title: Predictive accuracy of electrophysiologic localization of accessory pathways.
abstract: Operative ablation of accessory pathways depends critically on preoperative localization when technical limitations preclude complete intraoperative mapping. To assess the accuracy of localization, 345 patients undergoing operative ablation were studied; 316 (91.6%) had a single accessory pathway and 29 (8.4%) had multiple accessory pathways. The electrophysiologic study was diagnostically complete and accurate in 294 patients (93%) with a single accessory pathway and 19 (61%) with multiple accessory pathways. A left lateral accessory pathway was most accurately localized with excellent sensitivity (99%) and positive predictive value (98.5%). Diagnostic errors occurred in 33 patients because of 1) incorrect localization (n = 16), 2) failure to detect a second pathway (n = 9), and 3) diagnosis of a second pathway not verified intraoperatively (n = 8). Multiple pathways were more prevalent in the group with errors (33.3% vs. 5.8%, p = 0.0001), as were unidirectional pathways (48.5% vs. 24.3%, p = 0.003). It is concluded that preoperative localization of accessory pathways is sufficiently accurate to allow intraoperative mapping to be brief and focused.
authors.affiliation: Department of Medicine, University Hospital, London, Ontario, Canada.
authors.forename: W S
authors.initials: WS
authors.lastname: Teo
authors.forename: G J
authors.initials: GJ
authors.lastname: Klein
authors.forename: G M
authors.initials: GM
authors.lastname: Guiraudon
authors.forename: R
authors.initials: R
authors.lastname: Yee
authors.forename: J W
authors.initials: JW
authors.lastname: Leitch
mesh_terms: D000328:Adult; D002304:Cardiac Pacing, Artificial; D004562:Electrocardiography; D004564:Electrocoagulation; D004594:Electrophysiology; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D007430:Intraoperative Care; D008297:Male; D011237:Predictive Value of Tests; D011300:Preoperative Care; D012680:Sensitivity and Specificity; D014927:Wolff-Parkinson-White Syndrome / Q000453:epidemiology* / Q000503:physiopathology / Q000601:surgery