title: Association between time to percutaneous coronary intervention and hospital mortality in non-STEMI: a prospective multicenter observational study.
abstract: OBJECTIVE
  This study aimed to investigate the association between time to percutaneous coronary intervention (PCI) and hospital mortality in non-ST-elevation myocardial infarction (NSTEMI).
  
  
  METHODS
  Adult patients with NSTEMI were enrolled from November 2007 to December 2012 at 28 emergency departments (EDs) in Korea, excluding those who met the following criteria: age less than 20 years, PCI not performed or performed after 72 hours, cardiac arrest at ED presentation, and unknown outcome. Exposure variable was defined as early PCI (<6 hours after ED arrival) and late PCI group (≥6 hours). The primary outcome was hospital mortality. The adjusted odds ratios (ORs) with 95% confidence intervals (95% CIs) for late vs early PCI on mortality were calculated in original data set and propensity score-matched data set using multivariable logistic regression models with/without interaction term (PCI group and time from symptom to ED arrival within 12 hours, or S2D).
  
  
  RESULTS
  A total of 4363 patients were analyzed as early (n = 1109) and late (n = 3254) PCI groups. The mortality rates were 2.4%, 5.4%, and 1.5% for the total, early, and late PCI groups, respectively. Adjusted ORs (95% CIs) of late PCI for hospital mortality were 0.36 (0.22-0.61) in the original cohort and 0.29 (0.27-0.48) in the propensity score-matched cohort, respectively. Adjusted ORs (95% CIs) in the propensity score-matched subset were 0.28 (0.17-0.45) in the short S2D group and 0.50 (0.18-1.37) in the long S2D group, respectively.
  
  
  CONCLUSIONS
  Percutaneous coronary intervention earlier than 6 hours after ED presentation was associated with higher hospital mortality than PCI 6 hours later in NSTEMI. However, the effect disappeared in the long S2D group.
authors.affiliation: Department of Emergency Medicine, Seoul National University College of Medicine, Seoul, Korea. Electronic address: tgkim.md@gmail.com.
authors.forename: Tae Gyun
authors.initials: TG
authors.lastname: Kim
authors.affiliation: Department of Emergency Medicine, Seoul National University College of Medicine, Seoul, Korea. Electronic address: shinsangdo@medimail.co.kr.
authors.forename: Sang Do
authors.initials: SD
authors.lastname: Shin
authors.affiliation: Department of Emergency Medicine, Seoul National University College of Medicine, Seoul, Korea. Electronic address: skciva@gmail.com.
authors.forename: Kyoung Jun
authors.initials: KJ
authors.lastname: Song
authors.affiliation: Department of Emergency Medicine, Seoul National University College of Medicine, Seoul, Korea. Electronic address: eyeblack99@gmail.com.
authors.forename: Yu Jin
authors.initials: YJ
authors.lastname: Lee
authors.affiliation: Department of Emergency Medicine, Seoul National University College of Medicine, Seoul, Korea. Electronic address: ironlyj@gmail.com.
authors.forename: Eui Jung
authors.initials: EJ
authors.lastname: Lee
authors.affiliation: Laboratory of Emergency Medical Services, Seoul National University Hospital Biomedical Research Institute, Seoul, Korea. Electronic address: Ro.youngsun@gmail.com.
authors.forename: Young Sun
authors.initials: YS
authors.lastname: Ro
authors.affiliation: Laboratory of Emergency Medical Services, Seoul National University Hospital Biomedical Research Institute, Seoul, Korea. Electronic address: arendt75@gmail.com.
authors.forename: Ki Ok
authors.initials: KO
authors.lastname: Ahn
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000401:mortality / Q000628:therapy*; D016017:Odds Ratio; D062645:Percutaneous Coronary Intervention; D057216:Propensity Score; D011446:Prospective Studies; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome