Atrial flutter with alternating tachycardia cycle length after atrial fibrillation ablation

Abstract

The entrainment pacing maneuver does not Introduction Atrial flutter (AFL) observed in the context of atrial fibrillation (AF) ablation is one of the most important proarrhythmic complications. Previous studies have demonstrated the mechanism and the prevalence of AFL after AF ablation. It is well known that gaps in pulmonary vein (PV) isolation or the liner ablation line and the low-voltage area (LVA) cause scars and PV-related AFL. In addition, recent studies have also implicated the epicardial Marshall bundle as a substrate of AFL. Regular tachycardia cycle length (TCL) has always been considered as a regular characteristic of AFL. We herein present an unusual case of AFL with alternating TCL. effectively identify details of AFL with alternating TCL because of its irregularity. Arranging the timing windows in a 3D mapping system according to each TCL is needed to determine the reentry form. Case report A 77-year-old woman was diagnosed with persistent atrial tachycardia (AT) and frequent episodes of palpitation and dyspnea. The patient had undergone PV and superior vena cava isolation; liner ablations including the roof, bottom, mitral isthmus (MI), and cavotricuspid isthmus line; and left atrial (LA) anterior LVA ablation for persistent AF in 2 ablation procedures 6 years ago. At the time of her third admission, 12-lead electrocardiogram showedATwith 2:1 conduction (Figure 1C). A transthoracic echocardiogram showed a normal left ventricular ejection fraction of 72.5% and an LA diameter of 38 mm. The patient