Clinical importance of new-onset atrial fibrillation after cardiac resynchronization therapy

Heart Rhythm. 2009 Mar;6(3):305-10. doi: 10.1016/j.hrthm.2008.12.017. Epub 2008 Dec 13.


Background: Data on the occurrence and implications of new-onset atrial fibrillation (AF) following cardiac resynchronization therapy (CRT) are scarce. We studied the incidence of new onset AF in CRT-defibrillator (CRT-D) recipients. The influence of new-onset AF on echocardiographic response to CRT and the rate of adverse events also were evaluated.

Objective: The purpose of this study was to assess the incidence and implications of new-onset AF following CRT.

Methods: The study population consisted of 223 consecutive patients with no history of AF. New-onset AF was defined as atrial high-rate episodes >180 bpm for more than 10 minutes/day as detected by the device. Echocardiography was performed at baseline and after 6 months of biventricular pacing. Long-term events included implantable cardioverter-defibrillator therapy for ventricular arrhythmias, hospitalization for heart failure, and all-cause mortality.

Results: Fifty-five (25%) patients developed new-onset AF during mean follow-up of 32 +/- 16 months. When compared to the patients who maintained sinus rhythm during follow-up, patients who developed AF showed less left ventricular (LV) reverse remodeling (DeltaLV end-systolic volume 37 +/- 53 vs >19 +/- 37 mL, P <.05) and less improvement in LV function (DeltaLV ejection fraction 6.7% +/- 8.9% vs 3.5% +/- 10.3%, P <.05). Importantly, patients who developed AF experienced more appropriate ICD shocks for ventricular arrhythmias, more inappropriate shocks, and more hospitalizations for heart failure.

Conclusion: Recipients of CRT-D who develop new-onset AF show less echocardiographic response to CRT and more cardiac adverse events during long-term follow-up.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Atrial Fibrillation / complications
  • Atrial Fibrillation / diagnostic imaging
  • Atrial Fibrillation / physiopathology
  • Atrial Fibrillation / therapy*
  • Defibrillators, Implantable*
  • Echocardiography
  • Female
  • Heart Failure / complications
  • Humans
  • Male
  • Quality of Life
  • Recurrence
  • Ventricular Function, Left