Thrombosis and Haemostasis Thrombosis and Haemostasis th de-de Sun, 26 Feb 17 22:38:47 +0100 Ahead of print: Pregnancy outcome of first trimester exposure to the vitamin K antagonist... The aim of this observational cohort study was to specify the risk of the vitamin K antagonist (VKA) phenprocoumon during first trimester of pregnancy, in particular to estimate the risk of birth defects and spontaneous fetal loss. Four hundred eight pregnancies with phenprocoumon exposure were compared to 1,642 pregnancies neither exposed to VKA nor to other major teratogens or fetotoxicants. There was no typical warfarin embryopathy in our exposed cohort. However, the overall rate of major birth defects was significantly increased (7.4 % vs 2.3 %; adjusted odds ratio [ORadj] 2.14; 95 % confidence interval [CI] 1.4–3.4). With early cessation until five completed gestational weeks the birth defect risk was similar to the comparison cohort (2.4 % vs 2.3 %; ORadj 1.07; 95 % CI 0.2–3.6). With treatment duration exceeding seven gestational weeks the rate of major birth defects increased up to five-fold (10.8 % vs 2.3 %; ORadj 5.18; 95 % CI 2.0–11.6). The overall risk of spontaneous abortion (SAB) was 38.0 % vs 17.5 % in the comparison cohort (adjusted hazard ratio (HRadj) 2.9; 95 % CI 2.2–3.9). The treatment duration had a significant effect on the hazard of SAB (HRadj 1.12; 95 % CI 1.01–1.25 per each additional exposure week). Phenprocoumon and other VKA carry an embryotoxic risk. This risk seems to be time-dependent with a steep risk increase for birth defects and also for fetal loss after week 5. If maternal disease permits, VKA therapy should be switched to safer alternatives such as heparins immediately after early recognition of pregnancy.... E. Hüttel (1), S. Padberg (1), R. Meister (2), E. Beck (1), C. Schaefer (1) 27243 2017-02-23 09:16:29 Ahead of print: Are cardiovascular risk factors also associated with the incidence of atrial... Established primary prevention strategies of cardiovascular diseases are based on understanding of risk factors, but whether the same risk factors are associated with atrial fibrillation (AF) remains unclear. We conducted a systematic review and field synopsis of the associations of 23 cardiovascular risk factors and incident AF, which included 84 reports based on 28 consented and four electronic health record cohorts of 20,420,175 participants and 576,602 AF events. We identified 3-19 reports per risk factor and heterogeneity in AF definition, quality of reporting, and adjustment. We extracted relative risks (RR) and 95 % confidence intervals [CI] and visualised the number of reports with inverse (RR [CI]<1.00), or direct (RR [CI]>1.00) associations. For hypertension (13/17 reports) and obesity (19/19 reports), there were direct associations with incident AF, as there are for coronary heart disease (CHD). There were inverse associations for non-White ethnicity (5/5 reports, with RR from 0.35 to 0.84 [0.82–0.85]), total cholesterol (4/13 reports from 0.76 [0.59–0.98] to 0.94 [0.90–0.97]; 8/13 reports with non-significant inverse associations), and diastolic blood pressure (2/11 reports from 0.87 [0.78–0.96] to 0.92 [0.85–0.99]; 5/11 reports with non-significant inverse associations), and direct associations for taller height (7/10 reports from 1.03 [1.02–1.05] to 1.92 [1.38–2.67]), which are in the opposite direction of known associations with CHD. A systematic evaluation of the available evidence suggests similarities as well as important differences in the risk factors for incidence of AF as compared with other cardiovascular diseases, which has implications for the primary prevention strategies for atrial fibrillation.... V. Allan (1), S. Honarbakhsh (2), J.-P. Casas (1), J. Wallace (1), R. Hunter (2), R. Schilling (2), P. Perel (3), K. Morley (4), A. Banerjee (1), H. Hemingway (1) 27242 2017-02-23 08:30:49 Ahead of print: High levels of latent antithrombin in plasma from patients with antithrombin... Antithrombin is an anticoagulant serpin that efficiently inhibits multiple procoagulant proteases. The cost for the structural flexibility required for this function is the vulnerability to mutations that impact its folding pathway. Most conformational mutations identified in serpins cause polymerisation. Only three mutations in SERPINC1 affecting two residues have been found to favour transformation to the latent conformation of antithrombin, another hyperstable non-anticoagulant form with strong antiangiogenic activity that constitutes 3 % of plasma antithrombin in healthy subjects. The analysis of latent antithrombin in 141 unrelated patients with antithrombin deficiency carrying 89 different SERPINC1 mutations identified four cases with higher levels than that of controls: p.Pro439Thr, p.Pro461Ser, p.Met283Val, and p.His401Tyr, the last also with circulating polymers. Heating of plasma at 42ºC exacerbated the transformation to the latent conformation in p.Pro439Thr and p.Pro461Ser. The conformational effect of p.Met283Val, the mutation associated with the highest levels of latent antithrombin detected in four members of a family, was verified in a recombinant model. Antithrombin deficiency in these cases should be classified as pleiotropic based on the impaired reactivity and low heparin affinity of the variant. Despite high levels of latent antithrombin (up to 80 µg/ml in p.Met283Val carriers), no vascular defects were described in carriers of these mutations. In conclusion, our study identifies new residues involved in the structural stability of antithrombin (and potentially of all serpins). High levels of endogenous latent antithrombin seem to play a minor antiangiogenic effect. Finally, pleiotropic deficiencies may be caused by mutations inducing transformation to the latent conformation.... M. de