Natural history and predictors associated with the evolution of portal venous system thrombosis in liver cirrhosis

Portal vein thrombosis: diagnosis, management, and endpoints for future clinical studies

Portal vein thrombosis (PVT) refers to the development of a non-malignant obstruction of the portal vein, its branches, its radicles, or a combination. This Review first provides a comprehensive overview of all aspects of PVT, namely the specifics of the portal venous system, the risk factors for PVT, the pathophysiology of portal hypertension in PVT, the interest in non-invasive tests, as well as therapeutic approaches including the effect of treating risk factors for PVT or cause of cirrhosis, anticoagulation, portal vein recanalisation by interventional radiology, and prevention and management of variceal bleeding in patients with PVT. Specific issues are also addressed including portal cholangiopathy, mesenteric ischaemia and intestinal necrosis, quality of life, fertility, contraception and pregnancy, and PVT in children. This Review will then present endpoints for future clinical studies in PVT, both in patients with and without cirrhosis, agreed by a large panel of experts through a Delphi consensus process. These endpoints include classification of portal vein thrombus extension, classification of PVT evolution, timing of assessment of PVT, and global endpoints for studies on PVT including clinical outcomes. These endpoints will help homogenise studies on PVT and thus facilitate reporting, comparison between studies, and validation of future studies and trials on PVT.

Natural history of portal vein thrombosis in cirrhosis: A systematic review with meta-analysis

BACKGROUND AND AIM

Progression of liver disease in cirrhosis is associated with an increased incidence of portal vein thrombosis (PVT) in cirrhosis. However, evidence suggests that spontaneous recanalization of PVT may occur even without anti-thrombotic therapy. Thus, the present meta-analysis was conducted to study the natural history of PVT in cirrhosis, facilitating decisions regarding anticoagulation.

METHODS

Three electronic databases were searched from 2000 to August 2022 for studies reporting the outcome of PVT in cirrhotics without anticoagulation. The pooled proportions with their 95% confidence intervals (CIs) were calculated using a random-effect model.

RESULTS

A total of 26 studies (n = 1441) were included in the final analysis. Progression of PVT on follow-up was seen in 22.2% (95% CI 16.1-28.4), while 77.7% (95% CI 71.6-83.9) remained non-progressive (improved or stable). The most common outcome was a stable PVT with a pooled event rate of 44.6% (95% CI 34.4-54.7). The pooled rates of regression and complete recanalization of PVT in cirrhotics were 29.3% (95% CI 20.9-37.7) and 10.4% (95% CI 5.0-15.8), respectively. On follow-up after improvement, pooled recurrence rate of PVT was 24.0% (95% CI 14.7-33.4). MELD score, and presence of ascites had a negative association, while a longer follow-up duration had positive association with PVT regression.

CONCLUSION

Approximately 25% of the cases of PVT in cirrhosis are progressive, 30% cases improve, and 45% remain stable. Future studies are needed to analyze the predictors of spontaneous regression.

Understanding the pathogenesis of portal vein thrombosis in liver cirrhosis: We are still on the way

Portal vein thrombosis (PVT) is a common complication of liver cirrhosis. In this issue of the Journal of Clinical Ultrasound: Sonography and other Imaging Techniques, a systematic review and meta‐analysis by Giri et al assessed the role of portal system hemodynamics for predicting the presence and development of PVT in liver cirrhosis.

Nomogram for Predicting Postoperative Portal Venous Systemic Thrombosis in Patients with Cirrhosis Undergoing Splenectomy and Esophagogastric Devascularization

OBJECTIVES

The aim of the study is to develop a nomogram for predicting postoperative portal venous systemic thrombosis (PVST) in patients with cirrhosis undergoing splenectomy and esophagogastric devascularization.

METHODS

In total, 195 eligible patients were included. Demographic characteristics were collected, and the results of perioperative routine laboratory investigations and ultrasound examinations were also recorded. Blood cell morphological traits, including the red cell volume distribution width (RDW), mean platelet volume, and platelet distribution width, were identified. Univariate and multivariate logistic regressions were implemented for risk factor filtration, and an integrated nomogram was generated and then validated using the bootstrap method.

