An aortic dissection is a tear in the inner lining of the aorta (the main artery that carries oxygen-rich blood from the heart to the rest of the body), creating a space between the inner and outer layers. If blood leaks into that space, then a variety of potentially fatal conditions could result, including heart attack or stroke.

There are two types of aortic dissections: acute and chronic. Acute aortic dissections involve sudden, severe symptoms and usually requires emergency open-heart surgery. An aortic dissection is classified as chronic if it has been present for at least two weeks, usually without recognizable symptoms. This also usually requires emergency treatment.  

Although aortic dissection remains relatively rare, a number of conditions and diseases may put people at higher risk. The leading risk factors are age and high blood pressure, which occur in more than 70 percent of people who suffer from an aortic dissection. Atherosclerosis (hardening of the arteries) as well as a history of heart disease or aortic disease, also raise the risk of aortic dissection.