Dissection of the Aorta

What Is a Dissection of the Aorta?

The aorta is a large artery that carries blood out of your heart. If you have a dissection of the aorta, it means that blood has entered the wall of the artery that’s between the inner and middle layers. This can happen if the inner layer of your aorta tears, allowing blood to pass from the main body of the artery into the wall.

Sometimes, blood hemorrhages from the tiny vessels that supply the outside wall of your aorta. This can also lead to blood accumulating inside the layers of the aortic wall.

The danger is that the dissection could channel blood out of your aorta, causing a fatal rupture of the artery. Serious complications can arise if the dissection sends blood into the space around your heart or lungs. Call 911 immediately if you have severe chest pain or other symptoms of an aortic dissection.

Symptoms

Symptoms of a Dissection of the Aorta

The symptoms of an aortic dissection can be difficult to distinguish from those of other heart conditions, such as a heart attack.

Chest pain and pain in the upper back are the most common symptoms of this condition. There’s typically severe pain, coupled with a feeling that something is tearing in your chest. Unlike in the case of a heart attack, the pain usually begins suddenly and seems to move around.

Some people have milder pain, which is sometimes mistaken for muscle strain, but this is less common.

Other signs and symptoms include:

• breathlessness
• fainting
• sweating
• weakness or paralysis on one side of the body
• trouble speaking
• a weaker pulse in one arm than in the other
• dizziness or confusion

Causes

Causes of Dissection of the Aorta

Although the exact cause of aortic dissections is unknown, doctors believe that high blood pressure is a contributing factor because it causes strain on the walls of your arteries.

Anything that weakens your aortic wall can cause a dissection. This includes inherited conditions in which your body tissues develop abnormally, such as Marfan syndrome, and accidental injuries to the chest.

Types of Dissection of the Aorta

The aorta travels upward when it first leaves your heart. This is called the ascending aorta. It then arches downward, passing from your chest into your abdomen. This is known as the descending aorta. A dissection can occur in the ascending or descending part of your aorta. Aortic dissections are classified as type A or type B:

Type A

Most dissections are found in the ascending section, where they’re classified as type A.

Type B

Dissections in the descending aorta are classified as type B. They tend to be less life-threatening than type A and require less urgent treatment.

Risk Factors

Who Is at Risk for a Dissection of the Aorta?

Your risk of an aortic dissection increases with age and is especially high if you’re a male between 40 and 70 years old.

The following factors can also increase your risk:

• high blood pressure
• smoking
• atherosclerosis, or hardening of your arteries
• conditions such as Marfan syndrome, in which your body’s tissues are weaker than normal
• surgical procedures done near the heart
• motor vehicle accidents involving chest injuries
• a narrowed aorta
• an aorta with a faulty valve
• cocaine use, which can cause abnormalities in your circulation
• pregnancy

Diagnosis

How Is a Dissection of the Aorta Diagnosed?

Your doctor will examine you and use a stethoscope to listen for abnormal noises coming from your aorta. When your blood pressure is taken, the reading may be different in one arm than in the other.

A test called an electrocardiogram (EKG) may be needed to see if you’re having a heart attack. Sometimes an aortic dissection can be mistaken for a heart attack, and sometimes you can have both conditions at the same time.

You may also need to have imaging scans done. These can include:

• a chest X-ray
• a CT scan
• an MRI scan
• an echocardiogram

An echocardiogram involves passing a device that emits sound waves down your throat until it’s close to the area of your heart. The sound waves are used to create an image of your heart and aorta.

Treating a Dissection of the Aorta

Type B dissection can often be treated with medication. Type A dissection typically requires surgery.

Medications

You’ll receive drugs to relieve your pain. Morphine is often used for pain. You’ll also get medication to lower your blood pressure. Beta-blockers are usually used for this.

Surgeries

The torn section of your aorta is removed and replaced with a synthetic graft. If one of your heart valves has been damaged, this will also be replaced.

You may also need surgery if your type B dissection continues to worsen even when your blood pressure is under control.

Outlook

Long-Term Outlook for People with Dissection of the Aorta

If you have a type A dissection, emergency surgery before the aorta ruptures gives you a good chance of surviving and recovering. Once your aorta has ruptured, your chances of survival are 50 percent. Early detection is essential. A type B dissection is usually manageable in the long term with medication and careful monitoring.

If you have a condition that increases your risk of aortic dissection, such as atherosclerosis, it’s important that your doctor monitors the width of your aorta every year. If your aorta grows beyond a certain width, you may need to have the abnormal section replaced to prevent a dissection.