Portal vein thrombosis and renal dysfunction: a national comparative study of liver transplant recipients for NAFLD versus alcoholic cirrhosis

Unusual-site thrombosis in patients with hazardous alcohol use: a narrative review

AIMS AND METHODS

Hazardous alcohol use poses an increasing public health issue worldwide and it manifests as excessive consumption (acute or chronic), which may lead to addiction. The risk of alcohol-related pathologies correlates with the patterns of intake and increases with the amount of alcohol consumed. While the effects of alcohol consumption on ischemic stroke and ischemic heart disease are well documented, the impact on venous thromboembolism is less clear. Conflicting studies have reported that alcohol may be a risk factor for, or have a protective role against venous thromboembolism. Our narrative review aimed to assess the risk of unusual-site venous thrombosis in individuals with hazardous alcohol use, as it may stem from alcohol-related organ damage (e.g. liver cirrhosis, pancreatitis) as well as provide some suggestions for physicians.

RESULTS

There appears to be a correlation between hazardous alcohol use and unusual-site thrombosis, though the underlying mechanisms are largely still unknown.

CONCLUSION

In subjects with hazardous alcohol use complicated by alcohol-related organ damage, physicians should be vigilant for potential thrombotic symptoms, and be prepared to diagnose and promptly initiate appropriate anticoagulation therapy.

Post-Liver Transplant Outcomes: A Comparative Study of 6 Predictive Models

Background

We compared the performance of the Liver Transplant Risk Score (LTRS) with the survival outcomes following liver transplantation (SOFT), pretransplant SOFT (P-SOFT), Balance of Risk Score (BAR), donor-age and model for end-stage liver disease (D-MELD), and Organ Procurement and Transplantation Network Risk Prediction Score (ORPS) for the prediction of 90-d mortality, 1-y mortality, and 5-y survival after first-time liver transplantation (LT).

Methods

A retrospective analysis of the Scientific Registry of Transplant Recipients was conducted using data collected between 2002 and 2021.

Results

A total of 82 696 adult LT recipients with a median age of 56 y were included. The area under the curve for 90-d mortality were 0.61, 0.66, 0.65, 0.61, 0.58, and 0.56 for the LTRS, SOFT, P-SOFT, BAR, D-MELD, and ORPS, respectively (all pairwise comparisons: P < 0.05). The area under the curve for 1-y mortality were 0.60, 0.63, 0.62, 0.59, 0.60, 0.57, and 0.59 for the LTRS, SOFT, P-SOFT, BAR, D-MELD, and ORPS, respectively (all pairwise comparisons: P < 0.05). The c-statistics for 5-y survival were not statistically significant among the models. For 90-d mortality, 1-y mortality, and 5-y survival, the correlation coefficients between the LTRS and P-SOFT (the 2 models requiring only preoperative parameters) were 0.90. 0.91, and 0.81, respectively (P < 0.01).

Conclusions

None of the predictive models demonstrated sufficient precision to reliably identify LT recipients who died within 90 d and 1 y after LT. However, all models exhibited strong capabilities in perioperative risk stratification. Notably, the P-SOFT and LTRS models, the 2 models that can be calculated using only preoperative data, proved to be valuable tools for identifying candidates at a significant risk of poor outcomes.

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.

Impact of Cirrhosis Etiology on the Risk for Venous Thromboembolism

BACKGROUND

Cirrhosis is associated with an increased risk for both bleeding and venous thromboembolic (VTE) complications. The data regarding the impact of etiology of cirrhosis on VTE risk is poorly understood.

METHODS

In this retrospective observational analysis of the US Nationwide readmissions database 2019, we identified hospitalized patients who had cirrhosis from alcohol, viral, or nonalcoholic steatohepatitis (NASH) etiologies. We identified patients who had acute VTE, chronic/history of VTE, and portal venous thrombosis (PVT). Overall VTE risk was defined as the composite of acute and chronic VTE or PVT. The impact of etiology of cirrhosis on the crude and risk adjusted rates of VTE and PVT was studied.

