Non-Invasive Stimulation of the Median Nerve: Neuromodulation to Reduce Atrial Arrhythmias in Paroxysmal Atrial Fibrillation (The Randomized BEAT-AF Pilot Study)

Background Non-invasive low-level electrical stimulation of the median nerve favorably affects atrial electrophysiology and reduces inflammation. Objective To determine whether a novel wearable home-care neuromodulation device that performs median nerve stimulation (MNS) reduces atrial arrhythmias (AA) and related symptoms. Methods BEAT-AF was a randomized, double-blind, sham-controlled, 12-week pilot study. Patients with a paroxysmal atrial fibrillation (AF) burden of 0.5-25% on ambulatory 14-day ECG (aECG) monitoring were randomized 1:1 to either MNS or Sham, using a wristband-like neuromodulation and ECG monitoring device. Results Among 31 patients (n=15 MNS / n=16 Sham; age 67.3±9.7; 23 M / 8 F; CHA2DS2-VASc 2.6±1.7; median AF burden 4.9% [IQR 5.2%]),immediate pre-/post-treatment ECG recordings demonstrated a 35% reduction in premature atrial contraction (PAC) burden with MNS versus a 7% increase with Sham (p=0.039).Comparing baseline to 12-week 14-day ECGs, PAC burden was reduced by 26.5% (p=0.046) vs a numerical change of +3.94% (p=0.94; Sham, between group p=0.46), and the adjusted median AF burden numerically was reduced by 63% (MNS) vs 4.1% (Sham; p=0.42). By EHRA classification, symptomatology improved with MNS (0.45 vs 0.02 reduction in score; p=0.017), with a 26.3% shift from EHRA Class III to I with MNS) (vs Sham; p=0.048). Conclusions In patients with paroxysmal AF, non-invasive median nerve stimulation reduced PAC burden and improved symptomatology; there was a numerical but non-significant reduction in AF burden. This pilot study sets the stage for future pivotal trials of MNS in AF patients.