title: Risk markers of late high-degree atrioventricular block in patients with left ventricular dysfunction after an acute myocardial infarction: a CARISMA substudy.
abstract: OBJECTIVE
  High-degree atrioventricular block (HAVB) after acute myocardial infarction (AMI) is associated with increased risk of mortality. Risk markers and predictors of HAVB occurring after AMI are largely unknown. The aim of this study was to assess the predictive value of risk markers derived from a series of non-invasive and invasive tests for the development of HAVB documented by an implantable loop recorder (ILR) in late convalescent phases of an AMI.
  
  
  RESULTS
  The study included 292 patients with AMI and subsequent left ventricular dysfunction without prior HAVB or implanted pacemaker. An ILR was implanted for continuous arrhythmia surveillance. Risk stratification testing was performed at inclusion and 6 weeks after AMI. The tests included echocardiography, electrocardiogram (ECG), 24 h Holter monitoring, and an invasive electrophysiological study. High-degree atrioventricular block was documented in 28 (10%) patients during a median follow-up of 2.0 (0.4-2.0) years. Heart rate variability (HRV) measures and non-sustained ventricular tachycardia occurring at the week 6 Holter monitoring were highly predictive of HAVB. Power law slope <-1.5 ms(2)/Hz was the most powerful HRV parameter (HR = 6.02 [2.08-17.41], P < 0.001).
  
  
  CONCLUSIONS
  Late HAVB development in post-AMI patients with left ventricular dysfunction can be predicted by risk stratification tests. Measures of HRV reflecting autonomic dysfunction revealed the highest predictive capabilities.
authors.affiliation: Department of Cardiology, Gentofte University Hospital, Copenhagen, Denmark. dr.gang@dadlnet.dk
authors.forename: Uffe Jakob Ortved
authors.initials: UJ
authors.lastname: Gang
authors.forename: Christian
authors.initials: C
authors.lastname: Jøns
authors.forename: Rikke Mørch
authors.initials: RM
authors.lastname: Jørgensen
authors.forename: Steen Zabell
authors.initials: SZ
authors.lastname: Abildstrøm
authors.forename: Marc D
authors.initials: MD
authors.lastname: Messier
authors.forename: Jens
authors.initials: J
authors.lastname: Haarbo
authors.forename: Heikki V
authors.initials: HV
authors.lastname: Huikuri
authors.forename: Poul Erik Bloch
authors.initials: PE
authors.lastname: Thomsen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D054537:Atrioventricular Block / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology*; D015716:Electrocardiography, Ambulatory; D005260:Female; D005500:Follow-Up Studies; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D015994:Incidence; D053208:Kaplan-Meier Estimate; D008297:Male; D009203:Myocardial Infarction / Q000150:complications*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012307:Risk Factors; D017180:Tachycardia, Ventricular / Q000175:diagnosis / Q000503:physiopathology; D018487:Ventricular Dysfunction, Left / Q000209:etiology* / Q000503:physiopathology*