Predictors of Recurrent Stroke After Embolic Stroke of Undetermined Source in the RE-SPECT ESUS Trial.

Background We sought to determine recurrent stroke predictors among patients with embolic strokes of undetermined source (ESUS). Methods and Results We applied Cox proportional hazards models to identify clinical features associated with recurrent stroke among participants enrolled in RE-SPECT ESUS (Randomized, Double-Blind, Evaluation in Secondary Stroke Prevention Comparing the Efficacy and Safety of the Oral Thrombin Inhibitor Dabigatran Etexilate Versus Acetylsalicylic Acid in Patients With Embolic Stroke of Undetermined Source) trial, an international clinical trial evaluating dabigatran versus aspirin for patients with ESUS. During a median follow-up of 19 months, 384 of 5390 participants had recurrent stroke (annual rate, 4.5%). Multivariable models revealed that stroke or transient ischemic attack before the index event (hazard ratio [HR], 2.27 [95% CI, 1.83-2.82]), creatinine clearance <50 mL/min (HR, 1.69 [95% CI, 1.23-2.32]), male sex (HR, 1.60 [95% CI, 1.27-2.02]), and CHA2DS2-VASc ≥4 (HR, 1.55 [95% CI, 1.15-2.08] and HR, 1.66 [95% CI, 1.21-2.26] for scores of 4 and ≥5, respectively) versus CHA2DS2-VASc of 2 to 3, were independent predictors for recurrent stroke. Conclusions In RE-SPECT ESUS trial, expected risk factors previously linked to other common stroke causes were associated with stroke recurrence. These data help define high-risk groups for subsequent stroke that may be useful for clinicians and for researchers designing trials among patients with ESUS. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02239120.

Predictors of Atrial Fibrillation Development in Patients With Embolic Stroke of Undetermined Source: An Analysis of the RE-SPECT ESUS Trial.

BACKGROUND: A proportion of patients with embolic stroke of undetermined source have silent atrial fibrillation (AF) or develop AF after the initial evaluation. Better understanding of the risk for development of AF is critical to implement optimal monitoring strategies with the goal of preventing recurrent stroke attributable to underlying AF. The RE-SPECT ESUS trial (Randomized, Double-Blind Evaluation in Secondary Stroke Prevention Comparing the Efficacy and Safety of the Oral Thrombin Inhibitor Dabigatran Etexilate Versus Acetylsalicylic Acid in Patients With Embolic Stroke of Undetermined Source) provides an opportunity to assess predictors for developing AF and associated recurrent stroke. METHODS: RE-SPECT ESUS was a randomized, controlled trial (564 sites, 42 countries) assessing dabigatran versus aspirin for the prevention of recurrent stroke in patients with embolic stroke of undetermined source. Of 5390 patients enrolled and followed for a median of 19 months, 403 (7.5%) were found to develop AF reported as an adverse event or using cardiac monitoring per standard clinical care. Univariable and multivariable regression analyses were performed to define predictors of AF. RESULTS: In the multivariable model, older age (odds ratio for 10-year increase, 1.99 [95% CI, 1.78-2.23]; P<0.001), hypertension (odds ratio, 1.36 [95% CI, 1.03-1.79]; P=0.0304), diabetes (odds ratio, 0.74 [95% CI, 0.56-0.96]; P=0.022), and body mass index (odds ratio for 5-U increase, 1.29 [95% CI, 1.16-1.43]; P<0.001) were independent predictors of AF during the study. In a sensitivity analysis restricted to 1117 patients with baseline NT-proBNP (N-terminal prohormone of brain natriuretic peptide) measurements, only older age and higher NT-proBNP were significant independent predictors of AF. Performance of several published predictive models was assessed, including HAVOC (AF risk score based on hypertension, age ≥75 years, valvular heart disease, peripheral vascular disease, obesity, congestive heart failure, and coronary artery disease) and CHA2DS2-VASc (stroke risk score based on congestive heart failure, hypertension, age ≥75 years [doubled], diabetes, previous stroke, transient ischemic attack or thromboembolism [doubled], vascular disease, age 65 to 74 years, and sex category [female]) scores, and higher scores were associated with higher rates of developing AF. CONCLUSIONS: Besides age, the most important variable, several other factors, including hypertension, higher body mass index, and lack of diabetes, are independent predictors of AF after embolic stroke of undetermined source. When baseline NT-proBNP was available, only older age and elevation of this biomarker were predictive of subsequent AF. Understanding who is at higher risk of developing AF will assist in identifying patients who may benefit from more intense, long-term cardiac monitoring. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02239120.

Evaluation of Dual Versus Triple Therapy by Landmark Analysis in the RE-DUAL PCI Trial.

