title: [Induction of atrial tachyarrhythmia in patients with Wolff-Parkinson-White syndrome with and without spontaneous atrial fibrillation].
abstract: The purpose of this study was to examine the relation between spontaneous atrial fibrillation and the induction of atrial tachyarrhythmias during electrophysiologic study in patients with Wolff-Parkinson-White, with and without atrial fibrillation. Intracavitary electrophysiologic study was performed on 115 patients, 27 with spontaneous atrial fibrillation (group 1), 57 symptomatic due to AV re-entrant tachycardias, without spontaneous atrial fibrillation (group 2) and 31 asymptomatic (group 3). Induction of atrial fibrillation was attempted by using single and double atrial extrastimuli during atrial pacing at 2 different cycle lengths and by incremental atrial pacing (protocol A). When atrial fibrillation was not obtained, atrial bursts were added (protocol B). Atrial fibrillation or flutter were induced in 81% of group 1.54% of group 2 and 55% of group 3 patients (p less than 0.05), using protocol A. They were induced in 100, 75 and 71%, respectively (p = 0.01), with protocol B. Considering only sustained (greater than 1 minute) episodes, atrial fibrillation or flutter were induced in the three groups with protocol A in 74, 33 and 32% of the patients, respectively (p less than 0.001). The difference in the three groups was even greater when atrial fibrillation was considered separately from atrial flutter. The reason for this was that atrial fibrillation was induced in two thirds of group 1 patients, while only about 15% of patients without spontaneous atrial fibrillation had this arrhythmia induced. Our results suggest that the induction of sustained atrial fibrillation is a useful parameter to separate Wolff-Parkinson-White patients with from those without spontaneous atrial fibrillation. Due to the low specificity of the analysis of the shortest R-R interval during induced atrial fibrillation for the identification of the patients at risk of sudden death, the induction of sustained atrial fibrillation could be proposed as an additional parameter. This would improve the specificity of electrophysiologic study.
authors.affiliation: Istituto di Medicina e Chirurgia Cardiovascolare, Università di Torino.
authors.forename: F
authors.initials: F
authors.lastname: Gaita
authors.forename: C
authors.initials: C
authors.lastname: Giustetto
authors.forename: R
authors.initials: R
authors.lastname: Riccardi
authors.forename: L
authors.initials: L
authors.lastname: Mangiardi
authors.forename: A
authors.initials: A
authors.lastname: Brusca
mesh_terms: D000328:Adult; D001281:Atrial Fibrillation / Q000209:etiology* / Q000503:physiopathology; D001282:Atrial Flutter / Q000209:etiology*; D004594:Electrophysiology; D006801:Humans; D008875:Middle Aged; D013611:Tachycardia, Atrioventricular Nodal Reentry / Q000209:etiology* / Q000503:physiopathology; D013617:Tachycardia, Supraventricular / Q000209:etiology*; D014927:Wolff-Parkinson-White Syndrome / Q000503:physiopathology*
vernacular_title: Induzione di tachiaritmie atriali in pazienti con Wolff-Parkinson-White con e senza fibrillazione atriale spontanea.