C T Tai1, S A Chen, C E Chiang, S H Lee, M S Chang. 1. Division of Cardiology, Department of Medicine, National Yang-Ming University, School of Medicine, Taipei, Taiwan, Republic of China.
Abstract
STUDY OBJECTIVE: To investigate the ECG characteristics, the electrophysiologic properties, and an effective radiofrequency catheter ablation technique in patients with septal accessory pathways. PATIENTS: Forty-six consecutive subjects with septal accessory pathways located in the anteroseptal, midseptal, and para-Hisian areas. DESIGN AND INTERVENTIONS: ECGs obtained during sinus rhythm and orthodromic tachycardia, conduction properties obtained from electrophysiologic study, and results of two different ablation techniques were analyzed. MEASUREMENTS AND RESULTS: (1) Twenty-four (52.2%) had manifest preexcitation and 15 (32.6%) had multiple accessory pathways; (2) midseptal pathways could be differentiated from anteroseptal and para-Hisian pathways by a negative delta wave in lead III and a biphasic delta wave in lead aVF during sinus rhythm, and a negative retrograde P wave in two inferior leads during orthodromic tachycardia; (2) midseptal pathways had better antegrade conduction properties and a significantly higher incidence (61.5%) of inducible atrial fibrillation; (4) radiofrequency catheter ablation using lower energy (20+/-6 W) had a comparable effect to ablation using higher energy (36+/-5 W), but without impairment of atrioventricular (AV) node conduction or development of AV block; and (5) during the follow-up period of 26+/-14 months (range, 5 to 54 months), three (6.5%) patients had recurrence. CONCLUSIONS: Midseptal accessory pathways had ECG and electrophysiologic characteristics that were distinctive from those of anteroseptal and para-Hisian pathways. Catheter ablation of these septal pathways using low radiofrequency energy was safe and effective.
STUDY OBJECTIVE: To investigate the ECG characteristics, the electrophysiologic properties, and an effective radiofrequency catheter ablation technique in patients with septal accessory pathways. PATIENTS: Forty-six consecutive subjects with septal accessory pathways located in the anteroseptal, midseptal, and para-Hisian areas. DESIGN AND INTERVENTIONS: ECGs obtained during sinus rhythm and orthodromic tachycardia, conduction properties obtained from electrophysiologic study, and results of two different ablation techniques were analyzed. MEASUREMENTS AND RESULTS: (1) Twenty-four (52.2%) had manifest preexcitation and 15 (32.6%) had multiple accessory pathways; (2) midseptal pathways could be differentiated from anteroseptal and para-Hisian pathways by a negative delta wave in lead III and a biphasic delta wave in lead aVF during sinus rhythm, and a negative retrograde P wave in two inferior leads during orthodromic tachycardia; (2) midseptal pathways had better antegrade conduction properties and a significantly higher incidence (61.5%) of inducible atrial fibrillation; (4) radiofrequency catheter ablation using lower energy (20+/-6 W) had a comparable effect to ablation using higher energy (36+/-5 W), but without impairment of atrioventricular (AV) node conduction or development of AV block; and (5) during the follow-up period of 26+/-14 months (range, 5 to 54 months), three (6.5%) patients had recurrence. CONCLUSIONS: Midseptal accessory pathways had ECG and electrophysiologic characteristics that were distinctive from those of anteroseptal and para-Hisian pathways. Catheter ablation of these septal pathways using low radiofrequency energy was safe and effective.
Authors: R Kobza; H Kottkamp; C Piorkowski; H Tanner; P Schirdewahn; A Dorszewski; U Wetzel; J-H Gerds-Li; A Arya; G Hindricks Journal: Z Kardiol Date: 2005-03