Blood Coagulation & Fibrinolysis最新文献

Disseminated intravascular coagulation (DIC) is a complex disorder characterized by widespread activation of blood clotting mechanisms throughout the body. Understanding the role of vascular endothelial glycocalyx in the pathogenesis and treatment of DIC is crucial for advancing our knowledge in this field. The vascular endothelial glycocalyx is a gel-like layer that coats the inner surface of blood vessels. It plays a significant role in maintaining vascular integrity, regulating fluid balance, and preventing excessive clotting. In the pathogenesis of DIC, the disruption of the vascular endothelial glycocalyx is a key factor. Pathological conditions trigger the activation of enzymes, including heparanase, hyaluronase, and matrix metalloproteinase. This activation leads to glycocalyx degradation, subsequently exposing endothelial cells to procoagulant stimuli. Additionally, the ANGPTs/Tie-2 signaling pathway plays a role in the imbalance between the synthesis and degradation of VEG, exacerbating endothelial dysfunction and DIC. Understanding the mechanisms behind glycocalyx degradation and its impact on DIC can provide valuable insights for the development of targeted therapies. Preservation of the glycocalyx integrity may help prevent the initiation and propagation of DIC. Strategies such as administration of exogenous glycocalyx components, anticoagulant agents, or Tie-2 antibody agents have shown promising results in experimental models. In conclusion, the vascular endothelial glycocalyx plays a crucial role in the pathogenesis and treatment of DIC. Further research in this field is warranted to unravel the complex interactions between the glycocalyx and DIC, ultimately leading to the development of novel therapies.

Determinants of thrombotic events remain uncertain in patients with atrial fibrillation treated with direct oral anticoagulants (DOACs). Our aim was to identify risk factors associated with thromboembolism in patients with at atrial fibrillation on DOACs and to construct and externally validate a predictive model that would provide a validated tool for clinical assessment of thromboembolism. In the development cohort, prediction model was built by logistic regression, the area under the curve (AUC), and Nomogram. External validation and calibration of the model using AUC and Hosmer-Lemeshow test. This national multicenter retrospective study included 3263 patients with atrial fibrillation treated with DOACs. The development cohort consisted of 2390 patients from three centers and the external validation cohort consisted of 873 patients from 13 centers. Multifactorial analysis showed that heavy drinking, hypertension, prior stroke/transient ischemic attack (TIA), cerebral infarction during hospitalization were independent risk factors for thromboembolism. The Alfalfa-TE risk score was constructed using these four factors (AUC = 0.84), and in the external validation cohort, the model showed good discriminatory power (AUC = 0.74) and good calibration (Hosmer-Lemeshow test P value of 0.649). Based on four factors, we derived and externally validated a predictive model for thromboembolism with DOACs in patients with atrial fibrillation (Alfalfa-TE risk score). The model has good predictive value and may be an effective tool to help reduce the occurrence of thromboembolism in patients with DOACs.

Introduction: Venous thromboembolism (VTE) remains a significant source of postinjury morbidity and mortality. Beta-hydroxy beta-methylglutaryl-CoA (HMG-CoA) reductase inhibitors (rosuvastatin) significantly reduced pathologic clotting events in healthy populations in a prior trial. Furthermore, acetylsalicylic acid (ASA) has been shown to be noninferior to prophylactic heparinoids for VTE prevention following orthopedic surgery. We hypothesized that a combination of rosuvastatin/ASA, in addition to standard VTE chemoprophylaxis, would reduce VTE in critically ill trauma patients.

Methods: This was a double-blind, placebo-controlled, randomized trial, evaluating VTE rates in two groups: ASA + statin (Experimental) and identical placebos (Control). Injured adults, 18-65 years old, admitted to the surgical intensive care unit without contraindications for VTE prophylaxis were eligible. Upon initiation of routine VTE chemoprophylaxis (i.e. heparin/heparin-derivatives), they were randomized to the Experimental or Control group. VTE was the primary outcome.

Results: Of 112 potentially eligible patients, 33% (n = 37, median new injury severity scale = 27) were successfully randomized, of whom 11% had VTEs. The Experimental group had no VTEs, while the Control group had 6 VTEs (4 PEs and 2 DVTs) in 4 (22%) patients (P = 0.046). The Experimental treatment was not associated with any serious adverse events. Due to the COVID-19 pandemic, the study was interrupted at the second interim analysis at <10% of the planned enrollment, with significance declared at P < 0.012 at that stage.

Discussion: The combination of ASA and rosuvastatin with standard VTE prophylaxis showed a favorable trend toward reducing VTEs with no serious adverse events. An appropriately powered phase III multicenter trial is needed to further investigate this therapeutic approach.

Level of evidence: Level II, Therapeutic.

