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Identification of "substrate fibrillators" and "trigger fibrillators" by pacemaker diagnostics
Alexander Yang1, Jaap Ruiter, Dietrich Pfeiffer
1Department of Cardiology, University of Bonn, Germany. alexander.yang@web.de
Heart Rhythm
|May 30, 2006
Summary
Patients with high premature atrial contraction (PAC) activity before atrial fibrillation (AF) onset have lower AF burden, suggesting they are not ideal candidates for PAC-suppressing pacing algorithms. Trigger fibrillators may benefit from these specific pacing strategies.
Area of Science:
- Cardiology
- Electrophysiology
- Medical Devices
Background:
- The effectiveness of pacing algorithms for maintaining sinus rhythm in patients with paroxysmal atrial fibrillation (AF) is not well understood.
- Identifying specific patient subgroups who respond best to these interventions is crucial for optimizing treatment.
Purpose of the Study:
- To identify patients with distinct onset patterns of paroxysmal atrial fibrillation (AF).
- To correlate premature atrial contractions (PACs) preceding AF episodes with AF burden and duration.
Main Methods:
- 112 patients with paroxysmal AF received dual-chamber pacemakers with diagnostic functions.
- Patients were categorized into three groups based on PAC frequency preceding AF onset: high (Group A), moderate (Group B), and low (Group C).
- Pacemaker diagnostic data were analyzed to assess AF burden, episode frequency, and duration.
Main Results:
- Group A (high PAC activity) demonstrated significantly lower AF burden (4.6%) compared to Groups B (15.8%) and C (15.5%).
- Fewer AF episodes per day were observed in Group A (2.1) versus Group B (3.8).
- Mean AF episode duration was shorter in Group A (11.4 hours) than Group C (41.4 hours).
Conclusions:
- Low PAC activity preceding AF, high AF burden, and long episode duration suggest a "substrate" for fibrillation, potentially limiting pacing algorithm efficacy.
- "Trigger fibrillators" with low AF burden despite high PAC incidence may be the ideal candidates for PAC-suppressing pacing algorithms.
- This classification aids in tailoring pacing strategies for patients with paroxysmal AF.
