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Page 2 of 15 Rodrigues et al. Vessel Plus 2024;8:10 https://dx.doi.org/10.20517/2574-1209.2023.109

[3]
invasive procedures . This review brings a comprehensive review of the endovascular treatment of TAAA,
presenting a brief historical perspective in addition to anatomical and clinical features relevant to technical
success and device selection.

HISTORIC PERSPECTIVE
TAAA repair was first performed by Michael E. DeBakey at the Baylor College of Medicine, Methodist
[4]
Hospital, in 1953 . In the subsequent decades, E. Stanley Crawford was responsible for refining the
technique by developing many surgical concepts and a classification system that carries his name, all of
[5,6]
which remain relevant today [Figure 1].
The endovascular approach to treat thoracic aortic aneurysms was initially demonstrated by Dake et al. in
1994. They presented the first successful deployment of a stent graft as a thoracic endovascular aortic repair
(TEVAR) . In 1999, two case series showed successful endovascular treatments of complicated acute type B
[7]
dissections with endograft coverage of the proximal entry tear . Ultimately, in 2005, the United States
[8,9]
Food and Drug Administration (US FDA) approved the first endograft device for human implantation
following the completion of the Gore TAG pivotal trial .
[10]
In 2001, Chuter et al. presented a modular stent-graft system with small branches to pursue the
endovascular treatment of TAAAs with preservation of side branches perfusion, offering a less invasive
[11]
approach . Even though open surgical repair has been considered the preferred approach providing
definitive and reliable repair for TAAA, endovascular repair has evolved consistently, presenting a variety of
techniques and devices to achieve the treatment of many different aortic pathologies that lead to aneurysm
degeneration [10,12-14] . Currently, patient-specific custom-made devices with fenestrations and branches have
been developed to match with the anatomy of a specific patient, while standardized off-the-shelf branched
devices provide an immediately available solution suitable to common anatomies [15-20] [Figure 2].

PATIENT SELECTION
Clinical and anatomical factors
Generally, TAAAs are initially asymptomatic and the disease’s natural history is progression with an
increase in diameter, followed by rupture or dissection . In addition, embolization of thrombus associated
[21]
with the aneurysm wall, or of atheromatous debris, may cause malperfusion syndrome, including
mesenteric ischemia, renal ischemia, or peripheral limb ischemia. Erosion of the aneurysm into abutting
structures may also occur . Aortic dissection can also further degenerate into aortic aneurysms, and post-
[22]
dissection aneurysms usually comprise the thoracoabdominal aorta, thereby requiring thoracoabdominal
repair. A significant number of patients with acute type B dissections will develop chronic post-dissection
aneurysms and need definitive treatment at some stage, either open or with fenestrated/branched stent
grafts. Key characteristics in this event are the narrow true lumen of the aorta and visceral branches arising
from the false lumen, which applies particularly to either of the renal arteries. In these circumstances,
several techniques have been used to cross the thick chronic dissection flap, such as wires with tips that can
be stiffened, the back of a wire, a wire with the support of a guiding sheath, or even a needle to perforate the
[23]
dissection flap .

The diameter of the aorta in the thoracoabdominal segment is considered the strongest predictor of adverse
[24]
events, such as rupture, dissection, and mortality in asymptomatic patients . Elective repair is typically
indicated for aortic diameter greater than 6 cm as the limit that justifies surgical risk compared with rupture
risk. Aneurysms with a diameter between 5 and 6 cm have a 6.5% annual risk of rupture, dissection, or
death. Those greater than 6 cm in diameter have an annual risk as high as 14.1% . The vast majority (93%)
[25]
of ruptures occur with diameters over 5 cm .
[21]