OBJECTIVES: The aim of this study was to explore the early versus late benefits and risks of dabigatran dual therapy versus warfarin triple therapy in the RE-DUAL PCI (Randomized Evaluation of Dual Antithrombotic Therapy With Dabigatran Versus Triple Therapy With Warfarin in Patients With Nonvalvular Atrial Fibrillation Undergoing Percutaneous Coronary Intervention) trial. BACKGROUND: Patients with atrial fibrillation who undergo percutaneous coronary intervention are at increased risk for both bleeding and thrombotic events. METHODS: A total of 2,725 patients with atrial fibrillation underwent percutaneous coronary intervention and were randomized to receive dabigatran 110 mg, or dabigatran 150 mg plus a P2Y12 inhibitor (and no aspirin), or warfarin plus a P2Y12 inhibitor plus aspirin. Landmark analysis was performed at 30 and 90 days. RESULTS: There was a consistent and large reduction in major or clinically relevant nonmajor bleeding in patients randomized to dual therapy during the first 30 days (110 mg: hazard ratio [HR]: 0.45; 95% confidence interval [CI]: 0.31 to 0.66; p < 0.0001; 150 mg: HR: 0.46; 95% CI: 0.30 to 0.72; p = 0.0006) compared with warfarin triple therapy. There was early net clinical benefit in both dabigatran groups versus warfarin (110 mg: HR: 0.65; 95% CI: 0.47 to 0.88; p = 0.0062; 150 mg: HR: 0.54; 95% CI: 0.37 to 0.79; p = 0.0015), due to larger reductions in bleeding than increased thrombotic events for dabigatran 110 mg and bleeding reduction without increased thrombotic risk for dabigatran 150 mg dual therapy versus warfarin triple therapy. After the removal of aspirin in the warfarin group, bleeding remained lower with dabigatran 110 mg and was similar with dabigatran 150 mg versus warfarin. CONCLUSIONS: In RE-DUAL PCI, in which patients in the dual-therapy arms were treated with aspirin for an average of only 1.6 days, there was early net clinical benefit with both doses of dabigatran dual therapy, without an increase in thrombotic events with dabigatran 150 mg. This could be helpful in the subset of patients with elevated risk for both bleeding and thrombotic events.

Dabigatran or Aspirin After Embolic Stroke of Undetermined Source in Patients With Patent Foramen Ovale: Results From RE-SPECT ESUS.

BACKGROUND AND PURPOSE: Patent foramen ovale (PFO) may increase the risk of embolic stroke of undetermined source (ESUS). Guidelines suggest anticoagulation may be more effective than antiplatelets in preventing stroke in patients with ESUS and PFO when interventional closure is not performed. METHODS: Patients with ESUS randomized to dabigatran (150/110 mg BID) or aspirin (100 mg QD) from the RE-SPECT ESUS study (Randomized, Double-Blind, Evaluation in Secondary Stroke Prevention Comparing the Efficacy and Safety of the Oral Thrombin Inhibitor Dabigatran Etexilate Versus Acetylsalicylic Acid in Patients With Embolic Stroke of Undetermined Source) were included. The rate of recurrent stroke (primary end point) and ischemic stroke was reported for patients with and without baseline PFO. A meta-analysis comparing the effects of anticoagulant and antiplatelet therapy on ischemic stroke in patients with PFO was updated to include RE-SPECT ESUS. RESULTS: PFO was present in 680 of 5388 (12.6%) patients with documented PFO status. The risk of recurrent stroke with dabigatran versus aspirin was similar in patients with and without PFO (P for interaction, 0.8290). In patients with PFO, the meta-analysis found no statistically significant difference between anticoagulant and antiplatelet therapy (odds ratio, 0.70 [95% CI, 0.43-1.14]) for ischemic stroke. CONCLUSIONS: There is insufficient evidence to recommend anticoagulation over antiplatelet therapy for patients with ESUS and a PFO. More data are needed to guide antithrombotic therapy in this population. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT02239120.

Antithrombotic Treatment of Embolic Stroke of Undetermined Source: RE-SPECT ESUS Elderly and Renally Impaired Subgroups.

Background and Purpose- The RE-SPECT ESUS trial (Randomized, Double-Blind, Evaluation in Secondary Stroke Prevention Comparing the Efficacy and Safety of the Oral Thrombin Inhibitor Dabigatran Etexilate Versus Acetylsalicylic Acid in Patients With Embolic Stroke of Undetermined Source) tested the hypothesis that dabigatran would be superior to aspirin for the prevention of recurrent stroke in patients with embolic stroke of undetermined source. This exploratory subgroup analysis investigates the impact of age, renal function (both predefined), and dabigatran dose (post hoc) on the rates of recurrent stroke and major bleeding. Methods- RE-SPECT ESUS was a multicenter, randomized, double-blind trial of dabigatran 150 or 110 mg (for patients aged ≥75 years and/or with creatinine clearance 30 to <50 mL/minute) twice daily compared with aspirin 100 mg once daily. The primary outcome was recurrent stroke. Results- The trial, which enrolled 5390 patients from December 2014 to January 2018, did not demonstrate superiority of dabigatran versus aspirin for prevention of recurrent stroke in patients with embolic stroke of undetermined source. However, among the population qualifying for the lower dabigatran dose, the rate of recurrent stroke was reduced with dabigatran versus aspirin (7.4% versus 13.0%; hazard ratio, 0.57 [95% CI, 0.39-0.82]; interaction P=0.01). This was driven mainly by the subgroup aged ≥75 years (7.8% versus 12.4%; hazard ratio, 0.63 [95% CI, 0.43-0.94]; interaction P=0.10). Stroke rates tended to be lower with dabigatran versus aspirin with declining renal function. Risks for major bleeding were similar between treatments, irrespective of renal function, but with a trend for lower bleeding rates with dabigatran versus aspirin in older patients. Conclusions- In subgroup analyses of RE-SPECT ESUS, dabigatran reduced the rate of recurrent stroke compared with aspirin in patients qualifying for the lower dose of dabigatran. These results are hypothesis-generating. Aspirin remains the standard antithrombotic treatment for patients with embolic stroke of undetermined source. Registration- URL: https://www.clinicaltrials.gov; Unique identifier: NCT02239120.

