Post-thoracic Endovascular Aortic Repair Research Articles

Assessment of the Aorto-Septal Angle Post-Thoracic Endovascular Aortic Repair through Segmentation and the Semi-Automatic Analysis of Cardiosynchronized Computed Tomography Angiography Images.

The aim of this study was to inviestigate cardiac and arterial remodelling before and after thoracic endovascular aortic repair (TEVAR) by measuring the Aorto-Septal Angle (AoSA) and the geometric characteristics of the aorta. Five patients were prospectively included. Pre- and post-operative cardio-CTA scans were used to create patient-specific 3D models to calculate the AoSA, defined by the intersection of the aortic and left ventricular axes. Additionally, geometric parameters and the inclination of the ascending aorta (AA) were measured. The results demonstrated a variation between pre- and post-operative AoSA in all patients, with an increase in the case of an aneurysmal disease from 112.36° ± 8.21° to 117.16° ± 9.65° (+4.1%, p = 0.041) and a decrease in the case of aortic dissection from 113.62° ± 0.96° to 107.83° ± 1.45° (-5.1%). Additionally, an increase in the length of both the outer and inner curvatures of the AA was observed from 102.21 ± 10.17 mm to 105.73 ± 11.2 mm (+ 3.33% p = 0.016) and from 55.55 ± 9.53 mm to 58.35 ± 9.96 mm (+4.8%, p = 0.04), respectively. This study introduced a new repeatable and reproducible method for assessing the AoSA using cardiac-CTA images. Thoracic stent deployment changes the AoSA, potentially impacting long-term left ventricle hemodynamics.

Patient-specific compliant simulation framework informed by 4DMRI-extracted pulse wave Velocity: Application post-TEVAR

We introduce a new computational framework that utilises Pulse Wave Velocity (PWV) extracted directly from 4D flow MRI (4DMRI) to inform patient-specific compliant computational fluid dynamics (CFD) simulations of a Type-B aortic dissection (TBAD), post-thoracic endovascular aortic repair (TEVAR). The thoracic aortic geometry, a 3D inlet velocity profile (IVP) and dynamic outlet boundary conditions are derived from 4DMRI and brachial pressure patient data. A moving boundary method (MBM) is applied to simulate aortic wall displacement. The aortic wall stiffness is estimated through two methods: one relying on area-based distensibility and the other utilising regional pulse wave velocity (RPWV) distensibility, further fine-tuned to align with in vivo values. Predicted pressures and outlet flow rates were within 2.3 % of target values. RPWV-based simulations were more accurate in replicating in vivo hemodynamics than the area-based ones. RPWVs were closely predicted in most regions, except the endograft. Systolic flow reversal ratios (SFRR) were accurately captured, while differences above 60 % in in-plane rotational flow (IRF) between the simulations were observed. Significant disparities in predicted wall shear stress (WSS)-based indices were observed between the two approaches, especially the endothelial cell activation potential (ECAP). At the isthmus, the RPWV-driven simulation indicated a mean ECAP>1.4 Pa-1 (critical threshold), indicating areas potentially prone to thrombosis, not captured by the area-based simulation.RPWV-driven simulation results agree well with 4DMRI measurements, validating the proposed pipeline and facilitating a comprehensive assessment of surgical decision-making scenarios and potential complications, such as thrombosis and aortic growth.

Risk prediction and prognostic analysis of post-implantation syndrome after thoracic endovascular aortic repair

This study aimed to establish a predictive model for the risk of post-thoracic endovascular aortic repair (TEVAR) post-implantation syndrome (PIS) in type B aortic dissection (TBAD) patients, assisting clinical physicians in early risk stratification and decision management for high-risk PIS patients. This study retrospectively analyzed the clinical data of 547 consecutive TBAD patients who underwent TEVAR treatment at our hospital. Feature variables were selected through LASSO regression and logistic regression analysis to construct a nomogram predictive model, and the model's performance was evaluated. The optimal cutoff value for the PIS risk nomogram score was calculated through receiver operating characteristic (ROC) curve analysis, further dividing patients into high-risk group (HRG) and low-risk group (LRG), and comparing the short to midterm postoperative outcomes between the two groups. In the end, a total of 158 cases (28.9%) experienced PIS. Through LASSO regression analysis and multivariable logistic regression analysis, variables including age, emergency surgery, operative time, contrast medium volume, and number of main prosthesis stents were selected to construct the nomogram predictive model. The model achieved an area under the curve (AUC) of 0.86 in the training set and 0.82 in the test set. Results from calibration curve, decision curve analysis (DCA) and clinical impact curve (CIC) demonstrated that the predictive model exhibited good performance and clinical utility. Furthermore, after comparing the postoperative outcomes of HRG and LRG patients, we found that the incidence of postoperative PIS significantly increased in HRG patients. The duration of ICU stay and mechanical assistance time was prolonged, and the incidence of postoperative type II entry flow and acute kidney injury (AKI) was higher. The risk of aortic-related adverse events (ARAEs) and major adverse events (MAEs) at the first and twelfth months of follow-up also significantly increased. However, there was no significant difference in the mortality rate during hospitalization. This study established a nomogram model for predicting the risk of PIS in patients with TBAD undergoing TEVAR. It serves as a practical tool to assist clinicians in early risk stratification and decision-making management for patients.

