title: Health care system delay and heart failure in patients with ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention: follow-up of population-based medical registry data.
abstract: BACKGROUND
  In patients with ST-segment elevation myocardial infarction (STEMI), delay between contact with the health care system and initiation of reperfusion therapy (system delay) is associated with mortality, but data on the associated risk for congestive heart failure (CHF) among survivors are limited.
  
  
  OBJECTIVE
  To evaluate the association between system delay and the risk for readmissions or outpatient contacts due to CHF after primary percutaneous coronary intervention (PPCI) in patients with STEMI.
  
  
  METHODS
  Historical follow-up study using population-based medical registries.
  
  
  METHODS
  Western Denmark.
  
  
  METHODS
  Patients with STEMI who were transported by emergency medical service from 1 January 1999 to 7 February 2010 and treated with PPCI within 12 hours of symptom onset and who had a system delay of 6 hours or less (n = 7952). The median duration of follow-up was 3.1 years.
  
  
  METHODS
  Cumulative incidence of readmissions or outpatient contacts due to CHF was determined by using competing-risk regression analysis, with death as the competing risk. Crude and adjusted cause-specific hazard ratios for readmissions or outpatient contacts due to CHF were determined for system delay and other covariates.
  
  
  RESULTS
  System delays of 60 minutes or less (n = 451), 61 to 120 minutes (n = 3457), 121 to 180 minutes (n = 2655), and 181 to 360 minutes (n = 1389) corresponded with long-term risks for readmissions or outpatient contacts due to CHF of 10.1%, 10.6%, 12.3%, and 14.1%, respectively (P < 0.001). In multivariable analysis, system delay was an independent predictor of readmissions or outpatient contacts due to CHF (adjusted hazard ratio per hour increase in delay, 1.10 [95% CI, 1.02 to 1.17]).
  
  
  CONCLUSIONS
  In any nonrandomized study, there are risks for selection bias and residual confounding.
  
  
  CONCLUSIONS
  In patients with STEMI, shorter delay to PPCI is associated with lower risk for readmissions or outpatient contacts due to CHF during follow-up.
authors.affiliation: Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Christian Juhl
authors.initials: CJ
authors.lastname: Terkelsen
authors.forename: Lisette Okkels
authors.initials: LO
authors.lastname: Jensen
authors.forename: Hans-Henrik
authors.initials: HH
authors.lastname: Tilsted
authors.forename: Sven
authors.initials: S
authors.lastname: Trautner
authors.forename: Søren Paaske
authors.initials: SP
authors.lastname: Johnsen
authors.forename: Werner
authors.initials: W
authors.lastname: Vach
authors.forename: Hans Erik
authors.initials: HE
authors.lastname: Bøtker
authors.forename: Leif
authors.initials: L
authors.lastname: Thuesen
authors.forename: Jens Flensted
authors.initials: JF
authors.lastname: Lassen
mesh_terms: D000553:Ambulatory Care / Q000706:statistics & numerical data*; D015906:Angioplasty, Balloon, Coronary; D015982:Bias; D015986:Confounding Factors, Epidemiologic; D004562:Electrocardiography; D004632:Emergency Medical Services / Q000592:standards; D005500:Follow-Up Studies; D006333:Heart Failure / Q000209:etiology / Q000628:therapy*; D006801:Humans; D009203:Myocardial Infarction / Q000150:complications* / Q000175:diagnosis / Q000628:therapy*; D010359:Patient Readmission / Q000706:statistics & numerical data*; D012042:Registries; D012307:Risk Factors; D013997:Time Factors