Evidence that low protein C contributes to the procoagulant imbalance in cirrhosis

Cirrhosis Progression Is Not Associated with Clinically Significant Alterations in Global Hemostasis Assessed by Thromboelastography

(1) Background: Cirrhosis is associated with frequent alterations in standard coagulation tests that do not adequately reflect hemostasis. Thromboelastography provides a global assessment of coagulation and evaluates the functional status of clotting factors, fibrinogen, platelets, and fibrinolysis. The study aimed to assess whether liver disease severity leads to progressive alterations in the thromboelastography-based assessment of coagulation. (2) Methods: Consecutive patients with cirrhosis and abnormal standard coagulation tests (at least one of International Normalized Ratio > 2, platelet count < 50 × 103/µL, fibrinogen < 200 mg/dL) were analyzed using native thromboelastography. (3) Results: A total of 106 patients were included, of whom 69 (65.1%) had a normal thromboelastography. While the standard coagulation tests were significantly worse in patients in the Child C group (n = 62, 58.5%) than in patients staged in Child A and B, no significant differences existed between any of the thromboelastography variables. Of the 50 patients (47.1%) with an International Normalized Ratio > 2, only two patients (4%) had features of hypocoagulation, while 26% had features of hypercoagulability on thromboelastography. Patients with a platelet count < 50 × 103/µL had significantly lower platelet function as assessed by thromboelastography, yet only eight patients (20%) met the criteria for platelet transfusion. A thromboelastography-based transfusion protocol might lead to a 94.6% reduction in blood product transfusion indications in a simulation where the included patients would require interventional procedures. (4) Conclusion: Standard coagulation tests showed a poor correlation with thromboelastography. Based on thromboelastography, patients with severe, decompensated liver disease have a preserved hemostasis balance despite abnormal standard coagulation tests. Therefore, standard coagulation tests should not be used to guide the administration of blood products in patients with cirrhosis.

The Molecular Mechanisms of Portal Vein Thrombosis in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) represents the sixth most diagnosed cancer worldwide and is the second leading cause of cancer-related death in the world. The association of HCC and portal vein thrombosis (PVT) represents an advanced stage of the tumor. PVT has a prevalence of about 25-50% in HCC, determining poor prognosis and a remarkable reduction in therapeutic perspectives in these patients, leading to severe complications such as ascites, metastasis, an increase in portal hypertension and potentially fatal gastrointestinal bleeding. The aim of this review is to evaluate the molecular mechanisms that are at the basis of PVT development, trying to evaluate possible strategies in the early detection of patients at high risk of PVT.

Prothrombin conversion and thrombin decay in patients with cirrhosis-role of prothrombin and antithrombin deficiencies

BACKGROUND

Thrombin generation (TG) in the presence of thrombomodulin (TG-TM) in the plasma of patients with cirrhosis (PWC) is tilted toward a hypercoagulable phenotype. Low protein C and elevated factor VIII levels play a role, but other determinants, such as the prothrombin/antithrombin pair, must also be studied.

OBJECTIVES

The objectives were (i) to quantitatively assess the subprocesses (prothrombin conversion and thrombin decay) and (ii) to understand the underlying mechanism by studying TG dynamics after prothrombin and antithrombin plasma level correction in PWC.

METHODS

We studied TG-TM in plasma samples of 36 healthy controls (HCs) and 41 PWC with prothrombin and antithrombin levels of <70% and after their correction. We initiated coagulation with an intermediate picomolar concentration of tissue factor. We determined the overall thrombin potential, prothrombin conversion, and thrombin decay.

RESULTS

TG-TM was increased in PWC compared with HC due to impaired thrombin inhibition. Indeed, thrombin decay capacity (min-1) decreased from 0.37 (0.35-0.40) in HC to 0.33 (0.30-0.37) in the Child-Turcotte-Pugh A (CTP-A; P = .09), 0.27 (0.26-0.30) in the CTP-B (P < .001), and 0.20 (0.19-0.20) in the CTP-C (P < .001) group. Concomitant correction of prothrombin and antithrombin increased endogenous thrombin potential with prothrombin conversion surpassing thrombin decay. By contrast, when we corrected only antithrombin, TG-TM was normalized and even consistent with a hypocoagulable phenotype in the CTP-C group.

CONCLUSION

Our results highlight that in PWC, hypercoagulability (evidenced in the presence of TM) is due to impaired thrombin decay, whereas low prothrombin levels do not translate into decreased prothrombin conversion, likely due to altered TM-activated protein C negative feedback.

Long-term risk of venous thromboembolism among patients with gastrointestinal non-neoplastic and neoplastic diseases: A prospective cohort study of 484 211 individuals

We conducted a prospective cohort study to examine the associations of 21 gastrointestinal diseases with the risk of incident venous thromboembolism (VTE). The study included 485 936 UK Biobank participants free of baseline VTE. The gastrointestinal diseases were defined by the International Classification of Disease (ICD)-9 and 10 codes with data from the nationwide inpatient data set, the primary care data set, and the cancer registries. Incident VTE cases were defined by ICD-9 and 10 codes with data from the nationwide inpatient data set. Cox proportional hazards regression was used to estimate the associations of baseline gastrointestinal diseases with incident VTE risk. During a median follow-up of 12.0 years, 13 646 incident VTE cases were diagnosed. Eleven gastrointestinal diseases (nine non-neoplastic and two neoplastic) were associated with an increased risk of incident VTE after Bonferroni corrections. The risk of VTE was >50% higher among patients with gallbladder and biliary tract cancer (hazard ratio [HR] 3.15, 95% confidence interval [CI] 95% CI 1.74-5.70), pancreatic cancer (HR 2.84, 95% CI 1.65-4.91), cirrhosis (HR 2.34, 95% CI 1.96-2.79), Crohn's disease (HR 1.61, 95% CI 1.33-1.95), or pancreatitis (HR 1.57, 95% CI 1.31-1.88) compared with individuals without each of these diseases. We observed multiplicative interactions of age, sex, and body mass index with some gastrointestinal diseases (p < .05). A more pronounced, increased risk of VTE was found among younger, female, or obese patients. The study suggests a 50% higher risk of developing VTE among patients with gallbladder and biliary tract cancer, pancreatic cancer, cirrhosis, Crohn's disease, or pancreatitis.

