Specific vascular complications of orthotopic liver transplantation with preservation of the retrohepatic vena cava: review of 1361 cases

Post-operative imaging in liver transplantation: State-of-the-art and future perspectives

Orthotopic liver transplantation (OLT) represents a major treatment for end-stage chronic liver disease, as well as selected cases of hepatocellular carcinoma and acute liver failure. The ever-increasing development of imaging modalities significantly contributed, over the last decades, to the management of recipients both in the pre-operative and post-operative period, thus impacting on graft and patients survival. When properly used, imaging modalities such as ultrasound, multidetector computed tomography, magnetic resonance imaging (MRI) and procedures of direct cholangiography are capable to provide rapid and reliable recognition and treatment of vascular and biliary complications occurring after OLT. Less defined is the role for imaging in assessing primary graft dysfunction (including rejection) or chronic allograft disease after OLT, e.g., hepatitis C virus (HCV) recurrence. This paper: (1) describes specific characteristic of the above imaging modalities and the rationale for their use in clinical practice; (2) illustrates main imaging findings related to post-OLT complications in adult patients; and (3) reviews future perspectives emerging in the surveillance of recipients with HCV recurrence, with special emphasis on MRI.

Hepatic venous outflow obstruction after transplantation: outcomes for treatment with self-expanding stents

OBJECTIVES

To evaluate the safety and patency of self-expanding stents to treat hepatic venous outflow obstruction after orthotopic liver transplantation. To evaluate differences in the response between patients with early obstruction and patients with late obstruction.

MATERIAL AND METHODS

This is a retrospective analysis of 16 patients with hepatic venous outflow obstruction after liver transplantation treated with stents (1996-2011). Follow-up included venography/manometry, ultrasonography, CT, and laboratory tests. We did a descriptive statistical analysis of the survival of patients and stents, technical and clinical success of the procedure, recurrence of obstruction, and complications of the procedure. We also did an inferential statistical analysis of the differences between patients with early and late obstruction.

RESULTS

The mean follow-up period was 3.34 years (21-5,331 days). The technical success rate was 93.7%, and the clinical success rate was 81.2%. The rate of complications was 25%. The survival rates were 87.5% for patients and 92.5% for stents. The rate of recurrence was 12.5%. The rate of primary patency was 0.96 (95% CI 0.91-1) at 3 months, 0.96 (95% CI 0.91-1) at 6 months, 0.87 (95% CI 0.73-1) at 12 months, and 0.87 (95% CI 0.73-1) at 60 months. There were no significant differences between patients with early and late obstruction, although there was a trend toward higher rates of primary patency in patients with early obstruction (P=.091).

CONCLUSIONS

Treating hepatic venous outflow obstruction after orthotopic transplantation with self-expanding stents is effective, durable, and effective. There are no significant differences between patients with early obstruction and those with late obstruction.

Imaging of vascular complications and their consequences following transplantation in the abdomen

Transplantation is the surgical treatment of choice for end-stage organ failure. Transplantation procedures performed in the abdomen include liver, renal, pancreas, islet, intestinal, and multivisceral transplantations. Imaging plays a pivotal role in the posttransplantation setting for monitoring the transplant allograft and screening for complications. Knowledge of the surgical techniques employed in abdominal transplantation is essential because it facilitates radiologic understanding and interpretation of the posttransplantation anatomy. This article includes a basic description of the standard surgical techniques performed in the abdomen, with emphasis on the relevant vascular anastomotic reconstructions used. Posttransplantation complications can be broadly classified as vascular or nonvascular in origin. Many of these complications can be accurately depicted and characterized at imaging and dealt with definitively by using interventional radiology techniques, which can be graft- and life-saving and can obviate further complex surgical intervention. The article discusses imaging appearances of vascular complications and their consequences after transplantation in the abdomen. These vascular complications include arterial thrombosis, arterial stenosis, venous thrombosis and stenosis, arteriovenous fistula formation, and pseudoaneurysm formation. The relevant predisposing factors, clinical features, imaging appearances, and potential treatment options for vascular complications of various types of transplantation are presented in a logical and integrated fashion. Knowledge and imaging recognition of the posttransplantation vascular complications discussed in this article will aid radiologists in accurate imaging characterization and thereby facilitate appropriate clinical management and therapy.

Endovascular treatment with primary stenting of inferior cava vein torsion following orthotopic liver transplantation with modified piggyback technique

PURPOSE

This study was undertaken to evaluate primary stenting in patients with inferior vena cava torsion after orthotopic liver transplantation performed with modified piggyback technique.

MATERIALS AND METHODS

From November 2003 to October 2010, six patients developed clinical, laboratory and imaging findings suggestive of caval stenosis, after a mean period of 21 days from an orthotopic liver transplantation performed with modified piggyback technique. Vena cavography showed stenosis due to torsion of the inferior vena cava at the anastomoses and a significant caval venous pressure gradient. All patients were treated with primary stenting followed by in-stent angioplasty in three cases.

RESULTS

In all patients, the stents were successfully positioned at the caval anastomosis and the venous gradient pressure fell from a mean value of 10 to 2 mmHg. Signs and symptoms resolved in all six patients. One patient died 3 months after stent placement due to biliary complications. No evidence of recurrence or complications was noted during the follow-up (mean 49 months).

CONCLUSIONS

Primary stenting of inferior vena cava stenosis due to torsion of the anastomoses in patients receiving orthotopic liver transplantation with modified piggyback technique is a safe, effective and durable treatment.

Successful percutaneous transluminal balloon dilatation for hepatic venous outflow obstruction after pediatric liver transplantation: A series of cases

AIM

Whether percutaneous transluminal balloon dilatation (PTBD) or stent placement should be used in children with hepatic venous outflow obstruction (HVOO) is still controversial. The aim of the present study was to retrospectively describe experience in diagnosis and treatment of HVOO and to evaluate the outcome of PTBD in HVOO patients after pediatric liver transplantation (P-LT).

METHODS

From January 2001 to January 2011, 54 children received P-LT at our center. The clinical features of children with HVOO analyzed included demography, type of donor and liver transplant, the new-onset symptoms, liver function test, interventional examination, and treatment and outcome.

RESULTS

Three children were treated successfully with PTBD without stenting. All patients received percutaneous interventional management successfully. In the total of eight episodes of PTBD across the stenosis, the mean pressure gradient ± standard deviation was 16.6 ± 7.90 mmHg before PTBD and 6.8 ± 2.27 mmHg after PTBD. The difference was significant (P < 0.05). All of the three HVOO patients were still surviving with primary graft functioning normally until the last follow up.

