Multidisciplinary Consensus for the Management of Pulmonary Thromboembolism. / Consenso multidisciplinar para el manejo de la tromboembolia de pulmón.

We have updated recommendations on 12 controversial topics that were published in the 2013 National Consensus on the diagnosis, risk stratification and treatment of patients with pulmonary embolism (PE). A comprehensive review of the literature was performed for each topic, and each recommendation was evaluated in two teleconferences. For diagnosis, we recommend against using the Pulmonary Embolism Rule Out Criteria (PERC) rule as the only test to rule out PE, and we recommend using a D-dimer cutoff adjusted to age to rule out PE. We suggest using computed tomography pulmonary angiogram as the imaging test of choice for the majority of patients with suspected PE. We recommend using direct oral anticoagulants (over vitamin K antagonists) for the vast majority of patients with acute PE, and we suggest using anticoagulation for patients with isolated subsegmental PE. We recommend against inserting an inferior cava filter for the majority of patients with PE, and we recommend using full-dose systemic thrombolytic therapy for PE patients requiring reperfusion. The decision to stop anticoagulants at 3 months or to treat indefinitely mainly depends on the presence (or absence) and type of risk factor for venous thromboembolism, and we recommend against thrombophilia testing to decide duration of anticoagulation. Finally, we suggest against extensive screening for occult cancer in patients with PE.

Cancer-Associated Thrombosis: Beyond Clinical Practice Guidelines-A Multidisciplinary (SEMI-SEOM-SETH) Expert Consensus.

Despite the growing interest and improved knowledge about venous thromboembolism in cancer patients in the last years, there are still many unsolved issues. Due to the limitations of the available literature, evidence-based clinical practice guidelines are not able to give solid recommendations for challenging scenarios often present in the setting of cancer-associated thrombosis (CAT). A multidisciplinary expert panel from three scientific societies-Spanish Society of Internal Medicine (SEMI), Spanish Society of Medical Oncology (SEOM), and Spanish Society Thrombosis and Haemostasis (SETH)-agreed on 12 controversial questions regarding prevention and management of CAT, which were thoroughly reviewed to provide further guidance. The suggestions presented herein may facilitate clinical decisions in specific complex circumstances, until these can be made leaning on reliable scientific evidence.

Rivaroxaban in the treatment of venous thromboembolism and the prevention of recurrences: a practical approach.

Anticoagulation therapy is the standard treatment of patients with symptomatic venous thromboembolism (VTE), including deep vein thrombosis and pulmonary embolism. Until recently, treatment of VTE was based on parenteral or low-molecular-weight heparin for initial therapy (5-10 days) and oral vitamin K antagonists for long-term therapy. Those treatments have some limitations, including parenteral administration (heparins), the need for frequent monitoring and dose adjustments, interactions with several medications, and dietary restrictions (vitamin K antagonists). Rivaroxaban is a new oral direct factor Xa inhibitor with a wide therapeutic window, predictable anticoagulant effect, no food interactions, and few drug interactions. Consequently, no periodic monitoring of anticoagulation is needed, and fixed doses can be prescribed. EINSTEIN program demonstrated that rivaroxaban was as effective as and significantly safer than standard therapy for treatment of VTE. Rivaroxaban was recently authorized so doubts exist about how to use it in daily clinical practice. This document aims to clarify common questions formulated by clinicians regarding the use of this new drug.

Functional characterization of twelve natural PROS1 mutations associated with anticoagulant protein S deficiency.

BACKGROUND: The molecular mechanisms by which PROS1 mutations result in protein S deficiency are still unknown for many of the mutations, particularly for those that result in a premature termination codon. The aim of this study was to analyze the functional relevance on mRNA and protein expression of 12 natural PROS1 mutations associated with protein S deficiency. DESIGN AND METHODS: Five mutations were nonsense, three were small frameshift deletions, one was c.258,259AG>GT at the 3' end of exon 3, one was p.M640T and the last two were c.-7C>G and p.L15H, found in double heterozygosis as [c.-7C>G;44T>A]. The apparently neutral variant p.R233K was also analyzed. PROS1 cDNA was assessed by reverse transcriptase polymerase chain reaction of platelet mRNA. Expression of mutant proteins was determined by site-directed mutagenesis and analyses of transiently transfected PROS1 mutants in COS-7 cells. RESULTS: Only cDNA from the normal allele was observed from the five nonsense mutations, the frameshift deletion c.1731delT and from c.258,259AG>GT. Both the normal and the mutated alleles were observed from [c.-7C>G;44T>A], c.187,188delTG and p.M640T. Transient expression analyses of PROS1 mutants whose mRNA was normally expressed revealed greatly reduced secretion of p.L15H and c.1272delA, mild secretion values of p.M640T and normal secretion levels of c.-7C>G and, as expected, p.R233K. CONCLUSIONS: Whereas the main cause of quantitative protein S deficiency associated with missense mutations is defective synthesis, stability or secretion of the mutated protein, the main mechanism for the deficiency associated with mutations that generate a premature termination codon is not the synthesis of a truncated protein, but the exclusion of the mutated allele, probably by nonsense-mediated mRNA decay.

