OJ-360 Which Lesion Needs Thrombectomy in Acute Myocardial Infarction? : The Evaluation of Myocardial Salvage Effect with Delayed-enhancement MRI(Acute myocardial infarction, clinical (diagnosis/treatment)-4 (IHD) OJ60,Oral Presentation (Japanese),The 70th Anniversary Annual Scientific Meeting of the Japanese Circulation Society)