Portal vein thrombosis in liver transplantation

In the initial experience of liver transplantation, complete thrombosis and portal vein occlusion were considered to be absolute contraindications for liver transplantation. The incidence of portal thrombosis in patients being prepared for transplantation varies between 5% and 15% according to published series. There are 2 surgical techniques to solve absent or low portal vein flow due to thrombosis. The most widely used technique is thrombectomy and the second technique is insertion of a shunt with a venous graft in the permeable portion of the superior mesenteric vein or in a vein in the splanchnic territory. Portal thrombosis recurrence rates vary among series, ranging from 0% to 25% or even 30%, depending on its extension and severity and also on time the transplantation was performed. Although overall survival is somewhat lower, there are no significant differences in most of the series when patients with portal thrombosis who underwent transplantation are compared with those without.     

Superior mesenteric vein inflow for liver transplantation when the portal vein is occluded

An alternative solution to the problem of liver transplantation in the patient with an occluded portal vein is described. It uses a bridge graft of donor iliac vein from the superior mesenteric vein at the base of the colonic mesentery. The graft is tunnelled over the pancreas and under the stomach to the region of the liver hilum to provide portal inflow. This procedure was employed successfully in four patients, with patency for more than 2 years in the patient with the longest follow-up. By this approach it is routinely possible to perform a transplant procedure in a recipient with an occluded portal vein.     

肝移植中门静脉血栓形成的处理

目的：探讨肝移植术中门静脉血栓形成的处理方法并评价其对肝移植疗效的影响。方法：回顾性分析246例良性终末期肝病行肝移植的临床资料，并结合文献进行讨论。结果：31例（12．6％）病人术中确认有门静脉血栓形成。其中14例I级；8例Ⅱ级；7例Ⅲ级；2例Ⅳ级。I、Ⅱ级的门静脉血栓病人施行了血栓切除或取栓术：Ⅲ级血栓病人采取供者髂静脉在供肝门静脉与受者肠系膜上静脉间架桥的方式重建供肝门静脉循环：对Ⅳ级血栓，采用了改良的门腔静脉半转流术。病人术后6个月死亡率：门静脉血栓组6．5％，无门静脉血栓组7．4％（P＞0．05）。结论：术前存在的门静脉血栓已非肝移植的绝对禁忌证，根据血栓的不同情况采取合理的手术方式可以使病人获得良好的治疗效果。     

Outcomes of liver transplantation in candidates with portal vein thrombosis

Objective

The objective of the present study was to analyze the incidence of portal vein thrombosis (PVT), comparing morbidity and mortality rates among those affected with and those free of this complication. In the PVT group, we also analyzed mortality related to partial (PPVT) and total (TPVT) thrombosis.

Methods

We undertook a retrospective study of orthotopic liver transplantations from deceased donors in 617 recipients from January 1991 until October 2008. Recipients were classified according to whether they had PVT. In all cases, we considered age, sex, Model for End-stage Liver Disease score, Child-Pugh score, indication for transplantation, type of thrombosis, surgical technique blood product transfusion, and survival rate.

Results

There were 48 patients with PVT (7.78%) among 670 transplantations in 617 recipients in our institution. Concerning the type of thrombosis, 28 (58.3%) were partial and 20 (41.7%) total with complete occlusion of the portal vein lumen.

Conclusion

PVT in liver transplant candidates is a rare event (7.8%) that entails greater difficulty in the procedure, expressed as a longer operative time, greater consumption of blood products, and complex surgical techniques. The prognosis for these patients depends on the type of thrombosis: patients with TPVT showed a higher mortality, whereas those with PPVT had survival rates comparable to those of candidates with a permeable portal vein.     

