Vagotonia

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Vagotonia is the state of the autonomic nervous system in which there is increased parasympathetic input through the vagus nerve, or the equilibrium between the sympathetic and parasympathetic is biased towards the latter. [1] [2] The opposite phenomenon has been referred to as sympatheticotonia. [2]

Description

Increased parasympathetic outflow prominently affects the heart, reducing the heart rate or, in extreme cases, completely halting heart beats. This is a common cause of fainting. [3]

The parasympathetic nervous system is dominant in situations of rest and relaxation, it has an activating effect on digestive organs and a relieving one on the heart. Endurance training increases vagotonia. For example, a low heart rate may be observed with sportsmen. [4]

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References

  1. Štursová, P; Budinská, X; et al. (December 2023). "Sports Activities and Cardiovascular System Change" (PDF). Physiological Research. 72 (S5): S429–S444. doi:10.33549/physiolres.935238. PMC   10861254 . PMID   38165749 . Retrieved 10 February 2024.
  2. 1 2 Manolis, AA; Manolis, TA; et al. (July 2021). "The role of the autonomic nervous system in cardiac arrhythmias: The neuro-cardiac axis, more foe than friend?". Trends in Cardiovascular Medicine. 31 (5): 290–302. doi:10.1016/j.tcm.2020.04.011. PMID   32434043 . Retrieved 10 February 2024.
  3. Brignole, M; Moya, A; et al. (June 2018). "2018 ESC Guidelines for the diagnosis and management of syncope". European Heart Journal. 39 (21): 1883–1948. doi:10.1093/eurheartj/ehy037 . Retrieved 10 February 2024.
  4. Billman, GE (October 2009). "Cardiac autonomic neural remodeling and susceptibility to sudden cardiac death: effect of endurance exercise training". American Journal of Physiology. Heart and Circulatory Physiology. 297 (4): H1171–H1193. doi:10.1152/ajpheart.00534.2009. PMID   19684184 . Retrieved 10 February 2024.