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Page 2 of 7 Harky et al. Vessel Plus 2018;2:8 I http://dx.doi.org/10.20517/2574-1209.2018.12

rupture or dissection, however the clinical emergency occurs when such aneurysms rupture. Although it
is a rare pathology, ruptured descending thoracic aortic aneurysm (rDTAA) carries high mortality and
[1]
morbidity rates with the majority of patients dying prior to arrival to hospital . The incidence of rupture is
estimated to be 5 in 100,000 of population.

Just over a decade ago, the gold standard management of rDTAA was open repair (OR) requiring
thoracotomy, aortic cross-clamping, aneurysm resection and replacement with an interposition of a
[2-4]
prosthetic graft and cardiopulmonary bypass . However, ORs were associated with high perioperative
[5]
mortality and neurological adverse events ; nevertheless with advancement in clinical practice and
evolving minimal access surgical interventions, the role of endovascular repair in such emergencies
has been explored. Thoracic endovascular aortic repair (TEVAR) has appealing qualities including a
minimally invasive procedure with rapid deployment with decreased operative time and decreased blood
[3]
loss . However, this approach is subject to anatomical and logistical limitations, including anatomical
requirements and variations, the quality of the landing zones, ease of iliac access, availability of the wide
[4]
range of stent graft sizes in an emergency setting and available expertise on site . The major benefits of
endovascular repair reported are lower mortality and morbidity rates associated with such a complex
[5]
procedure . The advantage of TEVAR was not only limited to such perioperative outcomes but TEVAR
was also used in patients who were not surgical candidates, which has resulted in an alternate management
[5]
option as opposed to conservative management in those patients with almost 100% mortality rates .
Despite TEVAR being an attractive alternative option for OR, it still remains a high-risk procedure. The
current literature has many limitations in that the majority of evidence comes from case series and there is
a lack of appropriate randomized controlled trials or long term comparative data that confirms the accuracy
[6-8]
of the data and thus globalization of the results . Therefore, the aim of this paper is to review current
literature and the evidence behind using TEVAR in the emergency setting of rDTAA and comparing the
clinical outcomes with OR in such cohort of patients.

EVIDENCES BEHIND TEVAR IN rDTAA
The use of endovascular repair goes back to as early as 1991, when first performed on an abdominal aortic
[9]
aneurysm . Since then, the technology has evolved with advancement in using endovascular repair for
aortic aneurysms repair. Most of the patients who experience rDTAA do not survive to present to hospital.
Hence why of those that do, open repair remains a strong choice for managing such patients. Yet, open
repair is associated with significantly higher rates of mortality (ranging 14%-45% in specialized centers) and
morbidity peri- and post-operatively [10-13] .

[14]
Currently, TEVAR is the standard management plan for elective cases of DTAA , however the evidences
[7]
behind using TEVAR in the emergency setting are scarce and limited . There are however several published
reports from international centers about the clinical outcomes for the use of TEVAR in emergency situations
for rDTAA [2,6-8,15] , but most of these are limited to a relatively small number of cases and are observational
studies. These studies have been summarized in Table 1.

[7]
A study by Jonker et al. analysed 87 patients that underwent emergency TEVAR for rDTAA between
2002 and 2009. The majority of the cases (> 90%) were in critical condition and immediate intervention
was required. Forty percent of the patients were haemodynamically unstable and 22% were in shock. In
their study, they have noted a 30-day mortality rate of 18.4%, whilst the rate of stroke and neurological
complications were 8% in both. Eighteen percent of the patients were diagnosed with an endoleak within
30 days of the procedure. It is important to note that the presence of shock and haemothorax at the time of
admission were the two contributing factors for increased mortality rates in these groups of patients. The
[16]
same group published their data of 161 patients, of which 92 patients were treated with OR and 69 with