An aortic dissection is a serious condition in which the inner layer of the aorta, the large blood vessel branching off the heart, tears. Blood surges through the tear, causing the inner and middle layers of the aorta to separate (dissect). If the blood-filled channel ruptures through the outside aortic wall, aortic dissection is often fatal.
Aortic dissection is relatively uncommon. The condition most frequently occurs in men in their 60s and 70s. Symptoms of aortic dissection may mimic those of other diseases, often leading to delays in diagnosis. However, when an aortic dissection is detected early and treated promptly, the chance of survival greatly improves.
Aortic dissection symptoms may be similar to those of other heart problems, such as a heart attack. Typical signs and symptoms include:
- Sudden severe chest or upper back pain, often described as a tearing, ripping or shearing sensation, that radiates to the neck or down the back
- Sudden severe abdominal pain
- Loss of consciousness
- Shortness of breath
- Sudden difficulty speaking, loss of vision, weakness or paralysis of one side of your body, similar to those of a stroke
- Weak pulse in one arm or thigh compared with the other
- Leg pain
- Difficulty walking
- Leg paralysis
An aortic dissection occurs in a weakened area of the aortic wall. Chronic high blood pressure may stress the aortic tissue, making it more susceptible to tearing. You can also be born with a condition associated with a weakened and enlarged aorta, such as Marfan syndrome, bicuspid aortic valve or other rarer conditions associated with weakening of the walls of the blood vessels. Rarely, aortic dissections are caused by traumatic injury to the chest area, such as during motor vehicle accidents.
Aortic dissections are divided into two groups, depending on which part of the aorta is affected:
- Type A. This more common and dangerous type involves a tear in the part of the aorta where it exits the heart or a tear in the upper aorta (ascending aorta), which may extend into the abdomen.
- Type B. This involves a tear in the lower aorta only (descending aorta), which may also extend into the abdomen.
Risk factors for aortic dissection include:
- Uncontrolled high blood pressure (hypertension)
- Hardening of the arteries (atherosclerosis)
- Weakened and bulging artery (pre-existing aortic aneurysm)
- An aortic valve defect (bicuspid aortic valve)
- A narrowing of the aorta at birth (aortic coarctation)
Certain genetic diseases increase the risk of having an aortic dissection, including:
- Turner's syndrome. High blood pressure, heart problems and a number of other health conditions may result from this disorder.
- Marfan syndrome. This is a condition in which connective tissue, which supports various structures in the body, is weak. People with this disorder often have a family history of aneurysms of the aorta and other blood vessels or family history of aortic dissections.
- Other connective tissue disorders. This includes Ehlers-Danlos syndrome, a group of connective tissue disorders characterized by skin that bruises or tears easily, loose joints and fragile blood vessels and Loeys-Dietz syndrome, with twisted arteries, especially in the neck.
- Inflammatory or infectious conditions. These may include giant cell arteritis, which is an inflammation of the arteries, and syphilis, a sexually transmitted infection.
Other potential risk factors include:
- Sex. Men have about double the incidence of aortic dissection.
- Age. The incidence of aortic dissection peaks in the 60s and 80s.
- Cocaine use. This drug may be a risk factor for aortic dissection because it temporarily raises blood pressure.
- Pregnancy. Infrequently, aortic dissections occur in otherwise healthy women during pregnancy.
- High-intensity weightlifting. This and other strenuous resistance training may increase the risk of aortic dissection by increasing blood pressure during the activity.
An aortic dissection can lead to:
- Death due to severe internal bleeding
- Organ damage, such as kidney failure or life-threatening intestinal damage
- Stroke
- Aortic valve damage (aortic regurgitation) or rupture into the lining around the heart (cardiac tamponade)