Neutrophils as instigators of thrombosis: Beyond antimicrobial protection. / Neutrófilos como instigadores de trombosis: más allá de la protección antimicrobiana.

When activated, neutrophils release structures (NETs) composed of DNA, histones and granular proteins that provide an ideal matrix for platelet activation and coagulation mechanisms, thereby contributing to the pathogenesis of thrombosis in venous and arterial territories, as well as cancer-associated thrombosis. NETs play a key role in immunothrombosis, a term that describes the relationship between the immune response and coagulation.

Safety and effectiveness of a prothrombin complex concentrate in approved and off-label indications.

OBJECTIVE: To evaluate the effectiveness and safety of prothrombin complex concentrates (PCCs) in approved and off-label indications. BACKGROUND: PCCs are approved for the urgent reversal of vitamin K antagonists (VKAs). Data concerning the efficacy, safety and dosing for off-label indications are limited, but they are included in massive bleeding protocols. METHODS: This was a retrospective review of cases treated with four-factor PCCs (4F-PCCs) between January 2009 and 2016. Efficacy end-points include: (i) VKA reversal efficacy assessed by international normalised ratio (INR) normalisation (<1·5) and (ii) clinical efficacy as bleeding cessation and/or decreased number of transfused blood components and 24-h mortality in bleeding coagulopathy. The safety end-point is the incidence of thromboembolic events. RESULTS: A total of 328 patients were included (51·8% male, median age 78 years old). Indications were as follows: VKA reversal (66·6%), bleeding coagulopathy (30·5%) and direct anticoagulant (DOAC) reversal due to bleeding (2·5%). VKA reversal was effective in 97·1% of patients, and 76·5% demonstrated complete reversal (INR < 1·5); only 34·3% patients needed hemoderivatives. Prior to emergency procedures, PCCs achieved global responses in 83% of patients, with no bleeding complication during intervention. DOAC reversal was effective in 88·9% of patients. Bleeding cessation was associated with the dose administered (P = 0·002). In coagulopathy bleeding, haemorrhage cessation, established by the International Society of Thrombosis and Haemostais (ISTH) definition, occurred in 56·7% of massive bleeding events and in 42·5% of other coagulopathies; 24-h mortality was 30%, mainly related to active bleeding. Ten thrombotic episodes were observed (3·1%). CONCLUSION: 4F-PCC was effective as adjuvant treatment with an acceptable safety profile, not only for the emergent reversal of VKAs but also for refractory coagulopathy associated with major bleeding.

Implementation of a management protocol for massive bleeding reduces mortality in non-trauma patients: Results from a single centre audit.

OBJECTIVE: To audit the impact upon mortality of a massive bleeding management protocol (MBP) implemented in our center since 2007. DESIGN: A retrospective, single-center study was carried out. Patients transfused after MBP implementation (2007-2012, Group 2) were compared with a historical cohort (2005-2006, Group 1). BACKGROUND: Massive bleeding is associated to high mortality rates. Available MBPs are designed for trauma patients, whereas specific recommendations in the medical/surgical settings are scarce. PATIENTS: After excluding patients who died shortly (<6h) after MBP activation (n=20), a total of 304 were included in the data analysis (68% males, 87% surgical). INTERVENTIONS: Our MBP featured goal-directed transfusion with early use of adjuvant hemostatic medications. VARIABLES OF INTEREST: Primary endpoints were 24-h and 30-day mortality. Fresh frozen plasma-to-red blood cells (FFP:RBC) and platelet-to-RBC (PLT:RBC) transfusion ratios, time to first FFP unit and the proactive MBP triggering rate were secondary endpoints. RESULTS: After MBP implementation (Group 2; n=222), RBC use remained stable, whereas FFP and hemostatic agents increased, when compared with Group 1 (n=82). Increased FFP:RBC ratio (p=0.053) and earlier administration of FFP (p=0.001) were also observed, especially with proactive MBP triggering. Group 2 patients presented lower rates of 24-h (0.5% vs. 7.3%; p=0.002) and 30-day mortality (15.9% vs. 30.2%; p=0.018) - the greatest reduction corresponding to non-surgical patients. Logistic regression showed an independent protective effect of MBP implementation upon 30-day mortality (OR=0.3; 95% CI 0.15-0.61). CONCLUSIONS: These data suggest that the implementation of a goal-directed MBP for prompt and aggressive management of non-trauma, massive bleeding patients is associated to reduced 24-h and 30-day mortality rates.

