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Change in cycle length during narrow complex tachycardia: what is the mechanism?
Diego Chemello1, Anandaraja Subramanian, Douglas Ing
1Toronto General Hospital, University Health Network.
Abstract:
Major spontaneous variation in cycle length during supraventricular tachycardia is quite an uncommon phenomenon, which sometimes can mislead a correct diagnosis. We describe a patient who developed spontaneous variation in cycle length during electrophysiologic study in whom the coronary sinus cannulation was extremely difficult. In this situation, careful inspection of the mechanisms associated with this variation and classic pacing maneuvers are important to make a correct diagnosis of the supraventricular tachycardia.
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