Reappraisal of the conventional hemostasis tests as predictors of perioperative bleeding in the era of rebalanced hemostasis in cirrhosis

New global laboratory procedures mimicking the in vivo hemostasis process led to the changing paradigm of cirrhosis from the prototype of hemorrhagic diseases to a condition in which hemostasis is normal but fragile, thus justifying the hemorrhagic/thrombotic tendencies that affect these patients. The new paradigm was instrumental to change the management of cirrhosis. For example, international guidelines warn against the entrenched practice of testing patients with conventional hemostasis tests and infusing those with abnormalities with fresh-frozen plasma, coagulation factor concentrates, or platelets, prior to surgery/invasive procedures. These recommendations are, however, largely disattended. The practice of testing patients with the prothrombin time or viscoelastometry and using arbitrary cutoffs to make decisions on perioperative prophylaxis is still common and probably driven by medicolegal issues. There is no doubt that prothrombin time and congeners tests are unable to predict bleeding in cirrhosis. However, it cannot be excluded that some tests may be useful in patients who are severely decompensated. Large prospective collaborative studies are warranted. Enrolled patients should be randomized to receive perioperative prophylaxis based on laboratory testing (eg, viscoelastometry, thrombomodulin-modified thrombin generation) or to usual care. However, for these trials to be useful, a third group of patients who do not receive prophylaxis should be included. In conclusion, until results from these studies are available, physicians attending cirrhosis should refrain from using laboratory tests with arbitrary cutoffs to make decision on perioperative prophylaxis. Decision should be made by considering the clinical history of individual patients and the risk of hemorrhage of specific procedures.

A combination of clot formation abnormalities in thromboelastometry has a high prognostic value in patients with acute-on-chronic liver failure

BACKGROUND

Global coagulation tests offer a better tool to assess procoagulant and anticoagulant pathways, fibrinolysis and clot firmness and evaluate more accurately coagulation defects compared to conventional coagulation tests. Their prognostic role in acute-on-chronic liver disease (ACLF) or acute decompensation (AD) has not been well established.

AIMS

To assess the properties and prognostic value of the coagulation profile measured by rotational thromboelastometry (ROTEM) in ACLF and AD.

METHODS

84 consecutive patients (35 ACLF and 49 AD) were prospectively studied. Twenty healthy persons matched for age and gender were used as controls. 'Hypocoagulable' or 'hypercoagulable' profiles on admission were assessed based on nine ROTEM parameters and mortality was recorded at 30 and 90 days.

RESULTS

Individual ROTEM parameters denoted significantly more hypocoagulability in patients compared to controls. 'Hypocoagulable' profile (defined as a composite of 4 or more ROTEM parameters outside the range) was associated with more severe liver disease assessed either as MELD or Child-Pugh scores ( P  < 0.001 for both) and higher 30-day mortality (Log-rank P  = 0.012). 'Hypocoagulable' profile (HR 3.160, 95% CI 1.003-9.957, P  = 0.049) and ACLF status (HR 23.786, 95% CI 3.115-181.614, P  = 0.002) were independent predictors of 30-day mortality, in multivariate model. A higher early mortality rate was shown in ACLF patients with 'hypocoagulable' phenotype compared to those without (Log-rank P  = 0.017). 'Hypocoagulable' profile was not associated with mortality in AD.

CONCLUSION

'Hypocoagulable' profile was associated with more advanced liver disease and higher short-term mortality in patients with ACLF.

Managing a Prospective Liver Transplant Recipient on the Waiting List

The management of a patient in the peri-transplantation period is highly challenging, and it is even more difficult while the patient is on the transplantation waitlist. Keeping the patient alive during this period involves managing the complications of liver disease and preventing the disease's progression. Based on the pre-transplantation etiology and type of liver failure, there is a difference in the management protocol. The current review is divided into different sections, which include: the management of underlying cirrhosis and complications of portal hypertension, treatment and identification of infections, portal vein thrombosis management, and particular emphasis on the management of patients of hepatocellular carcinoma and acute liver failure in the transplantation waitlist. The review highlights special concerns in the management of patients in the Asian subcontinent also. The review also addresses the issue of delisting from the transplant waitlist to see that futility does not overtake the utility of organs. The treatment modalities are primarily expressed in tabular format for quick reference. The following review integrates the vast issues in this period concisely so that the management during this crucial period is taken care of in the best possible way.

How to assess hemostasis in patients with severe liver disease

Patients with advanced liver diseases frequently acquire profound alterations in their hemostatic system. Simultaneous changes in procoagulant and anticoagulant systems result in a reset in the hemostatic balance with a relatively neutral net effect, although there are notable hypocoagulable and hypercoagulable features in the hemostatic system in patients with liver disease. Laboratory and clinical studies have demonstrated that patients have a relatively well-preserved hemostatic system even though routine diagnostic tests of hemostasis (prothrombin time, platelet count) suggest a bleeding tendency. Routine diagnostic tests of hemostasis are unsuitable to assess the hemostatic status of patients with liver disease, as these tests are insensitive for the concurrent prohemostatic and antihemostatic changes in these patients. These tests are, however, frequently requested in patients with liver disease, as they are well established indicators of severity of liver disease. This paper will discuss commonly used diagnostic and research-type hemostatic tests and will outline how test results should be interpreted in patients with liver disease.

Diagnostic Prediction of portal vein thrombosis in chronic cirrhosis patients using data-driven precision medicine model

BACKGROUND

Portal vein thrombosis (PVT) is a significant issue in cirrhotic patients, necessitating early detection. This study aims to develop a data-driven predictive model for PVT diagnosis in chronic hepatitis liver cirrhosis patients.

METHODS

We employed data from a total of 816 chronic cirrhosis patients with PVT, divided into the Lanzhou cohort (n = 468) for training and the Jilin cohort (n = 348) for validation. This dataset encompassed a wide range of variables, including general characteristics, blood parameters, ultrasonography findings and cirrhosis grading. To build our predictive model, we employed a sophisticated stacking approach, which included Support Vector Machine (SVM), Naïve Bayes and Quadratic Discriminant Analysis (QDA).

RESULTS

In the Lanzhou cohort, SVM and Naïve Bayes classifiers effectively classified PVT cases from non-PVT cases, among the top features of which seven were shared: Portal Velocity (PV), Prothrombin Time (PT), Portal Vein Diameter (PVD), Prothrombin Time Activity (PTA), Activated Partial Thromboplastin Time (APTT), age and Child-Pugh score (CPS). The QDA model, trained based on the seven shared features on the Lanzhou cohort and validated on the Jilin cohort, demonstrated significant differentiation between PVT and non-PVT cases (AUROC = 0.73 and AUROC = 0.86, respectively). Subsequently, comparative analysis showed that our QDA model outperformed several other machine learning methods.

CONCLUSION

Our study presents a comprehensive data-driven model for PVT diagnosis in cirrhotic patients, enhancing clinical decision-making. The SVM-Naïve Bayes-QDA model offers a precise approach to managing PVT in this population.

Anticoagulation in Patients with Liver Cirrhosis: Friend or Foe?