la Morena-Barrio (1, 2), E. Sandoval (3), P. Llamas (4), E. Wypasek (5, 6), M. Toderici (1), J. Navarro-Fernández (1), A. Rodríguez-Alen (3), N. Revilla (1), R. López-Gálvez (1), A. Miñano (1), J. Padilla (1), B. de la Morena-Barrio (1), J. Cuesta (3), J. Corral (1, 2), V. Vincente (1, 2) 27241 2017-02-23 08:29:50 Ahead of print: Detection of procoagulant imbalance Each individual possesses his/her own endogenous-thrombin-potential (ETP) (i. e. the ability to generate thrombin) which depends on the relative strength of the pro- and anticoagulant drivers operating in plasma. This ability depends in turn on the clinical conditions in which the balance between the two drivers is variably affected. One of the major determinants of this balance is the factor (F)VIII-protein C(PC) axis and its effect can be conveniently explored by the thrombin generation procedures with results expressed as ETP ratio with/without thrombomodulin (TM) (ETP-TM ratio). Furthermore, owing to the many feedback mechanisms mediated by thrombin (e. g. activation of PC, FXI, FV, FVIII, platelets etc.) it is also possible that any perturbation of the balance between pro- and anticoagulants that may occur in plasma even outside the FVIII-PC axis could result in an increased ETP-TM ratio and therefore may suggest a procoagulant imbalance. Indeed, other non-coagulation moieties (e. g. microparticles, neutrophil extracellular traps, pro-inflammatory cytokines and others) circulating in blood of patients with various clinical conditions may also contribute to the procoagulant imbalance even when FVIII and/or PC are apparently normal. It can be postulated that dual ETP measurements performed in the presence and absence of TM with results expressed as their ratio may be the candidate procedure to detect subtle procoagulant imbalance in many clinical conditions characterised by an increased risk of thromboembolism. This article aimed at reviewing the clinical conditions in which evidence for the value of the ETP-TM ratio has been provided.... A. Tripodi (1) 27240 2017-02-23 08:28:56 Ahead of print: Platelet turnover predicts outcome after coronary intervention Elevated platelet turnover contributes to high platelet reactivity. High platelet reactivity after percutaneous coronary intervention (PCI) is associated with major adverse cardiovascular events (MACE). The purpose of this study was to determine the prognostic value of platelet turnover and function with regard to MACE after PCI with stent implantation. In this prospective observational study, 486 consecutive patients after PCI on aspirin and clopidogrel were included to determine platelet turnover (mean platelet volume (MPV), reticulated platelet fraction (RPF)) and platelet function (multiple electrode aggregometry (MEA), vasodilator-stimulated phosphoprotein-phosphorylation (VASP-P) assay). At six-months follow-up, MACE occurred in 10.7 % of patients. RPF (odds ratio [OR]=1.173 (95% confidence interval [CI 95 %] 1.040–1.324), p=0.009) and MPV (OR=1.459 (CI 95 % 1.059–2.008), p=0.021) were univariable predictors of MACE, whereas VASP-P (OR=1.016 (CI 95 % 1.000–1.032), p=0.052) and MEA (OR=0.999 (CI 95 % 0.980–1.017), p=0.895) failed to predict MACE. RPF remained the only platelet variable independently associated with MACE. The best model to predict MACE included: troponin I (OR=1.007 (CI 95 % 1.002–1.012), p=0.009), RPF (OR=1.136 (CI 95 % 1.001–1.288), p=0.048), CRP (OR=1.008 (CI 95 % 1.001–1.014), p=0.023) and history of myocardial infarction (OR=2.039 (CI 95 % 1.093–3.806), p=0.025). RPF (OR=1.211 (CI 95 % 1.042–1.406), p=0.012) was also independently associated with in-hospital bleedings. In conclusion, RPF as index of platelet turnover is an independent predictor of MACE and bleeding events in PCI patients on dual antiplatelet therapy. Since RPF can reliably be quantified along with routine haemograms, RPF might easily be applied in the setting of cardiovascular risk prediction.... M. K. Freynhofer (1), L. Iliev (1), V. Bruno (1, 2), M. Rohla (1), F. S. Egger (1), T. W. Weiss (1), W. Hübl (3), M. Willheim (3), J. Wojta (4, 5), K. Huber (1, 4) 27239 2017-02-23 08:27:53 Ahead of print: CD14+CD16++ “nonclassical” monocytes are associated with endothelial dysfunction in... Endothelial dysfunction and inflammation are key mechanisms of vascular disease. We hypothesised that heterogeneity of monocyte subpopulations may be related to the development of vascular dysfunction in coronary artery disease (CAD). Therefore, we examined the relationships between monocyte subsets (CD14++CD16– “classical – Mon1”, CD14++CD16+ “intermediate – Mon2” and CD14+CD16++ “nonclassical – Mon3”), endothelial function and risk factor profiles in 130 patients with CAD undergoing coronary artery bypass grafting. This allowed for direct nitric oxide (NO) bioavailability assessment using isometric tension studies ex vivo (acetylcholine; ACh- and sodium-nitropruside; SNP-dependent) in segments of internal mammary arteries. The expression of CD14 and CD16 antigens and activation markers were determined in peripheral blood mononuclear cells using flow cytometry. Patients with high CD14+CD16++ “nonclassical” and low CD14++CD16- “classical” monocytes presented impaired endothelial function. High frequency of CD14+CD16++ “nonclassical” monocytes was associated with increased vascular superoxide production. Furthermore, endothelial dysfunction was associated with higher expression of activation marker CD11c selectively on CD14+CD16++ monocytes. Nonclassical and classical monocyte frequencies remained independent predictors of endothelial dysfunction when major risk factors for atherosclerosis were taken into account (β=0.18 p=0.04 and β=-0.19 p=0.03, respectively). In summary, our data indicate that CD14+CD16++ “nonclassical” monocytes