Abstract： Background Post myocardial infarction (post-MI) patients with low left ventricular ejection fraction (LVEF) have been candidates for an implantable cardioverter-deflbrillator (ICD) since the Multicenter Automatic Defibrillator Implantation Trail II (MADIT II).However,due to the high costs of ICDs,widespread usage has not been accepted.Therefore,further risk stratification for post-MI patients with low LVEF may aid in the selection of patients that will benefit most from ICD treatment.Methods Four hundred and seventeen post-MI patients with low LVEF (≤35%) were enrolled in the study.All the patients received standard examination and proper treatment and were followed up to observe the all-cause death rate and sudden cardiac death (SCD) rate.Then COX proportional-hazards regression model was used to investigate the clinical factors which affect the all-cause death rate and SCD rate.Results Of 55 patients who died during (32±24) months of follow-up,37 (67%) died suddenly.After adjusting for baseline clinical characteristics,multivariate COX proportional-hazards regression model identified the following variables associated with death from all causes:New York Heart Association (NYHA) heart failure class ≥111 (Hazard ratio:2.361),LVEF ≤20% (Hazard ratio:2.514),sustained ventricular tachycardia (Hazard ratio:6.453),and age ≥70 years (Hazard ratio:3.116).The presence of sustained ventricular tachycardia (Hazard ratio:6.491) and age ≥70 years (Hazard ratio:2.694) were specifically associated with SCD.Conclusions In the post-MI patients with low LVEF,factors as LVEF ≤20%,age ≥70 years,presence of ventricular tachycardia,and NYHA heart failure class≥111 predict an adverse outcome.The presence of sustained ventricular tachycardia and age ≥70 years was associated with occurrence of SCD in these patients.