Risk factors

Coarctation of the aorta often occurs along with other congenital heart defects. Certain heart conditions are often associated with coarctation, including:

• Bicuspid aortic valve. The aortic valve separates the lower left chamber (left ventricle) of the heart from the aorta. A bicuspid aortic valve has two flaps (cusps) instead of the usual three. Many people with coarctation of the aorta have a bicuspid aortic valve.
• Sub-aortic stenosis. Sub-aortic stenosis occurs when there is a narrowing of the area below the aortic valve that obstructs blood flow from the left ventricle to the aorta. This narrowing may be in the form of a fibrous membrane.
• Patent ductus arteriosus. The ductus arteriosus is a blood vessel that connects a baby's left pulmonary artery to the aorta. It allows blood to bypass the lungs while the baby is growing in the womb. Shortly after birth, the ductus arteriosus usually closes. If it remains open, it's called a patent ductus arteriosus.
• Holes in the wall between the left and right sides of the heart. Some people are born with a hole in the wall (septum) between the upper heart chambers (atrial septal defect) or the lower heart chambers (ventricular septal defect).This causes oxygen-rich blood from the left side of the heart to mix with oxygen-poor blood in the right side of the heart.
• Congenital mitral valve stenosis. The mitral valve is between the upper and lower left heart chambers. It lets blood flow through the left side of your heart. In mitral valve stenosis, the valve is narrowed. As a result, the movement of blood between the upper and lower left heart chambers is reduced, increasing the pressure in the upper left chamber (atrium). The oxygen-rich blood from the lungs returns to the heart through veins that attach to the upper left chamber. Increased pressure in the left atrium may result in symptoms of lung congestion. These symptoms include shortness of breath, difficulty breathing during exercise and shortness of breath when lying flat.

Coarctation of the aorta is more common in males than in females, as well as in those who have certain genetic conditions, such as Turner syndrome.