The aim of this study was to define normal percentile values of coagulation parameters in preterm infants below 32 weeks of gestational age. This retrospective cohort study was conducted at Istanbul Medical Faculty. Preterm infants who were born prior to 32 weeks of gestation, between 2011 and 2021 were included and evaluated for coagulation parameters. Blood samples obtained through umbilical catheters prior to administration of heparinized flushes/fluids, vitamin K or fresh frozen plasma (FFP). Infants with a major bleeding disorder, intrapartum asphyxia or a history of familial bleeding disorders were excluded. Infants were grouped according to their gestational ages and birth weights: less than 24, 25-26, 27-28, 29-30, 31-32 weeks and <500, 500-749, 750-999, 1000-1249, 1250-1499, more than 1500 g. Third to 97th percentile values of both prothrombin time (PT) and activated partial thromboplastin time (aPTT) were defined. A total of 420 preterm infants were included. The median value and range of gestational age and birth weight of the infants were 29 (22.3-32.9) weeks and 1150 (395-2790) g, respectively. PT values were similar between subgroups according to gestational age but longer in infants with a birth weight less than 1000 g. aPTT values in infants born less than 24 weeks of gestation were found significantly longer. As maturation of the coagulation system increases by gestational age, very preterm infants (<32 gestational week (GW)) are under increased risk of bleeding. Determination of normal percentile distribution of coagulation parameters for preterm infants will shed light on the interpretation of coagulation parameters of these infants and minimize unnecessary FFP administrations.

Patients with sickle cell disease (SCD) are predisposed to a hypercoagulable state due to alterations in the coagulation system. Despite concern for the development of venous thromboembolism (VTE) in this population, there are no standardized guidelines for routine thromboprophylaxis. The objective of this study was to assess thromboprophylaxis practices of adult and pediatric treaters of SCD before and during the coronavirus disease of 2019 (COVID-19) pandemic. A cross-sectional electronic survey was distributed to pediatric and adult hematology oncology practitioners through seven SCD-specific interest groups between May 29, 2020, and July 13, 2020. Of 93 total responses, 14% ( N  = 13) reported they only treat patients more than 21 years old; 38.7% ( N  = 36) only treat patients 0-21 years old and 47.3% ( N  = 44) reported they treat both. Our study showed that before the COVID-19 pandemic, 96% of adult practitioners would recommend pharmacologic thromboprophylaxis, mechanical thromboprophylaxis or both for hospitalized adults with thromboprophylaxis, but only 76% of pediatric treaters would recommend any thromboprophylaxis in hospitalized children ( P  < 0.0001), with 24% of pediatric treaters choosing no thromboprophylaxis at all. During the COVID-19 pandemic, pharmacologic thromboprophylaxis specifically was recommended for adults by 94% of treaters and for pediatric patients by 76% of treaters. These findings suggest that despite the lack of evidence-based thromboprophylaxis guidelines in adults and children with thromboprophylaxis, subspecialty treaters routinely provide pharmacologic thromboprophylaxis in their adult patients and will modify their practice in pediatric patients who are considered at a high risk for VTE.

Objectives: We performed an analytical assessment of five coagulation tests [i.e. prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen, thrombin time (TT) and D-dimer] on the Roche Cobas t711 analyzer and a comparison study with the methodology in use at our laboratory (i.e. Werfen ACL Top 750 analyzer), expanding the analysis to the clinical implications of Cobas t711 implementation.

Methods: Imprecision studies were performed following the Clinical and Laboratory Standards Institute (CLSI) H57 A:2008 guideline. Linearity of D-dimer and fibrinogen tests was analysed according to the CLSI EP06-A: 2003 recommendations. For method comparison, the results were analyzed using the Bland-Altman plot and Passing-Bablok regression.

Results: Imprecision met manufacturer claims for PT, aPTT and TT. D-dimer and fibrinogen tests showed a coefficient of variation (CV)% over manufacturer claims at certain concentration levels. Linearity ranges could not be verified. Comparison study revealed that results are not interchangeable for any test, a lower correlation for aPTT test and lower D-dimer results from Roche Cobas t711.

Conclusion: The strength of this study relies on the analysis of the clinical implications of reporting Cobas t711 results compared to those obtained with the methodology in use at our laboratory. Different sensibility to factor deficiency, anticoagulant therapy and interferences might explain lower correlation rates obtained for the aPTT test. Different monoclonal antibodies used for D-dimer determination might explain the lower results obtained with the Cobas t711 analyzer. This aspect needs further studies given the relevance of D-dimer test to exclude thrombotic events and reinforces the need of harmonization in the haemostasis laboratory.

Glanzmann's Thrombasthenia (GT) is a rare hemorrhagic condition caused by a platelet surface receptor disorder of the glycoprotein (GP) IIb/IIIa. Symptoms of GT are various forms of hemorrhages, such as purpura, epistaxis and menorrhagia. Gastrointestinal bleeding (GIB) is a rare expression of the condition and may occur due to traumas in the GI tract or as a consequence of gastrointestinal angiodysplasia (GIADs). In this case report, we present a middle-aged woman with recurrent GIB consequent to GIADs with persistent melena and iron deficiency anemia. After several unsuccessful therapeutic interventions, the patient was studied by the hereditary hemorrhagic telangiectasia's (HHT - Osler-Weber-Rendu disease) unit, where she received bevacizumab, showing a complete improvement in symptoms as well as a reduction in her GIADs. This case shows that bevacizumab could be a possible line of treatment for patients with coagulation disorders with GIADs.

