title: Idiopathic ventricular arrhythmias arising from the pulmonary artery: prevalence, characteristics, and topography of the arrhythmia origin.
abstract: BACKGROUND
  The characteristics of idiopathic ventricular tachycardias (VTs) or idiopathic premature ventricular contractions (PVCs) arising from the pulmonary artery (PA) have not been sufficiently clarified.
  
  
  OBJECTIVE
  The purpose of this study was to clarify the prevalence, characteristics, and preferential sites of idiopathic VT/PVCs arising from the PA (PA-VT/PVCs).
  
  
  METHODS
  Data obtained from 276 patients with idiopathic VT/PVCs who underwent radiofrequency (RF) catheter ablation were analyzed.
  
  
  RESULTS
  Twelve VT/PVCs (4%) were PA-VT/PVCs, and their onset (34 +/- 14 years) was the youngest among all subgroups. Because those QRS morphologies were similar to VT/PVCs arising from the right ventricular outflow tract (RVOT-VT/PVC) and the earliest ventricular activation was from the RVOT, an initial ablation was performed in the RVOT in all patients. However, RF catheter ablation at the RVOT resulted in a QRS morphology change in all patients, so thereafter PA mapping and ablation was performed. A characteristic potential during sinus rhythm and/or the arrhythmia was recorded at the successful PA ablation site in all patients. A perfect or good pace map was obtained in 7 (70%) of 10 patients. The successful ablation site was the septal side of the PA close to the posterolateral attachment in 9 patients (75%) and the septal side close to the anterior attachment in the remaining 3 (25%). No PA-VT/PVCs recurred during follow-up of 27 +/- 13 months.
  
  
  CONCLUSIONS
  PA-VT/PVCs should always be considered when the ECG suggests RVOT-VT/PVCs and RF catheter ablation in the RVOT results in both a failed ablation and a change in QRS morphology. PA-VT/PVCs often originate from the septal side of the PA.
authors.affiliation: Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi, Gunma, Japan. tada.h@cvc.pref.gunma.jp <tada.h@cvc.pref.gunma.jp>
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tada
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Tadokoro
authors.forename: Kohei
authors.initials: K
authors.lastname: Miyaji
authors.forename: Sachiko
authors.initials: S
authors.lastname: Ito
authors.forename: Kenji
authors.initials: K
authors.lastname: Kurosaki
authors.forename: Kenichi
authors.initials: K
authors.lastname: Kaseno
authors.forename: Shigeto
authors.initials: S
authors.lastname: Naito
authors.forename: Akihiko
authors.initials: A
authors.lastname: Nogami
authors.forename: Shigeru
authors.initials: S
authors.lastname: Oshima
authors.forename: Koichi
authors.initials: K
authors.lastname: Taniguchi
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D017115:Catheter Ablation; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011651:Pulmonary Artery; D017180:Tachycardia, Ventricular / Q000453:epidemiology / Q000503:physiopathology* / Q000601:surgery