title: Time course and predictors of autonomic dysfunction after ablation of the slow atrioventricular nodal pathway.
abstract: Withdrawal of parasympathetic tone has been reported after ablation in the posteroseptal right atrium and has been attributed to injury of vagal efferent fibers. The purpose of this study was to assess the time course and predictors of autonomic dysfunction after slow pathway ablation. In 30 patients with AV nodal reentrant tachycardia, time- and frequency-domain measures of heart rate variability (HRV) were measured before, 30 minutes after, and 1 day after slow pathway ablation. There were significant reductions in mean RR interval (724 +/- 163 vs 836 +/- 164 ms, P < 0.05), SD of RR intervals (29 +/- 17 vs 40 +/- 18 ms, P < 0.05), root mean squared difference (15 +/- 8 vs 29 +/- 17 ms, P < 0.05), and high frequency power (4.1 +/- 0.4 vs 4.5 +/- 0.6 log10ms2, P < 0.05) 30 minutes after ablation. However, these parameters returned to baseline 1 day after ablation. Multivariate regression identified isoproterenol dose during the diagnostic study (P = 0.02) and radiofrequency duration (P = 0.02) as statistically significant predictors of heart rate change (R2= 0.45). These findings suggest that changes in autonomic tone after ablation in the posteroseptal right atrium are transitory and resolve within 1 day of the procedure. These short-term changes may be related to procedural variables rather than direct injury to vagal efferent fibers.
authors.affiliation: Department of Medicine, Division of Cardiology, The New York Hospital-Cornell University Medical Center, New York, New York 10021, USA. smarkow@med.cornell.edu
authors.forename: Steven M
authors.initials: SM
authors.lastname: Markowitz
authors.forename: David J
authors.initials: DJ
authors.lastname: Christini
authors.forename: Kenneth M
authors.initials: KM
authors.lastname: Stein
authors.forename: Suneet
authors.initials: S
authors.lastname: Mittal
authors.forename: Sei
authors.initials: S
authors.lastname: Iwai
authors.forename: David J
authors.initials: DJ
authors.lastname: Slotwiner
authors.forename: Bruce B
authors.initials: BB
authors.lastname: Lerman
mesh_terms: D000328:Adult; D001342:Autonomic Nervous System Diseases / Q000175:diagnosis* / Q000503:physiopathology; D002316:Cardiotonic Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics; D017115:Catheter Ablation; D005260:Female; D005500:Follow-Up Studies; D006207:Half-Life; D006339:Heart Rate / Q000187:drug effects / Q000502:physiology; D006801:Humans; D007262:Infusions, Intravenous; D007545:Isoproterenol / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011183:Postoperative Complications / Q000175:diagnosis* / Q000503:physiopathology; D012075:Remission, Spontaneous; D013611:Tachycardia, Atrioventricular Nodal Reentry / Q000503:physiopathology / Q000601:surgery*; D014630:Vagus Nerve / Q000503:physiopathology; D061223:Vagus Nerve Injuries
chemical_list: D002316:Cardiotonic Agents; D007545:Isoproterenol