Controversy exists concerning the proper
therapy for
bleeding gastroesophageal
varices secondary to noncirrhotic portal vein
thrombosis. Disparity of opinion exists regarding the significance of hepatic portal blood flow and the consequences of total portal-systemic shunts in this condition. One patient is presented who developed severe, crippling
encephalopathy 20 years after a central
splenorenal shunt. This was associated with loss of portal flow to the liver and marked
nitrogen intolerance. Closure of the shunt resulted in restoration of hepatic portal flow via collateral veins (HPI 0.36), clearance of
encephalopathy and return to near normal
protein tolerance. An additional patient was studied with
hyperammonemia and early suggestive signs of
encephalopathy eight years following a mesocaval shunt. Four patients were evaluated before and after selective distal
splenorenal shunts. All had "cavernous transformation" of the portal vein with angiographic evidence of portal flow to the liver. Postoperative angiograms revealed continued hepatic portal perfusion and a patent shunt in each patient.
Radionuclide imaging postoperatively gave an estimated portal fraction of total hepatic blood flow (HPI) of .39 and .60 in two of the four patients. We conclude that 1) there is significant hepatic portal perfusion in noncirrhotic portal vein
thrombosis (cavernous transformation), 2) loss of this hepatic portal flow following total shunts can lead to severe
encephalopathy, 3) the selective distal
splenorenal shunt maintains hepatic portal perfusion and is the procedure of choice when there is a patent splenic vein and surgical intervention is indicated.