Mitral Valve Stenosis

Mitral valve stenosis is a problem with the heart's mitral valve. Imagine a doorway that lets blood flow through. In mitral stenosis, this doorway is narrowed. This makes it harder for blood to move from the top left chamber of the heart (left atrium) to the bottom left chamber (left ventricle), which is the heart's main pumping area. The image on the left shows a healthy heart, and the image on the right shows a heart with the narrowed mitral valve.

Essentially, the mitral valve, located between the heart's two left chambers, becomes too tight. This narrowing reduces the amount of blood that can flow into the heart's main pumping chamber, the left ventricle.

This narrowing can cause several symptoms. You might feel tired and short of breath, especially during activity. Other possible symptoms include a fast or irregular heartbeat, dizziness, chest pain, or even coughing up blood. Sometimes, people with mitral stenosis don't experience any symptoms at all.

One of the most common causes of mitral valve stenosis is rheumatic fever, a complication of strep throat. While rheumatic fever was once more common, it's now less frequent in the United States.

Treatment for mitral valve stenosis varies depending on the severity of the condition and whether it's getting worse. Sometimes, medication is enough. In other cases, surgery may be necessary to repair or replace the mitral valve. In some mild cases, regular checkups with a doctor might be all that's needed. If mitral valve stenosis isn't treated, it can lead to more serious heart problems, such as heart failure.

Mitral valve stenosis often develops gradually. You might not notice any problems, or you might have very mild symptoms for a long time. These symptoms can appear at any age, even in children.

Common signs of mitral valve stenosis include:

• Shortness of breath: This is especially noticeable when you're active or lying down. Your body needs more oxygen when you're moving around or lying flat, and if your mitral valve isn't working properly, your heart can't deliver enough oxygen-rich blood to your body.

• Feeling tired (fatigue): This is more likely when you're doing more physical activity. The reduced blood flow from a narrowed mitral valve makes it harder for your body to function at its best.

• Swollen feet or ankles: Fluid can build up in your lower body because your heart isn't efficiently pumping blood throughout your body.

• Irregular heartbeat (arrhythmias): Your heart might beat faster, slower, or skip beats. This is because the narrowed valve can disrupt the normal rhythm of the heart's electrical signals.

• Dizziness or fainting: Low blood flow to the brain can cause these symptoms.

• Fluid buildup in the lungs (pulmonary edema): This can cause shortness of breath, coughing, and discomfort.

• Chest discomfort or pain: This can be a sign of a more serious problem.

• Coughing up blood (hemoptysis): This is a serious symptom that needs immediate medical attention.

Symptoms of mitral valve stenosis may worsen when your heart rate increases, such as during exercise or times of stress. Things like pregnancy or infections can also trigger or worsen symptoms.

If you experience chest pain, a fast or irregular heartbeat, or shortness of breath with activity, seek immediate medical attention. Your doctor might recommend seeing a cardiologist (a heart specialist).

If you've been diagnosed with mitral valve stenosis but are currently symptom-free, discuss a regular follow-up schedule with your healthcare team. This will help ensure your condition is monitored and managed effectively.

See a doctor right away if you have chest pain, a fast or irregular heartbeat, or trouble breathing when you're active. These could be signs of a heart problem. Your doctor might recommend seeing a cardiologist, a doctor specializing in heart conditions.

If you've been diagnosed with mitral valve stenosis and aren't experiencing any symptoms, talk to your doctor about how often you should have checkups. Regular checkups are important to monitor your condition and catch any potential issues early.

The human heart has four chambers: two atria (upper chambers) and two ventricles (lower chambers). The atria receive blood coming into the heart, and the ventricles pump blood out. Little gates called valves control the flow of blood through these chambers, making sure it moves in the right direction.

Mitral valve disease happens when the mitral valve, one of the heart's four valves, doesn't work correctly. This valve has flaps that open and close with each heartbeat. If the valve doesn't open or close properly, it can slow down the flow of blood through the heart to the rest of the body.

One type of mitral valve disease is mitral valve stenosis. In this case, the opening of the mitral valve narrows. The heart has to work harder to pump blood through the smaller opening, which can reduce blood flow between the heart's upper and lower left chambers.

Several things can cause mitral valve stenosis:

• Rheumatic fever: This condition, often a complication of strep throat, is a common cause. If rheumatic fever damages the mitral valve, it's called rheumatic mitral valve disease. Symptoms might not show up for many years after the fever.

• Calcium buildup: As people age, calcium deposits can accumulate around the mitral valve. This can make the valve opening narrower. This condition is called mitral annular calcification (MAC). Severe MAC can cause problems similar to mitral stenosis, and it's often difficult to treat even with surgery. People with calcium buildup around the mitral valve sometimes also have problems with the aortic valve, another heart valve.

• Radiation therapy: Radiation treatment for some cancers can sometimes cause the mitral valve to become thicker and stiffer. This damage usually develops 20 to 30 years after the radiation treatment.

• Congenital heart defects: In rare cases, babies are born with a narrowed mitral valve. This is a problem present from birth.

• Other health conditions: Conditions like lupus and other autoimmune diseases can sometimes cause mitral valve stenosis, though this is less common.

Mitral valve stenosis, a narrowing of the mitral valve in the heart, can have several causes. Here are some risk factors:

• Untreated Strep Infections: If you have a strep throat infection (like strep throat or scarlet fever) and don't get it treated properly, it can sometimes lead to rheumatic fever. Rheumatic fever can damage the heart valves, including the mitral valve, increasing the risk of stenosis. While rheumatic fever is less common in developed countries like the United States, it's still a concern in parts of the world where access to healthcare might be limited.

• Age: As people get older, calcium deposits can build up around the mitral valve. This buildup can gradually narrow the valve opening, increasing the risk of stenosis.

