An aneurysm is an expansion or bulge of a blood vessel to more than 1.5 times its normal size. The aorta - the body's largest artery that is responsible for carrying oxygen-rich blood away from the heart - is prone to developing aneurysms.
If an aneurysm occurs in the ascending aorta, a section of the artery close to the heart that begins at the base of the left ventricle, it is called an ascending aortic aneurysm.
- Ascending aortic aneurysms are a subtype of thoracic aortic aneurysms or aneurysms that occur in the chest area above the diaphragm.
- Ascending aortic aneurysms are the second most common type of aortic aneurysms. They are most commonly diagnosed in older adults who are in their 50s and 60s.
- If left untreated, these aneurysms can grow in size and may eventually burst, leading to serious complications and death.
- Treatment of an ascending aortic aneurysm depends on its size and rate of growth.
Thoracic aortic aneurysms may cause issues such as shortness of breath, back pain, and chest pain.
Ascending aortic aneurysms do not always cause symptoms, especially in the early stages and when small in size.
As they increase in size, thoracic aortic aneurysms may begin to cause problems such as:
- chest pain
- back pain
- tenderness in the thoracic region
- shortness of breath
Not all people with ascending aortic aneurysms will experience symptoms, even when the bulge is large.
A ruptured aneurysm, on the other hand, is a medical emergency. Symptoms include:
- difficulty breathing
- difficulty swallowing
- loss of consciousness
- low blood pressure
- rapid heart rate
- sudden and intense pain in the chest or back
- weakness or paralysis on one side of the body
Aneurysms may be caused by anything that weakens the aortic walls. Several factors can contribute to the development of an ascending aortic aneurysm and other types of aneurysms, including:
This condition occurs when plaque builds up on the artery walls, causing them to become stiff and inflexible, thereby increasing the risk that the artery walls will weaken and bulge.
Medical conditions and infection
Genetic disorders and inflammatory conditions are thought to contribute to aneurysm development in the thoracic region.
Genetic conditions that may play a role include:
- Marfan syndrome: A condition that affects the body's connective tissue and may cause weakness in the aortic wall.
- Ehlers-Danlos: A group of rare disorders that affect the connective tissue that supports the blood vessels as well as the bones, skin, and other organs and tissues.
- Loeys-Dietz: A condition similar to Marfan syndrome that not only affects the body's connective tissue but also leads to an enlargement of the aorta.
Inflammatory conditions that may increase the risk of thoracic aortic aneurysms include giant cell arteritis and Takayasu arteritis.
Untreated infection, such as salmonella poisoning, is a rare cause of an aneurysm in the aorta that is commonly known as a mycotic aneurysm.
Aortic valve issues
People with problems of the aortic valve may be more likely to experience ascending aortic aneurysms. For example, those born with a bicuspid aortic valve - where there are just 2, rather than 3, cusps of the aortic valve - may experience more pressure on the artery walls.
The types of aortic aneurysms are:
Thoracic aortic aneurysms
Aneurysms that develop in the chest area, above the diaphragm, are classed as thoracic aneurysms and may be subcategorized as either ascending or descending. Descending aortic aneurysms occur in the back of the chest cavity.
Abdominal aortic aneurysms
Aneurysms that develop in the lower part of the aorta are called abdominal aortic aneurysms. These are more common than thoracic aortic aneurysms, with abdominal aortic aneurysms comprising over 75 percent of aortic aneurysms.
Other types of aneurysm
- Thoracoabdominal aneurysms forms between the upper and lower parts of the aorta.
- Cerebral aneurysms develop in an artery in the brain.
- Peripheral aneurysms occur in the large arteries of the legs and arms.
Risk factors for developing ascending aortic aneurysm may include age, general health and smoking.
Other factors that increase the risk of developing an ascending aortic aneurysm include:
- Age: Both the risk of atherosclerosis and thoracic aortic aneurysms increase with age.
- Sex: Men are 2 to 4 times more likely than women to be diagnosed with an ascending aortic aneurysm.
- Family history: Many cases of aortic aneurysm are linked to a family history of the condition.
- General health: Those with high blood pressure and high cholesterol are at greater risk of hardening of the arteries, a risk factor for ascending aortic aneurysm.
- Smoking: Using cigarettes and other tobacco products is a major risk factor for the development of an aortic aneurysm.
An ascending aortic aneurysm is a serious health risk. It may rupture, causing internal bleeding that can be life-threatening. The larger the aneurysm, the greater the risk of rupture.
Similarly, larger aneurysms can cause aortic dissection, a life-threatening medical emergency characterized by tearing of the aortic layers.
Smaller aneurysms can lead to:
- a build up of atherosclerotic plaque at the site
- the formation of clots around the aneurysm, which increases the risk of stroke
If a doctor suspects an aortic aneurysm, they may use one or more of the following tests to confirm the diagnosis:
- CT scan
- magnetic resonance angiography (MRA)
Most ascending aortic aneurysms do not produce symptoms and therefore go undiagnosed until discovered during a doctor's visit or medical check-up.
Doctors usually treat small aneurysms with beta-blockers, a type of medication for high blood pressure. Routine tests will be required to monitor the aneurysm's progression.
Aneurysms that are large or growing rapidly will require surgery. Types of surgery include:
In this procedure, surgeons make an incision in the chest. They remove the damaged portion of the aorta and replace it with a synthetic tube called a graft. Recovery time following surgery is usually at least 4 weeks.
A less invasive form of surgery, endovascular surgery involves running a small catheter to the aorta through an artery in the leg. This catheter is then used to deliver a stent into the aneurysm, which reduces blood pressure on the artery. This procedure prevents the aneurysm from getting bigger, resulting in decreased wall tension and reduced risk of rupture.
If an ascending aortic aneurysm ruptures, emergency surgery will be required. While it is possible to repair the aorta, the risks are high, and the individual is more likely to experience complications.
The chance of developing an ascending aortic aneurysm may depend on preventative lifestyle changes.
Lifestyle changes can improve overall health and decrease the risk of developing an ascending aortic aneurysm or another type of aortic aneurysm.
Preventative steps include:
- stopping smoking
- keeping blood pressure within the healthy range
- keeping cholesterol levels within the healthy range
- engaging in regular cardiovascular activity
- managing stress levels
- maintaining a healthy weight
- reducing intake of foods high in fat, sugar, and sodium
- treating medical conditions that can raise the risk of an aortic aneurysm
People who are at increased risk of developing an aortic aneurysm, including those with a family history of the condition, should see their doctor to have regular screening tests to monitor for the formation of aneurysms.
The outlook for people with an ascending aortic aneurysm depends on several factors, including the presence of co-occurring conditions, such as heart disease, high blood pressure, and high cholesterol.
Getting treatment for these conditions, and monitoring existing aneurysms, plays a major role in recovery and the prevention of complications.