Review Article
Volume 8 Issue 8 - 2021
The Human Heart as the "Little Brain"—the Intrinsic Cardiac Nervous System (ICNS)
Nicholas A Kerna1,2*, Joseph Anderson II3, John V Flores4,5, Hilary M Holets4,5, Emmanuella O Solomon6, Kevin D Pruitt7,8, ND Victor Carsrud9 and Uzoamaka Nwokorie10
1SMC–Medical Research, Thailand
2First InterHealth Group, Thailand
3International Institute of Original Medicine, USA
4Beverly Hills Wellness Surgical Institute, USA
5Orange Partners Surgicenter, USA
6Obafemi Awolowo University, Nigeria
7Kemet Medical Consultants, USA
8PBJ Medical Associates, LLC, USA
9Lakeline Wellness Center, USA
10University of Washington, USA
*Corresponding Author: Nicholas A Kerna, SMC–Medical Research, Thailand.
Received: August 17, 2021; Published: August 30, 2021




Abstract

The heart is extensively supplied with nerves of the autonomic nervous system (ANS). These nerves allow the brain to have neural control of vital cardiac activity. The sympathetic and parasympathetic branches of ANS act antagonistically to regulate the mechanical and physiological functions of the heart, atrial and ventricular contractions, heartbeat, heart rhythm, blood flow, and blood pressure.

Nerves descending from the brain stem provide a continuous network of cardiac nerves and ganglia disseminated in the atrial and ventricular epicardial of the heart. This extensive system of nerves in the heart, termed the intrinsic cardiac nervous system (ICNS), controls local cardiac activity and is sometimes called the “little brain”. However, the little brain is not solely responsible for the cardiac activity, as is evident in various cardiovascular diseases.

A brain injury can affect heart function, indicating that the brain plays a significant role in modulation heart physiology. A scientific quest that has been continuing for more than a century has unraveled some of the factors responsible for heart functions. In recent years, crosstalk between the little brain and the brain's central nervous system has become a crucial topic of research as scientists have realized its clinical implications.

The high number of deaths from cardiovascular disease has made it imperative to explore this interactive signaling network to develop appropriate therapeutic interventions. In this review, the role played by this second brain is explicated, leading to a greater understanding not only of its function within the heart but also its connection to the human brain.

Keywords: Autonomic Nervous System; Intrinsic Cardiac Nervous System; Neural Crest Cells; Pulmonary; Sympathetic Nervous System

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Citation: Kerna NA, Anderson II J, Flores JV, Holets HM, Solomon EO, Pruitt KD, Carsrud NDV, Nwokorie U. "The Human Heart as the "Little Brain"—the Intrinsic Cardiac Nervous System (ICNS)”. EC Cardiology 8.9 (2021): 26-34.

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