1-29

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1-29. VALVE DISORDERS

a. The function of the heart's valves is to maintain the forward flow of blood from the atria to the ventricles and from the ventricles into the great vessels.

b. Valvular damage interferes with this forward flow by stenosis (narrowing) of the valve or by impaired closure of the valve that allows a backward leakage of blood. This is called valvular insufficiency or regurgitation.

c. If the heart muscle itself remains strong, the circulatory mechanisms can adjust and compensate for a bad valve. These modifications are called compensatory changes.

d. Valve deficiencies cause two basic types of stress on the heart. If the stress produced is greater than the heart's ability to compensate, eventual deterioration will occur. The two types of heart stress associated with valve deficiencies are:

(1) Pressure overload (associated with valvular stenosis).

 

(2) Volume overload (associated with valvular insufficiency and regurgitation).

 

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