What is an aortic dissection?
An aortic dissection is a serious condition in which a tear or split occurs in the inner layer of the aorta. The aorta is the largest blood vessel branching from the heart and supplies blood and oxygen to the entire body. If a tear occurs, blood is able to pass through the opening. This can cause the inner and middle layers of the aorta to separate, or dissect.
The condition is relatively rare, but most common in people between the ages of 50 and 65, tending to affect men more often than women. The main symptom is pain in the chest, upper back or abdomen.
An aortic dissection is a medical emergency requiring immediate treatment. In most cases, surgery will be necessary to repair the blood vessel.
Aortic dissection symptoms
The main symptom of aortic dissection is a sudden, intense pain in the chest and upper back, commonly described as a shearing or ripping sensation. This pain may spread to the back, arms or legs, depending on the location of the dissection.
Other symptoms may include:
- Shortness of breath
- Cold hands or feet
- General weakness
People experiencing an aortic dissection may also lose consciousness, depending on the amount of blood that is lost from the blood vessel. Symptoms may be difficult to distinguish from those of other heart conditions, including heart attack and stroke.
Causes of aortic dissection
An aortic dissection typically occurs in a weakened area of the aorta. According to the Stanford classification system, there are two types of the condition, each defined by which part of the aorta is affected:
- Type A: Tear occurs close to where the aorta exits the heart or in the upper aorta, known as the ascending aorta. May affect the upper aorta only or the upper aorta, as well as the lower aorta. Even if only a very small section of the upper aorta is affected and a large area of the lower aorta, this will still be classed as type A.
- Type B: Tear occurs in the lower aorta, known as the descending aorta.
The DeBakey classification system, on the other hand, identifies three types of aortic dissection:
- Type I: Tear occurs in the ascending and descending aorta.
- Type II: Tear occurs in the ascending aorta only.
- Type III: Tear occurs in the descending aorta only.
The type of aortic dissection being experienced may affect the treatment options available.
Aortic dissection is more common in men than in women, and people between the ages of 50 and 65 are most at risk.
Other risk factors include:
- High blood pressure
- High cholesterol levels
People who already have a weakened or enlarged aorta – an aortic aneurysm – or who have experienced angina, a heart attack or stroke are also at an increased risk of aortic dissection. Less common causes are cocaine use and chest injuries, such as those experienced as a result of a car accident.
Certain genetic conditions are also known to increase the risk of aortic dissection; these include Marfan syndrome, Ehlers-Danlos syndrome and Turner's syndrome.
Diagnosing aortic dissection
The diagnosis is made by a doctor based on the symptoms and appearance of the affected person. In an emergency situation, an ultrasound scan may be carried out immediately to confirm the diagnosis.
Other tests that may help to confirm the diagnosis include:
- Electrocardiogram (ECG)
- X-rays of the chest and abdomen
- CT scan (computed tomography)
- MRI scan (magnetic resonance imaging scan)
A type A, or type I and type II, aortic dissection is a medical emergency requiring surgery to repair the damaged aorta before complications can occur. Typically, a valve-sparing aortic root replacement, also known as a David procedure, will be performed. This procedure preserves the aortic valve, grafting it to a new section of aortic tissue. In cases where the aortic valve is destroyed completely, it will typically be replaced with an artificial valve. This is major surgery carrying the risk of complications.
A type B, or type III, aortic dissection may not necessarily require surgery. Medication, such as beta blockers - these may be used to manage blood pressure - or a less invasive type of surgery, elective endovascular repair, may be performed to redirect blood flow away from the dissection.
After initial treatment for both types of aortic dissection has been carried out, long-term use of blood pressure-lowering medication will typically be required. Many people will take this medication for the rest of their lives. Hospital visits, which may include CT and MRI scans, to check-up on the condition may also be necessary.
Aortic dissection complications
If effective treatment is not received, an aortic dissection can be life-threatening. This is commonly due to internal bleeding, but can also result from damage to an organ – stemming from a lack of blood flow to the organ – stroke, or damage to the heart’s aortic valve.
Preventing an aortic dissection typically involves keeping blood pressure within a healthy range. To do this, a variety of lifestyle changes are recommended:
- Eating a healthy diet rich in vitamins, minerals, fruits and vegetables, and low in sugar, fat and carbohydrates
- Exercising regularly
- Maintaining a healthy weight
- Quitting smoking or not starting in the first place
- Avoiding drugs, such as cocaine, and other stimulants
Preventive measures are particularly recommended for people within the at-risk groups for an aortic dissection. In combination with lifestyle changes, people with a history of high blood pressure should also take care to take their prescribed medication.
Other names for aortic dissection
- Aortic tear
Columbia Surgery. “Valve Sparing Aortic Root Replacement (David Procedure).” Accessed June 29, 2018. ↩