Epidemiology of venous thromboembolism: the need for large (including prospective) studies and meta‐analyses

See also Rosendaal FR. Etiology of venous thrombosis: the need for small original studies. This issue, pp 2189–90 and El‐Galaly TC, Kristensen SR, Overvad K, Steffensen R, Tjønneland A, Severinsen MT. Interaction between blood type, smoking and factor V Leiden mutation and risk of venous thromboembolism: a Danish case–cohort study. This issue, pp 2191–3.     

Etiology of venous thrombosis: the need for small original studies

See also Lowe GDO. Epidemiology of venous thromboembolism: the need for large (including prospective) studies and meta‐analyses. This issue, pp 2186–8 and El‐Galaly TC, Kristensen SR, Overvad K, Steffensen R, Tjønneland A, Severinsen MT. Interaction between blood type, smoking and factor V Leiden mutation and risk of venous thromboembolism: a Danish case–cohort study. This issue, pp 2191–3.     

Fine particulate: it matters

See also Bonzini M, Tripodi A, Artoni A, Tarantini L, Marinelli B, Bertazzi PA, Apostoli P, Baccarelli A. Effects of inhalable particulate matter on blood coagulation. This issue, pp 662–8; Dales RE, Cakmak S, Vidal CB. Air pollution and hospitalization for venous thromboembolic disease in Chile. This issue, pp 669–74.     

Unmasking Asian thrombophilia: is APC dysfunction the real culprit?

See also Tang L, Lu X, Yu JM, Wang QY, Yang R, Guo T, Mei H, Hu Y. PROC c.574_576del polymorphism: a common genetic risk factor for venous thrombosis in the Chinese population. This issue, pp 2019–26.     

New oral antithrombotics: a need for laboratory monitoring. Against

See also Mismetti P, Laporte S. New oral antithrombotics: a need for laboratory monitoring. For. This issue, pp 621–6.     

New oral antithrombotics: a need for laboratory monitoring. For

See also Bounameaux H, Reber G. New oral antithrombotics: a need for laboratory monitoring. Against. This issue, pp 627–30.     

RVO – Real value obscure

See also Carrier M, Rodger MA, Wells PS, Righini M, Le Gal G. Residual vein obstruction to predict the risk of recurrent venous thromboembolism in patients with deep vein thrombosis: a systematic review and meta‐analysis. This issue, pp 1119–25; Le Gal G, Carrier M, Kovacs MJ, Betancourt MT, Kahn SR, Wells PS, Anderson DA, Chagnon I, Solymoss S, Crowther M, Righini M, Delluc A, White RH, Vickars L, Rodger M. Residual vein obstruction as a predictor for recurrent thromboembolic events after a first unprovoked episode: data from the REVERSE cohort study. This issue, pp 1126–32.     

Best evidence on B‐domain deletion and the immunogenicity of recombinant factor VIII

See also Aledort LM, Navickis RJ, Wilkes MM. Can B‐domain deletion alter the immunogenicity of recombinant factor VIII? A meta‐analysis of prospective clinical studies. This issue, pp 2180–92; Mannucci PM. Factor VIII inhibitors in previously treated hemophilic patients. This issue, pp 2328–9.     

More on: calibration for the measurement of microparticles: needs,interests, and limitations of calibrated polystyrene beads for flow cytometry‐based quantification of biological microparticles

See also Chandler WL, Yeung W, Tait JF. A new microparticle size calibration standard for use in measuring smaller microparticles using a new flow cytometer. J Thromb Haemost 2011; 9: 1216–24; Robert S, Poncelet P, Lacroix R, Raoult D, Dignat‐George F. More on: calibration for the measurement of microparticles: value of calibrated polystyrene beads for flow cytometry‐based sizing of biological microparticles. This issue, pp 1676–8; Chandler WL, Yeung W, Tait JF. More on: calibration for the measurement of microparticles: the authors respond. This issue, pp 1681–2.     

DIC score predicts mortality in massive clot coagulopathy as a result of extensive pulmonary embolism: reply to a rebuttal

See also Levi M. Disseminated intravascular coagulation or extended intravascular coagulation in massive pulmonary embolism. This issue, pp 1475–6; Leitner JM, Jilma B, Spiel AO, Sterz F, Laggner AN, Janata KM. Massive pulmonary embolism leading to cardiac arrest is associated with consumptive coagulopathy presenting as disseminated intravascular coagulation. This issue, pp 1477–82; Thachil J. DIC score predicts mortality in massive clot coagulopathy as a result of extensive pulmonary embolism: a rebuttal. This issue, pp 1657–8.     