CONCLUSION

HVOO after P-LT should be taken seriously. PTBD is an effective and safe treatment for HVOO in younger patients subjected to P-LT and re-venoplasty is recommended even in patients with recurrent HVOO.

Long-term outcome of percutaneous interventions for hepatic venous outflow obstruction after pediatric living donor liver transplantation: experience from a single institute

PURPOSE

To evaluate retrospectively the long-term outcome of percutaneous interventions for hepatic venous outflow obstruction (HVOO) occurring after pediatric living donor liver transplantation (LDLT).

MATERIALS AND METHODS

Between October 1997 and December 2012, 48 patients (24 boys, 24 girls; median age, 6 y) who had undergone LDLT were confirmed to have HVOO using percutaneous hepatic venography and manometry. All patients underwent percutaneous interventions, including balloon angioplasty with or without stent placement. Technical success, clinical success, patency rates, stent placement, and major complications were evaluated.

RESULTS

Technical success was achieved in 92 of 93 sessions (99.0%) and in 47 of 48 patients (97.9%), and clinical success was achieved in 41 of 48 patients (85.4%). During the follow-up period (range, 1-182 mo; median, 51.5 mo), 28 patients were treated with a single session of balloon angioplasty, and 20 patients who developed recurrent stenosis were treated with repeated percutaneous interventions. The rates of primary and primary-assisted patency at 1, 3, 5, and 10 years after balloon angioplasty were 64%, 57%, 57%, and 52% (primary patency) and 98%, 95%, 95%, and 95% (primary-assisted patency). Of six patients with stent placement, four had no recurrent HVOO after the stent placement, but two developed recurrent stenosis. The stent migrated to the right atrium in one patient.

CONCLUSIONS

Percutaneous interventions were effective treatments for HVOO after LDLT.

Radiologic assessment of hepatobiliary surgical complications

The complexity of hepatobiliary procedures continues to evolve at a rapid rate, with an increasing number of living donor liver transplants and extensive cancer resections being performed. The associated complications are a significant cause of morbidity and mortality, and are often complex injuries, involving both vascular and biliary structures. In this paper we describe the complications associated with laparoscopic cholecystectomy, liver transplant surgery, and hepatic resection. Focus is on the classical imaging appearances, imaging modality options, and varying management strategies for these injuries, to show how the radiologist's role is vital in ensuring the correct diagnosis is made and the appropriate treatment is instigated.

Successful recanalization of occluded intrahepatic inferior vena cava in post-liver transplant Budd-Chiari syndrome

Budd-Chiari syndrome following a liver transplant is an uncommon phenomenon. We present a case of endovascular management of a focal circumferential inferior vena cava (IVC) occlusion at the anastomosis that developed 10 years after orthotopic liver transplantation. It was successfully recanalized using the stiff end of the guidewire and percutaneous transluminal angioplasty with a high-pressure balloon. During a 14-month follow up, the IVC remained patent and did not require further intervention.

Liver transplantation with piggyback anastomosis using a linear stapler: a case report

The so-called piggyback technique of liver transplantation (PB-LT) preserves the recipient's caval vein, shortening the warm ischemic time. It can be reduced even further by using a linear stapler for the cavocaval anastomosis. Herein, we have presented a case of a patient undergoing a side-to-side, whole-organ PB-LT for cryptogenic cirrhosis. Upper and lower orifices of the donor caval vein were closed at the back table using a running 5-0 polypropylene suture. Three stay sutures were then placed on caudal parts of both the recipient and donor caval with a 5-mm venotomies. The endoscopic linear stapler was placed upward through the orifices and fired. A second stapler was placed more cranially and fired resulting in a 8-9 cm long cavocavostomy. Some loose clips were flushed away from the caval lumen. The caval anastomosis was performed within 4 minutes; the time needed to close the caval vein stapler insertion orifices (4-0 polypropylene running suture) before reperfusion was 1 minute. All other anastomoses were performed as typically sutured. The presented technique enables one to reduce the warm ischemic time, which can be of particular importance with marginal grafts.

"Passing loop" technique: a new modification of the piggyback technique tailored to voluminous liver grafts--case report

BACKGROUND

The modified piggyback technique with side-to-side cavocavostomy decreases the risk of outflow obstruction compared with the standard piggyback method. However, this modification is not ideal for recipients who receive a graft that is voluminous or bears an enlarged caudate lobe.

METHODS

We modified the inferior vena cava (IVC) preservation technique against deleterious complications of compression by using a passing loop.

CASE PRESENTATION

A 49-year-old woman, who underwent orthotopic liver transplantation for hepatic failure, was allocated a large-size liver. In anticipation of serious caval compression due to the voluminous grafts, we kept the suprahepatic or infrahepatic donor caval cuffs open for an anastomosis. The first anastomosis was performed between suprahepatic donor IVC cuff and recipient middle-left hepatic vein common channel; the second anastomosis was a terminolateral cavocavostomy between infrahepatic donor IVC cuff and the anterior wall of the recipient's IVC.

DISCUSSION

When the liver circulation was restored, the donor retrohepatic vena cava served as a passing loop for both hepatic venous outflow and infra-diaphragmatic venous return to bypass possible IVC compression. Our technique may solve a dilemna for patients receiving voluminous liver grafts.

Liver retransplantation for adult recipients

Living donor liver graft can be used for the first or second liver transplantation. The timing of retransplantation also should be stratified as 2 types according to the reoperation timing. Combination of these two classifications results in 6 types of living donor liver transplantation (LDLT)-associated retransplantation. However, late retransplantation to LDLT might have not been performed in most LDLT programs, thus other 4 types of LDLT-associated retransplantation can be taken into account. The most typical type of LDLT-associated retransplantation might be early living donor-to-deceased donor retransplantation. For early living donor-to-living donor retransplantation, its eligibility criteria might be similar to those of early living donor-to-deceased donor retransplantation. For early deceased donor-to-living donor retransplantation, its indications are exactly the same to those for aforementioned living donor-to-living donor retransplantation. Late deceased donor retransplantation after initial LDLT has the same indication for ordinary late deceased donor retransplantation.

Side-to-side cavocavostomy in adult piggyback liver transplantation

OBJECTIVE

Our objective was to perform a retrospective study that described the anastomosis technique as well as the complications of side-to-side cavo-caval reconstruction.

PATIENTS AND METHODS

From June 1998 to April 2011, we performed 284 liver transplantations including 10 adults with live donor organs. In all cases but 2 (272), cavo-caval reconstruction was performed using side-to-side cavo-caval (STSCC) anastomosis. In 19 cases (6.9%), we also carried out an end-to-side temporary porto-caval shunt (TPCS). In 17 cases (6.2%) the technique was performed for retransplantation.

