title: A novel method to identify the origin of ventricular tachycardia from the left fascicular system.
abstract: BACKGROUND
  There are well-described ablation strategies to treat left fascicular tachyarrhythmia (LFTA); however, a method to predict the origin is less well characterized.
  
  
  OBJECTIVE
  The purpose of this study was to predict the origin of LFTAs by measuring the HV interval during normal sinus rhythm (NSR) and LFTAs.
  
  
  METHODS
  A predicted value of the earliest presystolic potential (PP) time was calculated using the HV interval during NSR and LFTAs [(HVNSR+HVLFTA)/2]. The earliest retrograde PP was mapped during LFTAs, and the relationship between the predicted and the mapped value was correlated.
  
  
  RESULTS
  Twenty-one consecutive patients with LFTAs were included in this study. Four patients (19%) had tachycardia originating from the left anterior fascicle; the mean HV interval was 50.3 ± 8.3 and 30.3 ± 11.6 ms during NSR and tachycardia, respectively. The mapped retrograde PP during LFTAs preceded the onset of the surface electrocardiogram by 34 ± 9.4 ms. Seventeen patients (81%) had tachycardia originating from the left posterior fascicle; the mean HV interval was 49.2 ± 4.6 and -4.5 ± 13.6 ms during NSR and LFTAs, respectively. Nineteen patients with successful ablation were analyzed; the mean HV interval was -0.9 ± 16.8 and 49.5 ± 4.6 ms during LFTAs and NSR, respectively. The predicted value was similar to the mapped value (24.4 ± 9.1 ms vs 25.2 ± 8.1 ms; P = .76). The predicted value was well correlated with that from the target site (r = 0.97; P < .001).
  
  
  CONCLUSIONS
  The earliest retrograde PP site for the ablation of LFTAs can be predicted measuring the HV interval during NSR and LFTAs. Successful ablation can be performed during NSR for patients with LFTAs inducible at baseline but noninducible during mapping.
authors.affiliation: Cardiology Division, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China.
authors.forename: Hongwu
authors.initials: H
authors.lastname: Chen
authors.affiliation: Cardiology Division, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China.
authors.forename: Fengxiang
authors.initials: F
authors.lastname: Zhang
authors.affiliation: Cardiology Division, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China.
authors.forename: Bing
authors.initials: B
authors.lastname: Yang
authors.affiliation: Heart Institute, Cedars Sinai Medical Center, Los Angeles, California.
authors.forename: Michael
authors.initials: M
authors.lastname: Shehata
authors.affiliation: Cardiology Division, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China.
authors.forename: Weizhu
authors.initials: W
authors.lastname: Ju
authors.affiliation: Cardiology Division, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Yang
authors.affiliation: Cardiology Division, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Gu
authors.affiliation: Cardiology Division, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China.
authors.forename: Mingfang
authors.initials: M
authors.lastname: Li
authors.affiliation: Cardiology Division, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China.
authors.forename: Kejiang
authors.initials: K
authors.lastname: Cao
authors.affiliation: Cardiology Division, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China. Electronic address: chenminglong@njmu.edu.cn.
authors.forename: Minglong
authors.initials: M
authors.lastname: Chen
authors.affiliation: Heart Institute, Cedars Sinai Medical Center, Los Angeles, California.
authors.forename: Xunzhang
authors.initials: X
authors.lastname: Wang
mesh_terms: D000293:Adolescent; D000328:Adult; D002036:Bundle of His / Q000000981:diagnostic imaging* / Q000503:physiopathology; D017115:Catheter Ablation / Q000379:methods; D002648:Child; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D011690:Purkinje Fibers / Q000000981:diagnostic imaging* / Q000503:physiopathology; D017180:Tachycardia, Ventricular / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery; D013997:Time Factors; D055815:Young Adult
keywords: Fascicle; Idiopathic; Left; Predictive; Ventricular arrhythmia