Seminars in thrombosis and hemostasis最新文献

C1-inhibitor deficiency-associated hereditary angioedema (C1INH-HAE) is a rare congenital swelling disorder caused by mutations in the SERPING1 gene. Despite evidence of a systemic procoagulant state in C1INH-HAE, dogma held that this disorder was not associated with thrombotic pathologies. Recent population scale epidemiological evidence has directly challenged this, with C1INH-HAE being associated with a significantly increased risk of venous thromboembolism (VTE). This review considers the growing body of evidence supporting associations between HAE and both a systemic procoagulant state and an increased risk of VTE. In the setting of C1INH-HAE, the relationship between the observed procoagulant and thrombotic phenotypes is a prime example of "where there's smoke, there's fire." This review also discusses the impact of C1INH-HAE disease modifying therapies on coagulation and VTE. Further, the utility of preclinical mouse models of C1-inhibitor deficiency is considered.

Venous thromboembolism (VTE) after hospital discharge poses a serious health risk. Assessments of patient characteristics, prophylaxis, treatment, outcomes, and over time changes lack consistency. Data on 16,901 hospitalized patients in the Registro Informatizado Enfermedad TromboEmbolica registry (2003-2022) were analyzed to evaluate trends in baseline characteristics, prophylaxis, treatments, and 90-day outcomes among medical (6,218) and surgical (10,683) patient cohorts. Multivariable logistic regression was used to assess the risks of the composite of fatal pulmonary embolism (PE) or recurrent VTE and major bleeding. The proportion of patients who presented with PE increased among medical (from 54 to 72%) and surgical patients (from 55 to 58%). Prophylaxis use increased in medical patients (from 53 to 71%), while decreasing in surgical patients (from 67 to 58%). Notably, the 90-day composite of fatal PE or recurrent VTE decreased in medical (from 3.9 to 1.8%) and surgical patients (from 2.9 to 1.2%; p < 0.001 for both). Conversely, major bleeding increased (3.1 to 4.5%) in medical patients (p = 0.008), with no change in surgical patients (from 2.5 to 2.4%). Risk-adjusted analysis showed a yearly decrease in the risk for the composite outcome (subhazard ratio [sHR]: 0.95; 95% confidence interval [CI]: 0.93-0.98) in medical and surgical patients and an increase in the risk for major bleeding in medical patients only (sHR: 1.04; 95% CI: 1.01-1.07). Results were consistent after excluding coronavirus disease 2019 patients. Over 20 years, the composite of fatal PE or recurrent VTE within 90 days had significantly decreased in VTE patients after hospitalization for medical or surgical care. Medical patients, however, exhibited an increase in major bleeding.

Apical ballooning syndrome, commonly known as Takotsubo syndrome, is a distinct cardiomyopathy often resembling acute myocardial infarction in presentation. Takotsubo syndrome patients exhibit varied patterns of left ventricular wall motion abnormalities, most frequently apical dyskinesis with basal hyperkinesis, that are characteristically transient. Although emotional or physical stressors precipitate Takotsubo syndrome in most cases, a significant proportion presents without identifiable triggers, with a pronounced female predominance. Despite recovery of left ventricular function, Takotsubo syndrome may lead to serious complications akin to acute coronary syndromes. The pathophysiology remains incompletely understood, with catecholamine surge implicated in the genesis of myocardial injury, although direct causation remains debated. Diagnosis involves integrating clinical history, imaging modalities like echocardiography, and cardiac MRI. Psychiatric disorders, particularly anxiety and depression, are frequently associated with Takotsubo syndrome, suggesting a role of chronic stress in disease susceptibility. Management includes supportive care, with anticoagulation considered in cases of apical thrombus, alongside close monitoring for complications and recovery of left ventricular function. This article reviews the current understanding, challenges in diagnosis, and management strategies for Takotsubo syndrome.

The CD40-CD40L receptor ligand pair plays a fundamental role in the modulation of the innate as well as the adaptive immune response, regulating monocyte, T and B cell activation, and antibody isotype switching. Although the expression and function of the CD40-CD40L dyad is mainly attributed to the classical immune cells, the majority of CD40L is expressed by activated platelets, either in a membrane-bound form or shed as soluble molecules in the circulation. Platelet-derived CD40L is involved in the communication with different immune cell subpopulations and regulates their functions effectively. Thus, platelet CD40L contributes to the containment and clearance of bacterial and viral infections, and additionally guides leukocytes to sites of infection. However, platelet CD40L promotes inflammatory cellular responses also in a pathophysiological context. For example, in HIV infections, platelet CD40L is supportive of neuronal inflammation, damage, and finally HIV-related dementia. In sepsis, platelet CD40L can induce extensive endothelial and epithelial damage resulting in barrier dysfunction of the gut, whereby the translocation of microbiota into the circulation further aggravates the uncontrolled systemic inflammation. Nevertheless, a distinct platelet subpopulation expressing CD40L under septic conditions can attenuate systemic inflammation and reduce mortality in mice. This review focuses on recent findings in the field of platelet CD40L biology and its physiological and pathophysiological implications, and thereby highlights platelets as vital immune cells that are essential for a proper immune surveillance. In this context, platelet CD40L proves to be an interesting target for various inflammatory diseases. However, either an agonism or a blockade of CD40L needs to be well balanced since both the approaches can cause severe adverse events, ranging from hyperinflammation to immune deficiency. Thus, an interference in CD40L activities should be likely done in a context-dependent and timely restricted manner.