RESULTS

STSCC anastomosis was technically feasible in all but 2 cases, regardless of the recipient's vena cava, anatomic factors, or graft size. Mean operative time for the STSCC was 13 minutes (range, 6-25). Routine Doppler ultrasonography was performed intraoperatively at the end of the surgery. There was no case of cava stump thrombosis. Complications associated with this technique were limited to 2 patients. One complication was torsion due to donor graft/recipient mismatch, which was successfully treated surgically by falciform ligament fixation. The second complication was only evident by sinusoidal congestion and was managed nonoperatively. Seventeen cases were uneventful for retransplant recipients.

CONCLUSIONS

STSCC during piggyback liver transplantation is safe and can be performed in the retransplantation setting, with a low incidence of venous outflow obstruction that can be associated with the traditional piggyback technique. Our data suggest that donor graft to recipient mismatch is not an absolute contraindication when proper body size match is considered. A wide anastomosis with typical recipient hepatic vein inclusion is warranted with routine postanastomotic Doppler ultrasonography.

Hepatic veins anatomy and piggy-back liver transplantation

BACKGROUND

The piggy-back caval anastomosis technique is widely used in orthotopic liver transplantation although it carries an increased risk of complications, including outflow obstruction and Budd-Chiari syndrome. The aim of this study is to clarify the anatomy and variations of hepatic veins (HVs) draining into the inferior vena cava (IVC), and to classify the surgical techniques of piggy-back liver transplantation (PBLT) based on the anatomy of HVs which can reduce the occurrence of complications.

METHODS

PBLT was performed in 248 consecutive cases at our hospital from January 2004 to August 2011. The anatomy of recipients' HVs was determined when removing the native diseased livers. Both anatomy of HVs and short HVs draining into the IVC were recorded. These data were collected and analyzed.

RESULTS

We classified anatomic variations of HVs in the 248 livers into five types according to the way of drainage into the IVC: type I (trunk type of left and middle HVs), 142 (57.3%) patients; type II (trunk type of right and middle HVs), 54 (21.8%); type III (trunk type of left, middle and right HVs), 14 (5.6%); type IV (non-trunk type of left, middle and right HVs), of which, type IVa, 16 (6.5%), in the same horizontal plane; type IVb, 18 (7.3%), in different horizontal planes; and type V (segment type), 4 (1.6%). The patients whose HVs anatomy belonged to types I, II and III underwent classical piggy-back liver transplantation. Type IVa patients had classical PBLT via HV venoplasty prior to piggy-back anastomosis, while type IVb patients and type V patients could only have modified PBLT.

CONCLUSION

This study demonstrates that HVs can be classified according to the anatomy of their drainage into the IVC and we can use this classification to choose the best operative approach to PBLT.

Liver transplantation with preservation of the inferior vena cava: lessons learned through 2,000 cases

BACKGROUND

We aim to demonstrate the utility and efficacy of the "piggyback technique" (PBT); liver transplant (LT) with caval preservation.

STUDY DESIGN

Adult LTs were performed with intent to use the PBT except in cases of juxtacaval malignancy or technical difficulty. Hepatic venous outflow was established between the donor suprahepatic cava and the joined ostia of all recipient suprahepatic veins. Technical variants with the donor cava and recipient retrohepatic cava were used as needed. The experience was divided into 2 eras: E1 (1994-2002), E2 (2002-2010).

RESULTS

We completed 945 of 1080 LTs in E1 (87.5%) and 851 of 920 LTs in E2 (92.5%) using the PBT. Thirty day mortality was 4.6% in E1, 3% in E2 (p = 0.02) with 2 intra-operative deaths in E1. One, 3, 5 year patient survival was 83.7, 75.6, 69.3% in E1 vs. 86, 78.4, 73.8% in E2 (p = 0.057). Graft survival was 77.7, 69, 62.3% in E1 vs. 84, 76.2, 71.2% in E2 (p < 0.0001). Median operative time and hospital length of stay improved in E2 (p < 0.0001, 0.0001). Outflow variants were used more frequently in E2 (11.3% vs. 6.1%). Nine patients (0.5%) developed outflow obstruction, 6 in E1, and 3 in E2. Twice, it was recognized and corrected intraoperatively. Seven patients presented with refractory ascites. Six were successfully treated (4 balloon dilatation, 2 surgical revision), one patient died after attempted dilatation.

CONCLUSIONS

The PBT can be used as the preferred technique in adult LT. With experience, the technique was used more frequently, with more variants, with improved outcomes. Outflow obstruction was a rare complication.

Cavo-caval intervention stent insertion after deceased-donor liver transplantation using side-to-side piggyback technique: report of a case

Liver transplantation with preservation of the recipient vena cava (piggyback technique) has been performed as an alternative to the conventional method. Outflow disturbance or obstruction of the vena cava in the early period after liver transplantation is associated with high morbidity and mortality. We used side-to-side cavo-caval anastomosis (modified piggyback technique) in a deceased-donor liver transplantation (DDLT) for venous outflow reconstruction. On postoperative day 9, the patient developed abdominal discomfort, and abnormal liver function showing serum total bilirubin of 6.2 mg/dl and serum AST/ALT of 297/597 IU/L. Doppler ultrasound showed mono-phasic wave forms of the hepatic vein. Computed tomography showed focal narrowing of 9.5 mm×12 mm in diameter at the cavo-caval anastomosis site. Liver biopsy was showed that there was no evidence of acute allograft rejection. Direct venogram showed stenosis of the cavo-caval anastomosis with a pressure gradient of 12 mmHg. An interventional stent was inserted in the stenotic site of the inferior vena cava, and the pressure gradient decreased to 2 mmHg. He was discharged from hospital on postoperative day 23 without any other complications. Herein we report a case of deceased-donor liver transplantation using the modified piggyback technique, who received an inferior vena cava stent due to stricture of the reconstructed orifice of the vena cava.