RESULTS

A color Doppler abdominal ultrasound examination on a postoperative day (POD) 7 (38.97%) revealed that 76 patients had PVST. The results of the multivariate logistic regression suggested that a higher RDW on POD3 (RDW3) (odds ratio (OR): 1.188, 95% confidence interval (CI): 1.073-1.326), wider portal vein diameter (OR: 1.387, 95% CI: 1.203-1.642), history of variceal hemorrhage (OR: 3.407, 95% CI: 1.670-7.220), and longer spleen length (OR: 1.015, 95% CI: 1.001-1.029) were independent risk parameters for postoperative PVST. Moreover, the nomogram integrating these four parameters exhibited considerable capability in PVST forecasting. The nomogram's receiver operating characteristic curve reached 0.83 and achieved a sensitivity and specificity of 0.711 and 0.848, respectively, at its cutoff. The nomogram's calibration curve demonstrated that it was well calibrated.

CONCLUSION

The nomogram exhibited excellent performance in PVST prediction and might assist surgeons in identifying vulnerable patients and administering timely prophylaxis.

Epidemiology of portal vein thrombosis in liver cirrhosis: A systematic review and meta-analysis

BACKGROUND

Portal vein thrombosis (PVT) may be associated with negative outcomes in patients with liver cirrhosis. However, the prevalence and incidence of PVT in liver cirrhosis are heterogeneous among studies and have not been sufficiently determined yet.

METHODS

The PubMed, EMBASE, and Cochrane Library databases were searched. Eligible studies would explore the prevalence and/or incidence of PVT in liver cirrhosis without hepatocellular carcinoma or abdominal surgery. Pooled proportion with 95% confidence interval (CI) was calculated using a random-effect model. Factors associated with the presence/occurrence of PVT were also extracted.

RESULTS

Among the 8549 papers initially identified, 74 were included. Fifty-four studies explored the prevalence of PVT in liver cirrhosis with a pooled prevalence of 13.92% (95%CI=11.18-16.91%). Based on cross-sectional data, Child-Pugh class B/C, higher D-dimer, ascites, and use of non-selective beta-blockers (NSBBs) were associated with the presence of PVT in liver cirrhosis. Twenty-three studies explored the incidence of PVT in liver cirrhosis with a pooled incidence of 10.42% (95%CI=8.16-12.92%). Based on cohort data, Child-Pugh class B/C, higher model of end-stage liver disease score, higher D-dimer, lower platelets count, decreased portal flow velocity, ascites, use of NSBBs, and moderate or high-risk esophageal varices could predict the occurrence of PVT in liver cirrhosis.

CONCLUSION

Approximately one seventh of cirrhotic patients have PVT, and one tenth will develop PVT. Progression of liver cirrhosis and portal hypertension seems to be in parallel with the risk of PVT. Prospective studies with detailed information about classification and extension of PVT in liver cirrhosis are needed.

Impact of Asymptomatic Superior Mesenteric Vein Thrombosis on the Outcomes of Patients with Liver Cirrhosis

BACKGROUND

 The impact of asymptomatic superior mesenteric vein (SMV) thrombosis on the outcomes of cirrhotic patients remains uncertain.

METHODS

 Nonmalignant cirrhotic patients who were consecutively admitted between December 2014 and September 2021 and underwent contrast-enhanced computed tomography/magnetic resonance imaging scans were screened. Portal venous system thrombosis (PVST) was identified. Death and hepatic decompensation were the outcomes of interest. Nelson-Aalen cumulative risk curve analysis and competing risk regression analysis were performed to evaluate the impact of asymptomatic SMV thrombosis and portal vein thrombosis (PVT) on the outcomes.

RESULTS

 Overall, 475 patients were included, of whom 67 (14.1%) had asymptomatic SMV thrombosis, 95 (20%) had PVT, and 344 (72.4%) did not have any PVST. Nelson-Aalen cumulative risk curve analyses showed that the cumulative incidences of death (p = 0.653) and hepatic decompensation (p = 0.630) were not significantly different between patients with asymptomatic SMV thrombosis and those without PVST, but the cumulative incidences of death (p = 0.021) and hepatic decompensation (p = 0.004) were significantly higher in patients with PVT than those without PVST. Competing risk regression analyses demonstrated that asymptomatic SMV thrombosis was not a significant risk factor for death (subdistribution hazard ratio [sHR] = 0.89, p = 0.65) or hepatic decompensation (sHR = 1.09, p = 0.63), but PVT was a significant risk factor for death (sHR = 1.56, p = 0.02) and hepatic decompensation (sHR = 1.50, p = 0.006). These statistical results remained in competing risk regression analyses after adjusting for age, sex, and Child-Pugh score.

CONCLUSIONS

 Asymptomatic SMV thrombosis may not influence the outcomes of cirrhotic patients. The timing of intervention for asymptomatic SMV thrombosis in liver cirrhosis should be further explored.

