Long-term Outcomes of Endovascular Repair for Blunt Thoracic Aortic Injury: A 10 Year Multi-center Experience

OBJECTIVE

This study aimed to assess the long-term outcomes in patients treated by thoracic endovascular aortic repair (TEVAR) for blunt thoracic aortic injuries (BTAI).

MATERIALS AND METHODS

From January 2010 to December 2019, this retrospective observational study was conducted at 3 centers, involving 62 consecutive BTAI patients who underwent TEVAR. Computed tomography angiography scans were planned to be conducted at 6 months post-procedure, and annually thereafter.

RESULTS

Technical success was achieved in all 62 procedures (100%), which included cases of dissection (n=35, 56.45%), pseudoaneurysm (n=20, 32.26%), and rupture (n=7, 11.29%). Mean injury severity score was 31.66±8.30. A total of 21 supra-arch branches were revascularized by chimney technique, with 12 cases involving the left subclavian artery (LSA) and 9 cases involving the left common carotid artery. In addition, 11 LSAs were covered during the procedure. The in-hospital mortality rate was 1.61% (n=1). The mean follow-up time was 86.82±30.58 months. The all-cause follow-up mortality rate was 3.28% (n=2). Stenosis or occlusion of 3 supra-arch branches (4.92%) was identified at follow-up, with 2 cases (3.28%) requiring re-intervention. No spinal cord ischemia, endoleak, or migration was observed.

CONCLUSIONS

Despite only including patients with long-term follow-up, this study confirms the long-term safety and effectiveness of TEVAR for BTAI. For young BTAI patients, as the thoracic aorta increases with age, longer follow-up is needed to observe the potential mismatch between the endograft and the aorta.

CLINICAL IMPACT

This study confirms the long-term safety and effectiveness of endovascular treatment for blunt thoracic aortic injury (BTAI). For young BTAI patients, as the thoracic aorta increases with age, longer follow-up is needed to observe the potential mismatch between the endograft and the aorta. Through a remarkably extended follow-up period (86.82±30.58 months) conducted at multiple centers in China, this study confirms the long-term safety and effectiveness of endovascular treatment for BTAI.

A Systematic Review on Thoracic Endovascular Repair Outcomes in Blunt Thoracic Aortic Injuries

PURPOSE

Blunt thoracic aortic injury (BTAI) represents a potentially life-threatening condition and thoracic endovascular aortic repair (TEVAR) is recommended as the first-line treatment (Class I level of evidence C) by the current guidelines. The aim of this systematic review was to determine the perioperative and mid-term follow-up outcomes of patients with BTAI treated with TEVAR.

MATERIALS AND METHODS

We reviewed the English literature published between 2000 and 2022, via Ovid, using MEDLINE, EMBASE, and CENTRAL databases, until July 30, 2022. Observational studies and case series, with ≥5 patients, reporting on the perioperative and follow-up outcomes of patients who underwent TEVAR for BTAI were included. The Newcastle-Ottawa Scale was used to assess the risk of bias. Primary outcomes were technical success and 30-day mortality, cerebrovascular morbidity. Secondary outcomes were mortality and re-interventions during the mid-term follow-up.

RESULTS

From 5201 articles identified by the literature search, 35 eligible studies were included in this review. All studies had a retrospective study design. In total, 991 patients were included. The mean age was 34.5±16.5 years (range=16-89 years). Technical success was 98.0% (odds ratio [OR], 95% confidence interval [CI]=0.98, 0.99, p<0.001, I2=0%). Mortality at 30 days was 5.0% (OR, 95% CI=0.03, 0.06, p<0.001, I2=5.56%). Spinal cord ischemia occurred in 1.0% (OR, 95% CI=0.01, 0.02, p<0.001, I2=0%) and stroke rate was 2.0% (OR, 95% CI=0.01, 0.02, p<0.001, I2=0%). The available follow-up was estimated at 29 months (range=3-119 months) with mortality rate at 2.0% (OR, 95% CI=0.01, 0.02, p<0.001, I2=0%) and re-intervention rate at 1.0% (OR, 95% CI=0.01, 0.02, p<0.001, I2=10.5%).

CONCLUSION

Thoracic endovascular aortic repair showed high technical success and low early cerebrovascular morbidity and mortality rates. In the mid-term follow-up, the estimated mortality and re-intervention rates were also low. Furthermore, higher quality prospective studies are needed.

