BackgroundAbout 20% of patients with unprovoked venous thromboembolism have a recurrence within 2 years after the withdrawal of oral anticoagulant therapy. Extending anticoagulation prevents recurrences but is associated with increased bleeding. The benefit of aspirin for the prevention of recurrent venous thromboembolism is unknown. MethodsIn this multicenter, investigator-initiated, double-blind study, patients with first-ever unprovoked venous thromboembolism who had completed 6 to 18 months of oral anticoagulant treatment were randomly assigned to aspirin, 100 mg daily, or placebo for 2 years, with the option of extending the study treatment. The primary efficacy outcome was recurrence of venous thromboembolism, and major bleeding was the primary safety outcome. ResultsVenous thromboembolism recurred in 28 of the 205 patients who received aspirin and in 43 of the 197 patients who received placebo (6.6% vs. 11.2% per year; hazard ratio, 0.58; 95% confidence interval [CI], 0.36 to 0.93) (median study period, 24.6 months). During a median treatment period of 23.9 months, 23 patients taking aspirin and 39 taking placebo had a recurrence (5.9% vs. 11.0% per year; hazard ratio, 0.55; 95% CI, 0.33 to 0.92). One patient in each treatment group had a major bleeding episode. Adverse events were similar in the two groups. ConclusionsAspirin reduced the risk of recurrence when given to patients with unprovoked venous thromboembolism who had discontinued anticoagulant treatment, with no apparent increase in the risk of major bleeding. (Funded by the University of Perugia and others; WARFASA ClinicalTrials.gov number, NCT00222677.)The New England Journal of Medicine Downloaded from nejm.org by SERGIO SIRAGUSA on June 23, 2012. For personal use only. No other uses without permission.

Summary. Background: Little information is available on the long-term clinical outcome of cerebral vein thrombosis (CVT). Objectives and methods:In an international, retrospective cohort study, we assessed the long-term rates of mortality, residual disability and recurrent venous thromboembolism (VTE) in a cohort of patients with a first CVT episode. Results: Seven hundred and six patients (73.7% females) with CVT were included. Patients were followed for a total of 3171 patient-years. Median follow-up was 40 months (range 6, 297 months). At the end of follow-up, 20 patients had died (2.8%). The outcome was generally good: 89.1% of patients had a complete recovery (modified Rankin Score [mRS] 0-1) and 3.8% had a partial recovery and were independent (mRS 2). Eighty-four per cent of patients were treated with oral anticoagulants and the mean treatment duration was 12 months. CVT recurred in 31 patients (4.4%), and 46 patients (6.5%) had a VTE in a different site, for an overall incidence of recurrence of 23.6 events per 1000 patient-years (95% confidence Interval [CI] 17.8, 28.7) and of 35.1 events/1000 patientyears (95% CI, 27.7, 44.4) after anticoagulant therapy withdrawal. A previous VTE was the only significant predictor of recurrence at multivariate analysis (hazard ratio [HR] 2.70; 95% CI 1.25, 5.83). Conclusions: The long-term risk of mortality and recurrent VTE appears to be low in patients who survived the acute phase of CVT. A previous VTE history independently predicts recurrent events.

BACKGROUNDThe prevalence of pulmonary embolism among patients hospitalized for syncope is not well documented, and current guidelines pay little attention to a diagnostic workup for pulmonary embolism in these patients. METHODSWe performed a systematic workup for pulmonary embolism in patients admitted to 11 hospitals in Italy for a first episode of syncope, regardless of whether there were alternative explanations for the syncope. The diagnosis of pulmonary embolism was ruled out in patients who had a low pretest clinical probability, which was defined according to the Wells score, in combination with a negative d-dimer assay. In all other patients, computed tomographic pulmonary angiography or ventilation-perfusion lung scanning was performed. RESULTSA total of 560 patients (mean age, 76 years) were included in the study. A diagnosis of pulmonary embolism was ruled out in 330 of the 560 patients (58.9%) on the basis of the combination of a low pretest clinical probability of pulmonary embolism and negative d-dimer assay. Among the remaining 230 patients, pulmonary embolism was identified in 97 (42.2%). In the entire cohort, the prevalence of pulmonary embolism was 17.3% (95% confidence interval, 14.2 to 20.5). Evidence of an embolus in a main pulmonary or lobar artery or evidence of perfusion defects larger than 25% of the total area of both lungs was found in 61 patients. Pulmonary embolism was identified in 45 of the 355 patients (12.7%) who had an alternative explanation for syncope and in 52 of the 205 patients (25.4%) who did not. CONCLUSIONSPulmonary embolism was identified in nearly one of every six patients hospitalized for a first episode of syncope. (Funded by the University of Padua; PESIT ClinicalTrials.gov number, NCT01797289.)

Background About 20% of patients with unprovoked venous thromboembolism have a recurrence within 2 years after the withdrawal of oral anticoagulant therapy. Extending anticoagulation prevents recurrences but is associated with increased bleeding. The benefit of aspirin for the prevention of recurrent venous thromboembolism is unknown. Methods In this multicenter, investigator-initiated, double-blind study, patients with first-ever unprovoked venous thromboembolism who had completed 6 to 18 months of oral anticoagulant treatment were randomly assigned to aspirin, 100 mg daily, or placebo for 2 years, with the option of extending the study treatment. The primary efficacy outcome was recurrence of venous thromboembolism, and major bleeding was the primary safety outcome. Results Venous thromboembolism recurred in 28 of the 205 patients who received aspirin and in 43 of the 197 patients who received placebo (6.6% vs. 11.2% per year; hazard ratio, 0.58; 95% confidence interval [CI], 0.36 to 0.93) (median study period, 24.6 months). During a median treatment period of 23.9 months, 23 patients taking aspirin and 39 taking placebo had a recurrence (5.9% vs. 11.0% per year; hazard ratio, 0.55; 95% CI, 0.33 to 0.92). One patient in each treatment group had a major bleeding episode. Adverse events were similar in the two groups. Conclusions Aspirin reduced the risk of recurrence when given to patients with unprovoked venous thromboembolism who had discontinued anticoagulant treatment, with no apparent increase in the risk of major bleeding. (Funded by the University of Perugia and others; WARFASA ClinicalTrials.gov number, NCT00222677.