High prevalence of thrombophilic risk factors in patients with central retinal artery occlusion.

INTRODUCTION: Central retinal artery occlusion (CRAO) is a common cause of blindness and visual morbidity. In the majority of cases, it is related to thrombotic embolism. Nevertheless, the role of inherited or acquired thrombophilic risk factors in CRAO pathogenesis has not been comprehensively studied. METHODS: In 126 CRAO patients (66 [52.4%] men, median age 55 [range: 18-80] years) and 107 matched controls (56 [52.3%] men, median age 53 [range: 34-78] years) we evaluated classical atherosclerotic risk factors, including serum lipid profile and glucose level, analyzed intima-media complex thickness (IMT) of external carotid arteries, and performed transthoracic echocardiography. Furthermore, we established the prevalence of inherited and acquired thrombophilic risk factors, such as factor V Leiden (FVL) and prothrombin 20210 G/A genetic variants, plasma activity of factor (F) VIII, protein C and antithrombin activity, and free protein S levels. We also assessed the presence of antiphospholipid antibodies (APLA) and evaluated blood homocysteine in all enrolled subjects. Additionally, we estimated the occurrence of Val34Leu polymorphism of the A subunit of coagulation factor XIII (FXIII-A) in both groups as a potential thrombosis-protecting factor. RESULTS: Among traditional atherosclerotic risk components, obesity/overweight and hypercholesterolemia were the most common in the CRAO group and occurred in 103 (81.7%) and 85 (67.5%) patients, respectively. CRAO patients also had elevated IMT and altered echocardiographic parameters, indicating diastolic cardiac dysfunction. In thrombophilia investigations, at least one laboratory risk factor occurred in 72.2% (n = 91) of CRAO patients, with APLA as the most frequent, detected in 38.1% (n = 48) of them (almost seven times more frequent than in controls, p < 0.001). Deficiencies in protein C activity and free protein S levels were also common in the CRAO group, reported in 17.5% (n = 22) and 19.8% (n = 25) of patients, respectively. Interestingly, among two analyzed prothrombotic genetic variants, only the FVL was related to CRAO, with the allelic frequency 2.4 times more prevalent than in controls (p = 0.044). Finally, the CRAO group was characterized by hyperhomocysteinemia, almost twice as common as in controls (p = 0.026). Antithrombin deficiency, elevated FVIII, and FXIII-A Val34Leu polymorphism were not associated with CRAO. CONCLUSIONS: Our findings suggest that thrombophilia plays a vital role in the pathogenesis of CRAO. Thus, proper laboratory screening should be considered in the primary and secondary prevention of those episodes, with implementing appropriate therapy as needed.

Afibrinogenemia caused by a novel homozygous missense mutation, FGB p.Cys241Tyr, in a male patient with recurrent intracranial bleeding: case report and review of literature.

INTRODUCTION: Congenital afibrinogenemia is a severe bleeding disorder, sometimes manifesting as thrombosis and/or pregnancy complications. Intracranial haemorrhage (ICH) constitutes the major cause of death in this disease. METHODS: We present the case of a male patient with congenital afibrinogenemia, who presented with recurrent intracranial hemorrhages, despite prophylactic fibrinogen substitution. We also review the literature for the risk of intracranial hemorrhages in afibrinogenemia. RESULT: Molecular analysis revealed a novel homozygous missense mutation in FGB exon 5, p.Cys241 Tyr, that was named "Fibrinogen Krakow V". DISCUSSION AND CONCLUSION: Intracranial hemorrhage is a severe manifestation of afibrinogenemia, also in children. The clinical presentation of afibrinogenemia is variable. Fibrinogen substitution carries a risk of thrombotic complications.

Thrombin generation potential is enhanced in systemic sclerosis: impact of selected endothelial biomarkers.

