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Supraventricular Tachycardia and Atrioventricular Block
Duy Thai Nguyen1, Nitish Badhwar
1Division of Cardiology, Section of Cardiac Electrophysiology, University of California-San Francisco, 500 Parnassus Avenue, MU East 4, Box 1354, San Francisco, CA 94143, USA.
Cardiac Electrophysiology Clinics
|August 4, 2017
Summary
Differentiating between atrial tachycardia and atypical atrioventricular nodal reentrant tachycardia (AVNRT) in mid- to long-RP supraventricular tachycardia cases is crucial. Pacing maneuvers can help distinguish these arrhythmias, guiding targeted ablation strategies.
Area of Science:
- Cardiology
- Electrophysiology
- Cardiac Arrhythmias
Background:
- Supraventricular tachycardia (SVT) diagnosis can be challenging.
- Mid- to long-RP interval SVTs include atrial tachycardia (AT), atypical atrioventricular nodal reentrant tachycardia (AVNRT), and atrioventricular reentrant tachycardia (AVRT).
- Spontaneous atrioventricular block aids in excluding AVRT.
Purpose of the Study:
- To review pacing maneuvers for differentiating AT from atypical AVNRT.
- To highlight the diagnostic value of retrograde atrial activation patterns.
- To guide ablation targets in complex SVT cases.
Main Methods:
- Review of case studies involving SVT.
- Application of pacing maneuvers to assess retrograde conduction.
- Analysis of earliest retrograde atrial activation sites.
Main Results:
- Pacing maneuvers can effectively distinguish AT from AVNRT.
- Atypical AVNRT often involves a lower common pathway.
- Earliest retrograde atrial activation near the coronary sinus ostium suggests atypical AVNRT.
Conclusions:
- Distinguishing AT from atypical AVNRT is achievable with specific pacing techniques.
- Identifying the site of earliest retrograde atrial activation is key for successful ablation.
- Targeting the coronary sinus region is effective for atypical AVNRT ablation.
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