Role, Laboratory Assessment and Clinical Relevance of Fibrin, Factor XIII and Endogenous Fibrinolysis in Arterial and Venous Thrombosis

"Synergistic anticoagulant and endothelial regeneration strategy" based on mussel-inspired phospholipid copolymer coating and bioactive zeolitic imidazolate frameworks-90 to maintain the patency of CoCr stent

Given the risks of poor patient compliance and bleeding associated with current dual antiplatelet therapies, it is urgent to develop the next generation of cardiovascular stents with anticoagulation and rapid endothelialization capabilities. Inspired by the prominent bioactivity and bioavailability of zeolitic imidazolate framework-90 (ZIF-90) in driving endothelial cell (EC) morphogenesis, this research proposes a "synergistic anticoagulant and endothelial regeneration strategy" depending on mussel-inspired phospholipid copolymer (MIPC) and ZIF-90. Depending on the copolymerization of the catechol with dopamine (Dopa) monomers, Dopa/MIPC coating was immobilized on the surface of CoCr via a one-pot process for resisting the initial thrombosis induced by platelets and fibrinogen. Meanwhile, ZIF-90 was loaded on the coating via coordination effect, aiming to accelerate the proliferation and migration of ECs. Compared with CoCr, the well-designed CoCr-Dopa/MIPC@ZIF-90 not only reduced fibrinogen adhesion by approximately 40 % and platelet adhesion by almost 55 %, but also promoted the proliferation and migration of ECs significantly in vitro. Furthermore, the blood flow velocity of CoCr-Dopa/MIPC@ZIF-90 stent was similar to natural aorta and ECs coverage on it was greatly strengthened after 30 days in a rat aorta vascular stent implantation model. Collectively, CoCr-Dopa/MIPC@ZIF-90 exhibited obvious superiority in reducing the formation of thrombus and promoting endothelial regeneration, which might meet the high requirement for the next generation of vascular stent.

Research into New Molecular Mechanisms in Thrombotic Diseases Paves the Way for Innovative Therapeutic Approaches

Thrombosis is a multifaceted process involving various molecular components, including the coagulation cascade, platelet activation, platelet-endothelial interaction, anticoagulant signaling pathways, inflammatory mediators, genetic factors and the involvement of various cells such as endothelial cells, platelets and leukocytes. A comprehensive understanding of the molecular signaling pathways and cell interactions that play a role in thrombosis is essential for the development of precise therapeutic strategies for the treatment and prevention of thrombotic diseases. Ongoing research in this field is constantly uncovering new molecular players and pathways that offer opportunities for more precise interventions in the clinical setting. These molecular insights into thrombosis form the basis for the development of targeted therapeutic approaches for the treatment and prevention of thrombotic disease. The aim of this review is to provide an overview of the pathogenesis of thrombosis and to explore new therapeutic options.

Comparative Efficacy and Safety of Measures for the Treatment of Adults with Isolated Calf Muscular Vein Thrombosis: A Systematic Review and Network Meta-analysis

BACKGROUND

Isolated calf muscular vein thrombosis (ICMVT) can result in pulmonary embolism, but the treatment of ICMVT remains controversial. Therefore, the purpose of the present study was to investigate the optimal treatment for the ICMVT by comparing the efficacy and safety of different treatments.

METHODS

A network meta-analysis was conducted to search for studies published from database inception to April 30, 2022, that compared the outcomes of 2 or more treatments for ICMVT. The primary outcomes were efficacy (resolution rate) and safety (adverse reactions). Data were extracted following predefined hierarchy and the Cochrane Collaboration risk of bias tool was used to evaluate the methodological quality of the included studies. We estimated summary odds ratios with 95% credibility intervals using Bayesian network meta-analysis with random effects.

RESULTS

A total of 16 studies were enrolled in the study. In terms of efficacy and safety, urokinase thrombolysis combined with low-molecular-weight heparin (LMWH) was most effective but had the lowest safety, while physical therapy was safest but had the lowest efficacy. More important, direct oral factor Xa inhibitors were most likely to be second most effective and safe compared with other treatments. For the duration of treatment, anticoagulant therapy for at least 3 months could effectively increase the resolution rate of ICMVT.

CONCLUSIONS

Considering both efficacy and safety, taking direct oral factor Xa inhibitors for at least 3 months was the optimal treatment compared to LMWH, urokinase thrombolysis combined LMWH, physical therapy and warfarin for patients with ICMVT.