肝移植治疗终末期肝病合并门静脉血栓的临床研究

目的 总结分析肝移植中门静脉血栓(PVT)的处理经验以及PVT对肝移植术后疗效的影响.方法 总结1995年5月至2007年9月194例接受肝移植手术的患者的临床资料,其中术前存在PVT 24例(12.4%),Ⅰ级12例、Ⅱ级9例、Ⅲ级2例、Ⅳ级1例.根据血栓程度分级采取不同的方式进行门静脉重建.术后根据凝血酶原时间(PT),应用普通肝素或低分子肝素预防性抗凝.术后应用多普勒超声监测门静脉血供.选取同期接受肝移植手术的无PVT的170例患者作为对照组,比较两组手术过程和预后的差别.结果 21例Ⅰ级、Ⅱ级血栓患者行血栓切除术,2例Ⅲ级血栓患者行髂静脉-肠系膜上静脉搭桥,1例Ⅳ级血栓患者将供肝门静脉和受者粗大的门静脉属支吻合.有PVT组比无PVT组手术时间和住院时间长,输血量多,术后PVT的再发率高(P<0.05),但并发症发生率、围手术期病死率和术后1年生存率两组间无差别(P>0.05).PVT组有2例术后血栓再发,经放射介入治疗治愈.结论 术前PVT的存在增加了肝移植手术的难度和术后PVT的再发率,但对肝移植的预后没有影响.     

Portal vein arterialization for liver transplantation with extensive portomesenteric vein thrombosis: a case report

We report herein a case of extensive thrombosis of portal venous system including mesenteric vein in a 70-year-old man who suffered from end-stage post-hepatitis C cirrhosis and who underwent orthotopic liver transplantation. There was no way to divert portal blood flow to the new liver because such an extensive thrombosis of portomesenteric venous system. There are some case reports of portocaval hemitransposition with some success but high mortality. We decided to arterialize the portal vein of the liver allograft with the recipient hepatic artery and the donor hepatic artery was anastomosed to the supraceliac aorta. He recovered slowly from the operation. At 1 year after the transplantation, he is doing well with perfect liver function tests. This case challenges our belief that portal blood flow is essential for the liver because of hepatotrophic factors.     

肝移植术中复杂门静脉机化血栓的处理

目的：探讨存在复杂门静脉机化血栓者肝移植术中门静脉的处理要点。方法：为17例机化血栓超过门静脉内径50％的患者施行肝移植，术中9例在切除血栓段门静脉或取栓后，将受者的门静脉与供肝门静脉行端端吻合；5例将供肝门静脉与受者的曲张冠状静脉行端侧吻合；1例切除闭塞段门静脉，利用供者的髂静脉于供肝门静脉与受者肠系膜上静脉间搭桥；1例供肝门静脉与受者的胆总管前曲张静脉行端侧吻合；1例采用供者的髂静脉在供肝门静脉和受者的脾门旁曲张静脉间搭桥，行端侧吻合。结果：17例患者，死亡2例，1例死于感染，1例死于肝动脉出血，但此2例患者的门静脉血流一直通畅。存活的15例随访2～12个月，其中1例术后因门静脉血流量不足，而行二次肝移植，在缝扎分流的侧支后，门静脉血流恢复正常，其他患者的门静脉血流均通畅。结论：存在复杂门静脉机化血栓时首选栓塞段门静脉切除或取栓后门静脉重建，不能取栓或取栓后血流量不足时，可改行供肝门静脉与受者曲张内脏静脉的端侧吻合，也可取得较好效果。     

肝移植中门静脉血栓的处理经验

目的 探讨肝移植术中门静脉血栓的几种处理方法及其疗效.方法 回顾性分析773例次肝移植临床资料.773例中,107例病人有门静脉血栓,其中59例Ⅰ级;33例Ⅱ级;12例Ⅲ级;3例Ⅳ级.Ⅰ、Ⅱ级组行血栓切除或取栓术;Ⅲ级采用取栓术或肠系膜上静脉架桥的方式重建供肝门静脉;对Ⅳ级采用改良门腔静脉半转位术和门静脉胃冠状静脉吻合重建供肝门静脉.结果 Ⅰ、Ⅱ级组移植肝功能恢复良好,围手术期病死率为4.3%.Ⅲ级取栓组5例肝功能恢复良好,围手术期无死亡.静脉架桥组7例中有2例肝功能恢复不佳,围手术期病死率为28.6%.Ⅳ级组肝功能恢复良好,围手术期无死亡.结论 门静脉血栓已非肝移植禁忌证,根据血栓的不同情况采取合理的手术方式重建门脉系统可以获得良好的治疗效果.     

