Retrograde type A aortic dissection after endovascular stent graft placement for treatment of type B dissection

Comparison of bare and nonbare stent grafts during thoracic endovascular aneurysm repair of the aortic arch

OBJECTIVE

We compared the outcomes of patients treated with nonbare stents (NBS) and proximal bare stents (PBS) endografts with a proximal landing zone in the aortic arch during thoracic endovascular aortic repair (TEVAR).

METHODS

We conducted a retrospective cohort, observational, multicenter study that included 361 consecutive TEVAR procedures undertaken between November 2005 and December 2021. TEVAR patients with both BS and NBS Relay stent graft configurations with proximal landing in zones 1, 2, or 3 were enrolled. Preoperative anamnestic and morphological data, clinical outcomes, and aortic modifications 30 days after surgery and at the latest follow-up available were collected. The primary outcome was freedom from proximal endoleak (type IA) comparing the two configurations. Total and detailed endoleak rates, clinical and technical success, intraoperative additional maneuvers, major adverse events, and reinterventions were secondary outcomes.

RESULTS

The median follow-up was 4.9 (interquartile range, 2.0-8.1) years. No statistically significant difference between NBS and PBS patients concerning 30-day major adverse events, retrograde aortic dissection, disabling stroke, or late type IA endoleak (10.8% vs 7.8%; P = .597). Aneurysmal disease (P = .026), PLZ diameter of >34 mm (P = .026), aortic tortuosity index of >1.4 (P = .008), type III aortic arch (P = .068), and PLZ thrombus (P = .014) identified as risk factors by univariate Cox regression analysis. PLZ thrombus was the only type IA endoleak risk factor at multivariate Cox regression (P = .016).

CONCLUSIONS

We found no statistically significant difference in freedom from type IA endoleak, retrograde dissection, or disabling stroke observed between the NBS and the BS configuration of the Relay endograft. Proximal landing zone thrombotic apposition was a prominent risk factor for type IA endoleak after TEVAR.

Efficacy of intentional undersized thoracic endovascular repair for Stanford type B aortic dissection

OBJECTIVE

Thoracic endovascular aneurysm repair (TEVAR) is widely used for the treatment of aortic dissection. Endograft oversizing is a risk factor for stent graft-induced new entry tears and retrograde type A aortic dissection. However, there is no clear consensus on the optimal graft size selection for Stanford type B acute or subacute aortic dissection (TBAD). Herein, we examined the safety and efficacy of TEVAR using an intentionally undersized endograft to treat TBAD.

METHODS

This retrospective chart review study included 82 patients who underwent TEVAR for acute or subacute Stanford TBAD between 2015 and 2022. We measured the true lumen diameter just distal to the subclavian artery and opted for a stent graft of the same diameter. In instances where deformation resulting from false lumen pressure displacement was pronounced, we measured the diameter at the site just proximal to the subclavian artery. Patients' characteristics, procedural, in-hospital, and follow-up data, and aortic remodeling were analyzed. The aortic diameter was analyzed using one-way analysis of variance followed by Dunnett's test. Survival and freedom from reintervention were estimated using Kaplan-Meier curves.

RESULTS

The follow-up rate was 98.4%. The mean age was 58.3 ± 12.3 years, and 76 were men (92.7%). The mean diameters of the stent graft and native proximal landing zone were 30.9 ± 3.2 mm and 30.8 ± 3.0 mm, respectively. The oversize rate of the stent graft in relation to the native proximal aortic diameter was 0.3% ± 4.7%. In-hospital mortality was observed in one patient, retrograde type A aortic dissection in one patient, distal stent graft-induced new entry tear in zero patients, and type 1a endoleak in 22 patients (26.8%). Type 1a endoleaks, characterized by antegrade false lumen blood flow originating from the primary entry, in 12 patients spontaneously disappeared within 1 year of follow-up. According to aortic remodeling, 59 patients (86.8%) achieved complete aortic remodeling at the aortic arch level and 51 (75.0%) at the eighth thoracic vertebral level. The diameters of the aortic arch and descending aorta were significantly reduced compared with the postoperative measurements (P <.001). Survival rates were 97.5% and 93.6% at 1 and 3 years, respectively. Freedom from reintervention was 84.7% and 84.7% at 1 and 3 years, respectively.

CONCLUSIONS

Intentionally undersized TEVAR was safe and achieved acceptable aortic remodeling despite a high rate of type 1a endoleaks. A type 1a endoleak was acceptable as it primarily diminished during the mid-term follow-up.

Surgical Treatment for Type A Aortic Dissection after Endovascular Aortic Repair: A 12-year, Single-Center Study

OBJECTIVE

This study aims to investigate the clinical manifestations, operative techniques, and outcomes of patients who undergo open repair after thoracic endovascular aortic repair (TEVAR).

METHODS

From January 2010 to June 2022, 113 consecutive type A aortic dissection (TAAD) patients underwent secondary open operation after TEVAR at our institution, and the median interval from primary intervention to open surgery was 12 (1.9-48.0) months. We divided the patients into two groups (RTAD (retrograde type A dissection) group, N = 56; PNAD (proximal new aortic dissection) group, N = 57) according to their anatomical features. Survival analysis during the follow-up was evaluated using a Kaplan-Meier survival curve and a log-rank test.

RESULTS

The 30-day mortality was 6.2% (7/113), the median follow-up period was 31.7 (IQR 14.7-65.6) months, and the overall survival at 1 year, 5 years, and 10 years was 88.5%, 88.5%, and 87.6%, respectively. Fourteen deaths occurred during the follow-up, but there were no late aorta-related deaths. Three patients underwent total thoracoabdominal aortic replacement 1 year after a second open operation. The RTAD group had a smaller ascending aorta size (42.5 ± 7.7 mm vs 48.4 ± 11.4 mm; P < .01) and a closer proximal landing zone (P < .01) compared to the PNAD group. However, there were no differences in survival between the two groups.

CONCLUSIONS

TAAD can present as an early or a late complication after TEVAR due to stent-grafting-related issues or disease progression. Open operation can be performed to treat TAAD, and this has acceptable early and mid-term outcomes. Follow-up should become mandatory for patients after TEVAR because these patients are at increased risk for TAAD.

Towards biomechanics-based pre-procedural planning for thoracic endovascular aortic repair of aortic dissection

BACKGROUND AND OBJECTIVE

Although thoracic aortic endovascular repair (TEVAR) has shown promising outcomes in the treatment of patients with complicated type B aortic dissection, complications still occur after TEVAR that can lead to catastrophic events. Biomechanical interactions between the stent-graft (SG) and the local aortic tissue play a critical role in determining the outcome of TEVAR. Different SG design may cause different biomechanical responses in the treated aorta, but such information is not known at the time of pre-procedural planning. By developing patient-specific virtual stent-graft deployment tools, it is possible to analyse and compare the biomechanical impact of different SGs on the local aorta for individual patients.

METHODS

A finite element based virtual SG deployment model was employed in this study. Computational simulations were performed on a patient-specific model of type B aortic dissection, accounting for details of the SG design and the hyperelastic behaviour of the aortic wall. Based on the geometry reconstructed from the pre-TEVAR CTA scan, the patient-specific aortic dissection model was created and pre-stressed. Parametric models of three different SG products (SG1, SG2 and SG3) were built with two different lengths for each design. The SG models incorporated different stent and graft materials, stent strut patterns, and assembly approaches. Using our validated SG deployment simulation framework, virtual trials were performed on the patient-specific aortic dissection model using different SG products and varying SG lengths.

CONCLUSION

Simulation results for different SG products suggest that SG3 with a longer length (SG3-long) would be the most appropriate device for the individual patient. Compared to SG1-short (the SG deployed in the patient), SG3-long followed the true lumen tortuosity closely, resulted in a more uniform true lumen expansion and a significant reduction in peak stress in the distal landing zone. These simulation results are promising and demonstrate the feasibility of using the virtual SG deployment model to assist clinicians in pre-procedural planning.

Thoracic Endovascular Aortic Repair on Zone 2 Landing for Uncomplicated Type B Aortic Dissection with Measurement of Intra-False Lumen Pressure

BACKGROUND

This study aimed to evaluate the midterm results of zone 2 thoracic endovascular aortic repair (TEVAR) for uncomplicated type B aortic dissection (TBAD) by measuring the intra-false lumen pressure (IFLP) during TEVAR.

METHODS

Fifteen patients (9 men; mean age, 57 years) who underwent zone 2 TEVAR for uncomplicated TBAD were reviewed. Delta systolic pressure (defined as the difference between systemic pressure and IFLP) was measured before and after primary entry closure, and aortic remodeling and thrombo-occlusion of the false lumen (FL) were evaluated 12 months after TEVAR at 5 different levels of the aorta.

RESULTS

Median duration from onset to TEVAR was 34 days. The left subclavian artery was preserved in 13 patients (87%) by using stent graft fenestration. Although 1 patient (6%) had a transient cerebral infarction, there were no severe TEVAR-related complications. Entry closure significantly reduced delta systolic pressure (mm Hg) compared to preoperative pressure at all levels (distal arch: -22.2 ± 10.8 vs. -5.2 ± 9.6; Th8: -20.1 ± 12.4 vs. -6.9 ± 7.2; Th10: -14.3 ± 14.6 vs. -4.7 ± 7.5; Th12: -14.4 ± 14.5 vs. -4.9 ± 7.8; L2: -14.5 ± 14.2 vs. -3.4 ± 6.9). The percentages of aortic remodeling with expansion of the true lumen (distal arch: 82%; Th8: 80%; Th10: 54%; Th12: 45%; L2: 50%) and complete false lumen thrombosis (distal arch: 100%; Th8: 100%; Th10: 67%; Th12: 11%; L2: 0%) were approximately consistent with the change in delta systolic pressure. During a follow-up of 41 months, distal stent-induced new entry occurred in 2 patients (13%) requiring secondary intervention; however, there were no cases of FL enlargement or aorta-related mortality.

