Outcome and Hepatic Hemodynamics in Liver Transplant Patients with Portal Vein Arterialization

Few cases of successful portal vein arterialization in orthotopic and auxiliary liver transplantation have been reported. AIM: To evaluate the effect of portal vein arterialization on hepatic hemodynamics and long-term clinical outcome in three patients undergoing liver transplantation. METHODS: Two patients with extensive splanchnic venous thrombosis received an orthotopic liver transplant and one with fulminant hepatic failure received an auxiliary heterotopic graft. Portal vein arterialization was performed in all cases. RESULTS: One patient died 4 months after transplant and two are still alive. Auxiliary liver graft was removed 3 months post-transplant when complete native liver regeneration was achieved. Immediate post-transplant liver function was excellent in all cases. Only one patient developed encephalopathy and variceal bleeding owing to prehepatic portal hypertension secondary to arterioportal fistula 14 months after transplant. He was successfully treated by embolization of the hepatic artery. Hepatic hemodynamic measurements demonstrated a normal pressure gradient between wedged and free hepatic venous pressures in all cases. Liver biopsy showed acceptable graft architecture in two cases and microsteatosis in one. CONCLUSIONS: Liver transplantation with portal vein arterialization is an acceptable salvage alternative when insufficient portal venous flow to the graft is present. The double arterial supply does not imply changes in hepatic hemodynamics, at least in the early months post-transplant.     

猪急性缺血性肝衰模型的建立和辅助性异位部分肝移植的作用

目的: 探讨急性缺血性肝衰模型的制备、辅助性异位部分肝移植的作用. 方法: 用家猪配对开展辅助性异位部分肝移植.分三组,A组:受体肝脏和肝动脉保持原状,其门静脉缩窄;供肝植入受体右肝下,仅建立门静脉血供,不建立动脉血供.B组:受体肝动脉结扎,其他手术内容与A组相同.C组:受体肝动脉结扎,供肝动脉和门静脉血供均建立,其他手术内容与A组相同.监测各组受体存活情况,肝功能和肝脏血流情况,病理及供肝胆汁分泌情况. 结果: A组、C组受体3 d以上成活率显著高于B组.A组、C组手术前后胆红素无显著改变,B组术后胆红素显著高于术前,术后第二天B组胆红素显著高于A组、C组.C组供肝胆汁分泌和血供良好,肝细胞存活并有活跃的代偿性增生;A组、B组供肝无或仅有少量胆汁分泌,肝细胞大片坏死. 结论: 受体肝动脉结扎、门静脉缩窄足以造成急性肝衰模型;保留受体肝脏动脉血供、减少门静脉血供对受体肝脏功能无严重影响;辅助性异位部分肝移植能取得良好的效果,足以纠正急性肝衰.     

Auxiliary partial orthotopic liver transplantation in acute liver failure due to hepatitis B

Auxiliary partial orthotopic liver transplantation is an alternative therapeutic modality in acute liver failure, wherein the capacity of native liver to regenerate is preserved. A case of acute liver failure due to hepatitis B in an 18-year-old male patient treated with an auxiliary left lateral segment graft is described. There was no recurrence of hepatitis B in the auxiliary graft and the patient cleared the virus after 9 months whilst receiving lamivudine. Immunosuppression was withdrawn at 14 months, and the auxiliary graft atrophied secondary to hepatic arterial conduit thrombosis, possibly precipitated by immunosuppression withdrawal. The native liver regenerated completely, and the patient is well and off immunosuppressive and antiviral therapy 3 years after transplantation. Auxiliary partial orthotopic liver transplantation is an attractive treatment option in acute liver failure due to hepatitis B infection and allows a life free of long-term immunosuppression.     