Elevation of E-selectin concentrations may correlate with potential endothelial dysfunction in individuals with hypopituitarism during therapy with growth hormone.

Increased mortality due to cardiovascular disease has been described in adult patients with untreated growth hormone (GH) deficiency. GH replacement therapy has been demonstrate to improve vascular reactivity and reverses early atherosclerotic changes in GH deficient adults. The objective of this study was the assessment of fibrinolytic markers, soluble adhesion molecules, inflammatory cytokines and endothelial function in hypopituitary adults with GH deficiency and with GH replacement therapy. We studied 20 GH deficient patients, 10 men and 10 women (aged, 43.4 +/- 8.4 years) under GH replacement therapy compared with a control group matched for age and body mass index, 9 men and 16 women. All subjects, patients and controls, were life-long non-smokers, normotensive and non-diabetic. The following variables were recorded: anthropometrical and body composition variables, serum concentrations of glucose, insulin and C-peptide; thrombin anti-thrombin fragments and fibrin degradation product D-dimer that were determined by an enzyme-linked-immunosorbent assay (ELISA); IGF-I by radioimmunoassay; C-reactive protein by highly sensitive immunonephelometry; E-selectine, P-selectine, soluble intercellular cell adhesion molecule-1, soluble vascular cell adhesion molecule-1, interleukin-6 and monocyte chemoattractant protein-1 by ELISA. The assessment of endothelial function in vivo was measured by Doppler. Patients with GH deficiency had higher hip/waist ratio and C-peptide and triglycerides concentrations than controls. Our results demonstrated no difference in fibrinolytic markers among patients and controls. E-selectin concentrations were higher in patients than in controls, 22.5+/-11.4 vs. 10.7+/-6.2 microg/L, p = 0.0001. P-selectin, soluble intercellular cell adhesion molecule-1, soluble vascular cell adhesion molecule-1, interleukin-6, monocyte chemoattractant protein-1 and C-reactive protein were similar in the 2 groups. Vascular reactivity and carotid intima-media thickness were also similar in patients and controls. In this study we have demonstrated in adults with GH deficiency under GH substitution elevation of E-selectin concentrations that may correlate with potential endothelial dysfunction suggesting that the protective effect of GH in these patients may be enhancing other mechanisms.

D-dimer local expression is increased in symptomatic patients undergoing carotid endarterectomy.

BACKGROUND: Although atherosclerosis is a silent widespread disease, the focal character of the lesions triggering the clinical manifestations is unquestionable. We hypothesized that symptomatic patients with advanced, unstable carotid plaques have increased local intraplaque and circulating levels of fibrin-fibrinogen related products. METHODS: Plaque tissue and plasma samples were studied in 106 patients undergoing endarterectomy for symptomatic and asymptomatic carotid disease. Fibrin-fibrinogen related products were evaluated by ELISA, Western-blotting, and histology. All tested parameters were compared with patient carotid symptomatology, multiple vascular risk factors (VRF), bilateral carotid pathology, ultrasound examination, and previous therapies with statins and/or antiplatelet drugs. RESULTS: In symptomatic patients, plasma D-dimer was elevated in patients with unstable carotid plaques (UNS) compared with stable (STA) ones (857+/-121 vs. 692+/-156 ng/ml, p=0. 026). Furthermore, plasma D-dimer was significantly increased in patients with a coexistence of carotid and coronary artery disease, compared to others (976+/-325 vs. 714+/-197 ng/ml; p<0.001). Intra-plaque D-dimer content was increased in ulcerated-complicated (UC) plaques compared with fibrous non-complicated (F) plaques in symptomatic patients (5.9+/-1 vs. 1.8+/-1, p<0.001), and in patients with hypercholesterolaemia, compared with those with normal cholesterol levels (6.1+/-1 vs. 2.9+/-0.7; p=0.027). However, there was no correlation between D-dimer content in the carotid plaque and plasma D-dimer levels. CONCLUSIONS: Hypercholesterolemia and UC plaques appear to be associated with high fibrin intraplaque turnover as demonstrated by higher intraplaque D-dimer. Plasma markers of fibrin turnover were increased in UNS plaques, and in patients with coexisting carotid and coronary artery disease. Although, both plasma and plaque D-dimers were associated with unstable carotid disease, the usefulness of the measurement of plasma D-dimer in these patients should be confirmed by prospective studies.