More on: calibration for the measurement of microparticles: value of calibrated polystyrene beads for flow cytometry‐based sizing of biological microparticles

See also Chandler WL, Yeung W, Tait JF. A new microparticle size calibration standard for use in measuring smaller microparticles using a new flow cytometer. J Thromb Haemost 2011; 9: 1216–24; Mullier F, Bailly N, Chatelain C, Dogné JM, Chatelain B. More on: calibration for the measurement of microparticles: needs, interests, and limitations of calibrated polystyrene beads for flow cytometry‐based quantification of biological microparticles. This issue, pp 1679–81; Chandler WL, Yeung W, Tait JF. More on: calibration for the measurement of microparticles: the authors respond. This issue, pp 1681–2.     

Residual vein obstruction as a predictor for recurrent thromboembolic events after a first unprovoked episode: data from the REVERSE cohort study

See also Watson HG. RVO – Real value obscure. This issue, pp 1116–8; Carrier M, Rodger MA, Wells PS, Righini M, Le Gal G. Residual vein obstruction to predict the risk of recurrent venous thromboembolism in patients with deep vein thrombosis: a systematic review and meta‐analysis. This issue, pp 1119–25. Summary. Objectives: There is growing interest in using residual vein obstruction (RVO) to guide the duration of oral anticoagulant therapy (OAT) for unprovoked deep vein thrombosis (DVT). We sought to determine if RVO as determined by compression ultrasonography (CUS) after completion of 5–7 months of anticoagulation for unprovoked DVT is associated with an increased risk of recurrent venous thromboembolism (VTE). Materials and Methods: This was a multicentre multinational prospective cohort study undertaken in tertiary care centers. Patients with a first ‘unprovoked’ major VTE were enrolled over a 4‐year period and completed a mean 18‐month follow‐up in September 2006. All 452 patients with DVT had baseline CUS at inclusion to assess any RVO before stopping OAT at 5–7 months. During follow‐up off OAT, all episodes of suspected recurrent VTE were independently adjudicated with reference to baseline imaging. Results: Forty‐five out of 231 patients with abnormal CUS (19.5%) had recurrent VTE during follow‐up, as compared with 32 out of 220 patients with normal CUS (14.6%), and one patient had inadequate CUS. There was no significant association between an abnormal CUS at inclusion and the risk of recurrent VTE: hazard ratio 1.4 (95% confidence interval, 0.9–2.1), P = 0.19. None of the different degrees of clot resolution on baseline CUS was statistically significantly associated with the risk of recurrent VTE. Conclusion: In our study, the presence of RVO at the time of OAT withdrawal was not associated with a statistically significant higher risk of recurrent VTE. RVO assessment may not be useful to guide duration of anticoagulation.     

Residual vein obstruction to predict the risk of recurrent venous thromboembolism in patients with deep vein thrombosis: a systematic review and meta‐analysis

See also Watson HG. RVO – Real value obscure. This issue, pp 1116–8; Le Gal G, Carrier M, Kovacs MJ, Betancourt MT, Kahn SR, Wells PS, Anderson DA, Chagnon I, Solymoss S, Crowther M, Righini M, Delluc A, White RH, Vickars L, Rodger M. Residual vein obstruction as a predictor for recurrent thromboembolic events after a first unprovoked episode: data from the REVERSE cohort study. This issue, pp 1126–32. Summary. Background: Residual vein obstruction (RVO) detected on compression ultrasonography of the leg after a few months of anticoagulation therapy might be able to identify patients with deep vein thrombosis (DVT) at high risk of having a recurrent venous thromboembolism (VTE). Aim: To determine whether RVO is associated with an increased risk of recurrent events in patients with DVT. Patients and Methods: A systematic literature search strategy was conducted using MEDLINE, EMBASE, and the Cochrane Register of Controlled Trials. We selected 14 articles (nine prospective cohort studies and five randomized controlled trials) that included patients with DVT who had an assessment for RVO with the use of compression ultrasonography. Two reviewers independently extracted data onto standardized forms. Results: Overall, the presence of RVO was not associated with an increased risk of recurrent VTE (odds ratio [OR] 1.24, 95% confidence interval [CI] 0.9–1.7) in patients with unprovoked DVT who stopped oral anticoagulation therapy at the time of RVO assessment. However, RVO was significantly associated with recurrent VTE in patients with any (unprovoked or provoked) DVT (OR 1.5, 95% CI 1.1–2.0). Conclusions: RVO was associated with a modestly increased risk of recurrent VTE in patients with DVT (unprovoked and provoked). However, RVO did not seem to be a predictor of recurrent VTE in patients with unprovoked DVT following anticoagulation discontinuation. Further prospective studies are needed to assess the role of RVO in patients with unprovoked DVT.     

Fondaparinux in acute heparin‐induced thrombocytopenia: a case series

See also Greinacher A. Immunogenic but effective: the HIT‐fondaparinux brain puzzler. This issue, pp 2386–8; Warkentin TE, Pai M, Sheppard JI, Schulman S, Spyropoulos AC, Eikelboom JW. Fondaparinux treatment of acute heparin‐induced thrombocytopenia: confirmed by the serotonin‐release assay: a 30‐month, 16‐patient case series. This issue, pp 2389–96.     

