title: Left ventricular dyssynchrony in pre-excitation syndrome: effect of accessory pathway location and reversibility after ablation therapy.
abstract: We sought to evaluate the effects and reversibility of different locations of accessory pathways (AP) on left ventricular dyssynchrony (LVdys). The acute and chronic effects of AP were evaluated in a canine model (n = 11) and in patients with pre-excitation syndrome (n = 25). Pre-excitation was simulated in the canine model by applying VDD-type epicardial ventricular pacing near the atrioventricular (AV) groove with 50-ms AV interval after median thoracotomy, at five different sites in each animal. For the simulation of pre-excitation through the septal accessory pathway, right basal septal pacing was performed using a transvenous lead. Left ventricular dyssynchrony was measured by a two-dimensional speckle-tracking technique: before and during pacing in the canine model, and before and within 24 h after the ablation in patients with Wolff-Parkinson-White (WPW) syndrome. In the canine model, the most prominent intraventricular LVdys was observed in left lateral pre-excitation (P < 0.001). In patients with pre-excitation syndrome, LVdys was greatest in patients with left free wall accessory pathways before the ablation (P = 0.013). After catheter ablation, such a difference diminished (P = 0.619). The degree of LVdys was different according to the site of AP in both the acute model and chronic patients, and the most significant LVdys associated with pre-excitation was observed in left lateral AP. Left ventricular dyssynchrony was reversible in patients with WPW syndrome. Left ventricular dyssynchrony observed in patients with pre-excitation syndrome might be a different entity from that observed in patients with heart failure.
authors.affiliation: Department of Internal Medicine, Seoul National University Hospital, Seoul National University College of Medicine, 101 Daehang-ro, Jongno-gu, Seoul, 110-744, Korea.
authors.forename: Hyo Eun
authors.initials: HE
authors.lastname: Park
authors.forename: Sung-A
authors.initials: SA
authors.lastname: Chang
authors.forename: Ji-Hyun
authors.initials: JH
authors.lastname: Kim
authors.forename: Il-Young
authors.initials: IY
authors.lastname: Oh
authors.forename: Eue-Keun
authors.initials: EK
authors.lastname: Choi
authors.forename: Seil
authors.initials: S
authors.lastname: Oh
mesh_terms: D058606:Accessory Atrioventricular Bundle / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D000328:Adult; D000818:Animals; D017115:Catheter Ablation; D004195:Disease Models, Animal; D004285:Dogs; D015150:Echocardiography, Doppler; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006801:Humans; D008297:Male; D011226:Pre-Excitation Syndromes / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D020127:Recovery of Function; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D016277:Ventricular Function, Left; D014927:Wolff-Parkinson-White Syndrome / Q000150:complications / Q000503:physiopathology / Q000601:surgery