Comparison of Dabigatran Plus a P2Y12 Inhibitor With Warfarin-Based Triple Therapy Across Body Mass Index in RE-DUAL PCI.

BACKGROUND: Body mass index (BMI) affects drug levels of nonvitamin K antagonist oral anticoagulants. We sought to assess whether BMI affected outcomes in the RE-DUAL PCI trial. METHODS: RE-DUAL PCI (NCT02164864) evaluated the safety and efficacy of a dual-antithrombotic-therapy regimen using dabigatran (110 mg or 150 mg twice daily and a P2Y12 platelet antagonist) in comparison with triple therapy of warfarin, aspirin, and a P2Y12 platelet inhibitor in 2725 patients with atrial fibrillation who had undergone percutaneous coronary intervention (PCI). We compared the risk of first International Society on Thrombosis and Haemostasis (ISTH)-defined major or clinically relevant nonmajor bleeding events (primary endpoint) and the composite of death, myocardial infarction, stroke, systemic embolism, or unplanned revascularization (main efficacy endpoint) in relation to baseline BMI. RESULTS: Median (range) BMI was 28.1 (14-66) kg/m2. Dabigatran dual therapy versus warfarin triple therapy had relevantly and similarly lower rates of bleeding at both 110 mg and 150 mg twice-daily doses, irrespective of BMI. Thromboembolic event rates appeared consistent across categories of BMI, including those <25 and ≥35 kg/m2 (P for interaction: 0.806 and 0.279, respectively). CONCLUSIONS: The reduction in bleeding with dabigatran dual therapy compared with warfarin triple therapy in patients here evaluated appears consistent across BMI categories.

Switching of Oral Anticoagulation Therapy After PCI in Patients With Atrial Fibrillation: The RE-DUAL PCI Trial Subanalysis.

OBJECTIVES: The aim of this study was to assess if prior oral anticoagulant agent (OAC) use modifies the lower bleeding risk observed with dabigatran dual therapy (dabigatran twice daily plus a P2Y12 inhibitor) versus warfarin triple therapy (warfarin plus a P2Y12 inhibitor plus aspirin) in patients with atrial fibrillation who underwent percutaneous coronary intervention (PCI). BACKGROUND: In the RE-DUAL PCI (Randomized Evaluation of Dual Antithrombotic Therapy With Dabigatran Versus Triple Therapy With Warfarin in Patients With Nonvalvular Atrial Fibrillation Undergoing Percutaneous Coronary Intervention) trial, the primary outcome of major bleeding or clinically relevant nonmajor bleeding was lower with dabigatran dual therapy versus warfarin triple therapy in patients with atrial fibrillation who underwent PCI. METHODS: A total of 2,725 patients were randomized to dual therapy with dabigatran (110 or 150 mg twice daily) plus clopidogrel or ticagrelor or triple therapy with warfarin plus aspirin and clopidogrel or ticagrelor. Subgroup analysis compared risk for major bleeding or clinically relevant nonmajor bleeding and a composite thromboembolic endpoint in patients with prior OAC use and in those who were OAC treatment naive. RESULTS: Risk for major bleeding or clinically relevant nonmajor bleeding was reduced with both dabigatran dual therapies compared with warfarin triple therapy in both the prior OAC use group (hazard ratios: 0.58 [95% confidence interval (CI): 0.42 to 0.81] and 0.61 [95% CI: 0.41 to 0.92] with 110 and 150 mg dabigatran, respectively) and the OAC-naive group (hazard ratios: 0.49 [95% CI: 0.38 to 0.63] and 0.76 [95% CI: 0.59 to 0.97] with 110 and 150 mg dabigatran) (p for interaction = 0.42 and 0.37, 110 and 150 mg dabigatran, respectively). The risk for thromboembolic events seemed similar with dabigatran dual therapy (both doses) and warfarin triple therapy across subgroups. CONCLUSIONS: Bleeding risk was reduced with dabigatran dual therapy versus warfarin triple therapy in patients with atrial fibrillation after PCI, regardless of whether they were prior OAC users or OAC treatment naive. These results suggest that it is also safe to switch patients on OAC pre-PCI to dabigatran dual therapy post-PCI.

Renal Function and Outcomes With Dabigatran Dual Antithrombotic Therapy in Atrial Fibrillation Patients After PCI.