Anticoagulation and Vessel Recanalization in Cirrhotic Patients with Splanchnic Vein Thrombosis: A Multidisciplinary "Real Life" Experience

Background and Aim

Splanchnic vein thrombosis (SVT) is a potentially life-threatening complication of liver cirrhosis. This study aimed to evaluate the impact of a multi-disciplinary approach and early anticoagulation therapy (AT) on bleeding/thrombotic events, recanalization rates and outcome of cirrhotic patients with SVT.

Methods

This is a single-center, registry-based cohort study. Over 17 years, 149 SVT patients were enrolled and prospectively evaluated. Regarding cirrhotic-SVT, a pre-specified algorithm, guiding initial posology of AT and follow-up visits schedule, was performed. Major bleeding (MB), thrombotic events, functional liver scores and all cause-mortality were investigated. Efficacy of AT was evaluated by radiological imaging.

Results

In cirrhotic-SVT, the incidence rate of MB was 8.4 per 100 patient-year (95% CI, 3.83–15.97), while the incidence rate of thrombosis was 5.6 per 100 patient-year (95% CI, 2.05–12.2). In incidental SVT treated with AT, MB incidence was 6.5 per 100 patient-year (95% CI: 2.8–12.82), while in symptomatic SVT was 2.2 per 100 patient-year (95% CI: 0.25–8.02). All thrombotic recurrences occurred in incidental SVT (7.7 per 100 patient-years; 95% CI, 3.71–14.26). Overall survival was significantly higher in patients who had at least a partial recanalization (p < 0.01) and partial/total recanalization was independently associated with improved MELD score at multivariate analysis (HR 2.62, 95% CI 1.1–6.47, p = 0.03).

Conclusion

In cirrhotic SVT patients, partial or total resolution of thrombosis ameliorates liver function and is associated with higher overall survival. A multidisciplinary approach together with radiological follow-up at pre-fixed time improves patient selection and monitoring.

Evolution of Nonmalignant Portal Vein Thrombosis in Liver Cirrhosis: A Pictorial Review

Portal vein thrombosis (PVT) is a common complication in liver cirrhosis, especially in advanced cirrhosis. It may be related to a higher risk of liver-related events and liver function deterioration. Imaging examinations can not only provide an accurate diagnosis of PVT, such as the extent of thrombus involvement and the degree of lumen occupied, but also identify the nature of thrombus (i.e., benign/malignant and acute/chronic). Evolution of PVT, mainly including development, recanalization, progression, stability, and recurrence, could also be assessed based on the imaging examinations. This article briefly reviews the pathophysiology, diagnosis, classification, and evolution of PVT with an emphasis on their computed tomography imaging features.

No Association of Homocysteine, Anticardiolipin Antibody, and Anti-β2 Glycoprotein I Antibody With Portal Venous System Thrombosis in Liver Cirrhosis

Portal venous system thrombosis (PVST), a common complication of liver cirrhosis, is closely associated with thrombophilia. To explore the association of homocysteine (Hcy), anticardiolipin antibody (aCL), and anti-β2 glycoprotein I antibody (aβ₂GPI), which are possible thrombophilic factors, with PVST in liver cirrhosis. Overall, 654 non-malignant patients (219 with and 435 without liver cirrhosis) admitted between January 2016 and June 2020 were retrospectively evaluated. Presence of PVST, degree of main portal vein (MPV) thrombosis, and clinically significant PVST were identified. Hcy level, hyperhomocysteinemia (HHcy), aCL positivity, and aβ₂GPI positivity were compared according to the presence of liver cirrhosis and PVST. Positive aβ₂GPI was significantly more frequent in patients with liver cirrhosis than those without, but Hcy level and proportions of HHcy and positive aCL were not significantly different between them. PVST could be evaluated in 136 cirrhotic patients. Hcy level [10.57 μmol/L (2.71-56.82) versus 9.97 μmol/L (2.05-53.44); P = 0.796] and proportions of HHcy [4/44 (9.1%) versus 13/81 (16.0%); P = 0.413] and positive aCL [1/23 (4.3%) versus 10/52 (19.2%); P = 0.185] and aβ₂GPI [9/23 (39.1%) versus 21/52 (40.4%); P = 0.919] were not significantly different between cirrhotic patients with and without PVST. There was still no significant association of Hcy level, HHcy, aCL, or aβ₂GPI with PVST based on Child-Pugh classification, MPV thrombosis >50%, and clinically significant PVST. Hcy, aCL, and aβ₂GPI may not be associated with PVST in liver cirrhosis, suggesting that routine screening for Hcy, aCL, and aβ₂GPI should be unnecessary in such patients.