Yoshihiro Jinbo, MD; Youichi Kobayashi, MD; Akira Miyata, MD; Kazumi Chiyoda, MD; Haruyuki Nakagawa, MD; Kaoru Tanno, MD; Kouzo Kurano, MD; Shuji Kikushima, MD; Takao Baba, MD; Takashi Katagiri, MD

Abstract
Holter ECG was used to evaluate changes in heart rate variability (HRV), indicators of the autonomic nervous system, and arrhythmia before and after radiofrequency (RF) catheter ablation in patients with symptomatic supraventricular tachycardia. Ablation targets in 43 patients included the atrioventricular (AV) nodal pathway (AVNRT, n=17), a right free wall accessory pathway (n=10), a septal accessory pathway (n=6), and a left free wall accessory pathway (n=10). The High freguency component (0.15 -0.40Hz) or pNN50 of HRV analysis, indicating parasympathetic activity, significantly decreased immediately after RF ablation in the AVNRT and septal accessory pathway groups, but not in the right or left wall groups. In contrast, in all four groups, ventricu-lar premature contractions (VPCs) significantly increased in most of the patients, and ventricular tachycardia occurred in a few of the patients immediately after RF ablation. There was no serious arrhythmia. These alter-ations in HRV analysis and arrhythmia returned to the control level after 1 week or more. VPCs after RF ablation did not consistently increase as a result of the reduced parasympathetic tone activity, but at the lesion near the conduction system, the increase in VPCs was inhibited by higher parasympathetic tone activity, because the parasympathetic nerve fibers and receptors were distributed in these lesions.
(Jpn Circ J 1998; 62: 733- 740)

Key Words: Autonomic nerve; Heart rate variability; Proarrhythmia; Radiofrequency catheter ablation

Mailing address: Yoshihiro Jinbo, MD, Third Department of Internal Medicine, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142, Japan