OBJECTIVES: The study sought to evaluate the effect of dabigatran dual therapy versus warfarin triple therapy across categories of renal function in the RE-DUAL PCI (Randomized Evaluation of Dual Antithrombotic Therapy with Dabigatran versus Triple Therapy with Warfarin in Patients with Nonvalvular Atrial Fibrillation Undergoing Percutaneous Coronary Intervention) trial. BACKGROUND: The RE-DUAL PCI (NCT02164864) trial of patients with atrial fibrillation undergoing percutaneous coronary intervention reported that dabigatran dual therapy (110 or 150 mg twice daily, plus clopidogrel or ticagrelor) reduced the primary endpoint of major bleeding events (MBE) or clinically relevant nonmajor bleeding events (CRNMBE) compared with warfarin triple therapy, with noninferiority in overall thromboembolic events. METHODS: Risk of a first MBE or CRNMBE and the composite of death or thromboembolic event (DTE) or unplanned revascularization were evaluated in 2,725 patients according to baseline creatinine clearance (CrCl) categories: 30 to <50, 50 to <80, and ≥80 ml/min. RESULTS: Compared with warfarin, dabigatran 110 mg dual therapy reduced risk of MBE or CRNMBE across all categories of CrCl (p for interaction = 0.19). Dabigatran 150 mg dual therapy reduced risk of MBE or CRNMBE regardless of the CrCl category (p for interaction = 0.31). Risk of DTE or unplanned revascularization was similar to warfarin triple therapy for dabigatran 110 mg dual therapy across all CrCl categories. Dabigatran 150 mg dual therapy versus warfarin triple therapy had similar risk for DTE or unplanned revascularization in patients with CrCl 30 to <80 ml/min and lower risk at CrCl ≥80 ml/min (p for interaction = 0.02). CONCLUSIONS: In the RE-DUAL PCI trial, dabigatran dual therapy reduced bleeding events versus warfarin triple therapy irrespective of renal function, with overall similar risks of thromboembolic events but lower risks with dabigatran 150 mg in patients with normal CrCl.

Heparin dosing in uninterrupted anticoagulation with dabigatran vs. warfarin in atrial fibrillation ablation: RE-CIRCUIT study.

AIMS: To describe heparin dosing requirements in patients who underwent catheter ablation of atrial fibrillation with uninterrupted anticoagulation using dabigatran etexilate (dabigatran) or warfarin to attain therapeutic activated clotting time (ACT) in the RE-CIRCUIT® study. The RE-CIRCUIT study showed significantly fewer major bleeding events in the dabigatran vs. warfarin treatment group. Unfractionated heparin was administered during the procedure to maintain ACT >300 s. METHODS AND RESULTS: Patients were randomly assigned to dabigatran 150 mg bid or international normalized ratio-adjusted warfarin. Ablation was performed with uninterrupted anticoagulation and continued for 8 weeks after the procedure. Heparin was administered after placement of femoral sheaths before or immediately after transseptal puncture. Ablation was performed in 635 patients (dabigatran, 317; warfarin, 318); data were available from 396 patients administered heparin (dabigatran, 191; warfarin, 205). Most frequent time window from last dose of study drug to septal puncture was 0 to <4 h in the dabigatran (41.3%) and 16 to <24 h in the warfarin arms (44.7%). Overall mean (standard deviation) heparin dose was similar between the dabigatran and warfarin groups [12 402 (10 721) vs. 11 910 (8359) IU, respectively]. Heparin dosing requirement to reach therapeutic ACT was lowest when time from last dose of dabigatran to septal puncture was 0 to <4 h. CONCLUSION: Patients treated with dabigatran required a similar amount of unfractionated heparin as those treated with warfarin to achieve an ACT of >300 s during ablation. More heparin units were required when the time from the last dose of dabigatran to septal puncture increased.

Dabigatran dual therapy with ticagrelor or clopidogrel after percutaneous coronary intervention in atrial fibrillation patients with or without acute coronary syndrome: a subgroup analysis from the RE-DUAL PCI trial.

AIMS: After percutaneous coronary intervention (PCI) in patients with atrial fibrillation, safety and efficacy with dabigatran dual therapy were evaluated in pre-specified subgroups of patients undergoing PCI due to acute coronary syndrome (ACS) or elective PCI, and those receiving ticagrelor or clopidogrel treatment. METHODS AND RESULTS: In the RE-DUAL PCI trial, 2725 patients were randomized to dabigatran 110 mg or 150 mg with P2Y12 inhibitor, or warfarin with P2Y12 inhibitor and aspirin. Mean follow-up was 14 months, 50.5% had ACS, and 12% received ticagrelor. The risk of the primary endpoint, major or clinically relevant non-major bleeding event, was reduced with both dabigatran dual therapies vs. warfarin triple therapy in patients with ACS [hazard ratio (95% confidence interval), 0.47 (0.35-0.63) for 110 mg and 0.67 (0.50-0.90) for 150 mg]; elective PCI [0.57 (0.43-0.76) for 110 mg and 0.76 (0.56-1.03) for 150 mg]; receiving ticagrelor [0.46 (0.28-0.76) for 110 mg and 0.59 (0.34-1.04) for 150 mg]; or clopidogrel [0.51 (0.41-0.64) for 110 mg and 0.73 (0.58-0.91) for 150 mg], all interaction P-values >0.10. Overall, dabigatran dual therapy was comparable to warfarin triple therapy for the composite endpoint of death, myocardial infarction, stroke, systemic embolism, or unplanned revascularization, with minor variations across the subgroups, all interaction P-values >0.10. CONCLUSION: The benefits of both dabigatran 110 mg and 150 mg dual therapy compared with warfarin triple therapy in reducing bleeding risks were consistent across subgroups of patients with or without ACS, and patients treated with ticagrelor or clopidogrel.