Functional portal flow competition after auxiliary partial orthotopic living donor liver transplantation in noncirrhotic metabolic liver disease

Auxilliary partial orthotopic liver transplantation (APOLT) was introduced initially as a tentative or permanent support for patients with potentially reversible fulminant hepatic failure and has extended its indication to congenital metabolic disorder of the liver that has otherwise normal functional integrity. Postoperative management of APOLT is complicated because of functional portal flow competition between the native and graft liver. The native portal vein diversion to the graft is sometimes indicated to prevent functional competition; however, it is still an open question whether this technique can be theoretically indicated for APOLT patients. The authors report a on patient with ornithine transcarbamylase deficiency who received APOLT from a living donor without native portal vein diversion. Because of functional portal vein competition between the native and graft liver, the patient had to have portal vein diversion, portal vein embolization, and finally native hepatectomy to induce the graft regeneration after APOLT. After the experience of the current case, primary portal vein diversion for APOLT with noncirrhotic metabolic liver disease patients to prevent functional portal flow competition is recommended.     

Auxiliary Heterotopic Liver Transplantation With Portal Vein Arterialization for Fulminant Hepatic Failure

Auxiliary liver transplantation for patients with fulminant hepatic failure supports the patient's failing liver for a period of time until the native liver (NL) has recovered and immunosuppression can be withdrawn. Auxiliary heterotopic liver transplantation (AHLT) with portal vein arterialization (PVA) has several advantages over auxiliary orthotopic liver transplantation: NL resection is not required, and the hepatic hilum is left untouched; thus, the chances of liver regeneration are optimal. The successful application of emergency AHLT with PVA in a young patient who developed toxic fulminant hepatic failure caused by tuberculostatic drugs is described. Two and one-half months after the procedure, the NL had completely regenerated; the graft was removed, and immunosuppression was suspended. (Liver Transpl 2000;6:805-809.)     

A Novel Technique for Auxiliary Partial Liver Transplantation With Reno-Portal Anastomosis and Avoidance of the Hepatoduodenal Ligament

Auxiliary liver transplantation (ALT) is a treatment for acute liver failure when regeneration of the native liver is possible or for metabolic disorders. In selected cases ALT and orthotopic liver transplantation (OLT) have similar survival when ALT is performed in the orthotopic position (auxiliary partial orthotopic liver transplantation, APOLT). Drawback of ALT with portal vein to portal vein anastomosis is the frequent occurrence of thrombosis, compromising both graft and native liver, and the necessity of a significant resection. To avoid division of portal flow we performed ALT with an end-to-end anastomosis between the graft portal vein and the left renal vein of the recipient (reno-portal ALT, REPALT). The hepatic artery was anastomosed to the aorta using an iliac arterial graft conduit. The bile duct was anastomosed to the stomach. In the two cases presented here excellent immediate graft function occurred with rapid regeneration of the graft and without early vascular complications.     

Heterotopic segmental liver transplantation on splenic vessels after splenectomy with delayed native hepatectomy after graft regeneration: A new technique to enhance liver transplantation

We describe a patient with liver metastases from colorectal cancer treated with chemotherapy and hepatic resection, who developed unresectable multifocal liver recurrence and who received liver transplantation using a novel planned technique: heterotopic transplantation of segment 2-3 in the splenic fossa with splenectomy and delayed hepatectomy after regeneration of the transplanted graft. We transplanted a segmental liver graft after in-situ splitting without any impact on the waiting list, as it was previously rejected for pediatric and adult transplantation. The volume of the graft was insufficient to provide liver function to the recipient, so we performed this novel operation. The graft was anastomosed to the splenic vessels after splenectomy, and the native liver portal flow was modulated to enhance graft regeneration, leaving the native recipient liver intact. The volume of the graft doubled during the next 2 weeks and the native liver was removed. After 8 months, the patient lives with a functioning liver in the splenic fossa and without abdominal tumor recurrence. This is the first case reported of a segmental graft transplanted replacing the spleen and modulating the portal flow to favor graft growth, with delayed native hepatectomy.     

