Portosystemic shunt for the treatment of portal vein thrombosis following orthotopic liver transplantation

Abstract The efficacy of the portosystemic shunt operation for the treatment of portal vein thrombosis following orthotopic liver transplantation was demonstrated. From 1 July 1988 to 31 December 1991 42 portosystemic shunt operations were performed at our centre. In six of these cases portal vein thrombosis after orthotopic liver transplantation (OLT) was the indication for the procedure. All the patients retained adequate liver function but they demonstrated manifestations of significant portal hypertension, mainly variceal rebleeding. Two of the patients were children. Three patients underwent distal splenorenal shunt (DSRS), one mesocaval and one side-to-ide splenorenal shunt and the last one side-to-ide splenorenal shunt which was converted to DSRS 2 weeks later. All these patients were doing well after 30 months mean follow-up time without rebleeding or other signs of portal hypertension and none had so far required retransplantation.     

Intra-operative management of low portal vein flow in pediatric living donor liver transplantation

For pediatric living donor liver transplantation, portal vein complications cause significant morbidity and graft failure. Routine intra-operative Doppler ultrasound is performed after graft reperfusion to evaluate the flow of portal vein. This retrospective study reviewed 65 children who had undergone living donor liver transplantation. Seven patients were detected with suboptimal portal vein flow velocity following vascular reconstruction and abdominal closure. They underwent immediate on-table interventions to improve the portal vein flow. Both surgical and endovascular modalities were employed, namely, graft re-positioning, collateral shunt ligation, thrombectomy, revision of anastomosis, inferior mesenteric vein cannulation, and endovascular stenting. The ultrasonographic follow-up assessment for all seven patients demonstrated patent portal vein and satisfactory flow. We reviewed our experience on the different modalities and proposed an approach for our future intra-operative management to improve portal vein flow at the time of liver transplantation.     

Selective variceal decompression in portal vein thrombosis

Thirty-two patients with congenital portal vein thrombosis have been managed for bleeding gastro-oesophageal varices. Fifteen had splenectomy and/or other therapy before referral: nine were managed by endoscopic sclerosis, four by devascularization and two by total shunt; six rebled. Seventeen had their spleen 'in situ' at referral and were evaluated for selective shunt: thirteen had distal splenorenal shunts (DSRS)--one transiently rebled despite a patent shunt and one had shunt thrombosis; four had no veins suitable for shunt, and were managed by splenectomy and devascularization, with two rebleeds. Detailed study of seven patients before, and 1 year after DSRS, showed a rise in platelet count, maintenance of hepatocyte function, portal perfusion, liver blood flow and liver size. The spleen showed a significant (P less than 0.025) reduction in size with trans-splenic decompression. We conclude that DSRS provides an excellent method for long-term control of bleeding in such patients, without alteration of liver function or haemodynamics. Patients managed by splenectomy and direct ablative procedures have a significantly (P less than 0.05) greater risk of rebleeding than patients receiving DSRS.     

Left renal vein ligation for large splenorenal shunt during liver transplantation

Adequate hepatopetal portal vein blood flow is obligatory to ensure proper liver function after liver transplantation. Large collateral veins as shunts impair portal vein flow and even cause hepatofugal blood flow and portal steal syndrome. In particular, splenorenal shunts in liver transplant recipients can lead to allograft dysfunction and possible allograft loss or hepatic encephalopathy. Restoration of portal flow through left renal vein ligation (LRVL) is a treatment option, which is much easier compared to splenectomy, renoportal anastomosis and shunt closure, but bears the risk of moderate and temporary impairment of renal function. In addition, a patent portal vein is mandatory for LRVL. However, although LRVL has been reported to be an effective, safe and easy method to control portacaval shunts and increase hepatopetal flow in some studies, indications and safety are still not clear. In this review, we summarize existing studies on LRVL during liver transplantation.     

Liver transplantation in patients with portal vein thrombosis and central portacaval shunts.