Regional differences in patient characteristics and outcomes during uninterrupted anticoagulation with dabigatran versus warfarin in catheter ablation of atrial fibrillation: the RE-CIRCUIT study.

PURPOSE: To describe regional differences in patient characteristics, ablation procedures, and bleeding events in the RE-CIRCUIT study. RE-CIRCUIT was a prospective, multicenter study that captured data from different regions, providing an opportunity to understand the practices followed in various regions. The incidence of major bleeding events (MBEs) was significantly lower with uninterrupted dabigatran versus uninterrupted warfarin. METHODS: Patients were randomized to receive dabigatran 150 mg twice daily or warfarin. Ablation was performed with uninterrupted anticoagulation for 8 weeks after the procedure. Regions were Western Europe, Eastern Europe, North America, and Asia. RESULTS: Of 704 patients screened across 104 sites, 635 underwent catheter ablation (dabigatran, 317; warfarin, 318). Patient characteristics were different across various regions. Patients from North America had the highest prevalence of atrial flutter (33%), coronary artery disease (29%), diabetes mellitus (18%), and previous myocardial infarction (9%). Hypertension was most prevalent in Eastern Europe (75%), as was congestive heart failure (40% vs 2% in Western Europe). Pulmonary vein isolation alone was the preferred technique used in most patients (86% in North America and 75-83% elsewhere) and radio frequency was the preferred energy source. The major outcome measure, incidence of MBEs during and up to 2 months after the procedure, was consistently lower with uninterrupted dabigatran versus warfarin, irrespective of regions and their procedural differences, and different ablation techniques utilized. CONCLUSIONS: This analysis shows that the benefits of dabigatran over a vitamin K antagonist in patients undergoing atrial fibrillation ablation are consistent across all geographic regions studied. TRIAL REGISTRATION: NCT02348723 (https://clinicaltrials.gov/ct2/show/NCT02348723).

Efficacy and Safety of the Use of Non-Vitamin K Antagonist Oral Anticoagulants in Patients With Nonvalvular Atrial Fibrillation and Concomitant Aspirin Therapy: A Meta-Analysis of Randomized Trials.

BACKGROUND: Current guidelines recommend non-vitamin K antagonist oral anticoagulants (NOACs) as the first-choice therapy in patients with nonvalvular atrial fibrillation because these drugs have several benefits over the vitamin K antagonists (VKAs). It is unknown whether these benefits remain when NOACs have to be combined with aspirin therapy. To assess the efficacy and safety of NOACs compared with VKAs in patients with atrial fibrillation and concomitant aspirin therapy, we conducted a systematic review and study-based meta-analysis of published randomized controlled trials. METHODS: A systematic electronic literature search was done in MEDLINE, EMBASE, and Cochrane CENTRAL Register of Controlled Trials for studies including published data of patients ≥18 years of age with nonvalvular atrial fibrillation, randomized to either VKAs or NOACs, or receiving aspirin therapy at any time during the study that report all-cause stroke or systemic embolism, vascular death, myocardial infarction, major bleeding, or intracranial hemorrhage as an outcome. Hazard ratios (HRs) with 95% confidence intervals (CIs) for each outcome were extracted from the individual studies and pooled with random-effects meta-analysis. RESULTS: This study-based meta-analysis was restricted to the subgroups of patients on aspirin therapy (n=21 722) from 4 randomized controlled trials comparing VKAs and NOACs (n=71 681) in nonvalvular atrial fibrillation. In this meta-analysis including patients on mainly low-dose aspirin, NOACs were found to be more effective (outcome of stroke or systemic embolism: HR, 0.78; 95% CI, 0.67-0.91; vascular death: HR, 0.85; 95% CI, 0.76-0.93) and as safe as VKAs with respect to major bleeding (HR, 0.83; 95% CI, 0.69-1.01). NOACs were safer with respect to the reduction of intracranial hemorrhage (HR, 0.38; 95% CI, 0.26-0.56). CONCLUSIONS: This study-based meta-analysis shows that it may be both safer and more effective to use NOACs compared with VKAs to treat patients with nonvalvular atrial fibrillation and concomitant aspirin therapy.

Dabigatran vs. warfarin in relation to the presence of left ventricular hypertrophy in patients with atrial fibrillation- the Randomized Evaluation of Long-term anticoagulation therapY (RE-LY) study.