are associated with more advanced vascular dysfunction measured as NO- bioavailability and vascular reactive oxygen species production.... K. Urbanski (1), D. Ludew (1), G. Filip (2), M. Filip (1), A. Sagan (1, 3), P. Szczepaniak (1), G. Grudzien (2), J. Sadowski (2), B. Jasiewicz-Honkisz (1), T. Sliwa (1), B. Kapelak (2), E. McGinnigle (3), T. Mikolajczyk (1, 3), T. J. Guzik (1, 3) 27238 2017-02-23 08:27:05 Ahead of print: Mutation in a highly conserved glycine residue in strand 5B of plasminogen activator... Serpinopathy is characterised as abnormal accumulation of serine protease inhibitors (SERPINs) in cells and results in clinical symptoms owing to lack of SERPIN function or excessive accumulation of abnormal SERPIN. We recently identified a patient with functional deficiency of plasminogen activator inhibitor-1 (PAI-1), a member of the SERPIN superfamily. The patient exhibited life-threatening bleeding tendencies, which have also been observed in patients with a complete deficiency in PAI-1. Sequence analysis revealed a homozygous single-nucleotide substitution from guanine to cytosine at exon 9, which changed amino acid residue 397 from glycine to arginine (c.1189G>C; p.Gly397Arg). This glycine was located in strand 5B and was well conserved in other serpins. The mutant PAI-1 was polymerised in the cells, interfering with PAI-1 secretion. The corresponding mutations in SERPINC1 (anti-thrombin III) at position 456 (Gly456Arg) and SERPINI1 (neuroserpin) at position 392 (Gly392Glu) caused an anti-thrombin deficiency and severe dementia due to intracellular retention of the polymers. Glycine is the smallest amino acid, and these mutated amino acids were larger and charged. To determine which factors were important, further mutagenesis of PAI-1 was performed. Although the G397A, C, I, L, S, T, and V were secreted, the G397D, E, F, H, K, M, N, P, Q, W, and Y were not secreted. The results revealed that the size was likely triggered by the polymerisation of SEPRINs at this position. Structural analyses of this mutated PAI-1 would be useful to develop a novel PAI-1 inhibitor, which may be applicable in the context of several pathological states.... T. Iwaki (1), K. Nagahashi (1, 2), K. Takano (3), K. Suzuki-Inoue (3), N. Kanayama (2), K. Umemura (1), T. Urano (4) 27237 2017-02-23 08:26:05 Ahead of print: Open Access: Pharmacokinetics of recombinant human soluble thrombomodulin in... Recombinant human soluble thrombomodulin (ART-123) is a novel anticoagulant for patients with disseminated intravascular coagulation (DIC). It is widely used in clinical settings throughout Japan. Furthermore, a global Phase 3 study is currently being conducted. In healthy subjects, ART-123 is excreted mainly via the kidneys. Therefore, ART-123 dose decrease was recommended in DIC patients with severe renal dysfunction. However, the pharmacokinetics of ART-123 in DIC patients with severe acute renal dysfunction has not been elucidated. In an open-label, multicentre, prospective, clinical pharmacological study, we investigated the pharmacokinetics and safety of ART-123 upon repeated administration to DIC patients. ART-123 was administered to patients at a dose of 130 or 380 U/kg/day for six consecutive days. Plasma concentrations of ART-123 were measured at 21 time points until eight days after the final administration. Urinary excretion rates during the first 24 hours (h) were calculated. Patient renal functions were evaluated by measuring 24-h creatinine clearance (Ccr). Forty-three patients were enrolled in the present study. The urinary excretion rates of ART-123 correlated closely with 24-h Ccr. Total body clearance of ART-123 was also weakly related with 24-h Ccr. However, the plasma concentrations of ART-123 were not considerably different among patients with different renal function. Two patients had subcutaneous haemorrhage as an adverse event related to ART-123. In conclusion, plasma concentrations of ART-123 may not be different among patients with different renal functions. ART-123 was well tolerated in these patients.... M. Hayakawa (1), S. Kushimoto (2), E. Watanabe (3), K. Goto (4), Y. Suzuki (5), T. Kotani (6), T. Kiguchi (7), T. Yatabe (8), J. Tagawa (9), F. Komatsu (9), S. Gando (1) 27236 2017-02-23 08:24:14 Ahead of print: Crushed sublingual versus oral ticagrelor administration strategies in patients with... Oral administration of crushed ticagrelor tablets turned out to be an efficacious method that improves its pharmacokinetics and pharmacodynamics. This strategy, however, is unlikely to eliminate the drug-drug interaction in patients receiving intravenous morphine, as the impairment of the P2Y12 inhibitor absorption related to decreased propulsive motility of the gastro-intestinal tract is the most likely mechanism of interaction. Thus, we designed a pharmacokinetic and pharmacodynamic study setting the feasibility of platelet inhibition with a loading dose of ticagrelor given as crushed tablets sublingually compared with two other ticagrelor loading dose administration strategies: integral tablet given orally and crushed tablet given orally in patients with unstable angina. Ticagrelor and its metabolite AR-C124900XX plasma concentration was evaluated in nine time points (time frame of 6 hours) using liquid chromatography coupled with mass spectrometry; platelet reactivity was evaluated using multiple electrode aggregometry. The area under the plasma concentration-time curve for ticagrelor and AR-C124900XX was significantly higher in patients treated with crushed tablets given orally compared with crushed tablets given sublingually only within the first hour after loading dose (936.9 ± 898.0 vs 368.0 ± 422.4, p=0.042 and 103.4 ± 120.8 vs 31.3 ± 43.9, p=0.031, respectively). Moreover, we showed significantly stronger platelet