What is the current guideline for managing aortic root dilatation?

Management of Aortic Root Dilatation

Surgery is recommended in patients with dilatation of the aortic root or ascending aorta with a tricuspid aortic valve and a maximum diameter of ≥55 mm. 1

Diagnostic Evaluation

Initial Assessment

• Transthoracic echocardiography (TTE) is recommended at diagnosis to assess:
  • Aortic valve anatomy and function
  • Aortic root dimensions
  • Ascending aorta diameters 1

Advanced Imaging

• CT or MRI is recommended to:
  • Confirm TTE measurements
  • Rule out aortic asymmetry
  • Determine baseline diameters for follow-up 1
  • Evaluate the entire aorta at baseline and during follow-up 1

Frequency of Surveillance

• For thoracic aortic dilatation:
  • TTE is appropriate for monitoring the aortic root and proximal ascending aorta
  • CMR or CCT is recommended for surveillance of distal ascending aorta, aortic arch, and descending thoracic aorta 1
  • More frequent imaging (every 6 months) is recommended when approaching surgical thresholds or if diameter exceeds 4.5 cm 2

Surgical Indications

General Population (Tricuspid Aortic Valve)

• Surgery is recommended when:
  • Maximum diameter ≥55 mm 1
  • Isolated aortic arch aneurysm with diameter ≥55 mm 1

Special Populations

• Bicuspid aortic valve:
  • Surgery when diameter ≥50 mm 1
• Marfan syndrome:
  • Surgery when diameter ≥50 mm 1
  • Prophylactic surgery when diameter >45 mm in women desiring pregnancy 1
• Lower thresholds may be considered with:
  • Family history of aortic dissection
  • Growth rate ≥3 mm per year
  • Significant aortic regurgitation
  • Planned pregnancy
  • Patient preference 1

Concomitant Surgery

• For patients requiring aortic valve surgery, lower thresholds (≥45 mm) can be used for concomitant aortic replacement 1
• When open surgical repair of ascending aortic aneurysm is performed, concomitant hemi-arch replacement should be considered if dilatation extends into the proximal aortic arch (>50 mm) 1

Medical Management

Pharmacological Therapy

• In patients with Marfan syndrome:
  • Treatment with either beta-blockers or ARBs in maximally tolerated doses is recommended to reduce the rate of aortic dilation 1
  • Combined therapy with both beta-blockers and ARBs is reasonable 1
• In all patients with aortic aneurysm:
  • Optimal cardiovascular risk management is recommended 1
  • Blood pressure control (<140/90 mmHg) is essential 1

Lifestyle Modifications

• Patients with borderline aortic root diameters should:
  • Avoid strenuous physical exercise
  • Avoid competitive, contact, and isometric sports 1
• For patients with Marfan syndrome:
  • Regular moderate aerobic exercise with intensity informed by aortic diameter is recommended 1
  • Individualize physical activity based on aortic diameter and family history 1

Follow-up After Intervention

After Open Repair

• Early CT within 1 month, then yearly CT follow-up 1
• After open repair of AAA, first follow-up imaging within 1 post-operative year, then every 5 years if findings are stable 1

After Endovascular Repair

• Surveillance after TEVAR or EVAR at 1,6, and 12 months, then yearly 1
• Shorter intervals if abnormal findings require closer surveillance 1

Family Screening

• When aortic root disease is identified, screening first-degree relatives with appropriate imaging is:
  • Indicated in Marfan patients
  • Should be considered in bicuspid valve patients with aortic root disease 1

Common Pitfalls and Caveats

1. TTE is not recommended for surveillance of aneurysms in the distal ascending aorta, aortic arch, or descending thoracic aorta due to limited visualization 1
2. Even after aortic root replacement, patients remain at risk for complications in other aortic segments and require continued surveillance 2
3. Patients with small stature may require lower absolute diameter thresholds; consider using indexed measurements (aortic size index, aortic height index) 1
4. Valve-sparing operations should only be performed in experienced centers where durable results are expected 1
5. In patients with limited life expectancy (<2 years), elective AAA repair is not recommended 1

By following these guidelines, clinicians can appropriately manage patients with aortic root dilatation to reduce the risk of life-threatening complications such as aortic dissection and rupture.