Evaluation of risk stratification schemes for ischaemic stroke and bleeding in 182 678 patients with atrial fibrillation: the Swedish Atrial Fibrillation cohort study

The impact of some risk factors for stroke and bleeding, and the value of stroke and bleeding risk scores, in atrial fibrillation (AF), has been debated, as clinical trial cohorts have not adequately tested these. Our objective was to investigate risk factors for stroke and bleeding in AF, and application of the new CHA(2)DS(2)-VASc and HAS-BLED schemes for stroke and bleeding risk assessments, respectively

Rivaroxaban vs. vitamin K antagonists for cardioversion in atrial fibrillation

AIMS: X-VeRT is the first prospective randomized trial of a novel oral anticoagulant in patients with atrial fibrillation undergoing elective cardioversion.METHODS AND RESULTS: We assigned 1504 patients to rivaroxaban (20 mg once daily, 15 mg if creatinine clearance was between 30 and 49 mL/min) or dose-adjusted vitamin K antagonists (VKAs) in a 2:1 ratio. Investigators selected either an early (target period of 1-5 days after randomization) or delayed (3-8 weeks) cardioversion strategy. The primary efficacy outcome was the composite of stroke, transient ischaemic attack, peripheral embolism, myocardial infarction, and cardiovascular death. The primary safety outcome was major bleeding. The primary efficacy outcome occurred in 5 (two strokes) of 978 patients (0.51%) in the rivaroxaban group and in 5 (two strokes) of 492 patients (1.02%) in the VKA group [risk ratio 0.50; 95% confidence interval (CI) 0.15-1.73]. In the rivaroxaban group, four patients experienced primary efficacy events following early cardioversion (0.71%) and one following delayed cardioversion (0.24%). In the VKA group, three patients had primary efficacy events following early cardioversion (1.08%) and two following delayed cardioversion (0.93%). Rivaroxaban was associated with a significantly shorter time to cardioversion compared with VKAs (P &lt; 0.001). Major bleeding occurred in six patients (0.6%) in the rivaroxaban group and four patients (0.8%) in the VKA group (risk ratio 0.76; 95% CI 0.21-2.67).CONCLUSION: Oral rivaroxaban appears to be an effective and safe alternative to VKAs and may allow prompt cardioversion.NAME OF THE TRIAL REGISTRY: Clinicaltrials.gov;TRIAL REGISTRATION NUMBER: NCT01674647.</p

Apixaban compared with warfarin in patients with atrial fibrillation and previous stroke or transient ischaemic attack: a subgroup analysis of the ARISTOTLE trial.

Item does not contain fulltextBACKGROUND: In the ARISTOTLE trial, the rate of stroke or systemic embolism was reduced by apixaban compared with warfarin in patients with atrial fibrillation (AF). Patients with AF and previous stroke or transient ischaemic attack (TIA) have a high risk of stroke. We therefore aimed to assess the efficacy and safety of apixaban compared with warfarin in prespecified subgroups of patients with and without previous stroke or TIA. METHODS: Between Dec 19, 2006, and April 2, 2010, patients were enrolled in the ARISTOTLE trial at 1034 clinical sites in 39 countries. 18,201 patients with AF or atrial flutter were randomly assigned to receive apixaban 5 mg twice daily or warfarin (target international normalised ratio 2.0-3.0). The median duration of follow-up was 1.8 years (IQR 1.4-2.3). The primary efficacy outcome was stroke or systemic embolism, analysed by intention to treat. The primary safety outcome was major bleeding in the on-treatment population. All participants, investigators, and sponsors were masked to treatment assignments. In this subgroup analysis, we estimated event rates and used Cox models to compare outcomes in patients with and without previous stroke or TIA. The ARISTOTLE trial is registered with ClinicalTrials.gov, number NTC00412984. FINDINGS: Of the trial population, 3436 (19%) had a previous stroke or TIA. In the subgroup of patients with previous stroke or TIA, the rate of stroke or systemic embolism was 2.46 per 100 patient-years of follow-up in the apixaban group and 3.24 in the warfarin group (hazard ratio [HR] 0.76, 95% CI 0.56 to 1.03); in the subgroup of patients without previous stroke or TIA, the rate of stroke or systemic embolism was 1.01 per 100 patient-years of follow-up with apixaban and 1.23 with warfarin (HR 0.82, 95% CI 0.65 to 1.03; p for interaction=0.71). The absolute reduction in the rate of stroke and systemic embolism with apixaban versus warfarin was 0.77 per 100 patient-years of follow-up (95% CI -0.08 to 1.63) in patients with and 0.22 (-0.03 to 0.47) in those without previous stroke or TIA. The difference in major bleeding with apixaban compared with warfarin was 1.07 per 100 patient-years (95% CI 0.09-2.04) in patients with and 0.93 (0.54-1.32) in those without previous stroke or TIA. INTERPRETATION: The effects of apixaban versus warfarin were consistent in patients with AF with and without previous stroke or TIA. Owing to the higher risk of these outcomes in patients with previous stroke or TIA, the absolute benefits of apixaban might be greater in this population. FUNDING: Bristol-Myers Squibb and Pfizer.1 juni 201