Concepts regarding the status of the coagulation process in cirrhosis are rapidly changing. Instead of a disease defined by excessive bleeding risk, recent studies have shown cirrhosis to be associated with a fragile state of rebalanced hemostasis, easily swayed in either direction, thrombosis, or bleeding. These findings, combined with the ever-growing population of patients with cirrhosis with an indication for anticoagulation (AC) and the emergence of the non-alcoholic fatty liver disease epidemic, have prompted a reexamination of the use of AC in patients with cirrhosis, either as a treatment for a concurrent thrombotic disorder or even as a possible therapeutic option that could influence the natural course of the disease and its complications. In recent years, a significant number of studies have been formulated to evaluate these possibilities. These studies evaluated, among others, the efficacy and safety of AC in thrombotic disorders or thrombotic complications of cirrhosis, its effect on survival, and the class of anticoagulants which is more suitable for patients with cirrhosis, depending on disease severity. This review examines recent studies investigating the use of AC in patients with cirrhosis and attempts to provide a simple guide for clinicians regarding the use of AC in patients with cirrhosis and its potential risks and benefits.

Viscoelastic Management of Coagulopathy during the Perioperative Period of Liver Transplantation

Viscoelastic testing (VET) in liver transplantation (LT) has been used since its origin, in combination with standard laboratory testing (SLT). There are only a few, small, randomized controlled trials that demonstrated a reduction in transfusion rates using VET to guide coagulation management. Retrospective analyses contrasting VET to SLT have demonstrated mixed results, with a recent concern for overtreatment and the increase in postoperative thrombotic events. An oversight of many studies evaluating VET in LT is a single protocol that does not address the different phases of surgery, in addition to pre- and postoperative management. Furthermore, the coagulation spectrum of patients entering and exiting the operating room is diverse, as these patients can have varying anatomic and physiologic risk factors for thrombosis. A single transfusion strategy for all is short sighted. VET in combination with SLT creates the opportunity for personalized resuscitation in surgery which can address the many challenges in LT where patients are at a paradoxical risk for both life-threatening bleeding and clotting. With emerging data on the role of rebalanced coagulation in cirrhosis and hypercoagulability following LT, there are numerous potential roles in VET management of LT that have been unaddressed.

Elevated levels of soluble glycoprotein V - The plasma marker of platelet activation by thrombin in patients with early stage primary biliary cholangitis (PBC)

PURPOSE

There is a growing body of evidence for a prothrombotic tendency in patients with primary biliary cholangitis (PBC). The aim of the study was to evaluate coagulation disorders in patients with early stage PBC compared to healthy controls and evaluation of their relationship with clinical data, with particular emphasis on minimal hepatic encephalopathy (MHE).

PATIENTS AND METHODS

Fifty-one participants (PBC group - 38 patients, all patients but one Child-Pugh A; control group - 13 healthy controls) were included in our prospective, single center study. We assessed the plasma levels of sGPV, plasma procoagulant phospholipids (PPL) and rotational thromboelastometry (ROTEM) profiles in all study participants. Porto-systemic encephalopathy syndrome test was used to assess MHE.

RESULTS

The sGPV levels were higher in the PBC group compared to the controls: 36.07 ​± ​11.32 ​ng/mL vs 27.04 ​± ​11.72 ​ng/mL, p ​= ​0.031. The PPL level was lower in the PBC group compared to controls resulting in increased clotting time in a factor Xa-based coagulation assay: 54.65 (47.83-58.83) sec. vs 45.90 (43.3-50.5) sec., p ​= ​0.0065. PPL levels were correlated with platelet count (rho ​= ​-0.46, p ​= ​0.001). ROTEM parameters did not differ significantly between groups. Coagulation parameters did not differ significantly between patients with and without MHE.

CONCLUSIONS

We have showed increased levels of sGPV - a plasma marker of platelet activation by thrombin in patients with early stage PBC compared to healthy controls. We found no relationship between the coagulation disorders and the occurrence of MHE. The PPL level was lower in the PBC group.

Haemostasis patterns in patients with acute-on-chronic liver failure and acute decompensation of cirrhosis including thromboelastometric tests with and without the addition of Protac: a pilot study

BACKGROUND

Thromboelastometry is considered the best method to assesses hemostasis in liver disease. Diagnostic performance could be improved by adding protein C activators such as thrombomodulin or Protac®. We assessed changes in ROTEM parameters after the addition of Protac® in patients with acute-on-chronic liver failure (ACLF), acute decompensation (AD), and healthy individuals (HI) to define different hemostasis patterns, considering standard and velocity ROTEM parameters, and assess whether Protac® can improve the definition of the pattern.

METHODS

Pre-test, we investigated whether diluted EXTEM reagent improved the effect of Protac® on the clotting time (CT)-ratio with and without Protac®. Ten ACLF and 20 AD patients and 21 HI were included in the main study.

RESULTS

Standard EXTEM was used in the main study. INTEM CFT, INTEM A5 (inverse), and INTEM TPI (inverse) were the parameters that best differentiated liver disease from HI (ROC AUC, 0.921, 0.906, and 0.928, respectively; all P-values < 0.001). Combining INTEM CFT with EXTEM LI60-ratio only slightly improved the diagnostic performance (ROC AUC, 0.948; P < 0.001). EXTEM LI60 and INTEM maxV-t were the parameters that best differentiated between ACLF and AD patients (ROC AUC, 0.743, P = 0.033; and 0.723, P = 0.050; respectively). Combining EXTEM LI60 + INTEM maxV-t moderately improved the diagnostic performance (ROC AUC, 0.81, P < 0.001).

CONCLUSIONS

ROTEM velocity, fibrinolysis parameters and the indices calculated improve the diagnosis in combination with standard parameters (e.g., CFT and A5). Ratios calculated with and without Protac® (e.g., EXTEM LI60-ratio) only slightly increased the diagnostic performance in discriminating hemostasis patterns.

Rational hemostatic management in cirrhosis: from old paradigms to new clinical challenges

INTRODUCTION

Patients with cirrhosis are at risk of both thrombotic and hemorrhagic events. Traditional hemostatic tests are inadequate to assess the complex and fragile balance of hemostasis in this setting, especially in advanced stages of disease such as decompensated cirrhosis or acute on chronic liver failure (ACLF). Furthermore, the indiscriminate use of pro-hemostatic agents for prophylaxis and treatment of bleeding episodes is still debated and often contraindicated. Alongside, splanchnic, and peripheral thrombotic events are frequent in this population and require management that involves a careful balance between risks and benefits of antithrombotic therapy.

AREAS COVERED

This review aims to address the state of the art on the clinical management of the hemostatic balance of cirrhosis in terms of established knowledge and future challenges.