RESULTS

Of 432,383 patients with cirrhosis, 41.4% patients had NASH-cirrhosis, 39.7% had alcohol-related cirrhosis, and 18.9% had viral cirrhosis. The overall VTE rate was highest in patients with NASH cirrhosis (10.8%) followed by viral cirrhosis (9.7%) and alcohol-related cirrhosis (7.5%; P < 0.001). Similar results were observed for acute and chronic VTE. After risk adjustment, patients with NASH (OR 1.48 95% CI 1.42-1.54) and viral cirrhosis (OR 1.22 95% CI 1.17-1.29) had significantly higher overall VTE risk compared with alcohol-related cirrhosis. When separately evaluated, the adjusted risk for acute and chronic VTE was similar between patients with alcohol-related and viral cirrhosis but higher with NASH cirrhosis. PVT rate was highest with viral cirrhosis (4.3%) followed by NASH (2.8%) and alcohol-related cirrhosis (2.4%; P < 0.001). The adjusted risk of PVT was higher with viral (OR 1.61 95% CI 1.50-1.72) and NASH cirrhosis (OR 1.41 95% CI 1.31-1.52).

CONCLUSION

NASH cirrhosis was associated with a higher VTE risk compared with alcohol-related and viral etiologies. As NASH cirrhosis increases in prevalence as the major etiology of cirrhosis, it is important to understand the increased VTE risk associated with this condition to improve management strategies and patient outcomes.

Prevalence of portal vein thrombosis in non-alcoholic fatty liver disease: a meta-analysis of observational studies

Portal vein thrombosis (PVT) is a common complication of cirrhosis as a result of portal hypertension and modification in the hemostatic balance. Accumulating evidence now suggests that patients with non-alcoholic fatty liver disease (NAFLD), especially those with advanced forms, have an increased risk of PVT. Hence, we performed a meta-analysis of observational studies to estimate the overall prevalence of PVT in patients with NAFLD and its advanced forms compared with patients with advanced liver diseases from other etiologies. We systematically searched PubMed, Scopus and Web of Science databases from the inception date to December 30th 2022, using predefined keywords, to identify observational studies. Meta-analysis was performed using random-effects modeling. We included five observational studies for a total of 225,571 patients. Of these, 26,840 (11.9%) patients had NAFLD, whereas the PVT prevalence was 8.5% (n = 2,280). When compared with patients with advanced liver diseases from other etiologies, patients with NAFLD and its advanced forms had a higher risk of prevalent PVT (OR 1.34, 100% CI 1.07-1.67 p < 0,01). The between-study heterogeneity was substantial (I2 = 88%). This meta-analysis suggests that compared with patients with advanced liver diseases from other etiologies, patient with NAFLD and its advanced forms had a higher risk of prevalent PVT. Further research is required to understand the complex link between NAFLD/NASH and PVT development.

Natural history of NASH cirrhosis in liver transplant waitlist registrants

BACKGROUND AND AIMS

Non-alcoholic steatohepatitis (NASH) cirrhosis is rapidly growing as an indication for liver transplant(ation) (LT). However, the natural history of NASH cirrhosis among LT waitlist registrants has not been established. The present study aimed to define the natural history of NASH cirrhosis using the Scientific Registry of Transplant Recipients database.

METHODS

The study cohort comprised patients registered on the LT waitlist between 1/1/2016 to 12/31/2021. The primary outcomes included probability of LT and waitlist mortality, comparing NASH (n = 8,120) vs. non-NASH (n = 21,409) cirrhosis.

RESULTS

Patients with NASH cirrhosis were listed with lower model for end-stage liver disease (MELD) scores despite bearing a greater burden of portal hypertension, especially at lower MELD scores. The overall transplant probability in LT waitlist registrants with NASH [vs. non-NASH] cirrhosis was significantly lower at 90 days (HR 0.873, p <0.001) and 1 year (HR 0.867, p <0.001); this was even more pronounced in patients with MELD scores >30 (HR 0.705 at 90 days and HR 0.672 at 1 year, p <0.001 for both). Serum creatinine was the key contributor to MELD score increases leading to LT among LT waitlist registrants with NASH cirrhosis, while bilirubin was in patients with non-NASH cirrhosis. Finally, waitlist mortality at 90 days (HR 1.15, p <0.001) and 1 year (1.25, p <0.001) was significantly higher in patients with NASH cirrhosis compared to those with non-NASH cirrhosis. These differences were more pronounced in patients with lower MELD scores at the time of LT waitlist registration.

CONCLUSIONS

LT waitlist registrants with NASH cirrhosis are less likely to receive a transplant compared to patients with non-NASH cirrhosis. Serum creatinine was the major contributor to MELD score increases leading to LT in patients with NASH cirrhosis.