A case-controlled study of the safety and efficacy of transjugular intrahepatic portosystemic shunts after liver transplantation

The role of transjugular intrahepatic portosystemic shunt (TIPS) insertion in managing the complications of portal hypertension is well established, but its utility in patients who have previously undergone liver transplantation is not well documented. Twenty-two orthotopic liver transplantation (OLT) patients and 44 nontransplant patients (matched controls) who underwent TIPS were analyzed. In the OLT patients, the TIPS procedure was performed at a median of 44.8 months (range = 0.3-143 months) after transplantation. Eight (36.4%) had variceal bleeding, and 14 (63.6%) had refractory ascites. The underlying liver disease was cholestatic in 10 (45.4%) and viral in 4 (18.2%). The mean pre-TIPS Model for End-Stage Liver Disease (MELD) score was 13.4 ± 5.1. There were no significant differences in age, sex, indication, etiology, or MELD score with respect to the control group. The mean initial portal pressure gradients (PPGs) were similar in the 2 groups (21.0 versus 22.4 mm Hg for the OLT patients and controls, respectively), but the final PPG was lower in the control group (9.9 versus 6.9 mm Hg, P < 0.05). The rates of both technical success and clinical success were higher in the control group versus the OLT group [95.5% versus 68.2% (P < 0.05) and 93.2% versus 77.2% (P < 0.05), respectively]. The rates of complications and post-TIPS encephalopathy were similar in the 2 groups, and there was a trend toward increased rates of shunt insufficiency in the OLT group. The mortality rate of the patients with a pre-TIPS MELD score > 15 was significantly higher in the OLT group [hazard ratio (HR) = 4.32, 95% confidence interval (CI) = 1.45-12.88, P < 0.05], but the mortality rates of the patients with a pre-TIPS MELD score < 15 were similar in the 2 groups. In the OLT group, the predictors of increased mortality were the pre-TIPS MELD score (HR = 1.161, 95% CI = 1.036-1.305, P < 0.05) and pre-TIPS MELD scores > 15 (HR = 5.846, 95% CI = 1.754-19.485, P < 0.05). In conclusion, TIPS insertion is feasible in transplant recipients, although its efficacy is lower in these patients versus control patients. Outcomes are poor for OLT recipients with a pre-TIPS MELD score > 15.

Development of an improved pig model of piggyback liver transplantation with temporary portacaval shunting

AIM: To improve the piggy-back orthotopic liver transplantation (PBOLT) technique in pigs and to enhance the survival rate of pigs after liver transplantation.

METHODS: Pigs were divided into control group and experimental group. The inferior caval vein was separated from the liver of recipients by curettage and aspiration using Peng's multifunctional operative dissector in the control group. Temporary portacaval shunting was added in the experimental group to reduce congestion in the portal system during anhepatic phase.

RESULTS: The PBOLT procedures were performed in eight pairs of pigs in both the control group and experimental group, with a success rate of 87.5% and 100%, respectively. There were significant differences in cold ischemia time (142.8 min ± 7.4 min vs 155.6 min ± 8.3 min, P = 0.006), anhepatic phase duration (25.8 min ± 1.3 min vs 36.3 min ± 1.0 min, P = 0.000), and operation time (264.1 min ± 9.5 min vs 277.3 min ± 8.6 min, P = 0.012) between the two groups though no significant difference was noted in mean bleeding volume (892.5 mL ± 113.9 mL vs 888.8 mL ± 93.7 mL, P = 0.94). The 1-, 2-, 3- and 4-day survival rates were 87.5% and 100%, 25% and 100%, 12.5% and 87.5%, and 0% and 87.5% in the control group and experimental group, respectively. On day 10 after PBOLT, 87.5% of pigs of the experimental group were still alive (P = 0.000).

CONCLUSION: PBOLT with temporary portacaval shunting can maintain hemodynamic stability and relieve congestion of the portal system in pigs during liver transplantation. Control of gastrointestinal congestion is key to the success of liver transplantation and can raise the survival rate of pigs after liver transplantation.

Successful liver transplantation for Rendu-Weber-Osler disease, a single centre experience

BACKROUNDS/PURPOSE: Hereditary hemorrhagic telangiectasia or Rendu-Weber-Osler is an autosomal dominant inherited disorder characterized by arteriovenous malformations and telangiectasia that may affect the nose, skin, lungs, brain and gastrointestinal tract. Liver involvement of the disease has been described to be responsible of biliary tract necrosis, high cardiac output and portal hypertension, due to intra-hepatic vascular shunts. We aimed to present four cases of successful orthotopic liver transplantations in this indication performing our modified Piggy-back technique.

PATIENTS AND METHODS

Between 2002 and 2008, four patients have been diagnosed for Rendu-Weber-Osler disease and underwent liver transplantation. Three of them suffered from high cardiac output with heart failure, two presented HBV infection and one patient suffered from renal failure requiring a liver-kidney transplantation. We performed our modified Piggy-back technique for liver implantation, which consists to clamp selectively the hepatic veins during the hepatectomy, without venous bypass, the retro-hepatic vena cava is preserved.

RESULTS

No hemodynamic concerns disturbed the surgery and no massive transfusions were needed. The liver replacement corrected the cardiac insufficiency due to high cardiac output for the three patients. At present, the four patients are getting well.

CONCLUSIONS

Despite new advances in immunotherapy for the medical treatment of Rendu-Weber-Osler disease, liver transplantation remains the curative option for hepatic based-hereditary hemorrhagic telangiectasia.

Piggy-back graft for liver transplantation

BACKGROUND

Piggy-back method of transplantation, which involves preservation of the recipient retrohepatic inferior vena cava, has been suggested as an alternative to the conventional method of liver transplantation, where the recipient retrohepatic inferior vena cava is resected.

OBJECTIVES

To compare the benefits and harms of piggy-back technique versus conventional liver transplantation as well as of the different modifications of piggy-back technique during liver transplantation.

SEARCH STRATEGY

We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, and Science Citation Index Expanded until June 2010 for identifying randomised trials using search strategies.

SELECTION CRITERIA

Only randomised clinical trials, irrespective of language, blinding, or publication status were considered for the review.

DATA COLLECTION AND ANALYSIS

Two authors (KSG and VP) independently identified trials and independently extracted data. We calculated the mean difference (MD) or standardised mean difference (SMD) with 95% confidence intervals (CI) using both the fixed-effect and the random-effects models with RevMan 5 based on intention-to-treat analysis for continuous outcomes. For binary outcomes, we used the Fisher's exact test since none of the comparisons of binary outcomes included more than one trial.

MAIN RESULTS

Two trials randomised in total 106 patients to piggy-back method (n = 53) versus conventional method with veno-venous bypass (n = 53). Both trials were at high risk of bias. There was no significant difference in post-operative mortality, primary graft non-function, vascular complications, renal failure, transfusion requirements, intensive therapy unit (ITU) stay, or hospital stay between the two groups. The warm ischaemic time was significantly shorter in the piggy-back method than the conventional method (MD -11.50 minutes; 95% CI -19.35 to -3.65; P < 0.01). The proportion of patients who developed chest complications were significantly higher in the the piggy-back method than the conventional method (75.8% versus 44.1%; P = 0.01).One trial randomised 80 patients to piggy-back with porto-caval bypass (n = 40) versus piggy-back without porto-caval bypass (n = 40). This trial was at high risk of bias. There was no significant difference in post-operative mortality, re-transplantation due to primary graft non-function, vascular complications, renal failure, or hospital stay between the two groups. Fewer patients required blood transfusion in the piggy-back with porto-caval bypass group (55%) than the piggy-back without porto-caval bypass group (75%) (P = 0.02). There was no significant difference in the mean amount of blood transfused between the groups (MD -1.00 unit; 95% CI -2.19 to 0.19; P = 0.10). The ITU stay was significantly shorter in the piggy-back with porto-caval bypass group (2.9 days) than the piggy-back without porto-caval bypass group (4.9 days; MD -2.00 days; 95% CI -3.82 to -0.18; P = 0.03).There were no trials comparing piggy-back method with conventional method without veno-venous bypass or different techniques of piggy-back method.

