In patients with organ or limb malperfusion, coverage of the proximal entry tear will usually expand the true lumen and re-perfuse ischemic organs. Patency of the FL both in ascending and descending aorta is not uncommon and is considered to herald unfavorable long-term outcomes [
29,
30]. In the absence of thrombosis and remodeling, further dilatation and rupture are likely [
31‐
33]. Thus, it appears logical to induce complete FL thrombosis to fully manage aortic dissection and improve outcomes [
34] in the long-term, knowing that incomplete or partial FL thrombosis and a patent FL promote further expansion and possibly subsequent rupture (RR 2.69,
P = 0.002) [
29]. The classic endovascular approach is the occlusion of connections between true and FL by additional stent-graft coverage, or by custom-made fenestrated and branched endografts at the level of abdominal re-entries [
35]. This method affords FL thrombosis throughout the dissected thoraco-abdominal aorta [
36], but carries significant risks, especially for spinal cord ischemia, as many segmental arteries may be covered. Recently, alternatives were introduced including “candy-plug” and “knickerbocker” techniques, relying on FL obstruction by prohibiting distal FL backflow [
37,
38]. Both techniques have drawbacks, have not been tested in larger series, and are considered more traumatic and potentially risky. Similarly, the use of multilayer stent technology would not be safe or appropriate as side branches and communications are likely to stay open [
39,
40]. More interestingly, a recent “true lumen intervention” suggests tackling distal re-entry sites by small stent-grafts to promote thrombosis of the FL [
41].
Conversely, the FLIRT concept uses technology applied to the FL in order to promote remodeling; it ranges from injection of embolizing material to deployment of coils, plugs alone, or in combination, as integral components of FL intervention [
42,
43]. Onyx® is the most common embolizing agent and has previously been used with coils to promote FL thrombosis and seal endoleaks [
44,
45].
In the ascending aorta, the FLIRT concept provides additional endovascular options. FLIRT has proven safe and feasible in 5 attempted cases of chronic type A dissection and is certainly less traumatic than other techniques including stenting of ascending aorta [
43]. Closure of entry tears, restoration of single-lumen blood flow, and enhanced FL thrombosis may reap long-term benefits [
11], without the risks of stent-grafting the ascending aorta (Fig.
2). Hence, the FL channel is an alternative pathway to allow a catheter to reach the tear to deploy coils and Amplatzer™ vascular occluder devices in the FL. In our series 2 Amplatzer™ Septal Occluders, 2 Amplatzer™ PFO Occluders, 1 Amplatzer™ Vascular Plug II, and 1 Amplatzer™ Duct Occluder II were used. The criteria to choose these devices were individualized to the anatomical characteristics of any given patient and to the access sites needed for different sizes of delivery systems of those devices. The sustainability of FLIRT as a concept to promote remodeling may be controversial and longer follow-up is certainly needed. Advanced interventional skills, with formal training in interventional cardiology, are also essential for safety interventions. Finally, the best timing of FLIRT as a complimentary intervention is not clear yet, but a better understanding of CT imaging may help to identify patients likely to benefit from FLIRT [
46,
47].