CONCLUSIONS

Zone 2 TEVAR for uncomplicated TBAD may prevent TEVAR-related complications. Measuring IFLP could be a new predictive marker for assessing the extent of aortic remodeling.

Reinterventions after TEVAR

Thoracic cardiovascular aortic repair is an alternative procedure to open surgery for degenerative thoracic aortic aneurysm and thoracic aortic dissection. The advancements in graft design and imaging techniques have expanded its utility. However, the long-term patency of thoracic endovascular aortic repair (TEVAR) graft is still a concern. This review delves into the literature on re-intervention following TEVAR, highlighting factors that influence the re-intervention rate.

Prognosis and Remodeling after Endovascular Repair for Acute, Subacute, and Chronic Type B Aortic Dissection

PURPOSE

Thoracic endovascular aortic repair (TEVAR) for type B aortic dissection (TBAD) is already well introduced, but the best time point to perform TEVAR has not been defined. This study was to report mid- to long-term outcomes and aortic remodeling of TEVAR in patients with TBAD.

MATERIALS AND METHODS

In total, 318 TBAD patients from June 2001 to May 2016 were retrospectively reviewed. Patients were divided into 3 groups depending on interval between dissection onset to TEVAR: acute (0-7 days), subacute (8-30 days), and chronic (>30 days). Clinical and morphological data were collected and analyzed.

RESULTS

The follow-up aorta-related mortality rates in the 3 groups were 17.6%, 2.6%, 4.2%, and the proximal stent-induced new entry rates were 11.8%, 1.6%, 2.8%, respectively. Aortic remodeling was satisfied in both the acute and subacute group, but the false lumen diameter did not decrease (p>0.05) in the chronic group. Compared with the VIRTUE classification (acute, 0-14 days; subacute, 15-92 days; chronic, >92 days), mid- to long-term outcomes of patients within the first overlapped interval between the 2 classifications (8-14 days) were similar to that of subacute patients (15-30 days), while aortic remodeling of patients in the second overlapped interval (31-92 days) was similar to that of chronic patients (>92 days).

CONCLUSIONS

This study suggests that TEVAR for subacute TBAD is associated with a low long-term rate of aorta-related death. Aortic remodeling of chronic dissections is not satisfactory. Additional results suggest that the subacute phase (8-30 days) may be the optimal time to perform TEVAR for uncomplicated TBAD.

Finite-element simulation of in-plane tear propagation in the dissected aorta: Implications for the propagation mechanism

Computer modeling and numerical simulation are essential for understanding the progression of aortic dissection. However, tear propagation has not been properly modeled and simulated. The in-plane dissection propagation between concentrically distributed elastic lamellae is modeled using the cohesive zone method with a bilinear traction-separation law. The parameters of cohesive elements are calibrated for the three modes of interfacial damage in the media, enabling quantitative predictions of in-plane tear propagation. An idealized cylindrical tube-shaped bilayer thick-wall model of the aorta is employed to elucidate the influence of geometrical parameters, loading conditions and residual stress on the tear propagation. While the model is capable of replicating that deeper, larger tears are associated with lower critical pressure, new findings include: (i) Larger axial stretch leads to lower critical pressure; (ii) Increased magnitude of residual stress is associated with higher critical pressure; (iii) Pressure difference between true and false lumen alters the critical pressure; (iv) The interfacial damage is mostly opening mode in the axial direction, but shear-dominated in the circumferential direction; (v) Damage due to the opening mode is associated with smaller fracture energy, which makes it easier to propagate than the shear and the mixed modes. (vi) The deformed shape of the tear, which is related to its geometrical features and loading conditions, modulates the critical pressure via two pathways: (a) deformed shapes are associated with specific modes of damage, which influences the critical pressure, and (b) deformed shapes modulate the critical pressure directly via geometrical constraints.

Predictors of Return to Work After Thoracic Endovascular Aortic Repair in Patients With Type B Aortic Dissection

OBJECTIVE

Type B aortic dissection (TBAD) is a life-threatening condition, and it takes heavy burden to family and society. Return to work (RTW) not only means patients' physical health but also demonstrates their mental well-being. Thoracic endovascular aortic repair (TEVAR) has been successful in treatment of TBAD patients. However, less studies have addressed on the social functional recovery of TBAD after TEVAR, especially for RTW.

METHODS

From January 1, 2017 to January 1, 2021, TBAD patients who underwent TEVAR and completed a 12-month follow-up were retrospectively enrolled. Primary outcome was RTW. Patients' demographic, sociological, and clinical characteristics, and so on were recorded to analyze and demonstrate independent risk factors for RTW.

RESULTS

Four hundred thirty-two TBAD patients (388 males) were enrolled with a mean age of 48.3±8.9 years (ranged from 19 to 60 years). The 12-month cumulative RTW rate was 62.7% (95% confidence interval [CI]: 57.2%-67.8%). Age <50 years (odds ratio [OR]=3.675, 95% CI: 1.436-9.405) was identified as independent protective factors for RTW, while preoperative job as manual workers (OR=0.101, 95% CI: 0.029-0.353), average annual income, <30 000 Chinese Yuan (CNY) [<4400 US dollar], (OR=0.186, 95% CI: 0.054-0.637), complicated TBAD (malperfusion) (OR=0.246, 95% CI: 0.092-0.659), and distal stent graft-induced new entry (SINE) (OR=0.218, 95% CI: 0.083-0.575, p=0.002) were identified as independent risk factors.

CONCLUSION

Approximately 64% of our patients were able to RTW in the 12 months post-TEVAR for TBAD. Younger patients, patients with less physically demanding jobs, and patients with less complex surgeries were more likely to RTW. Based on these results, more can be done to facilitate the patient's ability and willingness to RTW after TEVAR.

CLINICAL IMPACT

Type B aortic dissection (TBAD) is a life-threatening condition that poses significant burden on both individuals and society. The ability to return to work (RTW) not only reflects the patient's physical health but also indicates their mental well-being. Therefore, identifying risk factors for RTW and promoting the reintegration of TBAD patients into the workforce is crucial in clinical practice.To our knowledge, this study is the first to elucidate and predict the RTW outcomes of TBAD patients who underwent thoracic endovascular aortic repair (TEVAR).

Hemodynamic parameters impact the stability of distal stent graft-induced new entry

Stent graft-induced new entry tear (SINE) is a serious complication in aortic dissection patients caused by the stent-graft itself after thoracic endovascular aortic repair (TEVAR). The stability of SINE is a key indicator for the need and timing of reinterventions. This study aimed to understand the role of hemodynamics in SINE stability by means of computational fluid dynamics (CFD) analysis based on patient-specific anatomical information. Four patients treated with TEVAR who developed a distal SINE (dSINE) were included; two patients had a stable dSINE and two patients experienced expansion of the dSINE upon follow-up examinations. CFD simulations were performed on geometries reconstructed from computed tomography scans acquired upon early detection of dSINE in these patients. Computational results showed that stable dSINEs presented larger regions with low time-averaged wall shear stress (TAWSS) and high relative residence time (RRT), and partial thrombosis was observed at subsequent follow-ups. Furthermore, significant systolic antegrade flow was observed in the unstable dSINE which also had a larger retrograde flow fraction (RFF) on the SINE plane. In conclusion, this pilot study suggested that high RRT and low TAWSS may indicate stable dSINE by promoting thrombosis, whereas larger RFF and antegrade flows inside dSINE might be associated with its expansion.

Retrograde type A aortic dissection during or after thoracic endovascular aortic repair: a single center 16-year experience

Objective

This article aims to investigate the incidence rate of retrograde type A aortic dissection (RTAD) and the risk factors of RTAD in relation to thoracic endovascular aortic repair (TEVAR).

Methods

Patients with thoracic aortic disease who underwent TEVAR at Henan Provincial People's Hospital from January 2004 to December 2019 were enrolled in the present research. The risk factors associated with RTAD following TEVAR using univariate and multiple logistic regression analyses.

Results

During the study period, A total of 1,688 TEVAR patients were included in this study, and of these, 1,592 cases were included in the type B aortic dissection (TBAD) group, and 96 cases were included in the non-TBAD group. There were 1,230 cases of aortic dissection and 362 cases of aortic intramural hematoma and/or penetrating ulcer in the TBAD group. The non-TBAD group included 68 cases of thoracic aortic aneurysm, 21 cases of thoracic aortic pseudoaneurysm, and seven cases of congenital aortic coarctation. The overall incidence rate of RTAD was 1.1% (18/1,688) in patients, all of which occurred in the TBAD group. The cohort comprised 18 RTAD patients with an average age of 56.78, consisting of 13 males and 5 females. Among them, 13 individuals exhibited hypertension. Ten instances happened within the TEVAR perioperative period, including two cases during the surgery, six cases occurred within three months, two cases occurred after one year, and the longest interval was 72 months following TEVAR. TEVAR was successfully implemented in 17 patients, while the operation technique was temporarily altered in one case. The new entry position for RTAD was identified as the proximal region of the stent graft (SG) in 13 patients, while in five cases, the entry site was more than 2 cm away from the proximal region of the SG. 17 cases were at the greater curvature of the aorta, and one case was at the lesser curvature. Multivariate logistic regression analysis revealed that the SG oversizing ratio is a relevant risk factor for RTAD. However, ascending aortic diameter, aortic arch type, SG type, and anchored region were not directly related to the occurrence of RTAD.