AUTHORS' CONCLUSIONS

There is currently no evidence to recommend or refute the use of piggy-back method of liver transplantation.

Hepatic venous outflow obstruction in pediatric living donor liver transplantation using left-sided lobe grafts: Kyoto University experience

The goals of this study were to evaluate the incidence of hepatic venous outflow obstruction (HVOO) in pediatric patients after living donor liver transplantation (LDLT) using left-sided lobe grafts and to assess the therapeutic modalities used for the treatment of this complication at a single center. Four hundred thirteen primary LDLT procedures were performed with left-sided lobe grafts between 1996 and 2006. All transplants identified with HVOO from a cohort of 380 grafts with survival greater than 90 days were evaluated with respect to the patient demographics, therapeutic intervention, recurrence, and outcome. Seventeen cases (4.5%) were identified with HVOO. Eight patients experienced recurrence after the initial balloon venoplasty. Two patients finally required stent placement after they experienced recurrence shortly after the initial balloon venoplasty. A univariate analysis revealed that a smaller recipient-to-donor body weight ratio and the use of reduced grafts were statistically significant risk factors. The cases with grafts with multiple hepatic veins had a higher incidence of HVOO. In conclusion, the necessity of repeated balloon venoplasty and stent placement was related to poor graft survival. Therefore, the prevention of HVOO should be a high priority in LDLT. When grafts with multiple hepatic veins and/or significant donor-recipient size mismatching are encountered, the use of a patch graft is recommended. Stent placement should be carefully considered because of the absence of data on the long-term patency of stents and stent-related complications. New stenting devices, such as drug-eluting and biodegradable stents, may be promising for the management of HVOO.

Incidence, impact, and treatment of portal and hepatic venous complications following pediatric liver transplantation: a single-center 12 year experience

PVT or PVS and HVOO are known causes of graft and patient loss after pediatric liver transplantation. Increased incidences of these complications have been reported in partial livers including DDSLT or LDLT. From 1997 to 2008, 241 consecutive pediatric patients received 271 hepatic grafts at a single center. Median follow-up is 1856 days. Surgical technique, demographics, lab values, and radiologic imaging procedures were obtained utilizing OTTR to evaluate the relationship of portal and hepatic complications with risk factors, patient and graft survival. Grafts were composed of 115/271 (42.4%) partial livers of which 90 (33.2%) were DDSLT and 25 (9.2%) LDLT. Of 271 patients, 156 (57.6%) received whole-sized grafts. There were six PVC in five patients with one patient requiring retransplantation (0.34%) and no patient deaths. Utilizing all three hepatic vein orifices on the recipient hepatic vena cava and the donor hepatic vein cut short enables a wide hepatic outflow tract unlikely to twist. None of the 241 patients developed early or late complications of the hepatic vein. None of the last 128 consecutive patients who received 144 grafts over seven and a half yr have developed either early or late complications of the hepatic or portal vein. Partial-graft actuarial survival was similar to whole-graft survival (87.2% vs. 85.3% at one yr; 76.6% vs. 80.2 at three yr; p = 0.488). Likewise, patient survival was similar between partial grafts and whole grafts (93.8% vs. 93.1% at one yr; 89.8% vs. 87.2% at three yr; p = 0.688) with median follow-up of 1822 (+/-1334) days. Patients receiving partial livers were significantly younger and smaller than patients receiving whole livers (p < 0.001). Portal and hepatic venous complications may have negative effects on patient or graft survival after pediatric liver transplantation. In our series, there was one graft and no patient loss related to portal or hepatic venous complications after pediatric liver transplantation over 12 yr.

Comparison of surgical methods in liver transplantation: retrohepatic caval resection with venovenous bypass (VVB) versus piggyback (PB) with VVB versus PB without VVB

Use of piggyback technique (PB) and elimination of venovenous bypass (VVB) have been advocated in adult liver transplantation (LT). However, individual contribution of these two modifications on clinical outcomes has not been fully investigated. We performed a retrospective review of 426 LTs within a 3-year period, when three different surgical techniques were employed per the surgeons' preference: retrohepatic caval resection with VVB (RCR+VVB) in 104 patients, PB with VVB (PB+VVB) in 148, and PB without VVB (PB-Only) in 174. The primary outcomes were intraoperative blood transfusion and the patient and graft survivals. Demographic profiles were similar, except younger recipient age in RCR+VVB and fewer number of grafts with cold ischemic time over 16 h in PB-Only. PB-Only required lesser intraoperative red blood cells (P=0.006), fresh frozen plasma (P=0.005), and cell saver return (P=0.007); had less incidence of acute renal failure (P=0.001), better patient survival (P=0.039), and graft survival (P=0.003). The benefits of PB+VVB were only found in shortened total surgical time (P=0.0001) and warm ischemic time (P=0.0001), and less incidence of acute renal failure (P=0.001) than RCR+VVB. PB-Only method seemed to provide the best clinical outcome. The benefit of PB was not fully achieved when it was used with VVB.

Vascular complications following adult piggyback liver transplantation with end-to-side cavo-cavostomy: a single-center experience

BACKGROUND

Vascular complications remain a significant cause of morbidity, graft loss, and mortality following orthotopic liver transplantation (OLT). These problems predominantly include hepatic artery and portal vein thrombosis or stenosis. Venous outflow obstruction may be specifically related to the technique of piggyback OLT.

MATERIALS AND METHODS

Between February 2002 and February 2009, we performed 200 piggyback OLT in 190 recipients. A temporary portacaval shunt was created in 44 (22%) cases, whereas end-to-side cavo-cavostomy was routinely performed for graft implantation. Pre-existent partial portal or superior mesenteric vein thrombosis was present in 17 (12%) cirrhotics in whom we successfully performed eversion thrombectomy, which was followed by a typical end-to-end portal anastomosis. The donor hepatic artery was anastomosed to the recipient aorta via an iliac interposition graft in 31 (16%) patients.

