The heart has four valves:

1. Mitral valve – allows blood flow from the left atrium to the left ventricle
2. Aortic valve – allows blood to flow from the left ventricle to the aorta to be circulated to the rest of the body
3. Tricuspid valve – allows blood flow between the right atrium and the right ventricle
4. Pulmonary valve – allows blood to flow from the right ventricule to the pulmonary artery to the lungs for reoxygenation

Valvular disease occurs when the valves don’t open or close correctly causing regurgitation, stenosis or atresia. Regurgitation occurs when the valve leaflets don’t close properly, resulting in blood leaking back. This causes the heart to work harder which may lead to heart failure. Stenosis is when the valve leaflets don’t open properly due to stiffness or thickness, which reduces the amount of blood flow going through the valve. This also causes the heart to work harder. Atresia or congenital defects occurs when the valve hasn’t formed correctly, such as a bicuspid aortic valve. This usually results in regurgitation, stenosis or both. Valvular disease (heart murmurs) are assessed with echocardiograms. Symptoms can also include shortness of breath, lethargy, palpitations. Frequently, those with mild or even moderate amount of valvular disease experience no symptoms and are completely unaware of it. Valvular disease can be congenital, age related or in response to a heart attack.

For more information on valve disease.
Heart valve disease | Heart Foundation