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Katz et al. Vessel Plus 2023;7:1 https://dx.doi.org/10.20517/2574-1209.2022.52 Page 13 of 16

UNIQUE CONSIDERATIONS FOR ENDOVASCULAR REPAIR OF THE DESCENDING
THORACIC AORTA
The introduction of endovascular stent-grafts in 2005 has led to widespread adoption of thoracic
endovascular aortic repair (TEVAR) for DTAs. As a less-invasive procedure than open repair, TEVAR
significantly reduces the physiological insult to the patient, reduces the early mortality rate, and is associated
with a lower risk for many of the complications associated with open repair, such as paraplegia, renal and
[53]
respiratory failure, the need for transfusions, and longer hospital stays, among others . For example, most
patients undergoing TEVAR are extubated on the operating room table. Nonetheless, TEVAR raises several
[54]
unique considerations in perioperative care .

Postimplantation syndrome
Postimplantation syndrome is characterized by a systemic inflammatory response, with elevation of
inflammatory cytokines and other inflammation markers. Sympathetic pleural effusions may also be
[55]
present. The reported incidence of postimplantation syndrome varies widely (from 13% to 60%) . The
syndrome is thought to be caused by local inflammatory cascade in the endothelium of the excluded aorta.
Postimplantation syndrome does not require antimicrobial therapy (although differentiation from infection
may be difficult). Treatment consists of aspirin and vigilant monitoring for other causes of systemic
inflammatory response.

Spinal cord management
In TEVAR, the spinal cord is managed much as it is for open repair. With short-segment coverage from the
endograft, the risk for spinal cord deficit is minimized. However, as the length of the TEVAR graft
increases, the risk for spinal cord ischemia increases . Cerebrospinal fluid drains are used less frequently in
[56]
TEVAR than in open surgery, and the data supporting the effectiveness of CSF drains in TEVAR are less
robust. We do selectively use CSF drains in patients undergoing long-segment coverage of the descending
thoracic aorta and those with previous abdominal aortic aneurysm repair. In patients undergoing TEVAR
without a CSF drain, any signs of spinal cord ischemia should prompt immediate drain placement and
management, as described for open repair.

Left subclavian artery management
Whether to revascularize the left subclavian artery or not is controversial, as there is debate as to whether
[57]
the risk for stroke is increased or decreased by subclavian revascularization . However, revascularization is
essential in certain patients, such as those with patent left internal mammary artery conduits or dominant
left vertebral arteries. In our practice, we revascularize the covered left subclavian artery in many, but not
all, patients. When in doubt, we perform the TEVAR and then obtain noninvasive measurements of the left
hand, including pulse oxygen waveform, photoplethysmography, and brachial-brachial index, before
deciding whether to proceed with revascularization. As in patients with steal syndrome after arteriovenous
fistula creation, mild symptoms can be managed using a structured exercise program.

CONCLUSION
The myriad conditions that complicate open TAAA and DTA repairs require specialized surgical expertise
and focused attention to perioperative care. Achieving successful outcomes after TAAA or DTA repair
requires knowledge about how to prevent complications and the ability to promptly recognize
complications to mitigate the extent of the injury. A multidisciplinary team approach and clear
communication are necessary to achieve these results.