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Atrioventricular nodal reentrant tachycardia diagnosed by pacemaker electrograms
Christophe d'Ivernois1, Marc Hero, Isaac Sayumwe
1Service de Cardiologie, Hôpital Universitaire Dupuytren, 2 avenue Martin Luther King, 87042 Limoges, France. christophe.divernois@chu-limoges.fr
Summary
Pacemaker electrograms aided diagnosis of atrioventricular nodal reentrant tachycardia in a patient with sinus node dysfunction. Radiofrequency ablation successfully treated the arrhythmia.
Area of Science:
- Cardiology
- Electrophysiology
- Medical Devices
Background:
- Pacemakers and implantable defibrillators record electrograms, crucial for diagnosing arrhythmias.
- Sinus node dysfunction is a common indication for pacemaker implantation.
Observation:
- A patient with a DDD pacemaker for sinus node dysfunction presented with recurrent tachycardia episodes.
- Real-time electrogram analysis during tachycardia onset was performed.
Findings:
- Atrioventricular nodal reentrant tachycardia (AVNRT) was diagnosed using intracardiac electrograms.
- Electrophysiological study confirmed the AVNRT diagnosis.
Implications:
- This case highlights the diagnostic utility of stored pacemaker electrograms.
- Radiofrequency ablation targeting the slow pathway provided a curative treatment for AVNRT.
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