Thoracic Endovascular Aortic RepairAcutely Augments Left Ventricular Biomechanics in An Animal Model: A Mechanism for Postoperative Heart Failure and Hypertension

Thoracic aortic stent grafts are thought to decrease aortic compliance and may contribute to hypertension and heart failure after thoracic endovascular aortic repair (TEVAR). Left ventricular (LV) biomechanics immediately after TEVAR, however, have not been quantified. Pressure-volume (PV) loop analysis provides gold-standard LV functional information. The aim of this study is to use an LV PV loop catheter and analysis to characterize the LV biomechanics before and acutely after TEVAR. Anesthetized Yorkshire swine (N=6) were percutaneously instrumented with an LV PV loop catheter. A 20mm×10cm stent graft was deployed distal to the left subclavian via the femoral artery under fluoroscopy. Cardiac biomechanics were assessed before and after TEVAR. As a sensitivity analysis, inferior vena cava occlusion with PV loop assessment was performed pre and post-TEVAR in 1 animal to obtain preload and afterload-independent end-systolic and end-diastolic PV relationships (ESPVR and EDPVR). All animals underwent successful instrumentation and TEVAR. Post-TEVAR, all 6 animals had higher mean LV ESP (106 vs. 118mm Hg, P=0.04), with no change in the EDPVR. inferior vena cava occlusion also moved the ESPVR curve upward and leftward, indicating increased LV work per unit time. There was no augmentation of EDPVR following TEVAR (P>0.05). Postmortem exams in all animals revealed appropriate stent placement and no technical complications. TEVAR was associated with an acute increase in LV end-systolic pressure and shift in the ESPVR, indicating increased ventricular work. This data provides potential mechanistic insights into the development of post-TEVAR hypertension and heart failure. Future stent graft innovation should focus on minimizing the changes in cardiac physiology.

Ethnic & Sex Disparities in Type B Aortic Dissection Patients Undergoing Thoracic Endovascular Aortic Repair: An International Perspective

There has been a revolution in the management of type B aortic dissection (TBAD) over the last 2decades due to the increasing development of endovascular techniques, with the prime example being thoracic endovascular aortic repair (TEVAR). However, many controversies concerning the use of TEVAR in TBAD exist. For instance, there is little available evidence suggesting any differences in demographics, disease characteristics, intervention technicalities, and clinical outcomes between males and females as well as different ethnicities when undergoing TEVAR for TBAD, both in the short and long term. Also, there is no risk prediction model/tool available. The objective of this international study is to describe and delineate the disparities between male and female patients of different ethnicities in terms of demographics, disease and interventional characteristics, and clinical outcomes. Over 17years a total of 58 TBAD patients were admitted to 2 tertiary vascular centres and treated using TEVAR. Mortality, postoperative complications and reintervention data were recorded for the first 30days after the procedure as well as during follow-up. Follow-up for all patients lasted until the study endpoint or until a patient's death. Data were analysed retrospectively using IBM SPSS statistical package 26 for Windows. The mean age was similar between the 2 groups, with the majority of patients in both being Caucasian. More than half of the males had complicated TBAD, while the majority of females were classed as having uncomplicated disease. The most commonly utilized proximal and distal landing zone for the TEVAR stent graft was zone 2 and zone 4, respectively. The mean proximal stent diameter was significantly larger in males compared to females (P=0.004). The difference in mean distal diameter between the 2 groups was insignificant (P=0.721). The mean total stent coverage of the thoracic aorta was 251.3mm in male patients compared to 291.2mm in females (P=0.203). A total of 32 patients underwent adjunctive procedures. Seven (17%) of the males had one or more postoperative complications compared to 2 (12%) females. Nine (22%) males underwent a reintervention procedure post TEVAR compared to only 1 (6%) female (P=0.136). Overall, males had a mortality rate of 24% (n=10) compared to 41% of females (n=7) (P=0.201). Estimated survival of males and females post TEVAR was 80.4±9.6months and 69.7±14.4months (P=0.428). For the total population, the number of stent grafts was inversely correlated with mortality. Despite the favourable clinical outcomes achieved by TEVAR in TBAD, there remains a grey area concerning its management. Thus, it is important to perform risk stratification of individual patients using their demographics and comorbidities, particularly scrutinizing patient sex and ethnic origin, when considering intervention for TBAD to achieve optimum results.