The authors have analyzed the impact of pre-existing portal vein pathology on the outcome of orthotopic liver transplantation. The incidence was high in patients suffering from chronic active hepatitis, hypercoagulable states, trauma or previous dissection of the porta hepatis, and splenectomy. The existence of portal vein thrombosis (23 patients) or surgical central portosystemic shunt (10 patients) was documented by preoperative Doppler sonogram or angiography (26/33), or operative findings of occluded vein (7/33). Successful thrombectomy and dismantling of portacaval shunts were achieved in most cases (24/33). Only nine patients required the placement of an interposition vein graft to the superior mesenteric vein. The intraoperative course was characterized by increased blood loss and coagulopathy, significantly higher than in patients with a patent portal vein. When compared with all liver transplants, the immediate postoperative complication rate was higher for primary nonfunction (33% versus 8%), re-exploration for intraperitoneal bleeding and hematomas, and morbid infections. Rethrombosis rate of thrombectomized veins or vein graft was low (2/33). The mortality rate was 35% in the presence of portal vein thrombosis (PVT) and 30% for portacaval shuct (PCS), both significantly higher than the 12% for other orthotopic liver transplant (OLT) patients. These results are expected to improve with better patient selection, surgical experience, and anticipation of the complex postoperative course. The authors conclude that PVT or the presence of PCS are not contraindications to orthotopic liver transplantation.     

Arterialization of the portal vein in liver transplantation: a new microsurgical model in the rat

BACKGROUND: A preexisting thrombosis of the portal vein and the deep splanchnic bed can make it extremely difficult to reestablish the portal blood flow in orthotopic liver transplantation in man. Complete arterialization of the liver transplant, including the donor portal vein, might be a viable therapeutic option. A new rat transplantation model is described, in which the liver is completely arterialized. METHODS: The outflow of the portal blood in the recipient was secured via a portocaval shunt. Hepatectomy was then performed and the liver transplant placed in orthotopic position. An interposed aortic segment was used for direct arterialization of the donor portal vein. RESULTS: The laboratory parameters determined in the serum at the end of the observation period of 28 days revealed normal functioning of the transplant. The histological examinations showed largely normal cellular architecture, with no signs of necrosis, but incipient fibrosis. CONCLUSIONS: Using this new surgical technique in the rat liver transplantation model, long-term morphological and functional changes in a completely arterialized liver graft, and the regenerative capability of liver tissue perfused in this way, can be investigated.     

Ligation of Left Renal Vein as a Salvage Procedure for Splenorenal Shunt After Living Donor Liver Transplantation: A Case Report

We describe a case of recovered portal flow by ligation of the left renal vein (LRV) as a salvage procedure for a spontaneous splenorenal shunt (SRS) occurring the next day after right liver living donor transplantation (LDLT). Doppler ultrasonography showed normal graft portal venous flow immediately after LDLT, but nearly total diversion of portal flow into the existing splenorenal shunt was observed on the next day. Portal flow normalized after ligation of the LRV by relaparotomy. The patient recovered fully without complication and was discharged on the 17th postoperative day. He remains well at 14 months after the operation, returning to his previous occupation. This case was neither associated with acute rejection nor with small-for-size graft, which may increase intrahepatic vascular resistance, causing portal flow steal through shunts. Even though patients with preoperative SRS show normal portal flow immediately after transplantation, close monitoring is necessary for a possible decrease or loss of portal flow. If portal flow becomes insufficient, ligation of LRV as a salvage procedure is an important option that can be considered even after transplantation.     

门静脉-下腔静脉吻合术预防活体肝移植术后小肝综合征3例报道

目的探讨门静脉-下腔静脉吻合术用于预防活体肝移植术后小肝综合征(small-for-size liver syndrome,SFSS)的效果。方法 3例活体肝移植均采用不含肝中静脉的右半肝作为移植物。术中发现实测移植物(肝)重量/受体的体质量(体重)的比值(graft to recipient weight ratio,GRWR)为0.58%、0.77%及0.71%,均<0.8%,符合小移植物的诊断。处理:首先吻合肝静脉流出道,其次吻合门静脉,将受体门静脉右支与移植肝门静脉右支端端吻合,将受体门静脉左支与下腔静脉行端侧吻合达到门腔分流的作用,之后按顺序吻合动脉和胆道。术中均未行脾静脉结扎或脾切除等处理。术后定期随访。结果 3例患者术后均未发生SFSS并顺利出院,出院时间分别为术后25d、34d及56d。移植肝功能逐步好转,术后1d门静脉流速理想。移植肝增长良好。门静脉-下腔静脉短路通畅时间:除1例通畅持续仅104d,其余2例持续通畅。结论 LDLT术中进行门静脉-下腔静脉吻合术可以及时有效预防小移植物背景下的SFSS,受体门静脉左支与下腔静脉行端侧吻合的分流技术安全可靠。     