Air pollution and hospitalization for venous thromboembolic disease in Chile

See also Mannucci PM. Fine particulate: it matters. This issue, pp 659–61; Bonzini M, Tripodi A, Artoni A, Tarantini L, Marinelli B, Bertazzi PA, Apostoli P, Baccarelli A. Effects of inhalable particulate matter on blood coagulation. This issue, pp 662–8. Summary. Background: Ambient air pollution is a risk factor for stroke and myocardial infarction, possibly because of alterations in coagulation that influence the arterial circulation. Whether air pollution influences diseases associated with peripheral venous thrombogenesis remains largely unknown. Objectives: To determine the association between air pollution and venous thromboembolic disease (VTE) in a sample of the general population. Methods: A time‐series analysis was used to test the association between daily air pollution and VTE hospitalizations in Santiago between 2001 and 2005. Results were adjusted for long‐term trends, day of the week and average daily humidex. Results: From a population of 5.4 million, there were, on average, 2.3 admissions for VTE per day. Pooled estimates of relative risk (RR) [95% confidence interval (CI)] of hospitalization for venous disease were: 1.07 (1.05, 1.09) for a 58.4 p.p.b. increase in ozone (O₃); 1.06 (1.02, 1.09) for a 5.85 p.p.b. increase in sulphur dioxide (SO₂); 1.08 (1.03, 1.12) for a 29.25 μg/m³ increase in nitrogen dioxide (NO₂); and 1.05 (1.03, 1.06) for a 20.02 μg/m³ increase in particulate matter ≤ 2.5 μm in mean aerodynamic diameter (PM_2.5). For pulmonary embolism (PE) results were: 1.10 (1.07, 1.13) for O₃; 1.05 (1.02, 1.08) for SO₂; 1.07 (1.04, 1.09) for NO₂; and 1.05(1.03, 1.06) for PM_2.5, respectively. Conclusion: Air pollution appears to be a risk factor for venous thrombosis and PE, a disease with a significant fatality rate.     

Disseminated intravascular coagulation or extended intravascular coagulation in massive pulmonary embolism

See also Leitner JM, Jilma B, Spiel AO, Sterz F, Laggner AN, Janata KM. Massive pulmonary embolism leading to cardiac arrest is associated with consumptive coagulopathy presenting as disseminated intravascular coagulation. This issue, pp 1477–82; Thachil J. DIC score predicts mortality in massive clot coagulopathy as a result of extensive pulmonary embolism: a rebuttal. This issue, pp 1657–8; Leitner JM, Janata‐Schwatzek K, Spiel AO, Sterz F, Laggner AN, Jilma B. DIC score predicts mortality in massive clot coagulopathy as a result of extensive pulmonary embolism: reply to a rebuttal. This issue, pp 1658–9.     

Strength and failure of fibrin fiber branchpoints

See also Weisel JW. Biomechanics in hemostasis and thrombosis. This issue, pp 1027–9; Liu W, Carlisle CR, Sparks EA, Guthold M. The mechanical properties of single fibrin fibers. This issue, pp 1030–6.     

Immunogenic but effective: the HIT‐fondaparinux brain puzzler

See also Warkentin TE, Pai M, Sheppard JI, Schulman S, Spyropoulos AC, Eikelboom JW. Fondaparinux treatment of acute heparininduced thrombocytopenia confirmed by the serotonin‐release assay: a 30‐month, 16‐patient case series. This issue, pp 2389–96; Goldfarb MJ, Blostein MD. Fondaparinux in acute heparin‐induced thrombocytopenia: a case series. This issue, pp 2501–3.     

Thrombophilia screening or screaming

See also Mahmoodi BK, Brouwer J‐LP, ten Kate MK, Lijfering WM, Veeger NJGM, Mulder AB, Kluin‐Nelemans HC, van der Meer J. A prospective cohort study on the absolute risks of venous thromboembolism and predictive value of screening asymptomatic relatives of patients with hereditary deficiencies of protein S, protein C or antithrombin. This issue, pp 1193–200.     

More on: calibration for the measurement of microparticles: the authors respond

See also Chandler WL, Yeung W, Tait JF. A new microparticle size calibration standard for use in measuring smaller microparticles using a new flow cytometer. J Thromb Haemost 2011; 9: 1216–24; Robert S, Poncelet P, Lacroix R, Raoult D, Dignat‐George F. More on: calibration for the measurement of microparticles: value of calibrated polystyrene beads for flow cytometry‐based sizing of biological microparticles. This issue, pp 1676–8; Mullier F, Bailly N, Chatelain C, Dogné JM, Chatelain B. More on: calibration for the measurement of microparticles: needs, interests, and limitations of calibrated polystyrene beads for flow cytometry‐based quantification of biological microparticles. This issue, pp 1679–81.DOI: 10.1111/j.1538‐7836.2011.04384.x .