OBJECTIVES: Systemic sclerosis (SSc) is a rare immune-mediated heterogenous entity characterised by excessive tissue fibrosis and vascular injury. Recently, increased risk of thromboembolic events has been documented in that disease. Our aim was to investigate prothrombotic plasma properties together with selected laboratory biomarkers of endothelial injury in SSc. METHODS: In 56 clinically stable SSc patients and 67 well-matched controls we assessed plasma thrombin generation profile and measured circulating vascular cell adhesion molecule-1 (VCAM-1), cellular fibronectin (cFN), and thrombomodulin, as well as analysed their relationships with disease clinical parameters and autoimmune antibodies profile. RESULTS: SSc was characterised by 18.3% increased endogenous thrombin potential (ETP), 14.5% higher thrombin peak (p<0.001 both, also after adjustment for potential confounders), and similar endothelial damage biomarkers, as compared to controls. Surprisingly, raised thrombin generation was related to the lower thrombomodulin and VCAM-1. Inflammatory markers, factor VIII activity, and blood eosinophilia predicted positively ETP, whereas platelet count and thrombomodulin had negative impact on that parameter in a multiple regression model. Intriguingly, patient group had also 6.7% extended lag-time (p=0.01 after adjustment for confounders) which was independently determined by higher thrombomodulin and cFN, as well as lower VCAM-1. Former cyclophosphamide therapy, thus more severe type of the disease was referred to the increased thrombin generation. CONCLUSIONS: SSc is characterised by enhanced thrombin generation potential which might contribute to the higher risk of thromboembolic events in that disease. Endothelium may play hereby an additional role, although large observational and experimental studies are needed to verify this hypothesis.

Perioperative cardiovascular complications rate and activity of coagulation and fibrinolysis among patients undergoing vascular surgery for peripheral artery disease and abdominal aortic aneurysm.

OBJECTIVES: To compare preoperative coagulation and fibrinolysis activity and incidence of perioperative complications between patients undergoing vascular procedures for peripheral artery disease and abdominal aortic aneurysm. METHODS: This is a substudy of a prospective observational cohort study (VISION; NCT00512109) in which we recruited patients aged ≥45 years, undergoing surgery for peripheral artery disease and abdominal aortic aneurysm. Blood samples were obtained 24 h preoperatively to measure platelet count, concentrations of coagulation coagulation (fibrinogen, factor VIII, von Willebrand factor:Ristocetin cofactor, antithrombin III), fibrinolysis (dimer D, plasmin-antiplasmin complexes, tissue plasminogen activator) markers and level of soluble CD40 ligand. Incidence of myocardial infarction, stroke, and death (composite endpoint) was assessed in 30-day follow-up. RESULTS: The study group included 131 patients at the mean age of 68.3 years among whom reason for surgery was peripheral artery disease in 77 patients (58.8%) and abdominal aortic aneurysm in 54 patients (41.2%). Peripheral artery disease group was characterized by higher platelet count (250.5 versus 209.5 (×103/µl), p = 0.001), concentrations of fibrinogen (5.4 versus 4.1 (g/l), p < 0.001), factor VIII (176.9 versus 141.9 (%), p < 0.001), von Willebrand factor:Ristocetin cofactor (188.9 versus 152.3 (%), p = 0.009), and soluble CD40 ligand (9016.0 versus 7936.6 (pg/ml), p = 0.005). The dimer D level was higher (808.0 versus 2590.5 (ng/ml), p < 0.001) in the abdominal aortic aneurysm group. Incidence of major cardiovascular events (death, myocardial infarction, stroke) within 30 days from surgery did not differ between the groups (39.0% versus 29.6%, p = 0.27). CONCLUSIONS: The study suggests higher activation of coagulation and relatively lower fibrinolytic activity in peripheral artery disease group compared to patients undergoing surgery for abdominal aortic aneurysm without a significant difference in cardiovascular outcomes.

Endothelial dysfunction in patients with systemic sclerosis.