EXPERT OPINION

The old paradigm of cirrhosis as a naturally anticoagulated condition has been challenged by more sophisticated global tests of hemostasis. Integrating this information in the clinical decision-making is still challenging for physicians and experts in hemostasis.

ADAMTS-13/von Willebrand factor ratio: A prognostic biomarker for portal vein thrombosis in compensated cirrhosis. A prospective observational study

BACKGROUND AND AIMS

In cirrhosis, decreased portal flow velocity, thrombophilia factors, and portal hypertension are considered risk factors for portal vein thrombosis (PVT). In cirrhosis, the transformation of the stellate cells causes a progressive decrease of ADAMTS-13, while VWF multimers secretion by endothelial cells is strongly enhanced. This imbalance leads to an accumulation of ultra-large VWF multimers that in sinusoidal circulation could favor PVT both in intra- and extra-hepatic branches, mostly in decompensated cirrhosis. This prospective study was aimed at identifying possible clinical, biochemical, and hemostatic factors predictive for non-tumoral PVT in a cohort of patients with compensated cirrhosis.

METHODS

Seventynine compensated cirrhosis patients were prospectively followed for 48 months, receiving a periodic Doppler-ultrasound liver examination associated with an extensive evaluation of clinical, biochemical, and hemostatic profile.

RESULTS

Five patients developed PVT (cumulative prevalence = 6.3%), occurring 4-36 months after enrollment. In logistic regression analysis, the ADAMTS-13/VWF:GpIbR ratio < 0.4 was the only independent variable significantly associated with PVT (OR 14.6, 95% C.I.:1.36-157.2, p = 0.027). A Cox-regression-analysis confirmed this finding (HR = 7.7, p = 0.027).

CONCLUSIONS

The ADAMTS-13/VWF ratio < 0.4 measured in compensated cirrhosis could be a reliable predictive biomarker for PVT development, paving the way to novel therapeutic strategies to prevent and treat PVT in this clinical setting.

Blood products and liver transplantation: A strategy to balance optimal preparation with effective blood stewardship

BACKGROUND

Unanticipated transfusion requirements during liver transplantation can delay lifesaving intraoperative resuscitation and strain blood bank resources. Risk-stratified preoperative blood preparation can mitigate these deleterious outcomes.

STUDY DESIGN AND METHODS

A two-tiered blood preparation protocol for liver transplantation was retrospectively evaluated. Eleven binary variables served as criteria for high-risk (HR) allocation. Primary outcomes included red blood cell (RBC), plasma (FFP), and platelet (Plt) utilization. Secondary outcomes included product under- and overpreparation. Contingency tables for transfusion requirements above the population means were generated using 15 clinical variables. Modified protocols were developed and retrospectively optimized using the study population.

RESULTS

Of 225 recipients, 102 received HR preoperative orders, which correlated to higher intraoperative transfusion requirements. However, univariate analysis identified only two statistical risk factors per product: Hgb ≤7.8 g/dl (p < .001) and MELD ≥38 (p = .035) for RBCs, Hgb ≤7.8 g/dl (p = .002) and acute alcoholic hepatitis (p = 0.015) for FFP, and Hgb ≤7.8 g/dl (p = .001) and normothermic liver preservation (p = .037) for Plts. Based on these findings, we developed modified protocols for individual products, which were evaluated retrospectively for their effectiveness at reducing under-preparatory events while limiting product overpreparation. Cohort statistics were used to define the preparation strategy for each protocol. Retrospective comparative analysis demonstrated the superiority of the modified protocols by improving the under-preparation rate from 24% to <10% for each product, which required a 1.56-fold and 1.44-fold increase in RBC and FFP overpreparation, respectively. Importantly, there was no difference in Plt overpreparation.

DISCUSSION

We report translatable data-driven blood bank preparation protocols for liver transplantation.

Coagulopathy and hemostasis management in patients undergoing liver transplantation: Defining a dynamic spectrum across phases of care

Patients with acute and chronic liver disease present with a wide range of disease states and severity that may require liver transplantation (LT). Physiologic alterations occur that are dynamic throughout all phases of perioperative care, creating complex management scenarios that necessitate multidisciplinary clinical care. Specifically, alterations in hemostasis in liver disease can be pronounced and evolve with disease progression over time. Recent studies and society guidance address this emerging paradigm and offer recommendations to assist with hemostatic management in patients with liver disease. However, patients undergoing LT are unique and diverse, often with unstable disease that requires specialized approaches. Our aim is to provide a focused review of hemostatic management of the LT patient, distinguish unique aspects of the three main phases of care (before LT, perioperative, and after LT), and identify knowledge gaps and critical areas of future research.

Blood loss during liver transplantation is a predictor of postoperative thrombosis

Liver transplantation (LT) is an effective way to cure end-stage liver diseases (ESLDs), which have generally been regarded as examples of acquired bleeding disorders. However, postoperative thrombosis after LT is recognised and remains a life-threatening complication. This study aimed to show that blood loss during LT is a predictor of postoperative thrombosis and to establish a predictive model. We analysed the medical records of all patients who underwent LT at the First Affiliated Hospital of Xi'an Jiaotong University from January 2017 to April 2019 to identify the risk factors for post-transplant thrombosis. The predictive nomogram was established based on independent predictors identified by logistic regression analysis. Blood loss during LT of ≥31.25 mL/kg can predict postoperative thrombosis, and the nomogram achieved an accurate prediction.

Mastering Core Recommendations during HEPAtology ROUNDS in Patients with Advanced Chronic Liver Disease

Efficient and thorough care of hospitalized patients with advanced chronic liver disease is of utter importance to improve outcomes and optimize quality of life. This requires understanding current evidence and best practices. To facilitate focus on up-to-date knowledge and a practical approach, we have created the HEPA-ROUNDS mnemonic while outlining a practical review of the literature with critical appraisal for the busy clinician. The HEPA-ROUNDS mnemonic provides a structured approach that incorporates critical concepts in terms of prevention, management, and prognostication of the most common complications frequently encountered in patients with advanced chronic liver disease. In addition, implementing the HEPA-ROUNDS mnemonic can facilitate education for trainees and staff caring for patients with advanced chronic liver disease.

Review article: thromboelastography in liver diseases

BACKGROUND

Patients with liver diseases have complicated haemostatic alternations, resulting in both bleeding and thromboembolic complications, which cannot be sufficiently evaluated by conventional coagulation tests (CCTs), such as platelet count or prothrombin time. Thromboelastography (TEG) is a whole blood viscoelastic test which globally reflects changes in the haemostatic system, and its utility in evaluating patients with liver disease is increasingly recognised.