Conclusion

RTAD is a rare yet catastrophic complication. It could occur both during the procedure, early and late postoperative periods. Maintaining an appropriate SG oversizing ratio is crucial to minimize the risk of RTAD.

Safety and efficacy of thoracic endovascular aortic repair for acute Stanford type B aortic dissection with retrograde type A intramural hematoma

OBJECTIVE

The aim of this study was to evaluate safety and efficacy of thoracic endovascular aortic repair (TEVAR) for acute Stanford type B aortic dissection (TBAD) with retrograde type A intramural hematoma (TAIMH).

METHODS

Patients with acute TBAD with retrograde TAIMH treated with TEVAR between January 1, 2014, to March 31, 2022, were retrospectively reviewed. Aortic diameter and distance were measured using the 3D Slicer image computing platform. Patients' characteristics, procedural, in-hospital and follow-up data, and aortic remodeling were analyzed.

RESULTS

Fifty-two patients (average age, 52.6 years; 42 males [80.8%]) were included. The median interval from symptom onset to TEVAR was 11 days (interquartile range, 7.0-16.8 days). The maximal diameter of the ascending aorta (AA) was <50 mm, and the hematoma thickness in the AA was ≤10 mm in all patients. Both the in-hospital and 30-day mortality rates were 0%. The 30-day complication rate was 11.5%. The overall cumulative survival rates were 100% at 1 year, 97.1% at 3 years, and 92.6% at 5 years. Four of 52 patients (7.7%) developed retrograde type A aortic dissection at 10 days to 4 months postoperatively, and one of 52 patients (1.9%) developed an isolated AA dissection 4 months postoperatively; these five patients were treated and alive at late follow-up in March 2022. The rates of cumulative freedom from thoracic aortic re-intervention were 93.7% at 1 year and 90.7% at 5 years. Positive AA remodeling was observed in 92.3% (48/52) of patients during follow-up. The maximal diameter of AA (mean ± standard error of mean) at admission was 42.7 ± 0.8 mm, which decreased to 39.5 ± 0.9 mm at last follow-up. The maximal AA hematoma thickness at admission was 7.6 ± 0.3 mm, which reduced to 2.2 ± 0.9 mm at last follow-up.

CONCLUSIONS

For selected patients of acute Stanford TBAD with retrograde TAIMH, endovascular repair may be a safe, effective, and durable alternative treatment, if the maximum diameter of the AA is <50 mm and the intramural hematoma thickness in the AA is ≤10 mm.

In Marfan Syndrome and Related Diseases, STABILISE Technique Should Be Used with Care: Results from a Volumetric Comparative Study of Endovascular Treatment for Aortic Dissection

Objectives: Aortic dissection in patients with Marfan and related syndromes (HTAD) is a serious pathology whose treatment by thoracic endovascular repair (TEVAR) is still under debate. The aim of this study was to assess the results of the TEVAR for aortic dissection in patients with HTAD as compared to a young population without HTAD. Methods: The study received the proper ethical oversight. We performed an observational exposed (confirmed HTAD) vs. non-exposed (<65 years old) study of TEVAR-treated patients. The preoperative, 1 year, and last available CT scans were analyzed. The thoracic and abdominal aortic diameters, aortic length, and volumes were measured. The entry tears and false lumen (FL) status were assessed. The demographic, clinical, and anatomic data were collected during the follow-up. Results: Between 2011 and 2021, 17 patients were included in the HTAD group and 22 in the non-HTAD group. At 1 year, the whole aortic volume increased by +21.2% in the HTAD group and by +0.2% the non-HTAD groups, p = 0.005. An increase in the whole aortic volume > 10% was observed in ten cases (58.8%) in the HTAD group and in five cases (22.7%) in the non-HTAD group (p = 0.022). FL thrombosis was achieved in nine cases (52.9%) in the HTAD group vs. twenty (90.9%) cases in the non-HTAD group (p < 0.01). The risk factors for unfavorable anatomical evolution were male gender and the STABILISE technique. With a linear model, we observed a significantly different aortic volume evolution between the two groups (p < 0.01) with the STABILISE technique; this statistical difference was not found in the TEVAR subgroup. In the HTAD patients, there was a significant difference in the total aortic volume evolution progression between the patients treated with the STABILISE technique and the patients treated with TEVAR (+160.1 ± 52.3% vs. +47 ± 22.5%, p < 0.01 and +189.5 ± 92.5% vs. +58.6 ± 34.8%, p < 0.01 at 1 year and at the end of follow-up, respectively). Conclusions: TEVAR in the HTAD patients seemed to be associated with poorer anatomical outcomes at 1 year. This result was strongly related to the STABILISE technique which should be considered with care in these specific patients.

A systematic review and meta-analysis of retrograde type A aortic dissection after thoracic endovascular aortic repair in patients with type B aortic dissection

BACKGROUND

Retrograde type A dissection (RTAD) is a devastating complication of thoracic endovascular repair (TEVAR) with low incidence but high mortality. The objective of this study is to report the incidence, mortality, potential risk factors, clinical manifestation and diagnostic modalities, and medical and surgical treatments.

METHODS

A systematic review and single-arm and two-arm meta-analyses evaluated all published reports of RTAD post-TEVAR through January 2021. All study types were included, except study protocols and animal studies, without time restrictions. Outcomes of interest were procedural data (implanted stent-grafts type, and proximal stent-graft oversizing), the incidence of RTAD, associated mortality rate, clinical manifestations, diagnostic workouts and therapeutic management.

RESULTS

RTAD occurred in 285 out of 10,600 patients: an estimated RTAD incidence of 2.3% (95% CI: 1.9-2.8); incidence of early RTAD was approximately 1.8 times higher than late. Wilcoxon signed-rank testing showed that the proportion of RTAD patients with acute type B aortic dissection (TBAD) was significantly higher than those with chronic TBAD (P = .008). Pooled meta-analysis showed that the incidence of RTAD with proximal bare stent TEVAR was 2.1-fold higher than with non-bare stents: risk ratio was 1.55 (95% CI: 0.87-2.75; P = .13). Single arm meta-analysis estimated a mortality rate of 42.2% (95% CI: 32.5-51.8), with an I2 heterogeneity of 70.11% (P < .001).

CONCLUSION

RTAD is rare after TEVAR but with high mortality, especially in the first month post-TEVAR with acute TBAD patients at greater risk as well as those treated with proximal bare stent endografts.

Efficacy of left subclavian artery revascularization strategies during thoracic endovascular aortic repair in patients with type B dissection: A single-center experience of 105 patients

Background

Left subclavian artery (LSA) revascularization during thoracic endovascular aortic repair (TEVAR) is necessary to reduce postoperative complications in patients with Stanford type B aortic dissection and an insufficient proximal anchoring area. However, the efficacy and safety of different LSA revascularization strategies remain unclear. Here, we compared these strategies to provide a clinical basis for selecting an appropriate LSA revascularization method.

Methods

In this study, we included 105 patients with type B aortic dissection who were treated using TEVAR combined with LSA reconstruction in the Second Hospital of Lanzhou University from March 2013 to 2020. They were divided into four groups according to the method used for LSA reconstruction, namely, carotid subclavian bypass (CSB; n = 41), chimney graft (CG; n = 29), single-branched stent graft (SBSG; n = 21), and physician-made fenestration (PMF; n = 14) groups. Finally, we collected and analyzed the baseline, perioperative, operative, postoperative, and follow-up data of the patients.

Results

The treatment success rate was 100% in all the groups, and CSB + TEVAR was the most commonly used procedure in emergency settings compared with the other three procedures (P &lt; 0.05). The estimated blood loss, contrast agent volume, fluoroscopic time, operation time, and limb ischemia symptoms during the follow-up were significantly different in the four groups (P &lt; 0.05). Pairwise comparison among groups indicated that the estimated blood loss and operation time in the CSB group were the highest (adjusted P &lt; 0.0083; P &lt; 0.05). The contrast agent volume and fluoroscopy duration were the highest in the SBSG groups, followed by PMF, CG, and CSB groups. The incidence of limb ischemia symptoms was the highest in the PMF group (28.6%) during the follow-up. The incidence of complications (except limb ischemia symptoms) during the perioperative and follow-up periods was similar among the four groups (P &gt; 0.05) The median follow-up time of CSB, CG, SBSG, and PMF groups was significantly different (P &lt; 0.05), and the CSB group had the longest follow-up.

Conclusion

Our single-center experience suggested that the PMF technique increased the risk of limb ischemia symptoms. The other three strategies effectively and safely restored LSA perfusion in patients with type B aortic dissection and had comparable complications. Overall, different LSA revascularization techniques have their advantages and disadvantages.

