From the Guidelines
The dilated aortic root is most commonly caused by genetic disorders, such as Marfan syndrome, which is characterized by fibrillin-1 gene mutations that weaken connective tissue, as well as other conditions like Loeys-Dietz syndrome, Ehlers-Danlos syndrome, and familial thoracic aortic aneurysm syndromes 1.
Causes of Dilated Aortic Root
The causes of a dilated aortic root can be categorized into several groups, including:
- Genetic disorders: Marfan syndrome, Loeys-Dietz syndrome, Ehlers-Danlos syndrome, and familial thoracic aortic aneurysm syndromes are all associated with aortic root dilation 1.
- Congenital heart defects: Bicuspid aortic valve, which affects 1-2% of the population, can lead to aortic root dilation 1.
- Acquired causes: Hypertension, atherosclerosis, and inflammatory conditions like giant cell arteritis and Takayasu arteritis can all contribute to aortic root dilation 1.
- Degenerative changes: Aging-related degenerative changes, such as progressive elastin fragmentation and collagen deposition, can reduce aortic wall elasticity and lead to dilation 1.
- Other factors: Pregnancy, trauma, infections, and certain medications can also contribute to aortic dilation 1.
Importance of Monitoring and Blood Pressure Control
Regular monitoring with echocardiography or CT imaging is essential for at-risk individuals, and blood pressure control is crucial for preventing progression of aortic root dilation 1. The American Heart Association provides guidelines for prophylactic replacement of the aorta based on aortic diameter or rapid aortic enlargement 1.
Key Findings and Recommendations
The most recent and highest quality study 1 recommends regular imaging surveillance to measure the aortic diameter, status of the aortic valve, and cardiac functional status in children with aortopathy. Key findings from this study include:
- Aortic root aneurysms are present in up to 98% of patients with Loeys-Dietz syndrome.
- Arterial tortuosity is a distinguishing feature of Loeys-Dietz syndrome.
- Ehlers-Danlos syndrome also predisposes to aortic dissections.
- Nearly 25% of people with bicuspid aortic valve may experience severe aortic valve dysfunction, ascending aortic aneurysm, cardiac death, hospital admission for heart failure, and aortic dissection or rupture.
From the Research
Causes of Dilated Aortic Root
- Marfan syndrome and Ehlers-Danlos syndrome are two connective tissue vascular diseases that can cause a dilated aortic root 2
- These conditions can lead to aortic aneurysms and dissections, which can result in a dilated aortic root 2, 3
- The aortic root can become dilated due to the weakening of the aortic wall, which can be caused by genetic mutations or other factors associated with Marfan syndrome and Ehlers-Danlos syndrome 2
- Aortic surgery outcomes for patients with Marfan syndrome and Ehlers-Danlos syndrome can be affected by the underlying connective tissue disorder, leading to a higher rate of procedural complications and increased length of stay and cost 2, 3
Risk Factors
- Genetic mutations associated with Marfan syndrome and Ehlers-Danlos syndrome can increase the risk of a dilated aortic root 2
- A family history of aortic aneurysms or dissections can also increase the risk of a dilated aortic root 2
- Other factors, such as hypertension and atherosclerosis, can also contribute to the development of a dilated aortic root 3
Surgical Outcomes
- Patients with Marfan syndrome and Ehlers-Danlos syndrome who undergo aortic aneurysm repair may have a higher rate of procedural complications and increased length of stay and cost compared to patients without these conditions 2, 3
- The type of surgical repair, such as open or endovascular repair, can also affect outcomes for patients with Marfan syndrome and Ehlers-Danlos syndrome 3