The Impact of Portal Vein Thrombosis on Liver Transplant Outcomes: Does Grade or Flow Rate Matter?

From large-for-size to large-for-flow: A paradigm shift in liver transplantation

Liver graft-recipient matching remains challenging, and both morphologic and hemodynamic characteristics have been shown to be relevant indicators of post-transplant outcomes. However, no combined analysis is available to date. To study the impact of both morphologic and hemodynamic characteristics of liver grafts on transplantation outcomes, we retrospectively evaluated all consecutive 257 liver transplantations with prospective hemodynamic measurements from 2017 to 2020 in a single-center perspective. First, a morphologic analysis compared recipients with or without large-for-size (LFS), defined by a graft/recipient weight ratio >2.5% and excluding extreme LFS. Second, a hemodynamic analysis compared recipients with or without low portal flow (LPF; <80 mL/min per 100 g of liver tissue). Third, an outcome analysis combining LPF and LFS was performed, focusing on liver graft-related morbidity (LGRM), graft and patient survival. LGRM was a composite endpoint, including primary nonfunction, high-risk L-Graft7 category, and portal vein thrombosis. Morphologic analysis showed that LFS (n=33; 12.9%) was not associated with an increased LGRM (12.1% vs 9.4%; p =0.61) or impaired graft and patient survival. However, the hemodynamic analysis showed that LPF (n=43; 16.8%) was associated with a higher LGRM (20.9% vs 7.5%, p = 0.007) and a significantly impaired 90-day graft and patient survival. Multivariable analysis identified LPF but not LFS as an independent risk factor for LGRM (OR: 2.8%; CI:1.088-7.413; and p = 0.03), 90-day (HR: 4%; CI: 1.411-11.551; and p = 0 .01), and 1-year patient survival. LPF is a significant predictor of post-liver transplantation morbi-mortality, independent of LFS when defined as a morphologic metric alone. Consequently, we propose the novel concept of large-for-flow, which may guide graft selection and improve perioperative management of LPF.

Liver Transplantation for Porto-sinusoidal Vascular Liver Disorder: Long-term Outcome

BACKGROUND

Porto-sinusoidal vascular liver disorder (PSVD) is a rare disease that occasionally requires liver transplantation (LT), despite usually presenting preserved liver function. There remains a paucity of data pertaining to LT in PSVD. The aim was to identify features associated with post-LT outcomes in PSVD.

METHODS

Retrospective multicentre study of 79 patients who received LT for PSVD.

RESULTS

Median post-LT follow-up was 37 (range 1-261) mo. Refractory ascites 24 (30%), hepatic encephalopathy 16 (20%), and hepatopulmonary syndrome 13 (16.3%) were the most frequent indications for LT. Hepatocellular carcinoma was the indication in only 2 patients. Twenty-four patients died, 7 due to liver and 17 to non-liver related causes. Post-LT survival was 82.2%, 80.7%, and 68.6% at 1, 2, and 5 y, respectively. Post-LT survival was significantly better in patients without (n = 58) than in those with a persistent severe PSVD-associated condition (n = 21). Pre-LT hyperbilirubinemia levels and creatinine >100 µmol/L were also independently associated with poor survival. Six patients (7.6%) required a second LT. Recurrence of PSVD was confirmed by liver biopsy in only 1 patient and in 3 further patients it was likely.

CONCLUSIONS

LT in PSVD is associated with an acceptable outcome in the absence of associated severe conditions. However, persistence of a severe associated condition, pre-LT high bilirubin levels, or creatinine >100 µmol/L impact outcome, and these are features that should be considered when evaluating PSVD patients for LT. PSVD recurrence is possible after LT and needs to be explored, at least, in cases of posttransplant portal hypertension.

Interventional Approach to Portal Vein Thrombosis and Liver Transplantation: State of the Art

Porto-mesenteric vein thrombosis (PVT) is a well-recognized but uncommon disease entity in patients with and without cirrhosis. Given the complexity of these patients, there are many differing treatment algorithms depending on the individual circumstances of a given patient. The focus of this review is primarily patients with cirrhosis, with an emphasis on liver transplantation considerations. The presence of cirrhosis substantially affects work-up, prognosis, and management of these patients and will substantially affect the patient treatment and have additional implications for prognosis and long-term outcomes. Here, we review the incidence of portal vein thrombosis in known cirrhotic patients, medical and interventional treatment options that are currently used, and, in particular, how to approach cirrhotic patients with PVT who are awaiting liver transplantation.

