Safety and effectiveness of renoportal bypass in patients with complete portal vein thrombosis: an analysis of 10 patients

Alternative forms of portal vein revascularization in liver transplant recipients with complex portal vein thrombosis

BACKGROUND & AIMS

Complex portal vein thrombosis (PVT) is a challenge in liver transplantation (LT). Extra-anatomical approaches to portal revascularization, including renoportal (RPA), left gastric vein (LGA), pericholedochal vein (PCA), and cavoportal (CPA) anastomoses, have been described in case reports and series. The RP4LT Collaborative was created to record cases of alternative portal revascularization performed for complex PVT.

METHODS

An international, observational web registry was launched in 2020. Cases of complex PVT undergoing first LT performed with RPA, LGA, PCA, or CPA were recorded and updated through 12/2021.

RESULTS

A total of 140 cases were available for analysis: 74 RPA, 18 LGA, 20 PCA, and 28 CPA. Transplants were primarily performed with whole livers (98%) in recipients with median (IQR) age 58 (49-63) years, model for end-stage liver disease score 17 (14-24), and cold ischemia 431 (360-505) minutes. Post-operatively, 49% of recipients developed acute kidney injury, 16% diuretic-responsive ascites, 9% refractory ascites (29% with CPA, p <0.001), and 10% variceal hemorrhage (25% with CPA, p = 0.002). After a median follow-up of 22 (4-67) months, patient and graft 1-/3-/5-year survival rates were 71/67/61% and 69/63/57%, respectively. On multivariate Cox proportional hazards analysis, the only factor significantly and independently associated with all-cause graft loss was non-physiological portal vein reconstruction in which all graft portal inflow arose from recipient systemic circulation (hazard ratio 6.639, 95% CI 2.159-20.422, p = 0.001).

CONCLUSIONS

Alternative forms of portal vein anastomosis achieving physiological portal inflow (i.e., at least some recipient splanchnic blood flow reaching transplant graft) offer acceptable post-transplant results in LT candidates with complex PVT. On the contrary, non-physiological portal vein anastomoses fail to resolve portal hypertension and should not be performed.

IMPACT AND IMPLICATIONS

Complex portal vein thrombosis (PVT) is a challenge in liver transplantation. Results of this international, multicenter analysis may be used to guide clinical decisions in transplant candidates with complex PVT. Extra-anatomical portal vein anastomoses that allow for at least some recipient splanchnic blood flow to the transplant allograft offer acceptable results. On the other hand, anastomoses that deliver only systemic blood flow to the allograft fail to resolve portal hypertension and should not be performed.

Reconstructing the portal vein through a posterior pancreatic tunnel: New choice for portal vein thrombosis during liver transplantation

BACKGROUND

Thrombectomy and anatomical anastomosis (TAA) has long been considered the optimal approach to portal vein thrombosis (PVT) in liver transplantation (LT). However, TAA and the current approach for non-physiological portal reconstructions are associated with a higher rate of complications and mortality in some cases.

AIM

To describe a new choice for reconstructing the portal vein through a posterior pancreatic tunnel (RPVPPT) to address cases of unresectable PVT.

METHODS

Between August 2019 and August 2021, 245 adult LTs were performed. Forty-five (18.4%) patients were confirmed to have PVT before surgery, among which seven underwent PV reconstruction via the RPVPPT approach. We retrospectively analyzed the surgical procedure and postoperative complications of these seven recipients that underwent PV reconstruction due to PVT.

RESULTS

During the procedure, PVT was found in all the seven cases with significant adhesion to the vascular wall and could not be dissected. The portal vein proximal to the superior mesenteric vein was damaged in one case when attempting thrombolectomy, resulting in massive bleeding. LT was successfully performed in all patients with a mean duration of 585 min (range 491-756 min) and mean intraoperative blood loss of 800 mL (range 500-3000 mL). Postoperative complications consisted of chylous leakage (n = 3), insufficient portal venous flow to the graft (n = 1), intra-abdominal hemorrhage (n = 1), pulmonary infection (n = 1), and perioperative death (n = 1). The remaining six patients survived at 12-17 mo follow-up.

CONCLUSION

The RPVPPT technique might be a safe and effective surgical procedure during LT for complex PVT. However, follow-up studies with large samples are still warranted due to the relatively small number of cases.

