Division of Cardiology, Saiseikai Kumamoto Hospital Cardiovascular Center, Kumamoto, Japan. Electronic address: okumura@hirosaki-u.ac.jp. Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, United Kingdom; Aalborg Thrombosis Research Unit, Department of Clinical Medicine, Aalborg University, Aalborg, Denmark. Department of Cardiology, National Hospital Organization Kyoto Medical Center, Kyoto, Japan. Clinical Development Department, Daiichi Sankyo Co Ltd, Tokyo, Japan. Clinical Data and Biostatistics Department, Daiichi Sankyo Co Ltd, Tokyo, Japan. Department of Geriatric Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan. Cardiovascular Institute, Tokyo, Japan.