title: Radiofrequency catheter ablation for atrial tachycardia originating from the left atrial appendage.
abstract: A 36-year-old woman presented with drug-refractory atrial tachycardia. During the tachycardia episodes, P waves were positive in leads II, III, aVF, and V1, while they were negative in leads I and aVL. It was hard to determine whether the origin was the left atrial appendage or left superior pulmonary vein on the surface electrocardiogram. Electrophysiologic evaluation revealed that the earliest endocardial activation occurred at the base of the left atrial appendage, preceding the onset of P waves by 38 ms. On initiation of the tachycardia, a warm-up phenomenon was observed. There was a fixed relation between the coupling interval of a single extrastimulus and the return cycle length during the tachycardia. These findings suggested that the mechanism of the tachycardia was automaticity. Application of radiofrequency energy at the left atrial appendage terminated the tachycardia and it was not inducible after ablation.
authors.affiliation: Department of Cardiovascular Medicine, Tottori University Faculty of Medicine, Nishimachi 36-1, Yonago 683-8504, Japan.
authors.forename: Masaru
authors.initials: M
authors.lastname: Kato
authors.forename: Masamitsu
authors.initials: M
authors.lastname: Adachi
authors.forename: Akio
authors.initials: A
authors.lastname: Yano
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Inoue
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Ogura
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Iitsuka
authors.forename: Osamu
authors.initials: O
authors.lastname: Igawa
mesh_terms: D000328:Adult; D020517:Atrial Appendage / Q000503:physiopathology / Q000601:surgery*; D017115:Catheter Ablation; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology / Q000601:surgery; D006801:Humans; D013612:Tachycardia, Ectopic Atrial / Q000503:physiopathology / Q000601:surgery*