Auxiliary liver transplantation: how to improve regeneration of the native liver by surgery

The technical factors which could influence regeneration of the native liver (NL) in auxiliary liver transplantation (ALT) for fulminant hepatic failure (FHF) are not well known. We studied NL regeneration according to the location of graft anastomosis in the recipient's portal system (superior mesenteric vein versus portal vein), and graft weight (50 % reduced-size versus full-size graft) in a rat model of ALT with 80 % reduction of the NL, and graft arterialization. NL regeneration was significantly more obvious when the graft was anastomosed on the recipient's superior mesenteric vein, thus establishing venous flow to the NL from the pancreas, the spleen, and the stomach, and when a full-size graft was used. The influence of portal venous flow on NL regeneration, assessed by [³H]-thymidine incorporation, was measurable as early as day 2. Both technical variables in combination resulted in significantly greater regeneration (ratio weight of NL/body weight at day 30: 2.32 ± 0.68 % versus 1.21 ± 0.63 % respectively, P = 0.02). Early preservation of portal flow to the NL is advisable to maximize NL regeneration in ALT. In any case, this regeneration is not impeded by the use of large auxiliary grafts. Received: 11 February 1999 Received after revision: 29 July 1999 Accepted: 1 September 1999     

Arterialization of the portal vein in pediatric liver transplantation

Portal vein arterialization (PVA) is an acquired concept in shunt surgery for portal hypertension. This technique, recently described as both a temporary and permanent procedure in adult liver transplantation, is reported by the authors in two cases of pediatric transplantation. The indication was low portal blood flow after reperfusion with poor graft function due to persistence of spontaneous retroperitoneal venous shunts. In both cases described, PVA allowed for satisfactory macroscopic liver reperfusion. The increase in portal blood flow from 150 to 500 ml/min in the second patient enabled the liver to be reperfused correctly and led to successful transplantation. The graft function in both cases improved in the 1st postoperative week, but thrombosis of the PVA occurred in the 1st patient 2 months after transplantation. Signs of hepatic hyperarterialization occurred in the second patient and this necessitated a dearterialization of the portal vein 2 weeks later. Although the benefit of this procedure appears to be beyond doubt in the immediate postoperative period, we have no data on long-term arterialization. We do think that PVA can be performed in pediatric liver transplantation, but it may need to be done only in special, individual situations when no valid alternative can be proposed, such as in the absence of a mesenteric vein and/or the presence of spontaneous retroperitoneal venous shunts. Received: 24 June 1997 Received after revision: 27 November 1997 Accepted: 28 November 1997     

Cryopreserved iliac artery allograft for primary arterial revascularization in adult liver transplantation

Arterial allograft represents a material of choice for primary arterial revascularization in liver transplantation (LT) when interposition of a vascular conduit is required. In case of non-availability of such graft, the use of cryopreserved vessels should be an interesting option. Three patients were grafted using a cryopreserved iliac artery allograft (CIAA) previously harvested and stored at -140°C in a tissue bank. An auxiliary partial LT was performed in one patient for acute liver failure. During follow-up, an efficient regeneration of the native hemi-liver was observed while atrophy of the auxiliary graft occurred, leading to functional portal vein and hepatic artery thrombosis at six and nine months, respectively. Two other patients presented with celiac trunk compression because of arcuate ligament without available arterial allograft in the donor. Late arterial thrombosis occurred at six months in one patient without impairment of graft function. The last patient was alive and symptom free 29 months after LT with a patent cryopreserved arterial conduit. Our preliminary results suggest that CIAA might represent an efficient solution as vessel interposition for primary arterial hepatic revascularization in LT setting when no other suitable graft is available. However, long-term patency of CIAA remains questionable.     

Improved technique of heterotopic auxiliary rat liver transplantation with portal vein arterialization

