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Published on: June 29, 2022
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
Abstract:
In a 12-year-old girl with history of recurrent palpitation, an ambulatory 24 h Holter electrocardiogram showed a wide QRS complex rhythm with atrioventricular dissociation. During an electrophysiology study, an atriofascicular pathway was diagnosed with an inducible antidromic atrioventricular re-entrant tachycardia. At slower heart rates, the patient had a wide QRS complex escape rhythm similar to the tachycardia and the pre-excited QRS complex morphology. This indicates the presence of pacemaker-like cells in the atriofascicular accessory pathway giving rise to the wide QRS complex escape rhythm at a slower heart rate.
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