Living Donor Liver Transplantation with Left Liver Graft

Small-for-size syndrome in LDLT is associated with graft exposure to excessive portal perfusion. Prevention of graft overperfusion in LDLT can be achieved through intraoperative modulation of portal graft inflow. We report a successful LDLT utilising the left lobe with a GV/SLV of only 20%. A 43 year-old patient underwent to LDLT at our institution. During the anhepatic phase a porto-systemic shunt utilizing an interposition vein graft anastomosed between the right portal branch and the right hepatic vein was performed. After graft reperfusion splenectomy was also performed. Portal vein pressure, portal vein flow and hepatic artery flow were recorded. A decrease of portal vein pressure and flow was achieved, and the shunt was left in place. The recipient post-operative course was characterized by good graft function. Small-for-size syndrome by graft overperfusion can be successfully prevented by utilizing inflow modulation of the transplanted graft. This strategy can permit the use of left lobe in adult-to-adult living donor liver transplantation.     

Application of cryopreserved vein grafts as a conduit between the coronary vein and liver graft to reconstruct portal flow in adult living liver transplantation

Abstract:  Adult-to-adult living donor liver transplantation is an alternative to donation from a deceased individual, and can help relieve the shortage of liver donations available for adult patients in Asian countries. When transplant candidates have thrombosis and deterioration of the portal vein, living donor liver transplantation is relatively contraindicated because portal veins in the grafts are short and vein grafts may not be available to reconstruct the portal vein. From June 2003 to May 2007, 82 adult living donor liver transplantations were performed at Chang-Gung Memorial Hospital. Three patients had portal vein thrombosis and marked fibrosis of the portal vein and cryopreserved vein grafts were used to reconstruct portal flow from the engorged coronary vein to the graft portal vein. All vein grafts are patent and all patients have normal liver function at 21–36 months after transplantation. When cryopreserved vein grafts are available, adult living donor liver transplantation can be successfully performed in patients with marked deterioration of the portal vein. The short distance from the engorged coronary vein to the graft portal vein may decrease the incidence of re-thrombosis of the venous conduit.     

Mesorenal shunt using inferior mesenteric vein and left renal vein in a case of LDLT

Adult-to-adult living donor liver transplantation (LDLT) has become an established treatment option around the world. However, small-for-size graft syndrome remains one of the most serious complications affecting transplant outcomes. Excessive portal hypertension and overperfusion have been shown to play a causative role in this graft injury. Recently, portal hypertension per se has been considered detrimental to graft function, and thus to be avoided for successful outcomes after LDLT. We constructed a mesorenal shunt with anastomosis of the inferior mesenteric vein and left renal vein in the case of an LDLT recipient who showed high portal vein pressure after graft reperfusion. The inferior mesenteric vein is close to the left renal vein, and the anastomosis was obtained with relative ease. The shunt was effective in decreasing portal vein pressure, and postoperative graft function was satisfactory. This new method represents an option for attenuating portal hypertension when elevated portal vein pressure is observed in adult LDLT after graft reperfusion.     

Left lobe adult-to-adult living donor liver transplantation: Should portal inflow modulation be added?