AIMS

To review the current evidence and clinical significance of TEG in liver diseases.

METHODS

Literature regarding TEG and liver diseases was comprehensively searched.

RESULTS

TEG is associated closely with the severity and aetiology of liver disease, the course of infection and the risk of bleeding and death, but not the risk of portal venous system thrombosis. Additionally, TEG-guided transfusion protocols can significantly decrease the requirement for blood products compared to those guided by CCTs.

CONCLUSION

TEG can reflect the haemostatic status of liver diseases more comprehensively than CCTs. It has the potential to assess the severity of liver diseases, predict the risk of bleeding and death in patients with liver disease and guide blood product transfusion. Future studies should standardise the use of TEG for assessing disease severity and development of clinical events and guiding blood product transfusion in patients with liver diseases.

Management of Decompensated Cirrhosis in the Surgical ICU: an American Association for the Surgery of Trauma Critical Care Committee Clinical Consensus Document

Management of decompensated cirrhosis (DC) can be challenging for the surgical intensivist. Management of DC is often complicated by ascites, coagulopathy, hepatic encephalopathy, gastrointestinal bleeding, hepatorenal syndrome, and difficulty assessing volume status. This Clinical Consensus Document created by the American Association for the Surgery of Trauma Critical Care Committee reviews practical clinical questions about the critical care management of patients with DC to facilitate best practices by the bedside provider.

Portal Vein Thrombosis in Cirrhosis

Patients with cirrhosis of the liver are at high risk of developing portal vein thrombosis (PVT), which has a complex, multifactorial cause. The condition may present with a myriad of symptoms and can occasionally cause severe complications. Contrast-enhanced computed tomography (CT) is the gold standard for the diagnosis of PVT. There are uncertainties regarding the effect on PVT and its treatment outcome in patients with cirrhosis. The main challenge for managing PVT in cirrhosis is analyzing the risk of hemorrhage compared to the risk of thrombus extension leading to complications. All current knowledge regarding non-tumor PVT in cirrhosis, including epidemiology, risk factors, classification, clinical presentation, diagnosis, impact on natural history, and treatment, is discussed in the present article.

EASL Clinical Practice Guidelines on prevention and management of bleeding and thrombosis in patients with cirrhosis

The prevention and management of bleeding and thrombosis in patients with cirrhosis poses several difficult clinical questions. These Clinical Practice Guidelines have been developed to provide practical guidance on debated topics, including current views on haemostasis in liver disease, controversy regarding the need to correct thrombocytopenia and abnormalities in the coagulation system in patients undergoing invasive procedures, and the need for thromboprophylaxis in hospitalised patients with haemostatic abnormalities. Multiple recommendations in this document are based on interventions that the panel feels are not useful, even though widely applied in clinical practice.

Direct oral anticoagulant administration in cirrhotic patients with portal vein thrombosis: What is the evidence?

In recent years, the traditional concept that cirrhosis-related coagulopathy is an acquired bleeding disorder has evolved. Currently, it is known that in cirrhotic patients, the hemostatic system is rebalanced, which involves coagulation factors, fibrinolysis and platelets. These alterations disrupt homeostasis, skewing it toward a procoagulant state, which can lead to thromboembolic manifestations, especially when hemodynamic and endothelial factors co-occur, such as in the portal vein system in cirrhosis. Portal vein thrombosis is a common complication of advanced liver cirrhosis that negatively affects the course of liver disease, prognosis of cirrhotic patients and success of liver transplantation. It is still debated whether portal vein thrombosis is the cause or the consequence of worsening liver function. Anticoagulant therapy is the mainstay treatment for acute symptomatic portal vein thrombosis. In chronic portal vein thrombosis, the role of anticoagulant therapy is still unclear. Traditional anticoagulants, vitamin K antagonists and low-molecular-weight heparin are standard-of-care treatments for portal vein thrombosis. In the last ten years, direct oral anticoagulants have been approved for the prophylaxis and treatment of many thromboembolic-related diseases, but evidence on their use in cirrhotic patients is very limited. The aim of this review was to summarize the evidence about the safety and effectiveness of direct oral anticoagulants for treating portal vein thrombosis in cirrhotic patients.

Predictors of Deep Venous Thrombosis in Hospitalized Patients With Liver Cirrhosis in the US

Background

Patients with liver cirrhosis were previously considered as anticoagulated; thus, their risk of developing venous thromboembolism (VTE) is lower. Recently, several studies showed contradicting results regarding deep venous thrombosis (DVT) occurrence in cirrhotic patients. The aim of this study is to evaluate the prevalence and risk associated with developing DVT in hospitalized cirrhotic patients in a large US population.

Methods

We queried the commercial database Explorys (IMB Inc., Armonk, New York), an aggregate of electronic health record data from 26 US healthcare systems. After excluding patients under 20 years old, a cohort of patients with a Systematized Nomenclature of Medicine - Clinical Terms of "cirrhosis of the liver" and "inpatient care" between 2015-2019 were identified, and prevalence of DVT was calculated in the exposure and the control groups. Statistical analysis for a multivariable model was performed. Factors adjusted for include gender, race, obesity, hypoalbuminemia, diabetes mellitus, viral hepatitis, and liver malignancy.

Results

Among 9,990,290 patients who were hospitalized between 2015 and 2019, 157,400 patients had a diagnosis of liver cirrhosis. The prevalence of DVT in hospitalized patients with liver cirrhosis was 3.29% compared to 3.18% in non-cirrhotic patients. Using the multivariate analysis model, DVT was inversely associated with cirrhosis in hospitalized patients [OR: 0.921; p<0.0001] compared to patients without liver cirrhosis. Predictors of developing DVT among patients with cirrhosis were non-Caucasian race, obesity (BMI>30), liver malignancy, hypoalbuminemia, and diabetes mellitus. Cirrhotic patients due to viral hepatitis were less likely to develop DVT [OR: 0.775; p<0.001] compared to non-cirrhotic patients.

Conclusion

In this database, although the prevalence of DVT in cirrhotic hospitalized patients was slightly higher than in non-cirrhotic patients (3.29% vs. 3.18%, respectively), cirrhosis as an independent factor was associated with less risk of DVT during hospitalization. This poses a question regarding DVT prophylaxis necessity in this group of patients. Further studies are needed to clarify the benefit and risks of DVT prophylaxis in cirrhotic patients. 

