The majority of people who have
aortic valve stenosis are older than 65 and have
developed the condition slowly, over many years.
Most young people and teens who have the condition developed it as a
result of a defect at birth (congenital heart defect). The most common heart
defect that causes aortic stenosis is a
bicuspid
aortic valve
. This is the most common cause of aortic stenosis in people
younger than 65. A normal (tricuspid) aortic valve has three flaps called
leaflets; a bicuspid valve only has two leaflets.
Males are 4 times more likely than females to have aortic
stenosis.1
Some people may develop aortic stenosis after having
rheumatic fever as a child. It usually takes 30 to 40
years after a case of rheumatic fever for aortic stenosis to develop. Rheumatic
fever has been rare in Canada and the United States since the 1970s.