title: Differentiating origins of outflow tract ventricular arrhythmias: a comparison of three different electrocardiographic algorithms.
abstract: Our objective is to evaluate the accuracy of three algorithms in differentiating the origins of outflow tract ventricular arrhythmias (OTVAs). This study involved 110 consecutive patients with OTVAs for whom a standard 12-lead surface electrocardiogram (ECG) showed typical left bundle branch block morphology with an inferior axis. All the ECG tracings were retrospectively analyzed using the following three recently published ECG algorithms: 1) the transitional zone (TZ) index, 2) the V2 transition ratio, and 3) V2 R wave duration and R/S wave amplitude indices. Considering all patients, the V2 transition ratio had the highest sensitivity (92.3%), while the R wave duration and R/S wave amplitude indices in V2 had the highest specificity (93.9%). The latter finding had a maximal area under the ROC curve of 0.925. In patients with left ventricular (LV) rotation, the V2 transition ratio had the highest sensitivity (94.1%), while the R wave duration and R/S wave amplitude indices in V2 had the highest specificity (87.5%). The former finding had a maximal area under the ROC curve of 0.892. All three published ECG algorithms are effective in differentiating the origin of OTVAs, while the V2 transition ratio, and the V2 R wave duration and R/S wave amplitude indices are the most sensitive and specific algorithms, respectively. Amongst all of the patients, the V2 R wave duration and R/S wave amplitude algorithm had the maximal area under the ROC curve, but in patients with LV rotation the V2 transition ratio algorithm had the maximum area under the ROC curve.
authors.affiliation: Chao-Yang Hospital, The Heart Center, Capital Medical University, Beijing, China.
authors.forename: Z Y
authors.initials: ZY
authors.lastname: Jiao
authors.affiliation: Chao-Yang Hospital, The Heart Center, Capital Medical University, Beijing, China.
authors.forename: Y B
authors.initials: YB
authors.lastname: Li
authors.affiliation: Chao-Yang Hospital, The Heart Center, Capital Medical University, Beijing, China.
authors.forename: J
authors.initials: J
authors.lastname: Mao
authors.affiliation: FuWai Hospital, Department of Cardiology, CAMS and PUMC, Beijing, China.
authors.forename: X Y
authors.initials: XY
authors.lastname: Liu
authors.affiliation: Chao-Yang Hospital, The Heart Center, Capital Medical University, Beijing, China.
authors.forename: X C
authors.initials: XC
authors.lastname: Yang
authors.affiliation: Department of Cardiology, The Military General Hospital of Beijing PLA, Beijing, China.
authors.forename: C
authors.initials: C
authors.lastname: Tan
authors.affiliation: FuWai Hospital, Department of Cardiology, CAMS and PUMC, Beijing, China.
authors.forename: J M
authors.initials: JM
authors.lastname: Chu
authors.affiliation: Chao-Yang Hospital, The Heart Center, Capital Medical University, Beijing, China.
authors.forename: X P
authors.initials: XP
authors.lastname: Liu
mesh_terms: D000465:Algorithms; D001145:Arrhythmias, Cardiac / Q000209:etiology* / Q000503:physiopathology*; D004562:Electrocardiography; D005260:Female; D006352:Heart Ventricles / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies