The aorta is the large artery that originates in the left ventricle (lower chamber) of the heart. Aortic stenosis is the narrowing or obstruction of the heart’s aortic valve, which prevents it from opening properly and blocks the flow of blood from the left ventricle to the aorta.
As the aortic valve narrows, the pressure increases inside the left heart ventricle. This causes the left heart ventricle to become thicker, which decreases blood flow and can lead to chest pain. As the pressure continues to increase, blood may back up into the lungs. Severe forms of aortic stenosis prevent enough blood from reaching the brain and rest of the body. Lightheadedness and fainting can result.
Aortic stenosis may be present from birth (congenital), or it may develop later in life. It is caused by many disorders. One common cause is rheumatic fever, a complication of untreated strep throat. Calcification of the valve can also cause this condition. In this case, the condition is usually not seen until a person reaches their 70s.
Aortic stenosis occurs in approximately five out of every 10,000 people and is more common among men.