What is valvular heart disease?

Your heart is a muscle which pumps blood around your lungs and the rest of your body. There are four valves in your heart. These valves guard the entrances and exits of the two pumping chambers in your heart (the right and left ventricles). The job of a valve is to make sure that fluid flows only in the correct direction. The valves at the entrances to the pumping chambers are there to make sure that the blood only goes in. The valves at the exits only let blood out.

A diseased or damaged valve can affect the flow of blood in two ways:

If the valve does not open fully, it will obstruct the flow of blood. This is called valve stenosis. If the valve does not close properly, it will allow blood to leak backwards. This is called valve incompetence or regurgitation. Both stenosis and incompetence put an extra strain on the heart. If you have stenosis, the valve will obstruct the flow of blood, so your heart will have to pump harder to force the blood past the obstruction. If you have incompetence, your heart has to do extra work to pump the necessary volume of blood forwards against the blood flowing backwards through the leaking valve.