had an extrahepatic portocaval shunt and the remaining one had a portoazygos shunt. After the treatment with AC, any signs associate with portal hypertension did not appear and their clinical conditions were improved quickly. AC can slow down the occlusion rate of the shunting vessel, which may allow more time for hepatic regeneration to accommodate increased portal blood flow to the liver and prevent from the portal hypertension and the subsequent development of multiple collateral shunts. It is also suggested that measurement of portal pressure may not be necessary when the shunt vessel is occluded by AC.