Multidisciplinary consensus document on the management of massive haemorrhage (HEMOMAS document).

Massive haemorrhage is common and often associated with high morbidity and mortality. We perform a systematic review of the literature, with extraction of the recommendations from the existing evidences because of the need for its improvement and the management standardization. From the results we found, we wrote a multidisciplinary consensus document. We begin with the agreement in the definitions of massive haemorrhage and massive transfusion, and we do structured recommendations on their general management (clinical assessment of bleeding, hypothermia management, fluid therapy, hypotensive resuscitation and damage control surgery), blood volume monitoring, blood products transfusion (red blood cells, fresh frozen plasma, platelets and their best transfusion ratio), and administration of hemostatic components (prothrombin complex, fibrinogen, factor VIIa, antifibrinolytic agents).

[The 2013 Seville Consensus Document on alternatives to allogenic blood transfusion. An update on the Seville Document]. / 2013. Documento Sevilla de Consenso sobre Alternativas a la Transfusión de Sangre Alogénica. Actualización del Documento Sevilla.

Since allogeneic blood transfusion (ABT) is not harmless, multiple alternatives to ABT (AABT) have emerged, though there is great variability in their indications and appropriate use. This variability results from the interaction of a number of factors, including the specialty of the physician, knowledge and preferences, the degree of anemia, transfusion policy, and AABT availability. Since AABTs are not harmless and may not meet cost-effectiveness criteria, such variability is unacceptable. The Spanish Societies of Anesthesiology (SEDAR), Hematology and Hemotherapy (SEHH), Hospital Pharmacy (SEFH), Critical Care Medicine (SEMICYUC), Thrombosis and Hemostasis (SETH) and Blood Transfusion (SETS) have developed a Consensus Document for the proper use of AABTs. A panel of experts convened by these 6 Societies have conducted a systematic review of the medical literature and have developed the 2013 Seville Consensus Document on Alternatives to Allogeneic Blood Transfusion, which only considers those AABT aimed at decreasing the transfusion of packed red cells. AABTs are defined as any pharmacological or non-pharmacological measure aimed at decreasing the transfusion of red blood cell concentrates, while preserving patient safety. For each AABT, the main question formulated, positively or negatively, is: « Does this particular AABT reduce the transfusion rate or not?¼ All the recommendations on the use of AABTs were formulated according to the Grades of Recommendation Assessment, Development and Evaluation (GRADE) methodology.

Matrix metalloproteinase-10 effectively reduces infarct size in experimental stroke by enhancing fibrinolysis via a thrombin-activatable fibrinolysis inhibitor-mediated mechanism.

BACKGROUND: The fibrinolytic and matrix metalloproteinase (MMP) systems cooperate in thrombus dissolution and extracellular matrix proteolysis. The plasminogen/plasmin system activates MMPs, and some MMPs have been involved in the dissolution of fibrin by targeting fibrin(ogen) directly or by collaborating with plasmin. MMP-10 has been implicated in inflammatory/thrombotic processes and vascular integrity, but whether MMP-10 could have a profibrinolytic effect and represent a promising thrombolytic agent is unknown. METHODS AND RESULTS: The effect of MMP-10 on fibrinolysis was studied in vitro and in vivo, in MMP-10-null mice (Mmp10(-/-)), with the use of 2 different murine models of arterial thrombosis: laser-induced carotid injury and ischemic stroke. In vitro, we showed that MMP-10 was capable of enhancing tissue plasminogen activator-induced fibrinolysis via a thrombin-activatable fibrinolysis inhibitor inactivation-mediated mechanism. In vivo, delayed fibrinolysis observed after photochemical carotid injury in Mmp10(-/-) mice was reversed by active recombinant human MMP-10. In a thrombin-induced stroke model, the reperfusion and the infarct size in sham or tissue plasminogen activator-treated animals were severely impaired in Mmp10(-/-) mice. In this model, administration of active MMP-10 to wild-type animals significantly reduced blood reperfusion time and infarct size to the same extent as tissue plasminogen activator and was associated with shorter bleeding time and no intracranial hemorrhage. This effect was not observed in thrombin-activatable fibrinolysis inhibitor-deficient mice, suggesting thrombin-activatable fibrinolysis inhibitor inactivation as one of the mechanisms involved in the MMP-10 profibrinolytic effect. CONCLUSIONS: A novel profibrinolytic role for MMP-10 in experimental ischemic stroke is described, opening new pathways for innovative fibrinolytic strategies in arterial thrombosis.

