The Endovascular Surgery Chapter (CCEV) of the Spanish Society of Angiology and Vascular Surgery (Sociedad Española de Angiología y Cirugía Vascular [SEACV]) invited all the Departments of Angiology and Vascular Surgery in Spain to participate in a multicenter retrospective registry of patients with descending thoracic aorta disease treated on an emergency or elective basis using TEVAR techniques. Eleven Departments agreed to participate in the compilation of data on patients operated upon in the period 2012–2016, following approval from the local Ethics Committees.

A total of 287 patients were included in the national registry (Regis-TEVAR), divided into two groups according to whether surgery was elective (surgery that could be postponed at least 24 h) or constituted emergency or emergent surgery (i.e., surgery performed within less than 24 h). Of the 287 patients, 135 underwent emergency surgery and were selected as the study group. The following indications were included: RTAA, TTA and TBADc, as detailed in Appendix A (Table 1), available only as Supplementary material in the electronic version (inclusion and exclusion criteria). The main aim of our study was to conduct a descriptive analysis of the technical characteristics and outcomes of the patients subjected to emergency surgery, with the 152 patients subjected to elective surgery being used as a reference for the comparison of concrete aspects versus emergency surgery.

From each patient we collected preoperative information, specific data according to the indication of repair, intraoperative data and postoperative data, comprising a total of 56 descriptive variables referred to the technique and outcome (Appendix A [Table 2], available only as Supplementary material in the electronic version). These variables had been previously validated by the VASCUNET (https://vascunet.org), the Working Committee of the European Society of Surgery Vascular (ESVS) created in 1997, with the purpose of collecting information from over 15 vascular registries in Europe, Australia and New Zealand.

We specifically analyzed the following for each disease condition: type of complication for emergency repair in the dissections, aortic diameter in the ruptured aneurysms and the grade of thoracic aortic traumatism (type I, type II, type III or type IV) according to the classification of Azizzadeh et al.9

With regard to the surgical technique, we analyzed the number of stents placed and the proximal and distal anchoring zones according to the classification of Fillinger et al.10 (Figs. 1 and 2). Consideration was made of the type of endoprosthesis employed (Valiant, Zenith Alfa, Captivia, TAG, etc.), together with the percentage of branches of the aortic arch revascularized or covered during the procedure, as well as specifically which of the branches (left subclavian artery, left carotid artery, celiac trunk, superior mesenteric artery or renal arteries), with a view to assessing their association to possible postoperative complications. These clinical complications were: infection, postoperative bleeding requiring repeat surgery, postoperative paraplegia, cerebrovascular accident (CVA), acute coronary events, renal failure with a need for dialysis, respiratory failure and intestinal ischemia. We also analyzed survival at 30 days and over the 5-year follow-up period. We took into account the percentage of reinterventions, i.e., any type of endovascular procedure (extensions, embolizations, repeat angioplasty, etc.), with the purpose of correcting technical failures in the first 30 days.

Figure 1.

Classification of the proximal anchoring zones of the endoprosthesis in the descending thoracic aorta.

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Figure 2.

Classification of the distal anchoring zones of the endoprosthesis in the descending thoracic aorta.

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Continuous variables were reported as the mean ± standard deviation (SD). Categorical data were expressed as percentages. Patient survival – both perioperative and after up to 5 years – was assessed based on Kaplan–Meier analysis. Survival rates were compared using the log-rank test and Gehan test. Statistical significance was considered for p < 0.05. The SPSS version 24 statistical package was used throughout.

A total of 287 patients were consecutively included, covering the period 2012–2016: 152 subjected to elective surgery and 135 to emergency surgery. Of the 135 emergency procedures, 111 corresponded to males (82.2%) and 24 to females (17.8%), from 11 Departments of Angiology and Vascular Surgery throughout Spain. The number of patients included per center ranged from 8 to 78 cases. The mean age was 60.4 ± 16.3 years among the emergency surgery cases (this being younger than the patients subjected to elective surgery, with 67.4 ± 11.15 years). A total of 12.6% of the patients presented diabetes mellitus, 38.5% suffered ischemic heart disease, and 22.2% presented chronic obstructive pulmonary disease (COPD). The main cardiovascular risk factors are reported in Table 1. With regard to risk status, 42.9% of the patients subjected to emergency surgery (58 cases) presented a preoperative ASA (American Society of Anesthesiologists) score of V, versus only 2% of the patients subjected to elective surgery.

