Dabigatran vs. Aspirin for Secondary Prevention After Embolic Stroke of Undetermined Source　― Japanese Subanalysis of the RE-SPECT ESUS Randomized Controlled Trial

Background:The international 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 (RE-SPECT ESUS) trial did not demonstrate superiority of dabigatran over aspirin for reduction of recurrent strokes in patients with embolic strokes of undetermined source (ESUS). Based on pre-defined subanalyses, the safety and efficacy of dabigatran vs. aspirin in Japanese patients was assessed.Methods and Results:ESUS patients were randomized to receive either dabigatran (150 or 110 mg twice daily) or aspirin (100 mg once daily). Of 5,390 patients randomized, 594 were Japanese. Most Japanese patients (99.8%) underwent brain magnetic resonance imaging for trial screening, compared to 76.8% of non-Japanese (P