Liver transplantation in the setting of a spontaneous shunt between superior mesenteric vein and right renal vein

Collaterals in portal hypertension: anatomy and clinical relevance

Portal hypertension is a key pathophysiology of chronic liver diseases typified with cirrhosis or noncirrhotic portal hypertension. The development of collateral vessels is a characteristic feature of impaired portal hemodynamics. The paraumbilical vein (PUV), left gastric vein (LGV), posterior gastric vein (PGV), short gastric vein (SGV), splenorenal shunt (SRS), and inferior mesenteric vein (IMV) are major collaterals, and there are some rare collaterals. The degree and hemodynamics of collateral may affect the portal venous circulation and may compensate for the balance between inflow and outflow volume of the liver. Additionally, the development of collateral shows a relation with the liver function reserve and clinical manifestations such as esophageal varices (EV), gastric varices, rectal varices and the other ectopic varices, hepatic encephalopathy, and prognosis. Furthermore, there may be an interrelationship in the development between different collaterals, showing additional influences on the clinical presentations. Thus, the assessment of collaterals may enhance the understanding of the underlying pathophysiology of the condition of patients with portal hypertension. This review article concluded that each collateral has a specific function depending on the anatomy and hemodynamics and is linked with the relative clinical presentation in patients with portal hypertension. Imaging modalities may be essential for the detection, grading and evaluation of the role of collaterals and may help to understand the pathophysiology of the patient condition. Further investigation in a large-scale study would elucidate the basic and clinical significance of collaterals in patients with portal hypertension and may provide information on how to manage them to improve the prognosis as well as quality of life.

A Single-Center Experience in Portal Flow Augmentation in Liver Transplantation With Prior Large Spontaneous Splenorenal Shunt

Large portosystemic shunts may cause portal steal syndrome in liver transplantation (LT). Because of the possible devastating consequences of the syndrome, the authors recommend perioperative management of these large shunts. Fourteen adult recipients who underwent portal flow augmentation, including left renal vein ligation (LRVL), renoportal anastomosis (RPA), shunt ligation (SL), and splenic vein ligation (SVL) for large spontaneous splenorenal shunt (SSRS), are included in this study, and the results were analyzed. A total of 13 patients had a large SSRS, and in 1 patient, the large shunt was placed between the superior mesenteric vein and the right renal vein. LDLT was performed in 13 patients. LRVL (n = 5), SVL (n = 6), RPA (n = 2), SL (n = 1) were performed to the patients as graft inflow augmentation. The graft-recipient weight ratios (GRWR) were less than 0.8% in 5 patients (35.7%): 2 had LRVL, and 3 had SVL. Small-for-size syndrome (SFSS) occurred only in these 2 patients with LRVL (GRWR ≤0.8%) and, splenic artery ligation was performed for graft inflow modulation. No mortality or serious complications were reported during follow-up. We consider that in patients with large SSRS and small-for-size grafts, SVL can be performed safely and with satisfactory outcomes.