Myocardial Ischemic Events in Patients with Atrial Fibrillation Treated with Dabigatran or Warfarin in the RE-LY Trial
Background—There is a modest risk of myocardial infarction (MI) and myocardial ischemic events in patients with atrial fibrillation.
Methods and Results—Using data from the RE-LY study, rates of MI, unstable angina, cardiac arrest and cardiac death, pre-specified net clinical benefit and treatment effects of dabigatran versus warfarin are reported. MI occurred at annual rates of 0.82% and 0.81% on dabigatran 110 mg or 150 mg BID, compared to 0.64% on warfarin (hazard ratio (HR) 1.29, 95% confidence interval (CI) 0.96-1.75; p=0.09 for dabigatran 110 mg; and HR 1.27, 95% CI 0.94-1.71; p=0.12 for dabigatran 150 mg). Annual rates of a composite of MI, unstable angina, cardiac arrest, and cardiac death were 3.16%/yr on dabigatran 110 mg, 3.33%/yr on dabigatran 150 mg, and 3.41%/yr on warfarin (HR versus warfarin 0.93 (95% CI 0.80-1.06; p=0.28) for dabigatran 110 mg and 0.98 (95% CI 0.85-1.12; p=0.77) for dabigatran 150 mg. Events pre-specified as "net clinical benefit" (all strokes, systemic embolism, MI, PE, major bleeding, all-cause death) occurred 7.34%/yr on dabigatran 110 mg, 7.11%/yr on dabigatran 150 mg, and 7.91%/yr on warfarin (HR 0.92 (95% CI 0.81-1.01; p=0.09) for dabigatran 110 mg and 0.90 (95% CI 0.82-0.99; p=0.02 for dabigatran 150 mg). The relative effects of dabigatran versus warfarin on myocardial ischemic events were consistent in patients with or without a baseline history of MI/CAD.
Conclusions—There was a non-significant increase in MI with dabigatran compared to warfarin, but other myocardial ischemic events were not increased. Treatment effects of dabigatran are consistent in patients at higher and lower risk of myocardial ischemic events.
Clinical Trial Registration Information—ClinicalTrials.gov; NCT 00262600
- Received July 13, 2011.
- Accepted November 17, 2011.
- Copyright © 2012, American Heart Association, Inc. All rights reserved. Unauthorized use prohibited