What is the treatment for an aortic aneurysm?

Treatment of Aortic Aneurysm

The treatment of aortic aneurysm is primarily based on aneurysm size, with surgical or endovascular repair indicated when the ascending aortic diameter reaches ≥55 mm in most patients, ≥50 mm in patients with bicuspid valve with risk factors, and ≥50 mm in patients with Marfan syndrome. 1

Diagnosis and Evaluation

• Aortic aneurysm is defined as a permanent and localized dilatation of the aorta exceeding 50% of its normal diameter 2
• Comprehensive imaging with CT or MRI is essential to visualize the entire aorta and identify affected segments 2
• Measurements should be taken perpendicular to the longitudinal axis of the aorta for accurate sizing 2

Risk Stratification

• The risk of rupture increases with aneurysm size, roughly doubling with every 1 cm of growth over 5 cm 1
• Aneurysms 6.0 to 6.5 cm carry a 7% annual risk of rupture 1
• Additional risk factors for rupture include:
  • Symptomatic aneurysms 1
  • Growth rate >1 cm per year 1
  • Hypertension, diabetes, and end-stage renal disease 3
  • Female sex (women more frequently rupture at smaller diameters) 3

Medical Management

• Medical management focuses on decreasing forces on the aortic wall by controlling blood pressure 1
• Optimal cardiovascular risk management is recommended for all patients with aortic aneurysms to reduce major adverse cardiovascular events 1
• Key components of medical management include:
  • Beta-blockers as foundation therapy to reduce rate of aortic dilatation 2
  • ACE inhibitors or ARBs to control blood pressure to the lowest tolerated level 2, 4
  • Statin therapy to reduce cardiovascular mortality and slow AAA growth 4
  • Smoking cessation 4, 5

Surveillance Recommendations

• For thoracic aortic aneurysms:

  • Diameter <40 mm: imaging every 4 years 1
  • Diameter 40-44 mm: imaging every 3 years 1
  • Diameter 45-49 mm: imaging every 12 months 1
  • Diameter 50-54 mm: imaging every 6 months 1

• For abdominal aortic aneurysms:

  • Diameter 25-29 mm: duplex ultrasound every 4 years 1
  • Diameter 30-39 mm: duplex ultrasound every 3 years 1
  • Diameter 40-44 mm (women) or 40-49 mm (men): annual duplex ultrasound 1
  • Diameter 45-50 mm (women) or 50-55 mm (men): duplex ultrasound every 6 months 1

Indications for Intervention

Thoracic Aortic Aneurysm

• Surgery is indicated when the ascending aortic diameter reaches:

  • ≥50 mm for patients with Marfan syndrome 1
  • ≥45 mm for patients with Marfan syndrome with additional risk factors (family history of dissection, growth rate >3 mm/year) 1
  • ≥50 mm for patients with bicuspid valve with risk factors 1
  • ≥55 mm for patients without elastopathy 1

• For aortic arch aneurysms:

  • Surgery should be considered when diameter reaches ≥55 mm 1

• For descending aortic aneurysms:

  • TEVAR (Thoracic Endovascular Aortic Repair) should be considered when diameter reaches ≥55 mm 1
  • Open surgery should be considered when diameter reaches ≥60 mm if TEVAR is not technically possible 1
  • For Marfan syndrome or other elastopathies, open surgery is preferred over TEVAR 1

Abdominal Aortic Aneurysm

• Elective repair is recommended when:
  • Diameter ≥5.5 cm in men 6, 3
  • Diameter ≥5.0 cm in women 3
  • Symptomatic aneurysms regardless of size 2

Intervention Approaches

• Endovascular repair (EVAR/TEVAR) should be considered over open surgery when anatomy is suitable, due to decreased perioperative morbidity and shorter hospital stay 1
• Open surgical repair remains important for patients with:
  • Unsuitable anatomy for endovascular repair 1
  • Failed endovascular repair 1
  • Marfan syndrome or other connective tissue disorders 1

Post-intervention Follow-up

• Lifelong imaging surveillance is essential after endovascular repair due to potential complications including endoleaks, stent graft migration, and continued aneurysm expansion 1
• For patients with mechanical prosthesis after surgical repair, follow-up at 2 years and then every 5 years is recommended 1

Common Pitfalls and Special Considerations

• More than 11% of ruptured AAAs occur in patients below the recommended size threshold for repair 3
• Patients with aortic aneurysms have a 10-year risk of mortality from other cardiovascular causes up to 15 times higher than the risk of aorta-related death 2
• Fluoroquinolones should generally be avoided in patients with aortic aneurysms unless there is a compelling clinical indication with no reasonable alternative 1