Physiological reno-portal bypass in liver transplantation with non-tumorous portal vein thrombosis

Reno-portal anastomosis (RPA) in presence of spleno-renal shunts (SRS) is a physiological option to restore blood flow in liver transplantation with portal vein thrombosis (PVT). Diffuse splanchnic venous system thrombosis (complex PVT) is its main indication but RPA proved to be useful in selected cases of less extensive thrombosis (non-complex PVT). Up until now only two monocentric and one multicentric case series has been published on this topic in addition to few anecdotal reports. After 2014, we introduced RPA in our institution to manage some cases of complex PVT in presence of SRS. Here, we present the evolution of indication to RPA. From 2014 to 2020, we performed ten RPA: nine patients presented non-complex and one complex PVT. Overall early and late complication rates were 66.6% and 50%, respectively. Two patients developed RPA stenosis, treated by interventional radiology. Self-resolving acute kidney injury (AKI) was observed in three cases. No re-transplantation was necessary. RPA was patent in all patients, with a mean follow-up of 41.9 months. The overall patient survival was 70% at 1 year and 60% at 3 and 5 years. Four patients died at 1, 2, 3 and 20 months from LT. Causes of deaths were, respectively, stroke, cerebral infection, sepsis (MOF) and sudden variceal bleeding in sinusoidal obstruction syndrome. The relative simplicity and effectiveness of RPA in presence of SRS allowed us to rely more and more often on this technique in liver transplantation with challenging non-complex PVT.

Optimal Treatment for Patients With Cavernous Transformation of the Portal Vein

Cavernous transformation of the portal vein (CTPV) is a sequela of extrahepatic and/or intrahepatic portal vein obstruction caused by a combination of local and risk factors. It was ever taken as a relatively rare disease due to its scant literature, which was mainly based on clinical series and case reports. CTPV often manifests as gastroesophageal variceal bleeding, splenomegaly, and portal biliopathy after the long-term insidious presentation. It is unable for CTPV to be recanalized with anticoagulation because it is a complete obstruction of the mesentericoportal axis. Endoscopic therapy is mainly used for temporary hemostasis in acute variceal bleeding. Meso-Rex shunting characterized by portal-flow-preserving shunts has been widely performed in children with CTPV. The multitude of complications associated with CTPV in adults can be effectively addressed by various interventional vascular therapies. With the ubiquity of radiological examinations, optimal treatment for patients with CTPV becomes important. Multivisceral transplantation, such as liver-small intestinal transplantation, may be lifesaving and should be considered for patients with diffuse mesenteric venous thrombosis.

Liver transplantation in patients with non-neoplastic portal vein thrombosis: 20 years of experience in a single center

BACKGROUND

The Yerdel classification is widely used for describing the severity of portal vein thrombosis (PVT) in liver transplant (LT) candidates, but might not accurately predict transplant outcome.

METHODS

We retrospectively analyzed data regarding 97 adult patients with PVT who underwent LT, investigating whether the complexity of portal reconstruction could better correlate with transplant outcome than the site and extent of the thrombosis.

RESULTS

79/97 (80%) patients underwent thrombectomy and anatomical anastomosis (TAA), 18/97 (20%) patients underwent non-anatomical physiological reconstructions (non-TAA). PVT Yerdel grade was 1-2 in 72/97 (74%) patients, and 3-4 in 25/97 (26%) patients. Univariate analysis revealed higher 30-day mortality, 90-day mortality, 1-year mortality, and a higher rate of severe early complications in the non-TAA group than in the TAA group (p = .018, .001, .014, .009, respectively). In the model adjusted for PVT Yerdel grade, non-TAA remained independently associated with higher 30-day, 90-day, and 1-year mortality (p = .021, .007, and .015, respectively). The portal vein re-thrombosis and overall patient and graft survival rates were similar.

DISCUSSION

In our experience, the complexity of portal reconstruction better correlated with transplant outcome than the Yerdel classification, which did not even appear to be a reliable predictor of the surgical complexity and technique.

