[1] Univ Ulsan, Asan Med Ctr, Dept Thorac & Cardiovasc Surg, Coll Med, Seoul, South Korea
[2] Hallym Univ, Hallym Sacred Heart Hosp, Dept Internal Med, Div Cardiol,Coll Med, Anyang, South Korea
[3] Univ Ulsan, Asan Med Ctr, Dept Internal Med, Div Cardiol,Coll Med, Seoul, South Korea
[4] Univ Ulsan, Asan Med Ctr, Dept Clin Epidemiol & Biostat, Coll Med, Seoul, South Korea
[5] Univ Ulsan, Asan Med Ctr, Dept Internal Med, Div Cardiol,Coll Med, 88 Olymp Ro 43 Gil, Seoul 05505, South Korea