What is the management and treatment for an ascending aortic aneurysm?

Management and Treatment of Ascending Aortic Aneurysm

Surgical intervention is recommended for patients with ascending aortic aneurysm when the diameter reaches 5.5 cm or greater in patients with degenerative thoracic aneurysm, and at smaller diameters (4.0-5.0 cm) for patients with genetic disorders such as Marfan syndrome, Loeys-Dietz syndrome, or bicuspid aortic valve. 1

Indications for Surgical Intervention

Size-Based Criteria

• Surgery is recommended for asymptomatic patients with degenerative thoracic aneurysm when the ascending aorta diameter is ≥5.5 cm 1
• Earlier intervention at smaller diameters (4.0-5.0 cm) is recommended for patients with:
  • Marfan syndrome 1
  • Loeys-Dietz syndrome (at 4.2 cm by TEE or 4.4-4.6 cm by CT/MRI) 1
  • Bicuspid aortic valve 1
  • Familial thoracic aortic aneurysm and dissection 1
• Concomitant repair of the aortic root or replacement of the ascending aorta should be considered when patients undergo aortic valve repair/replacement and have an ascending aorta or aortic root >4.5 cm 1

Growth Rate Criteria

• Surgical intervention should be considered when growth rate exceeds 0.5 cm/year, even if the aorta is less than 5.5 cm in diameter 1

Symptomatic Patients

• Prompt surgical intervention is recommended for patients with symptoms suggestive of aneurysm expansion, unless life expectancy is limited or quality of life is substantially impaired 1

Other Risk Factors

• Lower thresholds for intervention may be considered in cases of:
  • Growth of aortic diameter ≥3 mm per year 1
  • Resistant hypertension 1
  • Short stature (<1.69 m) 1
  • Root phenotype 1
  • Aortic length >11 cm 1
  • Age <50 years 1
  • Desire for pregnancy 1
  • Aortic coarctation 1

Surgical Techniques

For Isolated Ascending Aortic Aneurysms

• Resection and graft replacement is the most commonly performed and recommended procedure 1
• For isolated dilatation of the ascending tubular (supra-coronary) aorta, a supra-commissural tubular graft is inserted with the distal anastomosis just before the aortic arch 1

For Aneurysms Involving the Aortic Root

• The surgical approach depends on the aortic annulus and valve condition 1:
  • If the aortic valve cusps are pliable, aortic valve-sparing techniques may be recommended:
    • David procedure (reimplantation) 1
    • Yacoub technique (remodelling with aortic annuloplasty) 1
  • If the aortic valve is not salvageable, composite replacement of the aortic root and valve with the Bentall procedure is indicated 1

For Aneurysms Extending to the Arch

• For thoracic aortic aneurysms involving the proximal aortic arch, partial arch replacement together with ascending aorta repair using right subclavian/axillary artery inflow and hypothermic circulatory arrest is reasonable 1
• In patients undergoing open surgical repair of an ascending aortic aneurysm, concomitant hemi-arch replacement should be considered if the dilatation extends into the proximal aortic arch (>50 mm) 1

Medical Management

Blood Pressure Control

• Optimal implementation of cardiovascular risk management and medical treatment are recommended to reduce major adverse cardiovascular events in patients with aortic aneurysms 1
• Beta-blockers are beneficial for patients with Marfan syndrome 2

Surveillance Recommendations

• After surgical repair, follow-up imaging is essential:
  • First follow-up imaging within 1 post-operative year, and every 5 years thereafter if findings are stable 1
  • For patients with a bioprosthetic valve, annual TTE monitoring is recommended 1
  • For patients with mechanical prosthesis or native aortic valve, clinical evaluation and TTE should be performed if new heart symptoms develop 1

Important Considerations and Pitfalls

• Endovascular stent grafts have not been approved by the FDA for treatment of aneurysms or conditions of the ascending aorta 1
• The risk of operation should be weighed against the risk of rupture or dissection, which increases significantly as the aorta reaches critical dimensions 3
• Fluoroquinolones should generally be avoided in patients with aortic aneurysms but may be considered if there is a compelling clinical indication and no other reasonable alternative 1
• Aortic diameter is the major criterion for recommending elective operation, but other factors such as family history, genetic disorders, and symptoms should be considered in the decision-making process 1

Outcomes

• Current risk for ascending aortic aneurysm repair is low (<2%) whether or not the aortic root or valve also needs repair 4
• Surgical techniques have improved significantly, with 30-day mortality rates as low as 4.8% overall, and even lower (0%) for certain valve-sparing techniques 5
• With proper timing of surgery based on the guidelines, the risk of surgical complications is lower than the mortality due to rupture or dissection 2