Adenosine-Sensitive Focal Reentrant Atrial Tachycardia Originating From the Mitral Annulus-Aorta Junction

Adenosine-sensitive reentrant atrial tachycardia (AT) has been recognized to originate from the confined area of either the right or left atiroventricular nodal regions. We describe a case with adenosine-sensitive focal AT which was successfully ablated at the uncommon focus located at the mitral annulus-aorta junction. The mode of AT initiation during the atrial extrastimulus suggested as the mechanism tachycardia reentry; AT was terminated by a bolus of 2 mg of adenosine 5’-triphosphate. These electrophysiological features are possibly associated with a substrate involved in the mitral annulus-aorta junction with node-like properties that is responsive to adenosine.