Your aorta is the large artery that arises from the left lower chamber of the heart and provides oxygen-rich blood throughout your body. This blood vessel is made up of three layers. In certain circumstances, a tear develops in the inner layer. When this occurs, the aorta then bleeds into itself through the middle layer, extending this tear and leads to a separation of the layers of the aorta – known as aortic dissection.
Causes of Aortic dissection
Risk factors for aortic dissection include:
- High blood pressure
- The presence of an aneurysm
- Atherosclerosis (or buildup of plaque in the arteries)
- Certain genetic conditions like a bicuspid aortic valve
- Connective tissue diseases (such as Marfan syndrome) which run in families
- Traumatic injury after a car crash or from a high fall
- Family history of aortic dissection
When dissection first occurs and the layers of the aorta are forced apart, it usually feels like a severe, sharp, tearing pain in your chest and back. It feels like your aorta is ripping apart. Other symptoms include
- Shortness of breath
- Fainting or dizziness
- Rapid weak pulse
- Symptoms of stroke
Aortic dissection is life threatening. About 40 percent of patients die immediately from complete rupture and bleeding out from the aorta. The risk of dying can be as high as one to three percent per hour until the patient gets treatment. If you have symptoms of aortic dissection, severe chest pain, symptoms of stroke, call 911 or seek emergency care.
Treatment of aortic dissection depends upon the location of the tear.
Type A Aortic Dissection: This type of tear is located closer to the heart and can be life-threatening. It usually requires urgent surgery to repair or replace the first segment of the aorta (ascending aorta) where the tear started. The risk of dying from this urgent surgery is about 10 to 20 percent, depending on the condition of the patient at the time of arrival.
Type B Aortic Dissection: This type of tear is located further down the aorta (descending aorta), further from the heart, surgery may not be necessary initially, but intensive medical therapy for blood pressure control is paramount. These patients are first managed using intravenous blood pressure medications and close, careful monitoring. The need for surgical intervention may then be delayed for a matter of months to years depending on the severity of their tear. The exception occurs in patients where the downstream tear cuts off blood flow to the vital organs including the kidneys, intestines, legs or even the spinal cord. Like dissections that occur close to the heart, these patients require urgent intervention to save their lives.
Types of treatment
Surgery and Endovascular Treatment
Depending on the extent of aorta involved, a durable repair may require open surgery where the aorta is replaced with a fabric tube called a graft that is directly sewn in place of the diseased aorta. Alternatively, the surgeon may use a stent graft which is a fabric tube supported by metal wire stents (like a scaffold) to repair the aorta. The stent grafts are delivered “endovascularly” which means they are placed over a wire through a small incision in the groin and then delivered upstream into the aorta and deployed by releasing the stents like a spring.
Another option that is commonly required in patients with aortic dissections is a hybrid approach, utilizing a combination of conventional open surgery and endovascular stentgraft techniques. One of the most common hybrid procedures is called the “elephant trunk” procedure. During this procedure an open operation is performed to repair the aorta close to the heart, as well as the aortic arch – the segment of the aorta where the blood supply to the brain originates. In addition to this, an additional graft is left hanging into the descending, or downstream aorta, like the trunk of an elephant. This elephant trunk provides a durable place to land an endovascularly placed stent graft during an additional procedure. Newer hybrid procedures involve surgery and reconstruction of the aortic arch blood vessels without the use of the heart lung machine in combination with stent grafts to repair complex aortic dissections in the chest.
Medications, such as beta blockers are prescribed to lower heart rate and blood pressure . In addition other medications may be used.
Long term care
Regular follow up
Once a patient survives the initial event, either with or without surgery, regular follow-ups are critical and should include imaging at regular intervals. People who survive an aortic dissection are prone to developing aneurysms later on.
Over time, the stress of blood flow between aortic layers can cause the weakened area of the aorta to bulge like a balloon, stretching the aorta into what is called an aneurysm – with the risk for late rupture and associated death. Many patients may require future surgeries to repair late developing aneurysms.
Patients will require life-long beta blockers to manage blood pressure. Sometimes more than one blood pressure medication may be needed to reach the goal. If patients do not tolerate these medications, other blood pressure drugs will be used.
While aerobic exercise (walking, biking, and swimming) may be encouraged, you may need to avoid activities, such as weight lifting, that increase blood pressure and put added stress on the aorta.
Care at Miller Family Heart & Vascular Institute
The Cleveland Clinic Miller Family Heart & Vascular Institute has one of the largest aortic practices in the world – with experience with every aortic repair and replacement technique. Cleveland Clinic surgeons are also involved in clinical trials looking at better ways to treat aortic dissection using newer and investigational endovascular devices and hybrid surgical techniques. We are also evaluating the processes leading to dissection so that we may intervene before patients develop these life-threatening complications.