Interaction between the splenic and hepatic arteries in portal hypertension.

Abstract

Experimental production of an arterio-venous fistula between the splenic artery and vein of the dog causes increased splenic arterial flow, and reduction of hepatic arterial flow. In the majority of clinical cases of splenomegaly of periportal fibrosis (Banti's syndrome), selective celiac angiography reveals narrowing of the hepatic artery proper, and there is a significant negative correlation between the radii of splenic and hepatic arteries on the x-ray films. The results suggest reduced hepatic arterial flow in such cases. Two different mechanisms are taken into consideration for the explanation of this circulatory condition: There may be some hemodynamical interaction between the portal system and the hepatic artery, or increased blood flow of the splenic artery, or increased blood flow of the splenic artery may reduce the hepatic share of celiac arterial flow. No arteriographical narrowing of the hepatic artery proper was demonstrated in splenomegalic cirrhosis even if high portal inflow is expected through the massive splenomegaly. A comparison of the radius of the hepatic artery proper and the percentage of intrahepatic shunted flow supports the view that the effective portal flow is unchanged in those cases.