Macroreentrant scar-mediated atrial tachycardia terminated by a nonpropagated stimulus within a narrow diastolic isthmus: Electroanatomic correlation

Abstract

A 76-year-old woman with coronary artery disease status post coronary artery bypass grafting and paroxysmal atrial fibrillation and flutter status post cavotricuspid isthmus ablation underwent radiofrequency (RF) ablation of recurrent, symptomatic atrial tachycardia (AT) (cycle length [CL] 378 ms). High-density activation mapping using a Biosense Webster (Diamond Bar, CA) PentaRay® catheter revealed a macroreentrant circuit rotating clockwise (right anterior oblique, caudal view) along the right atrial free wall and conducting slowly through a narrow isthmus (zigzag line) (Figure 1A).