This Article Full Text Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Chiang, C.-E. Articles by Chang, M.-S. Search for Related Content PubMed PubMed Citation Articles by Chiang, C.-E. Articles by Chang, M.-S.

(Circulation. 1996;93:982-991.)
© 1996 American Heart Association, Inc.

Articles

Prediction of Successful Ablation Site of Concealed Posteroseptal Accessory Pathways by a Novel Algorithm Using Baseline Electrophysiological Parameters

Implication for an Abbreviated Ablation Procedure

Chern-En Chiang, MD; Shih-Ann Chen, MD; Ching-Tai Tai, MD; Tsu-Juey Wu, MD; Shih-Huang Lee, MD; Chen-Chuan Cheng, MD; Chuen-Wang Chiou, MD; Kuo-Chang Ueng, MD; Zu-Chi Wen, MD; Mau-Song Chang, MD

From the Division of Cardiology, Department of Medicine, National Yang-Ming University, School of Medicine, and Veterans General Hospital-Taipei, Taiwan, ROC.

Correspondence to Shih-Ann Chen, MD, Director of Electrophysiology, Division of Cardiology, Veterans General Hospital-Taipei, 201 Sec 2, Shih-Pai Rd, Taipei, Taiwan, ROC.

Background Radiofrequency catheter ablation of concealed posteroseptal accessory pathways (APs) has been a relatively difficult task for electrophysiologists. Without a detailed mapping procedure, the left versus the right posteroseptal AP could not be distinguished. We investigated the electrophysiological characteristics of concealed posteroseptal APs and defined criteria from baseline parameters to predict the successful ablation site. Validity of the criteria was prospectively verified.

Methods and Results Eighty-nine consecutive patients with a single concealed posteroseptal AP underwent successful radiofrequency catheter ablation. Of the initial 48 patients (group 1), the right posteroseptal area was first mapped. If no ideal electrogram could be obtained, or after several ineffective radiofrequency pulses, the left posteroseptal area was then mapped. Special attention was paid to the stability of the coronary sinus catheter with the most proximal electrode straddling the ostium, verified by coronary sinus venography, in all patients. Six patients (12.5%) had the earliest retrograde atrial activation at the middle electrode of the coronary sinus catheter, and successful ablation could only be achieved at the left posteroseptal area. For patients who presented with the earliest atrial activation at the proximal electrode, the presence of long RP' tachycardia suggested a right endocardial approach, while the VA (defined as the difference in the VA intervals between that recorded at the His bundle catheter and that at one of the electrode groups recording the earliest atrial activation) 25 ms during tachycardia suggested a left endocardial approach. The subsequent 41 patients (group 2) were randomized into two subgroups. The initial mapping site was guided by the algorithm in group 2B, while it was not in group 2A. The successful ablation site could be predicted accurately in 18 (90%) of the 20 patients in group 2B. The radiofrequency pulses, ablation time, and fluoroscopic time were markedly reduced in group 2B, mainly because of the omission of unnecessary mapping procedure in the right posteroseptal area in patients with "left atrio–left ventricular" fibers.

Conclusions By the algorithm based on baseline electrophysiological parameters, the successful ablation site could be accurately predicted in a majority of patients with concealed posteroseptal APs. Radiofrequency pulses, ablation time, and fluoroscopic time were markedly reduced.

Key Words: catheter ablation • electrophysiology

This article has been cited by other articles:

				W.-C. Yu, S.-A. Chen, C.-T. Tai, A.-N. Feng, and M.-S. Chang Effects of Different Atrial Pacing Modes on Atrial Electrophysiology : Implicating the Mechanism of Biatrial Pacing in Prevention of Atrial Fibrillation Circulation, November 4, 1997; 96(9): 2992 - 2996. [Abstract] [Full Text]