Harmful and Beneficial Effects of Anticoagulants in Patients With Cirrhosis and Portal Vein Thrombosis

Nontumoral Portal Vein Thrombosis: A Challenging Consequence of Liver Cirrhosis

Nontumoral portal vein thrombosis (PVT) is an increasingly recognized complication in patients with cirrhosis. Substantial evidence shows that portal flow stasis, complex thrombophilic disorders, and exogenous factors leading to endothelial dysfunction have emerged as key factors in the pathogenesis of PVT. The contribution of PVT to hepatic decompensation and mortality in cirrhosis is debatable; however, the presence of an advanced PVT increases operative complexity and decreases survival after transplantation. The therapeutic decision for PVT is often determined by the duration and extent of thrombosis, the presence of symptoms, and liver transplant eligibility. Evidence from several cohorts has demonstrated that anticoagulation treatment with vitamin K antagonist or low molecular weight heparin can achieve recanalization of the portal vein, which is associated with a reduction in portal hypertension-related events and improved survival in cirrhotic patients with PVT. Consequently, interest in direct oral anticoagulants for PVT is increasing, but clinical data in cirrhosis are limited. Although the most feared consequence of anticoagulation is bleeding, most studies indicate that anticoagulation therapy for PVT in cirrhosis appears relatively safe. Interestingly, the data showed that transjugular intrahepatic portosystemic shunt represents an effective adjunctive therapy for PVT in cirrhotic patients with symptomatic portal hypertension if anticoagulation is ineffective. Insufficient evidence regarding the optimal timing, modality, and duration of therapy makes nontumoral PVT a challenging consequence of cirrhosis. In this review, we summarize the current literature and provide a potential algorithm for the management of PVT in patients with cirrhosis.

Low-molecular-weight heparin followed by rivaroxaban for acute occlusive portomesenteric vein thrombosis in a cirrhotic patient treated with multiple endoscopic variceal procedures

Acute portomesenteric vein thrombosis is potentially lethal. In the present paper, a cirrhotic patient with a previous history of esophageal variceal bleeding presented with acute occlusive portomesenteric vein thrombosis, but achieved complete recanalization by low-molecular-weight heparin followed by rivaroxaban. Notably, no bleeding episode occurred during anticoagulation therapy. This case supported early initiation of anticoagulation in such patients.

New Insights into the Pathogenesis, Risk Factors, and Treatment of Portal Vein Thrombosis in Patients with Cirrhosis

Portal vein thrombosis (PVT) is a frequent event in patients with cirrhosis regardless of etiology. Notwithstanding the commonality of the problem, the pathophysiology and risk factors for PVT in cirrhosis are largely unknown. The clinical impact of PVT in the natural history of cirrhosis is unclear, indications for PVT treatment are not well defined, and treatment recommendations are based on experts' opinion and consensus only. Therefore, this review aims to summarize current knowledge of mechanisms and risk factors for PVT development and assess the current evidence of PVT management, with a special focus on strategies of anticoagulation and transjugular intrahepatic portosystemic shunt placement.

Total area of spontaneous portosystemic shunts independently predicts hepatic encephalopathy and mortality in liver cirrhosis

BACKGROUND & AIMS

Spontaneous portosystemic shunts (SPSS) frequently develop in liver cirrhosis. Recent data suggested that the presence of a single large SPSS is associated with complications, especially overt hepatic encephalopathy (oHE). However, the presence of >1 SPSS is common. This study evaluates the impact of total cross-sectional SPSS area (TSA) on outcomes in patients with liver cirrhosis.

METHODS

In this retrospective international multicentric study, CT scans of 908 cirrhotic patients with SPSS were evaluated for TSA. Clinical and laboratory data were recorded. Each detected SPSS radius was measured and TSA calculated. One-year survival was the primary endpoint and acute decompensation (oHE, variceal bleeding, ascites) was the secondary endpoint.

RESULTS

A total of 301 patients (169 male) were included in the training cohort. Thirty percent of all patients presented with >1 SPSS. A TSA cut-off of 83 mm² was used to classify patients with small or large TSA (S-/L-TSA). Patients with L-TSA presented with higher model for end-stage liver disease score (11 vs. 14) and more commonly had a history of oHE (12% vs. 21%, p <0.05). During follow-up, patients with L-TSA experienced more oHE episodes (33% vs. 47%, p <0.05) and had lower 1-year survival than those with S-TSA (84% vs. 69%, p <0.001). Multivariate analysis identified L-TSA (hazard ratio 1.66; 95% CI 1.02-2.70, p <0.05) as an independent predictor of mortality. An independent multicentric validation cohort of 607 patients confirmed that patients with L-TSA had lower 1-year survival (77% vs. 64%, p <0.001) and more oHE development (35% vs. 49%, p <0.001) than those with S-TSA.