Hemostatic status in long-term surviving xenografts.

BACKGROUND: Liver xenotransplantation presents, apart from immunologic problems, metabolic incompatibilities between species. The liver plays a key role in blood coagulation. The aim of this study is to describe the hemostatic status of long-term surviving xenografts in a hamster-to-rat liver xenotransplantation model. METHODS: Orthotopic liver transplantation with Tacrolimus and MMF was carried out with Golden Syrian hamsters, Brown Norway, or Dark Agouti rats as donors and Lewis rats as recipients. Prothrombine time (PT), activated partial thromboplastin time (APTT), antithrombin, protein-C, free protein-S, TAT-complexes, and factors V and VIII were assessed using standard methods. RESULTS: Protein-C was absent in rats, but values in xenotransplanted animals increased progressively toward those recorded in hamsters. Xenotransplanted animals also acquired PT, APTT, free protein-S, and antithrombin levels similar to those of donors and we observed a substantial activation of coagulation especially 7 days post-transplantation. Despite TAT high levels, we did not find thrombotic alterations in the histologic analysis of grafts. CONCLUSIONS: These results reflect a destabilization of the thrombotic-hemostatic balance, not associated with consumption coagulopathy, which gradually disappears. This deregulation is a general imbalance resulting from the replacement of all the components of hepatic synthesis. After 100 days of xenotransplantation, the absence of symptoms of thrombosis or hemorrhage suggests that the change of hemostatic status takes place under conditions of relative equilibrium.

Peripheral fibrinolytic markers, soluble adhesion molecules, inflammatory cytokines and endothelial function in hypopituitary adults with growth hormone deficiency.

BACKGROUND: Increased mortality due to cardiovascular disease has been described in adult patients with untreated GH deficiency (GHD). GH replacement has been demonstrate to improve vascular reactivity and reverse early atherosclerotic changes in adults with GHD. OBJECTIVE: Assessment of fibrinolytic markers, soluble adhesion molecules, inflammatory cytokines and endothelial function in hypopituitary adults with GHD at baseline and 1 year after GH replacement therapy. METHODS: We studied 10 patients with GHD (five men and five women; aged 45.6 +/- 10.4 years) at baseline and 1 year after GH replacement therapy compared with a control group (nine men and 16 women) matched for age and body mass index (BMI). All subjects, patients and controls, were life-long nonsmokers, normotensive and nondiabetic. The following variables were recorded: anthropometric and body composition variables, serum concentrations of glucose, insulin and C-peptide; thrombin anti-thrombin (TAT) fragments and fibrin degradation product D-dimer, which were determined by an enzyme-linked immunosorbent assay (ELISA); IGF-I by radioimmunoassay (RIA); C-reactive protein (CRP) by highly sensitive immunonephelometry; E-selectin, P-selectin, soluble intercellular cell adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), interleukin-6 (IL-6) and monocyte chemoattractant protein-1 (MCP-1) by ELISA. The assessment of endothelial function in vivo was measured with a Doppler device. RESULTS: Patients with GHD without GH substitution had higher hip/waist ratio and body fat than controls. Insulin, C-peptide and triglyceride concentrations were also higher. Our results demonstrated no difference in fibrinogen and in TAT fragment concentrations among patients and controls. E-selectin concentrations were higher in patients than in controls (26.1 +/- 11 vs. 10.7 +/- 6.2 microg/l, P = 0.0001). P-selectin, sICAM-1, sVCAM-1, IL-6, MCP-1 and CRP were similar in the two groups. Vascular reactivity and carotid intima-media thickness (IMT) were also similar in patients and controls. After 1 year of GH treatment we found no changes in biochemical parameters, fibrinolytic markers, soluble adhesion molecules, inflammatory cytokines and endothelial function. CONCLUSION: Adults with GHD show some subtle changes in soluble adhesion molecules but our data suggest no beneficial effects of GH over these markers in relationship to endothelial function. Factors other than GH treatment, such as differences in age, degree of obesity, the presence of diabetes mellitus and arterial hypertension or tobacco consumption, could explain the observed increase in markers of vascular risk in GH-deficient patients.

