5.2. Proposed management of unTBAD patients
TEVAR is the treatment of choice in coTBAD (ESC guidelines: class I,
level of evidence C) (46) for patients with appropriate anatomy (46, 56,
57). It is most effective for aortic remodelling unTBAD in the acute and
subacute stages (1), and is also recognised as a treatment to prevent
future aortic complications in unTBAD (ESC guidelines: class IIA, level
of evidence B) (46). Therefore, the most pertinent risk factors for
unTBAD progression to coTBAD should inform candidate selection for
TEVAR. At present, there are no clear clinical guidelines using
risk-stratification to inform the selection of unTBAD patients for
TEVAR. A recent systematic review and meta-analysis (58) has also
highlighted that reporting of false lumen status, aortic diameters and
growth, and demographic data has not always been congruent with the most
recent recommendations published by the Society for Vascular Surgery and
Society of Thoracic Surgeons (59). Given that these recommendations are
adhered to in future, discussion on optimal unTBAD patient selection for
TEVAR will become increasingly granular and allow for the formulation of
strong evidence-based guidelines.
In the interim, we reason that the risks quantified in Tables 2
& 3 could inform the execution of the treatment algorithm shown inFigure 4 . It is imperative to focus on high-risk imaging
features identified in Table 3 (e.g., primary entry tear
diameter >10 mm, initial total aortic diameter ≥ 40 mm,
false lumen ≥ 22 mm, patent false lumen) which are likely to indicate
unstable disease in apparently clinically stable patients (36, 42, 60).
If the imaging features are present, demographic, clinical and
laboratory parameters (Table 2 ) could then be considered.Figure 4 outlines a pragmatic approach towards TEVAR
intervention given its procedural risks and requirement for specialist
aortic care; thorough patient imaging could guide the selection of
patients at high risk of disease progression for deferred endovascular
treatment within the 14 to 90 day subacute phase which appears to be the
optimal TEVAR intervention time (1). Moreover, specific subsets of acute
unTBAD patients that are at high risk of developing downstream aortic
complications may qualify for early prophylactic endovascular therapy.
Table 2. Clinical and laboratory parameters in unTBAD patients
that could be used to predict need for intervention. HR: Hazard ratio;
OR: Odds Ratio; FDP: Fibrin degradation products.