INTRODUCTION: Patients with systemic sclerosis experience endothelial dysfunction and damage even in the absence of clinical manifestations. AIM: To evaluate various methods for assessing the endothelial function for their applicability to clinical practice. MATERIAL AND METHODS: Forty-two patients (7 men and 35 women) with systemic sclerosis and 36 controls (11 men and 25 women) matched for age, sex, body mass index, smoking habit, and comorbidities were enrolled in the study. We assessed each participant for typical risk factors for cardiovascular diseases and measured serum levels of vascular cell adhesion molecule-1 (VCAM-1) and thrombomodulin together with flow-mediated dilatation (FMD) of the brachial artery and intima-media thickness (IMT) of the common carotid artery using ultrasonography. RESULTS: Patients with systemic sclerosis did not differ from controls in serum levels of VCAM-1 and thrombomodulin, however, the statistical analysis with adjustment for potential confounders revealed increased levels of thrombomodulin in the patients (p = 0.03). They also had a 45% lower relative increase of FMD (FMD%), and 13% higher IMT (p < 0.01, both, also after adjustment for potential confounders). In a simple regression model, lower FMD% was determined by age (ß = -0.57, 95% confidence interval (CI): -0.72 to -0.43) and C-reactive protein levels (ß = -0.38, 95% CI: -0.55 to -0.22). Thicker IMT was related to age (ß = 0.64, 95% CI: 0.52-0.67), glomerular filtration rate (ß = -0.34, 95% CI: -0.5 to -0.18), and blood thrombomodulin levels (ß = 0.45, 95% CI: 0.13-0.76). CONCLUSIONS: Patients with systemic sclerosis present with endothelial dysfunction which may be detected using ultrasonographic methods. The exact mechanism of observed abnormalities is unknown, but it is possibly related to the chronic inflammation and ischemia-reperfusion injury.

Restenosis is associated with prothrombotic plasma fibrin clot characteristics in endovascularly treated patients with critical limb ischemia.

INTRODUCTION: Hypolysible fibrin clots composed of tightly packed fibers characterize patients with peripheral artery disease (PAD) especially those with critical limb ischemia (CLI). Little is known about the impact of a prothrombotic clot phenotype on restenosis following endovascular revascularization in CLI. The goal of this study was to compare fibrin clot properties and their determinants in CLI patients with restenosis after endovascular treatment (ET) and those free of this complication. METHODS: 85 patients with CLI and restenosis within 1 year after ET on optimal pharmacotherapy and 47 PAD control patients without restenosis were included into the study. Plasma fibrin clot permeability (Ks, a measure of the average pore size in the fibrin network) and clot lysis time (CLT) with its potential determinants were determined. During follow-up, the composite endpoint including re-intervention, amputation and death was assessed. RESULTS: Compared with the control group, patients with restenosis had reduced Ks (- 9.5%, p < 0.001), prolonged CLT (+ 12.4%, p = 0.003), higher thrombin generation (+ 7.9%, p < 0.001) and elevated von Willebrand factor (vWF) antigen (+ 14.2%, p < 0.001). During a 24 months follow-up the composite endpoint occurred in 54 CLI patients with restenosis (63.5%) and nine control patients (19.1%, p < 0.001) with no association with baseline Ks and CLT. CONCLUSION: The increased thrombin formation and unfavorable fibrin clot properties occur in patients with CLI who experienced restenosis despite optimal endovascular and pharmacological therapy.

Reduced plasma fibrin clot permeability is associated with recurrent thromboembolic events in patients with antiphospholipid syndrome.

Objectives: APS is associated with arterial and venous thrombosis. The unfavourable fibrin clot phenotype, including formation of dense and poorly lysable clots, has been reported in thrombotic APS. We investigated whether abnormal plasma clot properties are predictive of recurrent thromboembolism in APS. Methods: We followed 126 consecutive patients with thrombotic APS and 105 control subjects, without APS, matched for thrombotic events. Plasma fibrin clot permeability (Ks), turbidity measurements and clot lysis time were evaluated ⩾5 months after a thrombotic event. The primary composite end point was symptomatic recurrent venous thromboembolism, ischaemic stroke and/or myocardial infarction. Results: During follow-up (median, 62 months; range 46-74 months; 1183.2 patient-years), the primary outcome was observed in 33 (26.2%) APS patients and 16 (15.2%) controls, including 25 (19.8%) and 14 (13.3%) subjects with recurrent venous thromboembolism, respectively. Reduced Ks and prolonged clot lysis time predicted recurrent thromboembolic events in APS patients [per 1 × 10-9 cm2: hazard ratio (HR) = 0.37; 95% CI: 0.24, 0.56; and per 10 min: HR = 1.20; 95% CI: 1.01, 1.40, respectively] and in controls (per 1×10-9 cm2: HR = 0.23; 95% CI: 0.11, 0.42; and per 10 min: HR = 1.51; 95% CI: 1.08, 2.16, respectively). A multivariate analysis showed that positive IgG and IgM anti-ß2 glycoprotein I antibodies, withdrawal of anticoagulation, lower platelet count and reduced Ks predicted thromboembolic events in APS patients. Conclusion: Formation of denser fibrin networks could be a novel risk factor for recurrent thromboembolism in APS, which highlights the importance of fibrin phenotype in thrombotic disorders.

