Adenosine response to a narrow complex tachycardia: who blinks first?
A 21-year-old woman presented to arrhythmia clinic with episodes of recurrent paroxysmal rapid palpitations. The patient had undergone an electrophysiology study and radiofrequency ablation elsewhere and was subsequently referred to our centre. We found a narrow complex tachycardia of cycle 460 ms length ms which was repeatedly induced with atrial extrastimuli. During the tachycardia, 6 mg intravenous adenosine was given, which led to termination of tachycardia as shown in figure 1. What is the mechanism of the tachycardia?