Recurrent Portal Vein Thrombosis In Liver Transplantation With Renoportal Anastomosis Caused by Spontaneous Reno-Caval Shunts: A Case Report

BACKGROUND

Orthotopic liver transplantation (OLT) in patients with cirrhosis complicated by portal hypertension, portosystemic shunts, and chronic portal vein thrombosis (PVT) has long been challenging. Spontaneous spleno-renal shunts (SRS) allow new surgical techniques to restore portal vein patency and hepatopetal flow. Renoportal anastomosis (RPA) has emerged as an accepted method for transplanting these patients, with good long-term patient and graft survival. Orthotopic liver transplantation with RPA is known to be complicated by recurrent PVT, with few details discussed in the literature.

CASE REPORT

We present a case of a 56-year-old woman with decompensated cirrhosis who underwent deceased donor whole graft OLT using RPA with iliac vein conduit. The postoperative course was complicated by occlusive thrombosis in the portal vein and iliac vein conduit. Venography revealed enlarged left gonadal and lumbar vein varices acting as reno-caval shunts with hepatofugal flow. Embolization of the varices re-established durable venous patency that was confirmed on post-transplant day 68 with no other hemodynamic complications.

DISCUSSION

This showcases an interesting mechanism by which recurrent PVT may occur in patients undergoing OLT with RPA. Because durable portal vein patency can be achieved with Interventional Radiology embolization of reno-caval varices, assessing these communications is an important preoperative consideration for planned OLT with RPA.

Are short-term complications associated with poor allograft and patient survival after liver transplantation? A systematic review of the literature and expert panel recommendations

BACKGROUND

Maximizing patient and allograft survival after liver transplant (LT) is important from both a patient care and organ utilization perspective. Although individual studies have addressed the effects of short-term post-LT complications on a limited scale, there has not been a systematic review of the literature formally assessing the potential effects of early complications on long-term outcomes.

OBJECTIVES

To identify whether short-term complications after LT affect allograft and overall survival, to identify short-term complications of particular clinical interest and significance, and to provide recommendations to improve post-LT graft and patient survival.

DATA SOURCES

Ovid MEDLINE, Embase, Scopus, Google Scholar, and Cochrane Central.

METHODS

A systematic review following PRISMA guidelines and recommendations using the GRADE approach derived from an international expert panel.

RESULTS

The literature review and analysis provided show that short-term complications have a large impact on allograft and patient survival after LT. The complications with the strongest effect on survival are acute kidney injury (AKI), biliary complications, and early allograft dysfunction (EAD).

CONCLUSION

This panel recommends taking measures to reduce the risk and incidence of short-term complications post-LT. Clinicians should pay particular attention to preventing or ameliorating AKI, biliary complications, and EAD (Quality of evidence; Moderate | Grade of Recommendation; Strong).

What is the optimal management of thromboprophylaxis after liver transplantation regarding prevention of bleeding, hepatic artery, or portal vein thrombosis? A systematic review of the literature and expert panel recommendations

BACKGROUND

A key tenet of clinical management of patients post liver transplantation (LT) is the prevention of thrombotic and bleeding complications. This systematic review investigated the optimal management of thromboprophylaxis after LT regarding portal vein thrombosis (PVT) or hepatic artery thrombosis (HAT) and prevention of bleeding.

METHODS

Systematic review following PRISMA guidelines and recommendations using the GRADE approach derived from an international expert panel. Seven databases were used to conduct extensive literature searches focusing on the use of anticoagulation in LT and its impact on the following outcomes: PVT, HAT, and bleeding (CRD42021244288).

RESULTS

Of the 2478 articles/abstracts screened, 16 studies were included in the final review. All articles were critically appraised by a panel of independent reviewers. There was wide variation regarding the anticoagulation protocols used. Thromboprophylaxis with therapeutic doses of heparin/Vitamin K antagonist combination did not decrease the risk of de novo or the recurrence of PVT but was associated with an increased risk of bleeding in some studies. Only the use of aspirin resulted in a small but significant decrease in the incidence of HAT post-LT, yet it did not increase the risk of bleeding.

CONCLUSIONS

Based on existing data and expert opinion, thromboprophylaxis at therapeutic or prophylactic dose is not recommended for prevention of de novo PVT following LT in patients not at high risk. Aspirin should be considered as the standard of care following LT to prevent HAT. Thromboprophylaxis should be strongly considered in recipients at risk of HAT and PVT following LT.