Long-term outcomes of endovascular treatment for aortic pseudoaneurysm in patients with Behçet's disease

OBJECTIVES

Behçet's disease (BD) is a multisystem inflammatory disorder with unknown etiology, and its aneurysmal lesions are associated with high mortality due to the high risk of rupture. This study intended to further explore the long-term safety and efficacy of endovascular therapy for BD-related aortic pseudoaneurysm (BAP).

METHODS

From January 2009 to May 2021, 17 BAP patients who underwent endovascular repair were retrospectively identified and enrolled. Adequate immunosuppressive treatment was instituted before and after endovascular treatment unless emergency surgery was required. The patients were followed up at 3, 6, and 12 months and yearly after the primary endovascular intervention by computed tomography angiography (CTA) examination.

RESULTS

Nineteen BAPs were identified among 17 patients. BAPs located at the aortic arch were found in three patients (17.6%), descending thoracic aorta in 5 (29.4%), and abdominal aorta in 10 (58.8%; suprarenal abdominal aorta in 2 [11.8%], and infrarenal abdominal aorta in 8 [47.1%]). The mean ESR during admission was 56.5 ± 24.9 mm/h (range = 30.0-120.0 mm/h), which fell to 22.7 ± 18.4 mm/h (range = 2.0-74.0 mm/h) before the endovascular intervention (p < 0.001). The rate of favorable immunosuppressive control before intervention is 76.5% (13/17). Technical success was achieved in all patients. Median follow-up time was 57.0 months (interquartile range [IQR] = 21.3-67.3 months). Pseudoaneurysm recurrence was observed in four patients, type I endoleak in one, pseudoaneurysms sac dilation in one, and external iliac artery occlusion in 1. Two patients died of pseudoaneurysm rupture. Five-year accumulated overall rate, recurrence-free rate, and reintervention-free survival rate of BAP patients were 92.8%, 75.4%, and 71.8%, respectively.

CONCLUSION

Endovascular treatment in BAP patients seemed to be associated with long-term safety and efficacy with a 5-year overall survival rate of 92.8%. Adequate immunosuppressive treatment was essential for BAP patients to prevent aortic pseudoaneurysm recurrence and improve the prognosis.

Meta-analysis and meta-regression of the total endovascular aortic repair in aortic arch

Background: The total endovascular repair of the aortic arch is becoming more and more an acceptable alternative to the open repair in selected patients. The aim of the present study is to perform a meta-analysis of the available data on the outcomes of the various endovascular techniques used to treat the pathologies in this challenging anatomical area. Patients and methods: An extensive electronic search in PubMed/MEDLINE, Science Direct Databases, and the Cochrane Library was conducted. All papers published up to January 2022 on the endovascular techniques in the aortic arch (chimney-thoracic endovascular aortic repair (ChTEVAR), fenestrated/branched grafts as custom made devices (CMD) and surgeon modified TEVAR (SM TEVAR) providing information about at least one of the essential outcomes defined in the inclusion criteria. Results: Out of the 5078 studies found through the search in the databases and registers, 26 studies with a total number of patients of 2327 with 3497 target vessels were included in the analysis. The studies reported a high technical success rate with an estimated proportion of 95.8% (95% CI, 93-97.6%). Moreover, the pooled estimation of the early type Ia/III endoleak was 8.1% (95% CI, 5.4-12.1%). The pooled mortality was 4.6% (95 CI, 3.2-6.6%) with a significant heterogeneity and the stroke had an estimated proportion (major and minor combined) of 4.8% (95% CI, 3.5-6.6%). A meta-regression analysis showed no significant variation between the groups in mortality (P=.324) showed however a significant difference between the therapeutic methods regarding stroke P<.001 (lower rate in ChTEVAR and SM vs. CMD). Conclusions: The present meta-analysis could demonstrate good short- and long-term outcomes of the multiple total endovascular repair methods used in the aortic arch.

Prognostic Value of the Systemic Immune Inflammation Index after Thoracic Endovascular Aortic Repair in Patients with Type B Aortic Dissection

The study aimed at investigating the association between postoperative inflammatory scores and aorta-related adverse events (AAEs) after thoracic endovascular aortic repair (TEVAR) for patients with type B aortic dissection (TBAD). This single-centre, retrospective cohort included all patients who underwent TEVAR for TBAD between November 2016 and November 2020 at a university hospital. The risk factors for AAEs were analyzed by Cox proportional hazards model regression. Prediction accuracy was assessed using the area under the receiver operating characteristic curves. This study included 186 patients with a mean age of 58.5 years and a median follow-up period of 26 months. A total of 68 patients developed AAEs. Age and postoperative systemic immune inflammation index (SII) (>2893) were associated with post-TEVAR AAEs (hazard ratio (HR) 1.03, p = 0.003; HR 1.88, p = 0.043, respectively). Increased postoperative SII and age are independent risk factors for AAE post-TEVAR in patients with TBAD.

Reintervention after Thoracic Endovascular Aortic Repair of Uncomplicated Type B Aortic Dissection

BACKGROUND

Data are scarce regarding the incidence, reasons, potential risk factors, and long-term outcomes of reintervention after thoracic endovascular aortic repair (TEVAR) in patients with uncomplicated type B aortic dissection (TBAD).

METHODS

Between January 2010 and December 2020, 238 patients with uncomplicated TBAD who received TEVAR were analyzed retrospectively. The clinical baseline data, aorta anatomy, dissection characteristics, and details of the TEVAR procedure were evaluated and compared. A competing-risk regression model was used to estimate the cumulative incidences of reintervention. The multivariate Cox model was used to identify the independent risk factors.

RESULTS

The mean follow-up time was 68.6 months. A total of 27 (11.3%) cases of reintervention were observed. The competing-risk analyses showed that the 1-, 3-, and 5-year cumulative incidences of reintervention were 5.07%, 7.08%, and 14.0%, respectively. Reasons for reintervention included endoleak (25.9%), aneurysmal dilation (22.2%), retrograde type A aortic dissection (18.5%), distal stent-graft-induced new entry and false lumen expansion (18.5%), and dissection progression and/or malperfusion (14.8%). Multivariable Cox analysis demonstrated that a larger initial maximal aortic diameter (Hazard ratio [HR], 1.75; 95% Confidence interval [CI], 1.13-2.69, p = 0.011) and increased proximal landing zone oversizing (HR, 1.07; 95% CI, 1.01-1.47, p = 0.033) were the significant risk factors for reintervention. Long-term survival rates were comparable between patients with or without reintervention (p = 0.915).

CONCLUSIONS

Reintervention after TEVAR in patients with uncomplicated TBAD is not uncommon. A larger initial maximal aortic diameter and excessive proximal landing zone oversizing are associated with the second intervention. Reintervention does not significantly affect long-term survival.

Midterm outcomes of isolated thoracic aortic replacement in congenital versus degenerative aortopathy in a 15-year institutional cohort

BACKGROUND

Open aortic replacement represents the only approved option to address thoracic aortopathy among patients with connective tissue disorders (CTD). The aim of our study was to investigate contemporary midterm outcomes of isolated thoracic aortic replacement in patients with CTD versus degenerative pathology in a large institutional cohort.

METHODS

All patients undergoing isolated open thoracic aortic replacement at a single academic center from 2005 to 2020 were included. Patients were classified as having CTD or not having CTD based on documented genetic mutations associated with congenital aortopathy. In-hospital and midterm outcomes, including mortality, paraplegia, development of new arterial pathology on surveillance imaging, and the need for future operations, were compared between groups using descriptive statistics and Kaplan-Meier survival analysis.

RESULTS

Overall, 62 patients were included with a median follow-up of 58 months (range, 19-81 months) (59 months for those with CTD vs 51.5 months for those without CTD). CTD was present in 18 patients (29%), with 16 having Marfan syndrome (77.8%). Patients with CTD were younger than patients without CTD (45.8 years vs 60.9 years) and had lower rates of smoking (5.6% vs 56.8%) and hypertension (97.7% vs 72.2%; all P < .01). Patients with CTD were more likely to have a dissection component at the time of repair compared with patients without CTD (100% vs 59.1%) and underwent repair at smaller aortic diameters (5.9 cm vs 6.6 cm; both P < .05). There were no differences in in-hospital outcomes between the two groups, including mortality (4.5% vs 5.6%) and paraplegia (2.3% vs 0%; both P > .05). At 5 years, patients with CTD were more likely to have developed aneurysmal changes distal to their thoracic repair (88.9% vs 47.7%) and extra-aortic arterial aneurysms (41.2% vs 2.3%; both P < .05). However, on survival analysis, there were no differences in freedom from additional vascular procedures (hazard ratio,1.76; P = .333) or, specifically, additional aortic procedures (hazard ratio, 1.81; P = .380) between the two groups. There was only one anastomotic complication identified on longitudinal follow-up, which occurred in a patient without CTD 8 years after the index operation.

CONCLUSIONS

Although carrying significant operative risks and the potential for morbidity, open thoracic aortic replacement represents a well-tolerated, durable treatment option for patients with congenitally mediated thoracic aortic disease. Because both patients with and without CTD who required thoracic aortic replacement often need future aortic intervention, vigilant surveillance is warranted. Equivalent intervention rates between the two groups suggest remodeling of the CTD aorta is almost universally characterized by initial postrepair dilation, but the majority of these changes successfully stabilize and do not progress to higher rates of intervention.

