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Spontaneous automaticity of an atriofascicular accessory pathway
Santosh Kumar Dora1, Jaganmohan A Tharakan, Ajithkumar Valaparambil
1Division of Cardiology Department of Medicine, Cedars-Sinai Medical Center, Los-Angeles, CA 90048, USA. kskdora@hotmail.com
Summary
A 12-year-old girl experienced recurrent palpitations due to an atriofascicular pathway. Pacemaker-like cells in this pathway caused a wide QRS complex escape rhythm, mimicking tachycardia.
Area of Science:
- Cardiology
- Electrophysiology
- Pediatric Cardiology
Background:
- Recurrent palpitations in children warrant thorough investigation.
- Wide QRS complex rhythms can indicate various cardiac conditions, including accessory pathway involvement.
Observation:
- A 12-year-old female presented with recurrent palpitations.
- Ambulatory 24-hour Holter monitoring revealed a wide QRS complex rhythm with atrioventricular dissociation.
Findings:
- Electrophysiology study identified an atriofascicular pathway.
- An inducible antidromic atrioventricular re-entrant tachycardia was observed.
- A wide QRS complex escape rhythm, resembling the tachycardia and pre-excited QRS morphology, occurred at slower heart rates.
Implications:
- The findings suggest the presence of pacemaker-like cells within the atriofascicular accessory pathway.
- These cells can generate a wide QRS complex escape rhythm at slower heart rates.
- This case highlights a unique mechanism of bradycardia in the presence of an accessory pathway.
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