Stent-Graft Migration Post-Endovascular Repair of Thoracic Aorta: A Retrospective Cohort Study.

Background Migration of the stent-graft post-thoracic endovascular aortic repair (TEVAR) is not uncommon; however, it is sparsely reported. The objective of this study was to assess the incidence, risk factors, and complications of stent-graft migration post-TEVAR. Materials and Methods Thirty-one patients who underwent TEVAR were retrospectively analyzed. The demographic, anatomical, and procedure-related factors were assessed. The measurements were done along the greater curvature of aorta around two fixed anatomic landmarks, that is, left common carotid artery or neoinnominate artery (hybrid repair) proximally and celiac artery distally. Aortic elongation and migration at proximal, distal, as well as at overlapping zone were measured. More than 10 mm of migration was considered significant. Results Significant migration was observed in six (19%) patients. No significant migration was observed in the overlapping zone. The proximal landing zone 3 (odds ratio [OR] 12.78, p 0.01) was a significant risk factor, whereas landing zone 2 was a protective factor against the migration (OR 0.08, p 0.02). The odds for migration were more in segments I/3 and II/3 compared with I/2 and II/2, respectively, as per Modified Arch Landing Areas Nomenclature. A single complication was seen in the migration group which was treated by an overlapping stent graft. Conclusion The stent-graft migration after TEVAR is not uncommon. Type 3 proximal landing zone was a significant risk factor for migration with an increased risk toward I/3 and II/3. Proximal landing zone 2 as well as adequate overlapping distance in multiple stent grafts can prevent migration. Ethical Approval No IECPG-227/24.06.2020

Impact of thoracic endovascular aortic repair on aortic biomechanics: Integration of in silico and ex vivo analysis using porcine model.

Thoracic endovascular aortic repair (TEVAR) is widespread in clinical practice for treating aortic diseases but it has relevant systemic complications, such as increase of the cardiac workload due to post-TEVAR aortic stiffening, and local issues such as re-entry tears due to the tissue damage caused by endograft interaction. The present study aims to elucidate these aortic biomechanical mechanisms by coupling ex vivo and in silico analysis. By ex vivo tests, the pulse wave velocity before and after TEVAR is measured. Uni-axial tensile tests are performed to measure regional mechanical response of tissue samples, supplied as input data for the in silico analysis. Numerical analysis is finally performed to compute the wall stress induced by the stent-graft deployment and the arterial pressurization. The ex vivo results highlight an increase of baseline PWV by a mean .78 m/s or 12% after TEVAR with a 100 mm stent-graft (p <.013). In the in silico analysis, the average von Mises stress in the landing zone increases of about 15% and 20% using, respectively stent-graft with radial oversizing of 10% and 20%. This work shows the effectiveness of integrated framework to analyze the biomechanical post TEVAR mechanisms. Moreover, the obtained results quantify the effect of prosthesis selection on the stiffening of the aorta after TEVAR and on the local increase of the aortic wall stress that is proportional to the stent-graft oversizing.