Aortic valve stenosis (AS) is the most common valvular disease, and surgical or transcatheter aortic valve replacement (TAVR) are the treatment options. Diminish in platelet production or dysfunction may occur due to shear stress, advanced age, and other coexisting diseases in AS patients. Bleeding is one of the complications of TAVR and associated with increased mortality. MPV (mean platelet volume) indicates platelet's thrombogenic activity. Overproduction or consumption of platelets in various cardiac conditions may affect MPV values. We aimed to investigate the pre and postprocedure MPV percentage change (MPV-PC) and its association with post-TAVR short-term complications. A total of 204 patients who underwent TAVR with a diagnosis of severe symptomatic AS were included. The mean age was 78.66 ± 6.45 years, and 49.5% of patients were women. Two groups generated according to composite end point (CEP) development: CEP(+) and CEP(-).110 patients(53.9%) formed CEP(+) group. Although baseline MPV and platelet levels were similar between groups, MPV was increased ( P  < 0.001) and platelet was decreased ( P  < 0.001) significantly following the procedure when compared to baseline. MPV-PC was significantly higher in the VARC type 2-4 bleeding ( P   =  0.036) and major vascular, access-related, or cardiac structural complication groups ( P   =  0.048) when CEP subgroups were analyzed individually. Regression analysis revealed that diabetes mellitus [ P   =  0.044, β: 1.806 odds ratio (95% confidence interval): 1.016-3.21] and MPV-PC [ P   =  0.007,β: 1.044 odds ratio (95% confidence interval): 1.012-1.077] as independent predictors of CEP development at 1 month after TAVR. The MPV increase following TAVR may be an indicator of adverse outcomes following TAVR procedure within 1-month.

Hemophilia and Von Willbrand disease (VWD) are the most well known types of hereditary hemorrhagic disorders (HHD). Hemophilia affects about 200 000 people worldwide, while VWD affects about 80 000. Because there is a scarcity of epidemiologic studies on hemophilia in Iraq, this study was carried out to evaluate the prevalence and incidence trends, as well as to identify some clinical and epidemiological features of hemophilia patients in Najaf province, Iraq. This study was carried out in the Najaf's hemophilia center. The data were obtained by reviewing all patients' documents, as well as the center registration book from 2011 to 2021. In addition, the Ministry of Health provided relevant population data for Najaf. Notably, there are currently 214 patients registered in Najaf province. The results revealed that the severe form of hemophilia A was the permanent type of HHDs in the patients compared with the rest of the types that include HHD with no significant difference Pat least 0.05. The frequency of this group of disorders appeared to increase in the period between 2011 and 2013, especially in 2012 followed by a decline in the incidence until 2021, which recorded a sudden increase in these disorders. These findings highlight that hemophilia types A and B were the most prevalent disorders of HHD in Najaf province, and the increase in number of newly recorded cases because of consanguineous marriage increased recently in this area.

Although the contribution of antiphospholipid antibodies (aPL) to thrombolembolism in systemic lupus erythematosus (SLE) is well known, there is not enough data on the contribution of various hereditary thrombophilic factors. In this study, we aimed to determine acquired and hereditary thrombophilic factors in adult patients with SLE. A total of 93 SLE patients (87 women and 6 men) were included. Data on clinical, demographic and laboratory characteristics, and disease activity scores (SLEDAI) of the patients were evaluated. The patients were analyzed with a screen, including lupus anticoagulant, anticardiolipin antibodies (aCL), antithrombin III, protein C, protein S, and homocysteine levels; factor V Leiden ( FVL ), methylenetetrahydrofolate reductase ( MTHFR ) and prothrombin G20210A gene mutations. A total of 23 thromboembolic events were reported in 17 (18.3%) of the patients. The frequency of pregnancy complications and SLEDAI scores were significantly higher in SLE patients who had a thromboembolism event ( P  < 0.05). Thromboembolism was detected in 12 (32.4%) of 37 patients with positive aPL antibody and 5 (8.9%) of 56 patients with negative aPL antibody ( P  = 0.006). In addition, thromboembolism developed in 11 (32.3%) of 34 lupus anticoagulant-positive patients and 6 (10.1%) of 59 lupus anticoagulant-negative patients ( P  = 0.012). Moreover, protein C levels were significantly lower in patients who developed thromboembolism ( P  < 0.05). Patients with and without thromboembolism were similar in terms of genetic thrombophilia factors ( MTHFR A1298C, MTHFR C677T, FVL and Prothrombin G20210A ) ( P  > 0.05). In conclusion, in the current study, some acquired (aPL, lupus anticoagulant and cCL IGG) and hereditary (protein C deficiency) thrombophilic factors were shown to be associated with the development of thrombosis in SLE patients. However, the effect of other hereditary factors on the development of thromboembolism could not be demonstrated. According to the data of this study, genetic screening seems inappropriate in terms of the risk of thromboembolism in patients with SLE.