How does blood circulate into and out of the heart?

Blood enters the heart through veins called the superior and inferior vena cava into the right atrium. The blood passes through the tricuspid valve into the right ventricle, where it is pushed past the pulmonary valves into the pulmonary arteries to the lungs. The blood then comes back to the heart via the pulmonary veins into the left atrium. The blood then passes though the bicuspid valve into the left ventricle, where it is pushed though the aortic valves into the aorta, which carries it to the rest of the body. (This answer provided for NATA by the University of Montana Athletic Training Education Program.)
Dr. Mehmet Oz, MD
Cardiology (Cardiovascular Disease)
Blood from the body enters the heart through the upper right chamber and flows into the lower right chamber, which pumps it to the lungs. It flows back into the upper left chamber and then the lower right chamber, which pumps it back into the body. This animation shows you how this happens.

Continue Learning about Heart and Circulatory System

Heart and Circulatory System

Heart and Circulatory System

Your circulatory system is made up of your heart and three main types of blood vessels -- arteries, veins and capillaries. Your heart is at the center of the system, acting as a pump to distribute nutrient- and oxygen-rich blood t...

hrough your body; it then takes away carbon dioxide and other waste your body doesn't need. Signs of poor circulation include cold hands and feet, numbness, dizziness, migraines, varicose veins and pain in your feet or legs. Untreated, poor circulation can lead to stroke, high blood pressure, kidney damage and other diseases. Learn more about your heart and circulatory system with expert advice from Sharecare.

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.