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.

Volumetric analysis of acute uncomplicated type B aortic dissection using an automated deep learning aortic zone segmentation model.

BACKGROUND: Machine learning techniques have shown excellent performance in three-dimensional medical image analysis, but have not been applied to acute uncomplicated type B aortic dissection (auTBAD) using Society for Vascular Surgery (SVS) and Society of Thoracic Surgeons (STS)-defined aortic zones. The purpose of this study was to establish a trained, automatic machine learning aortic zone segmentation model to facilitate performance of an aortic zone volumetric comparison between patients with auTBAD based on the rate of aortic growth. METHODS: Patients with auTBAD and serial imaging were identified. For each patient, imaging characteristics from two computed tomography (CT) scans were analyzed: (1) the baseline CT angiography (CTA) at the index admission and (2) either the most recent surveillance CTA or the most recent CTA before an aortic intervention. Patients were stratified into two comparative groups based on aortic growth: rapid growth (diameter increase of ≥5 mm/year) and no or slow growth (diameter increase of <5 mm/year). Deidentified images were imported into an open source software package for medical image analysis and images were annotated based on SVS/STS criteria for aortic zones. Our model was trained using four-fold cross-validation. The segmentation output was used to calculate aortic zone volumes from each imaging study. RESULTS: Of 59 patients identified for inclusion, rapid growth was observed in 33 patients (56%) and no or slow growth was observed in 26 patients (44%). There were no differences in baseline demographics, comorbidities, admission mean arterial pressure, number of discharge antihypertensives, or high-risk imaging characteristics between groups (P > .05 for all). Median duration between baseline and interval CT was 1.07 years (interquartile range [IQR], 0.38-2.57). Postdischarge aortic intervention was performed in 13 patients (22%) at a mean of 1.5 ± 1.2 years, with no difference between the groups (P > .05). Among all patients, the largest relative percent increases in zone volumes over time were found in zone 4 (13.9%; IQR, -6.82 to 35.1) and zone 5 (13.4%; IQR, -7.78 to 37.9). There were no differences in baseline zone volumes between groups (P > .05 for all). The average Dice coefficient, a performance measure of the model output, was 0.73. Performance was best in zone 5 (0.84) and zone 9 (0.91). CONCLUSIONS: We describe an automatic deep learning segmentation model incorporating SVS-defined aortic zones. The open source, trained model demonstrates concordance to the manually segmented aortas with the strongest performance in zones 5 and 9, providing a framework for further clinical applications. In our limited sample, there were no differences in baseline aortic zone volumes between patients with rapid growth and patients with no or slow growth.

Outcomes of post-implantation syndrome after endovascular repair for Stanford type B aortic dissection.

OBJECTIVE: The aim of this study was to investigate the correlation between post-implantation syndrome (PIS) and long-term prognosis in patients with Stanford type B aortic dissection (TBAD) undergoing thoracic endovascular aortic repair (TEVAR). METHODS: This retrospective study included 547 consecutive patients diagnosed with TBAD who underwent TEVAR at our institution between January 2014 and December 2019. Patients were categorized into two groups: the PIS group (patients with post-TEVAR PIS) and the non-PIS group (patients without post-TEVAR PIS). In-hospital and follow-up data were analyzed. RESULTS: The incidence of PIS was 28.9% (158/547 patients). No baseline differences were observed between the PIS (n = 158) and the non-PIS (n = 389) groups. The proportion of emergency surgery in the PIS group was higher than that in the non-PIS group (44.9% vs 26.0%; P < .001), the operation time was longer (median, 65.0; interquartile range [IQR], 56.0-75.0 minutes vs 56.0; IQR, 45.0-66.0 minutes; P < .001), the volume of contrast medium used (median, 65.0; IQR, 56.0-75.0 mL vs 56.0; IQR, 45.0-66.0 mL; P < .001), and the average number of trunk stents (1.85 ± 0.4 vs 1.34 ± 0.5 pieces; P < .001) and branch stents (0.7 ± 0.7 vs 0.2 ± 0.5 pieces; P < .001) used were more in the PIS group than in the non-PIS group. The incidence of supra-aortic branch procedures was higher in the PIS group than in the non-PIS group. There was no significant difference in device-related complications (DRCs) or 30-day mortality between the two groups (2.5% vs 4.4%; P = .442 and 1.3% vs 1.3%; P = .688, respectively). Univariate and multivariable logistic regression analysis showed that emergency surgery, number of trunk stents >1, operation time >58.5 minutes, and contrast medium volume >75 mL were risk factors for PIS, and the odds ratios of emergency operation, number of trunk stents >1 piece, operation time >58.5 minutes, and contrast medium volume >75 mL were 2.526 (95% confidence interval [CI], 1.530-4.173), 4.651 (95% CI, 2.838-7.624), 3.577 (95% CI, 2.201-5.815), and 7.356 (95% CI, 4.111-13.160), respectively. Follow-up was completed in 98.5% (532/540) of the patients, with a median follow-up of 67 months (IQR, 50-86 months). There was no significant difference in survival between the PIS and non-PIS groups (12.4% vs 10.3%; P = .476) during follow-up. The incidences of DRCs (7.8% vs 11.6%; P = .200) and aortic false lumen thrombosis (75.8% vs 79.2%; P = .399) were comparable between the PIS and non-PIS groups. Univariate logistic regression analysis showed that PIS had no effect on long-term follow-up mortality, DRCs, entry flow, or aortic false lumen thrombosis rate. CONCLUSIONS: PIS is relatively common after TEVAR and emergency surgery; number of trunk stents >1, operation time >58.5 minutes, and contrast medium volume >75 mL are of high predictive value for the assessment of PIS after TEVAR. However, PIS had little effect on early and late postoperative mortality or DRCs.

