Liver transplantation preserving the retrohepatic interior vena cava, the so-called piggyback technique, is becoming more frequently used because it avoids caval cross-clamping during the anhepatic phase of surgery. However, hepatic venous outflow blockade causing ascites seems to be less infrequent after piggyback than with cavo-caval anastomosis. We report a 62-year-old patient who underwent liver transplantation using the piggyback technique and developed a stenosis in the anastomosis between the hepatic veins and the inferior vena cava leading to severe postoperative ascites. Ascites was unresponsive to diuretic therapy and was associated with renal function impairment. Since the etiology of the stenosis was mechanical (torsion), percutaneous transluminal angioplasty was unsuccessful. Finally, an autoexpandable prosthesis was placed across the anastomosis resulting in rapid and permanent (3 years of follow-up) resolution of ascites.