Collaterals in portal hypertension: anatomy and clinical relevance

Portal hypertension is a key pathophysiology of chronic liver diseases typified with cirrhosis or noncirrhotic portal hypertension. The development of collateral vessels is a characteristic feature of impaired portal hemodynamics. The paraumbilical vein (PUV), left gastric vein (LGV), posterior gastric vein (PGV), short gastric vein (SGV), splenorenal shunt (SRS), and inferior mesenteric vein (IMV) are major collaterals, and there are some rare collaterals. The degree and hemodynamics of collateral may affect the portal venous circulation and may compensate for the balance between inflow and outflow volume of the liver. Additionally, the development of collateral shows a relation with the liver function reserve and clinical manifestations such as esophageal varices (EV), gastric varices, rectal varices and the other ectopic varices, hepatic encephalopathy, and prognosis. Furthermore, there may be an interrelationship in the development between different collaterals, showing additional influences on the clinical presentations. Thus, the assessment of collaterals may enhance the understanding of the underlying pathophysiology of the condition of patients with portal hypertension. This review article concluded that each collateral has a specific function depending on the anatomy and hemodynamics and is linked with the relative clinical presentation in patients with portal hypertension. Imaging modalities may be essential for the detection, grading and evaluation of the role of collaterals and may help to understand the pathophysiology of the patient condition. Further investigation in a large-scale study would elucidate the basic and clinical significance of collaterals in patients with portal hypertension and may provide information on how to manage them to improve the prognosis as well as quality of life.

Liver transplantation in the setting of a spontaneous shunt between superior mesenteric vein and right renal vein

Shunts between the superior mesenteric vein (SMV) and the right renal vein (RRV) are very rare. Here, we describe and depict the rare case of a liver transplant (LT) in the setting of shunt between SMV and RRV. A 67-year-old white man presenting with Child C cirrhosis secondary to hemochromatosis and persistent encephalopathy was listed for LT. Preoperative abdominal angiotomography revealed the presence of a large spontaneous shunt between the SMV and the RRV. The patient underwent LT by receiving a liver from a 17-year-old brain-dead deceased donor victim of trauma. A large shunt between the SMV and the RRV was confirmed intraoperatively. Although there was no portal vein (PV) thrombosis, the PV was atrophic and had a reduced flow. PV pressure was 22mmHg (an arterial line was inserted inside the PV stump, and this line was connected to a common pressure transducer, the pressure readings was expressed in the anesthesia monitor). After shunt ligation PV pressure increased to 32mmHg. There were no post-transplant vascular complications, and the patient was discharged home in good health. Preoperative study of all LT candidates with angio CT scan is mandatory. Whenever there is PV thrombosis, an attempt to remove the entire thrombus is warranted. After thrombectomy or whenever there is not PV thrombosis, all large shunts should be ligated. PV pressure and flow should be measured before and after shunt ligation. In the absence of PV thrombosis, ligation of the shunt should enable an increase in PV flow and pressure, as reported herein.

Long term outcomes and complications of reno-portal anastomosis in liver transplantation: results from a propensity score-based outcome analysis

Diffuse splanchnic vein thrombosis (DSVT) remains a serious challenge in liver transplantation (LT). Reno-portal anastomosis (RPA) has previously been reported as a valid option for management of patients with DSVT during LT. The aim of this study was to evaluate post-transplant renal function and surgical outcomes of patients with DSVT who underwent RPA during LT. Between January 2005 and December 2017, 1270 patients underwent LT at our institution, including 16 with DSVT managed with RPA (RPA group). We compared renal function and surgical outcomes in these patients to outcomes in 48 propensity score (PS)-matched patients without thrombosis (control group), using a 1:3 matching model. The two groups had similar rates of postoperative portal vein thrombosis (PVT), renal dysfunction as measured by estimated glomerular filtration rate (eGFR), and overall postoperative complications (Clavien grade III), although the RPA group had a higher incidence of postoperative upper gastrointestinal (GI) bleeding (31.3% vs 4.2%; P = 0.009) that had no clinical consequence. There were no significant differences in five-year graft and patient survival rates between the groups (P = 0.133 and P = 0.166, respectively). RPA is an established technique in the management of patients with DSVT during LT, with comparable outcomes to patients without thrombosis. Our report is the first to demonstrate similar surgical outcomes, including long-term renal function, in LT recipients with or without RPA.

Liver Transplantation

The field of liver transplantation has changed since the MELD scoring system became the most widely used donor allocation tool. Due to the MELD-based allocation system, sicker patients with higher MELD scores are being transplanted. Persistent organ donor shortages remain a challenging issue, and as a result, the wait-list mortality is a persistent problem for most of the regions. This chapter focuses on deceased donor and live donor liver transplantation in patients with complications of portal hypertension. Special attention will also be placed on donor-recipient matching, perioperative management of transplant patients, and the impact of hepatic hemodynamics on transplantation.

