When is an aortic angiogram recommended?

Aortic Angiogram: Indications and Recommendations

Aortic angiography is indicated when non-invasive imaging techniques are inadequate or inconclusive for evaluating aortic pathology, particularly when planning surgical or endovascular interventions for aortic disease.

Primary Indications for Aortic Angiography

Diagnostic Evaluation

• Aortic angiography may be useful when morphology of the aortic sinuses, sinotubular junction, or ascending aorta cannot be assessed accurately or fully by echocardiography 1
• Indicated when there is discrepancy between clinical findings and non-invasive imaging results, particularly in patients with borderline left ventricular ejection fraction 1
• Useful when evaluating hemodynamics and severity of aortic regurgitation if echocardiographic images are suboptimal 1

Pre-Intervention Planning

• Recommended for pre-operative planning in patients undergoing aortic valve repair to evaluate leaflets and aortic root 1
• Indicated when planning endovascular or surgical interventions for aortic aneurysms to define optimal approach 1
• Useful for identifying associated vascular abnormalities such as renal artery stenosis, multiple renal arteries, or occlusive lesions that may affect surgical planning 2

Limitations and Alternatives

Preferred Non-Invasive Alternatives

• CT angiography (CTA) has become the preferred imaging test for various aortic conditions due to excellent spatial resolution, rapid image acquisition, and wide availability 3
• MR angiography (MRA) is recommended when CT cannot be performed (e.g., in patients with contrast allergy) 1
• Transthoracic echocardiography (TTE) is the first-line imaging modality for aortic root evaluation, particularly in patients with Marfan syndrome 1

Limited Utility Scenarios

• Conventional angiography has very limited utility in pre-intervention evaluation of abdominal aortic aneurysms 1
• Not recommended for routine diagnosis of acute aortic dissection as non-invasive methods have replaced angiography 4
• Coronary angiography in the setting of acute type A aortic dissection may cause considerable delay to surgery without improving outcomes 4

Special Considerations

Surveillance Protocols

• For patients with Marfan syndrome, TTE is recommended at least annually for aortic root diameter <45 mm without risk factors, and every 6-12 months for aortic root diameter ≥45 mm 1
• In patients with bicuspid aortic valve and aortic dilation >4.5 cm, annual imaging is recommended 1
• For patients with vascular Ehlers-Danlos syndrome, regular vascular surveillance of the aorta and peripheral arteries by duplex ultrasound, CT, or MRI is recommended 1

Risk Assessment

• In patients with aortic root/ascending aneurysms or thoracic aortic dissection, gathering family history information for at least three generations about thoracic aortic dissection is recommended 1
• Genetic testing should be considered in patients with heritable thoracic aortic disease 1

Clinical Pathway for Aortic Imaging

1. Initial Evaluation: Start with TTE for assessment of aortic valve and root 1
2. Secondary Imaging: If TTE is inadequate, proceed to CTA or MRA 1
3. Consider Angiography When:
   • Planning endovascular intervention 1
   • Non-invasive imaging is inconclusive 1
   • Need to evaluate branch vessel involvement 2
   • Assessment of hemodynamics is required 1

Common Pitfalls and Caveats

• Angiography may underestimate the true size of an aneurysm due to intraluminal thrombus 2
• Signal loss can occur in MRA with slow or turbulent flow conditions 5
• Conventional angiography carries risks of contrast nephropathy, particularly in patients with renal dysfunction 1
• Coronary angiography in acute aortic dissection may cause dangerous delays to definitive surgical treatment 4