Aim: We tested the hypothesis that left ventricular hypertrophy (LVH) interferes with the antithrombotic effects of dabigatran and warfarin in patients with atrial fibrillation (AF). Methods and results: This is a post-hoc analysis of the Randomized Evaluation of Long-term anticoagulation therapY (RE-LY) Study. We defined LVH by electrocardiography (ECG) and included patients with AF on the ECG tracing at entry. Hazard ratios (HR) for each dabigatran dose vs. warfarin were calculated in relation to LVH. LVH was present in 2353 (22.7%) out of 10 372 patients. In patients without LVH, the rates of primary outcome were 1.59%/year with warfarin, 1.60% with dabigatran 110 mg (HR vs. warfarin 1.01, 95% confidence interval (CI) 0.75-1.36) and 1.08% with dabigatran 150 mg (HR vs. warfarin 0.68, 95% CI 0.49-0.95). In patients with LVH, the rates of primary outcome were 3.21%/year with warfarin, 1.69% with dabigatran 110 mg (HR vs. warfarin 0.52, 95% CI 0.32-0.84) and 1.55% with 150 mg (HR vs. warfarin 0.48, 95% CI 0.29-0.78). The interaction between LVH status and dabigatran 110 mg vs. warfarin was significant for the primary outcome (P = 0.021) and stroke (P = 0.016). LVH was associated with a higher event rate with warfarin, not with dabigatran. In the warfarin group, the time in therapeutic range was significantly lower in the presence than in the absence of LVH. Conclusions: LVH was associated with a lower antithrombotic efficacy of warfarin, but not of dabigatran, in patients with AF. Consequently, the relative benefit of the lower dose of dabigatran compared to warfarin was enhanced in patients with LVH. The higher dose of dabigatran was superior to warfarin regardless of LVH status. Clinical trial registration: http:www.clinicaltrials.gov. Unique identifier: NCT00262600.

Dual Antithrombotic Therapy with Dabigatran after PCI in Atrial Fibrillation.

BACKGROUND: Triple antithrombotic therapy with warfarin plus two antiplatelet agents is the standard of care after percutaneous coronary intervention (PCI) for patients with atrial fibrillation, but this therapy is associated with a high risk of bleeding. METHODS: In this multicenter trial, we randomly assigned 2725 patients with atrial fibrillation who had undergone PCI to triple therapy with warfarin plus a P2Y12 inhibitor (clopidogrel or ticagrelor) and aspirin (for 1 to 3 months) (triple-therapy group) or dual therapy with dabigatran (110 mg or 150 mg twice daily) plus a P2Y12 inhibitor (clopidogrel or ticagrelor) and no aspirin (110-mg and 150-mg dual-therapy groups). Outside the United States, elderly patients (≥80 years of age; ≥70 years of age in Japan) were randomly assigned to the 110-mg dual-therapy group or the triple-therapy group. The primary end point was a major or clinically relevant nonmajor bleeding event during follow-up (mean follow-up, 14 months). The trial also tested for the noninferiority of dual therapy with dabigatran (both doses combined) to triple therapy with warfarin with respect to the incidence of a composite efficacy end point of thromboembolic events (myocardial infarction, stroke, or systemic embolism), death, or unplanned revascularization. RESULTS: The incidence of the primary end point was 15.4% in the 110-mg dual-therapy group as compared with 26.9% in the triple-therapy group (hazard ratio, 0.52; 95% confidence interval [CI], 0.42 to 0.63; P<0.001 for noninferiority; P<0.001 for superiority) and 20.2% in the 150-mg dual-therapy group as compared with 25.7% in the corresponding triple-therapy group, which did not include elderly patients outside the United States (hazard ratio, 0.72; 95% CI, 0.58 to 0.88; P<0.001 for noninferiority). The incidence of the composite efficacy end point was 13.7% in the two dual-therapy groups combined as compared with 13.4% in the triple-therapy group (hazard ratio, 1.04; 95% CI, 0.84 to 1.29; P=0.005 for noninferiority). The rate of serious adverse events did not differ significantly among the groups. CONCLUSIONS: Among patients with atrial fibrillation who had undergone PCI, the risk of bleeding was lower among those who received dual therapy with dabigatran and a P2Y12 inhibitor than among those who received triple therapy with warfarin, a P2Y12 inhibitor, and aspirin. Dual therapy was noninferior to triple therapy with respect to the risk of thromboembolic events. (Funded by Boehringer Ingelheim; RE-DUAL PCI ClinicalTrials.gov number, NCT02164864 .).

Healthcare resource utilization in patients receiving idarucizumab for reversal of dabigatran anticoagulation due to major bleeding, urgent surgery, or procedural interventions: interim results from the RE-VERSE AD™ study.

