Aortic Dissection
Overview
Aortic dissection is a life-threatening heart condition where the inside lining of the main artery (aorta) carries blood away from the heart and tears. If the tear in the lining isn’t treated before the aorta ruptures, the survival rate is 1 in 2 cases.1
The aorta
The aorta is the main artery that carries blood from the heart to the rest of your body. The aorta is exposed to the highest blood pressure in the body. Like all arteries, the aorta has a smooth layer on the inside, a thick layer of muscle in the middle, and a rough layer on the outside. Rarely, this inner lining can tear, and blood will flow between the artery wall's layers, pushing the layers apart. This means the blood flow pressure can rupture the aorta, causing serious internal bleeding. It also means that blood is no longer flowing adequately to the body’s organs and tissues, usually supplied by the aorta.
Risk factors for aortic dissection
Aortic dissection can happen to anyone, but men 40–70 years old are at the greatest risk.1 The following conditions, among others, can increase the risk of aortic dissection:
- Existing aortic aneurysm – An aneurysm is a weakened or bulging area in an artery that can rupture. A preexisting aneurysm is a risk factor for aortic dissection, and aortic dissection can also cause an aneurysm to form.
- High blood pressure – Hypertension, or high blood pressure, can progressively damage the wall of the aorta, weakening it and making it more likely to tear.
- Atherosclerosis – Atherosclerosis, or “hardening of the arteries,” is when a fatty, waxy substance called plaque builds up in the artery wall. This same disease process is behind heart attacks and the majority of strokes. Plaques forming in the aorta's wall can weaken the artery wall, making it more susceptible to tearing.
- Trauma to the chest – Blunt trauma, such as a car accident, can cause aortic dissection.
- Coarctation of the aorta – This is a congenital (present at birth) heart defect in which a portion of the aorta is narrowed. In some cases, depending on how the heart defect was treated, there can be a weakened aorta wall that increases the risk of having an aorta aneurysm or dissection.
- Bicuspid aortic valve – A valve between your heart and the aorta regulates blood flow. Normally, this valve has three flaps (leaflets) that open and close to control blood flow. However, someone born with a bicuspid valve only has two leaflets. Over time, this valve can leak or stiffen. Some medical researchers think the bicuspid valve is part of a larger connective tissue disorder (the tissues that hold the body together) that affects the walls of the aorta, leaving the aorta more susceptible to weakening, bulging, tearing, and rupturing.
- Marfan syndrome, Ehlers-Danlos syndrome, Loeys-Dietz syndrome, and other connective tissue disorders – These syndromes affect the connective tissues of the body, which hold the body together. These connective tissue disorders can lead to an enlarged aorta or separation of the layers of the aorta’s wall. This makes the aorta more likely to burst or tear.
- Pregnancy – Very rarely, an individual may experience aortic dissection during pregnancy. Typically, the patient will have one or more of the risk factors above that have gone undiagnosed until the additional cardiovascular stressors of pregnancy reveal them.