Risk factors for distal stent graft-induced new entry after endovascular repair in uncomplicated type B aortic dissection

OBJECTIVE

We investigated the risk factors for distal stent graft-induced new entry (dSINE) after thoracic endovascular aortic repair for patients with uncomplicated type B aortic dissection (TBAD) and reported the outcomes of using a tapered stent graft and dSINE reintervention.

METHODS

A total of 226 patients with uncomplicated TBAD who had undergone thoracic endovascular aortic repair between January 2010 and December 2018 were analyzed retrospectively. The global features of the thoracic aorta and the local features of the proximal and distal landing zones were evaluated and compared between the dSINE and non-dSINE groups. A multivariate Cox model was used to identify the independent risk factors for dSINE. The cumulative incidence of reintervention was estimated using competing risk models.

RESULTS

After a median follow-up of 4.6 years, 16 patients (7.1%) had developed dSINE. Multivariable Cox regression analysis demonstrated that a type III aortic arch, decreased angle, increased distal oversizing, and increased distal mismatch ratio were significant risk factors for dSINE. Of the patients with tapered stent grafts, five with a ≤4-mm taper had developed dSINE. However, no dSINE was seen in the >4-mm taper group (P = .024). Reintervention was performed for 7 of the 16 patients with dSINE (43.8%). The mean time from the initial detection of dSINE to reintervention was 6.43 ± 4.62 months. The competing risk analyses showed that the cumulative incidence of reintervention in the dSINE group at 1, 3, and 5 years was 25.0%, 37.5%, and 43.5%, respectively.

CONCLUSIONS

A type III aortic arch, excessive distal oversizing and mismatch ratio, and severe angulation were associated with dSINE in patients with uncomplicated TBAD. The use of a tapered stent graft with a >4-mm taper could help prevent dSINE in patients with a high taper ratio. Aggressive reintervention was associated with favorable long-term outcomes for patients with progressive dSINE.

Single-branched stent-graft with on-table fenestration for endovascular repair of primary retrograde type A aortic dissection: A multicenter retrospective study

Objective

This study aims to evaluate the feasibility, efficacy, and safety of a single-branched stent-graft with on-table fenestration for primary retrograde type A aortic dissection (RTAD) during thoracic endovascular aortic repair (TEVAR).

Materials and methods

From January 2019 to December 2021, 36 patients with primary RTAD from five tertiary hospitals received medical management in the acute phase. They underwent TEVAR with a proximal zone 1 landing for aortic arch reconstruction in the subacute phase, using a fenestration technique on a single-branched stent-graft. Nearly 2 weeks after admission, computed tomography angiography (CTA) was re-examined to evaluate the thrombosis status of retrograde false lumen (FL). The primary outcomes were technical success, patency of the target branch arteries, and absence of type Ia endoleaks. The second outcomes were stent-graft-related complications and all-cause mortality.

Results

The mean age was 56.2 ± 11.3 years, and 29 (80.6%) were male. After a median interval of 18.0 [interquartile range (IQR), 17.0–20.3] days of medical treatment, the partial and complete thrombosis of proximal FL rates increased to 52.8% and 47.2%, respectively. One patient (2.8%) experienced postoperative type Ia endoleaks, and was successfully re-treated using coli and Onyx glue. The median hospital stay was 20.5 (IQR, 18.0–23.0) days. The overall technical success rate was 100%. The median follow-up time was 31.5 (IQR, 29.8–34.0) months. There was one death (2.8%) due to gastrointestinal bleeding. Distal aortic segmental enlargement (DASE) occurred in two (5.6%) patients. No major complications or recurrent dissections in the proximal landing zone were recorded during follow up.

Conclusion

The retrograde FL in primary RTAD could realize partial or complete thrombosis after medical management in the acute phase, and it might be regarded as a valid proximal landing zone for endovascular repair. The single-branched stent graft with on-table fenestration performed in the subacute phase may be feasible strategy in selective primary RTAD patients.

Long-Term Outcomes of Chronic Type B Aortic Dissection Treated by Thoracic Endovascular Aortic Repair

Background The treatment of chronic type B aortic dissection by thoracic endovascular aortic repair has some challenges, and its long-term outcomes remain unclear. This study aimed to analyze the 5-year clinical outcomes of thoracic endovascular aortic repair of chronic type B aortic dissection, compare the differences between patients with and without adverse aortic events (AAEs), and identify risk factors for AAEs. Methods and Results Patients who underwent thoracic endovascular aortic repair of chronic type B aortic dissection from January 2009 to June 2017 were retrospectively enrolled. The primary end points were AAEs, including aorta-related death, procedural complications, and disease progression requiring reintervention. Clinical outcomes were described at the 5-year follow-up visit. The secondary end point was the comparison of the results between patients with and without AAEs. Univariable and multivariable logistic analyses were used to identify potential risk factors for AAEs. A total of 214 patients were enrolled. AAEs occurred in 46 (21.5%) patients. Compared with patients without AAEs, those with AAEs had higher rates of residual type A aortic dissection (26.1% versus 4.2%, P<0.001) and aortic diameter ≥5.5 cm (69.6% versus 11.3%, P<0.001), and a lower rate of complete false lumen thrombosis (23.9% versus 89.9%, P<0.001). Meanwhile, the median interval from symptom onset to intervention was longer in patients with AAEs (26 months versus 12 months, P=0.004). Partial or no false lumen thrombosis (adjusted odds ratio [AOR], 14.71 [95% CI, 5.67-38.14; P<0.001]) and aortic diameter ≥5.5 cm (AOR, 10.16 [95% CI, 3.86-26.73; P<0.001]) were identified as independent risk factors for AAEs. Conclusions While thoracic endovascular aortic repair of chronic type B aortic dissection might be challenging in some cases, its long-term outcomes appeared promising as this treatment was effective in preventing catastrophic aortic events. Patients with AAEs showed higher rates of residual type A aortic dissection and aortic diameter ≥5.5 cm, a lower rate of complete false lumen thrombosis, and a longer median interval from symptom onset to intervention. Failure of complete false lumen thrombosis and an aortic diameter ≥5.5 cm were predictors of AAEs.

Retrograde ascending aortic dissection in the midterm period after thoracic endovascular aortic repair: a case report and literature review

Retrograde ascending aortic dissection (rAAD) is a catastrophic complication of thoracic endovascular aortic repair (TEVAR). A 56 year-old male patient who had undergone TEVAR for Stanford type B aortic dissection 6-month ago was admitted to our clinic with uncontrolled hypertension for the last twelve hours and history of a syncopal attack three days ago. Retrograde ascending aortic dissection was detected in computed tomography angiography. Ascending aorta and hemiarch replacement with a Dacron graft was safely performed via hypothermic circulatory arrest and antegrade cerebral perfusion for the treatment of rAAD after TEVAR.

Five-Year Results of Aortic Remodeling for Acute, Subacute, and Chronic Type B Aortic Dissection Following Endovascular Repair

Background

This study was performed to compare aortic remodeling and clinical outcomes in patients with acute, subacute, and chronic type B aortic dissection (TBAD) after thoracic endovascular aortic repair (TEVAR).

Methods

We retrospectively examined 323 consecutive patients with acute (n = 129), subacute (n = 161), and chronic (n = 33) TBAD who underwent TEVAR from June 2013 to December 2016 in in multicenter institution. Patient demographics, clinical data, and imaging characteristics were recorded and compared among the three groups.

Results

The three groups had comparable baseline characteristics. Perioperative mortality rates were similar among the acute (2.3%), subacute (0.0%), and chronic (0.0%) groups (P = 0.34). Perioperative morbidity rates, including the rates of visceral and lower limb malperfusion and cerebral infraction, were also similar. The rate of perioperative endoleak was significantly higher in the chronic group (18.1%) than in the acute (3.9%) and subacute (3.7%) groups (P = 0.02). The mean follow-up duration was 78 ± 22 months (range, 36–101 months). The mortality rates were comparable among the three groups. The rates of reintervention and lower limb malperfusion were higher in the chronic group than in the acute and subacute groups. FL diameter reduction were more robust in the acute and subacute groups than in the chronic group.

Conclusion

Patients with acute, subacute, and chronic TBAD had different outcomes in this study. Patients with acute and subacute TBAD had fewer complications than those with chronic TBAD. Aortic remodeling after TEVAR was more favorable in patients with acute and subacute TBAD than in patients with chronic TBAD. TEVAR promotes more positive remodeling at the stent graft level than at the distal level of the aorta.

Systematic review and meta-analysis of current evidences in endograft therapy versus medical treatment for uncomplicated type B aortic dissection

OBJECTIVE

Best medical therapy (BMT) should be recommended for treating uncomplicated Stanford type B aortic dissection (uSTBAD), whereas thoracic aortic endovascular repair (TEVAR) has been controversial for uSTBAD.

METHODS

In this paper, a meta-analysis was conducted on all available randomized controlled trials and observational studies that evaluated the relative benefits and harms of TEVAR and BMT for the management of patients suffering from uSTBAD. Primary endpoints consisted of early adverse events, long-term adverse events and aortic remodeling. In addition, Risk difference (RD) or Odds ratios (OR) with 95% confidence intervals (CI) were estimated. The random effects model or the fixed-effects model was used in accordance with the 50% heterogeneity threshold.