RESULTS

The 14 (7%) vascular complications included hepatic artery thrombosis (n = 5), hepatic artery stenosis (n = 3), aortic/celiac trunk rupture (n = 2), portal vein stenosis (n = 2), and isolated left and middle hepatic venous outflow obstruction (n = 1). There was also 1 case of arterial steal syndrome via the splenic artery. No patient experienced portal or mesenteric vein thrombosis. Therapeutic modalities included re-OLT, arterial/aortic reconstruction and splenic artery ligation. Vascular complications resulted in death of 5 (36%) patients.

CONCLUSION

Our experience indicated that piggyback OLT with an end-to-side cavo-cavostomy showed a low risk of venous outflow obstruction. Partial portal or mesenteric vein thrombosis is no longer an obstacle to OLT; it can be successfully managed with the eversion thrombectomy technique.

Four hundred and twenty-three consecutive adults piggy-back liver transplantations with the three suprahepatic veins: was the portal systemic shunt required?

BACKGROUND AND AIMS

The aim of this study is to analyze a single-center experience in orthotopic liver transplantation with the piggy-back technique (PB) realized with a cuff of three veins without temporary portacaval shunt. Outcome parameters were graft and patient survival and the surgical complications.

METHODS

The records of 423 liver transplantation in 396 adult recipients were reviewed. PB was performed in all cases also in patients with transjugular intrahepatic portosystemic shunts and redo transplants without temporary portacaval shunt. No hemodynamic instability was observed during venous reconstruction.

RESULTS

Operation time, cold ischemia time and anhepatic phase were, respectively, 316, 606 and 82 min, respectively. The mean intraoperative transfusion of packed red blood cells was 3.2 (range 1-48). Surgical complications were observed in 25% of the orthotopic liver transplantation and 2% of these was related to caval anastomosis. No case of caval thrombosis was observed; a stenosis was noted in seven patients, always treated with an endovascular approach. A postoperative ascites was observed in seven cases. Retransplantation was required in 6.3% patients. Overall in-hospital mortality was 5.3%, but no patient died through technical problems or complications related to PB procedure. One-, 3- and 5-year grafts and patients were 94%, 83% and 75%, and 92%, 86% and 79%, respectively.

CONCLUSION

This experience indicates that our approach is feasible with a low specific risk and can be performed without portacaval shunt, with minimal outflow venous complications.

Simplifying hepatic venous outflow reconstruction in sequential living donor liver transplantation

The native liver of a familial amyloidotic polyneuropathy recipient who undergoes living donor liver transplantation used as a graft for sequential liver transplantation does not include the inferior vena cava. Implantation of this whole liver graft to a second recipient could be simplified by borrowing the experience from right liver living donor liver transplantation. With careful release of the hepatic vein from its surrounding adventitia mainly by sharp dissections, adequate lengths of these veins could be attained without compromising the native inferior vena cava. Following venoplasty of the right and middle/left hepatic vein stumps, the single cuff of the hepatic veins is anastomosed to the inferior vena cava without interpositional venous graft or patch. Satisfactory venous outflow is reliably achieved because this is the most direct outflow tract.

Feasibility and midterm outcomes of percutaneous transhepatic balloon angioplasty for symptomatic Budd-Chiari syndrome secondary to hepatic venous obstruction

OBJECTIVES

This study evaluated the feasibility and outcomes of percutaneous transhepatic balloon angioplasty (PTBA) of the hepatic vein in the management of Budd-Chiari syndrome (BCS) secondary to hepatic venous outflow obstruction.

METHODS

From September 1996 to October 2008, 101 patients (52 males, 49 females) with BCS secondary to occlusion of the hepatic veins were prospectively treated using PTBA of the hepatic vein. Average age was 31.3 years (range, 15-57 years). Nineteen had concurrent inferior vena cava (IVC) obstruction. All the patients presented with symptomatic portal hypertension. PTBA, with or without stenting, was performed after hepatovenography.

RESULTS

PTBA was successfully performed in 92 of the 101 patients. Sixty-eight patients underwent PTBA of right hepatic vein, followed by stent placement in two. PTBA was performed in 11 patients with left hepatic vein occlusion and in 13 patients with dominant accessory hepatic vein occlusion. The technical success rate was 92 of 101 (91%). Hepatic venous pressure was significantly decreased after balloon angioplasty/stenting (P < .01, paired t test). Symptoms were significantly improved in the 92 patients who had successful PTBA. Three patients had acute hepatic vein thrombosis during or after PTBA. Two patients sustained intraperitoneal bleeding from the transhepatic puncture track, and one had intrahepatic hematoma. Pulmonary embolism developed in one patient during the operation. All complications were managed nonoperatively. There were no perioperative deaths. Within 1 year, 74 of the 101 patients returned for follow-up, and 51 patients had follow-up at 2 years. The primary patency rates were 84% (62 of 74), 78% (58 of 74), and 76% (39 or 51) at 6, 12, and 24 months after PTBA, respectively. The secondary patency rates were 95% (70 of 74), 92% (68 of 74), and 84% (43 of 51) at 6, 12, and 24 months.

CONCLUSIONS

PTBA of the hepatic vein is a safe and effective treatment of BCS. It is currently the most physiologic procedure, and the risk of postoperative encephalopathy is minimized because portal flow is not diverted. Midterm outcomes are satisfactory. Further investigation of the long-term outcomes is needed.

A single-center experience of 500 liver transplants using the modified piggyback technique by Belghiti

Over the past 4 decades, the surgical techniques of liver transplantation (LTx) have permanently evolved and been modified. Among these, the modified piggyback (MPB) technique by Belghiti offers specific advantages. The objective of this study was to present our single-center experience with the MPB technique in 500 cases. Recipients' perioperative data were prospectively collected and evaluated. Postoperative and specific complications, stay in the intensive and intermediate care unit, and the mortality rate with cause of death were analyzed. Most recipients were classified as Child C (49.1%). For the patients who underwent LTx for the first time, alcoholic (23.9%) and viral (22.2%) cirrhosis and hepatocellular carcinoma (15.1%) were the prevalent indications. The overall median warm ischemia time, anastomosis duration, and operative time were 45, 108, and 320 minutes, respectively. The median intraoperative blood loss was 1500 mL. A venovenous bypass was never needed to maintain hemodynamic stability. Only in a few cases was temporary inferior vena cava clamping necessary. Most prominent surgical complications were hemorrhage, hematoma, and wound dehiscence. Renal failure occurred in 6.2% of patients. The overall median stay in the intensive and intermediate care unit was 14 days. The mortality rates within 30 and 90 days were 6.3% and 13.3%, respectively. No technique-related death occurred. The MPB technique by Belghiti is a feasible and simple LTx technique. The caval flow is preserved during the anhepatic phase, and this minimizes the need for venovenous bypass or portocaval shunt. This technique requires only 1 caval anastomosis, which is easy to perform with a short anhepatic phase. To minimize the risk of outflow obstruction, attention should be paid by doing a wide cavocavostomy cranially to the donor inferior vena cava in a door-lock manner. This technique can be applied in almost all patients undergoing LTx for the first time and liver retransplantation as well.