Stent Graft-induced Aortic Wall Injury: Incidence, Risk Factors, and Outcomes

BackgroundStent graft-induced new entry has been described in thoracic endovascular aortic repair for aortic dissection. The incidence of stent graft-induced aortic wall injury (SAWI) related to iatrogenic injury in nondissections is incompletely described. We describe incidence, risk factors, and outcomes of SAWI. MethodsAll post-thoracic endovascular aortic repair computed tomography angiograms (January 2005 to December 2018) were reviewed for radiographic evidence of SAWI. Endograft-induced aortic dissections were likewise considered SAWI. Patient characteristics, time to SAWI, and need for reintervention were noted. Cox proportional hazards modeling was used to identify risk factors for SAWI. ResultsWithin the study cohort (n = 430), 38 patients (9%) had SAWI during a median follow-up of 2.3 years (interquartile range, 4.8); 42% (n = 16) were proximal, 53% (n = 20) distal, and 5% (n = 2) both proximal and distal. Nine (23%) were distal intimal flap injuries in dissection cases, thus subclassifying them as stent graft-induced new entry. Twenty-nine percent of SAWI (n = 11) required reintervention. Of these, 45% (n = 5) were open, and 55% (n = 6) were endovascular. Thoracic endovascular aortic repair for acute dissection had a higher incidence of SAWI development (hazard ratio 4.6; 95% confidence interval, 2.4 to 9; P < .001) as compared with other indications. Use of devices with proximal bare springs or barbs was also associated with increased SAWI incidence (hazard ratio 5.3; 95% confidence interval, 2.6 to 11.0; P < .001). ConclusionsThe rate of SAWI after thoracic endovascular aortic repair is low (9%), but nearly one third will require reintervention. Thoracic endovascular aortic repair in the setting of acute dissection and use of devices with proximal bare springs or barbs were associated with an increased incidence of SAWI.

Prognostic Value of Preoperative Hemoglobin Levels for Long-Term Outcomes of Acute Type B Aortic Dissection Post-thoracic Endovascular Aortic Repair.

Background and Aims: There is scant information available about the prognostic value of preoperative hemoglobin (Hb) levels on the long-term outcomes of acute type B aortic dissection (ABAD) following thoracic endovascular aortic repair (TEVAR).Methods: A retrospective analysis of consecutive patients from 2010 to 2018 regarding the relationship between Hb level and long-term outcomes was conducted. The primary endpoint was all-cause mortality. Major adverse cardiovascular events (MACEs) included all-cause death, recurrent ruptures, and secondary procedures.Results: In total, 391 subjects treated by TEVAR were enrolled, with a mean age of 57.1 ± 12.0 years; 79.5% of them were male. Cox multivariate analysis showed that the preoperative Hb level was independently associated with all-cause death [adjusted hazard ratio (HR) 0.797 (per 1 g/dl), 95% confidence interval (CI) 0.693–0.918, p = 0.002] and MACEs (adjusted HR 0.795, 95% CI 0.672–0.871, p = 0.000). The area under the receiver operating characteristic curve of Hb for all-cause death and MACEs were 0.617 (95% CI 0.548–0.687, p = 0.008) and 0.617 (95% CI 0.551–0.684, p = 0.005), respectively. In the linear trend test, Hb concentration was significantly related to all-cause mortality (p for trend = 0.001) and MACEs (p for trend = 0.000). Moreover, in Kaplan–Meier analysis, lower Hb levels (< 12 g/dl) were significantly different from higher Hb (≥12 g/dl) levels for both all-cause death (log-rank p = 0.001) and MACEs (log-rank p = 0.001). Similar results were found when assessing the prognostic value of red blood cell count and anemia.Conclusions: Preoperative Hb may serve as a prognostic marker for long-range adverse outcomes for ABAD patients post-TEVAR.

Outcome After Endovascular Repair of Ruptured Thoracic Aortic Aneurysm: A National Multicenter Study