RESULTS

Seven observational studies and two RCT studies from 11 articles that contained 15066 patients suffering from uSTBAD (1518 TEVARs) met the inclusion criteria. For early outcomes, no significant differences were found between the TEVAR group and the BMT group in aortic rupture, retrograde dissection, paraplegia/paraparesis, reintervention, aorta-related death and all caused death. In the long run, the TEVAR group was found to have a significantly lower incidence of adverse events, which included aortic rupture (OR:0.26, CI:0.16∼0.42, P<0.05; heterogeneity: P=0.90, I²=0%), reintervention (OR:0.45, CI:0.26∼0.75, P<0.05; heterogeneity: P=0.17, I²=41%), aorta-related death (OR:0.27, CI:0.18∼0.42, P<0.05; heterogeneity: P=0.61, I²=0%) and all caused death (OR:0.52, CI:0.42∼0.66, P<0.05; heterogeneity: P=0.05, I²=53%) as compared with the BMT group. Moreover, in compared with BMT, TEVAR was found to significantly contribute to the complete thrombosis of thoracic false lumen (OR:55.34, CI:34.32∼89.21, P<0.05; heterogeneity: P=0.97, I²=0%) and aortic regression (true lumen expansion and false lumen shrinkage).

CONCLUSIONS

Although early endovascular repair of uSTBAD does not outperform BMT, its implementation is found to be necessary to facilitate the long-term prognosis. Accordingly, if early TEVAR is to be deferred, close follow-up is critical to allow for timely reintervention.

Surgical Repair of Two Kinds of Type A Aortic Dissection After Thoracic Endovascular Aortic Repair

Background

Retrograde dissection is now recognized as an important complication following thoracic endovascular aortic repair (TEVAR). The purpose of this study is to describe two different situations of TAAD after TEVAR. We will introduce the surgical methods used to repair TAAD following TEVAR at our center, and evaluate its long-term prognosis.

Methods

Between January 2010 and October 2019, 50 patients who had previously received TEVAR treatment for TBAD were admitted to our center for repair of a type A aortic dissection. According to the patients’ CT angiographies and intra-operative findings, we identified two distinct groups: a retrograde group (stent-induced new aortic injury, with retrograde extension involving the ascending aorta) and an antegrade group (entry tear located in the aortic root, ascending aorta or the aortic arch, away from the edges of the stent grafts). The options for treatment of the proximal aorta were Bentall procedure (12/50, 24.0%) and ascending aorta replacement (38/50, 76.0%). All patients underwent total arch replacement (TAR) and frozen elephant trunk (FET) implantation. Survival over the follow-up period was evaluated with the Kaplan–Meier survival curve and the log-rank test.

Results

The median interval time from prior TEVAR to reoperation was 187 days (IQR: 30.0, 1375.0 days). 18.0% of TAAD after TEVAR did not have any obvious symptoms at the time of diagnosis, most of which were found on routine follow-up imaging. The patients in the retrograde group were younger than those in the antegrade group (44.0 ± 9.4 vs. 51.4 ± 10.5 years, P = 0.012). No significant differences in the incidence of post-operative complications or mortality were noted between the two groups. The mean follow-up time was 3 years. No late death or complications occurred after one year following surgery upon follow-up. The asymptomatic survival rate one year after surgery was 90.0%.

Conclusion

The TAR and FET technique was feasible and effective for complicated TAAD after TEVAR. The surgical success rate and long-term prognosis of patients undergoing the timely operation are satisfactory.

Clinical Results and Aortic Remodeling After Endovascular Treatment for Complicated Type B Aortic Dissection With the “Fabulous” Stent System

Objective

To report the clinical outcomes and aortic remodeling after the implantation of a self-developed, biomechanically optimized, two-stage thoracic stent system named Fabulous.

Background

Given the efficacy of the PETTICOAT concept, the benefits of Fabulous and the behavior of remodeling in different segments need further investigation.

Methods

This is a prospective and multicenter study. From 2017 to 2019, 145 patients (mean age, 56.6 years; 88.3% male) from 14 centers were included in this cohort. The clinical results and core laboratory results were from a central electronic data capture system. Computed tomographic angiography was performed preoperatively, 1 month, 6 months and yearly thereafter and was used for volumetric analysis by 3mensio (Bilthoven, The Netherlands). After the 1-year follow-up, 97.2 and 87.6% of the clinical and imaging results of the eligible patients were available.

Results

Both stent grafts and bare stents were successfully delivered in place in 100% of the patients. The 30-day mortality and 1-year freedom from all-cause mortality were 2.1 and 96.6%, respectively. The incidence of entry flow was 11.7% at 30 days and 6.2% at 365 days. No cases of stent-induced new entry (SINE) or reintervention were observed. After the 1-year follow-up, the true lumen/overall volume ratio reached 88%. The following subdivided segment volume changes were recorded: stent graft segment TL +56%; FL −92%, bare stent segment TL +32%; FL −75%, and there were no significant changes in the visceral segment.

Conclusions

These outcomes indicated that there were favorable clinical benefits of Fabulous stent system. This device achieved a low short-term mortality and a low incidence of reintervention. In addition, patients undergoing Fabulous stent system implantation showed remodeling both on descending aorta and on the distal aorta. The volume changes in the TL and FL varied in the different segments. The long-term follow-up is still ongoing.

Thoracic endovascular repair of chronic type B aortic dissection: a systematic review

BACKGROUND

At present, the optimal management strategy for chronic type B aortic dissection (CTBAD) remains unknown, as equipoise remains regarding medical management versus endovascular treatment versus open surgery. However, the results over recent years of thoracic endovascular aortic repair (TEVAR) in CTBAD appear promising. The aim of this systematic review was to provide a comprehensive analysis of the available data reporting outcomes and survival rates for TEVAR in CTBAD.

METHODS

Electronic searches of six databases were performed from inception to April 2021. All studies reporting outcomes, specifically 30-day mortality rates, for endovascular repair of CTBAD were identified. Relevant data were extracted, and a random-effects meta-analysis of proportions or means was performed to aggregate the data. Survival data were pooled using data derived from original Kaplan-Meier curves, which allows reconstruction of individual patient data.

RESULTS

Forty-eight studies with 2,641 patients were identified. Early (<30 days) all-cause and aortic-related mortality rates were low at 1.6% and 0.5%, respectively. Incidence of retrograde type A dissection in the post-operative period was only 1.4%. There were also low rates of cerebrovascular accidents and spinal cord injury (1.1% and 0.9%, respectively). Late follow-up all-cause mortality was 8.0%, however, late aortic-related mortality was only 2.4%. Reintervention rates were 10.1% for endovascular and 6.7% for surgical reintervention. Pooled rates of overall survival at 1-, 3-, 5- and 10-year were 91.5%, 84.7%, 77.7% and 56.3%, respectively.

CONCLUSIONS

The significant heterogeneity in the available evidence and absence of consensus reporting standards are important considerations and concern when interpreting the data. Evaluation of the evidence suggests that TEVAR for CTBAD is a safe procedure with low rates of complications. However, the optimal treatment strategy for CTBAD remains debatable and requires further research. Evidence from high-quality registries and clinical trials are required to address these challenges.

Fluid-structure interaction: Insights into biomechanical implications of endograft after thoracic endovascular aortic repair

Thoracic endovascular aortic repair (TEVAR) has developed to be the most effective treatment for aortic diseases. This study aims to evaluate the biomechanical implications of the implanted endograft after TEVAR. We present a novel image-based, patient-specific, fluid-structure computational framework. The geometries of blood, endograft, and aortic wall were reconstructed based on clinical images. Patient-specific measurement data was collected to determine the parameters of the three-element Windkessel. We designed three postoperative scenarios with rigid wall assumption, blood-wall interaction, blood-endograft-wall interplay, respectively, where a two-way fluid-structure interaction (FSI) method was applied to predict the deformation of the composite stent-wall. Computational results were validated with Doppler ultrasound data. Results show that the rigid wall assumption fails to predict the waveforms of blood outflow and energy loss (EL). The complete storage and release process of blood flow energy, which consists of four phases is captured by the FSI method. The endograft implantation would weaken the buffer function of the aorta and reduce mean EL by 19.1%. The closed curve area of wall pressure and aortic volume could indicate the EL caused by the interaction between blood flow and wall deformation, which accounts for 68.8% of the total EL. Both the FSI and endograft have a slight effect on wall shear stress-related-indices. The deformability of the composite stent-wall region is remarkably limited by the endograft. Our results highlight the importance of considering the interaction between blood flow, the implanted endograft, and the aortic wall to acquire physiologically accurate hemodynamics in post-TEVAR computational studies and the deformation of the aortic wall is responsible for the major EL of the blood flow.

Patient-specific simulation of stent-graft deployment in type B aortic dissection: model development and validation

Thoracic endovascular aortic repair (TEVAR) has been accepted as the mainstream treatment for type B aortic dissection, but post-TEVAR biomechanical-related complications are still a major drawback. Unfortunately, the stent-graft (SG) configuration after implantation and biomechanical interactions between the SG and local aorta are usually unknown prior to a TEVAR procedure. The ability to obtain such information via personalised computational simulation would greatly assist clinicians in pre-surgical planning. In this study, a virtual SG deployment simulation framework was developed for the treatment for a complicated aortic dissection case. It incorporates patient-specific anatomical information based on pre-TEVAR CT angiographic images, details of the SG design and the mechanical properties of the stent wire, graft and dissected aorta. Hyperelastic material parameters for the aortic wall were determined based on uniaxial tensile testing performed on aortic tissue samples taken from type B aortic dissection patients. Pre-stress conditions of the aortic wall and the action of blood pressure were also accounted for. The simulated post-TEVAR configuration was compared with follow-up CT scans, demonstrating good agreement with mean deviations of 5.8% in local open area and 4.6 mm in stent strut position. Deployment of the SG increased the maximum principal stress by 24.30 kPa in the narrowed true lumen but reduced the stress by 31.38 kPa in the entry tear region where there was an aneurysmal expansion. Comparisons of simulation results with different levels of model complexity suggested that pre-stress of the aortic wall and blood pressure inside the SG should be included in order to accurately predict the deformation of the deployed SG.