Endothelial dysfunction in patients with granulomatosis with polyangiitis: a case-control study.

BACKGROUND: Granulomatosis with polyangiitis (GPA) is a rare granulomatous vasculitis affecting small- and medium-sized blood vessels. In optimally treated patients with long-standing disease, the common cause of death is atherosclerosis even in the absence of typical risk factors. OBJECTIVE: To evaluate endothelial dysfunction in GPA patients. METHODS: 44 patients (21 men and 23 women) diagnosed with GPA and 53 controls matched for age, sex, BMI and typical risk factors for cardiovascular diseases (22 men and 31 women) were enrolled in the study. We measured each participant's serum levels of vascular cell adhesion molecule-1 (VCAM-1), interleukin 6 (IL-6), and thrombomodulin. We also studied flow-mediated dilatation (FMD) of the brachial artery, intima-media thickness (IMT) of the common carotid artery and aortic stiffness using echocardiography. RESULTS: Patients with GPA showed a 15.9% increase in serum levels of VCAM-1 (p = 0.01), 66% of IL-6 (p < 0.001) and 50.9% of thrombomodulin (p < 0.001) compared to controls. FMD% was 48.9% lower in patients with GPA in comparison to controls (p < 0.001), after adjustment for potential confounders, with no differences regarding IMT or aortic stiffness. FMD% was negatively associated with duration of the disease (ß = - 0.18 [95% CI: - 0.32 to - 0.04]), C-reactive protein (ß = - 0.17 [95% CI: - 0.27 to - 0.07]), IL-6 (ß = - 0.29 [95% CI: - 0.39 to - 0.19]), blood creatinine level (ß = - 0.2 [95% CI: - 0.3 to - 0.1]), and IMT (ß = - 0.14 (- 0.24 to - 0.04). In a multiple linear regression model, kidney function, IMT, pack-years of smoking, diabetes and level of VCAM-1 were independent predictors of lower FMD%. CONCLUSION: GPA is characterized by endothelial dysfunction. FMD is a useful tool for the detection of endothelial injury.

Antiphospholipid and Antinuclear Antibodies in Young Patients after Myocardial Revascularization Procedures.

BACKGROUND: The role of autoimmune factors in the etiology of coronary artery disease (CAD) was suggested in numerous studies but has not been definitively determined. OBJECTIVES: To assess the possible influence of antiphospholipid and antinuclear antibodies on atherosclerosis development in young patients after myocardial revascularization procedures. METHODS: The study group included 39 patients younger than 45 years with CAD who underwent myocardial revascularization. Serum levels of antiphospholipid (aPL), antinuclear (ANA) and antineutrophil cytoplasmatic (ANCA) antibodies were tested within 1 month after the procedure. RESULTS: All three types of aPL were significantly higher in CAD patients when compared to healthy controls: anti-ß2-glycoprotein I (aß2GPI), both immunoglobulin (Ig)G and IgM classes (median 4.10 SGU, range 3.45-21.63 vs. 0.76, 0.12-6.01, P < 0.001, and 2.82 SGU, 1.44-11.70 vs. 1.08, 0.44-3.64, P < 0.001, respectively); anticardiolipin antibodies (aCL) both IgG and IgM classes (3.13 GPL, 1.32-14.03 vs. 2.42, 0.96-18.45, P = 0.0037, and 6.94 MPL, 1.90-26.40 vs. 4.32, 1.9-28.73, P < 0.008, respectively); and lupus anticoagulant (LA) (27.7% vs. 0%, P = 0.005). ANA were elevated in one patient and ANCA in 23 (60%). The levels of aPL did not correlate with the presence of a clot in a coronary vessel detected during angiography or with exacerbation of coronary artery atherosclerosis. CONCLUSIONS: In young patients with CAD who underwent myocardial revascularization the levels of aPL were significantly higher than in young healthy subjects. Thus, besides the classic risk factors for CAD, autoimmunity may play an important role in atherosclerotic plaque formation and progression.

Temporal changes of hemostatic activity in patients hospitalized for COVID-19: a prospective observational study.