The Management of Portal Vein Thrombosis after Adult Liver Transplantation: A Case Series and Review of the Literature

Background: Portal vein thrombosis (PVT) after adult liver transplantation (LT) is a rare but serious complication with no consensus on the ideal treatment. We report a case series and a comprehensive review of the literature on PVT after LT to discuss the therapeutic options. Methods: The clinical data of 360 adult patients (≥18 years of age) who underwent LT from January 2017 to January 2020 were reviewed, and a comprehensive search of PubMed and Web of Science was conducted. Patients diagnosed with PVT after LT were identified, and relevant risk factors and therapies were analyzed. Results: Among the 360 patients, 7 (1.94%) developed PVT after LT. Onset of PVT within one week after LT was found in six patients (85.71%). Four of the seven patients with PVT received systemic anticoagulation (low molecular weight heparin and warfarin) therapy. Minimally invasive interventional therapies combined with systemic anticoagulation (heparin and warfarin) were applied for three patients, two of whom died because of severe abdominal hemorrhage and liver failure. Of the 33 cases reported in the literature, minimally invasive interventional therapy combined with systematic anticoagulation or sclerotherapy were the most-used methods (20/33). Systemic anticoagulation was administered to four patients, and surgical operation (thrombectomy; portosystemic shunt and retransplantation) was performed for nine patients. Among these 33 patients, 4 eventually died. Conclusions: Interventional therapy combined with systemic anticoagulation is a good choice for the management of PVT after LT, and in our experience, systemic anticoagulation alone can also have a positive effect for early PVT patients.

Therapeutic anticoagulation after liver transplantation is not useful among patients with pre-transplant Yerdel-grade I/II portal vein thrombosis: A two-center retrospective study

BACKGROUND

Portal vein thrombosis (PVT) is no longer a contraindication for liver transplantation (LT). While therapeutic anticoagulation (tAC) is recommended during the waiting period, there is no evidence for its usefulness in the prevention of PVT recurrence after LT.

OBJECTIVES

The aim of our study was to evaluate the role of tAC post-LT in the prevention of PVT recurrence.

PATIENTS/METHODS

All adult LTs performed in two high-volume centers between 2003 and 2018 were retrospectively analysed. Only patients with PVT classified as Yerdel grade I or II and with standard portal reconstruction were included. PVT recurrence and tAC-associated morbidity within 1 year were compared between patients receiving tAC or not.

RESULTS

During the study period, of 2612 LTs performed, 235 (9%) patients with PVT were included; 113 patients (48.1%) received post-LT tAC (tAC group) while 122 (51.9%) did not (non-tAC group). The incidence of bleeding events was significantly higher in the tAC group (26 [23%] vs. 5 [4.1%], P < .01) and the initial hospitalization duration was longer (21 vs. 17.5 days, P < .01). Within the first year, PVT recurrence was observed for 9 (3.8%) patients without any difference between the tAC and non-tAC groups (6 [5.1%] vs. 3 [2.5%], P = .39). The only identified risk factor for PVT recurrence was the recipients' age (odds ratio= 0.94, P = .03). Graft (P = .11) and patient (P = .44) survival were similar between the two groups.

CONCLUSION

Therapeutic anticoagulation is not necessary in the prevention of grade I/II PVT recurrence and is associated with higher morbidity and longer hospital stay.

Restoration of portal flow with varix in liver transplantation for patients with total portal vein thrombosis: An effective strategy in the largest center experience

INTRODUCTION

Postoperative complications and worse prognosis still burden liver transplantations (LT) with complex portal vein thrombosis (CPVT). When an engorged left gastric vein (LGV) is present, the portal inflow is restorable with an anastomosis between the graft portal vein and the LGV of the recipient. We analyzed short- and long-term results of this procedure in 12 LT with CPVT.

METHODS

Between 2005 and 2019, 55 patients with CPVT underwent LT. We applied this technique in 12 patients. In six cases, we placed a vascular graft to obtain a tension-free structure. We evaluated patency, short- and long-term results.

RESULTS

No intraoperative complication was observed. The median duration of LT, blood transfusion, deceased donor age, and MELD score of the recipients were 7 h, 1250 mL, 72 years, and 19. Seven patients were affected by hepatocellular carcinoma. No major complications or PVT recurrence were observed. One patient required a liver re-transplantation for primary non-functioning syndrome. The mean hospital stay was 20 days. The actuarial patient survival was 85% with a mean FU of 4 years. The two late deaths were due to hepatocellular carcinoma recurrence and sepsis for cholangitis.

CONCLUSIONS

This technique in presence of both CPVT and engorged LGV is feasible and safe for patients, with good short- and long-term results.