A case of COVID-19 vaccination-associated forme fruste purpura fulminans.

We report the case of a female, 77 year old patient with multi-localized skin infarctions following vaccination with mRNA-1273 (Moderna). This phenomenon is to our knowledge otherwise only seen in infection-associated purpura fulminans - which was thoroughly ruled out in our patient. This report demonstrates that we need to be vigilant of a wider array of vascular phenomena related to Covid vaccinations.

Abnormal vaginal bleeding in women of reproductive age treated with edoxaban or warfarin for venous thromboembolism: a post hoc analysis of the Hokusai-VTE study.

OBJECTIVE: To investigate the characteristics and outcome of abnormal vaginal bleeding in women receiving edoxaban or warfarin for treatment of venous thromboembolism (VTE). DESIGN AND SETTING: Post hoc analysis of the Hokusai-VTE study, a multicentre, randomised, double-blind trial comparing edoxaban with warfarin for acute symptomatic VTE. POPULATION: Women below 50 years receiving edoxaban or warfarin for treatment of VTE. METHODS: We collected data on diagnostic measures, treatment, and clinical outcome of abnormal vaginal bleeding events. MAIN OUTCOME MEASURES: Occurrence of major and clinically relevant nonmajor (CRNM) abnormal vaginal bleeding events. RESULTS: In all, 628 women aged under 50 years were treated with edoxaban and 665 with warfarin. The rate of abnormal vaginal bleeding was 15/100 person-years (py) (95% CI 11-19) in women receiving edoxaban and 9/100 py (95% CI 6-12) in the warfarin group (hazard ratio: 1.7, 95% CI 1.1-2.5). Major abnormal vaginal bleeding occurred in eight (1.3%) women on edoxaban and in three (0.9%) women receiving warfarin [odds ratio (OR) 2.8; 95% CI 0.8-10.8], and CRNM abnormal vaginal bleeding occurred in 53 (8.4%) women treated with edoxaban and in 37 (5.6%) on warfarin therapy (OR 1.6, 95% CI 1.0-2.4). Over 85% of all vaginal bleeds were characterised by heavy menstrual bleeding. Major bleeds frequently required treatment, and in more than 75% of patients anticoagulant therapy was adjusted. The severity of clinical presentation and course of major and CRNM bleeds was mild in most patients. CONCLUSIONS: Abnormal vaginal bleeding occurred more frequently in women treated with edoxaban than with warfarin. Reassuringly, most events could be managed conservatively and had a mild outcome. TWEETABLE ABSTRACT: Abnormal vaginal bleeding occurred more frequently in women treated with edoxaban than with warfarin.

Effects of clopidogrel with or without aspirin on the generation of extracellular vesicles in the microcirculation and in venous blood: A randomized placebo controlled trial.

BACKGROUND: Dual-antiplatelet therapy (DAPT) is a standard strategy in acute coronary heart disease; however, it confers a considerable bleeding risk. Single-antiplatelet therapy (SAPT) inhibits haemostatic system activation ex vivo to a similar extent as DAPT. Extracellular vesicles (EV) are procoagulant and contribute to haemostatic system activation. We aimed to investigate the effect of DAPT compared with SAPT on EV. METHODS: In a randomized, double-blind, placebo-controlled trial, 44 healthy volunteers received DAPT (clopidogrel + aspirin) or SAPT (clopidogrel + placebo) for 7 days. Blood was obtained from a standardized microvascular injury and through venipuncture at baseline (BL) and at 2 h, 24 h, and 8 days after treatment initiation. The number, origin, and surface expression of EV were assessed using flow cytometry. Data are given as median (quartiles). Non-parametric tests were used to evaluate the short-term (BL vs 2 h) and long-term differences (2 h to 8 days), as well as the differences between treatment groups. RESULTS: There was no difference either in the short-term effects on the number (×103 mL-1) of EV in microvascular blood between DAPT [BL: 1433 (653; 3184) vs 2 h: 862 (545; 2026), p = 0.39] and SAPT [(BL: 614 (552; 1402) vs 2 h: 1079 (781; 1538), p = 0.75)] or in the long-term effects. DAPT and SAPT did not exhibit differential short-term effects on the number and proportion (36% and 27% vs 55% and 36%) of platelet-derived EV. DAPT and SAPT resulted in a significant short-term increase in phosphatidylserine expression in microvascular blood. The effects of DAPT and SAPT on EV in venous blood were similar to those in microvascular blood. CONCLUSION: DAPT and SAPT have comparable effects on the amount, origin, and surface characteristics of EV.

