Heart valve disease

The heart valves and what they do

The heart has four chambers (two atria and two ventricles) and four valves, which work like one-way doors:

• The aortic valve separates the left ventricle from the aorta, the main artery of the body;
• The mitral valve separates the left atrium from the left ventricle;
• The tricuspid valve separates the right atrium from the right ventricle;
• The pulmonary valve separates the right ventricle from the pulmonary artery, which carries blood to the lungs.

With each beat, the valves open to let blood move forward and close so it does not flow back. A heart beats about 100,000 times a day, so the valves bear a heavy load for decades. The valves of the left side, the aortic and mitral, are most often affected because they handle the highest pressures.

Three ways a valve can go wrong

• Stenosis (see aortic valve stenosis and mitral valve stenosis): the valve does not open fully and obstructs the flow of blood. The ventricle has to work harder and, over time, its wall thickens.
• Valve insufficiency (regurgitation): the valve does not close completely and some blood leaks backward. The heart has to pump the same blood several times, so the chamber enlarges over time.
• Prolapse: one or both leaflets of the valve (most often the mitral) bulge too far back during closing. It is often mild and harmless; in some patients it comes with regurgitation that needs follow-up.

A valve can have one problem or both at once. Each is graded by severity: mild, moderate or severe. This grade, together with symptoms and the effects on the heart, guides the decision on treatment.

Causes

• Congenital: an aortic valve with two leaflets instead of three (very common, often discovered in adulthood) or other abnormalities present from birth;
• Degenerative: calcification and thickening of the leaflets with age, the most common cause of aortic stenosis in older people;
• Rheumatic heart disease: a consequence of untreated rheumatic fever after a streptococcal sore throat, affecting most often the mitral valve;
• Infective endocarditis: an infection of the valve that can damage it quickly;
• After a heart attack or enlargement of the ventricle, which change the shape of the valve apparatus;
• connective tissue disease, severe hypertension, some medicines and past radiation to the chest.

Symptoms

Valve disease can develop slowly, and the heart compensates for years. So there can be a slow decline in the ability to exert yourself that is mistaken for “age” or “fitness”. Possible signs are:

• dyspnea (difficulty breathing) and fatigue during exertion, later also at rest or lying down;
• chest discomfort or pressure during exertion;
• dizziness or fainting, especially during exertion;
• palpitations and an irregular rhythm;
• edema (swelling) of the ankles and legs, and weight gain from fluid.

Many patients have no symptoms at all, especially at first. Often the first finding is a heart murmur, heard by the doctor with a stethoscope. A murmur does not always mean disease: in children and young people it can be harmless. A new murmur in an adult, however, needs to be clarified with echocardiography.

How the diagnosis is made

The cardiologist starts with the history, the symptoms and listening to the heart. The main test is echocardiography: with ultrasound it shows the leaflets of the valves, how they move, the size of the opening, the direction and severity of any backward leak, and the effects on the chambers and the strength of the heart. Doppler measures the speed and pressure of blood across the valve.

Other helpful tests:

• ECG, for the rhythm (for example atrial fibrillation, frequent in mitral disease) and signs of thickened chambers;
• chest X-ray, when the size of the heart or the lungs needs assessment (a service that may be recommended to you at other centers);
• in selected cases: transesophageal echocardiography, cardiac CT or magnetic resonance imaging, a stress test and coronary angiography, before surgery or when the data are unclear.

For patients with a known valve problem, repeat echocardiography tracks how the disease changes over time.

Not every valve problem needs an intervention

This is one of the most important things for patients to know. Mild changes, without symptoms and without effects on the heart, are followed with periodic check-ups and echocardiography. The interval is set individually: usually every 6 months to a year, and sooner for more significant disease or when the doctor considers it reasonable.

Follow-up has a clear purpose: to find the right time for treatment. In severe disease, the doctor measures not only how severe the valve problem is, but also whether the heart has begun to suffer the consequences or whether symptoms are appearing. The presence of symptoms or damage to the heart is a reason to take a more active decision.

During follow-up it is important to keep blood pressure under control and to treat accompanying conditions. Tell your doctor about any new symptom, even if it seems small.

Treatment

Medicines. They do not “repair” the damaged valve, but they can ease symptoms and treat the consequences: diuretics against swelling and fluid overload, medicines that lower blood pressure and the work of the heart (ACE inhibitors, beta-blockers, as appropriate), medicines to control the rhythm, and anticoagulants when there is atrial fibrillation or a mechanical valve. Patients with rheumatic mitral disease or a mechanical valve take a specific anticoagulant (for example warfarin), because the newer anticoagulants are not suitable for them. Doses are changed only by the doctor.

Repair or replacement. When the disease is severe and there are symptoms or effects on the heart, treatment means an intervention:

• Valve repair preserves the patient’s own valve; when possible (especially for the mitral valve), it is often preferred because it does not require an artificial valve.
• Replacement with a mechanical valve (lasts very long but requires lifelong anticoagulants) or a biological valve (from animal tissue; usually does not require permanent anticoagulation, but can wear out over time and need another procedure). The choice depends on age, other conditions, wish for pregnancy and the patient’s preferences.
• Catheter-based procedures (for example transcatheter aortic valve replacement, TAVR), which do not require opening the chest and are an option for selected patients, according to the heart team’s assessment.

The decision is made by a joint team (cardiologist, cardiac surgeon, anesthesiologist, interventional cardiologist) together with the patient. When an intervention is needed, assessment at a specialized center with wide experience in this field is recommended.

What can happen without follow-up

Severe valve disease that is not followed can lead to heart failure, atrial fibrillation (with a risk of stroke, that is cerebral stroke, from clots), dangerous rhythm disturbances and, in some cases, sudden death. Damaged valves also carry a higher risk of infective endocarditis, which is why oral hygiene and regular dental visits are part of care. These risks fall greatly when the disease is followed and treated on time.

Everyday life, pregnancy and care

• Physical activity: ask your cardiologist. Many patients can walk and do gentle exercise; heavy sports may be limited in severe stenosis or when there are symptoms.
• Pregnancy: some valve diseases (especially severe mitral or aortic stenosis, and mechanical valves) make pregnancy riskier. Talk to your cardiologist before planning.
• Teeth: good oral care. Some patients with an artificial valve or previous endocarditis need an antibiotic before certain dental procedures, as instructed by the doctor.
• Infections: unexplained fever in the weeks after a procedure, or with an artificial valve, needs prompt assessment.
• Always carry your valve card and your list of medicines.

Contact your cardiologist if new symptoms appear, your ability to exert yourself falls, swelling increases, or you have a known valve disease and have not had a check-up within the set time.