Which patient demographic is more likely to have a congenital cause of aortic stenosis?

Patients under 70 years old are more likely to have a congenital cause of aortic stenosis, primarily because the congenital form of this condition is often related to developmental issues in the heart that present early in life. Most commonly, congenital aortic stenosis is due to a bicuspid aortic valve, where the valve has only two cusps instead of the normal three. This condition can lead to early stenosis as the patient ages.

In contrast, patients over 70 years old generally have aortic stenosis that stems from age-related degeneration and calcification of the aortic valve rather than a congenital issue. Similarly, a history of rheumatic fever typically leads to aortic stenosis through the scarring of the valve rather than congenital malformation. Patients with coronary artery disease are often dealing with systemic atherosclerosis or ischemic heart disease, which are also age-related and not fundamentally linked to congenital conditions. Thus, the link between age and the type of aortic stenosis is crucial to understanding why younger patients more commonly exhibit congenital causes.