Mutation analysis of HPS1, the gene mutated in Hermansky-Pudlak syndrome, in patients with isolated platelet dense-granule deficiency.

BACKGROUND AND OBJECTIVES: Isolated platelet dense granule (PDG) deficiency is a heterogeneous disorder frequently found among patients with mild to moderate bleeding diatheses. However, the molecular basis of this disorder is unknown. Genes involved in other rare bleeding disorders with associated reduction in the numbers of platelet dense-granules may play a role in isolated PDG deficiency. Among such genes, HPS1 is known to play a key role in the genesis of PDG and as many as 18 different HPS1 mutations have been identified in patients with Hermansky-Pudlak syndrome. Recently, we have identified subjects with one HPS1 heterozygous mutation displaying significant reductions in PDG without the clinical phenotype of Hermansky-Pudlak syndrome. This suggested that HPS1 mutations could be involved in isolated PDG deficiency. DESIGN AND METHODS: We sequenced all coding exons, and flanking intron regions of HPS1 in 16 patients with mild to severe PDG deficiency, most of whom had mild bleeding episodes. Nine patients reported a familial history of bleeding diathesis with PDG deficiency. We also evaluated the prevalence of HPS1 variations in 215 controls. Transmission electron microscopy was used to evaluate the number and morphology of PDG from patients and selected controls. RESULTS: No patient with PDG deficiency carried severe mutations of the HPS1 gene. We identified 6 previously described and 5 new polymorphisms in the HPS1 gene. Platelet electron microscopy in controls carrying these polymorphisms revealed that they did not significantly modify the number or morphology of PDG. INTERPRETATION AND CONCLUSIONS: Mutations affecting the HPS1 gene play a minor role in isolated PDG deficiency. These results support a molecular heterogeneity responsible for the number and morphology of PDG.

Phosphotyrosine proteins in platelets from patients with storage pool disease: direct relation between granule defects and defective signal transduction.

BACKGROUND AND OBJECTIVES: Storage pool diseases (SPD) are heterogeneous disorders associated with an abnormal presence of intraplatelet granules, which cause mild to moderate bleeding diathesis. We investigated signaling through tyrosine phosphorylation of proteins occurring in platelets with total or partial absence of dense- and alpha-granules in response to activation. DESIGN AND METHODS: We included a patient with severe delta-SPD, a patient with severe alpha-SPD or gray platelet syndrome, and six patients with partial deficiency of dense or a-granules. SPD was confirmed by electron microscopy evaluation of platelet ultrastructure. Platelet function was evaluated by bleeding time determination and conventional aggregometry. Platelet suspensions were activated with collagen and thrombin to analyze changes in tyrosine phosphorylation of proteins by electrophoresis and Western-blotting. RESULTS: Bleeding times were prolonged in all the patients included. Aggregation responses were slightly decreased in delta-SPD and normal in the rest of patients. Tyrosine phosphorylation in platelets from patients with partial forms of SPD was equivalent to that observed in control platelets, absent in response to collagen and thrombin activation in delta-SPD, and deficient only to thrombin activation in alpha-SPD. INTERPRETATION AND CONCLUSIONS: Tyrosine phosphorylation of proteins in activated platelets is highly dependent on the substances contained in the dense-granules and moderately dependent on those contained in the alpha-granules. A minimum amount of intraplatelet granules ensures signaling through tyrosine phosphorylation of proteins.

Multicentre evaluation of IL Test Free PS: a fully automated assay to quantify free protein S.

Deficiency of the anticoagulant vitamin K-dependent protein S (PS) is associated with increased risk of venous thrombosis. In human plasma, PS circulates in two forms: as free protein (free PS) and PS bound to C4b-binding protein (C4BP), a regulator of the complement system. Assays for free PS have higher sensitivity and specificity for protein S deficiency than assays for total protein S. We have extensively evaluated the analytical performance of a novel assay for free PS, the IL Test Free Protein S, which takes advantage of the affinity of C4BP for free PS, and compared its performance to existing methods. IL Test Free Protein S is a rapid, fully automated turbidimetric assay consisting of two reagents: a C4BP coated latex and an anti-PS monoclonal antibody coated latex. The test range, precision and linearity were adequate and the assay tolerated high concentrations of interfering substances of clinical significance. The reference range agreed with previously published studies. The analysis of 903 patient samples belonging to 20 different clinical categories with the new assay yielded free PS results that agreed well with those obtained using the assays established in the participating laboratories. The study demonstrated the IL Test Free Protein S to be rapid, reliable and easy to perform.