Acute Aortic Disease.. - Index of

10 Nienaber and Ince
Figure 4 Curves showing Kaplan-Meier survival for 34 patients after urgent surgery for
acute type B aortic dissection and survival for an age- and gender-matched population.
Source: From Ref. 45.
no hospital mortality, 3.4% paraplegia, an 18% incidence of false lumen patency,
and excellent long-term survival (Table 4 and Fig. 4). The ability to formulate
such precise estimates of clinical course reflects the increased anatomic precision
of the subgroupings in Lansman’s scheme.
European Working Group Classification
New studies demonstrated that intramural hemorrhage, IMH, and aortic ulcers may
be signs of evolving dissections or dissection subtypes. Consequently, a new differentiation
has been proposed by the European Working Group (Fig. 5) (54,55):
1. class 1: classical aortic dissection, with an intimal flap between true and
false lumen
2. class 2: medial disruption with formation of IMH/hemorrhage
3. class 3: discrete/subtle dissection without hematoma, eccentric bulge at
tear site
4. class 4: plaque rupture leading to aortic ulceration, penetrating aortic
atherosclerotic ulcer with surrounding hematoma, usually subadventitial
5. class 5: iatrogenic and traumatic dissection
Classic Aortic Dissection (Class 1)
Classic acute aortic dissection is characterized by the rapid development of an
intimal flap separating the true and false lumen (56). Due to the pressure difference,
the true lumen is usually smaller than the false lumen. Intimal flap tears
characterize communicating dissections. However, tears are not always found, and