BACKGROUND AND AIMS: In acute, potentially reversible hepatic failure, auxiliary liver transplantation is a promising alternative approach. Using the auxiliary partial orthotopic liver transplantation (APOLT) method--the orthotopic implantation of auxiliary segments--most of the technical problems (lack of space for the additional liver mass, the portal vein reconstruction, and the venous outflow) are avoided, but extensive resections of the native liver and the graft are necessary. Erhard described the heterotopic auxiliary liver transplantation (HALT) with portal vein arterialization (PVA). Initial clinical results demonstrated that an adequate liver function can be achieved using this technique. We developed and improved a technique of HALT with flow-regulated PVA in the rat to perform further investigations. The aim of this paper is to explain in detail this improved experimental surgical technique. MATERIALS AND METHODS: Liver transplantations were performed in 122 male Lewis rats: After a right nephrectomy, the liver graft, which was reduced to about 30% of the original size, was implanted into the right upper quadrant of the recipient's abdomen. The infrahepatic caval vein was anastomosed end-to-side. The donor's portal vein was completely arterialized to the recipient's right renal artery in stent technique. Using a stent with an internal diameter of 0.3 mm, the flow in the arterialized portal vein was regulated to achieve physiologic parameters. The celiac trunk of the graft was anastomosed to the recipient's aorta, end-to-side. The bile duct was implanted into the duodenum. RESULTS: After improvements of the surgical technique, we achieved a perioperative survival of 90% and a 6-week survival of 80% in the last 112 transplantations. CONCLUSION: We developed a standardized and improved technique, which can be used for experiments of regeneration and inter-liver competition in auxiliary liver transplantation. Furthermore, this technique is suitable for the investigation of the influence of portal vein arterialization and portal hyperperfusion on liver microcirculation, function, and morphology.     

Auxiliary rat liver transplantation with portal vein arterialization in acute hepatic failure

BACKGROUND: The aim of our work was to study the effect of the portal vein arterialization of an auxiliary liver graft on survival, liver function, and regeneration of the native liver suffering from surgically induced acute liver failure (ALF). METHODS: In Lewis rats (control group: n=10), ALF was induced by resection of about 85% of liver tissue. The auxiliary liver graft (reduced size of 30%) was transplanted into the right upper quadrant of the abdomen (trial group: n=12). The portal vein was arterialized via the renal artery. The infrahepatic vena cava was anastomosed end-to-side, and the bile duct was implanted into the duodenum. RESULTS: Survival rate over a 3-month period was 10/12 in the trial group vs. 2/10 in the controls. In the trial group, the prothrombin time rose up to 38+/-2 sec on day 1 after surgery (control group: 66+/-6 sec); on day 5 after surgery, it returned to values of 30+/-1 sec. On day 1 after surgery, serum albumin fell to 25+/-1 g/L (preoperative value: 32+/-1 g/L). Within 3 weeks, it returned to normal. The hepatobiliary scan on day 7 after surgery showed normal uptake in the liver graft, whereas the uptake of the native liver was distinctly reduced. After 3 months, the transplanted liver had atrophied (0.6% of body weight), the native liver hypertrophied (2.5% of body weight), with a normal total weight for both livers of 3.1% of body weight. CONCLUSIONS: Thus, auxiliary liver transplantation with arterialized portal vein allows maintenance of liver function at the time of ALF and regeneration of the native liver.     

Directing portal flow is essential for graft survival in auxiliary partial heterotopic liver transplantation in the dog.

BACKGROUND/PURPOSE: Auxiliary liver transplantation is an attractive alternative for orthotopic liver transplantation in patients with certain inborn errors of metabolism of the liver in which complete resection of the liver is unnecessary or even contraindicated. Because in these diseases portal hypertension is mostly absent, finding a balance in portal blood distribution between native liver and graft is complicated. The objective of this study was to investigate requirements for long-term (180 days) graft survival in auxiliary partial heterotopic liver transplantation (APHLT) in a dog model. METHODS: A metabolic defect was corrected in 26 dalmation dogs with a 60% beagle heterotopic auxiliary liver graft. Four groups of different portal inflow were studied. In the ligation group the portal vein to the host liver was ligated. In the split-flow group graft and host liver received separate portal inflow. In the banding group the distribution of the portal flow was regulated with an adjustable strapband and in the free-flow group the portal blood was allowed to flow randomly to host or graft liver. RESULTS: Metabolic correction increased in all groups after transplantation from 0.19 +/- 0.02 to 0.70 +/- 0.05 (P< .0001) but remained significantly better in the ligation and split-flow groups (graft survival, 135 +/- 27 and 144 +/- 31 days). In the banding group metabolic correction decreased significantly after 70 days, and although the grafts kept some function for 155 +/- 14 days, in 4 of 6 dogs portal thrombosis was found. In the free-flow group, competition for the portal blood led to reduced correction within 12 days and total loss of function in 96 +/- 14 days. Graft function also was assessed with technetium (Tc) 99m dimethyl-iminodiacetic acid uptake. A good linear association between HIDA uptake and metabolic correction was observed (r = 0.74; P < .0005). Grafts that contributed more than 15% to the total uptake of HIDA showed biochemical correction. This indicates a critical graft mass of about 15% to 20% of the hepatocyte volume to correct this metabolic defect. CONCLUSION: Auxiliary partial heterotopic liver transplantation can be a valuable alternative treatment for inborn errors of hepatic metabolism if the native liver and the graft receive separate portal blood inflow.     