Computational Investigation and Histopathological Validation of Interaction Between Stent Graft and Aorta in Retrograde Type A Dissection After TEVAR in Canine Models

PURPOSE

Retrograde type A dissection (RTAD) after thoracic endovascular aortic repair (TEVAR) has been a major drawback of endovascular treatment. To our knowledge, no studies have simulated and validated aortic injuries caused by stent grafts (SGs) in animal models. Therefore, the aim of this study was to evaluate and quantify the SG-aorta interaction through computational simulations and to investigate the underlying mechanism through histopathological examinations.

METHODS

Two custom-made Fabulous^® (DiNovA Meditech, Hang Zhou, China) SGs were implanted in 2 canine aortas with a 5-mm difference in the distance in landing locations. The aortic geometries were extracted from RTAD and non-RTAD cases. A computational SG model was assembled based on the implanted SG using the software Pro-ENGINEER Wildfire 5.0 (PTC Corporation, Needham, Mass). TEVAR simulations were performed 7 times for each canine model using Abaqus software (Providence, RI, USA), and the maximum aortic stress (MAS) was calculated and compared among the groups. Three months after SG implantation, the canine aortas were harvested, and were examined using hematoxylin and eosin staining and Elastica Van Gieson (EVG) staining to evaluate histopathological changes.

RESULTS

In the computational models for both canines, MAS was observed at the proximal bare stent (PBS) at aortic greater curve. The PBS generated higher stress toward the aortic wall than other SG parts did. Moreover, the MAS was significantly higher in canine No.1 than in canine No.2 (0.415±0.210 versus 0.200±0.160 MPa) (p<0.01). Notably, in canine No.1, an RTAD developed at the MAS segment, and histopathological examinations of the segment showed an intimal flap, a false lumen, elastin changes, and medial necrosis. RTAD was not observed in canine No.2. In both SG-covered aortas, medial necrosis, elastic fiber stretching, and inflammatory infiltration were seen.

CONCLUSION

The characteristic MAS distribution remained at the location where the apex of the PBS interacted with the aortic wall at greater curve. RTAD histopathological examinations showed intimal damage and medial necrosis at the proximal landing zone, at the same MAS location in computational simulations. The in vivo results were consistent with the computational simulations, suggesting the MAS at greater curve may cause RTAD, and the potential application of computational simulation in the mechanism study of RTAD.

Patient-Specific Virtual Stent-Graft Deployment for Type B Aortic Dissection: A Pilot Study of the Impact of Stent-Graft Length

Thoracic endovascular aortic repair (TEVAR) has been accepted as a standard treatment option for complicated type B aortic dissection. Distal stent-graft-induced new entry (SINE) is recognised as one of the main post-TEVAR complications, which can lead to fatal prognosis. Previous retrospective cohort studies suggested that short stent-graft (SG) length (<165 mm) might correlate with increased risk of distal SINE. However, the influence of SG length on changes in local biomechanical conditions before and after TEVAR is unknown. In this paper, we aim to address this issue using a virtual SG deployment simulation model developed for application in type B aortic dissection. Our model incorporates detailed SG design and hyperelastic behaviour of the aortic wall. By making use of patient-specific geometry reconstructed from pre-TEVAR computed tomography angiography (CTA) scan, our model can predict post-TEVAR SG configuration and wall stress. Virtual SG deployment simulations were performed on a patient who underwent TEVAR with a short SG (158 mm in length), mimicking the actual clinical procedure. Further simulations were carried out on the same patient geometry but with different SG lengths (183 mm and 208 mm) in order to evaluate the effect of SG length on changes in local stress in the treated aorta. Comparisons of simulation results for different SG lengths showed the location of maximum stress varied with the SG length. With the short SG (deployed in the patient), the maximum von Mises stress of 238.9 kPa was found on the intimal flap at the distal landing zone where SINE was identified at 3-month follow-up. Increasing the SG length caused the maximum von Mises stress to move away from the distal landing zone where stress values were reduced by approximately 17% with the medium-length SG and by 60% with the long SG. This pilot study demonstrates the potential of using the virtual SG deployment model as a pre-surgical planning tool to help select the most appropriate SG length for individual patients.

Intraoperative Stent-Graft-Induced Aortic Intimal Intussusception During TEVAR for Type B Aortic Dissection

BACKGROUND

Aortic intimal intussusception is well described in the natural progression of type A aortic dissection. Only 3 cases of aortic intimal intussusception were reported to be related to thoracic endovascular aortic repair (TEVAR) for Stanford type B aortic dissection. In our study, we are reporting a rare but potentially fatal complication, the intraoperative stent-graft (SG)-induced aortic intimal intussusception (ISAII); this study reports a series of endovascular repair for ISAII cases. By presenting the ISAII definition, the diagnostic steps to rule out or to identify the condition, and the techniques to resolve it, we intended to raise the awareness of this severe complication, so that physicians can adapt to overcome the complications while performing TEVAR.

MATERIALS AND METHODS

ISAII was defined as the partial or circumferential disruption of the distal intimal flap as an intraoperative complication of endovascular treatment. From January 2014 to June 2020, 1,096 patients underwent TEVAR for Stanford type B aortic dissection at our hospital. Among them, 14 ISAII complications were witnessed. All these patients underwent endovascular repair for ISAII lesions, and their data were extracted for analysis.

RESULTS

The ISAII lesions were classified into 3 types according to their location in different aortic segments: type I, ISAII was limited within the intended SG coverage segment; type II, ISAII occurred after SG introduction or deployment, and the detached intimal flap extended beyond the intended SG coverage segment but did not affect the abdominal aortic visceral branches; type III, ISAII occurred during SG introduction or deployment, and the detached intimal flap descended to the abdominal aortic segment with visceral branches. Our results showed ISAII as a rare complication with an incidence of 1.28% (14/1096), and endovascular repair for all types of ISAII is an effective treatment. With a mean follow-up of 27.36 months (range 5-71 months), all the ISAII lesions were stable, and all the major aortic branches, SGs, and bare stents were patent.

CONCLUSIONS

The management of this potentially devastating intraoperative complication relies on accurate diagnosis and prompt management. Our results suggested that endovascular repair for ISAII is effective and durable for correcting this complication.

GRAPHICAL ABSTRACT

[Formula: see text].

A S-Shaped Association of Distal Oversizing Ratio with Distal Stent-Graft-Induced New Entry Following Thoracic Endovascular Aortic Repair for Stanford B Aortic Dissection

BACKGROUND

This study was performed to evaluate the nonlinear association of the distal oversizing ratio with distal stent-graft-induced new entry (dSINE) following thoracic endovascular aortic repair (TEVAR) for type B aortic dissection (TBAD) and to find the optimal value of the distal oversizing ratio for prevention strategy of dSINE.

METHODS

Total of 177 patients who underwent TEVAR for TBAD from the Registry Of type B aortic dissection with the Utility of STent graft were retrospectively investigated. Patients were stratified into two groups on the median distal oversizing ratio: lower group (≤16%, n = 88) and higher group (>16%, n = 89). The Kaplan-Meier method was used to estimate the cumulative incidence of dSINE. The multivariate Cox proportional hazards model was used to identify the association of the distal oversizing ratio with dSINE. Restricted cubic smoothing spline plots and two-piecewise regression were used to analyze the possible nonlinear association.

RESULTS

Eleven patients developed dSINE (6.21%) during the median follow-up time of 12.37 months (interquartile range, 8.07-18.17 months). An S-shaped association of the distal oversizing ratio with dSINE was identified. When the distal oversizing ratio was ≤40%, the risk of dSINE increased with distal oversizing ratio, and the risk of dSINE was highest when the distal oversizing ratio reached 40% (adjusted HR, 1.09; 95% CI, 1.02-1.17; P = 0.011). A larger distal oversizing ratio over 40% did not generate a greater risk of dSINE (adjusted HR, 0.95; 95% CI, 0.87-1.05; P = 0.455).

CONCLUSIONS

This study substantiated previous findings that the dSINE was associated with the increasing distal oversizing ratio. We also found an S-shaped association between the distal oversizing ratio and dSINE after TEVAR for TBAD. The distal oversizing ratio of 40% can be used for stratified management of patients who underwent TEVAR for TBAD.

Association between aortic arch angulation and bird-beak configuration after thoracic aortic stent graft repair of type B aortic dissection

OBJECTIVES

The goal of this study was to investigate factors favouring the bird-beak configuration after thoracic endovascular aortic repair (TEVAR) for type B aortic dissection.

