What is the management for a patient with a thoracic aortic aneurysm?

Management of Thoracic Aortic Aneurysm

For thoracic aortic aneurysms, surgical repair is recommended when the ascending aorta reaches ≥5.5 cm in degenerative disease, or at smaller thresholds (4.0-5.0 cm) in genetic syndromes, with endovascular repair (TEVAR) preferred over open surgery for descending thoracic aneurysms when anatomy is suitable. 1, 2

Surgical Intervention Thresholds

Ascending Aorta and Aortic Root

• Surgery is indicated at ≥5.5 cm for degenerative aneurysms with tricuspid aortic valve 1, 2
• Earlier intervention at 4.0-5.0 cm is required for:
  • Marfan syndrome 2
  • Loeys-Dietz syndrome (specifically 4.2-4.6 cm) 1, 2
  • Bicuspid aortic valve 2
  • Familial thoracic aortic aneurysm 2
• Concomitant aortic repair at ≥4.5 cm when undergoing aortic valve surgery 2
• Growth rate >0.5 cm/year warrants intervention even below size thresholds 2

Descending Thoracic Aorta (DTA)

• Elective repair at ≥5.5 cm for non-heritable disease 1
• TEVAR is preferred over open repair when anatomy is suitable 1
• Consider repair at <5.5 cm if high-risk features present (rapid growth, saccular morphology, symptoms) 1

Thoracoabdominal Aortic Aneurysm (TAAA)

• Repair recommended at ≥6.0 cm in low-moderate surgical risk patients 1
• Consider repair at ≥5.5 cm if high-risk features, very low surgical risk, or experienced multidisciplinary team available 1

Immediate Surgical Referral Criteria

Any symptomatic patient requires urgent surgical evaluation regardless of size 2, 3:

• Chest pain or back pain attributable to aneurysm
• Dyspnea, hoarseness, or dysphagia from compression
• Symptoms indicate impending rupture with >50% mortality if untreated 2

Surgical Techniques by Location

Aortic Root

• Valve-sparing root replacement (David or Yacoub procedure) for pliable valve cusps at experienced centers 1, 2
• Bentall procedure (composite root and valve replacement) for non-salvageable valves, requiring lifelong vitamin K antagonists if mechanical valve used 1, 2
• Coronary artery reimplantation required; monitor for coronary button aneurysms postoperatively 1

Ascending Aorta (Supracoronary)

• Supracoronary tubular graft for isolated ascending involvement above sinotubular junction 1, 2
• Shortest cardiopulmonary bypass time with relatively low complexity 1

Aortic Arch

• Hemiarch or total arch replacement depending on extent of involvement 1, 2
• Requires hypothermic circulatory arrest and cerebral perfusion strategies 1
• Highest procedural complexity and risk 1

Descending Thoracic Aorta

• TEVAR is first-line when anatomy suitable 1
• Revascularize left subclavian artery before TEVAR if coverage planned, to reduce spinal cord ischemia and stroke risk 1
• Open repair reserved for unsuitable TEVAR anatomy, connective tissue disorders, young healthy patients with long life expectancy 1

Thoracoabdominal Aorta

• Endovascular repair with fenestrated/branched endografts should be considered at experienced centers when anatomy suitable 1
• Open repair for unsuitable anatomy, requires extracorporeal circulation and spinal cord protection protocols 1

Medical Management

All patients with thoracic aortic aneurysm require aggressive cardiovascular risk reduction 1, 2:

• Strict blood pressure control (target <140/90 mmHg, lower in genetic syndromes)
• Beta-blockers preferred for heart rate control (target <60 bpm)
• Statin therapy for atherosclerotic disease
• Avoid fluoroquinolones unless compelling indication with no alternative 2

Surveillance Strategy

Pre-operative Surveillance

• Transthoracic echocardiography (TTE) at diagnosis for aortic valve and root assessment 1
• Cardiac CT or cardiac MRI for ascending aorta, arch, descending thoracic, and TAAA surveillance 1
• TTE not adequate for distal ascending, arch, or descending aorta monitoring 1

Imaging Intervals

• Aortic arch <4.0 cm: every 12 months 3
• Aortic arch ≥4.0 cm: every 6 months 3
• Growth rate ≥0.3 cm/year over 2 years or ≥0.5 cm in 1 year: urgent surgical referral 3

Post-operative Surveillance

• After open repair: CT within 1 month, then yearly for 2 years, then every 5 years if stable 1
• After TEVAR: imaging at 1 month and 12 months, then yearly 1
• Annual TTE for bioprosthetic valve monitoring 2

Critical Pitfalls to Avoid

• Never delay referral of symptomatic patients—operative mortality at experienced centers is 1-5% versus >50% mortality from rupture 2
• Do not use endovascular stent grafts for ascending aorta—not FDA approved for this location 2
• Do not rely solely on absolute diameter—index to body surface area in short stature patients, Turner syndrome, or when height >1 SD from mean 2, 3
• Do not use TEVAR in genetic/connective tissue disorders—contraindicated for elective intervention 1
• Refer to high-volume multidisciplinary aortic centers—outcomes significantly better with experienced teams 1, 2
• Screen first-degree relatives when thoracic aneurysm identified, as familial clustering common 2