Introduction: A 13 old girl presented with recurrent wide QRS tachycardia since she was 4.
Methods: An electrophysiologic study was performed.
Results: The electrophysiologic study showed that QRS complexes identical to those of the tachycardia could be elicited with premature atrial extrastimuli but with a shorter atrioventricular (AV) delay when the QRS was wide compared with narrow QRS complexes. The tachycardia was ablated at 9 o'clock on the tricuspid annulus demonstrating the presence of an atriofascicular fiber.
Conclusion: We believe that this atypical behavior can be explained by AV nodal like longitudinal dissociation of a slowly conducting accessory pathway.
Keywords: atypical atriofascicular fiber; longitudinal dissociation; wide QRS tachycardia.
© 2022 Wiley Periodicals LLC.