title: Improved Stratification of Autonomic Regulation for risk prediction in post-infarction patients with preserved left ventricular function (ISAR-Risk).
abstract: OBJECTIVE
  To investigate the combination of heart rate turbulence (HRT) and deceleration capacity (DC) as risk predictors in post-infarction patients with left ventricular ejection fraction (LVEF) > 30%.
  
  
  RESULTS
  We enrolled 2343 consecutive survivors of acute myocardial infarction (MI) (<76 years) in sinus rhythm. HRT and DC were obtained from 24 h Holter recordings. Patients with both abnormal HRT (slope < or = 2.5 ms/RR and onset > or = 0%) and abnormal DC (< or =4.5 ms) were considered suffering from severe autonomic failure (SAF) and prospectively classified as high risk. Primary and secondary endpoints were all-cause, cardiac, and sudden cardiac mortality within the first 5 years of follow-up. During follow-up, 181 patients died; 39 deaths occurred in 120 patients with LVEF < or = 30%, and 142 in 2223 patients with LVEF>30% (cumulative 5-year mortality rates of 37.9% and 7.8%, respectively). Among patients with LVEF > 30%, SAF identified another high-risk group of 117 patients with 37 deaths (cumulative 5-year mortality rates of 38.6% and 6.1%, respectively). Merging both high-risk groups (i.e. LVEF < or = 30% and/or SAF) doubled the sensitivity of mortality prediction compared with LVEF < or = 30% alone (21.1% vs. 42.1%, P < 0.001) while preserving 5-year mortality rate (38.2%).
  
  
  CONCLUSIONS
  In post-MI patients with LVEF>30%, SAF identifies a high-risk group equivalent in size and mortality risk to patients with LVEF < or = 30%.
authors.affiliation: Medizinische Klinik und Deutsches Herzzentrum München der Technischen Universität München, München, Germany.
authors.forename: Axel
authors.initials: A
authors.lastname: Bauer
authors.forename: Petra
authors.initials: P
authors.lastname: Barthel
authors.forename: Raphael
authors.initials: R
authors.lastname: Schneider
authors.forename: Kurt
authors.initials: K
authors.lastname: Ulm
authors.forename: Alexander
authors.initials: A
authors.lastname: Müller
authors.forename: Anke
authors.initials: A
authors.lastname: Joeinig
authors.forename: Raphael
authors.initials: R
authors.lastname: Stich
authors.forename: Antti
authors.initials: A
authors.lastname: Kiviniemi
authors.forename: Katerina
authors.initials: K
authors.lastname: Hnatkova
authors.forename: Heikki
authors.initials: H
authors.lastname: Huikuri
authors.forename: Albert
authors.initials: A
authors.lastname: Schömig
authors.forename: Marek
authors.initials: M
authors.lastname: Malik
authors.forename: Georg
authors.initials: G
authors.lastname: Schmidt
mesh_terms: D000368:Aged; D001145:Arrhythmias, Cardiac / Q000209:etiology / Q000503:physiopathology; D001341:Autonomic Nervous System / Q000503:physiopathology; D016757:Death, Sudden, Cardiac / Q000209:etiology / Q000517:prevention & control; D015716:Electrocardiography, Ambulatory / Q000379:methods; D004812:Epidemiologic Methods; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications / Q000503:physiopathology*; D011379:Prognosis; D016277:Ventricular Function, Left / Q000502:physiology*