What is the left atrium?
The left atrium is called the left atrium. Gray's Anatomy (1918) describes it as the upper left chamber of the heart.
What it is
- The upper left chamber of the heart.
- Receives oxygenated blood returning from the lungs.
- Passes that blood into the left ventricle.
Where it is
- At the back of the heart.
- Receives the four pulmonary veins.
- Empties into the left ventricle through the mitral valve.
Source:
Last verified: 2026-07-18
- Best Anatomy Answers is an educational reference about human anatomy. It is not medical advice — for any health concern, talk to a licensed medical professional.