The Intricate Role of Non-Coding RNAs in Sepsis-Associated Disseminated Intravascular Coagulation

Disseminated Intravascular Coagulation (DIC) is a type of tissue and organ dysregulation in sepsis, due mainly to the effect of the inflammation on the coagulation system. Unfortunately, the underlying molecular mechanisms that lead to this disorder are not fully understood. Moreover, current biomarkers for DIC, including biological and clinical parameters, generally provide a poor diagnosis and prognosis. In recent years, non-coding RNAs have been studied as promising and robust biomarkers for a variety of diseases. Thus, their potential in the diagnosis and prognosis of DIC should be further studied. Specifically, the relationship between the coagulation cascade and non-coding RNAs should be established. In this review, microRNAs, long non-coding RNAs, and circular RNAs are studied in relation to DIC. Specifically, the axis between these non-coding RNAs and the corresponding affected pathway has been identified, including inflammation, alteration of the coagulation cascade, and endothelial damage. The main affected pathway identified is PI3K/AKT/mTOR axis, where several ncRNAs participate in its regulation, including miR-122-5p which is sponged by circ_0005963, ciRS-122, and circPTN, and miR-19a-3p which is modulated by circ_0000096 and circ_0063425. Additionally, both miR-223 and miR-24 were found to affect the PI3K/AKT pathway and were regulated by lncGAS5 and lncKCNQ1OT1, respectively. Thus, this work provides a useful pipeline of inter-connected ncRNAs that future research on their impact on DIC can further explore.

Modified Rotational Thromboelastometry Protocol Using Tissue Plasminogen Activator for Detection of Hypofibrinolysis and Hyperfibrinolysis

Viscoelastic testing includes thromboelastography (TEG^®) and thromboelastometry (ROTEM^®) and is widely used in bleeding patients to detect hypocoagulability and guide transfusion therapy. However, the ability of standard viscoelastic tests to assess fibrinolytic capacity is limited. We here describe a modified ROTEM^® protocol with addition of tissue plasminogen activator that can be used to identify hypofibrinolysis or hyperfibrinolysis.

Combination of D-dimer and Albumin in the Prediction of Deep Vein Thrombosis in Patients with Spontaneous Intracerebral Hemorrhage

BACKGROUND AND PURPOSE

Deep venous thrombosis (DVT) makes spontaneous intracerebral hemorrhage (ICH) treatment more challenging. We aimed to determine the predictive ability of D-dimer combination with albumin for DVT in spontaneous ICH.

METHODS

Spontaneous ICH patients were retrospectively included. Univariate and multivariate logistic regression analyses were performed. The restricted cubic spline (RCS) curve was adopted. Multivariate logistic regression analysis was further conducted to assess the predictive powers of D-dimer and albumin in different models. Besides, the incremental predictive ability of D-dimer combination with albumin was evaluated with areas under the curve (AUC), net reclassification improvement (NRI), and integrated discrimination index (IDI).

RESULTS

D-dimer was significantly higher, while albumin was considerably lower in the DVT group than in the non-DVT group [D-dimer, 0.47 (0.29, 1.08) versus 0.98 (0.48, 2.49), P < .001; albumin, 39.45 ± 7.05 versus 36.93 ± 4.77, P < .001). The multivariate logistic regression analysis showed that higher D-dimer and lower albumin were independently related to DVT after controlling confounders (D-dimer, OR = 1.061, 95% CI = 1.012-1.112, P = .013; albumin, OR = 0.934, 95% CI = 0.895-0.973, P = .001). The best cut-off value of the D-dimer was 0.40, and the albumin was 37.15. Besides, D-dimer and albumin had good predictive abilities in different models. The AUC, NRI, and IDI revealed that models that included the D-dimer combination with albumin had better predictability than those without.

CONCLUSIONS

D-dimer combination with albumin has a good predictability of DVT in spontaneous ICH.

The Role of the Coagulation System in Peripheral Arterial Disease: Interactions with the Arterial Wall and Its Vascular Microenvironment and Implications for Rational Therapies

Peripheral artery disease (PAD) is a clinical manifestation of atherosclerotic disease with a large-scale impact on the economy and global health. Despite the role played by platelets in the process of atherogenesis being well recognized, evidence has been increasing on the contribution of the coagulation system to the atherosclerosis formation and PAD development, with important repercussions for the therapeutic approach. Histopathological analysis and some clinical studies conducted on atherosclerotic plaques testify to the existence of different types of plaques. Likely, the role of coagulation in each specific type of plaque can be an important determinant in the histopathological composition of atherosclerosis and in its future stability. In this review, we analyze the molecular contribution of inflammation and the coagulation system on PAD pathogenesis, focusing on molecular similarities and differences between atherogenesis in PAD and coronary artery disease (CAD) and discussing the possible implications for current therapeutic strategies and future perspectives accounting for molecular inflammatory and coagulation targets. Understanding the role of cross-talking between coagulation and inflammation in atherosclerosis genesis and progression could help in choosing the right patients for future dual pathway inhibition strategies, where an antiplatelet agent is combined with an anticoagulant, whose role, despite pathophysiological premises and trials' results, is still under debate.