Digoxin and Mortality in Patients With Atrial Fibrillation

BACKGROUND: Digoxin is widely used in patients with atrial fibrillation (AF). OBJECTIVES: The goal of this paper was to explore whether digoxin use was independently associated with increased mortality in patients with AF and if the association was modified by heart failure and/or serum digoxin concentration. METHODS: The association between digoxin use and mortality was assessed in 17,897 patients by using a propensity score-adjusted analysis and in new digoxin users during the trial versus propensity score-matched control participants. The authors investigated the independent association between serum digoxin concentration and mortality after multivariable adjustment. RESULTS: At baseline, 5,824 (32.5%) patients were receiving digoxin. Baseline digoxin use was not associated with an increased risk of death (adjusted hazard ratio [HR]: 1.09; 95% confidence interval [CI]: 0.96 to 1.23; p = 0.19). However, patients with a serum digoxin concentration ≥1.2 ng/ml had a 56% increased hazard of mortality (adjusted HR: 1.56; 95% CI: 1.20 to 2.04) compared with those not on digoxin. When analyzed as a continuous variable, serum digoxin concentration was associated with a 19% higher adjusted hazard of death for each 0.5-ng/ml increase (p = 0.0010); these results were similar for patients with and without heart failure. Compared with propensity score-matched control participants, the risk of death (adjusted HR: 1.78; 95% CI: 1.37 to 2.31) and sudden death (adjusted HR: 2.14; 95% CI: 1.11 to 4.12) was significantly higher in new digoxin users. CONCLUSIONS: In patients with AF taking digoxin, the risk of death was independently related to serum digoxin concentration and was highest in patients with concentrations ≥1.2 ng/ml. Initiating digoxin was independently associated with higher mortality in patients with AF, regardless of heart failure

Apixaban versus warfarin in patients with atrial fibrillation

Background: Vitamin K antagonists are highly effective in preventing stroke in patients with atrial fibrillation but have several limitations. Apixaban is a novel oral direct factor Xa inhibitor that has been shown to reduce the risk of stroke in a similar population in comparison with aspirin. Methods: In this randomized, double-blind trial, we compared apixaban (at a dose of 5 mg twice daily) with warfarin (target international normalized ratio, 2.0 to 3.0) in 18,201 patients with atrial fibrillation and at least one additional risk factor for stroke. The primary outcome was ischemic or hemorrhagic stroke or systemic embolism. The trial was designed to test for noninferiority, with key secondary objectives of testing for superiority with respect to the primary outcome and to the rates of major bleeding and death from any cause. Results: The median duration of follow-up was 1.8 years. The rate of the primary outcome was 1.27% per year in the apixaban group, as compared with 1.60% per year in the warfarin group (hazard ratio with apixaban, 0.79; 95% confidence interval [CI], 0.66 to 0.95; P&lt;0.001 for noninferiority; P=0.01 for superiority). The rate of major bleeding was 2.13% per year in the apixaban group, as compared with 3.09% per year in the warfarin group (hazard ratio, 0.69; 95% CI, 0.60 to 0.80; P&lt;0.001), and the rates of death from any cause were 3.52% and 3.94%, respectively (hazard ratio, 0.89; 95% CI, 0.80 to 0.99; P=0.047). The rate of hemorrhagic stroke was 0.24% per year in the apixaban group, as compared with 0.47% per year in the warfarin group (hazard ratio, 0.51; 95% CI, 0.35 to 0.75; P&lt;0.001), and the rate of ischemic or uncertain type of stroke was 0.97% per year in the apixaban group and 1.05% per year in the warfarin group (hazard ratio, 0.92; 95% CI, 0.74 to 1.13; P=0.42). Conclusions: In patients with atrial fibrillation, apixaban was superior to warfarin in preventing stroke or systemic embolism, caused less bleeding, and resulted in lower mortality

Apixaban compared with warfarin in patients with atrial fibrillation and previous stroke or transient ischaemic attack: A subgroup analysis of the ARISTOTLE trial

