A labelled diagram of the human heart
Below is a labelled diagram of the human heart with a detailed
heart diagram. This shows the inside of a normal, healthy, human
The human heart diagram shows a cross-section of a healthy heart
and its inside structures. The blue arrow shows the direction in
which oxygen-depleted blood flows from the body to the lungs. The
red arrow shows the direction in which oxygen-enriched blood flows
from the lungs, supplying oxygen to the rest of the body.
The human heart diagram shows the inside of our heart and how it's
divided into four chambers. The two upper chambers of our heart
are called atria. The atria receive and collect blood.
The two lower chambers of our heart are called ventricles. The ventricles
pump blood out of our heart into the circulatory system to other
parts of our body.
The right and left sides of our heart are divided by an internal wall
of tissue called the septum. The area of the septum that divides the atria
(the two upper chambers of your heart) is called the atrial or interatrial
The area of the septum that divides the ventricles (the two lower chambers
of our heart) is called the ventricular or interventricular septum.
We have also provided a printable detailed human heart
Printable detailed human heart diagram>
The human heart diagram shows our heart's four valves. Shown counter clockwise
in the picture, the valves include the aortic valve, the tricuspid valve,
the pulmonary valve, and the mitral valve.
The arrows in the human heart diagram show the direction that blood flows
through the heart. The light blue arrows show that blood enters the right
atrium of the heart from the superior and inferior vena cavae. From the
right atrium, blood is pumped into the right ventricle.
From the right ventricle, blood is pumped to our lungs through the pulmonary
arteries. The light red arrows show the oxygen-enriched blood coming in
from our lungs through the pulmonary veins into the heart's left atrium.
From the left atrium, the blood is pumped into the left ventricle. The
left ventricle pumps the blood to the rest of our body through the aorta.
For the heart to work properly, our blood must flow in only one direction.
The heart's valves make this possible. Both of our heart's ventricles
have an "in" (inlet) valve from the atria and an "out"
(outlet) valve leading to our arteries. Healthy valves open and close
in very exact coordination with the pumping action of our heart's atria
and ventricles. Each valve has a set of flaps called leaflets or cusps
that seal or open the valves. This allows pumped blood to pass through
the chambers and into our arteries without backing up or flowing backward.
End of detailed diagram of the human heart with a human
heart interior diagram.