IMPACT AND IMPLICATIONS

This study provides important insights into the distinct natural history of non-alcoholic steatohepatitis (NASH) cirrhosis among liver transplant (LT) waitlist registrants, revealing that patients with NASH cirrhosis face lower odds of transplantation and higher waitlist mortality than those with non-NASH cirrhosis. Our study underscores the significance of serum creatinine as a crucial contributor to model for end-stage liver disease (MELD) score in patients with NASH cirrhosis. These findings have substantial implications, emphasizing the need for ongoing evaluation and refinement of the MELD score to more accurately capture mortality risk in patients with NASH cirrhosis on the LT waitlist. Moreover, the study highlights the importance of further research investigating the impact of the implementation of MELD 3.0 across the US on the natural history of NASH cirrhosis.

Risk Factors of Portal Vein Thrombosis in Patients with Different Child-Pugh Classes Liver Cirrhosis

Aim: to evaluate the frequency of portal vein thrombosis (PVT) and build predictive models of the development of PVT for patients with liver cirrhosis (LC) of A and B/C classes by Child-Pugh.

Materials and methods. Research design is a case-control. The Case group included 130 patients with newly diagnosed PVT not caused by invasive hepatocellular carcinoma (HCC); 29 patients were assigned to class A, 101 patients were assigned to class B/C. From the database of cirrhotic patients without PVT 60 Controls for class A and 205 for B/C were selected using sratified randomization by sex, age and etiology of cirrhosis. The Mann-Whitney U-test and Pearson's chi-squared test were used to compare the groups. Odds ratios (OR) and 95 % confidence intervals (95 % CI) were calculated. Logistic regression models are constructed with the separation of the sample into training and test (0.7; 0.3). The operational characteristics of the models were calculated on the test sample; ROC analysis was carried out, the area under the ROC curve (AUC) was calculated.

Results. The overall frequency of PVT was 4.1 % (95 % CI 2.7-5.8 %) in class A and 10.4 % (95 % CI 8.5-12.5 %) class B/C. Patients with class A and B/C PVT differed from the corresponding controls by more severe portal hypertension: the frequency of bleeding / number of interventions on varices compared with the control were 41/45 % vs. 7/8 % (p < 0.001) for class A and 25.7/30.7 % vs. 16.1/16.1 % (p < 0.05) for class B/C, ascites frequency was 24 % vs. 8 % (p < 0.05) for class A and 89.1 % vs. 68.3 % (p < 0.001) for class B/C. The cutoff by the portal vein diameter was the same for both classes — 13.4 mm; the spleen length was similar and amounted 17.5 mm for class A, 17.1 mm for class B/C. Patients with PVT differed from the corresponding controls by neutrophil-to-lymphocyte ratio: class A 2.33 (1.82; 3.61) vs. 1.76 (1.37; 2.20), p < 0.01, class B/C 2.49 (1.93; 3.34) vs. 2.15 (1.49; 3.26), p < 0.05. Patients of class B/C had a higher incidence of newly diagnosed malignant tumors - 23.8% (primarily HCC that does not invade the portal vein), compared with control and cases of class A - 6.3 % and 3 % (p < 0.05), respectively. The best model for class A included variceal bleeding, ascites, portal vein diameter, absolute number of neutrophils, for class B — ascites, spleen length, portal vein diameter, malignant tumors / local factors; sensitivity, specificity, accuracy and AUC were 79.3 %, 90 %, 86.5 %, 0.897 and 73.3 %, 68.3 %, 69.9 %, 0.789, respectively.

Conclusion. Independently of the Child-Pugh class of LC, the main risk factor for PVT is severe portal hypertension.

The Pathophysiology of Portal Vein Thrombosis in Cirrhosis: Getting Deeper into Virchow's Triad

Portal vein thrombosis (PVT) is a common complication among patients with cirrhosis. However, its pathophysiology is not well established and there are currently very few predictive factors, none of which are actually useful, from a clinical perspective. The contribution of each of the vertices of Virchow’s triad, e.g., blood hypercoagulability, blood flow, and portal vein endothelial damage in the development of PVT is not clear. In this review, we aim to recapitulate the latest studies on the field of PVT development in order to understand its mechanisms and discuss some of the future directions in the study of this important complication of cirrhosis.