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What are the four valves of the human heart?

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Illustration of a human heart cross-section showing four chambers-left and right atria and ventricles-with labeled major blood vessels. An inset highlights cardiac muscle tissue, showing myocytes and intercalated disks. — human cardiovascular system The human heart is both a pump and a muscle. Its four chambers move blood efficiently, while cardiac muscle cells joined by intercalated disks synchronize each contraction.

The human heart contains four valves that ensure blood flows in only one direction, preventing backflow. These valves are categorized into two types:12

Atrioventricular valves: These are located between the atria and the ventricles.1
- Tricuspid valve: Situated on the right side of the heart, it consists of three flaps.12
- Mitral valve: Also known as the bicuspid valve, it is located on the left side of the heart and consists of two flaps.12
Semilunar valves: These are pocketlike structures located where the major arteries leave the ventricles.12
- Pulmonary valve: Guards the opening between the right ventricle and the pulmonary artery.1
- Aortic valve: Protects the opening between the left ventricle and the aorta.13