CONCLUSION

This study suggests that TSA >83 mm² increases the risk for oHE and mortality in patients with cirrhosis. Our results support the clinical use of TSA/SPSS for risk stratification and decision-making in the management of patients with cirrhosis.

LAY SUMMARY

The prevalence of spontaneous portosystemic shunts (SPSS) is higher in patients with more advanced chronic liver disease. The presence of more than 1 SPSS is common in advanced chronic liver disease and is associated with the development of hepatic encephalopathy. This study shows that total cross-sectional SPSS area (rather than diameter of the single largest SPSS) predicts survival in patients with advanced chronic liver disease. Our results support the clinical use of total cross-sectional SPSS area for risk stratification and decision-making in the management of SPSS.

Treatment response and bleeding events associated with anticoagulant therapy of portal vein thrombosis in cirrhotic patients: Systematic review and meta-analysis

Background

Well-defined guidelines for the treatment of portal vein thrombosis (PVT) in patients with cirrhosis are lacking, given the paucity of robust data. Among the available treatment options the best choice is unknown.

Methods

We conducted a comprehensive search of multiple electronic databases and conference proceedings (through December 2019) to identify studies that reported on the use of anticoagulants in the treatment of PVT in patients with cirrhosis. Our goals were to evaluate the pooled odds ratio (OR) and pooled rate of treatment responders and bleeding events.

Results

A total of 17 studies were included: 648 patients were treated with anticoagulation and 96 were controls. Pooled OR for treatment responders was 5.1 (95% confidence interval [CI] 2.5-10.2, P = 0.001) and pooled OR for bleeding was 0.4 (95%CI 0.1-1.5, P = 0.2) for anticoagulation treatment versus control. Pooled rate of treatment responders with anticoagulation was 66.7% (95%CI 58.3-74.1) compared to 26% (95%CI 14.2-42.7) for the control group. Pooled rate of bleeding seemed comparable (7.8%, 95%CI 4.5-13.3, and 15.4%, 95%CI 4.3-42.7). On subgroup analysis, pooled rates of treatment responders and bleeding events seemed similar between low molecular weight heparin, vitamin K antagonists, and direct oral anticoagulants.

Conclusions

Our study demonstrated that anticoagulation is effective and safe in the treatment of PVT in patients with cirrhosis. Owing to the comparable outcomes, direct oral anticoagulants may be considered as first-line treatment, depending on patient preferences.

Recent developments in the field of vascular liver diseases

Knowledge in the field of vascular liver disease is continuously expanding. The present update will discuss recent data on i) the Abernethy malformation in adults; ii) portal vein thrombosis in cirrhosis; iii) advancing expertise in recanalization of the portal vein and iv) experience in using direct oral anticoagulants in the field of vascular liver disease.

Anticoagulation in Cirrhosis and Portal Vein Thrombosis Is Safe and Improves Prognosis in Advanced Cirrhosis

BACKGROUND

The role of portal vein thrombosis (PVT) in the natural history of cirrhosis is controversial.

AIMS

We analyzed the safety and effect of anticoagulant therapy (AT) on PVT recanalization and orthotopic liver transplant (OLT)-free survival.

METHODS

Eighty consecutive patients from a prospective registry of cirrhosis and non-tumoral PVT at a tertiary center were analyzed. AT effect on PVT recanalization and OLT-free survival was determined by time-dependent Cox regression analysis.

RESULTS

Average MELD score was 15 ± 7. Portal hypertension-related complications at PVT diagnosis were present in 65 (81.3%) patients. Isolated portal vein trunk/branch thrombosis was present in 53 (66.3%) patients. AT was started in 37 patients. AT was stopped in 17 (45.9%) patients, in 4 (10.8%) due to bleeding events. No variceal bleeding occurred while on AT. Anticoagulation was restarted in 6/17 (35.2%) patients due to rethrombosis. In 67 patients with adequate follow-up imaging, AT significantly increased the rate of PVT recanalization compared with those who did not receive anticoagulation [51.4% (18/35) vs 6/32 (18.8%), p = 0.005]. OLT-free survival after a median follow-up of 25 (1-146) months was 32 (40%). Although there was no significant effect of AT on overall OLT-free survival, OLT-free survival was higher among patients with MELD ≥ 15 receiving AT compared to those who did not (p = 0.011). Baseline MELD at PVT detection independently predicted PVT recanalization (HR 1.11, 95% CI 1.01-1.21, p = 0.027) and mortality/OLT (HR 1.12, 95% CI 1.05-1.19, p < 0.001).

