title: Clinical features and in-hospital mortality associated with different types of atrial fibrillation in patients with acute coronary syndrome with and without ST elevation.
abstract: BACKGROUND
  In patients with an acute coronary syndrome (ACS), no conclusive agreement has been reached to date regarding the association between the different types of atrial fibrillation (AF) and the in-hospital mortality risk. We conducted a retrospective cohort study in patients with ACS to determine the prognostic implications of the different types of AF.
  
  
  METHODS
  We analyzed 6705 consecutive patients with ACS admitted to a coronary care unit (CCU), including 3094 with ST segment elevation myocardial infarction (STEMI) and 3611 with non-ST-elevation acute coronary syndrome (NSTE-ACS). We identified the patients with pre-existing AF, new-onset AF at admission, and new-onset AF at the CCU.
  
  
  RESULTS
  The overall incidence of AF was documented in 360 (5.4%) of the patients (STEMI, 5%; NSTE-ACS, 5.6%), 140 (2.1%) of whom had pre-existing AF, and 220 (3.2%) of whom had new-onset AF (AF at admission, 1.3%; AF at the CCU, 1.9%). The patients with AF had high-risk clinical characteristics and developed major adverse events more frequently than did the patients without AF. The unadjusted in-hospital mortality risk was significantly higher in the patients with pre-existing AF (STEMI, 3.79-fold; NSTE-ACS, 3.4-fold) and AF at the CCU (STEMI, 2.02-fold; NSTE-ACS, 8.09-fold). After adjusting for the multivariate analysis, only the AF at the CCU in the NSTE-ACS group was associated with a 4.40-fold increase in the in-hospital mortality risk (odds ratio 4.40, CI 1.82-10.60, p=0.001). In the STEMI group, the presence of any type of AF was not associated with an increased risk of mortality.
  
  
  CONCLUSIONS
  Among the different types of AF in patients with ACS, only the new-onset AF that developed during the CCU stay in patients with NSTE-ACS was associated with a 4.40-fold increase in the in-hospital mortality risk.
authors.affiliation: Coronary Care Unit, National Institute of Cardiology, Mexico City, Mexico. Electronic address: hectorglezp@hotmail.com.
authors.forename: Héctor
authors.initials: H
authors.lastname: González-Pacheco
authors.affiliation: Cardiac Electrophysiology Laboratory, National Institute of Cardiology, Mexico City, Mexico.
authors.forename: Manlio F
authors.initials: MF
authors.lastname: Márquez
authors.affiliation: Coronary Care Unit, National Institute of Cardiology, Mexico City, Mexico.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Arias-Mendoza
authors.affiliation: Coronary Care Unit, National Institute of Cardiology, Mexico City, Mexico.
authors.forename: Amada
authors.initials: A
authors.lastname: Álvarez-Sangabriel
authors.affiliation: Catheterization Laboratory, National Institute of Cardiology, Mexico City, Mexico.
authors.forename: Guering
authors.initials: G
authors.lastname: Eid-Lidt
authors.affiliation: Cardiac Electrophysiology Laboratory, National Institute of Cardiology, Mexico City, Mexico.
authors.forename: Antonio
authors.initials: A
authors.lastname: González-Hermosillo
authors.affiliation: Coronary Care Unit, National Institute of Cardiology, Mexico City, Mexico.
authors.forename: Francisco
authors.initials: F
authors.lastname: Azar-Manzur
authors.affiliation: Coronary Care Unit, National Institute of Cardiology, Mexico City, Mexico.
authors.forename: Alfredo
authors.initials: A
authors.lastname: Altamirano-Castillo
authors.affiliation: Coronary Care Unit, National Institute of Cardiology, Mexico City, Mexico.
authors.forename: José Luis
authors.initials: JL
authors.lastname: Briseño-Cruz
authors.affiliation: Coronary Care Unit, National Institute of Cardiology, Mexico City, Mexico.
authors.forename: Adolfo
authors.initials: A
authors.lastname: García-Martínez
authors.affiliation: Coronary Care Unit, National Institute of Cardiology, Mexico City, Mexico.
authors.forename: Salvador
authors.initials: S
authors.lastname: Mendoza-García
authors.affiliation: Coronary Care Unit, National Institute of Cardiology, Mexico City, Mexico.
authors.forename: Carlos
authors.initials: C
authors.lastname: Martínez-Sánchez
mesh_terms: D054058:Acute Coronary Syndrome / Q000150:complications*; D000368:Aged; D001281:Atrial Fibrillation / Q000150:complications / Q000401:mortality*; D015331:Cohort Studies; D003325:Coronary Care Units; D005260:Female; D017052:Hospital Mortality; D006760:Hospitalization; D006801:Humans; D015994:Incidence; D008297:Male; D008800:Mexico / Q000453:epidemiology; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies
keywords: Acute coronary syndrome; Atrial fibrillation; NSTE-ACS; New-onset atrial fibrillation; STEMI