Age and Clinically Actionable Events in Patients With Implantable Loop Recorders: Analysis of Multicenter Loop Recorder Registry

J Cardiovasc Electrophysiol. 2025 Jan;36(1):266-275. doi: 10.1111/jce.16509. Epub 2024 Nov 26.

Abstract

Introduction: Little is known about age and clinical intervention after implantable loop recorder (ILR) insertion. This study investigated the association between age and clinical intervention after ILR implantation.

Methods and results: Data were obtained from a multicenter registry of ILR in Korea (2017-2020, n = 795). ILRs were inserted with indications of unexplained syncope, recurrent palpitation, or cryptogenic stroke. The primary outcome was clinically actionable event that was a composite of the newly detected atrial fibrillation (AF), pacemaker or implantable cardioverter defibrillator (ICD) implantation, catheter ablation, and anticoagulation initiation. The mean age was 64.3 years, and the mean follow-up duration was 20.6 months. Clinically actionable events were observed in 322 (40.5%) patients. Compared to younger age (< 50 years), older age (≥ 50 years) showed higher prevalence of newly detected AF (3.7% vs. 15.8%; p = 0.001), pacemaker implantation (11.2% vs. 21.2%; p = 0.022), and initiation of anticoagulation (3.7% vs. 18.6%; p < 0.001). No significant differences were found in ICD implantation (1.9% vs. 1.3%; p = 0.996) or catheter ablation (3.8% vs. 6.0%; p = 0.512). The older age group more frequently experienced clinically actionable events compared to the younger age group (hazard ratio 2.52, 95% confidence interval: 1.86-3.41; p < 0.001). A significant association was found in the increase of age (per 1-year) and the risk of clinically actionable events (adjusted hazard ratio 1.03, 95% confidence interval 1.02-1.04; p < 0.001).

Conclusion: Advanced age is a significant risk factor for clinical intervention after ILR insertion. ILR should be considered more actively in older patients requiring prolonged rhythm monitoring.

Keywords: age; atrial fibrillation; bradyarrhythmia; implantable loop recorder; tachyarrhythmia.

Publication types

  • Multicenter Study
  • Comparative Study
  • Observational Study

MeSH terms

  • Action Potentials
  • Adult
  • Age Factors
  • Aged
  • Anticoagulants / administration & dosage
  • Anticoagulants / therapeutic use
  • Arrhythmias, Cardiac / diagnosis
  • Arrhythmias, Cardiac / physiopathology
  • Arrhythmias, Cardiac / therapy
  • Atrial Fibrillation / diagnosis
  • Atrial Fibrillation / physiopathology
  • Atrial Fibrillation / therapy
  • Cardiac Pacing, Artificial
  • Catheter Ablation / adverse effects
  • Defibrillators, Implantable*
  • Electrocardiography, Ambulatory* / instrumentation
  • Female
  • Heart Rate
  • Humans
  • Male
  • Middle Aged
  • Pacemaker, Artificial
  • Predictive Value of Tests
  • Prevalence
  • Registries*
  • Republic of Korea / epidemiology
  • Retrospective Studies
  • Risk Assessment
  • Risk Factors
  • Syncope / diagnosis
  • Syncope / physiopathology
  • Syncope / therapy
  • Time Factors
  • Treatment Outcome

Substances

  • Anticoagulants