Early three-dimensional growth in uncomplicated type B aortic dissection is associated with long-term outcomes.

OBJECTIVE: Late adverse events (LAEs) are common among initially uncomplicated type B aortic dissection (uTBAD); however, identifying those patients at highest risk of LAEs remains a significant challenge. Early false lumen (FL) growth has been suggested to increase risk, but confident determination of growth is often hampered by error in two-dimensional clinical measurements. Semi-automated three-dimensional (3D) mapping of aortic growth, such as by vascular deformation mapping (VDM), can potentially overcome this limitation using computed tomography angiograms (CTA). We hypothesized that FL growth in the early pre-dissection phase by VDM can accurately predict LAEs. METHODS: We performed a two-center retrospective study of patients with uTBAD, with paired CTAs in the acute (1-14 days) and subacute/early chronic (1-6 months) periods. VDM analysis was used to map 3D growth. Standard clinical CT measures (ie, aortic diameters, tear characteristics) were also collected. Multivariate analysis was conducted using a decision tree and Cox proportional hazards model. LAEs were defined as aneurysmal FL (>55 mm); rapid growth (>5 mm within 6 months); aorta-specific mortality, rupture, or re-dissection. RESULTS: A total of 107 (69% male) patients with uTBAD initially met inclusion criteria with a median follow-up of 7.3 years (interquartile range [IQR], 4.7-9.9 years). LAEs occurred in 72 patients (67%) at 2.5 years (IQR, 0.7-4.8 years) after the initial event. A multivariate decision tree model identified VDM growth (>2.1 mm) and baseline diameter (>42.7 mm) as optimal predictors of LAEs (area under the receiver operating characteristic curve = 0.94), achieving an 87% accuracy (sensitivity of 93%, specificity of 76%) after leave-one-out validation. Guideline reported high-risk features were not significantly different between groups. CONCLUSIONS: Early growth of the FL in uTBAD was the best tested indicator for LAEs and improves upon the current gold-standard of baseline diameter in selecting patients for early prophylactic thoracic endovascular aortic repair.

Diagnostic potential of soluble ST2 and D-dimer for Stanford Type B aortic dissection and intramural aortic hematoma.

