Kim HL, Kang SH, Yoon CH, Cho YS, Youn TJ, Cho GY, Chae IH, Kim HS, Chae SC, Cho MC, Kim YJ, Kim JH, Ahn Y, Jeong MH, Choi DJ, Other Korea Acute Myocardial Infarction Registry (KAMIR) and Korea Working Group on Myocardial Infarction (KorMI) Investigators