• Radiation Therapy: Treatment with radiation therapy, often used to treat cancers, can sometimes cause changes in the structure and shape of the heart's mitral valve. If radiation is directed at the chest area, there's a small chance of developing mitral valve stenosis.

• Drug Use: Using illegal drugs like MDMA (commonly known as Molly or Ecstasy) can increase the risk of problems with the heart valves, including the mitral valve.

• Certain Medications: Some medications, particularly older ones, can increase the risk of heart valve damage. Certain migraine medications containing ergot alkaloids, such as ergotamine, can rarely cause scarring of the heart valves, leading to mitral valve stenosis. Similarly, some older weight-loss medications, like those containing fenfluramine or dexfenfluramine (often marketed as "fen-phen"), have also been linked to heart valve disease and other heart problems. These older medications are no longer available in the United States due to these risks.

Untreated mitral valve stenosis can lead to several serious problems.

Irregular Heartbeats (Arrhythmias): A narrowed mitral valve can disrupt the heart's normal rhythm. This irregular heartbeat is called an arrhythmia. One common type of arrhythmia, atrial fibrillation (AFib), is often caused by mitral valve stenosis. The risk of AFib increases with age and the severity of the narrowing.

Blood Clots: The irregular heartbeats associated with mitral valve stenosis can create conditions where blood clots form within the heart. If a clot travels to the brain, it can cause a stroke.

High Blood Pressure in the Lungs (Pulmonary Hypertension): A narrowed mitral valve can slow or block blood flow through the heart. This reduced blood flow increases pressure in the blood vessels of the lungs (pulmonary arteries). The heart has to work harder to pump blood through these vessels, leading to higher pressure.

Right-Sided Heart Failure: The combined effects of changes in blood flow and increased pressure in the lungs put a strain on the right side of the heart. The heart has to work harder to pump blood to the right side of the heart. This extra effort eventually weakens the heart muscle, leading to right-sided heart failure. This means the right side of the heart can't pump blood effectively, causing a buildup of fluid in the body.

Rheumatic fever is a common cause of mitral valve problems. A narrowed mitral valve (mitral valve stenosis) is a condition where the valve doesn't open fully, making it hard for blood to flow through. The best way to prevent this problem is to prevent rheumatic fever, the illness that often leads to it.

Rheumatic fever is often caused by untreated strep throat infections. Strep throat is a bacterial infection that causes sore throats. It's important to get prompt medical attention for sore throats, especially in children. If a person has strep throat, it's usually easily treated with antibiotics. Taking these antibiotics as directed by a doctor is crucial to prevent the infection from progressing to rheumatic fever and, later, mitral valve problems. Early diagnosis and treatment of strep throat are key to preventing these more serious health issues.

Diagnosing Mitral Valve Stenosis: Understanding the Process

If you're experiencing symptoms that might suggest mitral valve stenosis, a healthcare professional will start by talking to you about your symptoms, medical history, and family medical history. They'll also listen to your heart and lungs using a stethoscope.

Mitral valve stenosis, where the mitral valve opening narrows, often creates an unusual heart sound called a heart murmur. This narrowing can also lead to fluid buildup in the lungs.

To confirm a diagnosis and understand the severity of the problem, several tests are typically performed to examine your heart. These tests can reveal the cause and help determine the best treatment plan.

Types of Tests:

• Echocardiogram: This test uses sound waves to create images of your heart as it beats. It helps confirm mitral stenosis, shows areas with poor blood flow, and reveals changes in the heart valves. Crucially, it helps determine how severe the stenosis is. If your stenosis is very severe, you'll likely need an echocardiogram annually. Less severe cases might only require one every 3 to 5 years. Always discuss the frequency with your doctor.

• Electrocardiogram (ECG or EKG): This simple, painless test records the electrical activity of your heart. Small, sticky sensors are placed on your chest, arms, and legs, connected to a machine that shows the heart's rhythm on a graph.

• Chest X-ray: This shows the condition of your heart and lungs. An enlarged heart can be a sign of heart valve problems.

• Exercise Stress Tests: These tests involve walking on a treadmill or riding a stationary bike while your heart's activity is monitored. This helps doctors see how your heart responds to physical exertion and if valve disease symptoms appear during exercise. If you can't exercise, medications that mimic the effects of exercise might be used.

• Cardiac CT (Computed Tomography): This test uses X-rays to create detailed images of your heart and valves. It's often used to diagnose mitral stenosis not caused by rheumatic fever.

• Cardiac MRI (Magnetic Resonance Imaging): This test uses magnetic fields and radio waves to create detailed images of your heart. It can help determine the severity of mitral valve stenosis.

• Cardiac Catheterization: This test uses a thin, flexible tube (catheter) inserted into a blood vessel, typically in the groin or wrist, and guided to your heart. Dye is injected through the catheter to highlight the heart's arteries on X-rays. This test isn't frequently used for diagnosing mitral stenosis but might be necessary if other tests aren't conclusive.

Staging Heart Valve Disease:

Once a diagnosis of mitral stenosis (or other valve disease) is confirmed, your doctor will likely describe the stage of your disease. This is important because it helps determine the best treatment approach. Staging considers symptoms, the severity of the disease, the structure of the valves, and how blood flows through your heart and lungs.

There are four basic stages:

• Stage A (At Risk): You have risk factors for heart valve disease, but you don't currently have symptoms.

• Stage B (Progressive): You have mild or moderate valve disease but no symptoms.

• Stage C (Asymptomatic Severe): You have severe valve disease, but you're not experiencing any symptoms.

• Stage D (Symptomatic Severe): You have severe valve disease, and it's causing noticeable symptoms.