Effects of thermal annealing on the structural and optical properties of carbon-implanted SiO2.

Amorphous carbon (a-C) nanoclusters were synthesized by the implantation of carbon ions (C-) into thermally grown silicon dioxide film (-500 nm thick) on a Si (100) wafer and processed by high temperature thermal annealing. The carbon ions were implanted with an energy of 70 keV at a fluence of 5 x 10(17) atoms/cm2. The implanted samples were annealed at 1100 degrees C for different time periods in a gas mixture of 96% Ar+4% H2. Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and High Resolution Transmission Electron Microscopy (HRTEM) were used to study the structural properties of both the as-implanted and annealed samples. HRTEM reveals the formation of nanostructures in the annealed samples. The Raman spectroscopy also confirms the formation of carbon nano-clusters in the samples annealed for 10 min, 30 min, 60 min and 90 min. No Raman features originating from the carbon-clusters are observed for the sample annealed further to 120 min, indicating a complete loss of implanted carbon from the SiO2 layer. The loss of the implanted carbon in the 120 min annealed sample from the SiO2 layer was also observed in the XPS depth profile measurements. Room temperature photoluminescence (PL) spectroscopy revealed visible emissions from the samples pointing to carbon ion induced defects as the origin of a broad 2.0-2.4 eV band, and the intrinsic defects in SiO2 as the possible origin of the -2.9 eV bands. In low temperature photoluminescence spectra, two sharp and intense photoluminescence lines at -3.31 eV and -3.34 eV appear for the samples annealed for 90 min and 120 min, whereas no such bands are observed in the samples annealed for 10 min, 30 min, and 60 min. The Si nano-clusters forming at the Si-SiO2 interface could be the origin of these intense peaks.

Impact of the mutation profile on thrombotic risk in cancer patients.

Patients with cancer present with an elevated risk of thrombosis, which entails high morbidity and mortality. Various predictive scales that incorporate clinical and biological data have been developed to identify those at high risk of thrombosis, but, in general, they do not allow for the optimal selection of subjects who are candidates for thromboprophylaxis. Recent studies have demonstrated that the mutation profile has a high impact on the risk of thrombosis; this will facilitate developing new predictive models of thrombosis in patients with cancer.

SEA 2022 Standards for Global Control of Cardiovascular Risk. / Estándares SEA 2022 para el control global del riesgo cardiovascular.

One of the objectives of the Spanish Society of Arteriosclerosis is to contribute to better knowledge of vascular disease, its prevention and treatment. It is well known that cardiovascular diseases are the leading cause of death in our country and entail a high degree of disability and health care costs. Arteriosclerosis is a multifactorial disease and therefore its prevention requires a global approach that takes into account the different risk factors with which it is associated. Therefore, this document summarizes the current level of knowledge and includes recommendations and procedures to be followed in patients with established cardiovascular disease or at high vascular risk. Specifically, this document reviews the main symptoms and signs to be evaluated during the clinical visit, the laboratory and imaging procedures to be routinely requested or requested for those in special situations. It also includes vascular risk estimation, the diagnostic criteria of the different entities that are cardiovascular risk factors, and makes general and specific recommendations for the treatment of the different cardiovascular risk factors and their final objectives. Finally, the document includes aspects that are not usually referenced in the literature, such as the organization of a vascular risk consultation.

