Valvular heart disease

Valvular heart disease refers to problems with the valves of the heart. The heart has four valves—the aortic, mitral, pulmonic, and tricuspid valves—that help control the flow of blood. These valves can sometimes stop working properly because of aging, being born with a heart condition, or certain illnesses like rheumatic heart disease.

When a heart valve doesn’t work right, it can make the heart less efficient. Doctors can often treat these problems with medicine. In more serious cases, they might need to fix or replace the valve during surgery, which can help the heart work better again. Understanding how these valves function is important for keeping the heart healthy.

Classification

Valvular heart disease refers to problems with the heart's valves, which help control the flow of blood. The main issues are stenosis, where a valve narrows and restricts blood flow, and insufficiency (or regurgitation), where a valve doesn't close properly and allows blood to flow backward.

The aortic and mitral valves, found on the left side of the heart, are more commonly affected than the pulmonary and tricuspid valves on the right side. This is because the left side of the heart deals with higher pressure. For example, aortic stenosis happens when the valve thickens and makes it hard for blood to leave the heart, often due to aging or birth defects. Aortic insufficiency occurs when the valve doesn't close well, sometimes because of diseases affecting the heart's structure.

Mitral stenosis, which narrows the mitral valve, is often caused by disease from old infections. Mitral insufficiency can happen when the heart stretches and moves the parts that control the valve.

Pulmonary and tricuspid valve problems are less common, especially in adults. Pulmonary valve stenosis is usually present from birth and may become worse with age. Pulmonary insufficiency is often mild and not a problem unless caused by medical procedures or other diseases. Tricuspid stenosis is rare and usually linked to birth defects or other conditions, while tricuspid insufficiency can occur when the right side of the heart stretches.

Signs and symptoms

People with aortic stenosis might feel short of breath when doing things, feel pressure in their chest, or suddenly lose consciousness. Doctors might hear certain sounds in the heart when listening with a stethoscope.

Those with aortic regurgitation can also feel short of breath and pressure in the chest. In sudden cases, they might look pale and feel weak.

People with mitral stenosis may get short of breath, feel fluttering in their chest, or have pain. Doctors often hear loud sounds in the heart when listening with a stethoscope.

Those with mitral regurgitation might feel short of breath and have fluid build-up in their lungs. Doctors might hear specific sounds in the heart when listening with a stethoscope.

People with tricuspid regurgitation often have swelling in their legs, belly, or liver area and might feel pressure in their neck veins. Doctors might hear certain sounds in the heart when listening with a stethoscope.

Causes

Calcification of the aortic valve leaflets is common as people get older. This happens mostly because of extra fats and inflammation in the body, not just because of aging. It is the main reason for a condition called aortic stenosis, especially in people with a certain type of aortic valve. Conditions like high blood pressure, diabetes, high cholesterol, and kidney problems can make this happen faster.

Some heart valve problems are present from birth. For example, tetralogy of Fallot is a birth defect that affects the pulmonary valve, and Ebstein's anomaly affects the tricuspid valve. Having a bicuspid aortic valve, which has two pieces instead of three, is also a birth condition that can lead to problems later in life.

Certain diseases of the body's connective tissues, like Marfan's Syndrome, can also cause heart valve issues. Inflammation of the heart valves, known as valvular endocarditis, can be due to infections, cancer, or autoimmune diseases. One major cause of valve problems is rheumatic heart disease, which follows a throat infection caused by bacteria. This can badly damage the mitral valve, and sometimes the aortic valve too. While this was common in the past, better medicine and living conditions have reduced it in many places. However, it still affects many people in some developing countries.

Diagnosis

Aortic stenosis

People with aortic stenosis might sometimes show changes on a chest X-ray, like a bigger space around the heart, but often the X-ray looks normal. Special tests like ECG can show changes in the heart’s muscles. The best test is an echocardiogram, which shows details like calcium build-up and how the heart valves are working.

Aortic regurgitation

A chest X-ray might not always show problems, but sometimes it can show changes in the heart’s structure. An ECG can show changes in the heart’s muscles, and an echocardiogram is helpful to see what is causing the problem. This test shows how well the heart is pumping and can detect backward flow of blood.

Mitral stenosis

A chest X-ray often shows a larger left atrium and sometimes bigger blood vessels in the lungs. An ECG can show changes in the left atrium. An echocardiogram helps to measure how narrow the valve is and can show calcium build-up and pressure differences across the valve.

Mitral regurgitation

A chest X-ray might show a larger left atrium and congestion in the lung’s blood vessels. It can also show calcium build-up in certain cases. An ECG often shows changes in the left atrium and sometimes the right atrium. An echocardiogram is useful to see the backward flow of blood and to check the valve’s condition. Severe cases need closer monitoring with echocardiograms every few months.

Epidemiology

In the United States, about 2.5% of people have moderate to severe problems with their heart valves. As people get older, these problems become more common. For example, about 13% of people who are 75 years old or older have such issues.

In some parts of the world where industries are not very developed, a specific heart condition called rheumatic heart disease is the main reason for valve problems. It can cause up to 65% of these issues in those areas.

Mitral stenosis is mainly caused by rheumatic heart disease and happens in about 0.1% of people in the United States. It is also the most common valve problem during pregnancy.

Special populations

Pregnancy

When someone with heart valve problems becomes pregnant, there are special things doctors need to watch for. Pregnancy makes the body work harder, with more blood flowing through the heart. This can be tough on the heart, especially if there are problems with the valves.

Doctors pay close attention to certain heart valve issues during pregnancy because they can be risky for both the mother and the baby. These include severe narrowing or leaking of the heart valves, and conditions that put extra strain on the heart. Careful planning and monitoring are important to keep everyone safe.