title: Impact of door-to-balloon time on long-term mortality in high- and low-risk patients with ST-elevation myocardial infarction.
abstract: BACKGROUND
  Door-to-balloon time (DTBT) less than 90min remains the benchmark of timely reperfusion in ST-elevation myocardial infarction (STEMI). The relative long-term benefit of timely reperfusion in STEMI patients with differing risk profiles is less certain. Thus, we aimed to assess the impact of DTBT on long-term mortality in high- and low-risk STEMI patients.
  
  
  METHODS
  We analysed baseline clinical and procedural characteristics of 2539 consecutive STEMI patients who underwent primary percutaneous coronary intervention (PCI) from the Melbourne Interventional Group registry from 2004 to 2012. Patients were classified high risk (HR-STEMI) if they presented with cardiogenic shock, out-of-hospital cardiac arrest (OHCA) or Killip class ≥2; or low-risk (LR-STEMI) if there were no high-risk features. We then stratified high- and low-risk patients by DTBT (≤90min vs. >90min) and assessed long-term mortality.
  
  
  RESULTS
  Of the 2539 patients, 395 (16%) met the high-risk criteria. A DTBT ≤90min was achieved in 43% of HR-STEMI patients and in 55% of LR-STEMI patients. Patients in the HR-STEMI compared to LR-STEMI cohort had higher in-hospital (31% vs. 1%, p<0.01) and long-term mortality (37% vs. 7%, p<0.01). A DTBT ≤90min was associated with significant improvements in short- and long-term mortality in both groups. A DTBT ≤90min was an independent multivariate predictor of long-term survival in LR-STEMI (hazard ratio [HR] 0.5, 95% confidence interval [CI] 0.3-0.9, p=0.02) but not in HR-STEMI (HR 0.7, 95% CI 0.5-1.1, p=0.11).
  
  
  CONCLUSIONS
  A DTBT ≤90min was associated with improved short- and long-term outcomes in high- and low-risk STEMI patients. However, it was only an independent predictor of long-term survival in LR-STEMI patients.
authors.affiliation: Department of Cardiology, Austin Health, Melbourne, Australia; University of Melbourne, Melbourne, Australia.
authors.forename: Matias B
authors.initials: MB
authors.lastname: Yudi
authors.affiliation: Department of Cardiology, Austin Health, Melbourne, Australia; University of Melbourne, Melbourne, Australia.
authors.forename: Jay
authors.initials: J
authors.lastname: Ramchand
authors.affiliation: Department of Cardiology, Austin Health, Melbourne, Australia; University of Melbourne, Melbourne, Australia.
authors.forename: Omar
authors.initials: O
authors.lastname: Farouque
authors.affiliation: Centre of Cardiovascular Research and Education in Therapeutics (CCRE), Monash University, Melbourne, Australia.
authors.forename: Nick
authors.initials: N
authors.lastname: Andrianopoulos
authors.affiliation: Department of Cardiology, Alfred Hospital, Melbourne, Australia.
authors.forename: William
authors.initials: W
authors.lastname: Chan
authors.affiliation: Centre of Cardiovascular Research and Education in Therapeutics (CCRE), Monash University, Melbourne, Australia; Department of Cardiology, Alfred Hospital, Melbourne, Australia.
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Duffy
authors.affiliation: Department of Cardiology, Royal Melbourne Hospital, Melbourne, Australia.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Lefkovits
authors.affiliation: Centre of Cardiovascular Research and Education in Therapeutics (CCRE), Monash University, Melbourne, Australia.
authors.forename: Angela
authors.initials: A
authors.lastname: Brennan
authors.affiliation: Department of Cardiology, Austin Health, Melbourne, Australia.
authors.forename: Ryan
authors.initials: R
authors.lastname: Spencer
authors.affiliation: Department of Cardiology, Austin Health, Melbourne, Australia.
authors.forename: Dharsh
authors.initials: D
authors.lastname: Fernando
authors.affiliation: Department of Cardiology, Geelong Hospital, Geelong, Australia.
authors.forename: Chin
authors.initials: C
authors.lastname: Hiew
authors.affiliation: Department of Cardiology, Box Hill Hospital, Melbourne, Australia.
authors.forename: Melanie
authors.initials: M
authors.lastname: Freeman
authors.affiliation: Centre of Cardiovascular Research and Education in Therapeutics (CCRE), Monash University, Melbourne, Australia; School of Public Health, Curtin University, Perth, Western Australia, Australia.
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Reid
authors.affiliation: University of Melbourne, Melbourne, Australia; Centre of Cardiovascular Research and Education in Therapeutics (CCRE), Monash University, Melbourne, Australia; Department of Cardiology, Royal Melbourne Hospital, Melbourne, Australia.
authors.forename: Andrew E
authors.initials: AE
authors.lastname: Ajani
authors.affiliation: Department of Cardiology, Austin Health, Melbourne, Australia; University of Melbourne, Melbourne, Australia. Electronic address: david.clark@austin.org.au.
authors.forename: David J
authors.initials: DJ
authors.lastname: Clark
mesh_terms: D000368:Aged; D015906:Angioplasty, Balloon, Coronary / Q000401:mortality / Q000639:trends; D001315:Australia / Q000453:epidemiology; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D017052:Hospital Mortality / Q000639:trends; D006801:Humans; D008297:Male; D008875:Middle Aged; D009026:Mortality / Q000639:trends; D062645:Percutaneous Coronary Intervention / Q000401:mortality* / Q000639:trends; D012042:Registries; D012307:Risk Factors; D000072657:ST Elevation Myocardial Infarction / Q000401:mortality* / Q000601:surgery*; D061665:Time-to-Treatment / Q000639:trends; D016896:Treatment Outcome
keywords: Cardiogenic shock; Door-to-balloon-time; Out-of-hospital cardiac arrest; Percutaneous coronary intervention; Risk assessment; STEMI