Aortic Aneurysmal Disease: TAA Overview

Aortic dilation with an increase in diameter of at least 50% greater than expected for the same aortic segment in unaffected individuals of the same age and sex.

The underlying mechanism for thoracic aortic aneurysm (TAA) formation is the degeneration and fragmentation of elastic fibers in the aorta's wall.

Genetic conditions associated with TAA, such as Marfan syndrome, Loeys-Dietz syndrome, and bicuspid aortic valve (BAV).

Thorough family history can reveal TAA, syndromic conditions (like Marfan), bicuspid aortic valve, or early deaths in family members, suggesting potential genetic predisposition.

Physical examination for TAA may reveal extracardiac and cardiac features of connective tissue dysplasia, including skin abnormalities (striae, scars), musculoskeletal changes (tall stature, scoliosis), and cardiac issues like bicuspid aortic valve (BAV).

Genetic testing is recommended for patients with a positive family history of TAA, particularly those younger than 60 years old, helping diagnose syndromic conditions like Marfan and Loeys-Dietz syndrome.

Degenerative disease is the most frequent cause of TAA in older individuals, affecting the descending thoracic aorta more often than in genetic disorders. Age, sex, and body size are crucial factors when assessing aorta dimensions.

The normal rate of aortic expansion in men per decade of life.

The normal rate of aortic expansion in women per decade of life.

Inflammation of the aorta, often categorized as infectious or noninfectious.

A type of aortitis caused by an infection, typically less common than noninfectious forms.

A type of aortitis caused by autoimmune disorders or other non-infectious factors.

The most common form of aortitis in individuals older than 60, caused by inflammation of large blood vessels.

The most common form of aortitis in individuals younger than 60, affecting the aorta and its branches.

A diagnostic imaging technique that uses sound waves to create images of the heart and surrounding structures, including the aorta.

A diagnostic imaging technique that uses sound waves to create images of the heart and surrounding structures, performed from the esophagus.

A diagnostic imaging technique that uses X-rays and contrast dye to create detailed images of blood vessels, including the aorta.

A diagnostic imaging technique that uses a magnetic field and radio waves to create images of the aorta, providing information about its structure and inflammation.

A diagnostic imaging technique that uses a radioactive tracer to detect metabolically active cells in the body, valuable for identifying and monitoring inflammation in the aorta.

A standardized measurement technique for the thoracic aorta, involving the distance between the leading edges of the aortic wall.

A condition affecting the aorta, often related to age and characterized by an expansion or enlargement of the aortic wall.

Regular follow-up assessments for individuals with diagnosed aortic aneurysms or aortopathies to monitor their progress and determine the need for interventions.

For stable aortic aneurysms (AAAs) less than 4.5 cm, imaging can be spaced out to annual studies or every 1.5 to 2 years.

The primary treatment focus for patients with TAA is aggressive management of hypertension, regardless of the cause. Beta-blockers are generally used as first-line therapy, followed by losartan or other angiotensin II receptor blockers (ARBs).

Both beta-blockers and ARBs have demonstrated similar effectiveness in reducing the annual growth rate of the aorta in patients with Marfan syndrome (MFS), with an estimated 50% reduction.

Systemic treatment with either a transforming growth factor beta-neutralizing antibody or losartan, an ARB that inhibits transforming growth factor beta signaling, can attenuate or prevent the development of aortic wall pathology and dilation in TAA.

Initial treatment for giant cell arteritis (GCA) involves immunomodulatory therapies with corticosteroids, followed by long-term non-steroidal medications due to the high risk of recurrence. Tocilizumab, an anti-interleukin-6 antibody, has largely replaced steroid-sparing medications like methotrexate.

Recommendations for repair of aortitis-related aneurysms are similar to degenerative aortic disease, but long-term data is limited. These aneurysms carry a higher risk of rapid expansion and subsequent dissection. Due to the potential for graft failure in the presence of active inflammation, experts suggest achieving clinical remission before considering elective repair.

Patients with TAA should avoid contact and competitive sports, isometric exercise, and repetitive weightlifting. There is typically a recommended lifting restriction of around 50 pounds.

The Canadian Cardiovascular Society recommends preventing patients from private driving if their TAA is less than 6.0 cm or 5.5 cm for commercial drivers.

During pregnancy, repeated aortic imaging is suggested every 4 to 12 weeks, depending on the diagnosis and severity of aortic dilation. Beta-blockers are often recommended and generally well tolerated throughout pregnancy.

Elective aortic repair is recommended for patients with bicuspid aortic valve (BAV)-related TAA when the aortic dimension is greater than 55 mm, unless there are high-risk features. For patients with Marfan syndrome, the threshold for intervention is lowered to greater than 50 mm, and even lower with additional risk factors. The suggested threshold for intervention in patients with Loeys-Dietz syndrome is greater than 42 mm, though some studies suggest greater than 40 mm.