Atrial Arrhythmias in long-QT syndrome under daily life conditions: a nested case control study

J Cardiovasc Electrophysiol. 2009 Apr;20(4):401-7. doi: 10.1111/j.1540-8167.2008.01339.x. Epub 2008 Oct 27.


Background: The long-QT syndromes (LQTS) are inherited electrical cardiomyopathies characterized by prolonged ventricular repolarization and ventricular arrhythmias. Several genetic reports have associated defects in LQTS-causing genes with atrial fibrillation (AF). We therefore studied whether atrial arrhythmias occur in patients with LQTS under daily-life conditions.

Methods: We systematically assessed atrial arrhythmias in LQTS patients and matched controls using implanted defibrillators or pacemakers as monitors of atrial rhythm in a nested case-control study. Twenty-one LQTS patients (3 male; 39 +/- 18 years old; 18 on beta blocker, ICD therapy duration 6.3 +/- 2.7 years; 4 LQT1, 6 LQT2, 2 LQT3) were matched to 21 control subjects (13 male; 50 +/- 19 years old; 3 on beta blocker; pacemaker therapy duration 8.5 +/- 5.5 years; 19 higher-degree AV block, 2 others). LQTS patients were identified by a systematic search of the LQTS patient databases in Münster and Munich.

Results: One-third (7 of 21) of the LQTS patients developed self-terminating atrial arrhythmias (atrial cycle lengths <250 ms). Only one control patient developed a single episode of postoperative AF (P < 0.05 vs LQTS).

Conclusions: LQTS patients at high risk for ventricular arrhythmias may develop short-lasting atrial arrhythmias under daily-life conditions, suggesting that prolonged atrial repolarization may contribute to the initiation of AF.

Publication types

  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Activities of Daily Living*
  • Adolescent
  • Adrenergic beta-Antagonists / therapeutic use*
  • Adult
  • Aged
  • Aged, 80 and over
  • Atrial Fibrillation / genetics*
  • Atrial Fibrillation / prevention & control
  • Case-Control Studies
  • Child
  • Defibrillators, Implantable*
  • Electrocardiography
  • Female
  • Germany
  • Humans
  • Long QT Syndrome / complications
  • Long QT Syndrome / drug therapy
  • Long QT Syndrome / genetics*
  • Long QT Syndrome / therapy
  • Male
  • Middle Aged
  • Pacemaker, Artificial*
  • Time Factors
  • Treatment Outcome
  • Young Adult


  • Adrenergic beta-Antagonists