CONCLUSIONS

Although AT did not improve overall OLT-free survival, it was associated with higher survival in advanced cirrhosis. Anticoagulation increased PVT recanalization and should be maintained after PVT recanalization to avoid rethrombosis.

Portal vein thrombosis in cirrhosis: Why a well-known complication is still matter of debate

Portal vein thrombosis (PVT) represents a well-known complication during the natural course of liver cirrhosis (LC), ranging from asymptomatic cases to life-threating conditions related to portal hypertension and hepatic decompensation. Portal flow stasis, complex acquired hypercoagulable disorders and exogenous factors leading to endothelial dysfunction have emerged as key factors for PVT development. However, PVT occurrence remains unpredictable and many issues regarding its natural history, prognostic significance and treatment are still elusive. In particular although spontaneous resolution or disease stability occur in most cases of PVT, factors predisposing to disease progression or recurrence after spontaneous recanalization are not clarified as yet. Moreover, PVT impact on LC outcome is still debated, as PVT may represent itself a consequence of liver fibrosis and hepatic dysfunction progression. Anticoagulation and transjugular intrahepatic portosystemic shunt are considered safe and effective in this setting and are recommended in selected cases, even if the safer therapeutic option and the optimal therapy duration are still unknown. Nevertheless, their impact on mortality rates should be addressed more extensively. In this review we present the most debated questions regarding PVT, whose answers should come from prospective cohort studies and large sample-size randomized trials.

Portal vein thrombosis and liver cirrhosis: Long-term anticoagulation is effective and safe

BACKGROUND AND AIMS

Portal vein thrombosis (PVT) is a common complication of liver cirrhosis. Anticoagulation therapy is efficient, but is associated with potentially severe side-effects, especially bleeding episodes. It is therefore still unclear which patients will benefit from anticoagulation, and for what duration. The aim of the present study was to retrospectively analyse our single centre experience on long-term anticoagulation in patients presenting a PVT, complicating cirrhosis.

METHODS

Data of 40 cirrhotic patients with PVT treated by anticoagulation therapy from June 2003 to May 2018 were collected. Regular imaging was performed to monitor the outcome of PVT. The hemorrhagic complications and the recurrence of the PVT after anticoagulation withdrawal were also analyzed.

RESULTS

The median follow-up under anticoagulation therapy was 33.7 months. Complete (57.5%) or partial (25.0%) recanalization of PVT was observed. Fifteen bleeding episodes (37.5%) occurred in our population, related to portal hypertension in 7 (46.7%). Eleven (73.3%) patients required hospitalization and eight (53.3%) required blood transfusion. No patient died from bleeding complication. Anticoagulation was stopped in 10 patients (25.0%), because of regression of PVT in 5 patients or a haemorrhagic episode in 5 patients. Among those 10 patients, 7 had a recurrence or extension of the initial PVT.

CONCLUSIONS

Our results confirm that anticoagulation allows a recanalization of PVT complicating cirrhosis in the majority of the cases, is associated with non-severe bleeding complications, and can be maintained for a long duration in order to avoid recurrence.

Diagnosis, Development, and Treatment of Portal Vein Thrombosis in Patients With and Without Cirrhosis

Portal vein thrombosis unrelated to solid malignancy is common in patients with cirrhosis, but less frequently observed in patients without cirrhosis. Prompt diagnosis and management of acute symptomatic portal vein thrombosis are essential. Failure to detect and treat thromboses can result in mesenteric ischemia, chronic cavernous transformation, and complications of portal hypertension. In patients with cirrhosis, development of portal vein thrombosis is often insidious and remains undetected until its incidental detection. Management of portal vein thrombosis in patients with cirrhosis is more controversial. However, there are data to support treatment of specific patients with anticoagulation agents. We review the common and distinct features of portal vein thromboses in patients without liver tumors, with and without cirrhosis.