OBJECTIVE: Type B aortic dissection (TBAD) and intramural aortic hematoma (IMH) are common manifestations of Acute Aortic Syndrome (AAS), exhibiting overlapping clinical features. The timely and accurate diagnosis and differentiation between TBAD and IMH are critical for appropriate management. Tumorigenicity 2 (sST2) and D-dimer have been shown to elevate levels in both TBAD and IMH, making them valuable as "rule-out" markers. Hence, we aimed to assess the diagnostic utility of sST2 and D-dimer in distinguishing TBAD from IMH. METHODS: In this retrospective study, we analyzed serum levels of sST2 and D-dimer in 182 AAS patients, comprising 90 TBAD cases, 92 IMH cases, and 90 non-AAS cases. Serial measurements were taken at 1 h, 6 h, 12 h, 24 h, and 72 h post-admission. Comparative analyses were conducted between TBAD and non-AAS cases, IMH and non-AAS cases, and TBAD and IMH cases. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic accuracy of sST2 and D-dimer in identifying TBAD or IMH cases. RESULTS: Both TBAD and IMH patients displayed elevated levels of sST2 and D-dimer compared to non-AAS cases. Notably, sST2 levels were significantly higher in TBAD patients than in IMH patients, whereas D-dimer levels exhibited moderate differences. TBAD patients tended to exhibit elevated levels of either sST2 or D-dimer, with a modest correlation between the two (Pearson correlation coefficient = 0.3614). In contrast, IMH patients showed elevations in both markers, with a positive correlation between them (Pearson correlation coefficient = 0.6814). The ROC analysis revealed that both sST2 (AUC, 0.657; 95 % CI, 0.552-0.753; cutoff value, 27.54 ng/ml) and D-dimer (AUC, 0.695; 95 % CI, 0.591-0.787, cutoff value, 1.215 ng/ml) demonstrated favorable diagnostic performance for TBAD. sST2 exhibited a sensitivity of 80.92 % and a specificity of 75.00 %, while D-dimer showed a sensitivity of 80.92 % and a specificity of 75.00 %. For the diagnosis of IMH, the combined assessment of sST2 and D-dimer (AUC, 0.674; 95 % CI, 0.599-0.768; sensitivity, 69.20 %; specificity, 80.00 %) proved effective. CONCLUSIONS: Our results indicate that both sST2 and D-dimer show diagnostic potential for TBAD. Elevated levels of either serve as an indicator of TBAD onset. However, concurrent elevation of both markers seems to be indicative of IMH. The combination of increased sST2 and D-dimer levels demonstrates strong diagnostic performance in identifying IMH cases.

Multilayer Flow Modulator Stent for Aortic Pathology: A Meta-Analysis and Additional Data from a Single-Centre Retrospective Cohort.

Background: Thoracoabdominal aneurysms and aortic dissections are a challenge for vascular surgeons. Open surgery, fenestrated or branched endograft, and the chimney technique are not possible in some patients, because of comorbidities or anatomical restrictions. However, the multilayer flow modulator (MFM) can be implanted in some of these patients. In this systematic review, we will describe the experience with the multilayer stent. To augment the limited number of studies available, we will include a cohort of patients from our hospital. Methods: We retrieved data on all consecutive patients treated using the MFM between May 2013 and August 2020. This included patients with type B dissections and thoracoabdominal or thoracic aneurysms who were unfit for open surgery. The systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We included all the studies that used the MFM in the aortic segment. Single-arm meta-analyses were performed using OpenMeta (Brown University, Providence, RI, USA). Results: A total of 37 patients were treated in our hospital during the study period. The technical success was 97.3% and the 30-day mortality was 5.4%. In 40.5% of the included patients, the instructions for use were not followed. Off-label implantation was associated with a higher aneurysm-related mortality. A total of 12 studies were included in the meta-analysis and the technical success was 97.8%. In 68.5%, the aneurysm sack or false lumen remained perfused, 97% of all the covered side branches remained patent. After a follow-up period of 1 year, five patients in the meta-analysis presented with a ruptured aneurysm. Conclusions: The overall quality of evidence is poor because long-term results are lacking, patients are frequently lost during follow-up and all the studies were non-comparative. Our retrospective study suggests a relatively low incidence of perioperative complications, although there was a high incidence of persistent perfusion in the aneurysm sac (102 of 149 patients). The risk of rupture at the 1-year follow-up was 2.1%.

Incidence, Predictors, and Implications of Secondary Aortic Intervention Following Thoracic Endovascular Aortic Repair for Type B Dissection.