Association of ABO Blood Type with Bleeding Severity in Patients with Acute Gastroesophageal Variceal Bleeding

Background and Objectives: ABO blood types have been implicated as potential risk factors for various hemorrhagic diseases. No study has investigated the association between gastroesophageal variceal bleeding and ABO blood types. We aimed to evaluate the impact of ABO blood types on mortality and bleeding risk in acute gastroesophageal variceal bleeding. Materials and Methods: This is a retrospective observational study. Patients presenting with acute gastroesophageal varices bleeding diagnosed by endoscopy were enrolled, and were divided by blood type into a type O group and non-type O group. The outcomes were death within 30 days and the proportion of further bleeding. We used generalized linear mixed-effects models to analyze the outcomes. Results: A total of 327 patients and 648 records of emergency room visits were included. The 30-day mortality was 14.8% (21 of 142 patients) in the type O group, and 16.2% (30 of 185 patients) in the non-type O group (p = 0.532). Further bleeding within 30 days occurred in 34 cases (12.6%) in the type O group, and in 26 cases (6.9%) in the non-type O group (p = 0.539). Conclusions: There was no significant difference in blood transfusion volume in 24 h, recurrent bleeding rates, or mortality between patients with blood type O and those with non-type O.

Safety and efficacy of dual antiplatelet therapy after percutaneous coronary interventions in patients with end-stage liver disease

The prevalence of coronary artery disease (CAD) increases in patients with end-stage liver disease, with part of them receiving the percutaneous coronary intervention (PCI) as a treatment option. Dual antiplatelet therapy (DAPT), a standard of care after PCI, could result in catastrophic consequences in this population. Before PCI and the start of DAPT, it is recommended to assess patient bleeding risk. Based on novel findings, liver cirrhosis does not necessarily lead to a significant increase in bleeding complications. Furthermore, conventional methods, such as the international normalized ratio, might not be appropriate in assessing individual bleeding risk. The highest bleeding risk among cirrhotic patients has a subgroup with severe thrombocytopenia (< 50 × 109/L) and elevated portal pressure. Therefore, every effort should be made to maintain thrombocyte count above > 50 × 109/L and prevent variceal bleeding. There is no solid evidence for DAPT in patients with cirrhosis. However, randomized trials investigating short (one month) DAPT duration after PCI with new drug-eluting stents (DES) in a high bleeding risk patient population can be implemented in patients with cirrhosis. Based on retrospective studies (with older stents and protocols), PCI and DAPT appear to be safe but with a higher risk of bleeding complications with longer DAPT usage. Finally, novel methods in assessing CAD severity should be performed to avoid unnecessary PCI and potential risks associated with DAPT. When indicated, PCI should be performed over radial artery using contemporary DES. Complementary medical therapy, such as proton pump inhibitors and beta-blockers, should be prescribed for lower bleeding risk patients. Novel approaches, such as thromboelastography and "preventive" upper endoscopies in PCI circumstances, warn clinical confirmation.

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.

Coagulopathy is not predictive of bleeding in patients with acute decompensation of cirrhosis and acute-on-chronic liver failure

BACKGROUND & AIMS

Understanding factors responsible for the increased bleeding tendency in acute-on-chronic liver failure (ACLF) would improve the management of these complications. We investigated coagulation alterations in ACLF and assessed whether they were predictive of bleeding.

METHODS

Cirrhosis patients with ACLF (cases) and acute decompensation (AD, controls) were prospectively recruited and underwent an extensive haemostatic assessment including standard tests, pro and anticoagulant factors, thrombomodulin-modified thrombin generation (TG) and thromboelastometry (ROTEM® ). In study part 1 (case-control), we compared coagulation in ACLF vs AD. In study part 2 (prospective), all patients were followed for bleeding, and predictors of outcome were assessed.

RESULTS

Ninety-one patients were included (51 with ACLF, 40 with AD). Infections and ascites/renal dysfunction were the most common precipitating and decompensating events. Platelet count was lower while INR and activated partial thrombin time were longer in ACLF cohort vs AD. Regarding clotting factors, fibrinogen and factor VIII were comparable between groups while protein C and antithrombin were significantly reduced in ACLF. Endogenous thrombin potential by TG was comparable between groups. Clotting formation time and clot stability by ROTEM® were significantly lower in ACLF, indicative of a more hypocoagulable state. No haemostasis alteration could discriminate between patients who had bleeding complications during hospitalization and those who did not.

CONCLUSION

We found coagulation changes in ACLF to largely overlap with that of AD and evidence of preserved coagulation capacity in both groups. ROTEM alterations were indicative of a more pronounced hypocoagulable state in ACLF; however, no correlation was found between such alterations and bleeding.

Rates of Bleeding and Discontinuation of Direct Oral Anticoagulants in Patients With Decompensated Cirrhosis

BACKGROUND & AIMS

Studies of the effects of direct oral anticoagulants (DOACs) in patients with cirrhosis have been limited by their small sample size, inclusion of patients with well-compensated cirrhosis, short follow-up times, inadequate validation of cirrhosis diagnoses, and non-standard definitions of bleeding. We aimed to systematically determine the characteristics, indications, and outcomes of patients with cirrhosis of all severity classes who received DOACs.

METHODS

We performed a retrospective study of 138 patients with confirmed cirrhosis (93 with Child-Turcotte-Pugh scores of B or C) at a single center who started DOAC therapy (58,984 person-days; median, 181 days per patient) from September 2011 through April 2019. We collected data on clinical characteristics, indications for DOAC use, and outcomes. Standardized and validated definitions for bleeding complications were used.

RESULTS

Twenty-nine patients (21%) stopped therapy due to a diagnosis of or perceived bleeding. The most common bleeding events were non-variceal upper and lower intestinal bleeding. No pretreatment laboratory parameters were associated with bleeding while patients received treatment, including platelet count (P = .50), international normalized ratio (P = .34), creatinine (P = .27), and model for end-stage liver disease score (P = .22). Frequency of bleeding events related to DOAC did not differ significantly among patients of different Child-Turcotte-Pugh classes (P = .81), DOAC indications (P = .60), or DOAC dosages (P = .10). Higher proportions of patients with hepatocellular carcinoma (P = .01) had major bleeding while receiving.

CONCLUSIONS

Patients with decompensated cirrhosis have significant bleeding and rates of discontinuation of DOACs when they take them long term. Pretreatment laboratory parameters, DOAC dose, and Child-Turcotte-Pugh class were not associated with bleeding; hepatocellular carcinoma was associated with major bleeding.