Anticoagulation and Transjugular Intrahepatic Portosystemic Shunting for Treatment of Portal Vein Thrombosis in Cirrhosis: A Systematic Review and Meta-Analysis

Portal vein thromboses (PVTs) are associated with hepatic decompensation, worse survival, and worse liver transplant outcomes. We evaluated the impact of anticoagulation (AC) and transjugular intrahepatic portosystemic shunting (TIPS) on recanalization and mortality in patients with cirrhosis and PVT. Systematic search of electronic databases was performed. Clinical trials and observational studies that evaluated primary outcomes of recanalization and survival in patients with cirrhosis having PVT treated with AC or TIPS were included. Risk of bias was assessed. Summary odds ratios (ORs) for pooled data from the included studies were generated using a random effects model. A total of 505 studies were screened for inclusion. After review, 7 studies were ultimately included. Data from 327 patients in total were evaluated. Overall, treatment with either AC or TIPS resulted in partial or complete recanalization (OR: 4.56 [95% confidence interval, CI: 2.46-8.47]) but did not significantly impact mortality (OR: 0.57 [95% CI: 0.21-1.57]). The summary OR of AC for recanalization was 6.00 (95% CI: 2.38-15.07). The summary OR of TIPS for recanalization was 3.80 (95% CI: 1.47-9.83). The summary OR of mortality in patients treated with AC for PVT was 0.28 (95% CI: 0.08-0.95). The mortality summary OR was 1.10 (95% CI 0.23-5.16) in patients who underwent TIPS. There was insufficient data to assess complications such as hepatic encephalopathy or bleeding. Both AC and TIPS have a significant effect on recanalization. Anticoagulation appears to have a protective effect on mortality that is not seen with TIPS. More studies with control groups are need.

A prediction model for successful anticoagulation in cirrhotic portal vein thrombosis

BACKGROUND AND OBJECTIVE

Portal vein thrombosis (PVT) is a common complication in cirrhosis, and when complete, it increases morbidity and mortality in liver transplant candidates. The aim of the study was to assess the hemostatic status, as well as clinical characteristics of thrombus and patients, as predictors of therapeutic efficacy of anticoagulation for the treatment of PVT in cirrhotics.

PATIENTS AND METHODS

Patients with cirrhosis consecutively treated for PVT with enoxaparin were enrolled. All patients underwent evaluation of coagulation status and thrombophilia screening. Thrombus characteristics and extension were evaluated at baseline and during follow-up. Anticoagulation was continued until recanalization or up to 12 months. Variables correlated with the response to anticoagulation were used to create a predictive score that was validated in an external multicenter cohort.

RESULTS

A total of 65 patients were included and had partial PVT in most cases (72%). Treatment with enoxaparin resulted in an overall response rate of 66% (43/65) after a median time of 4.4 months and 76% (33/43) within the first 6 months. At multivariate analysis, efficacy of anticoagulation correlated with the severity of liver disease, complete verus partial PVT, age of the thrombus, and time interval from treatment start (<6 months). The areas under the curve of the statistical model for predicting the response to anticoagulation were 0.84 and 0.76 for the training (n=65) and validation (n=60) cohorts, respectively.

CONCLUSION

Early diagnosis and early treatment are key factors for the successful management of PVT in cirrhosis, so that screening of PVT and prompt start of anticoagulant treatment should be mandatory.

Coagulation, Microenvironment and Liver Fibrosis

Fibrosis is the main consequence of any kind of chronic liver damage. Coagulation and thrombin generation are crucial in the physiological response to tissue injury; however, the inappropriate and uncontrolled activation of coagulation cascade may lead to fibrosis development due to the involvement of several cellular types and biochemical pathways in response to thrombin generation. In the liver, hepatic stellate cells and sinusoidal endothelial cells orchestrate fibrogenic response to chronic damage. Thrombin interacts with these cytotypes mainly through protease-activated receptors (PARs), which are expressed by endothelium, platelets and hepatic stellate cells. This review focuses on the impact of coagulation in liver fibrogenesis, describes receptors and pathways involved and explores the potential antifibrotic properties of drugs active in hemostasis in studies with cells, animal models of liver damage and humans.

The Role of Anticoagulation in Treating Portal Hypertension

PURPOSE OF REVIEW

To revise experimental and clinical data supporting a less traditional role of anticoagulation for treating portal hypertension in patients with cirrhosis.

RECENT FINDINGS

Portal hypertension is the main driver of complications such as ascites, variceal hemorrhage, and hepatic encephalopathy, with inflammation as a key component. The traditional view of cirrhosis as a pro-hemorrhagic condition has recently changed, prothrombotic complications being recognized as frequently as the hemorrhagic ones. Several data indicate a close relationship between inflammation, prothrombotic status, worsening of hepatic fibrosis, and portal hypertension both in animal models and in patients with chronic liver disease. These findings indicate that anticoagulation may represent a potent tool to act on fibrogenesis and therefore consequently to treat portal hypertension. All anticoagulants have good to optimal safety profiles and can be used in patients with advanced chronic liver disease with confidence.

SUMMARY

Anticoagulation has a role as a pleiotropic treatment of portal hypertension in cirrhosis.