Aorta dissection is a tear in the inner layer of a weakened area of your aorta. Your aorta is the main artery that delivers oxygen- and nutrient-rich blood from your heart to the rest of your body. Aortic dissection is a life-threatening condition that requires immediate recognition. Treatment includes several types of surgery and medication.
Your aorta is the main artery that carries oxygen-rich blood away from your heart to the rest of your body. The wall of your aorta is made up of three tissue layers — an inner layer (intima), middle layer (media) and outer layer (adventitia).
An aortic dissection begins abruptly when a tear occurs in the inner layer of a weakened area of your aorta. Blood surges through the tear, causing the inner and middle layers to separate (“dissect”). As diverted blood flows between the tissue layers, the normal blood flow to parts of your body may be slowed or stopped, or the aorta may rupture completely.
Aortic dissection is a life-threatening condition that can cause sudden death if it is not recognized and quickly treated.
Aortic dissection is a separation between the inner and middle layers of the aortic artery wall. Blood pours through a tear in the inner layer, causing a bulge and weakness in that area of the aortic artery.
The aorta runs throughout your torso. It begins at the main pumping chamber of your heart (the left ventricle), extends up through the front middle of your chest, arches from front to back under the base of your neck, then travels downward along the front of your spine — through your chest (thoracic aorta) and abdomen (abdominal aorta) — before branching just below your navel to two other arteries called the right and left common iliac arteries.
There are two main types:
Another classification system (DeBakey Classification) defines dissection by three types. Type 1 originates in the ascending aorta and extends through the downstream aorta. Type 2 originates and is limited to the ascending aorta (both would be considered Stanford Type A). Type 3 originates in the descending aorta and extends downward (similar to Type B).
An aortic aneurysm is a bulge — like a bubble or a balloon — in a weakened area of the wall of the aorta or across an entire segment of the aorta. Aortic aneurysm can lead to aortic rupture and aortic dissection.
An aortic rupture is a complete tear through all three layers of the aorta — like a rip or a hole — in the wall of the aorta. Blood bursts through the hole into the surrounding body cavity.
An aortic dissection is a tear in the inner aortic layer that allows blood to enter and further separate the inner and middle layers of the wall of the aorta and typically extends over a long length of the aorta in either direction and may extend into branch vessels originating from the aorta.
The most common characteristic of aortic dissection is its abrupt start. It can happen at any time, while doing anything, or at rest or when you’re sleeping.
Common signs and symptoms include:
Aortic dissection is life-threatening. About 40% of patients die immediately from complete rupture and bleeding out from the aorta. The risk of dying can be as high as 1% to 3% per hour until the patient gets treatment. If you have symptoms of aortic dissection, severe chest pain, or symptoms of a stroke, call 911 or seek emergency care. When the diagnosis is made, you may be transferred by a critical care transport team to a referral center with the expertise to manage these complex conditions.
Aortic dissection happens because there is an underlying, slow breakdown of the cells that make up the walls of your aorta. The breakdown has likely been going on silently for many years before the weakened area of the aortic wall finally gives way, resulting in a tear, which leads to the aortic dissection.
Why does the aortic wall weaken in some people and not others? It’s believed that most aortic dissections are caused by an underlying vulnerability that may be inherited. In others, the stress to the aortic wall from constant high blood pressure can weaken the aorta wall in susceptible people, resulting in a tear and dissection.
Aortic dissection in the ascending aorta (the section closest to the heart where the pressure is the highest) is nearly two times more common than those that occur in the descending aorta. Tears in the aorta typically occur in areas where the stress on the wall of the aorta is highest.
Factors that can increase your risk for developing aortic dissection include:
Aortic dissection can lead to:
Aortic dissection must be diagnosed quickly, in case immediate surgery is needed. The healthcare team needs to determine if you have aortic dissection or other health conditions, such as heart attack and stroke, which produce similar symptoms. Tests that may be ordered include:
Treatment of aortic dissection depends upon the location of the tear and dissection. Immediate surgery is needed for Type A aortic dissection (i.e., when it involves the first part of the aorta close to the heart). Type B aortic dissection requires emergency surgery if the dissection cuts off blood flow to your vital organs including your kidneys, intestines, legs or even your spinal cord. Urgent surgery is needed if there are certain high-risk features noted on CT scan imaging. Less severe cases may be treated with medication initially, delaying surgery until complications develop.
Surgical options include:
Medications, such as beta blockers, may be prescribed to lower heart rate and blood pressure. In some Type B aortic dissection cases, medication alone may be used to treat the dissection initially. Surgery may be able to be delayed for months to years depending on the severity of the tear and extent of dissection.
Many of the factors that increase the risk of developing aortic dissection can’t be changed, such as being born with certain heart conditions, connective tissue disorders, or genetic triggers associated with having a family history of aortic dissection. However, like many other medical diseases and conditions, you can decrease some of your risks by changing the risk factors that can be modified. These risks include:
It’s important for first-degree relatives of a person who has had an aortic dissection to be screened for their risk of aortic disease. They can be closely followed and treated before an aortic event occurs.
Aortic dissection can be a life-threatening event. People who have acute aortic dissection (sudden onset, Type A) have a high death rate. On average, 15% to 30% of people die after reaching the emergency room even after surgery. People who survive the acute phase are usually left with a chronic dissection remaining in the untreated portions of their aorta that may require later treatment. With modern advances in care, the prognosis in the chronic phase is improving, but life expectancy for people with aortic dissection is shortened compared to the general population.
Every person who survives aortic dissection — even if they didn’t have surgery — needs to be seen at regular intervals (usually every three to 12 months) for follow-up imaging. Imaging allows changes to be caught that can then be acted upon in a safe and timely manner.
Blood pressure medicine, usually beta-blockers, will be prescribed to control your blood pressure and heart rate. You’ll need to take them for the rest of your life. Sometimes more than one blood pressure medication may be needed. If you can’t tolerate these medications, other blood pressure drugs can be used.
Aerobic exercises — such as walking, biking and swimming — may be encouraged. But you’ll need to avoid activities, such as heavy weight lifting (e.g., > half your body weight), which can increase blood pressure and put added stress on your aorta.
A note from Cleveland Clinic
Acute aortic dissection is a medical emergency. If you have symptoms of aortic dissection, call 911. You may need immediate surgery to repair a segment of your aorta. If your dissection is not severe or immediately life-threatening, you may not need surgery right away but will likely need close monitoring in a hospital setting and will likely need surgery at a later time.
If you’ve been diagnosed with aortic dissection, you’ll need to keep your blood pressure under control and will need repeat imaging with CT or MRI to monitor the condition of your aorta. Take your medications and follow all instructions given to you by your healthcare provider. Be sure to keep all your follow-up appointments. It’s critical that your condition is checked for changes on a regularly scheduled basis as determined by your aorta specialist (i.e., cardiologist, vascular surgeon, and/or cardiac surgeon).
Last reviewed by a Cleveland Clinic medical professional on 07/26/2021.
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