CLINICAL IMPACT

Thoracic endovascular aortic repair (TEVAR) is recommended as the first line treatement in patients with blunt thoracic aortic injuries (BTAI). This systematic review of 35 retrospective studies and 991 patients showed high technical success (98.0%) with an associated 30-day mortality at 5.0% and low spinal cord ischemia (1%) and stroke rates (2.0%). Mid-term mortality and re-intervention rates reassure the effectiveness of TEVAR in BTAI cases.

Arterial Stiffness and Aortic Aneurysmal Disease - A Narrative Review

It has been documented that large-artery stiffness is independently associated with increased cardiovascular risk and may potentially lead to heart and kidney failure and cerebrovascular disease. A systematic review of studies investigating changes in arterial stiffness in patients undergoing endovascular repair of aortic disease was conducted. In addition, a review of the available literature was performed, analyzing findings from studies using the cardio-ankle vascular index (CAVI) as a marker of arterial stiffness. Overall, 26 studies were included in the present analysis. Our research revealed a high heterogeneity of included studies regarding the techniques used to assess the aortic stiffness. Aortic stiffness was assessed by pulse wave velocity (PWV), elastic modulus (Ep), and augmentation index (AI). Currently a few studies exist investigating the role of CAVI in patients having an aortic aneurysm or undergoing endovascular aortic repair. The majority of studies showed that the treatment of an abdominal aortic aneurysm (AAA) either with open repair (OR) or endovascular aortic repair (EVAR) reduces aortic compliance significantly. Whether EVAR reconstruction might contribute a higher effect on arterial stiffness compared to OR needs further focused research. An increase of arterial stiffness was uniformly observed in studies investigating patients following thoracic endovascular aortic repair (TEVAR), and the effect was more pronounced in young patients. The effects of increased arterial stiffness after EVAR and TEVAR on the heart and the central hemodynamic, and an eventual effect on cardiac systolic function, need to be further investigated and evaluated in large studies and special groups of patients.

Echocardiographic Changes in Cardiac Function After Thoracic Endovascular Aortic Repair: A Systematic Review and Meta-Analysis

BACKGROUND

Evidence suggests thoracic stent grafts increase the aortic stiffness postimplantation. Our objective was to examine the effect of thoracic aortic stenting on heart function, as demonstrated with echocardiography.

METHODS

We considered nonrandomized studies examining echocardiographic parameters (left ventricle ejection fraction (LVEF), left ventricle end-diastolic (LVED) and end-systolic diameter (LVESD), posterior wall thickness (LVPWT), interventricular septal thickness (IVST), mass, and mass index) pre and poststent graft implantation in patients with thoracic aortic diseases (aneurysm, dissection, and blunt injury). MEDLINE and CENTRAL were searched (up to March 2021) for eligible studies. The National Institutes of Health Quality Assessment Tool was used for risk of bias assessment. Echocardiographic data pre and postimplantation were compared using the pooled standardized mean difference (SMD) and 95% confidence interval (CI).

RESULTS

Four studies were included in the meta-analysis. Three of the studies were judged to be "good" quality and one "fair". Nonsignificant differences pre and postimplantation were found for ejection fraction (SMD = -0.53, 95% CI = -1.8 to 0.728, P = 0.406), IVST (SMD = -0.79, 95%, CI = -3.25 to 1.66, P = 0.52), EDD (SMD = -0.10, 95% CI = -0.48 to 0.28, P = 0.60), ESD (SMD = -0.66, 95% CI = -2.35 to 1.02, P = 0.44), and PWT (SMD = -2.20, 95% CI = -5.89 to 1.47, P = 0.24). A trend toward an increase in mass postimplantation was found (SMD = 0.28, 95%, CI = -0.03 to 0.60, P = 0.08), but there was no significant difference in mass index (SMD = 0, 95%, CI = -0.195 to 0.195, P = 1).

CONCLUSIONS

Thoracic aortic stenting does not appear to significantly impact cardiac physiology as indicated by echocardiographic parameters.

