Clinical Electrophysiology -> Atrial Fibrillation & Atrial Flutter: -> Electrocardiography D-PO01 - Featured Poster Session (ID 11) Poster

D-PO01-028 - Low-level Tragus Stimulation Increases Heart Rate Variability In Patients With Paroxysmal Atrial Fibrillation (ID 887)

 E.D. Hummel: Nothing relevant to disclose.


Background: Low-level transcutaneous electrical stimulation of the auricular branch of the vagus nerve at the tragus (LLTS) is a promising therapy for atrial fibrillation (AF). The impact of LLTS on autonomic tone in this patient population remains poorly understood.
Objective: To examine the effect of chronic, intermittent LLTS on heart rate variability (HRV) and diurnal variation of heart rate.
Methods: Patients with paroxysmal AF (pAF) were randomized to LLTS (20Hz, 1mA lower than the pain threshold) using an ear clip attached to the tragus (LLTS, n=26) or ear lobe (sham, n=27) for one hour daily for six months. A two-week heart monitor was performed at baseline and at three- and six-month time points. The standard deviation of average RR intervals (SDARR) during sinus rhythm was calculated as surrogate for HRV. To assess the diurnal variation, average heart rate was calculated in four time periods of the day (midnight - 6am; 6am - noon; noon - 6pm and 6pm - midnight). The primary endpoint of the study was AF burden at six months.
Results: The study cohort included 54 patients with pAF (55% females, mean age 65 years) and structurally normal hearts (mean LV EF 60±9%). At six months, AF burden was significantly lower in the LLTS group compared to the sham group (2% vs. 8%, p=0.01). In follow up, SDARR was significantly higher in the LLTS group compared to the sham group (102.9±8.7 ms vs. 96.4±9.4 ms, respectively, p=0.009). In both LLTS and sham group, heart rate showed a diurnal variation with higher values at 6am - noon, noon - 6pm and 6pm - midnight time points compared to midnight - 6am, but there was no difference between the groups (Figure).
Conclusion: LLTS favorably alters autonomic tone in patients with pAF.