Heart valve disease

Normal heart detail

Patient picks for Heart disease

Heart health and blood vessels

Dilated cardiomyopathy causes: what are the risk factors?

Having dilated cardiomyopathy means that your heart muscle is weakened, which affects how your heart pumps blood around your body. There are a wide range of dilated cardiomyopathy causes, including genetics, other health conditions, alcohol consumption and a poor diet. While we can't control some of these risk factors, we can make positive lifestyle changes to reduce our risk of developing dilated cardiomyopathy.

by Amberley Davis

Heart health and blood vessels

Cardiovascular disease

Cardiovascular diseases (CVD) is a general term to describe diseases of the heart or blood vessels. The cause of most cardiovascular disease is a build-up of atheroma - a fatty deposit within the inside lining of arteries. The blood flow to the heart muscle may also be restricted by a blood clot in an artery taking blood to the heart muscle (coronary artery disease). Atheroma or a blood clot may also restrict or prevent blood going to the brain (cerebrovascular disease) or to the legs and feet (peripheral arterial disease). There are lifestyle factors that can be taken to reduce the risk of forming atheroma. These include not smoking; choosing healthy foods; a low salt intake; regular physical activity; keeping your weight and waist size down; drinking alcohol in moderation. Your blood pressure and cholesterol level are also important. All people aged over 40 years should have a cardiovascular health risk assessment - usually available at your GP surgery. If you have a high risk of developing a cardiovascular disease, treatment to reduce high blood pressure (hypertension) and/or cholesterol may be advised.

by Dr Colin Tidy, MRCGP

What is heart valve disease?

A heart valve that is diseased or damaged can affect the flow of blood through the heart. There are two main types of heart valve problem:

• Heart valve stenosis. This means that the opening of the heart valve is narrowed and the valve does not open fully. So, there is some restriction in blood flow through the valve.

• Heart valve regurgitation (sometimes called heart valve incompetence, or a leaky valve). This means that the valve does not close properly and there is backflow of blood through the leaky valve.

Any of the heart valves can be affected by these problems. However, the mitral and aortic valves are the ones that most commonly become diseased. Read more in our separate leaflets on mitral stenosis, mitral regurgitation, aortic stenosis and aortic regurgitation.

What are the symptoms of heart valve disease?

Heart valve disease symptoms may include:

• Shortness of breath. This tends to occur on exercise at first but occurs at rest if the stenosis becomes worse. This symptom is due to the congestion of blood and fluid in the lungs.

• Fainting, dizziness or tiredness. If the amount of blood getting through to the ventricle is reduced, the output of blood from the left ventricle to the body is then reduced.

• Chest pains (angina). This may develop if there is a reduced blood flow to the arteries that take blood to the heart muscle (the coronary arteries).

• Fast or irregular heartbeat which you may feel as the sensation of a 'thumping heart' (palpitations).

• Chest infections may happen more often.

• Coughing up bloodstained sputum. This may occur due to the congestion of blood and fluid in the lungs.

• The liver may be swollen and you may develop a swollen stomach due to fluid.

• People with mitral stenosis may get flushed cheeks.

If rheumatic fever is the cause then symptoms often start between the ages of 20 and 50 years. (That is, 10-20 years after having have had an episode of rheumatic fever as a child.)

What causes heart valve disease?

Degenerative changes

This is one of the most common causes of leaky heart valves. The structures supporting the heart valves weaken and stretch over time and this prevents the valves from closing properly.

Rheumatic heart disease

• Rheumatic heart disease is a general term which means any heart problem which develops after having an episode of rheumatic fever.

• Rheumatic fever is a condition which sometimes follows an infection with a germ (bacterium) called the streptococcus. Your body makes antibodies to the bacterium to clear the infection. But, in some people, the antibodies also attack various parts of the body - in particular, the heart valves. Inflammation of one or more valves may develop which can cause permanent damage and lead to thickening and scarring years later.

• Rheumatic fever used to be common in the UK in the era before antibiotics but it is now rare. It is still quite common in some developing countries.