Global and local stiffening of ex vivo-perfused stented human thoracic aortas: A mock circulation study

The effects of thoracic endovascular repair (TEVAR) on the biomechanical properties of aortic tissue have not been adequately studied. Understanding these features is important for the management of endograft-triggered complications of a biomechanical nature. This study aims to examine how stent-graft implantation affects the elastomechanical behavior of the aorta. Non-pathological human thoracic aortas (n=10) were subjected to long-standing perfusion (8h) within a mock circulation loop under physiological conditions. To quantify compliance and its mismatch in the test periods without and with a stent, the aortic pressure and the proximal cyclic circumferential displacement were measured. After perfusion, biaxial tension tests (stress-stretch) were carried out to examine the stiffness profiles between non-stented and stented tissue, followed by a histological assessment. Experimental evidence shows: (i) a significant reduction in aortic distensibility after TEVAR, indicating aortic stiffening and compliance mismatch, (ii) a stiffer behavior of the stented samples compared to the non-stented samples with an earlier entry into the nonlinear part of the stress-stretch curve and (iii) strut-induced histological remodeling of the aortic wall. The biomechanical and histological comparison of the non-stented and stented aortas provides new insights into the interaction between the stent-graft and the aortic wall. The knowledge gained could refine the stent-graft design to minimize the stent-induced impacts on the aortic wall and the resulting complications. STATEMENT OF SIGNIFICANCE: Stent-related cardiovascular complications occur the moment the stent-graft expands on the human aortic wall. Clinicians base their diagnosis on the anatomical morphology of CT scans while neglecting the endograft-triggered biomechanical events that compromise aortic compliance and wall mechanotransduction. Experimental replication of endovascular repair in cadaver aortas within a mock circulation loop may have a catalytic effect on biomechanical and histological findings without an ethical barrier. Demonstrating interactions between the stent and the wall can help clinicians make a broader diagnosis such as ECG-triggered oversizing and stent-graft characteristics based on patient-specific anatomical location and age. In addition, the results can be used to optimize towards more aortophilic stent grafts.

Pulse Wave Velocity for Risk Stratification of Patients with Aortic Aneurysm

Background: Patients with an aortic aneurysm are at high cardiovascular risk. Pulse wave velocity (PWV) is used as a parameter for risk stratification but may be affected by aortic disease (AoD). This study aimed to investigate the dependence of PWV on treated or untreated AoD and to identify modifiable factors of PWV. Methods: The measurement of PWV with the Mobil-O-Graph was performed fully automatically in a collective of 381 patients (75.6% male and 24.4% female). Of all patients, 53.8% had nonaortic atherosclerotic vascular disease (AVD), 28.9% had treated AoD, and 17.3% had untreated AoD. Results: There was a statistically significant effect of age (R2 = 0.838) and current systolic blood pressure (SBP) on PWV (page corrected < 0.05). After correction for age, no statistically significant difference was found between the PWV of men and women, patients with different body weights or degrees of chronic kidney disease, diabetics and nondiabetics, and smokers and nonsmokers. Comparison between patients with nonaortic AVD and treated or untreated AoD revealed no statistically significant differences (PWVnonaortic AVD 10.0 ± 1.8 m/s, PWVtreated AoD 10.0 ± 1.5 m/s, PWVuntreated AoD 9.8 ± 1.6 m/s; page corrected > 0.05). Conclusions: PWV determined with the Mobil-O-Graph correlated with age and current SBP. Neither aortic disease versus nonaortic AVD, its treatment, nor other cardiovascular risk factors had a significant effect on PWV. Successful blood pressure control is crucial to avoid high PWV and thus an increase in cardiovascular events.

Geometric, Biomechanic and Haemodynamic Aortic Abnormalities Assessed by 4D Flow Cardiovascular Magnetic Resonance in Patients Treated by TEVAR Following Blunt Traumatic Thoracic Aortic Injury

OBJECTIVE

Thoracic endovascular aortic repair (TEVAR) is widely used for the treatment of patients with blunt traumatic thoracic aortic injury (BTAI). However, aortic haemodynamic and biomechanical implications of this intervention are poorly investigated. This study aimed to assess whether patients treated by TEVAR following BTAI have thoracic aortic abnormalities in geometry, stiffness, and haemodynamics.

METHODS

Patients with BTAI treated by TEVAR at Vall d'Hebron Hospital between 1999 and 2019 were compared with propensity score matched healthy volunteers (HVs). All subjects underwent cardiovascular magnetic resonance (CMR) comprising a 4D flow CMR sequence. Spatially resolved aortic diameter, length, volume, and curvature were assessed. Pulse wave velocity, distensibility, and longitudinal strain (all measurements of aortic stiffness) were determined regionally. Moreover, advanced haemodynamic descriptors were quantified: systolic flow reversal ratio (SFRR), quantifying backward flow during systole, and in plane rotational flow (IRF), measuring in plane strength of helical flow.

