Right atrium: one of the four chambers of the heart. The right atrium receives blood low in oxygen from the body and then empties the blood into the right ventricle.

    Two diagrams show the position of the heart in the body and a close-up, cross section of a healthy heart. Blood flows normally from the right atrium into the right ventricle.

Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.
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