Intravenous direct thrombin inhibitors (DTIs) are used for thromboembolic disorders. This systematic review aims to characterize intravenous DTI agents, dosing, monitoring strategies (or use), bleeding, and mortality, in pediatric patients with acute venous thromboembolism (VTE) or heparin-induced thrombocytopenia with thrombosis (HITT). MEDLINE, Embase, and Cochrane's CENTRAL were searched from inception through July 2023. Case series, retrospective studies, and prospective studies providing per-patient or summary data for patients < 18 years of age with VTE or HITT treated with an intravenous DTI were included. Selection and data extraction were conducted independently by two reviewers. Sixteen studies (7 case reports, 1 case series, 5 retrospective studies, 3 prospective studies) with 85 patients were included. Target conditions included acute VTE in 54 (64%) and HITT in 31 (36%) patients. Bivalirudin, argatroban, and lepirudin were used in 52 (61%), 27 (32%), and 6 (7%) patients, respectively. Fifty-two (61%) patients received a bolus dose, and weighted mean infusion rates for bivalirudin, argatroban, and lepirudin were 0.2 mg/kg/hr, 1.2 mcg/kg/min, and 0.15 mg/kg/hr, respectively. The activated partial thromboplastin time was utilized for monitoring in 82 (96%) patients. Complete or partial thrombus resolution was reported in 53 (62%) patients, mortality in 6 (7%) patients, and bleeding complications in 14 (16%) patients. In this systematic review involving 85 pediatric patients treated with an intravenous DTI for acute VTE or HITT, bivalirudin was the most commonly utilized agent, with a rate of resolution over 60% despite a high acuity in the population studied. Prospective collaborative studies are warranted to establish optimal dosing and further characterize VTE and bleeding outcomes.

Antiphospholipid syndrome (APS) diagnosis hinges on identifying antiphospholipid antibodies (aPL). Currently, laboratory testing encompasses lupus anticoagulant (LA), anticardiolipin (aCL), and anti-β2-glycoprotein I antibodies (aβ2GPI) IgG or IgM, which are included in the APS classification criteria. All the assays needed to detect aPL antibodies have methodological concerns. LA testing remains challenging due to its complexity and susceptibility to interference from anticoagulant therapy. Solid phase assays for aCL and aβ2GPI exhibit discrepancies between different assays. Antibody profiles aid in identifying the patients at risk for thrombosis through integrated interpretation of all positive aPL tests. Antibodies targeting domain I of β2-glycoprotein and antiphosphatidylserine-prothrombin antibodies have been evaluated for their role in thrombotic APS but are not yet included in the APS criteria. Detecting these antibodies may help patients with incomplete antibody profiles and stratify the risk of APS patients. The added diagnostic value of other methodologies and measurements of other APS-associated antibodies are inconsistent. This manuscript describes laboratory parameters useful in the diagnosis of thrombotic APS and will concentrate on the laboratory aspects, clinical significance of assays, and interpretation of aPL results in the diagnosis of thrombotic APS.

The contact pathway of blood clotting has received intense interest in recent years as studies have linked it to thrombosis, inflammation, and innate immunity. Because the contact pathway plays little to no role in normal hemostasis, it has emerged as a potential target for safer thromboprotection, relative to currently approved antithrombotic drugs which all target the final common pathway of blood clotting. Research since the mid-2000s has identified polyphosphate, DNA, and RNA as important triggers of the contact pathway with roles in thrombosis, although these molecules also modulate blood clotting and inflammation via mechanisms other than the contact pathway of the clotting cascade. The most significant source of extracellular DNA in many disease settings is in the form of neutrophil extracellular traps (NETs), which have been shown to contribute to incidence and severity of thrombosis. This review summarizes known roles of extracellular polyphosphate and nucleic acids in thrombosis, with an emphasis on novel agents under current development that target the prothrombotic activities of polyphosphate and NETs.