Acute Aortic Disease.. - Index of

14 Nienaber and Ince
dissection, surgical care should be instituted as early as possible during this acute
phase, because mortality of type A dissection can reach up to 2% per hour in the
initial 24 hours and seems to level off gradually with time thereafter; it makes
little sense to wait and waste time to reach a subacute stage in this precarious
situation. Any type A scenario will benefit from swift transfer to a surgical center
for definitive care.
Subacute Phase
Again, by convention, the so-called “subacute phase” is an arbitrarily chosen
interval between 14 days after clinical onset and one month. Few patients with
type A or proximal dissection reach that subacute phase without urgent surgical
repair (Fig. 7). Conversely, distal dissections of the Stanford type B scenario often
reach the subacute phase of the dissection process. All-cause mortality of type B
dissection within one month of clinical impact is ∼10% according to the IRAD data
(Fig. 2). Many cases of type B dissection actually reveal a stable clinical course
once the acute phase has passed, under conservative management (including
Figure 7 Statistics from the International Registry of Acute Aortic Dissection show that
mortality of medical treatment of type A dissection is extremely high both in-hospital and
during follow-up and clearly surpasses mortality of type B dissection during a median
follow-up of 357 days. Swift surgical repair is much more rewarding for patients with
type A dissection than for type B dissection in whom the most beneficial therapy is still
unresolved and under debate.