Nanomechanics of Blood Clot and Thrombus Formation

Mechanical properties have been extensively studied in pure elastic or viscous materials; however, most biomaterials possess both physical properties in a viscoelastic component. How the biomechanics of a fibrin clot is related to its composition and the microenvironment where it is formed is not yet fully understood. This review gives an outline of the building mechanisms for blood clot mechanical properties and how they relate to clot function. The formation of a blood clot in health conditions or the formation of a dangerous thrombus go beyond the mere polymerization of fibrinogen into a fibrin network. The complex composition and localization of in vivo fibrin clots demonstrate the interplay between fibrin and/or fibrinogen and blood cells. Studying these protein–cell interactions and clot mechanical properties may represent new methods for the evaluation of cardiovascular diseases (the leading cause of death worldwide), creating new possibilities for clinical diagnosis, prognosis, and therapy.

Expected final online publication date for the Annual Review of Biophysics, Volume 51 is May 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

The effect of hyperoxia on the hemostasiological status of severely burned patients

The state of the hemostasis system was studied in 9 patients of the middle age group (44 ± 9.94 years) who received thermal trauma on an area of more than 32% (49.4 ± 18.3) of the body surface, accompanied by the development of burn shock. The standard therapy for burn injury was supplemented with HBO sessions. Treatment with hyperbaric oxygen was carried out in pressure chambers BLKS-307, BLKS-307/1. The state of the coagulation, anticoagulant and fibrinolytic links of the hemostasis system, as well as the viscoelastic properties of the blood, were assessed immediately before the HBO session and immediately after it. The total number of comparison pairs was 45. Under the influence of HBO therapy, there was an increase in the activity of antithrombin III (ATIII), protein C (PrS) and a decrease in the viscoelastic properties of blood (p <0.05). Positive deviations in the values of ATIII, Pr C, von Willebrand factor, APTT, prothrombin and thrombin time, fibrinogen, factor XIII, XIIa-dependent fibrinolysis, D-dimers and thromboelastography parameters were revealed. The maximum frequency of their occurrence was recorded for ATIII (95%), the minimum - for the D-dimer (62%). After HBO procedures, undesirable deviations of the hemostatic system parameters were also noted. They were chaotic, were compensated by an increase in the activity of physiological anticoagulants and were not accompanied by complications of a thrombogenic nature. Thus, conducting HBO therapy sessions in the acute period of burn disease increases the activity of physiological anticoagulants and stabilizes the viscoelastic properties of blood. There is a high frequency of occurrence of positive effects of hyperoxia on the components of the hemostasis system. The identification of its undesirable effects indicates the need to monitor the state of the hemostasis system during HBO procedures.

Antithrombotic Therapy in Patients with Peripheral Artery Disease: A Focused Review on Oral Anticoagulation

Peripheral artery disease (PAD) is a major cause of morbidity and mortality but it is usually underdiagnosed and undertreated. Patients with PAD present dysregulated procoagulant, anticoagulant, and fibrinolytic pathways leading to arterial and venous thrombosis. The risk of several ischemic-related complications could be mitigated with appropriate antithrombotic therapy, which plays a central role in all types of PAD. For years, antiplatelets have been indicated in patients with symptomatic PAD or those who have undergone revascularization. Unfortunately, a non-negligible proportion of patients with PAD will suffer from adverse events during the follow-up, even despite proper medical therapies for the prevention of PAD complications. Thus, there is room for improving clinical outcomes in these patients. Given the implication of both, primary and secondary hemostasis in arterial thrombosis and the pathophysiology of PAD, the combination of antiplatelets and anticoagulants has emerged as a potential antithrombotic alternative to antiplatelets alone. In this narrative review article, we have highlighted the most recent evidence about antithrombotic therapy in PAD patients, with a special focus on oral anticoagulation. Certainly, COMPASS and VOYAGER PAD trials have shown promising results. Thus, rivaroxaban in combination with aspirin seem to reduce cardiovascular outcomes with a similar bleeding risk compared to aspirin alone. Nevertheless, results from real-world studies are needed to confirm these observations, and other trials will provide novel evidence about the safety and efficacy of emerging anticoagulant agents.

The interrelationship between pregnancy, venous thromboembolism, and thyroid disease: a hypothesis-generating review

Pregnancy induces physiological changes that affect the risk of thrombosis and thyroid disease. In this hypothesis-generating review, the physiological changes in the coagulation system and in thyroid function during a normal pregnancy are described, and the incidence of venous thromboembolism (VTE) and thyroid disease in and after a pregnancy are compared and discussed. Furthermore, evidence regarding the association between thyroid disease and VTE in non-pregnant individuals is scrutinized. In conclusion, a normal pregnancy entails hormonal changes, which influence the onset of VTE and thyroid disease. Current evidence suggests an association between thyroid disease and VTE in non-pregnant individuals. This review proposes the hypothesis that maternal thyroid disease associates with VTE in pregnant women and call for future research studies on this subject. If an association exists in pregnant women specifically, such findings may have clinical implications regarding strategies for thyroid function testing and potential thromboprophylaxis in selected individuals.