Heart rate variability and inappropriate sinus tachycardia after catheter ablation of supraventricular tachycardia.

Sinus tachycardia has been reported after radiofrequency catheter ablation of supraventricular tachycardia. Frequently, these patients require beta-blocking agents for symptomatic control. The purpose of this study was to evaluate prospectively the incidence of inappropriate sinus tachycardia and heart rate variability after ablation of atrioventricular nodal reentrant tachycardia and accessory pathways. Patients undergoing ablation had 24-h ambulatory monitoring ECG (Holter) performed before the procedure, on the day of the ablation, and 3 months afterwards. There were 170 patients, mean age 48 +/- 23 years; 93 were female. A complete study of the 24-h Holter with analysis of heart rate variability: SD, rMSSD, pNN50, high and low frequency was obtained. There was a low prevalence of inappropriate sinus tachycardia after the ablation procedure (10 of 170 patients: five with four atrioventricular nodal reentry, with posteroseptal accessory pathways and one of the latter following ablation of the left accessory pathway). There was no modification of time and frequency domain parameters of heart rate variability in the remaining patients who underwent radiofrequency ablation. Holter monitoring 3 months after ablation showed that parameters of heart rate and heart rate variability had normalized in patients who had developed inappropriate sinus tachycardia. Inappropriate sinus tachycardia may be initiated by both radiofrequency ablation of atrioventricular nodal reentrant tachycardia and radiofrequency ablation of posteroseptal accessory pathways. Specific damage to the posteroseptal region is responsible for these changes, which usually recover spontaneously after 3 months.