Introduction - Ruptured descending thoracic aortic aneurysm (rDTAA) is an acute condition with high mortality requiring urgent treatment. The purpose of this multicenter study was to analyze the outcome of thoracic endovascular aortic repair (TEVAR) in patients with rDTAA. Methods - This is a nationwide retrospective study including all patients who underwent TEVAR for rDTAA at six major vascular university centers in Sweden between January 2000 and December 2015. Data from local hospital records and the Swedish vascular registry at the participating centres were reviewed. Outcome measures were analysed using Kaplan-Meier estimator and multivariable Cox-regression. Results - There were 140 patients (mean age 74.1±SD 8.8 [range: 34-91] years; 56% men), with rDTAA. The mean descending aortic aneurysm size was 64.8±19 mm. Hemothorax was present in 64% (89/139) of patients at admission. The median stent graft length was 218 mm (range: 30-800 mm) and the median number of stentgrafts used was 2.0 (range: 1-6). In 53 patients (37.9%), the left subclavian artery was covered to extend the proximal landing zone. Twenty-five patients (17.9%) required proximal revascularization; chimney left carotid artery (n=14), chimney left subclavian artery (n=7), carotid-carotid-subclavian bypass (n=2), and left carotid-subclavian bypass (n=2). The celiac trunc was covered in 15 cases (10.7%) to achieve adequate distal landing zone. A chimney was placed in the SMA in six cases (4.3%) and in the celiac trunc in one case (0.7%). In two patients a multi branched stent graft was used. In total, 61/136 patients (45%) had a major complication within 30-day post TEVAR. Stroke (n=20; 14.7 %) was the most common complication followed by paraplegia (n=13; 9.6%) and major bleeding (n=13; 9.6 %). There were no association between stent graft length or subclavian coverage and paraplegia (OR 1.00, 95% CI 0.998-1.01; P=0.32, and OR 0.56, 95% CI 0.14-2.31; P=0.42; respectively) or subclavian coverage and stroke (OR 1.40, 95% CI 0.46-4.31; P=0.56). Reinterventions were required in 27/137 patients (19.7%). Postoperative bleeding was the only major complication associated with reintervention (OR 3.39, 95% CI 1.05-11.0; P=0.042). Median follow-up time was 18.5 months (range: 0-132 months). The Kaplan-Meier estimated survival was 79.1% at 1 month, 70.8% at 3 months, 64.5% at 1 year, 45.0% at 3 years, and 30.9% at 5 years. Age (HR 1.04; 95 % CI 1.00-1.07; P=0.044), previous stroke (HR 2.31; 95 % CI 1.17-4.55; P=0.016), previous aortic surgery (HR 2.17; 95 % CI 1.18-3.99; P=0.012) as well as postoperative major bleeding (HR 4.29; 95 % CI 2.14-8.60; P=0.001), postoperative stroke (HR 2.73; 95 % CI 1.43-5.22; P=0.002), and renal failure (HR 7.82; 95 % CI 2.53-24.19; P=0.001) were all associated with mortality. Conclusion - This nationwide multicenter study of patients with rDTAA undergoing TEVAR showed acceptable short-term survival but the long-term survival is rather poor. The postoperative complication rate is high and reinterventions are required in one fifth of patients. Patient selection and optimization are of utmost importance to improve outcome.

CT-Derived Pretreatment Thoracic Sarcopenia Is Associated with Late Mortality after Thoracic Endovascular Aortic Repair

Frailty, characterized by physiologic depletion, predicts postoperative morbidity and mortality in vascular surgery patients. CT-derived sarcopenia is a valuable method for objectively staging frailty preoperatively. With prior analyses primarily measuring psoas cross-sectional area on CT, we compared a method of measuring thoracic sarcopenia to existing techniques of lumbar sarcopenia and assessed the association with long-term survival and outcomes post-Thoracic Endovascular Aortic Repair (TEVAR). Prospectively collected data of 217 patients undergoing TEVAR from 2009 to 2012 were reviewed. Thoracic sarcopenia was quantified by measuring total area of the rectus abdominis, latissimus dorsi, intercostal, erector spinae, and external and internal oblique muscles at the T12 vertebral level. Total psoas area at the L3 was used to measure lumbar sarcopenia. 200 patients had preoperative imaging enabling measurements of thoracic sarcopenia, 186 of these patients were also assessed for lumbar sarcopenia. Thoracic sarcopenic patients were older, had lower body mass indices, were more commonly female, and most commonly being treated for aneurysms. Thoracic sarcopenic patients had significantly higher rates of congestive heart failure, hypertension, prior vascular intervention, and TEVAR-related adverse events. Thoracic sarcopenia was associated with significantly higher mortality at 2 and 5years post-TEVAR (2-year mortality: 19% vs 8%, P=0.02; 5-year mortality: 31% vs 18%, P=0.03). Lumbar sarcopenia was not associated with increased mortality at any time point. Patients whose muscle mass degraded over 48-month follow-up did not experience significantly higher rates of adverse events. CT-derived thoracic sarcopenia, but not lumbar sarcopenia, is significantly associated with 5-year mortality post-TEVAR.

The endovascular repair of blunt traumatic thoracic aortic injury in Asia: A systematic review and meta-analysis.

