Sinoatrial Node

Sinoatrial Node

The Sinoatrial Node (SA node) is a group of cells located in the right atrium of the heart. These cells are responsible for initiating the electrical impulses that dictate the heart rate, making the SA node the natural pacemaker of the heart.

Anatomy

The SA node is located in the superior part of the right atrium, near the opening of the Superior vena cava. It is a crescent-shaped structure that is approximately 15 mm in length and 5 mm in width.

Function

The primary function of the SA node is to generate electrical impulses that initiate the heartbeat. These impulses are generated at a rate that is influenced by the autonomic nervous system, with the sympathetic nervous system increasing the rate and the parasympathetic nervous system decreasing it.

Clinical significance

Dysfunction of the SA node can lead to a number of arrhythmias, including sick sinus syndrome and sinus bradycardia. Treatment for these conditions often involves the implantation of an artificial pacemaker.

See also

• Atrioventricular node
• Cardiac action potential
• Cardiac pacemaker

References

Template:Cardiac anatomy Template:Cardiac electrophysiology

Sinoatrial Node Resources
Need Help Finding a Doctor? Need help finding a doctor or specialist anywhere in the world? Explore our world directory. WikiMD's DocFinder can assist you in locating millions of physicians.	Medical Knowledge Access the latest research - Most recent articles Ongoing trials.

Translate to: East Asian 中文, 日本, 한국어, South Asian हिन्दी, Urdu, বাংলা, తెలుగు, தமிழ், ಕನ್ನಡ,
Southeast Asian Indonesian, Vietnamese, Thai, မြန်မာဘာသာ, European español, Deutsch, français, русский, português do Brasil, Italian, polski