title: Left ventricular outflow tract tachycardia originating from the right coronary cusp: identification of location of origin by endocardial noncontact activation mapping from the right ventricular outflow tract.
abstract: Idiopathic left ventricular outflow tract (LVOT) tachycardia has been shown to originate from a supravalvular site in some patients. Considerable attention recently has focused on identifying this variant of LVOT tachycardia on 12-lead ECG. We report the case of 15-year-old boy in whom a noncontact three-dimensional mapping electrode deployed in the right ventricular outflow tract (RVOT) assisted in identifying a supravalvular LVOT tachycardia. Observation of two early breakthrough sites in the RVOT and right ventricular septum suggested a right aortic cusp origin of the tachycardia. Pace mapping in the right aortic cusp identified a successful ablation site.
authors.affiliation: Department of Medicine, University of California, San Diego, USA.
authors.forename: James
authors.initials: J
authors.lastname: Storey
authors.forename: Atsushi
authors.initials: A
authors.lastname: Iwasa
authors.forename: Gregory K
authors.initials: GK
authors.lastname: Feld
mesh_terms: D000293:Adolescent; D018780:Body Surface Potential Mapping / Q000295:instrumentation; D003331:Coronary Vessels / Q000473:pathology*; D004567:Electrodes, Implanted; D004699:Endocardium / Q000473:pathology; D006352:Heart Ventricles / Q000473:pathology; D006353:Heart-Assist Devices; D006801:Humans; D008297:Male; D013610:Tachycardia / Q000209:etiology*; D014694:Ventricular Outflow Obstruction / Q000150:complications*