High proportion of patients with bleeding of unknown cause in persons with a mild-to-moderate bleeding tendency: Results from the Vienna Bleeding Biobank (VIBB).

INTRODUCTION: Data on clinical characteristics and the prevalence of underlying coagulopathies in patients with mild-to-moderate bleeding disorders (MBDs) are scarce. AIM: We established the Vienna Bleeding Biobank (VIBB) to characterize and thoroughly investigate Austrian patients with MBDs. RESULTS: Four hundred eighteen patients (female = 345, 82.5%) were included. A platelet function defect (PFD) was diagnosed in 26 (6.2%) and a possible PFD in 30 (7.2%) patients. Eight patients (1.9%) were diagnosed with von Willebrand disease (VWD) (type 1 n = 6; type 2 n = 2), and 29 patients had low VWF (30-50 IU/dL). Deficiencies in factor VIII, IX, XI or XIII were found in 11 (2.6%), 3 (0.7%), 3 (0.7%) and 1 patient(s), 2 patients had dysfibrinogenaemia, and further 2 had possible PFD and FXI deficiency. Probable causal mutations were detected in 8 of 11 patients with FVIII deficiency, 2 of 3 patients with FIX deficiency and 2 of 8 patients with VWD. Three hundred three patients (72.5%) had normal results in the coagulation assays and were categorized as patients with bleeding of unknown cause (BUC). The bleeding score did not differ between patients with and without established diagnosis. A diagnosis of a bleeding disorder was more frequently made in men than in women (49.3% vs 22.9%). Male sex (OR 3.55, 95% CI: 2.02-6.22; P < .001) and blood group 0 (OR 1.86, 95% CI: 1.17-2.94; P = .008) were independently associated with diagnosis of a bleeding disorder. CONCLUSION: The high rate of patients with BUC despite in-depth haemostatic assessment underlines the incompleteness of available routine laboratory tests. Males with MBDs were more likely to be diagnosed with an established bleeding disorder than females.

Natural antibodies to oxidation-specific epitopes: innate immune response and venous thromboembolic disease.

Essentials Natural antibodies to oxidation-specific epitopes have antithrombotic properties. We evaluated the relation between natural IgM and IgG antibodies and the venous thrombosis risk. Risk of recurrent thrombosis was higher in patients with low natural IgM antibody levels. The protective effect of high IgM levels suggests a role of innate immune response in thrombosis. SUMMARY: Background and objectives Natural antibodies to oxidation-specific epitopes protect from atherothrombotic events. Whether mechanisms of innate immunity are relevant in the pathogenesis of venous thromboembolism (VTE) is unknown. Patients/Methods We measured plasma levels of immunoglobulin M (IgM) antibodies to oxidized low-density lipoproteins (OxLDL) and phosphocholine (PC) by enzyme linked immune assay in 663 patients with unprovoked VTE, who were prospectively followed after discontinuation of anticoagulation for a median of 8.8 years. The study endpoint was recurrent VTE. Results IgM antibody levels to OxLDL and PC were higher in patients without compared to those with recurrent VTE (n = 174, 26.2%). For each doubling of OxLDL-IgM or PC-IgM the hazard ratio (HR) of recurrence was 0.88 (95% confidence interval [CI], 0.77-1.01) and 0.82 (95% CI, 0.71-0.94), respectively. After 5 years the probability of recurrence in patients with PC-IgM levels in the highest tertile (> 19.6 RLU/100 ms) was 13.0% (95% CI, 8.1-17.6%), compared with 21.1% (95% CI, 14.9-26.9%) in the middle tertile and 20.6% (95% CI, 14.7-26.0%) in the lowest tertile. The corresponding HR was 0.56 (0.39-0.82) for PC-IgM levels in the highest compared with the lowest tertile. Neither immunoglobulin G IgG antibody levels to OxLDL nor those to PC were associated with risk of VTE. Conclusion Levels of natural IgM antibodies to oxidation-specific epitopes are inversely related to the risk of VTE.

