Idiopathic ventricular arrhythmias arising from the pulmonary artery: prevalence, characteristics, and topography of the arrhythmia origin.
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.
Tada
Hiroshi
H
Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi, Gunma, Japan. tada.h@cvc.pref.gunma.jp <tada.h@cvc.pref.gunma.jp>
Tadokoro
Kazuyoshi
K
Miyaji
Kohei
K
Ito
Sachiko
S
Kurosaki
Kenji
K
Kaseno
Kenichi
K
Naito
Shigeto
S
Nogami
Akihiko
A
Oshima
Shigeru
S
Taniguchi
Koichi
K
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