An aortic dissection results from a tear in the aorta - the main blood vessel in the heart. The aorta originates from the left ventricle of the heart upward. This part is known as the ascending aorta. It then turns left forming an arch, and passes downward, known as the descending aorta. This supplies oxygenated blood to the body. When a dissection occurs in the ascending aorta, it is a Type A dissection. When the dissection is in the descending aorta, it is a Type B dissection.

The aorta is comprised of three layers: the innermost, middle and outermost layers. When a dissection occurs, the innermost layer of the aorta tears, creating a false channel that allows blood to flow into the middle layer. With each heartbeat, the dissection can extend, causing the aortic wall to separate or dissect. The patient is at risk for a complete rupture - causing sudden death as the brain and other vital organs will not get enough blood supply.

Aortic dissection can occur in all age groups; however, it is rare in infants and children less than 16 years of age. Most dissections affect males two to three times as often as females. The peak incidence is when people are in their 60s and 70s.

There are certain factors that may make someone more at risk for acute aortic dissections. These include high blood pressure, Marfan's syndrome, aortic valve problems that are present at birth, autoimmune diseases and traumatic injuries.

Patients that have acute aortic dissections often describe the pain as a sharp, ripping, stabbing or tearing sensation, which may radiate to the back. There can also be neurologic symptoms, heart failure, shortness of breath, fainting, and coughing or vomiting blood, depending on where the dissection is. Physicians will diagnose and treat aortic dissections with blood work, X-rays, echocardiograms and special CT scans.

The goal in managing acute aortic dissection is to prevent further dissection and minimize the damage to organs that may not have received enough blood flow. This is accomplished by a combination of controlling the patient's blood pressure, performing surgery, and possibly special radiological intervention. Typically, Type A dissections require surgical intervention, while Type B dissections can often be managed medically. Often, surgical intervention will require replacement of the aortic valve.

Acute aortic dissection is a medical and often surgical emergency. Good outcomes require prompt diagnosis and immediate treatment. People who survive an acute aortic dissection, either Type A or Type B, will require a lifetime of follow-up.

Sharon Welsh, RN, BSN and CVRN, and Carolyn Bellamah, FNP, are in the cardiac surgery program at the International Heart Institute at St. Patrick Hospital.