NETTER - Neuroscience Flash Cards

Innervation of the Heart
1. Nucleus of the solitary tract
2. Dorsal vagal nucleus
3. Superior cervical sympathetic trunk ganglion
4. Middle cervical sympathetic trunk ganglion
5. Cervicothoracic (stellate) ganglion
6. Thoracic vagal cardiac branch
7. Cardiac plexus
8. Thoracic sympathetic cardiac nerves
9. Vagus nerves (CN X)
10. Superior cervical vagal cardiac branches
11. Inferior cervical vagal cardiac branches
Comment: Both sympathetic postganglionic noradrenergic and
parasympathetic postganglionic cholinergic nerve fibers innervate
the heart, including the atria, ventricles, sinoatrial node, and the
atrioventricular node and bundle. Sympathetic nerves also distribute
along the great vessels and coronary artery. Sympathetic fibers
increase the force and rate of cardiac contraction, increase cardiac
output, and dilate the coronary arteries. Parasympathetic fibers
decrease the force and rate of cardiac contraction and decrease
cardiac output. Vagal nerve damage may result in sustained
tachycardia. Excessive vagal activity can provoke bradycardia, atrial
fibrillation or flutter, ventricular fibrillation, or paroxysmal tachycardia.
Sympathetic nerve damage results in severe exercise intolerance,
painless myocardial ischemia, possible cardiomyopathy, and on
occasion sudden death.
Regional Neuroscience See book 9.52