Thoracic aortic aneurysm

Overview

Thoracic aortic aneurysm, also known as thoracic aneurysm, occurs when the artery wall in the aorta weakens and abnormally widens or bulges as blood flows through it. An aneurysm happens when the vessel becomes significantly enlarged. This can be life-threatening.

The aorta is the body’s biggest artery and the blood vessel that transports oxygen-rich blood from the heart to the rest of the body. When aneurysm develops in the aorta, it can lead to serious health risk. Complications of a thoracic aortic aneurysm include aortic rupture or a tear between the layers of the aortic wall (aortic dissection). Rupture or dissection might result in sudden death.

Thoracic aortic aneurysm is less prevalent than abdominal aortic aneurysms. It can generally be treated with surgery or other less invasive procedures if diagnosed in time. The kind of treatment is determined by the cause, size, and rate of expansion of the thoracic aortic aneurysm.

Symptoms

A thoracic aortic aneurysm may go unnoticed since it rarely causes symptoms and often develop slowly. Although some aneurysms may grow larger over time, most start out small, which can make diagnosis difficult. Only about half of patients with thoracic aortic aneurysms report symptoms. Potential warning signs include:

• Pain in the chest or back
• Cough
• Hoarseness
• Shortness of breath

Some aneurysms never rupture or cause a dissection. If they do, common symptoms include:

• Pain in the jaw, neck, and upper back
• Breathing difficulties
• Low blood pressure
• Loss of consciousness
• Shortness of breath
• Swallowing difficulties

Aortic dissection or aneurysm rupture is a medical emergency. If you suspect a tear or rupture, seek immediate medical assistance. If you persistently experience any signs or symptoms, it is recommended that you consult a medical professional for proper diagnosis and medical intervention. Thoracic aortic aneurysms can be fatal if left untreated.

Causes

A thoracic aortic aneurysm is a type of aneurysm that arises in the chest. It occurs when the wall of an artery in the aorta weakens, causing it to unnaturally swells or bulges as blood is pumped through it. Aneurysms can form anywhere in the thoracic aorta, including near the heart, in the aortic arch, and in the lower section.

A bulge or ballooning of the aorta can be classified as fusiform or tubular aneurysm and saccular aneurysm. A fusiform is uniform in shape, appearing equally along the aorta’s extended section and margins. In saccular aneurysm, there is a small, lopsided blister on one side of the aorta that occurs in a weakened section of the aortic wall.

The aorta, the body’s largest artery that connects the heart to the abdomen, is prone to aneurysms which can develop at various locations along its length. Aneurysms can occur in the thoracic aorta, which runs through the chest, including near the heart, in the aortic arch, and in the lower part of the thoracic aorta. Abdominal aortic aneurysms are another type of aneurysm that occurs in the segment of the aorta that passes through the abdomen. In contrast, thoracoabdominal aortic aneurysms affect the aorta as it passes through both the chest and the abdomen.

Thoracic aortic aneurysms can be caused by a variety of factors, including:

• Atherosclerosis: Thoracic aortic aneurysms are commonly caused by atherosclerosis, which is prevalent among the elderly. Atheromatous plaque, a sticky substance, forms in the artery walls and stiffens and weakens the aorta over time. Although arteries are generally smooth on the inside, atherosclerosis may develop as a person ages. High blood pressure and cholesterol levels increase the risk of atherosclerosis.
• Genetic conditions: Aortic aneurysms in young persons are often inherited. Certain disorders can damage the layers of the aortic wall, increasing the risk of thoracic aortic aneurysms. Examples of hereditary connective tissue disorders include Marfan syndrome and Loeys-Dietz syndrome. Marfan syndrome, which is a hereditary disorder that affects connective tissue in the body, can weaken the aortic wall.
• Blood vessel inflammation: Inflammatory conditions of blood vessels, such as giant cell arteritis and Takayasu arteritis, are associated with thoracic aortic aneurysms.
• Irregular aortic valve: People who are born with an aortic valve, which has two flaps instead of three (bicuspid aortic valve) are more likely to develop a thoracic aneurysm. The aortic valve connects the lower left chamber of the heart to the aorta.
• Untreated infection:  Untreated infections such as syphilis or salmonella have the potential to result in a thoracic aortic aneurysm.
• Traumatic injury: Trauma such as a severe fall or car accident can lead to a thoracic aortic aneurysm.

Aortic emergencies 

Aortic dissection is a serious medical condition that occurs when the layers of the aorta, the body’s largest artery, tear and separate from each other. While having an aortic aneurysm can increase the risk of aortic dissection, it can also happen in individuals with a normal sized aorta.

The symptoms of aortic dissection can be sudden and intense, causing severe, sharp, tearing pain in the chest or upper back. However, in some cases, there may be no noticeable symptoms.

High blood pressure is a common risk factor for aortic dissection, as it causes increased blood flow that can force the layers of the aortic wall apart. If left untreated, aortic dissection can weaken the aorta, leading to the development of a thoracic aortic aneurysm. The weakened area of the aorta may bulge and stretch like a balloon, putting the individual at risk for a fatal rupture.

In case you experience any symptoms of a thoracic aortic aneurysm or aortic dissection, it’s imperative to inform your healthcare provider without delay. These medical conditions can have life-threatening consequences if left untreated and may result in a fatal rupture. Therefore, seeking prompt medical attention is crucial to minimize the risk of severe complications.

Risk factors

There are several risk factors associated with thoracic aortic aneurysm, which include:

• Age: Thoracic aortic aneurysms are most common in adults over the age of 65. The risk generally rises with age.
• Family history: According to recent studies, a significant number of aneurysms have familial patterns and can be inherited from past generations. Aneurysms can also occur at an early age.  Having a family history of aortic aneurysm in a parent, sibiling, or child increases the likelihood of developing an aortic aneurysm and the risk of rupture.
• Tobacco use: People who smoke have higher risk of developing thoracic aortic aneurysm.
• High blood pressure:  The risk of an aneurysm increases with high blood pressure.
• Buildup of plaques in the arteries: Excess plaque can develop as the person gets older. Fat and other substances in the blood can cause damage to the lining of a blood artery, raising the risk of an aneurysm.
• Genetic conditions: There is an increased risk of aortic or other blood vessel dissection or rupture on people who have specific genetic disorders. These include Marfan syndrome or a similar disorder, such as Loeys-Dietz syndrome or vascular Ehlers-Danlos syndrome.
• Bicuspid aortic valve: Aortic valves having two cusps rather than three enhance the likelihood of aortic aneurysm.