Alternatives for vascular reconstruction in pediatric living donor liver transplantation

Portal Vein Pull-Through Technique and Thrombectomy for Extensive Portal Vein Thrombosis

BACKGROUND

Herein, a different technique is presented describing complete dissection of the entire portal vein (PV), superior mesenteric vein (SMV), and splenic vein, thus enabling a complete thrombectomy without the risk of uncontrolled hemorrhage due to blind thrombectomy.

METHODS

In cases where a thrombectomy would not be an option because of extensive thrombosis involving the confluence of the PV and SMV, small branches of the SMV, including the inferior mesenteric vein, were divided. Both the SMV and splenic vein were encircled separately. Then, the side branches of the PV above the pancreas, left gastric vein on the left side, and superior pancreatoduodenal vein on the right side were divided. The lateral and posterior part of the PV were dissected within the pancreas both from above and below, allowing the main PV completely free from attachments. At this point, the splenic vein and SMV were clamped, and the main PV was divided above the pancreas and then pulled back through the pancreatic tunnel. The thrombus was easily dissected of the vein under direct visualization, and afterward the PV was redirected to its original position. Then, the liver transplant was carried out in a regular fashion.

RESULTS

This technique was applied to 2 patients. The first was a 43-year-old man who underwent a right lobe living donor liver transplant because of hepatitis B virus-related cirrhosis. The patient is still alive and well with stable liver function after 15 years of follow-up. The second was a 69-year-old woman who underwent a right lobe living donor liver transplant because of hepatitis C virus and hepatocellular carcinoma. She survived the procedure and her liver function was entirely normal afterward. She died of pneumonia and sepsis 5 months after transplant.

CONCLUSIONS

This technique enables complete dissection of the entire PV, SMV, and splenic vein. Thus, complete thrombectomy under direct visualization without the risk of uncontrolled hemorrhage can be performed.

Tailored classification of portal vein thrombosis for liver transplantation: Focus on strategies for portal vein inflow reconstruction

Portal vein thrombosis (PVT) is currently not considered a contraindication for liver transplantation (LT), but diffuse or complicated PVT remains a major surgical challenge. Here, we review the prevalence, natural course and current grading systems of PVT and propose a tailored classification of PVT in the setting of LT. PVT in liver transplant recipients is classified into three types, corresponding to three portal reconstruction strategies: Anatomical, physiological and non-physiological. Type I PVT can be removed via low dissection of the portal vein (PV) or thrombectomy; porto-portal anastomosis is then performed with or without an interposed vascular graft. Physiological reconstruction used for type II PVT includes vascular interposition between mesenteric veins and PV, collateral-PV and splenic vein-PV anastomosis. Non-physiological reconstruction used for type III PVT includes cavoportal hemitransposition, renoportal anastomosis, portal vein arterialization and multivisceral transplantation. All portal reconstruction techniques were reviewed. This tailored classification system stratifies PVT patients by surgical complexity, risk of postoperative complications and long-term survival. We advocate using the tailored classification for PVT grading before LT, which will urge transplant surgeons to make a better preoperative planning and pay more attention to all potential strategies for portal reconstruction. Further verification in a large-sample cohort study is needed.

Optimizing hepatic venous outflow reconstruction for hepatic vein stenosis with indwelling stent in living donor liver retransplantation

The patient was a boy of 7 years and 5 months of age, who underwent LDLT for acute liver failure at 10 months of age. HV stent placement was performed 8 months after LDLT because of intractable HV stenosis. At 7 years of age, his liver function deteriorated due to chronic rejection. The patient therefore underwent living donor liver retransplantation from his father. The HV was transected with the stent in situ. The IVC was resected due to stenosis. The pericardial cavity was opened and detached around the IVC to elongate the IVC. The divided ends of the IVC were joined by suturing to the posterior wall of the IVC. A new triangular orifice was made by adding an incision on the anterior wall of the IVC. The graft HV was then anastomosed to the new orifice with continuous sutures in the posterior wall and interrupted sutures in the anterior wall using 5-0 non-absorbable sutures. Doppler ultrasound showed a triphasic waveform. We successfully performed HV reconstruction without a vascular graft. This is a feasible procedure for overcoming HV stenosis in LDLT patients with an indwelling stent.

Renoportal Anastomosis in Left Lateral Lobe Living Donor Liver Transplantation: A Pediatric Case

In adult liver transplantation, renoportal anastomosis (RPA) has been introduced as a useful technique for patients with grade 4 portal vein thrombosis and a splenorenal shunt. Here, we report a pediatric case in which RPA allowed a left lateral lobe living donor liver transplantation (LDLT) despite portal vein thrombosis and a large splenorenal shunt. At 36 days old, the patient underwent a Kasai operation for biliary atresia. At 17 months old, she underwent LDLT because of repetitive cholangitis. Pretransplant examinations revealed a large splenorenal shunt and portal vein thrombosis. Simple end-to-end portal reconstruction and clamping of the collateral route after removing the thrombosis were unsuccessful. Thus, RPA was performed using a donor superficial femoral vein as an interpositional graft. The portal vein pressure was 20 mm Hg after arterial reperfusion. Ligation of the splenic artery reduced the portal vein pressure. Although she developed severe acute cellular rejection and chylous ascites, there were no signs of portal vein complications. She was discharged 73 days after transplantation without any signs of renal dysfunction. The patient's condition was good at her last follow-up, 22 months after transplantation. To our knowledge, this is the youngest case of RPA in pediatric left lateral lobe LDLT. Additionally, this is the first case of RPA with splenic artery ligation and using the donor's superficial femoral vein as the venous graft for RPA. Although long-term follow-up is necessary, RPA could be a salvage option in LDLT in infants if other methods are unsuccessful.