inhibition in patients receiving crushed ticagrelor orally vs. sublingually at 30 and 45 min after the loading dose (p=0,024 and p=0,016, respectively). Therefore, the administration strategy of ticagrelor determines the pharmacokinetic and pharmacodynamic profile of both ticagrelor and its active metabolite AR-C124900XX.... P. Niezgoda (1), J. Sikora (2), M. Barańska (1), A. Sikora (3), K. Buszko (4), E. Siemińska (1), M. P. Marszałł (3), J. M. Siller-Matula (5), B. Jilma (6), D. Alexopoulos (7), T. Fabiszak (1), J. Kubica (1) 27188 2017-02-16 08:36:42 Ahead of print: Small but mighty: Platelets as central effectors of host defense Platelets actively participate in inflammatory processes and drive diseases such as atherosclerosis, rheumatoid arthritis and cancer metastasis. However, platelets also have anti-inflammatory and anti-infective properties, which have received less consideration in the past. In this review, we highlight recent findings on the role of platelets in host defense and describe regulatory pathways modulating immune responses. Furthermore, we discuss the role of platelets for the resolution of inflammation and tissue repair. These conceptual changes contribute to our understanding of platelet physiology in disease. T. J. Stocker (1), H. Ishikawa-Ankerhold (1), S. Massberg (1, 2), C. Schulz (1, 2) 27187 2017-02-16 08:34:34 Ahead of print: JAM-C maintains VEGR2 expression to promote retinal pigment epithelium cell survival... Junctional adhesion molecule-C (JAM-C) has been shown to play critical roles during development and in immune responses. However, its role in adult eyes under oxidative stress remains poorly understood. Here, we report that JAM-C is abundantly expressed in adult mouse retinae and choroids in vivo and in cultured retinal pigment epithelium (RPE) and photoreceptor cells in vitro. Importantly, both JAM-C expression and its membrane localisation are downregulated by H2O2-induced oxidative stress. Under H2O2-induced oxidative stress, JAM-C is critically required for the survival of human RPE cells. Indeed, loss of JAM-C by siRNA knockdown decreased RPE cell survival. Mechanistically, we show that JAM-C is required to maintain VEGFR2 expression in RPE cells, and VEGFR2 plays an important role in keeping the RPE cells viable since overexpression of VEGFR2 partially restored impaired RPE survival caused by JAM-C knockdown and increased RPE survival. We further show that JAM-C regulates VEGFR2 expression and, in turn, modulates p38 phosphorylation. Together, our data demonstrate that JAM-C plays an important role in maintaining VEGR2 expression to promote RPE cell survival under oxidative stress. Given the vital importance of RPE in the eye, approaches that can modulate JAM-C expression may have therapeutic values in treating diseases with impaired RPE survival.... X. Jia (1), C. Zhao (2), Q. Chen (1), Y. Du (1), L. Huang (1), Z. Ye (1), X. Ren (1), S. Wang (1), C. Lee (1), Z. Tang (1), X. Li (1), R. Ju (1) 27186 2017-02-16 08:32:43 Ahead of print: SGK1 up-regulates Orai1 expression and VSMC migration during neointima formation... B. Walker-Allgaier (1), M. Schaub (1), I. Alesutan (2, 3, 4), J. Voelkl (2, 3), S. Geue (1), P. Münzer (1), J. M. Rodríguez (5), D. Kuhl (6), F. Lang (2), M. Gawaz (1), O. Borst (1) 27185 2017-02-16 08:30:54 Ahead of print: Identification of unique venous thromboembolism-susceptibility variants in... To identify novel single nucleotide polymorphisms (SNPs) associated with venous thromboembolism (VTE) in African-Americans (AAs), we performed a genome-wide association study (GWAS) of VTE in AAs using the Electronic Medical Records and Genomics (eMERGE) Network, comprised of seven sites each with DNA biobanks (total ~39,200 unique DNA samples) with genome-wide SNP data (imputed to 1000 Genomes Project cosmopolitan reference panel) and linked to electronic health records (EHRs). Using a validated EHR-driven phenotype extraction algorithm, we identified VTE cases and controls and tested for an association between each SNP and VTE using unconditional logistic regression, adjusted for age, sex, stroke, site-platform combination and sickle cell risk genotype. Among 393 AA VTE cases and 4,941 AA controls, three intragenic SNPs reached genome-wide significance: LEMD3 rs138916004 (OR=3.2; p=1.3E-08), LY86 rs3804476 (OR=1.8; p=2E-08) and LOC100130298 rs142143628 (OR=4.5; p=4.4E-08); all three SNPs validated using internal cross-validation, parametric bootstrap and meta-analysis methods. LEMD3 rs138916004 and LOC100130298 rs142143628 are only present in Africans (1000G data). LEMD3 showed a significant differential expression in both NCBI Gene Expression Omnibus (GEO) and the Mayo Clinic gene expression data, LOC100130298 showed a significant differential expression only in the GEO expression data, and LY86 showed a significant differential expression only in the Mayo expression data. LEMD3 encodes for an antagonist of TGF-β-induced cell proliferation arrest. LY86 encodes for MD-1down-regulates the pro-inflammatory response to lipopolysaccharide; LY86 variation was previously associated with VTE in white women; LOC100130298 is a non-coding RNA gene with unknown regulatory activity in gene expression and epigenetics.... J. A. Heit (1, 2), S. M. Armasu (3), B. M. McCauley (3), I. J. Kullo (1), H. Sicotte (3), J. Pathak (4), C. G. Chute (5), O. Gottesman (6), E. P. Bottinger (6), J. C. Denny (7, 8), D. M. Roden (9), R. Li (10), M. D. Ritchie (11), M. de Andrade (3) 27184 2017-02-16 08:27:43 Ahead of print: Abnormal vaginal bleeding in women with venous thromboembolism treated with apixaban... Abnormal vaginal bleeding can complicate direct oral anticoagulant (DOAC) treatment. We aimed to investigate the characteristics of abnormal vaginal bleeding in patients with venous thromboembolism (VTE) receiving apixaban or enoxaparin/warfarin. Data were derived from the AMPLIFY trial. We compared the incidence of abnormal vaginal bleeding between patients in both treatment arms and collected information on clinical presentation, diagnostic procedures, management and outcomes. In the AMPLIFY trial, 1122 women were treated with apixaban and 1106 received enoxaparin/warfarin. A clinically relevant non-major (CRNM) vaginal bleeding occurred in 28 (2.5 %) apixaban and 24 (2.1 %) enoxaparin/warfarin recipients (odds ratio [OR] 1.2, 95 % confidence interval [CI] 0.67–2.0). Of all CRNM bleeds, 28 of 62 (45 %) and 24 of 120 (20 %) were of vaginal origin in the apixaban and enoxaparin/warfarin group, respectively (OR 3.4; 95 % CI 1.8–6.7). Premenopausal vaginal bleeds on apixaban were characterised by more prolonged bleeding (OR 2.3; 95 %CI 0.5–11). In both pre- and postmenopausal vaginal bleeds, diagnostic tests were performed in six (21 %) and in seven (29 %) apixaban and enoxaparin/warfarin treated patients, respectively. Medical treatment was deemed not necessary in 16 (57 %) apixaban and 16 (67 %) enoxaparin/warfarin recipients. The severity of clinical presentation and course of the bleeds was mild in 75 % of the cases in both groups. In conclusion, although the absolute number of vaginal bleeding events is comparable between apixaban and enoxaparin/warfarin recipients, the relative occurrence of vaginal bleeds is higher in apixaban-treated women. The characteristics and severity of bleeding episodes were comparable in both treatment arms.... M. P. A. Brekelmans (1), L. J. J. Scheres (1, 2), S. M. Bleker (1), B. A. Hutten (3), A. Timmermans (4), H. R. Büller (1), S. Middeldorp (1) 27140 2017-02-09 08:21:37 Ahead of print: Incidence rates and case fatality rates of portal vein thrombosis and Budd-Chiari... Little information is available on the incidence of splanchnic vein thrombosis and on mortality rates during the acute phase of the disease. We performed a large epidemiologic study on hospital admissions for portal vein thrombosis (PVT) and the Budd-Chiari syndrome (BCS) between 2002 and 2012 in Northwestern Italy. Primary and secondary discharge diagnoses of PVT and BCS were identified using the 9th edition International Classification of Diseases codes 453.0, 572.1 and 452. Hospitalisations for recurrent events were not included. Information was collected on age and gender, vital status at discharge, duration of hospitalisation, and up to five secondary discharge diagnoses. Comorbidity was evaluated using the Charlson comorbidity index (CCI). A total of 3535 patients with PVT and 287 with BCS were hospitalized. The overall gender-specific incidence rates for PVT were 3.78 per 100,000 inhabitants in males and 1.73 per 100,000 inhabitants in females; for BCS 2.0 and 2.2 per million inhabitants, respectively. In-hospital case fatality was 7.3 % in patients with PVT and 4.9 % in patients with BCS. Age, non-abdominal solid cancer, and CCI were independently associated with in-hospital mortality in both PVT and BCS after stepwise regression analysis, male gender and haematologic cancer were associated with mortality in BCS patients only. In this large study we confirmed the low incidence of BCS and we found an incidence of PVT higher than previously reported. This incidence was stable during the period of observation. In-hospital mortality is not negligible, in particular in PVT patients.... W. Ageno (1), F. Dentali (1), F. Pomero (2), L. Fenoglio (2), A. Squizzato (1), G. Pagani (1), R. Re (3), M. Bonzini (4) 27139 2017-02-09 08:20:51 Ahead of print: Pharmacokinetics and pharmacodynamics of tecarfarin, a novel vitamin K antagonist... Tecarfarin is a vitamin K antagonist (VKA) with reduced propensity for drug interactions. To evaluate the pharmacokinetic (PK), pharmacodynamic (PD), and safety of tecarfarin, we performed single ascending dose (SAD) (n=66), multiple ascending dose (MAD) (n=43), and tecarfarin versus warfarin (n=28) studies in human volunteers. In the SAD, tecarfarin was administered to 5 of 6 subjects (1 received placebo) in each of 11 cohorts. AUC0-∞ exhibited linearity and dose proportionality. Elimination T1/2 ranged from 87–136 hours (h) across all doses. In the MAD, tecarfarin was administered to 5 of 6 volunteers in each of 7 cohorts. The starting dose was continued until the subject’s INR reached the target range (TR) of 1.7 to 2.0. Dosing was down-titrated if the TR was achieved. Elimination T1/2 ranged from 107–140 h. Doses <10 mg had insignificant effect on INR. Higher doses raised INRs and required down-titration to maintain the TR. Steady state INR dosing was 10–20 mg. INR declined promptly after discontinuation. In the comparative study, subjects received tecarfarin or warfarin and dose titrated to a TR of 1.5–2.0. Mean dose after TR was achieved was 13.9 mg (range 10.0–25.5 mg) for tecarfarin and 5.3 mg (range 2.5–9.0 mg) for warfarin. At similar INR levels, the concentration of coagulation factors II, VII, IX, and X were similar for tecarfarin and warfarin. Tecarfarin was tolerated well without serious adverse events in all three studies.... D. Albrecht (1), D. Ellis (2), D. M. Canafax (3), D. Combs (4), P. Druzgala (1), P. G. Milner (1), M. G. Midei (5) 27138 2017-02-09 08:19:40 Ahead of print: Risk assessment models for venous thromboembolism in acutely ill medical patients Although the use of thromboprophylaxis is recommended for acutely ill medical patients at increased risk of venous thromboembolism (VTE), it remains unclear which risk assessment model (RAM) should be routinely used to identify at-risk patients requiring thromboprophylaxis. We therefore aimed to describe existing RAMs, and to compare these tools in terms of validity and applicability for clinical decision-making. We