What predicts and manages aortic root dilation?

From the Guidelines

Aortic root dilation is best predicted and managed through regular imaging surveillance, medication therapy, and lifestyle modifications, with the most recent guidelines recommending annual imaging surveillance and prophylactic aortic root replacement for aneurysm disease to prevent type A dissection and improve survival in Marfan syndrome 1.

Predictive Factors

The predictive factors for aortic root dilation include:

• Marfan syndrome
• Bicuspid aortic valve
• Family history of aortic dissection
• Hypertension
• Genetic mutations in genes such as FBN1, TGFBR1, and TGFBR2

Management Strategies

The management strategies for aortic root dilation include:

• Regular imaging surveillance with echocardiography or CT/MRI imaging, with follow-up intervals determined by the rate of dilation (typically every 6-12 months) 1
• Medication therapy with beta-blockers, such as atenolol (25-100 mg daily) or metoprolol (25-200 mg daily), as first-line treatment 1
• Angiotensin receptor blockers (ARBs) like losartan (50-100 mg daily) are also effective, particularly in Marfan syndrome 1
• Lifestyle modifications, including avoiding strenuous isometric exercise, competitive sports, and activities with risk of bodily collision 1
• Surgical intervention is typically recommended when the aortic root diameter reaches 5.0-5.5 cm in the general population, or 4.5-5.0 cm in those with genetic disorders like Marfan syndrome 1

Key Recommendations

• Patients with Marfan syndrome should undergo echocardiographic measurement of the aortic root dimension every 6 to 12 months, depending on aortic size 1
• Athletes with aortic dimensions mildly above the normal range should undergo echocardiographic or MRA surveillance every 6 to 12 months 1
• Prophylactic aortic root replacement for aneurysm disease prevents type A dissection and improves survival in Marfan syndrome 1

From the Research

Predictors of Aortic Root Dilation

• Aortic root dilation can be caused by various congenital or acquired conditions that lead to weakening of the aortic wall 2
• Factors that predict aortic root dilation include:
  • Congenital heart disease, particularly bicuspid aortic valve 2
  • Connective tissue disorders such as Marfan syndrome, Loeys-Dietz syndrome, and Ehlers-Danlos syndrome 2, 3, 4, 5
  • Chromosomal abnormalities, such as Turner syndrome 2
  • Essential hypertension, particularly in women with left ventricular hypertrophy and higher diastolic blood pressure 6
  • Obesity and higher stroke volume index 6

Management of Aortic Root Dilation

• Evaluation by a clinical geneticist is recommended in patients with aortic dilation, given the high frequency of associated genetic conditions 2, 4
• Anti-renin-angiotensin system (anti-RAS) therapy may be associated with a higher probability of normalizing aortic root dimension 6
• Regular echocardiograms may not be warranted for pediatric patients with hypermobile Ehlers-Danlos syndrome, given the low prevalence and lack of progression of aortic root dilation in this population 3
• Updated therapeutic strategies, including early diagnosis and treatment, aim to improve patient survival and quality of life in syndromic aortic diseases such as Marfan, Loeys-Dietz, and vascular Ehlers-Danlos syndrome 5