Novel classification of non-malignant portal vein thrombosis: A guide to surgical decision-making during liver transplantation

Non-tumoral portal vein thrombosis (PVT) is present at liver transplantation in 5% to 26% of cirrhotic patients, and the prevalence of complex PVT as defined here (grade 4 Yerdel, and grade 3,4 Jamieson and Charco) has been reported in 0% to 2.2%. Adequate portal inflow is mandatory to ensure graft and patient survival after liver transplantation. With time, the proposed classifications of non-tumoral chronic PVT have evolved from being anatomy-based, to also incorporating functional parameters. However, none of the currently proposed classifications are directed towards decision-making, regarding the choice of inflow to the graft during transplantation and the outcomes thereof. The present scoping review i) addresses the limits of the currently available classifications in terms of surgical decisiveness, ii) clarifies the concept of physiological or non-physiological portal inflow reconstruction, and subsequently, iii) proposes a new classification of non-tumoral PVT in candidates for liver transplantation; to help tailor the surgical strategy to an individual patient, in order to provide portal inflow to the graft together with control of prehepatic portal hypertension whenever feasible.

Reno-portal shunt for liver transplant, an alternative inflow for recipients with grade III-IV portal vein thrombosis: Tips for a better outcome

INTRODUCTION

Portal vein thrombosis (PVT) poses an extremely difficult problem in cirrhotic patients who are in need of a liver transplant. The prevalence of PVT in patients with cirrhosis ranges from 0.6% to 26% Nery et al. (2015) [1]. The presence of PVT is associated with more technically difficult liver transplant and in certain cases can be a contraindication to liver transplant. The only option for these patients with extensive PVT would be a multi-visceral transplant, the later unfortunately has a much higher morbidity and mortality compared to liver only transplant Smith et al. (2016) [2]. An alternative approach is needed to provide a safe and reliable outcome.

PRESENTATION OF CASE

In this case series, we present our experience with reno-portal shunt as an alternative inflow for the liver allograft.

DISCUSSION

This approach appears to be safe with good long-term outcome.Although this technique has been described before, we provide additional considerations that produced good outcomes in our patients.

CONCLUSION

We believe that meticulous preoperative planning with high-resolution triple phase CT imaging with a measurement of the diameter of the spleno-renal shunt along with a duplex scan measuring flow through the shunt is key to a successful transplantation. Moreover, appropriate donor liver size is also of extreme importance to avoid portal hypoperfusion.

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

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

Significance of measured intraoperative portal vein flows after thrombendvenectomy in deceased donor liver transplantations with portal vein thrombosis

Adequate portal vein (PV) flow in liver transplantation is essential for a good outcome, and it may be compromised in patients with portal vein thrombosis (PVT). This study evaluated the impact of intraoperatively measured PV flow after PV thrombendvenectomy on outcomes after deceased donor liver transplantation (DDLT). The study included 77 patients over a 16-year period who underwent PV thrombendvenectomy with complete flow data. Patients were classified into 2 groups: high PV flow (>1300 mL/minute; n = 55) and low PV flow (≤1300 mL/minute; n = 22). Postoperative complications and graft survival were analyzed according to the PV flow. The 2 groups were similar in demographic characteristics. Low PV flow was associated with higher cumulative rates of biliary strictures (P = 0.02) and lower 1-, 2-, and 5-year graft survival (89%, 85%, and 68% versus 64%, 55%, and 38%, respectively; P = 0.002). There was no difference in the incidence of postoperative PVT between the groups (1.8% versus 9.1%; P = 0.19). No biliary leaks or hepatic artery thromboses were reported in either group. By multivariate analyses, age >60 years (hazard ratio [HR], 3.04, 95% confidence interval [CI], 1.36-6.82; P = 0.007) and low portal flow (HR, 2.31; 95% CI, 1.15-4.65; P = 0.02) were associated with worse survival. In conclusion, PV flow <1300 mL/minute after PV thrombendvenectomy for PVT during DDLT was associated with higher rates of biliary strictures and worse graft survival. Consideration should be given to identifying reasons for low flow and performing maneuvers to increase PV flow when intraoperative PV flows are <1300 mL/minute. Liver Transplantation 23 1032-1039 2017 AASLD.

Balloon-Occlusion Technique for Managing Portal Vein Hemorrhage in Liver Transplantation

BACKGROUND

Portal vein thrombosis (PVT) is relatively common among candidates for liver transplantation and can present significant intraoperative challenges. Depending on the extent of PVT, thromboendovenectomy (TEV), portal bypass, or systemic inflow may be required to restore portal inflow. While TEV is the most commonly used approach to restore anatomic portal inflow, portal vein injury and life-threatening hemorrhage are risks with this technique.