Risk of cancer after anticoagulation in patients with unprovoked venous thromboembolism: an observational cohort study.

Essentials Data on long-term cancer risk are controversial in patients with venous thromboembolism (VTE). We assessed long-term rates and risk factors of cancer in patients with VTE. Cancer risk after anticoagulation is not higher in VTE patients than in the general population. VTE recurrence is not predictive of a future cancer diagnosis. SUMMARY: Background Patients with venous thromboembolism (VTE) are at risk of having a subsequent cancer diagnosis. The risk is highest during the first 6 months. Reports on cancer rates thereafter are controversial. We aimed to assess long-term rates and risk factors of cancer in patients with VTE. Methods and Results We followed patients with a first unprovoked VTE after discontinuation of anticoagulation, and excluded those receiving long-term antithrombotic therapy or with major thrombophilia. The study endpoint was the occurrence of cancer. Sixty-two (5.2%) of 1188 patients developed cancer during a median follow-up of 98 months. The cumulative incidence rates of cancer were 0.7% (95% confidence interval [CI] 0.2-1.2%), 3.1% (95% CI 2.0-4.1%) and 9% (95% CI 6.5-11.5) after 1, 5 and 15 years; these were not significantly different from those in the matched general population (0.6%, 3.4%, and 12.2%, respectively). The corresponding standardized incidence ratios (ratio of the observed cancer cases and the number of cases based on national cancer incidence rates) of 1.1 (95% CI 0.5-2.5), 1.0 (95% CI 0.6-1.4) and 0.9 (95% CI 0.7-1.2) did not indicate a difference in cancer incidence between our cohort and the general population. Advancing age (hazard ratio [HR] per decade 1.5, 95% CI 1.2-2.0) and shorter duration of anticoagulation (HR per 1-month decrease 1.3, 95% CI 1.1-1.6) were associated with an increased cancer risk, whereas VTE recurrence was not (HR 1.17, 95% CI 0.66-2.07). Conclusions Asymptomatic patients with unprovoked VTE who have completed anticoagulation therapy do not have a higher cancer risk. The inverse association between the duration of anticoagulation and the incidence of cancer warrants further investigation.

Oral contraception and menstrual bleeding during treatment of venous thromboembolism: Expert opinion versus current practice: Combined results of a systematic review, expert panel opinion and an international survey.

INTRODUCTION: The optimal management of oral contraception and menstrual bleeding during treatment of venous thromboembolism (VTE) is largely unknown. We aimed to elicit expert opinion and compare that to current practice as assessed by a world-wide international web-based survey among physicians. METHODS: 10 international thrombosis experts and 10 abnormal uterine bleeding experts independently completed a questionnaire containing three hypothetical patient cases each with four different scenarios, and additional queries covering different severities of VTE, patient circumstances, hormonal contraceptives and both thrombotic and bleeding complications. The consensus percentage was set a priori at ≥70%. The same questionnaire with randomized case scenarios was presented to international physicians via newsletters of the ISTH and national scientific communities. Differences between the expert groups and daily clinical care were assessed. RESULTS: Expert recommendations were divergent and differed in several important points from clinical practice. In contrast to common practice in which contraceptives are discontinued at the moment of a VTE diagnosis, the thrombosis experts agreed to continue oral contraception (OC) during the anticoagulation treatment period. Also, experts reached consensus on treating patients with anticoagulation-associated abnormal uterine bleeding with tranexamic acid, although this is not supported by strong evidence from the literature. No consensus was reached on the optimal anticoagulant drug class. CONCLUSIONS: International experts' opinions on handling of contraceptives and management of anticoagulant-associated abnormal uterine bleeding in female VTE patients are divergent and management in clinical practice is heterogeneous. There is a great need of further studies on these topics.

