Doctors aren't certain what causes coarctation of the aorta, or aortic coarctation. For unknown reasons, mild to severe narrowing develops in part of the aorta. Although aortic coarctation can occur anywhere along the aorta, the coarctation is most often located near a blood vessel called the ductus arteriosus. The condition generally begins before birth (congenital).

Rarely, coarctation of the aorta develops later in life. Traumatic injury might lead to coarctation of the aorta. Rarely, severe hardening of the arteries (atherosclerosis) or a condition causing inflamed arteries (Takayasu's arteritis) can narrow the aorta, leading to aortic coarctation.

Coarctation of the aorta usually occurs beyond the blood vessels that branch off to your upper body and before the blood vessels that lead to your lower body. This can often lead to high blood pressure in your arms but low blood pressure in your legs and ankles.

With coarctation of the aorta, the lower left heart chamber (left ventricle) of your heart works harder to pump blood through the narrowed aorta, and blood pressure can increase in the left ventricle. This may cause the wall of the left ventricle to thicken (hypertrophy).

Sept. 15, 2015