外翻式门静脉血栓切除术在肝移植术中的应用

目的 探讨肝移植术中门静脉血栓切除技术的改进.方法 回顾性分析天津市第一中心医院移植外科收治的合并门静脉血栓(PVT)的198例肝移植患者的临床资料,根据术中PVT的处理方法不同分为两组:A组为常规外翻式门静脉血栓切除术组(n=43),B组为不切断PVT的外翻式门静脉血栓切除术组(n=155).分别比较两组患者术中一般情况、失血量、血栓切除成功率、PVT复发率及患者生存情况等指标.结果 两组手术时间无明显差异(P>0.05).两组Yerdel Ⅰ级及Ⅱ级患者血栓切除成功率均为100%;B组中Yerdel Ⅲ级患者血栓切除成功率较A组高(100%比45.4%;X~2=12.38,P<0.01).B组失血量较A组明显减少[(4315.4±630.5)ml比(3509.2±862.7)ml,P<0.05].B组Yerdel Ⅰ～Ⅱ级PVT患者术后血栓复发率与A组相比差异无统计学意义(P>0.05),而Yerdel Ⅲ级患者术后血栓复发率低于A组(5.6%比2/5;X~2=4.09,P<0.05);两组Yerdel Ⅰ～Ⅲ级PVT患者围手术期病死率均为0,差异无统计学意义(P>0.05).两组YerdelⅠ～Ⅲ级PVT患者1年生存率的差异无统计学意义(86.5%比89.O%,P>0.05).结论 不切断PVT的外翻式门静脉血栓切除术可以简化手术操作,减少术中出血量,扩大应用范围,提高血栓切除的成功率,降低术后血栓复发率.     

Eversion thromboendovenectomy for organized portal vein thrombosis encountered during liver transplantation

INTRODUCTION: Due to the technical experience acquired in the field of liver transplantation portal vein thrombosis is no longer considered a contraindication for transplantation. Nevertheless, the results obtained in patients with portal vein thrombosis are at times suboptimal, and there is no consensus on the appropriate surgical technique. PATIENTS AND METHODS: Among the 455 liver transplants performed between May 1988 and December 2001, 32 (7%) presented with portal vein thrombosis. Twenty (62%) were type Ib, seven (22%) type II/III, and five (16%) type IV. Twenty-two were men (69%), with a mean age of 50 years (range: 30-70 years); the thrombosis in all cases developed in a cirrhotic liver. The surgical method in all cases consisted of an eversion thromboendovenectomy under direct visual guidance, with occlusion of the portal flow using a Fogarty balloon. RESULTS: Among the 32 cases undergoing thrombectomy, 31 (96%) were successful with a failure in a case of type IV thrombosis, which was resolved by portal arterialization. Of the 31 successful cases, only one with type IV thrombosis rethrombosed. The 5-year survival rate of the patients in the series was 69%. Only two patients died from causes related to the thrombosis, both showing type IV thrombosis. CONCLUSION: The ideal treatment for portal thrombosis during liver transplantation depends on its extension and on the experience of the surgeon. In our experience, eversion thromboendovenectomy resolves most thromboses (types I, II, and III), but management of type IV, which occasionally can be treated with this technique, may require more complex procedures such as bypass, portal arterialization or cavoportal hemitransposition.     

门静脉血栓的肝移植术中处理

目的 探讨门静脉血栓(PVT)的肝移植术中外科处理方法及其效果.方法 肝移植患者2508例,共行肝移植2614次,其中253例术前并发PVT.并发PVT者的Yerdel分级为,Ⅰ级者104例,Ⅱ级者114例,Ⅲ级者29例,Ⅳ级者6例.根据具体情况对并发Ⅰ、Ⅱ级PVT者施行静脉血栓切除术、外翻血栓切除术或外翻式门静脉内膜剥脱切除术;并发Ⅲ级PVT者,18例行外翻式门静脉内膜剥脱切除术,11例行外翻血栓切除术;并发Ⅳ级PVT者行外翻式门静脉内膜剥脱切除术.结果 218例并发Ⅰ、Ⅱ级PVT者中,32例行静脉血栓切除术,52例行外翻血栓切除术,134例行外翻式门静脉内膜剥脱切除术,均获得成功.29例并发Ⅲ级PVT者中,18例行外翻式门静脉内膜剥脱切除术,均获得成功;11例行外翻血栓切除术,其中5例获得成功,6例失败.6例并发Ⅳ级PVT者中,3例行外翻式门静脉内膜剥脱切除术,获得成功,3例取栓失败.253例并发PVT者肝移植术后6个月的存活率为93.7%,与同期无PVT的肝移植患者相比较(94.4%),差异无统计学意义(P>0.05).结论 并发PVT者可接受肝移植,术中应根据PVT的Yerdel分级情况,采取适合的外科处理方式.