The long-term recurrence risk of patients with unprovoked venous thromboembolism: an observational cohort study.

Essentials Long-term recurrence risk of venous thromboembolism (VTE) is uncertain. We performed a prospective cohort study of 839 patients with first unprovoked VTE. VTE recurrence risk is high, particularly in men with proximal thrombosis or pulmonary embolism. Sex and VTE site determine the recurrence risk and should be considered for patient counseling. SUMMARY: Background The long-term recurrence risk (ltRR) of venous thromboembolism (VTE) is uncertain. Objective To assess the ltRR of patients with first unprovoked VTE. Patients/methods Patients were classified into three categories: distal deep vein thrombosis (DVT), proximal DVT or pulmonary embolism (PE), that is, PE associated with DVT or isolated PE. Patients with major thrombophilia or antithrombotic therapy were excluded. The endpoint was recurrent symptomatic VTE. Results A total of 839 patients were followed for a median of 7.7 years. VTE recurred in 263 patients (31%). After 10 and 20 years, the cumulative ltRR was 32% (95% confidence interval [CI], 29-36) and 44% (95% CI, 38-49) with 3.9 (95% CI, 3.3-4.6) and 3.3 (95% CI, 2.7-4.0) events per 100 patient-years, respectively. The adjusted hazard ratio was 2.1 (95% CI, 1.4-3.2) and 2.1 (95% CI, 1.4-3.2) for patients with proximal DVT or PE compared with patients with distal DVT and was 2.1 (95% CI, 1.6-2.9) for men compared with women. At 10 years, 4.7 (95% CI, 3.8-5.8) events per 100 patient-years occurred in men with proximal DVT or PE, 2.4 (95% CI, 1.2-4.4) in men with distal DVT, 1.9 (95% CI, 1.2-2.8) in women with proximal DVT or PE and 0.9 (95% CI, 0.2-1.9) in women with distal DVT. Conclusion The ltRR of patients with first unprovoked VTE is high and dependent upon sex and VTE site.

Effects of P2Y12 receptor inhibition with or without aspirin on hemostatic system activation: a randomized trial in healthy subjects.

UNLABELLED: ESSENTIALS: In acute coronary syndromes, dual antiplatelet therapy inhibits platelets but confers a bleeding risk. Healthy male volunteers received clopidogrel or ticagrelor plus aspirin or clopidogrel or ticagrelor alone. The decrease in ß-thromboglobulin in shed blood was comparable after single and dual antiplatelet therapy. We hypothesize that patients with acute coronary syndromes may not require dual antiplatelet therapy. BACKGROUND: Dual antiplatelet therapy with a P2Y12 inhibitor and aspirin is standard in acute coronary syndromes. Dual antiplatelet therapy causes more bleeding than single antiplatelet therapy with a P2Y12 inhibitor. OBJECTIVES: To compare the effects of dual and single antiplatelet therapies on hemostatic system activation. PATIENTS/METHODS: In a randomized, parallel-group, double-blind, placebo-controlled study, 44 healthy volunteers received clopidogrel (600 mg, then 150 mg d(-1) ) and aspirin (100 mg d(-1) ) or placebo for 7 days; An additional 44 volunteers received single-dose ticagrelor (180 mg) and aspirin (300 mg) or placebo. ß-Thromboglobulin (ß-TG [IU L(-1) ]) and prothrombin fragment 1.2 (f1.2 [nmol L(-1) ]) were measured in blood obtained from bleeding time incisions. Data are given as geometric mean ratio (GMR [95% confidence interval]) to describe the differences in the first 2 h and as mean differences (Δ [95% confidence interval]) in area under the curve (AUC) to discriminate differences in effects over the total observation time. RESULTS: Clopidogrel plus aspirin and clopidogrel plus placebo reduced ß-TG by a GMR of 0.51 (0.42-0.63) and 0.54 (0.46-0.64) at 2 h. Ticagrelor plus aspirin and ticagrelor plus placebo decreased ß-TG by a GMR of 0.38 (0.26-0.57) and 0.47 (0.31-0.72). Ticagrelor plus aspirin and ticagrelor plus placebo reduced f1.2 by a GMR of 0.58 (0.45-0.75) and 0.55 (0.38-0.80); clopidogrel did not. Over 24 h, no difference in ß-TG occurred between clopidogrel plus aspirin and clopidogrel plus placebo (ΔAUC = -2.9 [-9.9 to 4.1]) or between ticagrelor plus aspirin and ticagrelor plus placebo (ΔAUC = -3.5 [-11.8 to 4.7]). No difference in f1.2 occurred between clopidogrel plus aspirin and clopidogrel plus placebo (ΔAUC = -4.2 [-10.2 to 1.8]) or between ticagrelor plus aspirin and ticagrelor plus placebo (ΔAUC = -3.6 [-10.9 to 3.7]). CONCLUSIONS: P2Y12 inhibitor monotherapy and dual antiplatelet therapy inhibit hemostatic system activation to a comparable extent.

