AORTIC DISSECTION CLASSIFICATION - DeBakey and Stanford
(Myura Nagendran1, Robert Ibe2)
Whilst uncommon, acute aortic dissection can potentially be very serious with an early mortality of 1 percent per hour if left untreated. Successful management requires accurate diagnosis and early intervention.
The two commonest classification systems include the DeBakey and Stanford classifications. It is important to distinguish between the types, as dissections involving the ascending aorta generally require surgery while those of the descending aorta usually involve medial management.
DeBakey Classification
Type | Site of Origin and Extent of Aortic Involvement
|
I | Originates in the ascending aorta, propagates at least to the aortic arch and often beyond it distally
|
II | Originates in and is confined to the ascending aorta
|
III | Originates in the descending aorta and extends distally down the aorta or, rarely, retrograde into the aortic arch and ascending aorta
Type IIIa: involves thoracic descending aorta only Type IIIb: involves whole of descending aorta
|
Stanford Classification
Type | Site of Origin and Extent of Aortic Involvement
|
Type A | All dissections involving the ascending aorta, regardless of the site of origin of primary tear; even if descending aorta is also involved.
|
Type B | All dissections not involving the ascending aorta
|
Advocates of the simpler Stanford system state that ascending aorta involvement is functionally the most important determinant for deciding treatment. However, critics maintain that the distal extent of dissection in type A patients can also be important. In any case, it is worth noting that neither system provides clarity for dissections originating or limited to the aortic arch.
Type A dissections make up approximately two-thirds of cases with the remainder made up by distal dissections.
Therapeutic management differs between acute and chronic dissections as mortality and progression risk decrease with time. The vast majority of aortic dissections are acute at diagnosis. Duration of aortic dissection is defined as the length of time from symptom onset to medical assessment. It is classified as follows:
Duration | Presentation
|
Acute | Within 2 weeks |
Chronic | After 2 months |
Sub-acute | From 2 weeks to 2 months |
References
- Braunwald et al. (2005). Braunwald’s Heart Disease, A textbook of Cardiovascular Medicine. 7th edition. Elsevier Saunders.
- Cohn et al. (2007). Cardiac Surgery in the Adult. 3rd edition. McGraw-Hill Medical.
- Meszaros et al. (2000). Epidemiology and clinicopathology of aortic dissection. Chest. 117, 1271-1278.
- Ramanath et al. (2009). Acute aortic syndromes and thoracic aortic aneurysm. Mayo Clin Proc. 84, 465-481.
Posted: 1st March 2010
1 - Myura Nagendran - 3rd year student, Cambridge University
2 - Robert Ibe - CT2 Cardiac Surgery, Brighton