Inferior cervical cardiac nerve

Inferior cervical cardiac nerve

The inferior cervical cardiac nerve is one of the three cardiac nerves that originate from the cervical ganglia of the sympathetic nervous system. It plays a crucial role in the autonomic regulation of the heart.

Anatomy

The inferior cervical cardiac nerve arises from the inferior cervical ganglion, which is also known as the stellate ganglion. This ganglion is located at the level of the seventh cervical vertebra (C7) and the first thoracic vertebra (T1). The nerve descends into the thoracic cavity and contributes to the cardiac plexus, which innervates the heart.

Function

The primary function of the inferior cervical cardiac nerve is to transmit sympathetic signals to the heart. These signals increase the heart rate and the force of cardiac contractions, which are essential during the "fight or flight" response. The nerve fibers release norepinephrine, a neurotransmitter that binds to beta-adrenergic receptors on the heart muscle, leading to increased cardiac output.

Clinical Significance

Damage or dysfunction of the inferior cervical cardiac nerve can lead to various cardiac conditions, including arrhythmias and heart failure. It is also a target for certain medical procedures, such as stellate ganglion block, which is used to manage chronic pain and some cardiac arrhythmias.

Related Structures

• Superior cervical cardiac nerve
• Middle cervical cardiac nerve
• Cardiac plexus
• Sympathetic nervous system
• Stellate ganglion

See Also

• Autonomic nervous system
• Cardiac innervation
• Sympathetic ganglia