Heart anatomy in 3D
The heart is a muscular organ in the middle of the chest, slightly to the left, between the lungs. With two atria, two ventricles and four valves it pumps blood to the lungs and the rest of the body. The heart is enclosed in a sac called the pericardium, and its wall has three layers, from inside out the endocardium, myocardium and epicardium. The heart muscle is supplied by the left and right coronary arteries, which branch from the start of the aorta.
Frequently asked questions
Where is the heart?
The heart is a muscular organ in the middle of the chest, slightly to the left, between the lungs.
What does the heart do?
With two atria, two ventricles and four valves it pumps blood to the lungs and the rest of the body.
Which body system does the heart belong to?
The heart belongs to the cardiovascular system. The cardiovascular system is made up of the heart and the blood vessels: arteries, veins and capillaries.
Which arteries supply the heart muscle?
The left and right coronary arteries, which both branch from the aorta just as it leaves the heart.
Parts of the heart
- Right atrium: The chamber that first receives blood returning from the body.
- Right ventricle: It pumps blood from the right atrium out to the lungs.
- Left atrium: The chamber that receives oxygen-rich blood from the lungs.
- Left ventricle: It pumps blood out to the whole body and has the thickest wall.
- Tricuspid valve: Between the right atrium and ventricle, it keeps blood from flowing back.
- Pulmonary valve: The valve between the right ventricle and the pulmonary artery.
- Mitral valve: Between the left atrium and ventricle, it keeps blood from flowing back.
- Aortic valve: The valve between the left ventricle and the aorta.
- Aorta: The largest artery, carrying blood from the left ventricle to the body.
- Pulmonary trunk: The artery taking blood from the right ventricle to both lungs.
- Superior vena cava: The large vein that returns blood from the upper body to the right atrium. It drains the head, neck, arms and upper chest, and is formed where the left and right brachiocephalic veins join.
- Inferior vena cava: The largest vein in the body. It returns blood from the legs, pelvis and abdomen to the right atrium, running up the right side of the spine and through the diaphragm to reach the heart.
- Brachiocephalic trunk: The first branch of the aortic arch, found on the right side only. It divides into the right common carotid artery and the right subclavian artery.
- Brachiocephalic veins: Paired veins, one on each side at the base of the neck, each formed where the internal jugular and subclavian veins meet. The two join to form the superior vena cava.
- Common carotid arteries: The arteries supplying the head and neck, running up each side of the neck. The right one branches from the brachiocephalic trunk and the left straight from the aortic arch; each divides into the internal and external carotid arteries at the level of the upper border of the thyroid cartilage.
- Subclavian arteries: The arteries passing beneath the collarbones to supply the arms. The right one branches from the brachiocephalic trunk and the left straight from the aortic arch; each becomes the axillary artery past the outer edge of the first rib.
Other organs
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Once the 3D model loads you can turn it and select each part.