Aortic Dissection

The aorta is the main vessel that carries blood from your heart to the rest of your body, and it is made up of 3 layers. An aortic dissection is a tear in the wall of the aorta that occurs between the inner and middle of those 3 layers. As the tear extends along the wall of the aorta, it can cause blood to flow in between the layers of the aorta and “dissect” the layers apart, thus the name. An aortic dissection can reduce the blood flow to your brain, arms, kidneys, liver, bowels, spinal cord, and legs, depending on how it impacts the flow of blood to the branches of the aorta. The dissection can also cause the aorta to rupture, which may lead to life-threatening bleeding. An aortic dissection is a serious medical condition that occurs in about 2 out of every 10,000 people. It can develop in anyone but most often is seen in men between the ages of 40 and 70.

When the aorta leaves the heart, it first moves up through the chest toward the head; this section is called the ascending aorta. It then bends (arches) and moves down through the chest and abdomen; this section is called the descending aorta. Acute (sudden) dissection involving the ascending aorta is typically considered a surgical emergency and generally must be treated with an open operation involving removal of the dissected aorta and replacement with an artificial material. Dissection involving only the descending thoracic aorta may be treated with minimally invasive procedures such as stenting (called thoracic endovascular aortic repair, or TEVAR), open surgery, or with drugs to lower blood pressure. The choice of therapy depends on whether the dissection causes problems with flow to the branch vessels that arise from the aorta, or if there is an aneurysm associated with the dissection.

Oftentimes a delayed procedure is needed in patients due to an aneurysm that may develop over time, so strict follow-up is needed after discharge from the hospital. This is also true for patients with ascending aortic dissection that extends into the descending thoracic aorta, because of a similar risk of aneurysm over time.

The cause of aortic dissection usually involves multiple factors. Some common risks include:

• Smoking
• Uncontrolled hypertension (high blood pressure)
• Advanced age
• Hypercholesterolemia
• Bicuspid aortic valve
• Cocaine or methamphetamine use
• Narrowing (coarctation) of the aorta
• Connective tissue disorders, such as Marfan, Loeys-Dietz, or Ehlers-Danlos syndromes, among other rare genetic disorders
• Complications from open heart surgery or endovascular procedures
• Hypertension associated with pregnancy
• Aneurysm associated with conditions such as arteritis and syphilis