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Brain & Heart Autonomic nerve and heart failure

to identify and assess the optimal dose of VNS would be intervention. This discovery opens the prospect of using
necessary in the future. To summarize, there is still a long non-invasive methods to treat individuals with AMI .
[55]
way to go in using VNS to treat cardiovascular disease. Compared to invasive VNS, non-invasive VNS is the more
promising therapeutic alternative, which shows potential
3.2. Non-invasive VNS for greater specificity and improved safety. Nonetheless,
VNS is an invasive neuronal modulation used in additional research is required to evaluate its clinical
cardiovascular disease. Surgical complications and side effectiveness.
effects often and inevitably occur in patients during surgical
implantation of a neurostimulator system . However, 3.3. Optogenetics vagus nerve modulation
[48]
studies have demonstrated that both percutaneous nerve The optogenetics vagus nerve modulation approach
stimulation of the tragus (TNS) and non-invasive VNS utilizes optogenetic methods to stimulate the vagus nerve,
can produce analogous results in treating heart disease facilitating focused communication between neurons and
secondary to dysfunction in the CANS. Furthermore, photosensitive actuators (opsin) for delivering viruses to
it is a promising method for regulating cardiac specific organs, depending on their site of delivery. During
autonomic dystonia manifested by hypersympathetic and preclinical animal studies, viruses were applied to target the
hyposympathetic dysfunction . excitatory opsin found in the peripheral nerves, allowing
[49]
The auricular branch of the vagus nerve, a peripheral for the optical stimulation of specific motor activity [56-58] ,
branch of the vagus nerve found solely in the skin, sends and the inhibitory opsin was utilized to suppress muscle
[60]
its afferent vagus fibers through the jugular ganglion and activity [57,59] and alleviate pain . Adeno-associated virus
terminates at the nucleus tractus solitarii (NTS). The NTS (AAV) is commonly employed in experimental settings as
serves as the central station for autonomic neurons, receiving a vector for optical sensors and actuators, with its targeting
incoming sensory information and activating the caudal specificity being affected by factors such as genetic
ventrolateral medulla and dorsal motor nucleus (DMN) promoters, serotypes of the virus, and tissue/delivery sites.
to regulate neural activity within the autonomic nervous In addition, various gene therapy approaches that rely on
system [50,51] . Enhanced cardiac vagus tone is achieved AAV are currently undergoing assessment in clinical trials
through the transmission of electrochemical signals from involving human participants [61-63] . In their study, Fontaine
the overactive DMN through the bilateral cervical vagus et al. successfully proved the viability of retrograde labeling
nerves to the epicardial ganglion plexus. TNS theoretically in achieving optical neuromodulation targeted toward
regulates the equilibrium of the autonomic nervous system specific organs . However, relevant clinical trials are
[64]
in the heart. Following this, TNS has been progressively currently insufficient, and more verification of its efficacy
implemented in the management of cardiovascular is necessary.
disorders, with experimental research demonstrating
favorable impacts on heart-related circumstances. 3.4. Baroreflex activation therapy (BAT)
Chen et al. conducted research that found that low- By activating physiological reflex pathways, BAT can
level tragus nerve stimulation (LL-TS) can effectively reduce sympathetic cardiac outflow and increase cardiac
suppress canine atrial fibrillation (AF). The clinical studies vagal activity through central inhibition. It has previously
conducted by Stavrakis et al. also acknowledged the efficacy been shown to be safe and efficient when treating refractory
[65]
[52]
of LL-TS . LL-TS has the capability to suppress AF and hypertension , and now researchers are investigating its
reduce the concentrations of inflammatory cytokines effectiveness in addressing autonomic nerve imbalance in
[66]
in individuals with paroxysmal AF diagnosis . The patients with heart failure . BAT is performed by surgically
[53]
findings imply that TNS is a fresh approach to regulating implanting a device similar to a pacemaker that produces
cardiovascular disease through the control of the imbalance pulses and is powered by a battery in the chest wall. Leads
[67]
of cardiac autonomic nerves. The study proved that chronic are then strategically placed in the carotid sinus . The use
intermittent LL-TS could lead to notable reductions in of BAT is an innovative and promising approach that has
infarct size, improvements in ventricular function, and demonstrated its efficacy in treating heart failure patients
positive changes in cardiac remodeling for individuals by reducing sympathetic activity and enhancing cardiac
living with ischemic heart disease . According to the function and quality of life. Moreover, the safety profile of
[54]
research, the use of LL-TS can result in a positive outcome, BAT is considered relatively satisfactory [68,69] . Despite the
as it can alleviate injury caused by the restoration of blood potential benefits of BAT, controversies exist in the fields
flow after a period of reduced blood supply to the heart of health economics, device interaction, and the treatment
muscle in acute myocardial infarction (AMI) patients of heart failure with preserved ejection fraction (HFpEF).
who have undergone primary percutaneous coronary Therefore, it remains to be determined, through further

Volume 1 Issue 2 (2023) 5 https://doi.org/10.36922/bh.0913