title: Discrete prepotential as an indicator of successful ablation in patients with coronary cusp ventricular arrhythmia.
abstract: BACKGROUND
  Although coronary cusp (CC) ventricular arrhythmia (VA) can be treated by catheter ablation, reliable indicators of successful ablation sites have not been fully identified.
  
  
  RESULTS
  This study comprised 392 patients undergoing radiofrequency catheter ablation for outflow tract-VA at 3 institutions from January 2007 to August 2012. The successful ablation site was on the left CC or right CC in 35 (8.9%) of the 392 patients. In 9 (26%) of these 35 patients, a discrete prepotential was recognized, 5 of whom had left CC-VAs and 4 of whom had right CC-VAs. Radiofrequency catheter ablation was successful at the site of the prepotential in all 9 of these patients. The duration of the isoelectric line between the end of the discrete prepotential and the onset of the ventricular electrogram was 27±13 ms. The time from onset of the discrete prepotential at the successful ablation site on the CC to the QRS onset (activation time) was 69±20 ms (range, 50-98 ms). Pace mapping was graded as excellent at the successful ablation site in only 1 patient. No discrete prepotential was recorded in any successful right outflow tract-VA ablation case in this study.
  
  
  CONCLUSIONS
  A discrete prepotential was seen in 9 (26%) of 35 patients with CC-VA. In left and right CC-VA, the site of a discrete prepotential with ≥50 ms activation time may indicate a successful ablation site.
authors: Department of Cardiology, Cardiovascular Center, Tsuchiura Kyodo Hospital, Tsuchiura, Japan.
authors: Hitoshi
authors: H
authors: Hachiya
authors: Yasuteru
authors: Y
authors: Yamauchi
authors: Yoshito
authors: Y
authors: Iesaka
authors: Atsuhiko
authors: A
authors: Yagishita
authors: Takeshi
authors: T
authors: Sasaki
authors: Koji
authors: K
authors: Higuchi
authors: Mihoko
authors: M
authors: Kawabata
authors: Koji
authors: K
authors: Sugiyama
authors: Yasuaki
authors: Y
authors: Tanaka
authors: Shigeki
authors: S
authors: Kusa
authors: Hiroaki
authors: H
authors: Nakamura
authors: Shinsuke
authors: S
authors: Miyazaki
authors: Hiroshi
authors: H
authors: Taniguchi
authors: Mitsuaki
authors: M
authors: Isobe
authors: Kenzo
authors: K
authors: Hirao
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D000328:Adult; D000368:Aged; D001145:Arrhythmias, Cardiac / Q000503:physiopathology* / Q000601:surgery*; D017115:Catheter Ablation; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006352:Heart Ventricles / Q000503:physiopathology* / Q000601:surgery*; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome
keywords: ablation; coronary cusp; discrete prepotential; ventricular arrhythmia