INTRODUCTION: Hemostatic abnormalities play an important role in the pathogenesis of COVID­19 and are considered determinants of the patients' outcomes. Less is known about the dynamics of these abnormalities in a short­term observation. OBJECTIVES: The aim of the study was to evaluate hemostatic activity markers in patients hospitalized for COVID­19 depending on the severity of respiratory failure. PATIENTS AND METHODS: This was a prospective observational study enrolling adult patients hospitalized for COVID­19 in a tertiary center in Poland, from January to May 2021. Blood samples were drawn upon admission and 28 days after the admission to measure the markers of coagulation, fibrinolysis, and endothelial dysfunction, and to evaluate whether there are significant differences between these 2 time points. All analyses were performed in the entire cohort and after stratification into 3 groups depending on the degree of respiratory support. RESULTS: We recruited 245 patients at the median age of 63 years (interquartile range, 52-69), among whom 158 (64.5%) were men. The analysis of hemostatic markers on admission revealed that hypercoagulability, hypofibrinolysis, and endothelial dysfunction are related to the degree of respiratory support. We found significant differences between the admission and 28­day follow­up in all markers except for plasminogen activity. Interestingly, the markers of endothelial dysfunction remained the highest in the advanced respiratory support group after 28 days, while differences in the other markers diminished. CONCLUSION: Hemostatic abnormalities are significantly attenuated within a month after a hospital admission due to COVID­19. The initially observed association between severity of the disease and hemostatic derangements persists only for the markers of endotheliopathy.

Decreased protein C activity, lower ADAMTS13 antigen and free protein S levels accompanied by unchanged thrombin generation potential in hospitalized COVID-19 patients.

INTRODUCTION: COVID-19 is associated with an increased thromboembolic risk. However, the mechanisms triggering clot formation in those patients remain unknown. PATIENTS AND METHODS: In 118 adult Caucasian severe but non-critically ill COVID-19 patients (median age 58 years; 73 % men) and 46 controls, we analyzed in vitro plasma thrombin generation profile (calibrated automated thrombogram [CAT assay]) and investigated thrombophilia-related factors, such as protein C and antithrombin activity, free protein S level, presence of antiphospholipid antibodies and factor V Leiden R506Q and prothrombin G20210A mutations. We also measured circulating von Willebrand factor (vWF) antigen and a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13 (ADAMTS13) antigen and activity. In patients, blood samples were collected on admission to the hospital before starting any therapy, including heparin. Finally, we examined the relationship between observed alterations and disease follow-up, such as thromboembolic complications. RESULTS: COVID-19 patients showed 17 % lower protein C activity, 22 % decreased free protein S levels, and a higher prevalence of positive results for IgM anticardiolipin antibodies. They also had 151 % increased vWF, and 27 % decreased ADAMTS13 antigens compared with controls (p < 0.001, all). On the contrary, thrombin generation potential was similar to controls. In the follow-up, pulmonary embolism (PE) occurred in thirteen (11 %) patients. They were characterized by a 55 % elevated D-dimer (p = 0.04) and 2.7-fold higher troponin I (p = 0.002) during hospitalization and 29 % shorter time to thrombin peak in CAT assay (p = 0.009) compared to patients without PE. CONCLUSIONS: In COVID-19, we documented prothrombotic abnormalities of peripheral blood. PE was characterized by more dynamic thrombin generation growth in CAT assay performed on admittance to the hospital.

Influence of statin therapy on antiphospholipid antibodies and endothelial dysfunction in young patients with coronary artery disease and systemic lupus erythematosus.

