Before reading this section you should make sure you know the basic structure,
nomenclature and function of the four heart
valves. Click
here to see the valves in action during the cardiac cycle (requires flash).
Stenosis Aortic stenosis is the most common of all heart valve disorders. The narrowing of the aortic valve limits the cardiac output and forces the left ventricle to work harder, causing it to become abnormally large.
Drugs such as cardiac glycosides can be used to control the heart failure caused by aortic stenosis but severe cases may require heart valve replacement or balloon valvuloplasty.
InsufficiencyAortic insufficiency also places considerable strain on the left ventricle, causing it to thicken and enlarge. The insufficient valve allows blood to regurgitate back from the aorta into the ventricle, forcing the ventricle to "repump" the same blood again. The regurgitation reduces the efficiency of the heart considerably and extreme cases can lead to heart failure. Initial symptoms include breathlessness and the inability to perform strenuous exercise.
