title: Atrial high-rate episodes predict clinical outcome in patients with cardiac resynchronization therapy.
abstract: OBJECTIVE
  Up to 50% of patients qualified for cardiac resynchronization therapy (CRT) have documented atrial fibrillation (AF) prior to CRT-implantation. This finding is associated with worse prognosis but few studies have evaluated the importance of post-implant device-detected AF. This study aimed to assess the prognostic impact of device-detected atrial high-rate episodes (AHRE), as a surrogate for AF.
  
  
  METHODS
  Data were retrospectively obtained from consecutive patients receiving CRT. Baseline clinical data and data from CRT device-interrogations, performed at a median of 12.2 months after CRT-implantation, were evaluated with regard to prediction of the composite endpoint of death, heart transplant or appropriate shock therapy. Median follow-up time was 51 months post-implant.
  
  
  RESULTS
  The study included 377 patients. Preoperative AF was present in 49% and associated with worse outcome. The cumulative burden of AHRE at 12 months post-implant was an independent predictor of the primary endpoint. During the first 12 months after CRT-implantation, AHRE were detected in 25% of the patients with no preoperative diagnosis of AF. This finding was not associated with worse outcome.
  
  
  CONCLUSIONS
  In CRT recipients, the cumulative burden of AHRE during the first year of follow-up was associated with worse long-term clinical outcome. Prospective trials are needed to determine if a rhythm control strategy is to be preferred in patients with CRT.
authors.affiliation: a Department of Clinical Sciences, Cardiology , Lund University, Arrhythmia Clinic, Skane University Hospital , Lund , Sweden.
authors.forename: Jonatan
authors.initials: J
authors.lastname: Jacobsson
authors.affiliation: a Department of Clinical Sciences, Cardiology , Lund University, Arrhythmia Clinic, Skane University Hospital , Lund , Sweden.
authors.forename: Pyotr G
authors.initials: PG
authors.lastname: Platonov
authors.affiliation: a Department of Clinical Sciences, Cardiology , Lund University, Arrhythmia Clinic, Skane University Hospital , Lund , Sweden.
authors.forename: Christian
authors.initials: C
authors.lastname: Reitan
authors.affiliation: a Department of Clinical Sciences, Cardiology , Lund University, Arrhythmia Clinic, Skane University Hospital , Lund , Sweden.
authors.forename: Jonas
authors.initials: J
authors.lastname: Carlsson
authors.affiliation: a Department of Clinical Sciences, Cardiology , Lund University, Arrhythmia Clinic, Skane University Hospital , Lund , Sweden.
authors.forename: Rasmus
authors.initials: R
authors.lastname: Borgquist
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology*; D058406:Cardiac Resynchronization Therapy / Q000009:adverse effects / Q000401:mortality; D005260:Female; D006325:Heart Atria / Q000503:physiopathology*; D006333:Heart Failure / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D016027:Heart Transplantation; D006801:Humans; D015994:Incidence; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D013548:Sweden / Q000453:epidemiology; D013997:Time Factors; D016896:Treatment Outcome
keywords: Cardiac resynchronization therapy; atrial fibrillation; atrial high-rate episodes; device-diagnostics; long-term prognosis; mortality