The most frequent indication of emergency TEVAR was complicated type B dissections, with 54 cases (40%), followed by RTAA with 43 cases (31.9%), TTA with 32 cases (23.7%) and other less frequent conditions such as intramural hematomas and complicated penetrating ulcers (4.4%) (Table 2). The mean diameter of the thoracic aorta in the 43 cases of ruptured aneurysms was 67.67 ± 22.4 mm — this being greater than the aortic diameter in the cases of elective repair (61.31 ± 16.05 mm).

Of the 54 cases with TBADc, 31.5% initially manifested in the form of visceral ischemia, 22.2% as aortic rupture and 18.5% in the form of pain refractory to treatment, obliging emergency repair. With regard to TTA (32 cases), a total of 56.3% were lesions classified as type III or pseudoaneurysms, while 11 (34.4%) were classified as type IV (aortic rupture) according to the classification of Azizzadeh et al.9

The present study did not include data such as the type of femoral access (percutaneous versus open), the use of ultrasound (transesophageal ultrasound or intravascular ultrasound [IVUS]), lumbar cerebrospinal fluid (CSF) drainage, etc. We analyzed the type of endoprosthesis used (Gore TAG, Relay, Valiant, etc.) and the number of stents placed — no statistically significant differences being observed. Anchoring of the endoprosthesis was proximal to the left subclavian artery (LSA), specifically in zones 0 and 1 (Fig. 1) in only 2.2% of the cases, representing coverage of three left carotid arteries, all revascularized in the same surgical step. In turn, 41.5% of the TEVARs were anchored in zone 2, representing the coverage of 58 LSAs (43% of the total), of which only 6 were revascularized (4.4% of the cases) — this being far lower than the 30.9% of LSAs revascularized in the cases of elective repair (Table 3). No statistically significant differences were recorded in the paraplegia or CVA rates between the group of patients with covered and revascularized LSA and the cases in which such revascularization was not made. Distal anchoring (Fig. 2) was in zone 5 in 48.1% of the cases and in zone 4 in 38.5% of the cases — this representing a total of 86.6% of the distal anchorings above the celiac trunk without the covering of visceral branches. In turn, 8.9% of the endoprostheses were positioned in zones 6, 7 and 8, representing the covering of four celiac trunks (25% revascularized, when associating disease in the other two axes), two superior mesenteric arteries (100% revascularized), and four renal arteries (100% revascularized).

The global mortality rate among the cases of emergency TEVAR was 18.5% (25 of the 135 patients died within the first 30 days after the operation) versus 5.3% in the cases of elective surgery (8/152) — though the difference was not statistically significant: 20.4% in TBADc, 27.9% in RTAA and 6.3% in TTA.

Survival was analyzed using the Kaplan–Meyer method for a maximum follow-up period of 60 months. A total of 67 ± 6% were still alive at the end of follow-up. The actuarial survival rate according to disease condition was 76% in the cases of TBADc, 42% in RTAA and 83% in TTA at 5 years (Fig. 3). The comparison of the survival rates according to the type of disease revealed statistically significant differences (Gehan test; p < 0.05).

Figure 3.

Comparison of the 5-year survival rates according to disease condition.

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Reinterventions during admission were required in 12 patients (9%), being more frequent in dissections (13%) than in the rest of the disease conditions. Sixty percent of these reinterventions were due to technical failures related with the devices, such as type I endoleakage, LSA occlusion failure, etc.

The incidence of postoperative bleeding was 5.2%, and was higher in the case of ruptured thoracic aneurysms (11.6%) (Table 3). The incidence of infection in any location was 13.3% (18.6% in RTAA). Most of these infections were respiratory processes (11.1%), possibly due to the associated lung concussion and ventilation difficulties. In turn, the postoperative CVA rate was 5.2%, and was mainly associated with dissections (9.3%) — the percentage being considerably greater than the 1.3% in the cases subjected to elective surgery. The incidence of postoperative paraplegia was 5.9% (the highest figure again corresponding to dissections with 9.3%, versus 2.3% in RTAA and 6.3% in TTA). Coronary events were observed in 2.2% of the operated patients, and 12.6% required postoperative hemofiltration (18.5% in the case of dissections). Mesenteric ischemia was recorded in 5.9% of the cases, and was likewise more common among the dissections (11.1%). Of the patients with thoracic trauma, one-third suffered postoperative respiratory failure.

