- Spontaneous longitudinal separation of aortic intima and adventitia by circulating blood having gained access to the media of the aortic wall splitting it in two
- Peak age: 60 years, M;F = 3:1
- Predispositions:
1. Hypertension --> stresses aortic tissue, making it more susceptible to tearing
2. Marfan Syndrome & Ehlers-Danlos syndromes affecting connective tissue
3. Valvular aortic stenosis
4. Turner Syndrome causing heart problems & high blood pressure
5. Coarctation: narrowing of the aorta , the left ventricle has to work harder and have higher pressure
6. Bicuspid aortic valve, S/P prosthetic valve
7. Trauma (rare) / mechanical injury due to Catheterization
8. Haemodynamic changes in Pregnancy (increased total circulatory volume, increased systemic blood pressure, and structural changes in the aortic wall secondary to the hormonal effects of estrogen and progesterone)
9. Cocaine Abuse (raises blood pressure)
Presentation:
- Sharp tearing anterior
– Posterior chest pain radiating to jaw, neck, lower back
- Murmur from aortic regurgitation
- Asymmetric peripheral pulses & blood pressures
- Absent femoral pulses, reappearing after re-entry
- Pulse deficit
- Hemodynamic shock
- Persistent oliguria
- Congestive heart failure due to acute aortic insufficiency
- Recurrent arrhythmias
Types of Dissections:
DeBakey:
- Type I: ascending aorta + portion distal to arch
- Type II: ascending aorta only
- Type III: descending aorta only
Subtype IIIA: up to diaphragm
Subtype IIIB: below diaphragm
Stanford:
-Type A (60-70%): ascending aorta ± arch in first 4 cm in 90%
-Type B (30-40%): descending aorta only
Modalities:
- CXR
- CT (gold standard)
Treatment:
-Surgical repair: bypass/grafting
-Medicinal: Blood pressure and contractility control using beta blockers and Nitroprusside
-Endovascular Repair: (Abdominal Aorta)
References:
Dahnert, W. (2008). Radiology Review Manual (6th Edition). Philadelphia: Lippincott Williams & Wilkins
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