Treatment of direct oral anticoagulants in patients with liver cirrhosis and portal vein thrombosis

Although patients with cirrhosis are known to be in a state of “rebalance” in that pro- and anticoagulant factors increase the risk for both bleeding and thrombosis, the prevalence of portal vein thrombosis (PVT) in patients with cirrhosis can be up to 26%. Therefore, physicians should consider anticoagulation for the prevention and management of PVT in patients with cirrhosis who are at high risk of PVT. Vitamin K antagonist or low molecular weight heparin is suggested as the standard treatment for PVT in cirrhosis. With the advent of new direct-acting oral anticoagulants (DOACs), there is a paradigm shift of switching to DOACs for the treatment of PVT in patients with cirrhosis. However, the safety and efficacy of DOACs in the treatment of PVT was not well-known in patients with cirrhosis. Therefore, this review focused on the current knowledge about the efficacy, safety concerns, and hepatic metabolism of DOACs in patients with cirrhosis and PVT.

The concept of rebalanced hemostasis in patients with liver disease: Communication from the ISTH SSC working group on hemostatic management of patients with liver disease

Patients with liver diseases acquire complex alterations in their hemostatic system that may lead to abnormalities in routine diagnostic test of hemostasis. Thrombocytopenia, prolongations in the prothrombin time and activated partial thromboplastin time, and decreased plasma fibrinogen are common in patients with advanced liver disease. Historically, liver diseases therefore have been classified as an acquired bleeding disorder. Laboratory and clinical observations have demonstrated that although routine diagnostic tests of hemostasis suggest a hypocoagulable state, patients with liver disease also tend to develop thrombotic events. Overall, patients have commensurate changes in both pro- and antihemostatic pathways. This new hemostatic balance, however, appears much more fragile than the hemostatic balance in individuals with normal liver function, and patients with liver disease can readily experience both hemostasis-related bleeding and thrombotic events. These insights into the hemostatic balance in patients with liver disease have led to revised recommendations for clinical management of hemostasis. In 2020, an SSC working group within the ISTH has been founded with the aim to disseminate new concepts on prevention and treatment of bleeding and thrombosis in patients with liver disease. The current document will outline the hemostatic changes in patients with liver disease, the limitations of routine diagnostic tests of hemostasis, and the concept of rebalanced hemostasis.

Exploring the Complex Role of Coagulation Factor VIII in Chronic Liver Disease

Chronic liver disease is one of the leading causes of death in the United States. Coagulopathy is often a sequela of chronic liver disease, however, the role and regulation of coagulation components in chronic liver injury remain poorly understood. Clinical and experimental evidence indicate that misexpression of the procoagulant factor VIII (FVIII) is associated with chronic liver disease. Nevertheless, the molecular mechanism of FVIII-induced chronic liver injury progression remains unknown. This review provides evidence supporting a pathologic role for FVIII in the development of chronic liver disease using both experimental and clinical models.

Procoagulant activity in high grade serous ovarian cancer patients following neoadjuvant chemotherapy-The role of the activated protein C pathway

INTRODUCTION

Ovarian cancer patients are at high risk of thrombosis particularly during chemotherapy treatment however the mechanism is not understood. The aim of this study is to investigate the role of the activated protein C (aPC) pathway in the procoagulant activity observed in ovarian cancer patients undergoing neoadjuvant chemotherapy.

PATIENTS AND METHODS

Thrombin generation was determined before and after addition of thrombomodulin (TM) in high grade serous ovarian cancer (HGSOC) patients treated with neoadjuvant chemotherapy (n = 29) compared with HGSOC patients who were chemo naïve (n = 23) and patients with benign tumours (n = 29). Plasma expression of proteins from the aPC pathway was analysed. mRNA expression was determined in endothelial (EA.hy926) and ovarian (OAW42) cell lines following addition of carboplatin and paclitaxel.

RESULTS

Lower levels of ETP (p < 0.007; p < 0.003) and peak thrombin (p < 0.0008; p < 0.0018) were found in the neoadjuvant group compared with both chemo naïve and benign groups. Following addition of TM, ETP (p < 0.0005) and peak thrombin (p < 0.0049) were higher in the neoadjuvant group compared with the benign controls indicating an increase in aPC resistance. Increased TM and lower levels of protein S were found in the neoadjuvant group compared with benign controls (p < 0.05; p < 0.003). Factor V levels were increased in the neoadjuvant group compared with the chemo naïve group (p < 0.05). Carboplatin and paclitaxel altered the expression of EPCR and thrombomodulin in OAW42 cells with a modest effect on EA.hy926 cells.

CONCLUSION

Chemotherapy induced procoagulant activity in HGSOC is associated with an alteration in expression of key members of the aPC pathway. This acquired aPC resistance may explain the procoagulant phenotype associated with ovarian cancer patients undergoing chemotherapy.

ST Genesia reference values of 117 healthy donors measured with STG-BleedScreen, STG-DrugScreen and STG-ThromboScreen reagents

INTRODUCTION

The ST Genesia is a benchtop, fully automated thrombin generation (TG) device. It is completely standardized and ensures a uniform heat distribution throughout the measurement. We aimed to determine reference values and to compare TG in men and women with and without the use of oral contraceptives (OCs).

MATERIALS AND METHODS

Plasma from 117 healthy donors was measured on the ST Genesia with the available reagent kits: STG-BleedScreen, STG-DrugScreen, and STG-ThromboScreen. All kits include at least two quality controls and a reference plasma to normalize data. STG-ThromboScreen has a second trigger containing thrombomodulin (TM) to include the effect on the protein C pathway. Means were compared with one-way analysis of variance and reference ranges were established with 2.5th to 97.5th percentiles on absolute TG parameters.

RESULTS

Mean age of the donors was 35 years (SD ± 12); 49.6% were men, 37.6% women without OCs, and 12.8% women with OCs. Men and women without OCs had, respectively, a mean peak height of 167 nM and 164 nM with STG-BleedScreen, 335 nM and 351 nM with STG-DrugScreen, and 192 nM and 198 nM with STG-ThromboScreen. Women taking OCs had a mean peak height of 263 nM, 473 nM, and 312nM, respectively (P < .05 compared to men/women without OCs). TM decreased endogenous thrombin potential by 54% in men, 47% in women without OCs, and only 25% in women with OCs (P < .05 compared to men/women without OCs).

CONCLUSIONS

TG in men and women without OCs was similar; however, women taking OCs had significantly higher TG values, and the effect of TM was also less pronounced in these women.

Anticoagulation in patients with advanced liver disease: an open issue

Liver disease has been long considered as a risk factor for bleeding for the presence of prolongation of global tests of clotting activation and low platelet count. For this reason, the use of anticoagulants in patients with liver disease and an indication to anticoagulation, such as atrial fibrillation of venous thrombosis, has been poorly considered. Furthermore, recent studies underscored the fact that patients with chronic liver disease may experience thrombosis in portal as well as systemic circulation and treatment with anticoagulants should be considered. The introduction of direct oral anticoagulants has increased therapeutic options for thromboprophylaxis; however, evidence on their safety and efficacy in specific populations, such as patients with liver disease, is still scarce and needs further investigation. Thus, atrial fibrillation patients with coexistent liver disease have been excluded from clinical trials with direct oral anticoagulants. Here, we provide an overview on mechanisms of thrombosis in patients with advanced chronic liver disease and a summary of evidence on the use of oral anticoagulants in patients with liver disease and portal vein thrombosis or atrial fibrillation.