Blunt traumatic thoracic aortic injury, the second leading cause of death from trauma, poses unique challenges in its management. However, there has not yet been a corresponding consolidated series of outcomes reported in Asia, which this systematic review aims to address. This review was performed as per the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Searches were performed on MEDLINE, EMBASE, Google Scholar, and Cochrane Database for studies performed in Asia reporting the endovascular management of blunt traumatic thoracic aortic injury. Risk of bias was assessed using the Newcastle-Ottawa scale. Meta-analyses of pooled proportions were performed using the metaprop command in STATA. This review has been prospectively registered in PROSPERO (CRD42018083773). Sixteen retrospective cohort studies were included, reporting a total of 238 patients. The pooled Injury Severity Score was 32.5 (95%CI 27.8-37.1). The pooled mean time to operation from diagnosis was 39.2 hours (95%CI 24.6-53.8 hours), and operation time was 100min (95%CI 63.5-136.5min). The pooled rate of procedural conversion from endovascular repair to open surgery was 0.17% (95%CI 0-3.7%), and the proportion of left subclavian artery coverage was 55% (95%CI 37-72%). The pooled prevalence of intra-operative all-cause and aortic-related mortality was 0.72% (95%CI 0-4.9%) and 0.27% (95%CI 0-3.8%), respectively. The pooled prevalence of 30-day all-cause and aortic-related mortality was 2.2% (95%CI 0.16-5.6%) and 2.1% (95%CI 0-3.7%), respectively. In terms of 30-day complication, the pooled prevalence rates of type 1 endoleak, endograft complications, vascular access injury, strokes, and aortic re-rupture were 1.2%, 0.34%, 0.14%, 0.02%, and 0.01%, respectively. There were no cases of types II and III endoleak, and renal failure. Short- to mid-term results for thoracic endovascular aortic repair for blunt traumatic thoracic aortic injury in Asia are encouraging. However, there is a distinct disparity in reporting across Asia. We propose a prospective database for outcome reporting post thoracic endovascular aortic repair in this patient population, and ongoing follow up to assess long-term efficacy of this treatment strategy.

Aortoesophageal fistula postthoracic endovascular aortic repair

Thoracic endovascular aortic repair (TEVAR) is one of the choices for management of thoracic aortic aneurysms.[1] However, the complications of this procedure remain undetermined.[1] We present a 91 years male with a fatal post TEVAR aortoesophageal pseudoaneurysm leak and fistula to draw attention for such complication and its primary symptoms that may provide immediate treatment.

Cardiopulmonary-induced deformations of the thoracic aorta following thoracic endovascular aortic repair.

Thoracic endovascular aortic repair has become a preferred treatment strategy for thoracic aortic aneurysms and dissections. Yet, it is not well understood if the performance of endografts is affected by physiologic strain due to cyclic aortic motion during cardiac pulsation and respiration. We aim to quantify cardiac- and respiratory-induced changes of the postthoracic endovascular aortic repair thoracic aorta and endograft geometries. Fifteen thoracic endovascular aortic repair patients (66 ± 10 years) underwent cardiac-resolved computed tomography angiographies during inspiratory/expiratory breath holds. The computed tomography angiography images were utilized to build models of the aorta, and lumen centerlines and cross-sections were extracted. Arclength and curvature were computed from the lumen centerline. Effective diameter was computed from cross-sections of the thoracic aorta. Deformation was computed from the mid-diastole to end-systole (cardiac deformation) and expiration to inspiration (respiratory deformation). Cardiac pulsation induced significant changes in arclength, mean curvature, maximum curvature change, and effective diameter of the ascending aorta, as well as effective diameter of the stented aortic segment. Respiration, however, induced significant change in mean curvature and effective diameter of the ascending aorta only. Cardiac-induced arclength change of the ascending aorta was significantly greater than respiratory-induced arclength change. Deformations are present across the thoracic aorta due to cardiopulmonary influences after thoracic endovascular aortic repair. The geometric deformations are greatest in the ascending aorta and decline at the stented thoracic aorta. Additional investigation is warranted to correlate aortic deformation to endograft performance.

Risk of spinal cord ischemia after thoracic endovascular aortic repair.