Portal flow diversion is essential for graft survival in canine auxiliary partial orthotopic liver transplantation

After auxiliary partial orthotopic liver transplantation for inborn errors of metabolism, finding a balance in portal blood flow distribution between native liver and graft is complicated. We investigated the correction of hypoallantoinuria in the Dalmatian dog with a reduced-size Beagle orthotopic auxiliary liver graft, depending on intra-operative intervention in the portal flow. There were three groups: a ligation group, where the host portal vein was tied off, a free-flow group with random flow to both livers and a banding group, where the host portal vein was banded with an adjustable strapband. Metabolic correction was initially seen in all groups, but ligation led to portal hypertension and early mortality. In the free-flow group, correction was lost after 7 days, while banding preserved correction until 6 weeks. We conclude that acute ligation can lead to portal hypertension and free-flow leads to hypoperfusion and early loss of metabolic correction. Banding divided the portal blood flow between host liver and graft and prolonged metabolic correction.     

Portal vein aneurysm as late complication of liver transplantation: a case report

OBJECTIVE: A case of intrahepatic portal vein aneurysm in the late postoperative period after liver transplantation, as well its complications, is reported. CASE REPORT: A 59-year-old man underwent orthotopic liver transplantation in 1996 for treatment of hepatitis C virus cirrhosis. The patient received a graft from a 10-year-old child. During the follow-up from 1996 to 1998, the patient did not show any alterations. In 1999, during an annual routine exam, a portal vein aneurysm was identified; however, it had no impact on graft function. In November 2002, the patient developed jaundice and serious graft dysfunction requiring hospital admission. Helicoidal CT scan showed an intrahepatic image compatible with a portal vein aneurysm without biliary tract dilatation. During the same hospitalization, he developed upper gastrointestinal bleeding due to variceal rupture as well as kidney and liver failure, and expired on December 31, 2002. The necropsy demonstrated an intrahepatic portal vein aneurysm with portal vein thrombosis and chronic liver disease. The evolution in this case suggests that if there is an intrahepatic portal vein aneurysm after liver transplantation, the patient is likely to experience an eventual recurrence of portal hypertension; retransplant may be an alternative.     

Portal vein thrombosis after intraportal hepatocytes transplantation in a liver transplant recipient

Hepatocytes transplantation is viewed as a possible alternative or as a bridge therapy to liver transplantation for patients affected by acute or chronic liver disorders. Very few data regarding complications of hepatocytes transplantation is available from the literature. Herein we report for the first time a case of portal vein thrombosis after intraportal hepatocytes transplantation in a liver transplant recipient. A patient affected by acute graft dysfunction, not eligible for retransplantation, underwent intraportal infusion of 2 billion viable cryopreserved ABO identical human allogenic hepatocytes over a period of 5 h. Hepatocytes were transplanted at a concentration of 14 million/ml for a total infused volume of 280 ml. Doppler portal vein ultrasound and intraportal pressure were monitored during cell infusion. The procedure was complicated, 8 h after termination, by the development of portal vein thrombosis with liver failure and death of the patient. Autopsy showed occlusive thrombosis of the intrahepatic portal vein branches; cells or large aggregates of epithelial elements (polyclonal CEA positive), suggestive for transplanted hepatocytes, were co-localized inside the thrombus.     

