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Heart Valve Flaps - What Are They? How Do They Work?

Written By: Adam Pick, Patient Advocate, Author & Website Founder
Page Last Updated: May 24, 2025

I just received a question from Laura which asks, "My mom was recently diagnosed with a mitral valve regurgitation problem. During her discussion with the cardiologist, he said that her valve flaps were not closing tightly and causing a leak. What exactly does this mean?"

Understanding heart valve anatomy is critical to better understanding the diagnosis of heart valve disease and the surgical steps required to fix the problem. That is why this question about heart valve flaps is such a great inquiry.

Heart valve flaps are also known as "heart valve leaflets". The flaps, or leaflets, are composed of tissue. The flaps sole purpose is to open-and-close tightly to secure that blood flows through the heart in one direction. Each heart valve has three (3) heart valve flaps, except for the mitral valve which has two (2) heart valve flaps. Below you can see two diagrams of the human heart* with the white valve flaps in the opened and closed position.

Heart valve flaps for the four heart valves - aortic, mitral, tricuspid and pulmonary

When the flaps fail to seal properly, heart valve disease can occur and a symptomatic heart murmur can develop. There are several different types of heart valve disease caused by faulty valve functioning. In some cases, the heart valve flaps can suffer from calcium-deposit build-up, known as valve calcification.

Personally, I suffered from two, heart valve flap issues which triggered severe aortic valve stenosis and my need for aortic valve replacement. My aortic valve was bicuspid AND it was calcified. FYI, here is a picture of a calcified aortic valve (bicuspid). You can see that the aortic valve flaps are fused bicuspid and there are white calcium deposit on the leaflet tissue.

Calcium build-up on bicuspid aortic valve

Bicuspid Aortic Valve With Calcium Deposits

I hope that helps explain more about heart valve flaps.

Written by Adam Pick - Patient & Website Founder

Adam Pick is a heart valve patient and author of The Patient's Guide To Heart Valve Surgery. In 2006, Adam founded HeartValveSurgery.com to educate and empower patients. This award-winning website has helped over 10 million people fight heart valve disease. Adam has been featured by the American Heart Association and Medical News Today.

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