Effects of Propranolol on Azygos Venous Blood Flow and Hepatic and Systemic Hemodynamics in Cirrhosis

Abstract

The effects of propranolol on blood flow through gastroesophageal collaterals and on systemic and hepatic hemodynamies were investigated in 23 cirrhotic patients with portal hypertension. Gastroesophageal collateral blood flow was evaluated by the measurement of azygos venous blood flow by continuous thermal dilution. Azygos venous blood flow was markedly increased in these patients (544 ± 48 ml per min, as compared with 132 ± 18 ml per min in subjects without portal hypertension (p < 0.001). Propranolol at doses achieving effective β-blockage (83 ± 5 mg) (mean ± S.E.M.) markedly reduced azygos venous blood flow (to 354 ± 34 ml per min, p < 0.001). Reduction of azygos venous blood flow (-34.2 ± 3.6%) was significantly greater (p < 0.01) than reductions in cardiac output (-22.6 ± 1.9%), hepatic venous pressure gradient (-11.5 ± 2.4%) and hepatic blood flow (-13.4 ± 7.4%). The hemodynamic effects of propranolol were not related to plasma norepinephrine levels. Reduction of gastroesophageal collateral blood flow may be the mechanism by which oral propranolol therapy reduces the risk of repeated episodes of variceal bleeding in cirrhotic patients with portal hypertension.