Background: In the ARISTOTLE trial, the rate of stroke or systemic embolism was reduced by apixaban compared with warfarin in patients with atrial fibrillation (AF). Patients with AF and previous stroke or transient ischaemic attack (TIA) have a high risk of stroke. We therefore aimed to assess the efficacy and safety of apixaban compared with warfarin in prespecified subgroups of patients with and without previous stroke or TIA. Methods: Between Dec 19, 2006, and April 2, 2010, patients were enrolled in the ARISTOTLE trial at 1034 clinical sites in 39 countries. 18 201 patients with AF or atrial flutter were randomly assigned to receive apixaban 5 mg twice daily or warfarin (target international normalised ratio 2·0-3·0). The median duration of follow-up was 1·8 years (IQR 1·4-2·3). The primary efficacy outcome was stroke or systemic embolism, analysed by intention to treat. The primary safety outcome was major bleeding in the on-treatment population. All participants, investigators, and sponsors were masked to treatment assignments. In this subgroup analysis, we estimated event rates and used Cox models to compare outcomes in patients with and without previous stroke or TIA. The ARISTOTLE trial is registered with ClinicalTrials.gov, number NTC00412984. Findings: Of the trial population, 3436 (19%) had a previous stroke or TIA. In the subgroup of patients with previous stroke or TIA, the rate of stroke or systemic embolism was 2·46 per 100 patient-years of follow-up in the apixaban group and 3·24 in the warfarin group (hazard ratio [HR] 0·76, 95% CI 0·56 to 1·03); in the subgroup of patients without previous stroke or TIA, the rate of stroke or systemic embolism was 1·01 per 100 patient-years of follow-up with apixaban and 1·23 with warfarin (HR 0·82, 95% CI 0·65 to 1·03; p for interaction=0·71). The absolute reduction in the rate of stroke and systemic embolism with apixaban versus warfarin was 0·77 per 100 patient-years of follow-up (95% CI -0·08 to 1·63) in patients with and 0·22 (-0·03 to 0·47) in those without previous stroke or TIA. The difference in major bleeding with apixaban compared with warfarin was 1·07 per 100 patient-years (95% CI 0·09-2·04) in patients with and 0·93 (0·54-1·32) in those without previous stroke or TIA. Interpretation: The effects of apixaban versus warfarin were consistent in patients with AF with and without previous stroke or TIA. Owing to the higher risk of these outcomes in patients with previous stroke or TIA, the absolute benefits of apixaban might be greater in this population. Funding: Bristol-Myers Squibb and Pfizer. © 2012 Elsevier Ltd

Apixaban versus warfarin in patients with atrial fibrillation

BACKGROUND: Vitamin K antagonists are highly effective in preventing stroke in patients with atrial fibrillation but have several limitations. Apixaban is a novel oral direct factor Xa inhibitor that has been shown to reduce the risk of stroke in a similar population in comparison with aspirin. METHODS: In this randomized, double-blind trial, we compared apixaban (at a dose of 5 mg twice daily) with warfarin (target international normalized ratio, 2.0 to 3.0) in 18,201 patients with atrial fibrillation and at least one additional risk factor for stroke. The primary outcome was ischemic or hemorrhagic stroke or systemic embolism. The trial was designed to test for noninferiority, with key secondary objectives of testing for superiority with respect to the primary outcome and to the rates of major bleeding and death from any cause. RESULTS: The median duration of follow-up was 1.8 years. The rate of the primary outcome was 1.27% per year in the apixaban group, as compared with 1.60% per year in the warfarin group (hazard ratio with apixaban, 0.79; 95% confidence interval [CI], 0.66 to 0.95; P<0.001 for noninferiority; P = 0.01 for superiority). The rate of major bleeding was 2.13% per year in the apixaban group, as compared with 3.09% per year in the warfarin group (hazard ratio, 0.69; 95% CI, 0.60 to 0.80; P<0.001), and the rates of death from any cause were 3.52% and 3.94%, respectively (hazard ratio, 0.89; 95% CI, 0.80 to 0.99; P = 0.047). The rate of hemorrhagic stroke was 0.24% per year in the apixaban group, as compared with 0.47% per year in the warfarin group (hazard ratio, 0.51; 95% CI, 0.35 to 0.75; P<0.001), and the rate of ischemic or uncertain type of stroke was 0.97% per year in the apixaban group and 1.05% per year in the warfarin group (hazard ratio, 0.92; 95% CI, 0.74 to 1.13; P = 0.42). CONCLUSIONS: In patients with atrial fibrillation, apixaban was superior to warfarin in preventing stroke or systemic embolism, caused less bleeding, and resulted in lower mortality. Copyright © 2011 Massachusetts Medical Society. All rights reserved