AIMS: Patients treated with anticoagulants may experience serious bleeding or require urgent surgery or intervention, and may benefit from rapid anticoagulant reversal. This exploratory analysis assessed healthcare resource utilization (HCRU) in patients treated with idarucizumab, a specific reversal agent for dabigatran etexilate. MATERIALS AND METHODS: RE-VERSE AD™ (NCT02104947), a prospective, multi-center open-label study, is evaluating idarucizumab for dabigatran reversal in patients with serious bleeding (Group A) or undergoing emergency surgery/procedures (Group B). HCRU outcome measures evaluated in the first 90 patients enrolled were use of blood products and pro-hemostatic agents, length of stay (LOS) in hospital, and LOS in intensive care unit (ICU). RESULTS: Blood products or pro-hemostatic agents were given to 63% (32/51) of patients in Group A and 23% (9/39) of patients in Group B on the day of/day after surgery. An overnight hospital stay was reported for 82% (42/51) of patients in Group A with median LOS = 7 (range = 1-71) bed-days. For Group B, 92% (36/39) had an overnight hospital stay with a median LOS = 9 (range = 1-92) bed-days. In Group A, 17 patients were admitted to the ICU for at least 1 day with median LOS = 4 (range = 1-44) days; in Group B the number was 15 with median LOS = 2 (range = 1-92) days. LIMITATIONS: The lack of a control group and the small patient numbers limit the strength of the conclusions. CONCLUSIONS: The use of idarucizumab may simplify emergency management of dabigatran-treated patients with life-threatening bleeds and reduce perioperative complications in patients undergoing emergency surgery.

Antithrombotic therapy use in patients with atrial fibrillation before the era of non-vitamin K antagonist oral anticoagulants: the Global Registry on Long-Term Oral Antithrombotic Treatment in Patients with Atrial Fibrillation (GLORIA-AF) Phase I cohort.

AIMS: The introduction of non-VKA oral anticoagulants (NOACs), which differ from the earlier vitamin K antagonist (VKA) treatments, has changed the approach to stroke prevention in atrial fibrillation (AF). GLORIA-AF is a prospective, global registry programme describing the selection of antithrombotic treatment in newly diagnosed AF patients at risk of stroke. It comprises three phases: Phase I, before the introduction of NOACs; Phase II, during the time of the introduction of dabigatran, the first NOAC; and Phase III, once NOACs have been established in clinical practice. METHODS AND RESULTS: In Phase I, 1063 patients were eligible from the 1100 enrolled (54.3% male; median age 70 years); patients were from China (67.1%), Europe (EU; 27.4%), and the Middle East (ME; 5.6%). The majority of patients using VKAs had high stroke risk (CHA2DS2-VASc ≥ 2; 86.5%); 13.5% had moderate risk (CHA2DS2-VASc = 1). Vitamin K antagonist use was higher for persistent/permanent AF (47.7%) than that for paroxysmal (23.9%). Most patients in China were treated with antiplatelet agents (53.7%) vs. 27.1% in EU and 28.8% in ME. In China, 25.9% of patients had no antithrombotic therapy, vs. 8.6% in EU and 8.5% in ME. CONCLUSION: Phase I of GLORIA-AF shows that VKAs were mostly used in patients with persistent/permanent (vs. paroxysmal) AF and in those with high stroke risk. Furthermore, there were meaningful geographical differences in the use of VKA therapy in the era before the availability of NOACs, including a much lower use of VKAs in China, where most patients either received antiplatelet agents or no antithrombotic treatment.

Observational study of dabigatran etexilate 150mg in patients with moderate renal impairment undergoing elective total hip or knee replacement.

INTRODUCTION: The standard dabigatran etexilate dosage for prevention of venous thromboembolism (VTE) after elective total hip or knee replacement (THR/TKR) is 220mg once daily (qd), with 150mg qd for patients with moderate renal impairment. As clinical trial experience in patients with moderate renal impairment was limited at the time of approval, we conducted an observational study to evaluate the 150mg qd dose. MATERIALS AND METHODS: This open-label, prospective, uncontrolled, observational study in patients with creatinine clearance (CrCl) 30-50mL/min was conducted in seven European countries. Patients received 75mg dabigatran etexilate 1-4h after surgery and 150mg qd on days 2-10 (TKR) or 2-35 (THR), per the European Summary of Product Characteristics. Coprimary outcomes were major bleeding events (MBEs) and a composite of symptomatic VTE and all-cause mortality. RESULTS: 428 renally impaired patients with median CrCl 43.4mL/min (range 30.0-49.9), and median age 80years (range 32-96) received dabigatran etexilate: median treatment duration THR 31days, TKR 28days. Ten MBEs occurred in nine patients (2.1%; 95% confidence interval [CI]: 1.0-4.0; THR 1.8%; TKR 2.4%); none were fatal or involved a critical organ. Symptomatic VTE and all-cause mortality occurred in three patients (0.7%; 95% CI: 0.1-2.0; THR 0.9%; TKR 0.5%). Overall, 54 patients discontinued treatment prematurely, including 35 due to an adverse event (nine bleeding-related) and 16 switching to another anticoagulant. CONCLUSIONS: Dabigatran etexilate 150mg qd had a good safety profile and was efficacious in fragile, elderly, renally impaired patients undergoing THR or TKR. These findings from the clinical practice setting add to the existing clinical trial data.