Angiogenic and prothrombotic markers in extensive slow-flow vascular malformations: implications for antiangiogenic/antithrombotic strategies.

BACKGROUND: Venous and combined malformations are slow-flow haemodynamically inactive lesions that are present at birth and worsen slowly with advancing age, showing no tendency towards involution. The pathogenesis of vascular anomalies has not been fully elucidated, but their formation and progression are closely related to angiogenesis. Localized intravascular coagulation associated with venous or combined malformations is characterized by low fibrinogen, high D-dimers, and normal platelet count. OBJECTIVES: To assess the relationship of angiogenic factors with prothrombotic and endothelial damage/dysfunction markers in patients with extensive slow-flow vascular malformations. METHODS: A 2-year study (2005-2007) included 31 consecutive patients with extensive slow-flow vascular malformations from one centre. RESULTS: Serum levels of the endothelial receptor tyrosine kinase TIE-2, matrix metalloproteinase (MMP)-9 and angiopoietin (Ang)-2 and plasma levels of D-dimer, plasminogen activator inhibitor type 1 (PAI-1), tissue-type plasminogen activator and von Willebrand factor (vWf) were significantly increased in patients compared with healthy controls, whereas serum levels of vascular endothelial growth factor (VEGF)-C, VEGF-D, MMP-2, Ang-1, platelet-derived growth factor (PDGF)-AB and PDGF-BB were significantly decreased in patients compared with controls. A strong positive correlation was present between Ang-1 and PDGF-AB levels (r = 0.63, P < 0.001), between PDGF-AB and PDGF-BB levels (r = 0.67, P < 0.001), and between fibrinogen and PAI-1 levels (r = 0.41, P = 0.031). A strong negative correlation was present between Ang-1 and vWf levels (r = -0.48, P = 0.006), between D-dimer and fibrinogen levels (r = -0.71, P < 0.001), and between PDGF-AB and vWf levels (r = -0.42, P = 0.017). CONCLUSIONS: These findings suggest that angiogenic, coagulation and endothelial damage/dysfunction markers are possibly linked in pathogenesis of extensive slow-flow vascular malformations, and might have therapeutic implications.

[Coagulopathy and thrombosis: similarities and differences among pathogenic coronaviruses].

One of the most significant negative prognostic factors in patients suffering from the disease caused by SARS-CoV-2 (COVID-19) is the development of coagulopathy, associated with abnormal laboratory findings, such as increased D-dimer, and venous thromboembolic complications, requiring thromboprophylactic strategies. The main clinical characteristics of COVID-19 patients are revised here as compared to other coronavirus infections, such as Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS), emphasizing clinical, diagnostic and therapeutic aspects.

Stromelysin-2 (MMP-10) deficiency does not affect adipose tissue formation in a mouse model of nutritionally induced obesity.

Adipose tissue development is associated with angiogenesis, adipogenesis and extracellular matrix degradation. The class of matrix metalloproteinases contributes to these processes, but little information is available on the role of individual proteinases. We report that stromelysin-2 (MMP-10) deficiency has no significant effect on total body weight or on subcutaneous (SC) or gonadal (GON) adipose tissue mass of mice kept on a high fat diet for 15 weeks. The adipocyte size and density in SC and GON adipose tissues were also comparable in MMP-10 deficient and wild-type control mice. Similarly, blood vessel size and density in obese SC and GON adipose tissues was not affected by MMP-10 deficiency. Metabolic parameters and blood cell composition were similar for both genotypes. Stromelysin-1 (MMP-3) expression was significantly reduced in adipose tissues of the deficient mice as compared to the wild-type controls. These data indicate that MMP-10 does not significantly contribute to adipose tissue development and associated angiogenesis in a mouse model of nutritionally induced obesity.

Tissue-specific PAI-1 gene expression and glycosylation pattern in insulin-resistant old rats.

