Fast pathway ablation in a patient with PR prolongation
Randa Tabbah1, Bernard Abi-Saleh2
1Departement of Cardiology, Holy Spirit University, Beirut, Lebanon.
Pacing and Clinical Electrophysiology : PACE
|June 14, 2020
Summary
Fast pathway ablation is a viable treatment for typical atrioventricular node reentrant tachycardia (AVNRT) in patients with a long PR interval. This approach avoids risks associated with slow pathway ablation in specific patient groups.
Area of Science:
- Electrophysiology
- Cardiology
- Cardiac Arrhythmias
Background:
- Typical atrioventricular node reentrant tachycardia (AVNRT) usually involves slow-fast pathways, with slow pathway ablation as standard therapy.
- Patients with long PR intervals or reliance on the slow pathway require alternative ablation strategies to prevent atrioventricular block.
Observation:
- A 42-year-old female with restrictive cardiomyopathy and prior ablations presented with incessant narrow complex tachycardia suggestive of AVNRT.
- Baseline EKG showed a prolonged PR interval (320 ms), and electrophysiology study revealed no anterograde fast pathway conduction.
Findings:
- Radiofrequency ablation targeting the retrograde fast pathway in the anteroseptal region successfully terminated the tachycardia.
- Post-ablation, anterograde conduction persisted via the slow pathway, and the tachycardia was rendered uninducible.
Implications:
- Fast pathway ablation is an effective alternative for typical AVNRT in patients with prolonged PR intervals or impaired anterograde fast pathway conduction.
- This technique offers a safe and successful treatment option, preserving normal atrioventricular conduction.
- Case highlights the importance of individualized ablation strategies in complex cardiac arrhythmia management.
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