title: Initial complications and factors related to prehospital mortality in acute myocardial infarction with ST segment elevation.
abstract: OBJECTIVE
  Hospital mortality in myocardial infarction ST-elevation myocardial infarction has decreased in recent years, in contrast to prehospital mortality. Our objective was to determine initial complications and factors related to prehospital mortality in patients with acute myocardial infarction with ST segment elevation (STEMI).
  
  
  METHODS
  Observational study based on a prospective continuous register of patients of any age attended by out-of-hospital emergency teams in Andalusia between January 2006 and June 2009. This includes patients with acute coronary syndrome-like symptoms whose initial ECG showed ST elevation or presumably new left bundle branch block (LBBB). Epidemiological, prehospital data and final diagnostic were recorded. The study included all patients with STEMI on the register, without age restrictions. Forward stepwise logistic regression analysis was performed to control for confounders.
  
  
  RESULTS
  A total of 2528 patients were included, 24% were women. Mean age 63.4±13.4 years; 16.7% presented atypical clinical symptoms. Initial complications: ventricular fibrillation (VF) 8.4%, severe bradycardia 5.8%, third-degree atrial-ventricular (AV) block 2.4% and hypotension 13.5%. Fifty-two (2.1%) patients died before reaching hospital. Factors associated with prehospital mortality were female sex (OR 2.36, CI 1.28 to 4.33), atypical clinical picture (OR 2.31, CI 1.21 to 4.41), hypotension (OR 4.95, CI 2.60 to 9.20), LBBB (OR 4.29, CI 1.71 to 10.74), extensive infarction (ST elevation in ≥5 leads) (OR 2.53, CI 1.28 to 5.01) and VF (OR 2.82, CI 1.38 to 5.78).
  
  
  CONCLUSIONS
  A significant proportion of patients with STEMI present early complications in the prehospital setting, and some die before reaching hospital. Prehospital mortality was associated with female sex and atypical presentation, as pre-existing conditions, and hypotension, extensive infarction, LBBB and VF on emergency team attendance.
authors: Empresa Pública de Emergencias Sanitarias de Andalucía. Andalusian Health Ministry, Andalucía, Spain.
authors: Fernando
authors: F
authors: Rosell-Ortiz
authors: Department of Urgencias, Hospital el Toyo, Almería, Spain.
authors: Francisco J
authors: FJ
authors: Mellado-Vergel
authors: Empresa Pública de Emergencias Sanitarias de Andalucía. Andalusian Health Ministry, Andalucía, Spain.
authors: Patricia
authors: P
authors: Fernández-Valle
authors: Empresa Pública de Emergencias Sanitarias de Andalucía. Andalusian Health Ministry, Andalucía, Spain.
authors: Ismael
authors: I
authors: González-Lobato
authors: Empresa Pública de Emergencias Sanitarias de Andalucía. Andalusian Health Ministry, Andalucía, Spain.
authors: Manuela
authors: M
authors: Martínez-Lara
authors: Empresa Pública de Emergencias Sanitarias de Andalucía. Andalusian Health Ministry, Andalucía, Spain.
authors: María M
authors: MM
authors: Ruiz-Montero
authors: Empresa Pública de Emergencias Sanitarias de Andalucía. Andalusian Health Ministry, Andalucía, Spain.
authors: Francisco
authors: F
authors: Romero-Morales
authors: Empresa Pública de Emergencias Sanitarias de Andalucía. Andalusian Health Ministry, Andalucía, Spain.
authors: Itziar
authors: I
authors: Vivar Díaz
authors: Intensive Care Unit, Hospital Clínico, Málaga, Spain.
authors: Ángel
authors: Á
authors: García-Alcántara
authors: Empresa Pública de Emergencias Sanitarias de Andalucía. Andalusian Health Ministry, Andalucía, Spain.
authors: Javier
authors: J
authors: García del Águila
mesh_terms: D000208:Acute Disease; D000368:Aged; D001145:Arrhythmias, Cardiac; D053840:Brugada Syndrome; D000075224:Cardiac Conduction System Disease; D004562:Electrocardiography; D004632:Emergency Medical Services / Q000706:statistics & numerical data*; D005260:Female; D006329:Heart Conduction System / Q000002:abnormalities; D006801:Humans; D007022:Hypotension / Q000150:complications; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000401:mortality*; D011446:Prospective Studies; D012307:Risk Factors; D012737:Sex Factors
keywords: cardiac care, acute myocardal infarct; death/mortality; emergency ambulance systems, effectiveness; prehospital care