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Age related changes in dual AV nodal physiology
A D Blaufox1, J F Rhodes, S B Fishberger
1Jack and Lucy Clark Department of Pediatrics, Mount Sinai Medical Center, New York, New York, USA. BlaufoxA@MUSC.EDU
Pacing and Clinical Electrophysiology : PACE
|May 4, 2000
Summary
Dual atrioventricular nodal physiology is common in children, but atrioventricular nodal reentrant tachycardia is rare. This study found age-related electrophysiological differences in the atrioventricular node, explaining the increased incidence of AVNRT in adolescents.
Area of Science:
- Pediatric Cardiology
- Electrophysiology
- Cardiac Arrhythmias
Background:
- Dual atrioventricular nodal (DAVN) physiology is prevalent in pediatric patients with normal hearts.
- Atrioventricular nodal reentrant tachycardia (AVNRT) is uncommon in childhood but increases with age, becoming the most frequent supraventricular tachycardia (SVT) in adolescence.
Purpose of the Study:
- To investigate age-related electrophysiological responses in pediatric patients with DAVN physiology undergoing ablation for AVNRT.
- To elucidate mechanisms behind the increased incidence of AVNRT in adolescents compared to children.
Main Methods:
- Intracardiac electrophysiological study with programmed atrial and ventricular stimulation in 14 pediatric patients.
- Comparison of electrophysiological parameters between two groups: children (mean age 8.2 years) and adolescents (mean age 16.6 years).
Main Results:
- Adolescents exhibited significantly longer fast pathway effective refractory period (ERP), slow pathway ERP, atrio-Hisian (AH) interval during AVNRT, and AVNRT cycle length compared to children.
- A trend for a longer AH interval at the fast pathway ERP was observed in adolescents.
- No significant difference in retrograde VA conduction was found between the age groups.
Conclusions:
- Age-related differences in atrioventricular nodal electrophysiology exist in pediatric patients with DAVN physiology and AVNRT.
- These findings provide insights into the increasing prevalence of AVNRT with age during childhood and adolescence.
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