Pulmonary valve facts for kids
Quick facts for kids Pulmonary valve |
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| A front view of the opened heart. The white arrows show the normal path of blood flow. | |
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| The heart seen from above, showing the four valves. | |
| Latin | valva trunci pulmonalis |
The pulmonary valve is one of the four important valves inside your heart. Think of it as a special one-way door that controls where your blood goes. Its main job is to let blood flow out of the heart's right ventricle (one of the lower chambers) and into the pulmonary artery. This artery carries the blood to your lungs to pick up fresh oxygen.
The valve is made of three small, strong flaps of tissue called cusps. These cusps open and close with every single heartbeat. When the pulmonary valve snaps shut, it helps make part of the "dub" sound in the "lub-dub" heartbeat that a doctor hears with a stethoscope.
Contents
How the Pulmonary Valve Works
The pulmonary valve works automatically to keep blood moving in the right direction. It stops blood from flowing backward into the heart after it has been pumped out.
Opening the Valve
When the right ventricle fills with blood, it squeezes to pump the blood out. This squeeze creates pressure that pushes the three cusps of the pulmonary valve open. This allows blood to rush out of the ventricle and into the pulmonary artery, which leads to the lungs.
Closing the Valve
Once the ventricle is done squeezing, it relaxes, and the pressure inside it drops. The pressure in the pulmonary artery is now higher. This difference in pressure tries to pull blood back into the heart, but this movement catches the cusps and snaps them tightly shut. This action prevents any blood from leaking back into the ventricle.
A Closer Look at the Valve's Parts
The pulmonary valve is located where the right ventricle connects to the pulmonary artery. It is perfectly designed for its job.
The Three Cusps
The valve has three flaps called semilunar cusps because they are shaped like half-moons. These cusps are strong but also flexible. This allows them to open wide when blood is pumped through and then form a tight seal when they close. The images below show what each part of the valve looks like.
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The edges of the valve's flaps (cusps).
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The front flap of the valve.
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The right flap of the valve.
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The left flap of the valve.
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The points where the flaps meet.
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Small bumps on the flaps that help them seal.
Why the Valve is Important for Health
Doctors can learn a lot about your heart by listening to the sounds it makes. The "lub-dub" sound of a heartbeat is created by the four heart valves closing in pairs.
The pulmonary valve closing helps create the "dub" sound. By listening to this sound, a doctor can check if the valve is opening and closing correctly. In some young and healthy people, the sound can change a little bit when they breathe in. This is usually completely normal.
See also
- Heart valve
- Pulmonary atresia
More Images
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The inside of the right side of the heart.
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A diagram of the chest showing the location of the heart and its valves. The pulmonary valve is labeled "P".
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A view of the pulmonary valve.
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Another view of the pulmonary valve's three cusps.