Other causes of heart valve disease

Other causes of heart valve disease include:

• Deposits of calcium (calcification) in parts of the valve. This is the most common cause of aortic stenosis in older people.

• Dilated cardiomyopathy.

• Hypertrophic cardiomyopathy.

• Some heart problems present from birth (congenital). It is then usually part of a complex heart deformity.

• Infection of the valve (infective endocarditis).

• A leaky heart valve may occasionally occur following heart valve surgery.

• A complication of various uncommon diseases.

What are the possible complications?

Various complications may develop, depending on the valve affected and the severity of the problem.

The main possible complications that may develop include the following:

• Atrial fibrillation develops in about 4 in 10 cases. In this condition, the heart beats in a fast and irregular way. This occurs because the electrical signals in the enlarged atrium become faulty. The irregular heart rhythm can cause the sensation of a 'thumping heart' (palpitations) and make you even more breathless. See the separate leaflet called Atrial Fibrillation.

• Heart failure may develop and gradually become more severe. This causes worsening shortness of breath, tiredness, and fluid retention in various tissues of the body. See the separate leaflet called Congestive Heart Failure.

• Stroke. A blood clot may form within the enlarged left atrium, which does not fully empty into the ventricle with each heartbeat. A blood clot is more likely to occur if you also develop atrial fibrillation. A blood clot may travel through the heart, be carried in the bloodstream and get stuck and block a blood vessel in another part of the body. For example, it may get stuck in a blood vessel going to the brain and cause a stroke. See the separate leaflet called Stroke.

• Endocarditis sometimes develops. This is an infection of the valve. (Damaged valves are more prone than normal valves are to infection.) Unless promptly treated, endocarditis can cause serious illness. See the separate leaflet called Infective Endocarditis.

How are heart valve problems diagnosed?

• A doctor may hear a heart murmur or other abnormal noises when listening with a stethoscope. Murmurs and noises are due to blood passing through abnormal heart valves, or to abnormal movement of valves. There are typical murmurs and noises which occur with each heart valve problem.

• Initial tests usually include a chest X-ray and a heart tracing (an electrocardiogram, or ECG).

• An ultrasound scan of the heart (an echocardiogram, or 'echo') can confirm the diagnosis.

• Other heart tests, including computerised tomography (CT) scans and magnetic resonance imaging (MRI) scans can help to assess the severity of the condition.

• Cardiac catheterisation may be done to assess the severity of the heart valve problem. In this test a thin tube called a catheter is inserted into either the main blood vessel in the top of the leg (femoral artery) or an artery in the wrist (radial artery). It is passed up to the heart. A small device on the tip of the catheter can measure the pressure on either side of the heart valve.

What is the treatment for heart valve disease?

Any treatment will depend on which valve is affected and the severity of the heart valve problem. Learn more about the treatments for mitral stenosis, mitral regurgitation, aortic stenosis and aortic regurgitation.

Medication

Mild cases may not require any regular medication. Some medicines may be prescribed to help ease symptoms, or to help prevent complications. For example:

• Angiotensin-converting enzyme (ACE) inhibitors are medicines which help to reduce the amount of work the heart does. One may be prescribed to ease symptoms of heart failure.

• 'Water' tablets (diuretics) usually help if you are breathless. They make the kidneys produce more urine. This gets rid of excess blood and fluid which may build up in the lungs or other parts of the body with the back pressure from the heart.

• If you develop atrial fibrillation, several medicines can be used to slow the heart rate down. They include beta-blockers, calcium-channel blockers and digoxin. Shocking the heart with an electrical current (a procedure called cardioversion) is also an option in some people who develop atrial fibrillation as a complication.

• Anticoagulation medication is usually advised if you develop atrial fibrillation. This helps to prevent blood clots from forming.

Surgery

Surgery to stretch, repair or replace the heart valve may be needed in some cases. Surgical treatment has greatly improved the outlook for many cases of severe valve disease. Surgery has a very good success rate.