Infrahepatic Vena Cavocavostomy, a Modification of the Piggyback Technique for Liver Transplantation

We describe our experience with a modification of the piggyback (PB) technique for orthotopic liver transplantation in which the donor infrahepatic vena cava is used as the venous outflow tract. From May 1997 to January 2006, a total of 109 cases using this technique were performed in 101 patients. Collected data included recipient demographics and diagnosis, warm ischemia time, use of venovenous bypass or temporary portacaval shunt and complications related to the venous outflow and graft, and patient survival. Data were compared with the patients undergoing standard PB technique during the same period. The reasons for using the technique were grouped according to whether there was a problem with the recipient hepatic veins or a concern about the length or diameter of the donor suprahepatic vena cava. These included the presence of a trans-jugular intrahepatic portosystemic shunt (eight cases), retransplantation (22 cases), thin-walled, friable hepatic veins (32 cases), Budd-Chiari syndrome (two cases), domino liver procurement (six cases), reduced or split liver grafts (five cases), and graft inferior vena cava to recipient hepatic veins size discrepancy (34 cases). There was no graft loss. The warm ischemia time was 39.65 minutes compared with 37 minutes in the standard PB group. The long-term graft and patient survival rates were similar in the two groups. Infrahepatic vena cavocavostomy is a useful variation of the standard PB technique.

Inferior vena cava encirclement by caudate lobe hypertrophy: evaluation by MRI and CT and its impact on caval preservation during orthotopic liver transplantation

BACKGROUND

Presence of a dorsal sector of liver that completely encircles the IVC may increase difficulty of IVC preservation for orthotopic liver transplantation (OLT). We sought to evaluate the incidence of IVC encirclement by hepatic parenchyma using preoperative MRI and CT and its effect on surgical technique and complications.

METHODS

CT or MRI examinations less than 12 months before OLT were reviewed independently and blindly by two radiologists in 95 patients, with patient consent waived by IRB. IVC preservation was attempted for all patients without regard to imaging findings. Surgical records were reviewed regarding choice of technique or operative difficulties, and their relationship to complete IVC encirclement was calculated using ROC analysis and Fischer exact test.

RESULTS

Complete encirclement was found by both readers in 16 of 95 patients (17%). Resection of the recipient IVC was required in three of 95 patients, two of whom had complete IVC encirclement. Association of complete IVC encirclement with surgical IVC resection had an area under the ROC curve of 0.752.

CONCLUSION

Routine pretransplant assessment of IVC encirclement by dorsal sector hepatic tissue using MRI and CT may help identifying patients in whom IVC preservation will be difficult.

Side-to-side cavocavostomy with an endovascular stapler: Rescue technique for severe hepatic vein and/or inferior vena cava outflow obstruction after liver transplantation using the piggyback technique

Venous outflow obstruction is a rare but potentially lethal complication after orthotopic liver transplantation (OLT) with the "piggyback" technique. Therapeutic options include angioplasty with or without stent placement, surgical reconstruction of the venous anastomosis, and retransplantation. Surgical options are technically very challenging and the outcomes discouraging. We describe here two cases of venous outflow obstruction in recipients of piggyback liver grafts, one involving both the vena cava and hepatic veins and the other affecting only hepatic vein outflow. Both patients were treated successfully with side-to-side cavo-cavostomy using an endovascular (endo-GIA) stapler. This novel technique is fast and effective in resolving the outflow obstruction.

Temporary portocaval shunt in orthotopic liver transplantation: need for a standardized approach?

Maintenance of portal and systemic venous return during the anhepatic phase of liver transplantation (LT) improves hemodynamic stability. With the piggyback technique, caval return is maintained; however, temporary clamping of the portal vein is still necessary. The use of a temporary portocaval shunt (TPCS) has been proposed to minimize the effect of portal venous interruption. The aim of this study was to perform a systematic review of the literature to determine whether there is evidence to support the routine use of a TPCS in LT. An electronic search of the literature from 1963 to 2007 was performed. A total of 4386 articles were identified, of which 8 met all the criteria and were included in the study. Because of the variability in reporting and the small number of studies, statistical comparison was not possible; however, a trend toward a shorter operative time, less blood product transfusion, and maintenance of higher mean arterial pressures during portal vein clamping was seen in patients with a TPCS. In conclusion, the available evidence, albeit scarce, supports the use of a TPCS in patients undergoing LT. A prospective randomized study of patients most likely to benefit from a TPCS is necessary to substantiate these findings.

Midterm and long-term results of percutaneous endovascular treatment of venous outflow obstruction after pediatric liver transplantation

PURPOSE

To evaluate retrospectively the midterm and long-term results of percutaneous endovascular treatment of venous outflow obstruction after pediatric liver transplantation.

MATERIALS AND METHODS

During a 9-year period, 18 children with obstruction of a hepatic vein (HV) or inferior vena cava (IVC) anastomosis underwent percutaneous transluminal angioplasty (PTA) with balloon dilation or stent placement in case of PTA failure after liver transplantation. Patients' body weights ranged from 7.7 kg to 42.6 kg (mean, 18.8 kg +/- 9). Potential predictors of patency were compared between balloon dilation and stent placement groups.

RESULTS

Forty-two procedures were performed (range, 1-11 per patient; mean, 2). Technical and initial clinical success were achieved in all cases. Major complications included one case of pulmonary artery stent embolization and one case of hemothorax. Three children (25%) with HV obstruction were treated with PTA and nine (75%) were treated with stent placement. Three children with IVC obstruction (75%) were treated with PTA and one (25%) was treated with a stent. There were two children with simultaneous obstruction at the HV and IVC; one was treated with PTA and the other with a stent. Cases of isolated HV stenosis have a higher probability of patency with balloon-expandable stent treatment compared with balloon dilation (P < .05). Follow-up time ranged from 7 days to 9 years (mean, 42 months +/- 31), and the primary assisted patency rate was 100% when stent placement was performed among the first three procedures.

CONCLUSIONS

In cases of venous outflow obstruction resulting from HV and/or IVC lesions after pediatric liver transplantation, percutaneous endovascular treatment with balloon dilation or stent placement is a safe and effective alternative treatment that results in long-term patency.

