Mitral Valve Stenosis

Mitral valve stenosis (sometimes called mitral stenosis) is a narrowing or blockage of the mitral valve inside your heart. Over time, this condition can cause heart rhythm problems and a higher risk of stroke. It may lead to heart failure and death.

A narrow mitral valve makes it harder for blood to flow from the left atrium (upper chamber) to the left ventricle (lower chamber) on the left side of your heart. This is because the valve can’t open as much as it should to let blood go through. It’s like a door that can’t open all the way.

Your mitral valve is the first valve that blood passes through after traveling through your lungs to collect oxygen. Getting blood to your left ventricle is important because it sends oxygen-rich blood to all your body’s cells.

Common causes of mitral valve stenosis include an allergic or immune reaction to a bacterial infection and calcification of the valve. Children can also have mitral valve stenosis when they’re born (congenital). It can also happen late in life.

How common is mitral valve stenosis?

Mitral valve stenosis is an uncommon disease, especially in developed countries. It affects about 1 out of every 100,000 people in the U.S. It’s more common in developing countries, especially when there’s limited access to antibiotics and medical care.

Mitral valve stenosis is much more likely to happen in people assigned female at birth (AFAB). In developed countries, people in their 50s and 60s make up the majority of mitral valve stenosis cases. In developing countries, it’s a more common diagnosis in younger adults.

When it happens in infants and children, healthcare providers find most cases before the age of 2. It may also run in families, increasing the risk of having it if one of your relatives also has it.