Increased levels of plasminogen activator inhibitor-1 (PAI-1) have been associated with obesity, aging, insulin resistance, and type 2 diabetes, conditions that contribute to increased cardiovascular risk. PAI-1 is expressed in a variety of tissues, but the cellular origin of plasma PAI-1 is unknown. To link insulin resistance, aging, and cardiovascular disease, we examined the expression and glycosylation pattern of PAI-1 in liver and white adipose tissue (WAT) from adult (3 mo) and insulin-resistant old (24 mo) Wistar rats. Glycosylated PAI-1 protein was also purified by affinity chromatography from endothelial culture supernatans to analyze its inhibitory activity. We also analyzed the contribution of adipocytes and stromal vascular cells from WAT to PAI-1 levels with aging. Aging caused a significant increase of PAI-1 mRNA (P < 0.001) in WAT that was predominantly due to the adipocytes and not to stroma-vascular cells, while there was no modification in liver from aged rats. Moreover, PAI-1 expression increased during preadipocyte differentiation (P < 0.001). Furthermore, we found a tissue-dependent PAI-1 glycosylation pattern: adipose tissue only expresses the glycosylated PAI-1 form, whereas the liver mainly expresses the nonglycosylated form. Finally, we also found evidences suggesting that the glycosylated PAI-1 form shows higher inhibitory activity than the nonglycosylated. Our data suggest that WAT may be a major source of the elevated plasma levels of PAI-1 in insulin-resistant old rats. Additionally, the high degree of PAI-1 glycosylation and activity, together with the significant increase in visceral fat in old rats, may well contribute to an increased cardiovascular risk associated with insulin-resistant states.

Improvement of appropriate pharmacological prophylaxis in hospitalised cancer patients with a multiscreen e-alert system: a single-centre experience.

PURPOSE: Thromboprophylaxis use among medical inpatients, including cancer patients, is suboptimal. We aimed to evaluate the impact of a novel multiscreen version (v2.0) of an e-alert system for VTE prevention in hospitalised cancer medical patients compared to the original software. METHODS: Prospective study including 989 consecutive adult cancer patients with high-risk of VTE. Patients were followed-up 30 days post-discharge. Two periods were defined, according to the operative software. RESULTS: E-alert v2.0 was associated with an increase in the use of LMWH prophylaxis (65.5% vs. 72.0%); risk difference (95% CI) 0.064 (0.0043-0.12). Only 16% of patients in whom LMWH prophylaxis was not prescribed lacked a contraindication. No significant differences in the rates of VTE (2.9% vs. 3.2%) and major bleeding (2.7% vs. 4.0%) were observed. CONCLUSIONS: E-alert v2.0 further increased the use of appropriate thromboprophylaxis in hospitalised cancer patients, although was not associated with a reduction in VTE incidence.

Generation in plasma of a fast-acting inhibitor of plasminogen activator in response to endotoxin stimulation.

Endotoxin producing bacteria cause disseminated intravascular coagulation (DIC); however, the mechanism of endotoxin action in man is still unclear. Impairment of the fibrinolytic system has been suggested as a contributing mechanism. A single injection of Escherichia coli lipopolysaccharide in rabbits resulted in a marked and prolonged increase of the levels of a fast-acting inhibitor of plasminogen activator (PA-inhibitor) in plasma (from 3.9 +/- 0.7 to 41 +/- 13.2 U/ml after 3 h). Gel filtration studies indicated that inhibition of human tissue-type plasminogen activator (t-PA) by rabbit plasma is accompanied by a change in the elution profile of the activator compatible with the formation of an enzyme-inhibitor complex with an apparent molecular weight of 100,000. Injection of human t-PA (1,500 IU/kg body wt) in endotoxin treated animals resulted in very fast inhibition of t-PA and formation of a similar complex. The half-life of circulating PA-inhibitor activity in rabbits was about 7 min as estimated by donor receiver plasma transfusion experiments. Stimulation of cultured human endothelial cells with endotoxin resulted in enhanced rate of accumulation of PA-inhibitor activity in the culture medium (two- to sevenfold increase). In five patients with septicemia, markedly increased levels of PA-inhibitor (14.3 +/- 15.5 U/ml) as compared with control subjects (1.3 +/- 0.7 U/ml) were observed in plasma. A very strong correlation (r = 0.98) was found between inhibition of t-PA and of urokinase in all conditions, suggesting that this fast-acting inhibitor reacts with both plasminogen activators. These data suggest that the appearance of this fast-acting PA-inhibitor is very sensitive to endotoxin stimulation. The marked increase in the level of PA-inhibitor in blood may contribute to the pathogenesis of DIC in septicemia.

