The Use of Low-Level Electromagnetic Fields to Suppress Atrial Fibrillation.

BACKGROUND:
Extremely low-level electromagnetic fields (LL-EMF) have been proposed to cause significant changes of neural networks.
OBJECTIVE:
We sought to investigate if LL-EMF can suppress atrial fibrillation (AF).
METHODS:
In 17 pentobarbital anesthetized dogs, bilateral thoracotomies allowed the placement of multi-electrode catheters on both atria and all pulmonary veins (PVs). AF was inducedby rapid atrial pacing (RAP) or programmed atrial extra-stimulation. At baseline and end of each hour of RAP, during sinus rhythm, atrial programmed stimulation gave both effective refractory period (ERP) and the width of the window of vulnerability (WOV).The latter was a measure of AF inducibility. Microelectrodes inserted into the anterior right ganglionated plexi (ARGP) recorded neural firing. Helmholtz coils were powered by function generator inducing an EMF (0.034 μGauss,0.952 Hz). Group-1 (n=7): Application of EMF to both cervical vagal trunks. Group-2: Application of EMF across the chest, so that the heart was centered within the coil (n=10).
RESULTS:
Group-1: EMF induced a progressive increase in AF threshold at all PV and atrial sites (all P<0.05). Group-2: The atrial ERP progressively shortened and the ERP dispersion and WOV progressively increased (p<0.05;compared to baseline values) during 3 hours of RAP then returned toward baseline during 3 hours of combined RAP+EMF (p<0.05, compared to the end of the 3rd-hour of RAP). The frequency and amplitude of the neural activity recorded from the ARGP was markedly suppressed by EMF in both groups.
CONCLUSIONS:
Pulsed EMF applied to the vagal trunks or non-invasively across the chest can significantly reverse AF inducibility.
Copyright © 2014. Published by Elsevier Inc.
KEYWORDS:
Electromagnetic field ; atrial fibrillation ; autonomic nervous system PEMF
PMID: 25533588