Immediate and long-term portal hemodynamic consequences of small-diameter H-graft portacaval shunt

Effective hepatic blood flow is thought to play a critical role in outcome following portal decompressive procedures. We have shown previously that hepatic arterialization occurs soon after shunting, preserving nutrient flow, but the remote effects of shunting are unknown. The purpose of this study was to determine the effect of small-diameter prosthetic H-graft portacaval shunt (HGPCS) on effective hepatic blood flow (EHF) and portal pressures 1 year from shunt placement.

Patients undergoing 8-mm HGPCS had effective hepatic blood flow determined using low-dose galactose clearance preoperatively, postoperatively, and at 1 year postshunt. Portal blood flow, pressures, and portal vein/inferior vena cava pressure gradients were determined intraoperatively before and after shunt placement and at 1 year.

Twenty patients undergoing shunting had flows measured. All patients had significant reductions in portal vein/inferior vena cava pressure gradients while effective hepatic flow was maintained immediately postoperatively. At 1 year following shunting, effective hepatic blood flow was significantly lower than both pre- and postoperative rates of flow while portal pressures and gradients were significantly increased. Albumin, cholesterol, and PT were improved at 1 year while total bilirubin was slightly worse. Nineteen of 20 patients are still alive with average follow-up of 26 +/- 10.3 months. Four patients were encephalopathic preop, 5 postop, and none chronically.

Recollateralization of varices and progression of cirrhosis may account for the observed reductions in EHF at 1 year. Regardless of the cause, diminution of EHF at 1 year is well compensated as demonstrated by minimal encephalopathy and ascites, improved hepatic function reflected in blood chemistry profiles, and good survival.