[1] Univ Ulsan, Coll Med, Asan Med Ctr, Dept Cardiol, Seoul, South Korea
[2] Univ Ulsan, Coll Med, Asan Med Ctr, Dept Geriatr, Seoul, South Korea
[3] Univ Ulsan, Coll Med, Asan Med Ctr, Dept Clin Epidemiol & Biostat, Seoul, South Korea
[4] Univ Ulsan, Coll Med, Asan Med Ctr, Dept Radiol, Seoul, South Korea
[5] Univ Ulsan, Coll Med, Asan Med Ctr, Dept Thorac & Cardiac Surg, Seoul, South Korea