Familial aortic aneurysm (FAA) refers to a genetic predisposition to thoracic aortic aneurysm or dissection in the absence of other syndromes such as Marfan or Loeys-Dietz. Studies show that there is a higher rate of aortic aneurysm or dissection among people who have relatives who have experienced this condition, which suggests a genetic link.
What are aortic aneurysms and dissections?When the aorta enlarges and stretches, it becomes prone to an aortic dissection (tear). A dissection is a separation or tear in the lining of the artery that allows blood to flow between the inner and outer walls of the vessel but remains contained in the aorta. A dissection can occur spontaneously without the presence of aneurysm and, in some cases, can cause an aneurysm. Aortic rupture of an aneurysm or dissection results can lead to death if treatment (most commonly surgery) is not given immediately.
An aortic aneurysm is the ballooning, enlargement or dilation of the aorta, the main blood vessel that carries blood away from the heart.
The aorta is a long blood vessel. Aneurysms and dissections can occur in different sections of the aorta.
What are the different types of aneurysms and dissections?
The aorta can be categorized into two major areas. The thoracic aorta consists of the ascending aorta leading up from the heart (#1 in diagram), the aortic arch (#2) and the descending aorta (#3) leading down from the heart. The abdominal aorta (#4) begins as the descending aorta passes the diaphragm into the abdomen.
Aneurysms and dissections are usually named by the location on the aorta where they occur, such as thoracic aortic aneurysm or abdominal aortic aneurysm.
Dissections are also categorized by their location on the aorta where they occur. Other categories used to describe location on the aorta are type I, II and III
Type I: originates in the ascending aorta, continues to the aortic arch and often beyond it
Type II: originates in -- and is confined to -- the ascending aorta
Type III: originates in the descending aorta and extends down the aorta or, rarely, up into the aortic arch and ascending aorta
What are the symptoms of an aortic aneurysm or dissection?
Aortic aneurysms usually do not cause any symptoms until they are quite large.
Aortic aneurysms can cause the following symptoms:
Upper back pain
Coughing and wheezing
Swelling in neck or arms
Horner’s syndrome (constricted pupil, drooping eyelid and dry skin on one side of the face
Deep boring pain or pulsation in the lower back region
Aortic dissection symptoms usually appear suddenly and include:
Severe onset of sharp, stabbing, tearing or ripping pain usually in the chest (front, back or both) or lower back depending on the site of the dissection.
Decreased ability to move or decreased sensation in an arm or leg or other part of the body.
Rapid pulse, sweating, nausea, vomiting, dizziness, fainting shortness of breath, weak or absent pulse.
In some instances, there may be no pain but a sense that there is something terribly "wrong."
How are aortic aneurysms and dissections treated?
In families with a genetic history of aortic aneurysms or dissections, it is recommended that family members at risk have their aortic root (first part of the ascending aorta) monitored by echocardiography (picture using sound waves to evaluate the size of the root and how the aortic valves are working) and the parts of the aorta further from the heart, specifically the aortic arch and descending aorta monitored by CT scan or MRI at least once a year.
Once an aortic aneurysm or dissection is detected, imaging may be performed more often. The frequency will be based on several parameters and will be different for each patient. For example, more frequent monitoring is required if the aneurysm continues to increase in size, if rapid growth is observed, if aneurysm approaches critical sizes, if aortic valve function is compromised or if the individual's aorta is approaching a size at which there is a family history of aortic dissection or rupture.
Because aortic dilation occurs in a subset of individuals with bicuspid aortic valves, yearly monitoring by echocardiogram to access valve function and aortic root diameter is recommended.
Medication, such as beta-blockers, to lower blood pressure and decrease the forcefulness of the heartbeat are often recommended to slow down enlargement or to hopefully prevent dissection of the aorta. Treatment with calcium channel antagonists should be considered in individuals who cannot tolerate beta-blockers.
If the aortic diameter increases rapidly or reaches a critical size (between 4.5 - 5.0 cm), elective surgery is recommended to prevent rupture. This involves surgically replacing the damaged portion of the aorta and sometimes repairing or replacing of the aortic valve. Elective surgery, prior to a dissection, is usually very successful in centers where there is experience with the procedure.
In addition to absolute size, the rate of growth of the aorta, function of aortic valve and family history of dissection are used to determine timing of elective repair.
Aortic dissections require immediate medical attention. In some instances, management with medication is possible. Surgery may be required depending on the location and the medical circumstances.
Emergency surgery is required for ascending aortic dissections (Type A or proximal dissections). Descending aortic dissections may require emergency surgery. Patients must be transferred and evaluated at a tertiary hospital capable of performing the surgery. If the aorta ruptures as a result of an aneurysm or dissection, it is a life-threatening problem that requires immediate surgery.
If a person experiences an aortic dissection, all first degree relatives (parents, siblings, children) should be evaluated for FAA or other conditions that can cause aortic dissection.
For more information:
In addition to the above information created by the NMF, we recommend the video “Aortic Dissection at Any Age: The Tyler Kahle Story.” This moving and powerful video addresses one family’s story of loss related to Familial Aortic Aneurysm (FAA), and how they have partnered with the hospital to prevent missed aortic dissection in the future. This video was produced by Methodist Hospital in Omaha, NE.
You may also wish to visit The John Ritter Foundation for Aortic Health, founded by John's widow Amy Yasbeck and their family to raise awareness of aortic dissection.