CASE REPORT

We present a salvage technique for managing portal vein injury during TEV using intraluminal balloon occlusion of the portal vein during portal vein repair and reconstruction. This alternative mode of bleeding control optimizes exposure to the retropancreatic space and avoids direct application of vascular clamps that can cause further injury to the vessel and surrounding tissue.

CONCLUSION

Careful preoperative planning and anticipation of potential problems are essential for safe and effective management of complex PVT intraoperatively. The balloon-occlusion technique can facilitate safe and efficient repair of a portal vein injury during TEV for liver transplantation.

Liver transplant recipients with portal vein thrombosis receiving an organ from a high-risk donor are at an increased risk for graft loss due to hepatic artery thrombosis

We hypothesize that recipients with pretransplant portal vein thrombosis (PVT) receiving organs from high-risk donors (HRD) are at an increased risk of HAT. Data on all liver transplants in the United States from February 2002 to March 2015 were analyzed. Recipients were sorted into two groups: those with PVT and those without. HRDs were defined by donor risk index (DRI) >1.7. Multivariable logistic regression models were constructed to assess the independent risk factors for HAT with the resultant graft loss ≤90 days from transplantation. A total of 60 404 candidates underwent liver transplantation; of those recipients, 623 (1.0%) had HAT, of which 66.0% (n = 411) received organs from HRDs compared with 49.3% (n = 29 473) in recipients without HAT (P < 0.001); 2250 (3.7%) recipients had pretransplantation PVT and received organs from HRDs. On adjusted multivariable analysis, PVT with a HRD organ was the most significant independent risk factor (OR 3.56, 95% CI 2.52-5.02, P < 0.001) for the development of HAT. Candidates with pretransplant PVT who receive an organ from a HRD are at the highest risk for postoperative HAT independent of other measurable factors. Recipients with pretransplant PVT would benefit from careful donor selection and possibly anticoagulation perioperatively.

Nontumoral portal vein thrombosis in patients awaiting liver transplantation

Portal vein thrombosis (PVT) occurs in approximately 2%-26% of the patients awaiting liver transplantation (LT) and is no longer an absolute contraindication for LT. Nearly half of PVT cases are accidentally found during the LT procedure. The most important risk factor for PVT development in cirrhosis may be the severity of liver disease and reduced portal blood flow. Whether other inherited or acquired coagulation disorders also play a role is not yet clear. The development of PVT may have no effect on the liver disease progression, especially when it is nonocclusive. PVT may not increase the risk of wait-list mortality, but it is a risk factor for poor early post-LT mortality. Anticoagulation and transjugular intrahepatic portosystemic shunt (TIPS) are 2 major treatment strategies for patients with PVT on the waiting list. The complete recanalization rate after anticoagulation is approximately 40%. The role of TIPS to maintain PV patency for LT as the primary indication has been reported, but the safety and efficacy should be further evaluated. PVT extension and degree may determine the surgical technique to be used during LT. If a "conventional" end-to-end portal anastomotic technique is used, there is not a major impact on post-LT survival. Post-LT PVT can significantly reduce both graft and patient survival after LT and can preclude future options for re-LT.

Impact of different immunosuppressive regimens on the health-related quality of life following orthotopic liver transplantation

BACKGROUND

The influence of immunosuppression on the recipients' quality of life (QoL) is of major importance after OLT and has not yet been evaluated.

METHODS

The impact of different immunosuppression regimens after OLT was evaluated in 275 patients using the Short Form 36 (SF-36) survey. The following immunosuppressive strategies were compared: (a) CNI, (b) mTOR inhibitors, and (c) mTOR combined with CNI. All regimens were prescribed alone (mono) or in combination (+) with prednisolone and/or mycophenolate mofetil (MMF).

RESULTS

Highest scores were evident in patients in the mTOR+ group. There were significantly higher values for general health perceptions (GH, p = 0.049), vitality (VIT, p = 0.020), and physical component summary (PCS, p = 0.041) when compared to CNImono and for GH (p = 0.042) and VIT (p = 0.043), when compared to mTORmono. Early conversion to mTOR inhibitors (<two months after OLT) was associated with higher values for 7 of 10 scales, when compared to a late conversion (>two months after OLT), with a statistically significant improvement for the dimension role-emotional (RE, p = 0.027).

DISCUSSION

mTOR inhibitor-based regimens appear to have beneficial effects on QoL after OLT, especially after an early conversion.