Recently, the successful application of portal inflow modulation has led to renewed interest in the use of left lobe grafts in adult-to-adult living donor liver transplantation (LDLT). However, data on the hepatic hemodynamics supporting portal inflow modulation are limited, and the optimal portal circulation for a liver graft is still unclear. We analyzed 42 consecutive adult-to-adult left lobe LDLT cases without splenectomy or a portocaval shunt. The mean actual graft volume (GV)/recipient standard liver volume (SLV) ratio was 39.8% ± 5.7% (median = 38.9%, range = 26.1%-54.0%). The actual GV/SLV ratio was less than 40% in 24 of the 42 cases, and the actual graft-to-recipient weight ratio was less than 0.8% in 17 of the 42 recipients. The mean portal vein pressure (PVP) was 23.9 ± 7.6 mm Hg (median = 23.5 mm Hg, range = 9-38 mm Hg) before transplantation and 21.5 ± 3.6 mm Hg (median = 22 mm Hg, range = 14-27 mm Hg) after graft implantation. The mean portal pressure gradient (PVP - central venous pressure) was 14.5 ± 6.8 mm Hg (median = 13.5 mm Hg, range = 3-26 mm Hg) before transplantation and 12.4 ± 4.4 mm Hg (median = 13 mm Hg, range = 1-21 mm Hg) after graft implantation. The mean posttransplant portal vein flow was 301 ± 167 mL/minute/100 g of liver in the 38 recipients for whom it was measured. None of the recipients developed small-for-size syndrome, and all were discharged from the hospital despite portal hyperperfusion. The overall 1-, 3-, and 5-year patient and graft survival rates were 100%, 97%, and 91%, respectively. In conclusion, LDLT with a left liver graft without splenectomy or a portocaval shunt yields good long-term results for adult patients with a minimal donor burden.     

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.     

Cavoportal hemitransposition for unrecognized spontaneous mesocaval shunt after liver transplantation: a case report

Spontaneous portosystemic shunts can steal the blood away from the portal system. This may result in graft dysfunction or even loss following liver transplantation and can be sorted by shunt occlusion based on intraoperative flow measurements. Herein, we present an alternative technique with cavoportal hemitransposition performed for unrecognized spontaneous mesocaval shunt with ‘portal steal’ syndrome and primary graft nonfunction diagnosed first day following the transplant. This was chosen as a rescue strategy because an attempt to locate the shunt during relaparotomy was unsuccessful. As there was no improvement, emergency liver retransplantation with preservation of the cavoportal hemitransposition was performed on the fourth day after the primary transplant with good long‐term outcome. We conclude that cavoportal hemitransposition during or after liver transplantation can be used to provide an adequate inflow into the donor portal vein if the shunting vessels responsible for the steal cannot be located and dealt with at surgery.     

Selective distal splenorenal shunt without requiring splenopancreatic disconnection with the use of the external iliac vein graft: a preliminary report.

BACKGROUND: Distal splenorenal shunt (DSRS) with splenopancreatic disconnection (SPD) is an ideal operation for permanent control of variceal bleeding. However, it is a very complicated procedure, and DSRS without SPD has a functional disadvantage: It gradually loses its selectivity and portal blood flow. To overcome these conditions, we designed a new technique--modified DSRS, which is easy to perform and maintains long-term selectivity of the shunt. METHODS: Modified DSRS was performed by using an external iliac vein graft without treating small pancreatic tributaries of the splenic vein. It was applied in 4 cases, and shunt patency and selectivity were examined by angiography during follow-up periods (6-76 months). RESULTS: Modified DSRS was technically more feasible and less complicated than DSRS with SPD. Every attempt was successful. There was no operative mortality, and all the patients were discharged from the hospital in good condition. The shunts were patent in all of them, and the selectivity of the shunt was maintained better in comparison to standard DSRS. CONCLUSIONS: Modified DSRS is a much easier and safer technique than standard DSRS. We consider this procedure to be the best method for surgical management of portal hypertension causing esophageal and gastric varices.     

Ligation of left renal vein for large spontaneous splenorenal shunt to prevent portal flow steal in adult living donor liver transplantation