INTRODUCTION: Antiphospholipid antibodies (aPL) affect atherogenesis and may cause thromboembolism in systemic lupus erythematosus (SLE) and coronary artery disease (CAD). Intensive treatment with statins may reduce inflammation and decrease the number of thrombotic events. That may explain the beneficial effect of statin therapy in SLE and CAD. This study was established to investigate the influence of statin treatment on aPL antibody levels and selected endothelial dysfunction markers in CAD and SLE patients. MATERIAL AND METHODS: Fifty-eight patients - 40 after coronary revascularization (age 38.9 (27-46), 35 males) and 18 with clinically stable SLE (age 38.8 (18-62), 1 male) - were enrolled in the study. In both groups intensive atorvastatin treatment was administered. At baseline and after 1 year of follow-up serology tests were performed: anticardiolipin antibodies (aCL), anti-ß2 glycoprotein I (aß2GPI), lupus anticoagulant (LA), C-reactive protein (CRP), soluble form of intracellular adhesion molecule-1 (sICAM-1), vWF:Ag. RESULTS: Coronary artery disease patients in 1 year follow-up revealed a decrease of aß2GPI IgG and CRP. There was a significant increase in aCL IgG, sICAM-1 and vWF:Ag. In SLE patients aPL levels showed no significant reduction after treatment. CONCLUSIONS: In clinically stable patients IgM and IgG class aß2GPI levels are higher in CAD than in SLE, whereas IgG class aCL levels are lower. Statin treatment decreases the CRP level in both SLE and CAD patients, while decreasing the aß2GPI IgG level only in CAD patients.

Central Retinal Artery Occlusion Is Related to Vascular Endothelial Injury and Left Ventricular Diastolic Dysfunction.

Central retinal artery occlusion (CRAO) is an emergency state characterized by sudden, painless vision impairment. Patients with CRAO have an increased risk of cardiovascular events, including stroke, likely related to vascular endothelial damage. Therefore, we investigated flow-mediated dilatation (FMD) of the brachial artery as a marker of endothelial dysfunction, intima-media complex thickness (IMT) of the common carotid artery, pointing to the arterial wall atherosclerotic alteration, and transthoracic echocardiographic parameters in 126 consecutive CRAO patients (66 men [52.4%], median age 55 years) and 107 control participants (56 men [52.3%], matched by age, sex, and body mass index). Most CRAO patients (n = 104, 82.5%) had at least one internal medicine comorbidity, mainly hypercholesterolemia and hypertension, which coexisted in one-fourth of them. Furthermore, they had a 38.2% lower relative increase of FMD (FMD%) and a 23.1% thicker IMT compared to the controls (p < 0.001, both, also after adjustment for potential confounders). On echocardiography, the CRAO group was characterized by increased dimensions of the left atrium and thicker left ventricular walls, together with impaired left ventricular diastolic function. CRAO is related to vascular endothelial damage, atherosclerosis, and left ventricular diastolic cardiac dysfunction. Thus, non-invasive ultrasound assessments, such as FMD%, IMT, and echocardiography, may be helpful in screening patients with increased CRAO risk, particularly those with other comorbidities.

Prothrombotic state, endothelial injury, and echocardiographic changes in non-active sarcoidosis patients.

Sarcoidosis is a multisystem inflammatory granulomatous disease of unknown cause that most commonly affects lungs and lymph nodes, with frequent yet asymptomatic cardiac involvement. The epidemiologically associated cardiovascular risk suggests an underlying prothrombotic state and endothelial dysfunction, currently understudied in the available literature. Therefore, we aimed to investigate prothrombotic plasma properties together with selected echocardiographic and laboratory biomarkers of cardiovascular injury in that disease. N = 53 patients with pulmonary sarcoidosis in clinical remission and N = 66 matched controls were assessed for inflammatory and endothelial injury biomarkers, plasma thrombin generation profile, and echocardiographic and lung function parameters. Sarcoidosis cases had impaired systolic and diastolic left ventricular function, higher concentrations of inflammatory markers, D-dimer and factor VIII activity compared to the controls. The coexistence of extrapulmonary disease was associated with elevated circulating vascular cell adhesion molecule 1, while cases with hypercalcemia had higher thrombomodulin concentration. Sarcoidosis was characterized by the unfavorably altered thrombin generation profile, reflected by the 16% higher endogenous thrombin potential (ETP), 24% increased peak thrombin concentration, and 12% shorter time to thrombin peak in comparison to the control group. ETP was higher in cases with proxies of pulmonary restriction, extrapulmonary-extracutaneous manifestation, and need for corticosteroids use. Despite the clinical remission, sarcoidosis is related to prothrombotic plasma properties and signs of endothelial injury, likely contributing to the higher risk of cardiovascular events. In addition, subclinical cardiac involvement may play an additional role, although further clinical and experimental studies are needed to verify these findings.

Thrombin generation potential is increased in patients with autoimmune inflammatory myopathies.

PURPOSE: Dermatomyositis and polymyositis (DM/PM) are rare autoimmune inflammatory myopathies, characterized by an increased risk of cardiovascular and thromboembolic events, likely related to the prothrombotic plasma properties. The aim of this study was to assess the in vitro thrombin generation profile as a biomarker of plasma procoagulant properties in DM/PM patients. METHODS: In 58 clinically stable DM/PM patients and 67 controls matched for sex, age, body mass index, we measured plasma thrombin generation potential using the Calibrated Automated Thrombinography (CAT) and analyzed its relationship with clinical disease characteristics, including autoantibodies profile. RESULTS: Patients with DM/PM had a 21% increase in endogenous thrombin potential (ETP), 36% higher peak thrombin concentration, and 11% faster thrombin generation, compared to controls (p â€‹< â€‹0.001, all, also after adjustment for potential confounders). Interestingly, although both diseases did not differ in thrombin generation potential, heterogenous variables predicted elevated ETPs in both of them. In DM, that was higher fibrinogen, C-reactive protein, and total cholesterol, whereas in PM, presence of arthritis and increased blood platelet count. Surprisingly, thrombin formation capacity remained in a robust inverse relationship with serum troponin (r â€‹= â€‹-0.67, p â€‹< â€‹0.001) in the patient group. CONCLUSIONS: DM/PM patients are characterized by an increased thrombin generation potential, suggesting prothrombotic plasma properties in both diseases. However, more studies are needed to verify its rationale and role in DM/PM clinical course and unfavorable clinical outcomes.

Hereditary thrombotic thrombocytopenic purpura and COVID-19: Impacts of vaccination and infection in this rare disease.

Introduction: Severe COVID-19 is associated with an important increase of von Willebrand factor and mild lowering of ADAMTS13 activity that may, in the presence of a strong inflammatory reaction, increase the risk of acute thrombotic thrombocytopenic purpura (TTP). Although acute episodes of immune-mediated TTP associated with COVID-19 or SARS-CoV-2 vaccination have been reported, data about clinical evolution of hereditary TTP (hTTP) during the pandemic are scarce. Method: We conducted a survey among adult patients of the International Hereditary TTP Registry about SARS-CoV-2 vaccination, COVID-19, and occurrence of acute hTTP episodes. Results: Of 122 adult hTTP patients invited to participate, 86 (70.5%) responded. Sixty-five had been vaccinated (75.6%), of which 14 had received in addition a booster, resulting in 139 individual vaccine shots. Although vaccinations in patients on plasma prophylaxis were done within 1 week of the last plasma infusion, all 23 patients treated with plasma on demand were vaccinated without prior plasma infusions. One patient on uninterrupted weekly plasma infusions presented within 3 days from his second vaccination with neurological symptoms and computed tomography scan 9 days later showed subacute ischemic/hemorrhagic frontal lobe infarction. A second male patient developed acute myocarditis after his second dose of mRNA-1273 vaccine. Twelve (14%) patients had COVID-19, associated with an acute hTTP episode in three of them: one patient had a transient ischemic attack, one a stroke, and a pregnant woman was hospitalized to intensify plasma treatment. Discussion: The risk of an acute episode triggered by COVID-19 seems higher than following vaccination in hTTP patients, who can be safely vaccinated against SARS-CoV-2.

Increased level of tumor necrosis factor-α in patients with antiphospholipid syndrome: marker not only of inflammation but also of the prothrombotic state.

Connections between inflammation and thrombosis are intriguing, especially in a condition such as an antiphospholipid syndrome (APS), a disease characterized by immune-mediated thrombosis. Tumor necrosis factor alpha (TNF-α) is a cytokine which shares proinflammatory and prothrombotic actions, while a soluble form of interlukin-2 receptor (sIL-2R) is considered a typical marker of (auto)immune inflammation with not known direct links to thrombosis. The differences in the pathogenesis of APS as compared to other autoimmune diseases might be connected with different serum levels of both mediators. To answer this question, we studied 147 patients with systemic lupus erythematosus (SLE), 21 with SLE-like syndrome (SLE-LS), 20 with isolated APS (primary antiphospholipid syndrome, PAPS), and 32 healthy controls. Thirty-six patients from the SLE group fulfilled the updated APS criteria (secondary APS, SAPS). In comparison to healthy subjects, TNF-α concentration was increased in all patients, while sIL-2R rose significantly in the SLE group only. APS (both SAPS and PAPS) was characterized by the highest levels of TNF-α. Moreover, patients with lupus anticoagulant or elevated levels of IgG anticardiolipin or IgG anti-ß(2)-glycoprotein I antibodies had higher TNF-α levels than patients without the presence of any type of antiphospholipid antibodies (aPL). In conclusion, the presence of aPL is associated with higher TNF-α level, whereas increased level of sIL-2R is rather connected with definite SLE where inflammatory processes prevail. It might be hypothesized that TNF-α plays a major role in pathogenesis of APS thrombotic phenomena.