Auxiliary heterotopic partial liver transplantation in pigs with acute liver failure

Fulminant hepatic failure is usually fatal without liver transplantation; however, orthotopic liver transplantation is often difficult to perform due to the high risk of coagulopathy and the development of multiple organ failure. Auxiliary heterotopic partial liver transplantation (APLT), however, has the potential to provide an effective hepatic support system considering that the host liver is left in situ and the surgical procedure is less invasive. In this report, we describe the beneficial effects of performing 60% APLT on the hepatic function and survival of pigs with acute hepatic failure induced by hepatic artery ligation. The pigs were divided into a control group of nine animals (group 1) that had portal vein and hepatic artery ligation with a side-to-side portacaval shunt, and an APLT group of seven animals (group 2) that had portal vein and hepatic artery ligation with APLT. The two left lateral lobes of the donor liver were resected, reducing the liver weight to about 60%, and the graft was placed in the right subhepatic space. No deaths occurred intraoperatively. In group 1, eight pigs died of massive liver necrosis within 48 h and one died between 48 and 72 h (median surivival 23 h). In group 2, two pigs died within 72 h due to preservation or anesthetic problems, but five survived for more than 3 days (median survival 13.4 days), with a significant difference between the two groups (P<0.05). One animal was killed 30 days after APLT and excellent graft function was demonstrated by the synthesis of clotting factors, ammonia detoxification, and glucohomeostasis. Moreover, evidence of hepatic regeneration was found in the transplanted livers. These results indicate that APLT provides metabolic support and improves survival in animals with induced acute liver failure.     

Portal blood flow and liver regeneration in auxiliary partial orthotopic liver transplantation in a canine model

Functional competition has been shown to lead to a detrimental outcome in auxiliary liver transplantation. We evaluated the interaction in auxiliary partial orthotopic liver transplantation between the native liver and the graft in terms of portal flow and regeneration. The need for diversion of the portal flow to the graft was also assessed. Reduced-size liver grafts were transplanted orthotopically after partial hepatectomy in beagles. There were two groups: the preserved group, where portal inflow to the native liver was preserved, and the ligated group, where it was interrupted. Portal flow was measured serially and liver regeneration was evaluated on postoperative day 5. Functional competition was not observed in the preserved group. On the other hand, ligation of the native liver portal vein had no obviously detrimental effects on the remnant native liver. This leads to the conclusion that the portal vein to the native liver can be safely ligated to prevent functional competition.     

大鼠辅助性肝移植诱导免疫耐受模型的建立

目的利用PVG（TR-1^c）和DA（RT-1^a）大鼠分别为供受体，联合进行辅助性肝移植和异位心脏移植，建立大鼠辅助性肝移植诱导免疫耐受模型。方法辅助性肝移植采用重建门静脉法，异位心脏移植采用腹腔吻合法。结果同品系对照组和实验组动物及其移植心脏存活超过100d，而异品系对照组移植心脏只存活7d。结论在受体肝脏存在的情况下，辅助性供肝依然发挥其诱导耐受的效应。经长期观察，供肝无萎缩，耐受诱导效应持续存在，指示心脏搏动良好。因此，该模型在肝移植基础研究中具有实用价值。     

Renal-splenic shunt for infrahepatic caval occlusion after piggy-back liver transplantation

Inferior vena cava thrombosis after liver transplantation is uncommon. We describe a case of this unusual complication occurring after piggy-back (end-to-side) graft implantation. Renal failure, lower limb edema, and hemodynamic instability were the presenting symptoms requiring immediate surgical correction with a left renal-to-splenic vein shunt over a ringed 2.5-cm prosthesis. The decision to go ahead with the shunt was preceded by an intraoperative confirmation of a 10-cm H₂O pressure gradient between the caval and portal circulations. This gradient, unlike that observed in liver cirrhosis, ultimately turned a splenorenal shunt into a renal-splenic one. Six months after the procedure, the patient is alive and well with normal liver and renal function. The technique described may be useful in the management of other clinical conditions of acute infrahepatic caval hypertension. Received: 17 January 1997 Received after revision: 2 May 1997 Accepted: 13 May 1997