Abstract
The blood flow dynamics of peripheral veins in the splenic hilum and marginal regions were observed using Doppler ultrasonography. In patients in whom peripheral vein blood flow waveforms exhibited arterial pulsation, suggestive of diffuse arteriovenous shunts, the dynamics of these veins, the degree of splenomegaly, and the presence of ascites were evaluated. A total of 324 patients comprising 164 men, and 160 women with a median age of 66 years (range: 18 to 93 years) were included in the study. In patients without splenomegaly, peripheral venous blood flow in the splenic marginal region exhibited steady flow with velocities around 8 cm/s, and arterial pulsatile flow was not observed. “Diffuse A-V shunt” blood flow in the splenic marginal region was observed in various chronic liver diseases, including idiopathic portal hypertension (IPH). This phenomenon occurred more frequently in patients with severe splenomegaly, and ascites was present in nearly all patients where this phenomenon was observed. The blood flow velocity in the peripheral veins of the spleen increased in correlation with the degree of splenomegaly. Thus, it was considered that diffuse A-V shunts appear against the background of increased splenic blood flow and are associated with exacerbation of portal hypertension.
