Key Points
- Identify the underlying electrophysiological mechanism of sustained ventricular tachycardia mimicking supraventricular tachycardia in a patient with intraventricular conduction delay.
- Evaluated a 35-year-old male presenting with sustained regular tachycardia exhibiting right bundle branch block morphology.
- Conducted invasive electrophysiological testing and evaluated baseline resting electrocardiograms before and after arrhythmia episodes.
- Electrophysiological testing induced dual-direction tachycardias via clockwise and counterclockwise bundle branch reentry, manifesting as right and left bundle branch block morphologies.
- Spontaneous tachycardia episodes ceased following the resolution of the resting right bundle branch block, indicating that delayed conduction in the right bundle branch was essential to sustaining the reentrant circuit.
Structured PICO
PPopulation1 adult male (35 years old) presenting with regular tachycardia with right bundle branch block morphology
IInterventionElectrophysiological testing
OOutcomeIdentification of tachycardia mechanism
Bundle branch reentry can manifest as both clockwise and counterclockwise circuits, masquerading as supraventricular tachycardia, with slow conduction in the right bundle branch playing an essential role.