performed a comprehensive systematic search in MEDLINE from the date of initiation until May 2016 for studies in acutely ill medical patients investigating validity of RAMs for VTE. Two reviewers independently screened the title, abstract, and full text, and evaluated the characteristics of studies, and the composition, evidence of validation, and results on validity of the RAMs. We included 11 studies assessing eight RAMs: 4-Element RAM, Caprini RAM, a full logistic model, Geneva risk score, IMPROVE-RAM, Kucher Model, a “Multivariable Model”, and Padua Prediction Score. The 4-Element RAM, IMPROVE-RAM, multivariable model, and full logistic model had derivation by identifying factors with predictive power. The other four RAMs were empirically generated based on consensus guidelines, published data, and clinical expertise. The Kucher Model, the Padua Prediction Score, the Geneva Risk Score and the IMPROVE-RAM underwent multicenter external validation. The Kucher Model, the Padua Prediction Score, and the Geneva Risk Score improved rates of thromboprophylaxis or clinical outcomes. In conclusion, existing RAMs to evaluate the need of thromboprophylaxis in acutely ill medical patients are difficult to compare and none fulfills the criteria of an ideal RAM. Nevertheless, the adequacy of thromboprophylaxis may be improved by implementing one of the validated RAMs.... A. K. Stuck (1), D. Spirk (2), J. Schaudt (3), N. Kucher (1) 27126 2017-02-02 10:01:09 Ahead of print: Imaging analyses of coagulation-dependent initiation of fibrinolysis on activated... Using intravital confocal microscopy, we observed previously that the process of platelet phosphatidylserine (PS) exposure, fibrin formation and lysine binding site-dependent plasminogen (plg) accumulation took place only in the center of thrombi, not at their periphery. These findings prompted us to analyse the spatiotemporal regulatory mechanisms underlying coagulation and fibrinolysis. We analysed the fibrin network formation and the subsequent lysis in an in vitro experiment using diluted platelet-rich plasma supplemented with fluorescently labelled coagulation and fibrinolytic factors, using confocal laser scanning microscopy. The structure of the fibrin network formed by supplemented tissue factor was uneven and denser at the sites of coagulation initiation regions (CIRs) on PS-exposed platelets. When tissue-type plasminogen activator (tPA; 7.5 nM) was supplemented, labelled plg (50 nM) as well as tPA accumulated at CIRs, from where fibrinolysis started and gradually expanded to the peripheries. The lysis time at CIRs and their peripheries (50 µm from the CIR) were 27.9 ± 6.6 and 44.4 ± 9.7 minutes (mean ± SD, n=50 from five independent experiments) after the addition of tissue factor, respectively. Recombinant human soluble thrombomodulin (TMα; 2.0 nM) attenuated the CIR-dependent plg accumulation and strongly delayed fibrinolysis at CIRs. A carboxypeptidase inhibitor dose-dependently enhanced the CIR-dependent fibrinolysis initiation, and at 20 µM it completely abrogated the TMα-induced delay of fibrinolysis. Our findings are the first to directly present crosstalk between coagulation and fibrinolysis, which takes place on activated platelets’ surface and is further controlled by thrombin-activatable fibrinolysis inhibitor (TAFI).... T. Brzoska (1), Y. Suzuki (1), H. Sano (1), S. Suzuki (1), M. Tomczyk (1), H. Tanaka (1), T. Urano (1) 27125 2017-02-02 09:59:56 Ahead of print: Chewing versus Swallowing Ticagrelor to Accelerate Platelet Inhibitionin Acute... It was the study objective to evaluate whether chewing a 180 mg loading dose of ticagrelor versus an equal dose of traditional oral administration, enhances inhibition of platelet aggregation 1 hour (h) after administering a ticagrelor loading dose in non-ST elevation myocardial infarction (NSTEMI) patients. Dual anti-platelet therapy represents standard care for treating NSTEMI patients. Ticagrelor is a direct acting P2Y12 inhibitor and, unlike clopidogrel and prasugrel, does not require metabolic activation. Fifty NSTEMI patients were randomised to receive either a chewing loading dose of 180 mg ticagrelor or an equal standard oral dose of ticagrelor. Platelet reactivity was evaluated by VerifyNow at baseline, 1 and 4 h post-loading dose. Results are reported in P2Y12 reaction units. Patients then continued to receive standard 90 mg oral ticagrelor twice daily. Baseline characteristics did not differ between the two groups. P2Y12 reaction units in the chewing group compared with the standard group at 0, 1 and 4 h after ticagrelor loading dose were: 245 vs 239 (p=0.59), 45 vs 130 (p=0.001) and 39 vs 60 (p=0.12), respectively, corresponding to a relative inhibition of platelet aggregation of 83 % vs only 47 % at 1 h (p< 0.001), and 84 % vs 77 % (p=0.59) at 4 h. Major adverse cardiac and cardiovascular events at 30 days were low (2 %), occurring in only one patient in the standard group. In conclusion, chewing a 180 mg ticagrelor loading dose is feasible and facilitates both faster and improved early inhibition of platelet aggregation in NSTEMI patients, compared with a standard oral-loading dose.... E. Asher (1), S. Frydman (1), M. Katz (1), E. Regev (1), A. Sabbag (1), I. Mazin (1), A. Abu-Much (1), A. Kukuy (1), A. Mazo (1), A. Erez (1), A. Berkovitch (1), M. Narodistky (1), I. Barbash (1), A. Segev (1), R. Beigel (1), S. Matetzky (1) 27124 2017-02-02 09:58:35 Ahead of print: Novel role of platelet reactivity in adverse left ventricular remodelling after... The role of platelet-leukocyte interaction in the infarct myocardium still remains unveiled. We aimed to determine the linkage of platelet activation to post-infarct left ventricular remodelling (LVR) process. REMODELING was a prospective, observational, cohort