Persistance of a large spontaneous splenorenal shunt (SRS) may result in graft failure in adult living donor liver transplantation (LDLT) because it reduces the effective portal perfusion to the partial liver graft by diversion of hepatotrophic portal flow into this hepatofugal pathway. We performed a prospective study to evaluate the efficacy of ligation of left renal vein (LRV) to prevent portal flow steal and the safety of this procedure to the renal function in adult LDLT patients with SRS. Between October 2001 and January 2005, 44 cirrhotic patients with large SRS underwent LDLT with ligation of LRV. Each patient received pre- and postoperative computed tomography and Doppler USG to assess the changes of collaterals and portal flow, as well as serial renal and liver function tests. Portal flow after ligation of LRV was statistically and significantly increased when compared with pre-operative value (P = 0.001). Whereas four patients (9.1%) demonstrated sustained, elevated serum creatinine levels after operation, the renal function tests returned to normal in 40 patients. All patients recovered with satisfactory regeneration of the partial liver graft and there was no procedure-related permanent renal dysfunction. In conclusion, ligation of LRV to prevent a 'portal steal phenomenon' seems to be a safe and effective graft salvage procedure for large spontaneous SRS (>10-mm diameter) in adult LDLT.     

Absence of the left portal vein: a difficulty for reduction of liver grafts?

BACKGROUND: Absence of the portal bifurcation is exceptional and characterized by an absent extrahepatic portal vein bifurcation, the right portal vein only being at the porta hepatis. There is no extraparenchymal left portal vein. This may represent a problem in liver splitting, reduction, and living related transplantation. METHOD: A case was encountered during reduction of a cadaveric liver allograft to a left lateral segmental graft from a 40-kg cadaveric donor to a 15-kg recipient. The portal venous inflow was reconstructed with a vein graft via a novel extrahilar approach to the left portal vein at the umbilical fissure. RESULTS: This graft was used successfully in a 3-year-old child requiring transplantation for a failed Kasai operation for extrahepatic biliary atresia. The child is now well, 1 year posttransplant, after an uneventful postoperative course with good portal flow within the graft. CONCLUSION: The situation of an absent left portal vein extrahepatic course should not preclude splitting or reduction procedures. The innovative technical solution, we propose, should add to the armamentarium of the liver transplant surgeon contemplating a left lateral segmental graft for the paediatric liver transplant recipient.     

Living-related liver transplantation with renoportal anastomosis for a patient with large spontaneous splenorenal collateral

BACKGROUND: A large splenorenal collateral must be interrupted during liver transplantation to secure adequate portal perfusion. However, this process increases the complexity of the operative procedure and may cause hazardous bleeding. Recently, renoportal anastomosis in portal reconstruction was reported in cadaveric liver transplantation for patients with surgically created splenorenal shunts. We used this technique in a living-related liver transplantation. METHODS: A 29-year-old female with a large spontaneous splenorenal collateral and a portal venous thrombus underwent a living-related liver transplantation. At surgery, the left renal vein was divided and the distal stump was anastomosed to the portal vein of the graft without interrupting collaterals. RESULTS: Adequate portal venous blood flow was maintained throughout the postoperative course. The patient was discharged 9 weeks after transplantation and remains well. CONCLUSION: The renoportal anastomosis could be used for portal reconstruction in living-related liver transplantation for patients with a large splenorenal collateral. It provides adequate portal perfusion without interrupting collateral circulation.     

Opening of a foramen ovale during liver transplantation. The value of transesophageal echocardiography

A case is reported of a foramen ovale becoming patent during orthotopic liver transplantation (OLT). The patient had a hepatoma secondary to post-hepatitis cirrhosis. Monitoring included transesophageal echocardiography (TEE). A veno-venous shunt between the right femoral, portal and left axillary veins was used so as to maintain the venous return during portal and caval clamping. The patient's haemodynamic state remained quite stable throughout this period, and no vasoactive drug was required. Five min after graft reperfusion, pulmonary arterial pressure increased suddenly (mean PAP: 27 mmHg). TEE revealed paradoxical movements of the atrial septum. Colour coded Doppler ultrasound showed blood flowing from the right to the left atrium through a patent foramen ovale. Fifteen min later, mean PAP decreased (18 mmHg) and TEE no longer showed any flow between the two atria. Several studies have reported transient pulmonary hypertension after unclamping when the donor liver is reperfused. This could induce right ventricular failure, with transient inversion of the atrial pressure gradient, which, in turn, could result in a right-to-left shunt through a patent foramen ovale. TEE can monitor regional and overall left ventricular function as well as the atrial septum. This technique might therefore to be useful for cardiac monitoring during OLT.     

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.