The need for venovenous bypass in liver transplantation

Since introduction of the conventional liver transplantation (CLTx) by Starzl, which was based on the resection of recipient inferior vena cava (IVC) along the liver, the procedure has undergone several refinements. Successful use of venovenous bypass (VVB) was first introduced by Shaw et al., although in recent decades there has been controversy regarding the routine use of VVB during CLTx. With development of piggyback liver transplantation (PLTx), the use of caval clamping and VVB is avoided, leading to fewer complications related to VVB. However, some authors still advocate VVB in PLTx. The great diversity among centers in their use of VVB during CLTx, or even along the PLTx technique, has led to confusion regarding the indication setting for VVB. For this reason, we present an overview of the use of VVB in CLTx, the target of patients for whom VVB could be beneficial, and the needs assessment of VVB for patients undergoing PLTx. Recent studies have shown that with the advancement of surgical skills, refinement of surgical techniques, and improvements in anesthesiology, there are only limited indications for doing CLTx with VVB routinely. PLTx with preservation of IVC can be performed in almost all primary transplants and in the majority of re-transplantations without the need for VVB. Nevertheless, in a few selective cases with severe intra-operative hemodynamic instability, or with a failed test of transient IVC occlusion, the application of VVB is still justifiable. These indications should be judged intra-operatively and the decision is based on each center's preference.

Complications of liver transplantation: multimodality imaging approach

Liver transplantation is currently an accepted first-line treatment for patients with end-stage acute or chronic liver disease, but postoperative complications may limit the long-term success of transplantation. The most common and most clinically significant complications are arterial and venous thrombosis and stenosis, biliary disorders, fluid collections, neoplasms, and graft rejection. Early diagnosis is crucial to the successful management of all these complications, and imaging plays an important role in the diagnosis of all but graft rejection. A multimodality approach including ultrasonography and cross-sectional imaging studies often is most effective for diagnosis. Each imaging modality has specific strengths and weaknesses, and the diagnostic usefulness of a modality depends mainly on the patient's characteristics, the clinical purpose of the imaging evaluation, and the expertise of imaging professionals.

[Significance and specificity of vascular anastomosis in liver transplantation -- our experience]

INTRODUCTION

Transplantation is the method of choice in the treatment of terminal liver diseases with acute and structural damage of liver tissue and congenital liver diseases.

OBJECTIVE

The aim of our study was to determine specificity and significance of vascular anastomosis in liver transplantation by postoperative evaluation of vascular anastomosis function.

METHOD

The study included 16 patients with 16 liver transplantations and one re-do liver transplantation. In all patients, preoperative angiography and postoperative duplex sonographic and angiographic evaluation of vascular anastomosis were performed.

RESULTS

Preoperative angiographic evaluation did not reveal anomalies in liver blood vessels of transplant candidates. In one patient, we identified and angiographically confirmed stenosis on anastomosis of the hepatic artery on the 7th postoperative day. In another patient, we had artificial thrombosis of the hepatic artery branch due to the liver biopsy.

CONCLUSION

The successful performance of vascular anastomosis in liver transplantation is significant for adequate liver graft perfusion, good postoperative graft function and overall outcome of the liver transplantation.

Sonographic evaluation of venous obstruction in liver transplants

OBJECTIVE

The purpose of our study was to identify specific Doppler criteria for portal vein and outflow vein (hepatic veins and inferior vena cava) obstruction in liver transplants.

MATERIALS AND METHODS

A retrospective review was performed of Doppler sonographic studies and angiograms in 94 liver transplant cases (72 whole liver, 22 lobar) with suspected vascular obstruction. The angiograms were classified as normal, occluded, or stenosed on the basis of appearance and elevated pressure gradient. Sonography was correlated with angiography. The following Doppler parameters were evaluated: for the portal vein, peak anastomotic velocity and anastomotic-to-preanastomotic velocity ratio; and for the outflow veins, venous pulsatility index. Receiver operating characteristic curves were constructed and optimum thresholds for stenosis were defined.

RESULTS

There were 16 cases of portal vein obstruction (11 stenosis, five occlusion) and 35 cases of outflow vein obstruction (34 stenoses, one occlusion). Mean peak anastomotic velocity in normal portal veins was 58 cm/s, whereas mean peak anastomotic velocity in stenosed veins was 155 cm/s (p = 0.0007). Peak anastomotic velocity threshold of > 125 cm/s was 73% sensitive and 95% specific for stenosis. Mean anastomotic-to-preanastomotic velocity ratio in normal portal veins was 1.5, and mean anastomotic-to-preanastomotic velocity ratio in stenosed veins was 4.69 (p = 0.001). A 3:1 ratio was 73% sensitive and 100% specific for stenosis. Mean venous pulsatility index for normal outflow veins was 0.75, and mean venous pulsatility index in stenosed veins was 0.39. A venous pulsatility index of < 0.45 was 95.7% specific for stenosis. The areas under the receiver operating characteristic curve were 0.83 for peak anastomotic velocity, 0.86 for anastomotic-to-preanastomotic velocity ratio, and 0.84 for venous pulsatility index, indicating good correlation.

CONCLUSION

Peak anastomotic velocity, anastomotic-to-preanastomotic velocity ratio, and venous pulsatility index are useful parameters for diagnosing venous stenosis in liver transplants.

End-to-side caval anastomosis in adult piggyback liver transplantation

No consensus exists regarding the optimal reconstruction of the cavo-caval anastomosis in piggyback orthotopic liver transplantation (PB-LT). The aim of this study was to analyze our experience with end-to-side (ES) cavo-cavostomy. Outcome parameters were patient and graft survival and surgical complications. During the period 1995-2002 146 full-size PB-LT in 137 adult patients were performed with ES cavo-cavostomy without the routine use of temporary portocaval shunt (TPCS). In 12 patients (8%) this technique was used for implantation of second or third grafts. Veno-venous bypass was not used in any case and TPCS was performed only in eight patients (6%). One-, three- and five-yr patient and graft survival were 84%, 79% and 75%, and 81%, 74% and 69%, respectively. The median number of intraoperative transfusion of packed red blood cells (RBC) was 2.0 (range 0-33) and 30% of the patients (n = 43) did not require any RBC transfusion. Surgical complications of various types were observed after 49 LT (34%) and none of the complications was specifically related to the technique of ES cavo-cavostomy. Our experience indicates that PB-LT with ES cavo-cavostomy is a safe procedure, can safely be performed without the routine use of a TPCS, has a very low risk of venous outflow obstruction and can also be used effectively during retransplantations.