RESULTS

Twenty-six BTAI patients treated by TEVAR were included and matched with 26 HVs. They did not differ in terms of age, sex, and body surface area. Patients with TEVAR had a larger and longer ascending aorta (AAo) and marked abnormalities in local curvature. Aortic stiffness was greater in the aortic segments proximal and distal to TEVAR compared with controls. Moreover, TEVAR patients presented strongly altered flow dynamics compared with controls: a reduced IRF from the distal AAo to the proximal descending aorta and an increased SFRR in the whole thoracic aorta. These differences persisted adjusting for cardiovascular risk factors and were independent of time elapsed since TEVAR implantation.

CONCLUSION

At long term follow up, previously healthy patients who underwent TEVAR implantation following BTAI had increased diameter, length and volume of the ascending aorta, and increased aortic stiffness and abnormal flow patterns in the whole thoracic aorta compared with matched controls. Further studies should address whether these alterations have clinical implications.

Atherosclerotic Burden and Arterial Stiffness are Not Increased in Patients with Milder Forms of Primary Aldosteronism Compared to Patients with Essential Hypertension

Patients with primary aldosteronism (PA) are at increased cardiovascular risk, compared to patients with essential hypertension (EH). Cardiovascular damage could depend on PA phenotype, potentially being lower in milder forms of PA. Our aim was to assess atherosclerotic burden and arterial stiffness in 88 prospectively recruited patients, including 44 patients with mild PA and EH respectively. All patients underwent a structured study program, including measurements of ankle-brachial index, oscillometric measurement of central pulse wave velocity (cPWV) and vascular ultrasound examination of the supraaortic arteries, the abdominal aorta, and the femoropopliteal arteries. A plaque score was calculated to estimate atherosclerotic burden for each patient. This is a prospective case-control study set at a tertiary care hospital. Patients with PA and EH matched well for age, gender, blood pressure, BMI, and cardiovascular risk factors such as diabetes mellitus and smoking status. Common carotid intima-media thickness (0.77 vs. 0.75 mm; p=0.997) and cPWV (7.2 vs. 7.1 m/s; p=0.372) were comparable between patients with PA and EH. The atherosclerotic burden, as expressed by the plaque score, did not differ between the two groups (p=0.159). However, after initiation of treatment cPWV was significantly decreased in patients with PA (p=0.017). This study shows that subclinical atherosclerotic burden and arterial stiffness in patients with milder forms of PA is comparable to patients with EH. Nevertheless, specific treatment for PA significantly improved cPWV, which argues for a more liberal use of mineralocorticoid receptor antagonists in patients with arterial hypertension.

Thoracic endovascular aortic repair for traumatic aortic injuries: insight from literature and practical recommendations

INTRODUCTION

Thoracic endovascular aortic repair (TEVAR) for treatment of blunt traumatic aortic injuries (BTAIs) is nowadays the gold standard technique in adult patients, replacing gradually the use of open repair (OR). Although randomized controlled trials will never be performed comparing TEVAR to OR for BTAIs management, trauma and vascular societies guidelines today primarily recommend the former for BTAI patients with a suitable anatomy. The aim of this review was to describe past and recent data published in literature regarding pros and cons of TEVAR treatment in BTAI, and to analyze some debated issues and future perspectives.

EVIDENCE ACQUISITION

Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and Scale for the Assessment of Narrative Review Articles (SANRA) were used to obtain and describe selected articles on TEVAR in BTAI.

EVIDENCE SYNTHESIS

Young (<50 years) men were the most operated population. The use of TEVAR increased over the years, with a progressive reduction in mortality and overall postoperative complication rates when compared with OR. Lack of information remains about the percentage of urgent cases.

CONCLUSIONS

TEVAR is considered nowadays the treatment of choice in BTAI patients. In case of aortic rupture (grade IV) the treatment is mandatory, while intimal tear (grade I) and intramural hematoma (grade II) can be safely managed with no operative management (NOM). Debate is still ongoing on grade III (pseudoaneurysms). Unfortunately, several aspects remain not yet clarified, including disease classification, type and grade to treat, timing (urgent versus elective), priority of vascular injuries in polytrauma patients, and TEVAR use in pediatrics and young patients.