trial including patients (n = 150) with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention. Patients were given aspirin plus clopidogrel therapy (600 mg loading and 75 mg daily). Platelet reactivity (PRU: P2Y12 Reaction Units) was assessed with VerifyNow P2Y12 assay on admission. Transthoracic echocardiography was performed on admission and at one-month follow-up. The primary endpoint was the incidence of LVR according to PRU-based quartile distribution. LVR was defined as a relative ≥ 20 % increase in LV end-diastolic volume (LVEDV) between measurements. Adverse LVR was observed in 36 patients (24.0 %). According to PRU quartile, LVR rate was 10.8 % in the first, 23.1 % in the second, 27.0 % in the third, and 35.1 % in the fourth (p = 0.015): the optimal cut-off of PRU was ≥ 248 (area under curve: 0.643; 95 % confidence interval: 0.543 to 0.744; p = 0.010). LVR rate also increased proportionally according to the level of high sensitivity-C reactive protein (hs-CRP) (p = 0.012). In multivariate analysis, the combination of PRU (≥ 248) and hs-CRP (≥ 1.4 mg/l) significantly increased the predictive value for LVR occurrence by about 21-fold. In conclusion, enhanced levels of platelet activation and inflammation determined the incidence of adverse LVR after STEMI. Combining the measurements of these risk factors increased risk discrimination of LVR. The role of intensified antiplatelet or anti-inflammatory therapy in post-infarct LVR process deserves further study.... Y. Park (1), U. S. Tantry (2), J.-S. Koh (3), J.-H. Ahn (1), M. G. Kang (3), K. H. Kim (3), J. Y. Jang (1), H. W. Park (3), J.-R. Park (3), S.-J. Hwang (3), K.-S. Park (4), C. H. Kwak (1), J.-Y. Hwang (3), P. A. Gurbel (2), Y.-H. Jeong (1, 5) 27123 2017-02-02 09:57:36 Ahead of print: Fibrin clot structure - pro-fibrinolytic effect of oral contraceptives in apparently... Fibrin metabolism is influenced by many factors. The velocity of fibrin formation, genetic polymorphisms, fibrinolytic features and the structure of the fibrin clot are determinants of fibrin turnover. Oral contraceptives (OCs) have significant impact on the haemostatic system, by increasing the concentration of coagulation factors, plasminogen and tissue plasminogen activator activity, and decreasing the concentration of haemostatic inhibitors. The present study addresses the influence of OCs on fibrin structure and fibrin metabolism. The study included 70 women treated with seven different OC-formulations. Blood was collected at baseline and after six months of OCs. The plasma concentration of fibrinogen, thrombin-antithrombin complex (TAT), plasminogen, plasmin-antiplasmin complex (PAP), D-Dimer and thrombin generation measures were determined. Fibrin structure measures and fibrin clot lysis not affected by the plasma concentration of plasminogen activators and inhibitors were determined. OCs increased the concentration of fibrinogen, TAT, plasminogen, PAP and D-Dimer significantly and affected measures of thrombin generation (p<0.001). The maximal optical density of fibrin (p<0.001), the fibrin fibre density (p=0.03), fibrin fibre diameter (p=0.003), fibrin mass-length ratio (p<0.001) and lysis per hour (p<0.001) increased significantly upon OC-treatment. Lysis per hour was not correlated to the concentration of plasminogen. We conclude that the effect of OCs on the coagulation system is balanced by alterations in fibrin structure, facilitating clot lysis and contributing to the fibrinolytic susceptibility already present in women treated with OC. These alterations may counterbalance the OC-induced increased thrombin generation and reduced coagulation inhibitory potential, contributing to maintenance of the haemostatic balance in women receiving OCs.... J. J. Sidelmann (1, 2), C. Kluft (1, 3), A. H. Krug (1, 2), U. Winkler (4), J. Jespersen (1, 2), J. B. Gram (1, 2) 27122 2017-02-02 09:56:46 Ahead of print: From thrombosis to fibrosis in chronic thromboembolic pulmonary hypertension The pathomechanisms underlying the development of thrombofibrotic pulmonary artery occlusions in Chronic Thromboembolic Pulmonary Hypertension (CTEPH) are largely unknown. The aim of this study was to allocate distinct cellular processes playing a role in thrombus resolution, such as inflammation, hypoxia, proliferation, apoptosis and angiogenesis, to different stages of thrombofibrotic remodelling. A total of 182 pulmonary endarterectomy (PEA) specimens were collected from 31 CTEPH patients. To facilitate co-localisation, Tissue MicroArrays were prepared and processed for (immuno)-histochemistry and confocal fluorescence microscopy. Murine venous thrombus formation and resolution was examined after inferior vena cava ligation. PEA tissues exhibited five morphologically distinct regions predominantly consisting of either fibrin-, erythrocyte- or extracellular matrix-rich thrombus, myofibroblasts, vessels or fibrotic tissue, and were found to resemble chronological stages of thrombus resolution in mice. Cellularity was highest in vessel-rich regions, and numerous cells were strongly positive for HIF1α or HIF2α as well as markers of activated VEGF signalling, including endothelial nitric oxide synthase. On the other hand, negative regulators of angiogenic growth factor signalling and reactive oxygen species were also highly expressed. Immune cells, primarily macrophages of the M2 subtype and CD117 haematopoietic progenitors were detected and highest in vascularised regions. Our findings demonstrate the simultaneous presence of different stages of thrombus organisation and suggest that hypoxia-induced endothelial, mesenchymal and immune cell activation may contribute to thrombofibrosis in CTEPH. This systematic histological characterisation of the material obstructing pulmonary vessels in CTEPH may provide a