Dabigatran etexilate for thromboprophylaxis in over 5000 hip or knee replacement patients in a real-world clinical setting.

BACKGROUND: Thromboprophylaxis is recommended for patients undergoing total hip or total knee replacement (THR, TKR). An international, open-label, prospective, observational, single-arm study in a routine clinical setting was performed to assess the safety and efficacy of dabigatran etexilate 220 mg once daily in patients undergoing THR or TKR, and in subgroups of patients with potentially increased risk of bleeding or venous thromboembolism (VTE). MATERIALS AND METHODS: Patients were ≥18 years and required to be eligible to receive dabigatran 220 mg once daily (first dose 110 mg 1-4 h after THR/TKR surgery) according to the European Summary of Product Characteristics. The primary safety and efficacy outcomes were incidence of major bleeding events (MBEs), and the composite incidence of symptomatic VTE events and all-cause mortality, respectively. RESULTS: In total, 5292 patients (median age 64 years) were enrolled and received dabigatran (2734 THR and 2558 TKR). Median drug exposure was 31 days (THR 34 days; TKR 27 days). Overall incidence of MBEs was 0.72 % (95 % confidence interval [CI] 0.51, 0.98), and this rate was comparable between types of surgery and was not significantly affected by protocol-defined risk factors. The overall incidence of symptomatic VTE and all-cause mortality was 1.04 % (95 % CI 0.78, 1.35); the only significant risk factor was history of VTE events (odds ratio 5.59; 95 % CI 2.53, 11.08). A post-hoc analysis showed that the incidence of MBEs in this observational study was similar to or lower than those reported in previous phase 3 trials. CONCLUSIONS: Results from this observational study of dabigatran etexilate administered to patients undergoing THR or TKR surgery are reassuring and supportive of those obtained in dabigatran phase 3 trials. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT00846807.

Safety and efficacy of switching from low molecular weight heparin to dabigatran in patients undergoing elective total hip or knee replacement surgery.

BACKGROUND: The aim of this study was to assess the safety and efficacy of switching therapy from low molecular weight heparin (LMWH; enoxaparin) to dabigatran for prevention of venous thromboembolic events (VTE) in patients undergoing elective total hip or knee replacement surgery (THR/TKR). METHODS: This was a prospective, multicenter, open-label, single-arm, observational, study in patients undergoing THR or TKR who were to receive enoxaparin 40 mg for thromboprophylaxis. Enoxaparin was initiated before or after surgery according to local practice, and was switched to dabigatran 220 mg once daily at a time point chosen by the investigator. The coprimary endpoints were major bleeding events, and the composite of symptomatic VTE and all-cause mortality, from last use of enoxaparin to 24 h after last intake of dabigatran. RESULTS: Altogether, 168 (81 THR, 87 TKR) patients were enrolled, of whom 161 received both enoxaparin and dabigatran, 2 received dabigatran only and 5 received enoxaparin only. The median time of the first dabigatran tablet was 24.0 h after the last LMWH dosage and the median number of days on dabigatran treatment was 36 days. No symptomatic VTE or death occurred during the study. One major bleeding event was seen at the surgical site and required treatment cessation. Three minor bleeding events were observed. CONCLUSIONS: In the normal clinical setting, switching from LMWH to dabigatran in patients who had undergone THR and TKR was safe and effective in preventing VTE. The reported adverse events and serious adverse events were consistent with the known safety profile for dabigatran. Switching from a subcutaneous to an oral anticoagulant may offer greater convenience in the outpatient setting after discharge. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT01153698.

Efficacy and Safety of Dabigatran Etexilate vs. Warfarin in Asian RE-LY Patients According to Baseline Renal Function or CHADS2 Score.

BACKGROUND: In Asian patients in RE-LY, dabigatran etexilate (DE) was as effective as warfarin, with a significantly lower bleeding risk. We evaluated the relationship between baseline renal function or CHADS2 score and efficacy or safety outcomes in these patients. METHODS AND RESULTS: Asian patients (n=2,782) were categorized according to baseline renal function or CHADS2 score, and efficacy and safety outcomes were analyzed for DE (110 mg and 150 mg b.i.d.) vs. warfarin. There was an increase in the rates of stroke/systemic embolism and major bleeding with worsening renal function and CHADS2 score. For stroke/systemic embolism (primary efficacy endpoint), there was no treatment interaction for dabigatran at either 110 or 150 mg b.i.d. compared with warfarin related to patients' baseline renal function (Pinteraction=0.56 for DE 110 mg and 0.62 for DE 150 mg vs. warfarin) or CHADS2 score (Pinteraction=0.68 for DE 110 mg and 0.31 for DE 150 mg vs. warfarin). For major bleeding, there was no treatment interaction by creatinine clearance category observed for either dose (Pinteraction=0.60 and 0.62 for DE 110 mg and DE 150 mg, respectively). Baseline CHADS2 score had no significant effect on bleeding event rates with DE vs. warfarin. CONCLUSIONS: Bleeding and stroke rates in Asian patients varied according to renal function and CHADS2 score, but the relative benefits of DE over warfarin were preserved when analyzed by subcategories.