The Clotting Trigger Is an Important Determinant for the Coagulation Pathway In Vivo or In Vitro-Inference from Data Review

Blood coagulation comprises a series of enzymatic reactions leading to thrombin generation and fibrin formation. This process is commonly illustrated in a waterfall-like manner, referred to as the coagulation cascade. In vivo, this "cascade" is initiated through the tissue factor (TF) pathway, once subendothelial TF is exposed and bound to coagulation factor VII (FVII) in blood. In vitro, a diminutive concentration of recombinant TF (rTF) is used as a clotting trigger in various global hemostasis assays such as the calibrated automated thrombogram, methods that assess fibrin turbidity and fibrin viscoelasticity tests such as rotational thromboelastometry. These assays aim to mimic in vivo global coagulation, and are useful in assessing hyper-/hypocoagulable disorders or monitoring therapies with hemostatic agents. An excess of rTF, a sufficient amount of negatively charged surfaces, various concentrations of exogenous thrombin, recombinant activated FVII, or recombinant activated FIXa are also used to initiate activation of specific sub-processes of the coagulation cascade in vitro. These approaches offer important information on certain specific coagulation pathways, while alterations in pro-/anticoagulants not participating in these pathways remain undetectable by these methods. Reviewing available data, we sought to enhance our knowledge of how choice of clotting trigger affects the outcome of hemostasis assays, and address the call for further investigations on this topic.

Nonalcoholic Fatty Liver Disease-Evidence for a Thrombophilic State?

Nonalcoholic fatty liver disease is the leading cause of liver disease worldwide. It has expansive extrahepatic morbidity and mortality including increased rates of both cardiovascular disease and venous thromboembolism. Derangements in primary, secondary and tertiary hemostasis are found in nonalcoholic fatty liver disease independent of those ascribed to end-stage liver disease. The abnormalities across all stages of hemostasis explain the increased rates of clinically relevant thrombotic events, including pulmonary embolism, deep vein thrombosis and portal vein thrombosis, which on an epidemiologic basis appears to be independent of obesity and other traditional venous thromboembolic risk factors. However, given the complex interaction between obesity, body composition and nonalcoholic fatty liver disease and the potential for exercise to benefit all three, more research is needed to further define the role of each in contributing to the prohemostatic state of nonalcoholic fatty liver disease in order to improve patient oriented outcomes.

Hypercoagulability (thrombin generation) in patients with cirrhosis is detected with ST-Genesia

BACKGROUND

Thrombin generation assays (TGAs) performed with calibrated automated thrombography (CAT) in the presence of thrombomodulin (TM) indicate plasma hypercoagulability in cirrhosis.

OBJECTIVE

To evaluate, in the presence of TM, the new ST-Genesia automated device developed for improving TGA vs the previously used CAT method, with plasma samples of patients with cirrhosis.

PATIENTS/METHODS

Platelet-poor plasma samples were prepared from citrated blood samples of 52 healthy controls and 85 patients with cirrhosis (severity evaluated using the Child-Pugh score [CP]). TGAs were performed using CAT with PPP-Reagent and ST-Genesia with the STG-ThromboScreen reagent, in the presence of TM. Endogenous thrombin potential (ETP) was chosen as the main parameter.

RESULTS

Whatever the method, ETP values were higher in patients than in healthy controls. All patients identified as hypercoagulable with ST-Genesia and STG-ThromboScreen were found hypercoagulable with CAT and PPP-Reagent. Conversely, eight and ten patients in the CP-A and CP-B classes respectively were identified as hypercoagulable only with CAT. The use of ST-Genesia with the STG-ThromboScreen reagent with TM led to a bias, with higher ETP values for healthy controls and lower for patients compared with CAT. Crossover analysis (CAT with the STG-ThromboScreen reagent) evidenced a substantial effect of the STG-ThromboScreen reagent; the analyzer (including calibration and data analysis) plays a lesser role.

CONCLUSION

ST-Genesia evidences hypercoagulability in patients with cirrhosis when TG is studied in the presence of TM, but the results are not interchangeable with those obtained with CAT.

Thrombin Generation and Cirrhosis: State of the Art and Perspectives

Epidemiological and laboratory studies performed in the last decades have changed our understanding of coagulopathy in cirrhosis, from a condition at increased risk of hemorrhagic events to one at higher thrombotic risk. However, it is not clear whether the decrease in factors that promote (except factor [F] VIII) versus inhibit coagulation in patients with cirrhosis results in a rebalanced state or in a hypercoagulable phenotype. This issue can be partially addressed using thrombin generation assays (TGA), which unlike routine clotting tests (prothrombin time or activated partial thromboplastin time) are sensitive to both procoagulant factors and coagulation inhibitors. However, many preanalytical issues and variable analytical methodologies used in TGAs complicate data analysis and interlaboratory comparisons. The introduction of TGAs in which activators of the protein C pathway (particularly soluble forms of thrombomodulin [TM]) are added has allowed detection of a reduced anticoagulant effect of TM or even a hypercoagulable phenotype as judged by endogenous thrombin potential. However, inter- and intra-assay variability may be greater with this TGA variant compared with "standard" TGAs. TGAs also allowed identifying main determinants of the hypercoagulability phenotype in the presence of TM: acquired antithrombin and protein C deficiencies, and elevated FVIII levels. The aim of this narrative review is to summarize the preanalytical and methodological variables of TGAs and also the findings of the main studies that have evaluated TGAs in patients with cirrhosis. The review also provides some propositions for future studies and outlines some perspectives on the potential implementation of this promising tool in clinical practice for the study of coagulation in patients with cirrhosis.

Deciphering the coagulation profile through the dynamics of thrombin activity

Thrombosis has proven to be extremely difficult to predict. Measuring the generation of thrombin is a very sensitive method to detect changes in the hemostatic system. We developed a method based on the generation of thrombin to further fingerprint hemostasis, which we have named thrombin dynamics. Via this method we are able to exactly measure the prothrombin conversion and thrombin inactivation, and any change in the coagulation cascade will be reflected in these two processes. In the current study we analyzed the importance of the members of the prothrombin complex on the dynamics of thrombin activation and inactivation. We show that prothrombin conversion is predominantly influenced by factor X and antithrombin, which will provide essential insights in complex thrombosis-related diseases, such as liver cirrhosis and kidney failure.