Influence of the fast-acting inhibitor of plasminogen activator on in vivo thrombolysis induced by tissue-type plasminogen activator in rabbits. Interference of tissue-derived components.

The influence of endotoxin-induced elevated plasma levels of the fast-acting inhibitor of plasminogen activator (PA-inhibitor) on thrombolysis was investigated in rabbits with a jugular vein thrombus. Infusion of human tissue-type plasminogen activator (t-PA) produced similar degrees of thrombolysis in control and endotoxin-treated rabbits, although no free t-PA could be demonstrated in plasma of endotoxin-treated animals. Infusion of t-PA in an extracorporeal arteriovenous shunt resulted in loss of thrombolytic activity in endotoxin-treated animals but not in control animals. Blood clots superfused in vitro with mixtures of t-PA and normal plasma lysed in contrast to clots superfused with t-PA and PA-inhibitor-rich plasma. However, addition of rabbit lung slices to the plasma surrounding the blood clot, reversed the inhibition of thrombolysis by PA-inhibitor-rich plasma. This indicates that tissue-derived factor(s) are involved in the regulation of in vivo thrombolysis. These hypothetical factor(s) are, however, very unstable in plasma, which has thus far precluded their further characterization.

Independent association of matrix metalloproteinase-10, cardiovascular risk factors and subclinical atherosclerosis.

OBJECTIVES: Circulating levels of matrix metalloproteinase (MMP)-10 are related to inflammation in asymptomatic subjects with cardiovascular risk factors. Whether MMP-10 is associated with the severity of atherosclerosis remains to be determined. This study examines the relationship of systemic MMP-10 levels with atherosclerotic risk factors and subclinical atherosclerosis. METHODS AND RESULTS: Circulating levels of MMP-1, -9 and -10, and markers of inflammation [fibrinogen, interleukin-6, von Willebrand factor, and high-sensitivity C-reactive protein (hs-CRP)] were measured in 400 subjects (mean age 54.3 years, 77.7% men) with cardiovascular risk factors but free from clinical cardiovascular disease. Subclinical atherosclerosis was evaluated by both the mean carotid intima-media thickness (IMT) and the presence of atherosclerotic plaques with the use of B-mode ultrasound in all subjects. MMP-10 levels were positively correlated with fibrinogen (r = 0.24, P < 0.001), hs-CRP (r = 0.14, P < 0.01) and carotid IMT (r = 0.17, P < 0.01). The association between MMP-10 and IMT remained significant in multiple regression analysis (P < 0.02) when controlling for traditional atherosclerotic risk factors and inflammatory markers. Such an association was not observed for MMP-1 and -9. Subjects in the highest MMP-10 tertile had significantly higher carotid IMT (adjusted odds ratio 6.3, 95% confidence interval 1.3-31.4, P = 0.024). In addition, MMP-10 levels were significantly higher in patients with carotid plaques (n = 78) than in those with no plaques after adjusting for age and sex (P < 0.01). CONCLUSION: Higher serum MMP-10 levels were associated with inflammatory markers, increased carotid IMT and atherosclerotic plaques in asymptomatic subjects. Circulating MMP-10 may be useful to identify subclinical atherosclerosis in subjects free from cardiovascular disease.

[Treatment of antiphospholipid syndrome]. / Tratamiento del síndrome antifosfolípido.

The antiphospholipid syndrome (APS) is a disorder of recurrent thrombosis and/or pregnancy loss associated with the presence of antiphospholipid antibodies and persistently positive lupus anticoagulant, anticardiolipin or anti beta2-glycoprotein1. Oral anticoagulants are the best available and most effective treatment for the secondary prevention of recurrent venous or arterial thrombosis. Patients with APS are treated with long-term therapy to prolong the INR to 2.0-3.0. Low-molecular-weight heparin in combination with low-aspirin dose is a reasonable strategy to avoid pregnancy loss in women with this syndrome.