Induced Effects of Transcranial Magnetic Stimulation on the Autonomic Nervous System and the Cardiac Rhythm

Abstract

Several standard protocols based on repetitive transcranial magnetic stimulation (rTMS) have been employed for treatment of a variety of neurological disorders. Despite their advantages in patients that are retractable to medication, there is a lack of knowledge about the effects of rTMS on the autonomic nervous system that controls the cardiovascular system. Current understanding suggests that the shape of the so-called QRS complex together with the size of the different segments and intervals between the PQRST deflections of the heart could predict the nature of the different arrhythmias and ailments affecting the heart. This preliminary study involving 10 normal subjects from 20 to 30 years of age demonstrated that rTMS can induce changes in the heart rhythm. The autonomic activity that controls the cardiac rhythm was indeed altered by an rTMS session targeting the motor cortex using intensity below the subject's motor threshold and lasting no more than 5 minutes. The rTMS activation resulted in a reduction of the RR intervals (cardioacceleration) in most cases. Most of these cases also showed significant changes in the Poincare plot descriptor SD2 (long-term variability), the area under the low frequency (LF) power spectrum density curve, and the low frequency to high frequency (LF/HF) ratio. The RR intervals changed significantly in specific instants of time during rTMS activation showing either heart rate acceleration or heart rate deceleration.

Noninvasive low-frequency electromagnetic stimulation of the left stellate ganglion reduces myocardial infarction-induced ventricular arrhythmia

“…Amounts of studies have shown that high-frequency stimulation increases cortical excitability, whereas low-frequency stimulation decreases neuronal excitability 11 12 . Recently, studies also demonstrated that TMS might affect the cardiac rhythm by modulating the autonomic nervous system 7 . Scherlag et al .…”

“…Transcranial magnetic stimulation (TMS), a neurostimulation and neuromodulation technique based on the principle of electromagnetic induction of an electric field in the brain, has been proposed for treatment of a variety of neurological disorders. Previous studies has shown that TMS might mediate the cardiac rhythm by modulating the autonomic nervous system 7 . Scherlag et al .…”

Safety and tolerability of repeated sessions of deep transcranial magnetic stimulation in obesity

“…An Italian study reported that LF rTMS of the PFC induces a slight parasympathetic activation (highlighted by a significant bradycardia), and no changes in the sympathetic function [ 45 ]. Conversely, HF rTMS producing cortical excitation especially when applied to the primary motor cortex has been supposed to evoke cardiac responses mediated by connections in the brain cortex with the cardiac-related centers of the CNS (e.g., increase in heart rate) [ 46 ]. In our study, contrary to expectations, neither significant changes in blood pressure nor hypertensive crisis were observed in obese patients receiving HF stimulation.…”

A Cross-Recurrence Analysis of the Pupil Size Fluctuations in Steady Scotopic Conditions

“…The IMFs having most of the power in the autonomic frequency band were retained. The IMFs were then aggregated accordingly to the HF (0.15–0.45 Hz) and LF (0–0.15 Hz) ranges related to the parasympathetic and sympathetic systems activity (Cabrerizo et al, 2014; Figure 3). A CRQA was performed (Marwan and Kurths, 2002; Marwan, 2016) to assess the similarity between the dynamics of the parasympathetic and sympathetic processes by comparing the interaction between the LF and the HF components in the phase space.…”