Risk of recurrence after a first unprovoked venous thromboembolism: external validation of the Vienna Prediction Model with pooled individual patient data.

BACKGROUND: In order to stratify patients with a first unprovoked venous thromboembolism (VTE) according to their recurrence risk and to identify those who would actually benefit from indefinite anticoagulation, three prediction models have been developed so far; none of them has been yet externally validated. OBJECTIVE: To externally validate the Vienna Prediction Model (VPM), a prediction guide for estimating the recurrence risk after a first unprovoked VTE developed through Cox modeling and including sex, D-dimer and index VTE site as predictors. PATIENTS/METHODS: Nine hundred and four patients pooled from five prospective studies evaluating the prognostic value of D-dimer for VTE recurrence served as the validation cohort. The validity of the VPM in stratifying patients according to their relative recurrence risk (discrimination) and in predicting the absolute recurrence risk (calibration) was tested with survival analysis methods. RESULTS: The ability of the VPM to distinguish patients' risk for recurrent VTE in the validation cohort was at least as good as in the original cohort, with a calibration slope of 1.17 (95% confidence interval 0.71-1.64; P = 0.456 for the hypothesis of a significant difference from 1), and a c-statistic of 0.626 (vs. 0.651 in the original derivation cohort). The VPM absolute predictions in terms of cumulative rates tended to underestimate the observed recurrence rates at 12 months. CONCLUSIONS: By using a pooled individual patient database as a validation cohort, we confirmed the ability of the VPM to stratify patients with a first unprovoked VTE according to their risk of recurrence.

Antithrombotic triple therapy and coagulation activation at the site of thrombus formation: a randomized trial in healthy subjects.

BACKGROUND: Patients with acute coronary syndrome and concomitant atrial fibrillation may require antithrombotic triple therapy but clinical evidence of safety and efficacy is poor. We have therefore studied the combination of different antithrombotic medicines for coagulation activation in an in vivo model in the skin microvasculature. METHODS AND RESULTS: Platelet activation (ß-thromboglobulin [ß-TG]) and thrombin generation (prothrombin fragment 1 + 2 [F1+2 ], thrombin-antithrombin complex [TAT]) were studied in an open-label, randomized, parallel group trial in 60 healthy male subjects (n = 20 per group) who received ticagrelor and acetylsalicylic acid (ASA) in combination with dabigatran (150 mg bid), rivaroxaban (20 mg od) or phenprocoumon (INR 2.0-3.0). Coagulation biomarkers in shed blood were assessed at 3 h after monotherapy with the medicines under study, at 3 h after triple therapy dosing and at steady state trough conditions. Single doses of ticagrelor, dabigatran or rivaroxaban caused comparable decreases in shed blood ß-TG and were more pronounced than phenprocoumon at an INR of 2.0-3.0. In contrast, thrombin generation was more affected by rivaroxaban and phenprocoumon than by dabigatran. During triple therapy a similarly sustained inhibition of platelet activation and thrombin generation with a maximum decrease of ß-TG, F1+2 and TAT at 3 h post-dosing was noted, which remained below pre-dose levels at trough steady state. CONCLUSION: A triple therapy at steady state with ticagrelor plus ASA in combination with dabigatran or rivaroxaban is as effective as a combination with phenprocoumon for platelet activation and thrombin generation in vivo.