valuable basis for further studies aimed at determining causal factors underlying this disease.... M. L. Bochenek (1, 2, 3), N. S. Rosinus (1, 3), M. Lankeit (2), L. Hobohm (1, 2), F. Bremmer (4), E. Schütz (1), F. A. Klok (2), S. Horke (2, 5), C. B. Wiedenroth (6), T. Münzel (1), I. M. Lang (7), E. Mayer (6), S. Konstantinides (2, 8), K. Schäfer (1, 3) 27121 2017-02-02 09:55:47 Ahead of print: Prediction of major and clinically relevant bleeding in patients with VTE treated... Better understanding of risk factors for major bleeding events during anticoagulant treatment for venous thromboembolism (VTE) may help physicians when deciding on intensity and duration of treatment. The primary aim of this study was to identify risk factors for major and clinically relevant bleeding in patients receiving the oral factor Xa inhibitor edoxaban or warfarin for the treatment of acute VTE. We analysed data from 8240 patients who received ≥1 dose of study drug in the Hokusai-VTE study. Bleeding risk factors were evaluated in 4118 patients who received edoxaban and significant variables were combined in a prediction model. We used the C-statistic to estimate model discrimination and bootstrap techniques for internal validation. Major bleeding occurred in 56/4118 (1.4 %) patients given edoxaban and in 66/4122 (1.6 %) patients given warfarin. Clinically relevant bleeding occurred in 349 (8.5 %) and 423 (10.3 %), respectively. Significant risk factors for major bleeding during edoxaban treatment were female sex, concomitant antiplatelet therapy, haemoglobin ≤10 g/dl, history of arterial hypertension, and systolic blood pressure >160 mmHg. The discrimination of the model was high (C-statistic: 0.71) for major bleeding, lower for clinically relevant bleeding (C-statistic: 0.62) and when the model was applied to patients receiving warfarin (C-statistic 0.60). In conclusion, we identified five main predictors of major bleeding in patients receiving edoxaban for the treatment of acute VTE. A risk model based on these factors predicted an increased risk of bleeding with good discrimination.... M. Di Nisio (1, 2), G. Raskob (3), H. R. Büller (2), M. A. Grosso (4), G. Zhang (5), S. M. Winters (6), A. Cohen (7) 27120 2017-02-02 09:54:09 Ahead of print: Performance of the 20-minute whole blood clotting test in detecting venom induced... The 20-minute whole blood clotting test (WBCT20) is used as a bedside diagnostic test for coagulopathic snake envenoming. We aimed to assess the performance of the WBCT20 in diagnosis of venom induced consumption coagulopathy (VICC) in Russell’s viper envenoming. Adult patients admitted with suspected snake bites were recruited from two hospitals. WBCT20 and prothrombin time (PT) test were performed on admission. WBCT20 was done by trained clinical research assistants using 1 ml whole blood in a 5 ml borosilicate glass tube with a 10 mm internal diameter. The PT was measured by a semi-automated coagulation system and international normalised ratio (INR) calculated. VICC was defined as present if the INR was >1.4. The diagnostic utility of WBCT20 was determined by calculating the sensitivity and specificity of the WBCT20 on admission for detecting VICC. There were 987 snake bites where both WBCT20 and PT were done on admission samples. This included 79 patients (8 %) with VICC. The WBCT20 was positive in 65/79 patients with VICC (sensitivity 82 %; 95 % confidence interval [CI]: 72–90 %) and was falsely positive in 13/908 with no coagulopathy. The WBCT20 was negative in 895/908 snake bites with no coagulopathy (specificity: 98 % 95 % CI: 97–99 %) and was falsely negative in 14/79 with VICC. Using trained clinical staff, the WBCT20 test had a relatively good sensitivity for the detection of VICC, but still missed almost one fifth of cases where antivenom was potentially indicated.... I. Ratnayake (1), F. Shihana (1), D. M. Dissanayake (1, 2), N. A. Buckley (1, 3), K. Maduwage (4, 5), G. K. Isbister (1, 4) 27119 2017-02-02 09:52:56 Ahead of print: Nucleic acids as cofactors for factor XI and prekallikrein activation: Different... The plasma zymogens factor XI (fXI) and prekallikrein (PK) are activated by factor XIIa (fXIIa) during contact activation. Polyanions such as DNA and RNA may contribute to thrombosis and inflammation partly by enhancing PK and fXI activation. We examined PK and fXI activation in the presence of nucleic acids, and determine the effects of the cofactor high molecular weight kininogen (HK) on the reactions. In the absence of HK, DNA and RNA induced of fXI autoactivation. Proteases known to activate fXI (fXIIa and thrombin) did not enhance this process appreciably. Nucleic acids had little effect on PK activation by fXIIa in the absence of HK. HK had significant but opposite effects on PK and fXI activation. HK enhanced fXIIa activation of PK in the presence of nucleic acids, but blocked fXI autoactivation. Thrombin and fXIIa could overcome the HK inhibitory effect on autoactivation, indicating these proteases are necessary for nucleic acid-induced fXI activation in an HK-rich environment such as plasma. In contrast to PK, which requires HK for optimal activation, fXI activation in the presence of nucleic acids depends on anion binding sites on the fXI molecule. The corresponding sites on PK are not necessary for PK activation. Our results indicate that HK functions as a cofactor for PK activation in the presence of nucleic acids in a manner consistent with classic models of contact activation. However, HK has, on balance, an inhibitory effect on nucleic acid-supported fXI activation and may function as a negative regulator of fXI activation.... I. Ivanov (1), M. Sun (1), S. K. Dickeson (1), C. Puy (2), O. J. T. McCarty (2), A. Gruber (2), A. Matafonov (1, 3), D. Gailani (1) 27095 2017-01-26 09:45:23