The aorta is the artery that carries oxygen-rich blood away from the heart and on to other arteries that distribute it throughout the body. Aortic dissection is a split the begins in the inner lining of the artery wall. Pumping blood is forced through this opening, where it builds up in the vessel wall and eventually can rupture the outer lining of the artery.
The tear can expand in length back toward the heart (proximal aortic dissection) or, more often, away from the heart (distal aortic dissection). Aortic dissection is most often associated with long-term high blood pressure, but other factors can increase risk, including aortic aneurysm, congenital (present from birth) aortic valve conditions and narrowing (coarctation) or expansion (dilation) of the vessel. Common symptoms of acute (sudden onset) aortic dissection may include abrupt, severe or “tearing” chest pain, sometimes accompanied by cold perspiration.