Effect of propranolol on portosystemic collateral circulation estimated by per-rectal portal scintigraphy with technietium-99m pertechnetate

Background/Aims: Propanolol is widely used in the prevention of variceal bleeding. However, in certain patients with cirrhosis, the portal hypotensive effect of propanolol cannot be obtained. An explanation for portal unresponsiveness to propanolol could be an increase in portocollateral vascular resistance mediated by this drug. Methods: In 33 patients with cirrhosis the effect of chronic administration of propanolol on portocollateral blood flow from the inferior mesenteric vein was examined by means of per-rectal portal Tc-99m pertechnetate scintigraphy. Results: Propanolol significantly reduced the shunt index by 15.3±4.2%. This reduction was observed only in patients with cirrhosis classified as Child-Pugh A and B groups, but not group C. Differences between groups in portosystemic shunt index changes after propanolol were significant (F=3.4, p<0.05). Conclusions: The data presented suggest that propanolol changes the distribution of blood between the portal and systemic circulation, which is probably due to the increase in vascular resistance of portocollateral vessels. The magnitude of the vascular response to propanolol depends on the severity of liver disease