In patients with extrahepatic portal vein obstruction, development of collateral circulation is observed but the blood flow through these new veins is insufficient to maintain normal portal blood pressure.1 As a result, portal hypertension develops, leading to common manifestations such as esophageal varices. With extrahepatic portal vein obstruction, a potential route of decompression is through the normal liver. This route of decompression results in the formation of venous collaterals in the hilum, including the axial veins of the bile duct. The development of varices around the bile duct can cause obstruction of the bile duct, termed portal hypertensive biliopathy.2 Preoperative endoscopic retrograde cholangiopancreatography demonstrated no intrinsic bile duct abnormality but extrinsic compression by cavernoma.
To treat this patient, a variant of a mesenteric-portal shunt, otherwise known as a Rex shunt, was performed using the coronary vein anastamosed to the left portal vein (Figure 2). A successful shunt eliminates portal hypertension and reestablishes portal venous flow to the liver.3 This is accomplished by conveying mesenteric venous and splenic blood past the extrahepatic portal obstruction and into a patent intrahepatic portal venous system.3 With treatment of the portal hypertension, the partial biliary obstruction caused by the biliary varices resolves.
A variant of a mesenteric-portal shunt, otherwise known as a Rex shunt, was performed using the coronary vein anastamosed to the left portal vein.
In its classic form, the Rex shunt is a graft from the superior mesenteric vein that drains both the splenic and superior mesenteric veins via the graft into the left portal venous system, where it drains into the left portal vein and across the pars transverses into the right portal vein. Usually the internal jugular vein is used as the graft. One alternative to the classic Rex shunt is created by connecting the coronary vein to the left portal vein, thus providing decompression of the portal system. Use of the coronary vein has the advantage of avoiding neck dissection to remove the jugular vein and allows the shunt to be created with a single vascular anastamosis, thereby simplifying the procedure.4 If the coronary vein is of adequate size, creation of a coronary–intrahepatic portal shunt could be a preferred method of managing extrahepatic portal vein obstruction.1
During the patient's operation, the liver appeared to be normal. At the time of exploration, the hilum was not visualized because of adhesions. The coronary vein was dissected out, dividing the vein to give an adequate length. It was then anastomosed to the left portal vein in the sinus of Rex. After this, visible blood flow through the wall of the vein was observed and heard with Doppler ultrasonography.
The patient was discharged home well. Follow-up ultrasonographs reveal good flow in the shunt and portal flow to both the left and right lobes. The biliary stent was removed and the patient's liver enzyme levels have remained normal. Ultrasonography demonstrates resolution of the biliary dilation. Laboratory results 14 months after surgery show that the alkaline phosphatase level is 81 U/L (to convert to microkatals per liter, multiply by 0.0167), the albumin level is 4.6 g/dL (to convert to grams per liter, multiply by 10), the bilirubin level is 0.9 mg/dL (to convert to micromoles per liter, multiply by 17.104), and the platelet count is 70 × 103/μL (to convert to ×109 per liter, multiply by 1.0). The patient feels well.
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Correspondence: John P. Roberts, MD, Department of Surgery, Division of Transplant, University of California, San Francisco, PO Box 0780, 505 Parnassus Ave, Room M896, San Francisco, CA 94143 (email@example.com).
Accepted for Publication: January 29, 2010.
Author Contributions:Study concept and design: Roberts. Acquisition of data: Martinez, Bonacini, and Roberts. Analysis and interpretation of data: Martinez, Bonacini, and Roberts. Drafting of the manuscript: Martinez, Bonacini, and Roberts. Critical revision of the manuscript for important intellectual content: Martinez, Bonacini, and Roberts. Administrative, technical, and material support: Martinez. Study supervision: Bonacini and Roberts.
Financial Disclosure: None reported.
Image of the Month—Diagnosis. Arch Surg. 2011;146(5):626. doi:10.1001/archsurg.2011.98-b