Oral anticoagulation and vitamin K deficiency.

A 61-year old woman with atrial fibrillation developed macrohaematuria during anticoagulant treatment with a direct oral factor Xa inhibitor for stroke prevention. Abnormal results of coagulation assays were first interpreted as an effect of the anticoagulant. However, upon further testing diagnosis of vitamin K deficiency was established. After vitamin K supplementation, coagulation tests normalized and macrohaematuria disappeared. Treatment with broad spectrum antibiotics for urinary tract infection was finally established as a rare cause for vitamin K deficiency in the patient.

The risk of recurrence in women with venous thromboembolism while using estrogens: a prospective cohort study.

BACKGROUND: The optimal duration of anticoagulation for women who had venous thromboembolism (VTE) associated with estrogen use is unknown. OBJECTIVES: To test the hypothesis that women who had a first VTE while using estrogens have a low risk of recurrence. METHODS: A Prospective cohort study of 630 women (333 estrogen users, 297 non-users) with a first VTE, who were followed for an average of 69 months after anticoagulation withdrawal. Women with a previous or secondary VTE, coagulation inhibitor deficiency, lupus anticoagulant, cancer, pregnancy, requirement of long-term antithrombotic therapy or homozygosity or double heterozygosity for factor V Leiden and/or the G20210A prothrombin mutation were excluded. The endpoint was objectively documented symptomatic recurrent VTE. RESULTS: VTE recurred in 22 (7%) estrogen users and in 49 (17%) non-users. After 1, 2 and 5 years, the cumulative probability of recurrence was 1% (95% confidence interval [CI], 0-2), 1% (95% CI, 0-2) and 6% (95% CI, 3-9) among estrogen users and 5% (95% CI, 2-7), 9% (95% CI, 6-13) and 17% (95% CI, 12-22) among non-users. Compared with non-users, estrogen users had an adjusted relative risk (RR) of recurrent VTE of 0.4 (95% CI, 0.2-0.8). Compared with non-users in the respective age groups, the RR of recurrence was 0.4 (95% CI, 0.2-0.8) among estrogen-containing-contraceptive users and 0.7 (95% CI, 0.3-1.5) among women using estrogen-containing menopausal hormone therapy. CONCLUSIONS: Women who had their first VTE while using estrogens have a low risk of recurrent VTE. These women might not benefit from extended anticoagulant therapy.

Anticoagulation after venous thromboembolism. Deciding on the optimal duration.

Deciding on the optimal duration of anticoagulation is based on the risk of recurrent venous thromboembolism (VTE) and of bleeding during anticoagulation. The duration of anticoagulation should be at least three months since shorter courses double the recurrence rates. At three months anticoagulation can be stopped in patients with a VTE provoked by a transient risk factor, as the recurrence risk is expected to be lower than the bleeding risk during anticoagulation. Patients with unprovoked VTE are at higher risk of recurrence and prolonged anticoagulation is currently recommended. However, attempts are made to stratify these patients according to their recurrence risk and to identify those with a low recurrence risk who would not benefit from extended anticoagulation. Novel approaches to optimize the management of patients with unprovoked VTE are the use of prediction models which link clinical patient characteristics with laboratory testing to discriminate between patients with a low risk (who may discontinue anticoagulation) and those with high risk (in whom long term anticoagulation is justified). Moreover, new antithrombotic concepts including new oral anticoagulants or aspirin both of which potentially confer a lower bleeding risk and are more convenient for the patients have been explored for extended thromboprophylaxis.