Determinants of plasma fibrin clot lysis measured using three different assays in healthy subjects.

INTRODUCTION: Several methods for measuring fibrinolytic capacity in plasma have been developed yielding frequently inconsistent results. We investigated which factors determine fibrinolytic capacity in three plasma-based assays. MATERIAL AND METHODS: In 80 apparently healthy controls (aged 43 ± 10 years, 50 women [62.5%]) we evaluated fibrinolysis using three assays: (1) by Pieters et al. (CLT2018), (2) by Lisman et al. (CLT), and (3) by Carter et al. (Lys50). Coagulation factors and fibrinolytic proteins, including histidine-rich glycoprotein (HRG) and γ'-fibrinogen, were determined. Regression models were performed to identify determinants of lysis times. RESULTS: Positive correlations were observed between CLT2018 and both CLT (r = 0.73) and Lys50 (r = 0.61), as well as between CLT and Lys50 (r = 0.46, all p < 0.001). The main determinants of both CLT2018 and CLT were plasminogen activator inhibitor-1 (PAI-1), followed by thrombin-activatable fibrinolysis inhibitor (TAFI) and α2-antiplasmin. Histidine-rich glycoprotein was a predictor of the longest-normal CLT2018 alone (OR 1.04, 95% CI 1.02-1.06). α2-Antiplasmin and fibrinogen levels, followed by PAI-1 and TAFI determined Lys50. After adjustment for age, sex, and body mass index, C-reactive protein (CRP) was an independent predictor of the top quartiles of the three lysis times. CONCLUSIONS: We showed that apart from PAI-1, TAFI, and α2-antiplasmin, several other factors, in particular CRP, can affect the results of global fibrinolysis tests used in research. Our findings may help understand why the choice of a specific fibrinolysis assay can affect the presence and/or magnitude of intergroup differences in fibrinolytic capacity in a given disease state.

Chronic prothrombotic tendency in patients with granulomatosis with polyangiitis.

INTRODUCTION: Patients with granulomatosis with polyangiitis (GPA) show increased tendency toward thromboembolic phenomena in exacerbation of their disease. OBJECTIVES: The aim of the study was to evaluate thrombin generation potential and fibrinolytic plasma activity in patients with GPA, both in exacerbation and in remission. PATIENTS AND METHODS: We included 38 patients with GPA: 18 with exacerbated GPA and 20 in remission. The control group included 39 healthy participants matched for age and sex. Plasma thrombogenic potential was assessed using calibrated automated thrombography. Plasma fibrinolytic potential was assessed using clot lysis time (CLT). We also measured levels of inflammatory markers, thrombomodulin, and fibrinolysis proteins in all participants. RESULTS: In the whole group of patients with GPA, endogenous thrombin potential was higher by about 25% (P <0.001), while CLT was lower by about 20% (P = 0.02) when compared with controls. The endogenous thrombin potential was higher, the CLT lower, and the levels of thrombomodulin and inflammation markers (C­reactive protein, fibrinogen, factor VIII) higher both in patients with exacerbation and in remission than in the control group; no such differences were noted when comparing those with exacerbation and those in remission, however. The only parameter that differentiated patients with GPA exacerbation from those in remission was the D­dimer level (median [interquartile range], 1151 [597.2-2468.7] ng/ml vs 340.4 [255.1-500.7] ng/ml; P <0.001), a marker of lysis of intravascularly formed fibrin. CONCLUSIONS: Patients with GPA show an increased prothrombotic state, regardless of the disease phase. This is probably related to ongoing low-grade inflammation and endothelial injury. Large clinical studies are required to address the need for, and appropriate type of, antithrombotic prophylaxis during the course of GPA.