Stenosis

When valves don't open completely, the condition is known as stenosis.

When a valve is stenotic, blood has to flow through a smaller opening than normal forcing the chamber behind the valve to pump blood more forcefully than usual. Stenosis results from progressive hardening or stiffening of valve leaflets from calcium deposits or scarring. This causes abnormal stress and strain on the heart muscle, which can become irreversibly weakened.

Aortic Stenosis

Mitral Stenosis

Regurgitation

When valves don't close completely, the condition is known as regurgitation or insufficiency.

The valves, themselves, or supporting structures below, may be loose, torn or distorted, allowing a gap to develop between the valve leaflets. If the valve doesn't close completely, blood leaks backward into the cardiac chamber at the same time it is receiving blood from the preceding chamber. This results in over-stretching of the heart muscle, which, if sufficiently severe and prolonged, can permanently damage the heart muscle.

Aortic Regurgitation

Mitral Regurgitation

Causes Valvular heart diseases are caused by:

• hereditary (genetic) factors
  • congenital/structural heart malformations
    
    
  • abnormalities of the inner working of heart muscle cells in structurally normal hearts
    
    
• rheumatic fever
  
  
• bacterial infections such as infective endocarditis
  
  
• changes resulting from the aging process