Predicting disease recurrence in patients with previous unprovoked venous thromboembolism: a proposed prediction score (DASH).

BACKGROUND: In patients with unprovoked venous thromboembolism (VTE), the optimal duration of anticoagulation is anchored on estimating the risk of disease recurrence. OBJECTIVES: We aimed to develop a score that could predict the recurrence risk following a first episode of unprovoked VTE, pooling individual patient data from seven prospective studies. METHODS: One thousand eight hundred and eighteen cases with unprovoked VTE treated for at least 3 months with a vitamin K antagonist were available for analysis. Optimism-corrected Cox regression coefficients were used to develop a recurrence score that was subsequently internally validated by bootstrap analysis. RESULTS: Abnormal D-dimer after stopping anticoagulation, age <50 years, male sex and VTE not associated with hormonal therapy (in women) were the main predictors of recurrence and were used to derive a prognostic recurrence score (DASH, D-dimer, Age, Sex, Hormonal therapy) showing a satisfactory predictive capability (ROC area =0.71). The annualized recurrence risk was 3.1% (95% confidence interval [CI], 2.3-3.9) for a score ≤ 1, 6.4% (95% CI, 4.8-7.9) for a score=2 and 12.3% (95% CI, 9.9-14.7) for a score ≥ 3. By considering at low recurrence risk those patients with a score ≤ 1, life-long anticoagulation might be avoided in about half of patients with unprovoked VTE. CONCLUSIONS: The DASH prediction rule appears to predict recurrence risk in patients with a first unprovoked VTE and may be useful to decide whether anticoagulant therapy should be continued indefinitely or stopped after an initial treatment period of at least 3 months.

Peri-operative management of antiplatelet therapy in patients with coronary artery disease: joint position paper by members of the working group on Perioperative Haemostasis of the Society on Thrombosis and Haemostasis Research (GTH), the working group on Perioperative Coagulation of the Austrian Society for Anesthesiology, Resuscitation and Intensive Care (ÖGARI) and the Working Group Thrombosis of the European Society for Cardiology (ESC).

An increasing number of patients suffering from cardiovascular disease, especially coronary artery disease (CAD), are treated with aspirin and/or clopidogrel for the prevention of major adverse events. Unfortunately, there are no specific, widely accepted recommendations for the perioperative management of patients receiving antiplatelet therapy. Therefore, members of the Perioperative Haemostasis Group of the Society on Thrombosis and Haemostasis Research (GTH), the Perioperative Coagulation Group of the Austrian Society for Anesthesiology, Reanimation and Intensive Care (ÖGARI) and the Working Group Thrombosis of the European Society of Cardiology (ESC) have created this consensus position paper to provide clear recommendations on the perioperative use of anti-platelet agents (specifically with semi-urgent and urgent surgery), strongly supporting a multidisciplinary approach to optimize the treatment of individual patients with coronary artery disease who need major cardiac and non-cardiac surgery. With planned surgery, drug eluting stents (DES) should not be used unless surgery can be delayed for ≥12 months after DES implantation. If surgery cannot be delayed, surgical revascularisation, bare-metal stents or pure balloon angioplasty should be considered. During ongoing antiplatelet therapy, elective surgery should be delayed for the recommended duration of treatment. In patients with semi-urgent surgery, the decision to prematurely stop one or both antiplatelet agents (at least 5 days pre-operatively) has to be taken after multidisciplinary consultation, evaluating the individual thrombotic and bleeding risk. Urgently needed surgery has to take place under full antiplatelet therapy despite the increased bleeding risk. A multidisciplinary approach for optimal antithrombotic and haemostatic patient management is thus mandatory.

Duration of anticoagulation after initial idiopathic venous thrombosis--the swinging pendulum: risk assessment to predict recurrence.