METHODS

We retrospectively analysed 76 patients with type B aortic dissection who underwent landing zone 1 and 2 TEVAR from December 2015 to January 2018. Preoperative aortic arch geometry (aortic arch length, maximal diameter and angulation), stent graft details and operative details were evaluated. A bird-beak configuration was defined as a ≥5-mm gap between the proximal end of the stent and the aortic wall of the lesser curvature.

RESULTS

Patients were stratified into those with (n = 46) and without (n = 30) a bird-beak configuration. The baseline demographics, dissection chronicity, clinical features and implanted devices were largely similar between the 2 groups. No significant difference was observed in the arch length or maximal arch diameter. However, the mean aortic arch angulation was greater in patients with than without a bird-beak configuration (61.4° vs 51.3°; P < 0.001). No influence of either the stent graft brand or the proximal stent graft type was observed. The multivariable analysis showed that the aortic arch angulation was an independent risk factor for a bird-beak configuration (odds ratio 1.15, 95% confidence interval 1.07-1.24; P < 0.001). A cut-off angle of 59.15° was predictive of a bird-beak configuration (sensitivity 59%; specificity 77%).

CONCLUSIONS

The preoperative aortic arch angulation was an independent predictor of a postoperative bird-beak configuration in patients with type B aortic dissection who underwent TEVAR that involved the aortic arch. An angle of >59.15° may imply a relatively hostile anatomy with a higher risk of a bird-beak configuration.

Genetic aortic disease epidemiology, management principles, and disparities in care

Patients with syndromic and nonsyndromic heritable aortopathies (also known as genetic aortic disease) are a heterogeneous group of patients who present at younger ages with more rapid growth of aortic aneurysms and/or increased frequency of dissections compared with patients with atherosclerotic aortopathies. In this review, we describe the etiology, epidemiology, and appropriate care delivery for these conditions at each stage of management. Within each section, we discuss sex, gender, and race differences and highlight disparities in care and knowledge. We then discuss the role of the vascular team throughout the cycle of care and the evolving inclusion of patient input in research. This understanding is essential to the creation of effective health care policies that support equitable, appropriate, and patient-centered clinical practices.

Clinical Outcomes of Distal Tapered Restrictive Covered Stent Applied in Endovascular Treatment of Aortic Dissection Involving Zone 0

OBJECTIVE

The safety and efficacy of a distal tapered restrictive covered stent (RCS) applied in the endovascular treatment of aortic dissection involving Zone 0 was evaluated.

METHODS

This study retrospectively analysed 43 patients with acute aortic dissection involving Zone 0 who received in situ laser fenestrated thoracic endovascular aortic repair with distal tapered RCS from January 2015 to February 2019. The indication for the distal tapered RCS procedure was an inappropriate distal size of the main stent graft. Technical success, aortic remodelling, and clinical outcomes were evaluated.

RESULTS

Technical success was achieved in all patients. The 30 day post-operative mortality rate was 0%. All patients had complete false lumen thrombosis in the stent coverage segment. True lumen volume increased significantly (p < .001) with an average change of 87.0% ± 34.3%, while false lumen volume decreased significantly (p < .001) with an average change of -71.0% ± 13.5% between baseline and 12 months. During the follow up period (mean 28.7 months, range 12-63 months), no distal stent graft induced new entry (SINE) was observed. The average distance between the distal end of the RCS and the coeliac trunk was 57.5 mm. Two (4.7%) patients had spinal cord ischaemia (SCI) and recovered without permanent paraplegia after undergoing conservative treatment.

CONCLUSION

The distal tapered RCS applied in the endovascular treatment of aortic dissection involving Zone 0 is considered to be a feasible and effective approach along with satisfactory aortic remodelling, a low risk of SINE, and SCI. The favourable results are partly explained by selection. No patients had an entry tear near the coronary artery, nor were the coronary arteries, pericardium, or aortic valve involved at the time of repair.

Pre-fenestration endovascular repair of aortic diseases in patients with zone 2 segment: A single-center experience

OBJECTIVE

The present study aims to analyze the outcomes of three cases of pre-fenestration and branch stent-graft endovascular repair of aortic disease with zone 2 aortic lesions.

METHODS

From August 2017 to June 2018, three patients with zone 2 aortic lesions underwent thoracic endovascular repair with innominate artery, left common carotid artery, and left subclavian artery recannulation using pre-fenestration and branched stent-grafts to preserve the patency of the aortic arch branches.

RESULTS

The technical success rate was 100%. One patient had a proximal type I endoleak with no need for additional treatment. The overall mortality was 0%. All branches were patent. The follow-up period lasted for 2-15 months, with one patient lost to follow-up. There were no conversions to open surgical repair, aortic rupture, paraplegia, or retrograde type A aortic dissection.

CONCLUSION

The use of a pre-fenestration and branch stent-graft for the thoracic endovascular repair of zone 2 aortic lesions is a feasible and effective method for aortic arch branch revascularization. The risk of this surgical procedure is high, requiring significant expertise. The procedure should be conducted only in experienced centers. Durability concerns should be assessed in future studies with long-term follow-up.

Characterization of syndromic, nonsyndromic familial, and sporadic type B aortic dissection

OBJECTIVE

Type B aortic dissection (TBAD) is commonly thought of as a sporadic event. However, an increasing body of data has suggested that genetic factors can influence TBAD. Our aim was to determine the prevalence of heritable TBAD, defined as either syndromic TBAD or nonsyndromic familial TBAD and to detail the natural history and long-term clinical outcomes compared with patients with "sporadic" TBAD without an identified syndrome or family history.

METHODS

The clinical records of 389 patients with TBAD who had presented to a single health care system from 1995 to 2017 were reviewed. A family history was obtained by interview and/or medical record review. Syndromic TBAD was defined as TBAD in patients with Marfan, Loeys-Dietz, or vascular Ehlers-Danlos syndrome. Nonsyndromic familial TBAD was defined as a family history of aortic or arterial aneurysm or dissection and/or sudden death in a first- or second-degree relative in the absence of a known syndrome. Patients with syndromic and nonsyndromic familial TBAD were compared with patients with sporadic TBAD in terms of the comorbid conditions, aortic repair, and mortality.

RESULTS

Of 389 patients (71.2% male) with TBAD, the etiology of TBAD was heritable in 27.9% (9.6% syndromic; 18.3% nonsyndromic familial TBAD) and 72.1% sporadic of the cases. Patients with syndromic and nonsyndromic familial TBAD had been more frequently referred in the chronic phase than were the patients with sporadic TBAD (35.5% vs 44.1% vs 25.8%; P = .014) and had presented at a younger age (40.6 ± 10.9 years vs 55.2 ± 11.3 years vs 62 ± 12.9 years; P < .001) and with lower blood pressure at acute TBAD (systolic, 159.2 ± 21 mm Hg vs 178.9 ± 39.3 mm Hg vs 186.1 ± 38.4, P = .01; diastolic, 84.3 ± 17.3 mm Hg vs 91.4 ± 24.1 mm Hg vs 101.6 ± 22.3 mm Hg, P = .001). Among patients with acute TBAD surviving to discharge from the initial hospitalization, thoracic endovascular aortic repair (TEVAR) had been performed in 115 patients, with no significant differences in TEVAR usage in the three groups. However, those with syndromic and nonsyndromic familial TBAD had had a greater incidence of retrograde aortic dissection after TEVAR (33.3% vs 15% vs 3%; P = .006). They had also required a greater number of arch repairs (30% vs 10.5% vs 3.6%; P < .001) and had died at a younger age (47.7 ± 13.1 years vs 65.7 ± 13.7 years vs 72.8 ± 12.7 years; P < .001). Aortic-related mortality was more common among patients with syndromic TBAD (36.7% vs 12.3% vs 17.6%; P = .016).

CONCLUSIONS

In our single-institutional experience, heritable TBAD accounted for one in four patients with TBAD. Nonsyndromic familial TBAD was twice as common as syndromic TBAD and appeared to share many clinical features. Identifying these patients early in their disease course and personalizing their care might improve their survival.

A multicenter "real-world" study of the valiant NAVION stent graft

BACKGROUND

The aim of the present study was to evaluate early results of thoracic endovascular aortic repair (TEVAR) using the Valiant Navion™ stent graft in a "real-world" scenario.

METHODS

All patients who underwent TEVAR with the Valiant Navion™ endograft between November 2018 and November 2019 were included in this retrospective multicenter study (six European centers). The primary endpoints were technical success, incidence of major adverse events (MAEs), access failure, deployment failure, deployment accuracy, and rate of intraoperative endoleaks (ELs).

RESULTS

One hundred-sixteen patients with varying thoracic aortic diseases were included. Eighteen patients (15.5%) were treated for an off-label condition. The technical success rate was 100%, without any access or deployment failures. The proximal and distal deployment accuracy rates were 99.1% and 97.4%, respectively. There were no intraoperative MAEs, including death. Two (1.7%) type Ib ELs were detected at the first postoperative CTA, all of which were in off-label procedures and related to the short length of the sealing neck. No type III ELs were detected. The median hospitalization time was 8 days (IQR 4-12), including a median intensive care unit stay of 1 day (IQR 1-2). The in-hospital mortality rate was 4.3%. At a median follow-up time of 98 days (IQR 39-187), there were no aortic-related mortalities or new onset of endoleaks.

CONCLUSION

Our initial experience with the Valiant Navion™ endograft in a wide variety of aortic diseases showed safe early outcomes, especially for on-label procedures.