Emergency lesions of the thoracic aorta, including TBADc, RTAA and TTA, are a management challenge. The emergency repair of these conditions is associated with high morbidity–mortality, and despite the advances in surgical techniques and perioperative management, this type of surgery continues to pose a very high risk.11 Although initially developed for the treatment of abdominal aneurysms, endovascular techniques have become the option of choice in emergency situations, since the morbidity–mortality reported in the literature is favorable to these techniques versus classical OS.12 A recent meta-analysis including 14,580 patients (10,672 subjected to OS and 3908 to endovascular techniques) has reported better perioperative outcomes with TEVAR, despite the fact that the patients presented greater surgical risk.13 However, there is still not enough evidence comparing the outcomes at 5 and 10 years between the two treatment strategies. Specifically, in the case of RTAA, the existing literature evidences an in-hospital mortality rate of between 24.6% and 45.6% for OS, while in the case of TEVAR the figure varies between 17.4% and 30%.14 In our series, the global mortality rate was 18.5%, though in the specific case of the mentioned disease condition the figure was 27.9% — the highest percentage of all three indications. A limitation of our study is the fact that we have not been able to compare our series with patients subjected to OS, since this was not the purpose of our research. The recent European guide on endovascular treatment of the descending thoracic aorta (Management of Descending Thoracic Aorta Diseases: Clinical Practice Guidelines of the European Society for Vascular Surgery [CPG-ESVS])14 recommends endovascular repair as the first option in cases of RTAA, provided the anatomical characteristics are suitable (recommendation 23: class I, level of evidence B).

In the case of TBADc, the aim of emergency repair in both OS and TEVAR is not only to cover the tear in the intima of the aorta but also to reduce the pressure in the false lumen, and thus improve perfusion of vital organs such as the intestine and kidneys. In our series, 31.5% of the cases of TBAD initially presented mesenteric ischemia as the main preoperative treatment indication. Although the outcomes of OS over TBADc have improved in recent decades, its complication rates remain high, and the mortality rate is between 25%–50%,16 due to the long surgery times and profuse bleeding. The CPG-ESVS considers OS in TBADc to be an alternative to endovascular treatment when the latter has failed or is contraindicated (recommendation 19: class IIa, level of evidence C). At present there are three meta-analyses with short- and middle-term outcomes referred to patients with TBADc and TEVAR, describing mortality rates between 2.6% and 9.8% (somewhat higher in our series: 20.4%) and a neurological complications rate of between 0.6% and 3.1%.17–19 The presence of visceral complications due to hypoperfusion is a predictor of greater mortality20; in this regard, one of the main advantages of TEVAR over OS is that is allows faster patient stabilization, with lesser invasiveness, and thus reduces the poor perfusion syndrome associated to TBADc.21 In our series, 6/8 cases of postoperative mesenteric ischemia were recorded in TBADc (11.1%), with a mortality rate of 16.7% in these patients.

In the case of thoracic trauma, in the same way as in TBADc and RTAA, the conventional treatment of thoracic damage always involved open repair and the placement of a stent. The mortality rate of OS in TTA has been very high (24%–42%), due to the fact that trauma implies lung contusion, solid organ damage, head injuries, the need for anticoagulation for surgery, etc. Because of this, there has been great interest in developing a less invasive technique for TTA, and TEVAR has been essential from the beginning in this respect — demonstrating a decrease in mortality rate to 9.7% (6.3% in our series).22,23 The GPC-ESVS recommends TEVAR in these patients as first treatment option (recommendation 29: class I, level of evidence C).

Having established the advantages of TEVAR versus OS in diseases of the descending thoracic aorta (DTA), important differences in outcome are observed according to whether the technique is performed on an emergency or elective basis. In our registry, the mortality rate with the endoprosthesis was 5.3% in the case of elective repair and 18.5% in emergency endovascular repair — though the difference was not statistically significant. There is information in our series that may explain these differences, such as the fact that the preoperative ASA score in the emergency cases was V in 42.9% of the cases, while only 2% of the elective cases presented this same score. It has also been established that an older age of the patients and a greater diameter of the thoracic aorta aneurysm (TAA) are predictors of greater mortality.24 Both of these circumstances concur in our emergency TEVAR group versus the elective group (Table 5).

In the case of the traumatisms in our series, 56.3% were of type III (pseudoaneurysms of the thoracic aorta) and 34.4% of type IV (complete transection). This is an indicator of the greater severity of the emergency cases. In elective TEVAR, these percentages were lower and the lesions were less severe (type I and type II). An extensive literature review25 including 139 studies and 7768 patients suggests that aortic repair in TTA should be postponed if there are other severe lesions that require stabilization — though if the aortic lesion is severe, repair should be carried out on an emergency basis (recommendation 27: class I, level of evidence C).15,26