Narrowed Aorta

Gregory Kicska, MD, PhD

DIFFERENTIAL DIAGNOSIS

Common

Less Common

Rare but Important

ESSENTIAL INFORMATION

Key Differential Diagnosis Issues

Focal outer diameter narrowed in coarctation or vasculitis
Diffuse outer diameter narrowing can occur in vasculitis
Normative data should be consulted to exclude common pitfall of misinterpreting normal aortic dimension for small body as abnormal
For > 45 years, aorta considered abnormally small if diameter at level of main pulmonary artery < 24 mm for ascending and < 18 mm for descending aorta
- Larger diameters may still be abnormal if older age, larger body surface area (BSA), or male

Helpful Clues for Common Diagnoses

Coarctation of Aorta
- Focal narrowing occurs below ductus arterious in adults, at ductus arterious with arch hypoplasia in neonates
- Dilated collaterals (intercostal, internal thoracic) indicate hemodynamically significant coarctation
- Treated coarctation patients can have restenosis
- Associated with bicuspid aortic valve, Turner syndrome, Marfan syndrome
Pseudo-coarctation
- Redundant aorta with narrowing distal to left subclavian origin without hemodynamic effect
- No rib notching, cardiomegaly, or collateral vessels
- Dilated brachiocephalic artery and high arch often present

Helpful Clues for Less Common Diagnoses