Congenitally Closed Tricuspid Annulus Functions as Arrhythmogenic Substrate of Atrial Arrhythmia in Patient with Tricuspid Atresia

An intraatrial reentrant circuit was identified using an electroanatomical mapping system and evaluation of postpacing intervals in a patient with tricuspid annulus. Intraatrial reentrant tachycardia was successfully eliminated on the basis of the interpretation that the reentry circuit depends on a congenitally closed tricuspid annulus. We report that a congenitally closed tricuspid annulus is one of the anatomical obstacles when we consider atrial tachyarrhythmia. (PACE 2010; e1–e3)