What is heart valve disease? 

The heart has two halves, a left and a right, each with two chambers -  the atria and the ventricles. Between the chambers are the heart valves which ensure the blood runs only in one direction, and prevents the heart from pumping blood backwards.

There are also heart valves situated between the ventricles and the major arteries - the aorta and pulmonary artery - where they have the same function. 

Failure in  a valve in the left side  of the heart -  the aortic or the mitral valve - results  in left-sided heart failure. This leads  to an accumulation of fluids in  the lungs, or pulmonary oedema. 

Valve diseases of  the right side of  the heart - the pulmonary and tricuspid valve - are rare but can occur as  the result  of some forms of congenital  heart disease  or long-term left-sided  heart failure.

Right-sided heart failure is characterised by fluid accumulation in the body, particularly in the legs, abdominal cavity and the liver. 

Malformation of  the heart valves can be divided into two categories: narrowed (stenosed) valves and leaking (regurgitant)  valves - or a combination  of both. 

What causes heart valve disease? 

Narrowed valves (Aortic Stenosis, Mitral Stenosis)

These may be due to: 

• congenital abnormality 
• degeneration through atherosclerosis (aortic stenosis only) 
• damage from rheumatic fever 
• excessive calcification  in old age (aortic stenosis only). 

Leaking valves (Aortic Regurgitation, Mitral Regurgitation, Tricuspid Regurgitation)

These may be due to: 

• bacterial infection or inflammation of  a valve 
• excessive floppiness of  the leaflets (mitral valve prolapse) 
• enlargement of  the heart or aorta - the main blood vessel into which the left ventricle pumps. 

What does a malformation of the heart valve feel like? 

In mild cases, there are no symptoms and generally no cause for worry, although antibiotic treatment  to prevent  the risk of a valve infection is recommended, for example to cover a dental procedure when there is a chance that there will be some bacteria introduced  into the bloodstream temporarily. 

• Serious cases may not be evident for a long time either. There may be no symptoms, even though the heart is already under strain. In cases of stenosis of the aortic valve, it is important  to be aware of the following possible symptoms, since this condition may result in sudden death: 
• dizziness or a faint brought on by physical effort 
• shortness of breath 
• angina (chest pain) on exertion. 

How does the doctor make the diagnosis? 

The diagnosis is based on the patient's case history, examining the  heart and by using a stethoscope to listen for any abnormal sounds or murmurs coming from the heart valves or heart muscle. 

To find out if  the heart valve abnormality is significant, the doctor can refer the patient to a hospital for further examinations, such as echocardiography  and cardiac catheterization. 

Echocardiography  

This is an ultrasound scan of the heart. It gives an accurate measure of the degree of the leak and/or stenosis, whether the heart's pumping ability is impaired and  can often give the exact cause  of the valve disease. 

The resolution and accuracy of echocardiography is enhanced by performing 'transoesophageal echocardiography' in these patients. This involves the patient swallowing  a fibre-optic tube under sedation. Much clearer pictures may be obtained from behind the heart with this technique. 

Cardiac catheterization 

The pressure in  the atria, the ventricles and the great vessels - the aorta and pulmonary artery -  is measured using catheters. Through injecting a dye which  is visible on an X-ray, the doctor can also assess the degree of the leakage. 

What  can the doctor do? 

The doctor can try to find the cause of the valve malformation,  or refer  the patient to  the hospital for further investigation  and possible treatment. 

Which medications are used? 

For prevention of infection 

An abnormal valve is more likely to become infected with bacteria. This could occur, for example, if bacteria enters the bloodstream during surgical procedures, sin or other types of medical infections.  

For treatment of symptoms 

Diuretics help the body to excrete excessive salts and fluid through the kidneys: 

• loop diuretics, which  have a strong effect, are the main type used 
• potassium-sparing diuretics  may be given to complement  the loop diuretic 
• a thiazide-diuretic  may be used as  an additional diuretic if heart-failure symptoms are severe. 

Medicines to improve a poor heart function such as ACE inhibitors or angiotensin-II receptor blocking agents (ARBs), help the heart work more effectively in the presence of a leaky valve. 

Warfarin may be used as an anticoagulant o 'thin'  the blood if there is an increased risk of blood clot development to reduce the risk of stroke.  Nitrate-preparations and other vasodilators  are used to relax  and dilate the arteries. These are used if the patient cannot tolerate ACE inhibitors or ARBs. 

Further development and treatment possibilities 

A serious untreated heart valve abnormality may eventually lead to  symptoms including congestive heart failure, angina, cardiac arrhythmias, syncope (loss of consciousness), or sudden cardiac death.  Significant valve defects can be treated surgically either by replacement with an artificial valve or by repairing the affected valve (usually specific to the mitral valve). 

Following an operation of this type, it is usually necessary to take anti-clotting medication such as warfarin - sometimes permanently, depending on the type of surgery performed and the type of valve replacement. 

If the patient is unsuitable for surgery, because of another coexisting illness or irreversible, end-stage heart failure, then medications can be used for the treatment of heart failure symptoms.