Spinal cord ischemia (SCI) is a recognized grave complication after thoracic endovascular aortic repair (TEVAR). The present study aimed to evaluate the incidence and investigate risk of SCI after TEVAR based on current prophylactic strategies designed against established risk factors. The study retrospectively reviewed a prospectively maintained database to investigate patients who underwent TEVAR successfully between January 2009 and December 2012 in a single cardiovascular center. Detailed assessment of SCI risk was routinely performed for all patients before TEVAR was carried out. Prophylactic measures, including left subclavian artery (LSA) revascularization, blood pressure augmentation and cerebrospinal fluid (CSF) pressure control after TEVAR, were employed in high-risk patients and physical neurological examinations were regularly done to evaluate SCI after TEVAR. Patients were further divided into SCI group and non-SCI group. A total of 650 patients were enrolled in the study. Eleven patients (1.69%) developed SCI after TEVAR. Baseline level of hemoglobin was significantly lower in the SCI group (113.00 vs. 128.50, P=0.023). More patients in the SCI patients in the SCI group underwent TEVAR under general anesthesia (45.5% vs. 17.7%, P=0.033). A significantly higher incidence of post TEVAR hypotension was found in the SCI group (2.7% vs. 27.3%, P=0.004). Logistic regression analysis revealed that post-TEVAR hypotension (OR, 8.379; 95% CI, 1.833-38.304; P=0.006) was strongly associated with development of SCI and high normal baseline hemoglobin was a protective factor (OR, 0.969; CI, 0.942-0.998; P=0.037). The mortality in hospital and mortality at 1 year were not significant different between the SCI and the non-SCI group (0% vs. 1.6% P=1.000; 9.1% vs. 3.0%, P=0.294, respectively). While length of post-TEVAR stay (13.00 vs. 7.00 days, P=0.000) and length of hospital stay (20.00 vs. 13.00 days, P=0.001) were significantly greater in the SCI group. Our study revealed that, based on current prophylactic measures to curtail SCI, including LSA revascularization, blood pressure augmentation and CSF pressure control after TEVAR, post-TEVAR hypotension remains a major and independent risk factor for SCI and high normal baseline hemoglobin level is protective. SCI results in longer post-TEVAR stay and hospital stay, but not associated with increased mortality. Robust precautions should be taken against underlying causes for post-TEVAR hypotension and low level of hemoglobin should be avoided.

Treatment of post-thoracic endovascular aortic repair aorto-esophageal fistula-only radical surgery can be effective: techniques and sequence of treatment.

Aorto-esophageal fistulas (AEFs) are rare after thoracic endovascular aortic repair (TEVAR), being associated with the presence of mediastinal hematoma and the need for emergency TEVAR. Left untreated, AEFs are always lethal. "Redo"-stent-grafting can serve as a "bridging" procedure in hemodynamically unstable patients, but is not a durable therapy. Radical surgery is shown to be the most durable and effective treatment. This includes esophagectomy, stent-graft removal and aortic replacement followed by esophageal reconstruction, e.g., gastric pull-up operation. Aortic reconstruction can be performed by the use of self-made bovine pericardial tubes. A bilateral anterior ("clam-shell") thoracotomy can be chosen for surgical exposure in revision cases after previous sternotomy, in which the ascending aorta, aortic arch and proximal descending aorta require reconstruction.

MDCT angiography before and after thoracic endovascular aortic repair (TEVAR) in patients with thoracic traumatic aortic injuries

ObjectiveThe objective of this study was to outline the role of multidetector computed tomography angiography (MDCTA) in the evaluation of patients with thoracic traumatic aortic injuries (TTAIs) pre- and post-thoracic endovascular aortic repair (TEVAR) Subjects and methodsForty-two patients (30 men and 12 women; age range, 24–67 years; mean age, 42.4 ± 11.5 years) with blunt chest trauma who underwent TEVAR for TTAIs were retrospectively reviewed in this study during the 66-month review period. All patients were subjected to MDCTA followed by conventional aortography as part of planning for TEVAR. Postoperative MDCTA follow-up was done for all patients within one month of TEVAR. MDCTA findings before and after TEVAR were reported. ResultsThe most common TTAI site was the aortic isthmus (85.7%). The MDCTA findings in 42 patients included pseudoaneurysm (38), intimal tears (30), transection (16), intraluminal haematoma (2), dissection (2), periaortic haematoma (42), and minor aortic contour abnormality without pseudoaneurysm (2). The most common associated injury was haemothorax in all patients. Postoperative MDCTA follow-up revealed only two patients with type I endoleaks. ConclusionThis study confirmed that MDCTA plays an essential role in the assessment of patients with TTAIs before and after TEVAR.

