Extrahepatic Portosystemic Shunts

Team: ¹Schuyler Brennan, ¹Mette Olufsen, ¹Nate Nelson, ¹Sohee Bae

Affiliations: ¹NC State University

Overview:

Congenital extrahepatic portosystemic shunts (cEHPSS) are vascular anomalies characterized by an abnormal vessel that directly connects the portal and systemic venous circulation, allowing portal blood to bypass the liver. The liver has a unique dual blood supply, where the portal vein provides approximately 80% of total hepatic blood flow and carries nutrient-rich blood from the abdominal digestive organs while the hepatic artery supplies the remaining 20%. Consequently, diversion of portal blood through an EHPSS contributes to impaired hepatic function, allowing substances normally metabolized by the liver to enter the systemic circulation. Surgical attenuation is the treatment of choice for a single cEHPSS, as it allows the portal blood flow to be progressively redirected through the liver, providing time for intrahepatic portal vasculature to adapt to the increased flow. Constructing a realistic mathematical model of shunt closure could help enable virtual treatment planning and predict clinical outcomes that are difficult to assess before operating, such as which dogs are most likely to develop post-surgery hypertension. We aim to predict hemodynamics in the portal vasculature by solving a patient-specific one-dimensional fluid dynamics model for dogs with EHPSS capable of making long term predictions of vascular growth and remodeling as the shunt is occluded.