Despite considerable advances in the identification of new risk factors for VTE, predicting the risk of recurrence in an individual patient remains a challenge. The impact of many of these risk factors on the recurrence risk is moderate, while the relevance of others is unknown or is regarded controversial. The determination of some markers of thrombophilia either lacks standardization or is too elaborate for routine purposes. Many patients carry more than one risk factor and their combined effect is unknown. Use of global coagulation markers that encompass the effects of clotting and/or fibrinolytic defects may improve risk assessment. In a future step, prothrombotic coagulation alterations need to be integrated with clinical risk factors. Reproducible and simple scoring systems may improve stratification of patients according to their recurrence risk and optimize duration of anticoagulant therapy.

Mechanisms underlying acquired von Willebrand syndrome associated with an IgM paraprotein.

Acquired von Willebrand (vW) syndrome is a rare bleeding disorder which is frequently associated with immunological, malignant or cardiovascular disorders. The underlying pathomechanisms, particularly in patients with IgM monoclonal gammopathies, often remain unknown. We report a patient with indolent small B-cell lymphoma (immunocytoma) and plasmacytic differentiation with an IgM kappa paraprotein who was admitted with retroperitoneal haematoma. Medical history and coagulation testing were consistent with acquired vW syndrome. vW immunohistochemistry showed normal cytoplasmic labelling of endothelial cells and megakaryocytes, whereas the lymphomatous infiltrate was negative. Acquired vW syndrome due to adsorption of vW factor on malignant cells was thus excluded. In the multimeric analysis, all multimers were present similar to that in type 1 vW syndrome, but the triplet structures were blurred. The bands on serum immunofixation electrophoresis were also atypically broadened, which suggested complex formation between the IgM and vW factor. Immunoprecipitation studies showed that the 176-kDa proteolytic fragment of vW factor co-precipitated with the IgM paraprotein in the patient but not in the controls, suggesting a specific interaction between vW factor and the paraprotein in the patient. The patient required surgery and was successfully managed by chemotherapy consisting of rituximab and fludarabin as well as plasma exchange.

Thrombin generation in haemophilia A patients with factor VIII inhibitors after infusion of recombinant factor VIIa.

BACKGROUND: Development of factor VIII inhibitors is a serious complication in haemophilia A patients. Recombinant factor VIIa (rVIIa) is clinically effective, but its effects on haemostatic system need still to be fully elucidated. MATERIAL AND METHODS: In an open controlled study, we measured thrombin generation (peak thrombin) in venous blood and prothrombin fragment F1 + 2 (F1 + 2) and D-dimer in venous and in shed blood in five haemophilia A patients with inhibitors before and after rVIIa infusion. A total of five healthy individuals who did not receive rVIIa served as controls. RESULTS: At baseline, patients had lower mean (min-max) peak thrombin levels than controls [0.12 (0.0-0.6) vs. 186.9 (116.0-254.4) nM, P = 0.001]. After infusion, peak thrombin levels increased in average to 40.7 (28.3-51.6) nM, which translates into 80.2% (95% CI 65.4-88.6%) lower levels compared to that of controls. Mean (min-max) F1 + 2 levels in venous blood did not differ significantly between patients and controls [160.7 (89.8-331.3) vs. 160.8 (104.4-242.3) pmol L(-1)], but increased in average (min-max) by 39.4% (14.1-58.5%) after infusion. In blood emerging from incisions made to determine the bleeding (shed blood), F1 + 2 levels were lower in patients than controls [1383.3 (906.4-2044.6) vs. 2981.7 (1610.0-4539.6) pmol L(-1); P = 0.04], but were not affected by rVIIa; D-dimer levels were significantly higher in haemophiliacs than in controls and remained unchanged after infusion. CONCLUSIONS: Haemophilia A patients with factor VIII inhibitors have low thrombin generation. After rVIIa, the extent of coagulation activation as measured by levels of F1 + 2 is increased, but thrombin generation is restored to only 20%. Peak thrombin levels could reflect the effects of rVIIa on coagulation mechanisms, and their relevance with regard to the clinical coagulation defect of haemophilia A patients with factor VIII inhibitors might be evaluated.