Use of the Octopus Endograft Technique to Reconstruct Renovisceral Arteries Arising From the False Lumen of a Rapidly Expanding Type B Aortic Dissection After Endovascular Repair

Purpose: To describe the use and 6-month outcomes of the octopus endograft technique to reconstruct renovisceral arteries arising from the false lumen (FL) of a type B aortic dissection after thoracic endovascular aortic repair (TEVAR). Case Report: A 46-year-old man post TEVAR for type B aortic dissection was admitted with persistent back pain and a rapidly expanding residual dissection. The celiac and left renal arteries arose from the FL and the superior mesenteric artery from both lumens, with the FL as its main supply. A 20% oversized Endurant stent-graft was deployed with the short limb just above the beginning of the dissection flap and the long limb in the aortic true lumen. A 120-mm-long Endurant extended limb was delivered antegradely via a conduit and deployed into the FL, with a 3-cm overlap with the short limb of the Endurant main body. The 3 renovisceral arteries were reconstructed by lining each with a series of Viabahn or Fluency stent-grafts whose proximal ends were subsequently placed parallel in the FL Endurant extended limb and dilated with kissing balloons. Imaging at 6 months showed an excluded FL, without stenosis or occlusion in the stent-graft or the renovisceral arteries. Conclusion: This case illustrates the successful use of the octopus endograft technique to reconstruct renovisceral arteries arising from a rapidly expanding FL in a post-TEVAR type B aortic dissection; the technique might be applicable in carefully selected patients.

Retrograde Ascending Aortic Dissection After Thoracic Endovascular Aortic Repair for Distal Aortic Dissection or With Zone 0 Landing: Association, Risk Factors, and True Incidence

We attempted to determine the true incidence of retrograde ascending aortic dissection (rAAD) and to challenge its reported association with distal aortic dissection or zone 0 deployment. From January 2005 to August 2014, 305 patients who were at risk for rAAD underwent thoracic endovascular aortic repair. We excluded patients with prior ascending, hemiarch, or traditional or frozen elephant trunk grafts, or who required concomitant ascending graft placement. Patients in group A (n= 111, 36.4%) had distal aortic dissection or hematoma (n= 75, 67.6%) or required landing of the endograft in zone 0 of the native ascending aorta (n= 36, 32.4%). Patients in group B (n= 194, 63.6%) had nondissected descending or distal arch aneurysm (n= 172), penetrating ulcer (n= 9), coarctation (n= 6), endoleak not caused by dissection (n= 3), aortobronchial fistula (n= 3), or transection (n= 1). The incidence of rAAD was 1.3% overall (n= 4), 0.9% in group A (n= 1, Cook Zenith TX2), and 1.5% in group B (n= 3; 1 Talent Captivia, 2 Cook Zenith TX2; p= 0.64). No zone 0-treated patient had rAAD. Two patients from group B died, and 1 was treated nonoperatively. The median interval between thoracic endovascular aortic repair and rAAD was 11 days (range, 0 to 90 days). Post-thoracic endovascular aortic repair rAAD is a rare but lethal complication. Operator experience is crucial for prompt recognition and prevention. It does not appear that rAAD is specifically associated with distal aortic dissection or landing in zone 0. To our knowledge, this is one of the few studies to report the true incidence of rAAD in at-risk patients.

NP016 Complications post TEVAR for a Type B Aortic Dissection: A case study and review

Thoracic endovascular aortic repair (TEVAR) is rapidly becoming the standard for treatment of problematic Type B Aortic Dissections; with the open surgical procedures carrying a high rate of complications and mortality. TEVAR is a less invasive approach; stent grafts are deployed through the femoral artery and used to cover the intimal flap and aneurismal section of the descending aorta therefore relieving stress on the aorta. Post-op TEVAR patients have a different set of potential complications which can arise from graft migration, kinking, collapse, endovascular leaking, retrograde dissections and perforation of the fragile aortic tissues. The long-term outcomes of this therapy are still under investigation. TEVAR is an alternative to open surgical procedures, however complications can emerge. The first 72 hours post-op has the highest incidence of mortality in this patient population. Nursing staff are responsible for the daily care of patients post TEVAR and should be familiar with the possible complications and the associated signs and symptoms. During this presentation we will discuss the potential complications post TEVAR and have an in depth review of a case study to exemplify the possible hazards. In our case study the patient experiences several complications which make apparent the need for close follow-up both as an inpatient and in the community.