BACKGROUND: Secondary aortic intervention (SAI) following thoracic endovascular aortic repair (TEVAR) is not uncommon. However, a satisfactory management system has not been established for these patients. We aimed to report our single-center experience with SAI after prior TEVAR for type B aortic dissection (TBAD). METHODS: From January 2010 to May 2017, 860 eligible patients with TBAD underwent TEVAR. One hundred seven (12.4%) patients required SAI, either endovascularly (n=76) or surgically (n=31). The main indications for SAI were entry flow (n=58 [54.2%]), aneurysm expansion of the proximal or remote aorta (n=26 [24.3%]), retrograde type A aortic dissection (n=11 [10.3%]), distal stent-graft-induced new entry tear (n=6 [5.6%]), and stent migration (n=4 [3.7%]). The Kaplan-Meier curves were generated to determine the degree of freedom from SAI and the prognosis. Cox proportional hazards were used to screen for risk factors for SAI and poor prognosis. RESULTS: The overall 30-day mortality rate after SAI was 4.7% (n=5): endovascular (n=2 [2.6%]) vs open surgery (n=3 [9.7%]; p=0.145). The cumulative survival rates with or without SAI were 86.3%±3.6% vs 95.7%±0.8% at 3 years and 82.0%±4.2% vs 92.2%±1.1% at 5 years, respectively (log-rank p<0.001). Although no significant difference in survival was observed, the incidence of SAI was significantly greater in patients who underwent TEVAR during the chronic phase (acute [11.6%] vs subacute [9.6%] vs chronic [27.8]; p<0.001). Multivariate regression analysis revealed that prior TEVAR in the chronic phase (hazard ratio [HR]=1.73, 95% confidence interval [CI]=1.03-2.90; p=0.039), maximum aortic diameter (HR=1.05, 95% CI=1.04-1.07; p<0.001), and arch involvement (HR=1.48, 95% CI=1.01-2.18; p=0.048) were predictors of the incidence of SAI. In addition, the maximum aortic diameter was demonstrated to be the only risk factor for prognosis after adjusting for confounding factors. CONCLUSIONS: Thoracic endovascular aortic repair for chronic TBAD patients should be reconsidered. Open surgery is preferable for those with proximal progression, whereas endovascular treatment is more suitable for distal lesions. Close surveillance and timely reintervention after TEVAR, whether via endovascular techniques or open surgery, are necessary to prevent devastating complications. CLINICAL IMPACT: The management of patients with type B aortic dissection (TBAD) after thoracic endovascular aortic repair (TEVAR) is challenging. We summarized our single-center experience regarding secondary aortic intervention after TEVAR for TBAD. We found that TEVAR for chronic TBAD patients should be carefully evaulated, and open surgery is recommended for those with proximal progession, while endovascular treatment is more preferable for distal lesions.

Optimal Timing of Pre-emptive Thoracic Endovascular Aortic Repair in Uncomplicated Type B Aortic Dissection: A Network Meta-Analysis.

BACKGROUND: This network meta-analysis compares outcomes of optimal medical therapy (OMT) and pre-emptive thoracic endovascular aortic repair (TEVAR) for uncomplicated type B aortic dissection at different phases of chronicity. METHODS: MEDLINE and EMBASE were searched through November 2023. Pooled short-term outcomes (short-term mortality, perioperative complications) and long-term outcomes (all-cause mortality, aortic-related mortality, aortic re-intervention rates) were calculated. RESULTS: Systematic review identified 17 studies (2 randomized controlled trials, 3 propensity score matching, and 2 inverse probability weighting). Subacute-phase intervention had lower short-term mortality than the acute-phase (hazard ratio [HR] [95% confidence interval [CI]]=0.60 [0.38-0.94], p=0.027). No significant differences were observed in aortic rupture and paraplegia. Acute-phase TEVAR had a higher stroke incidence than subacute-phase intervention (HR [95% CI]=2.63 [1.36-5.09], p=0.042), chronic (HR [95% CI]=2.5 [1.03-6.2], p=0.043), and OMT (HR [95% CI]=1.57 [1.12-2.18], p=0.008). Acute-phase TEVAR had higher long-term all-cause mortality than subacute-phase intervention (HR [95% CI]=1.34 [1.03-1.74], p=0.03). Optimal medical therapy had elevated long-term all-cause mortality compared with subacute-phase TEVAR (HR [95% CI]=1.67 [1.25-2.33], p<0.001) and increased long-term aortic-related mortality vs acute-phase (HR [95% CI]=2.08 [1.31-3.31], p=0.002) and subacute-phase (HR [95% CI]=2.6 [1.62-4.18], p<0.01) interventions. No significant differences were observed in aortic re-intervention rates. CONCLUSIONS: Pre-emptive TEVAR may offer lower all-cause mortality and aortic-related mortality than OMT. Considering lower short-term mortality, perioperative stroke rate, and long-term mortality, our findings support pre-emptive TEVAR during the subacute phase. CLINICAL IMPACT: The optimal timing of pre-emptive thoracic endovascular aortic repair (TEVAR) for uncomplicated type B aortic dissection remains uncertain. This network meta-analysis suggests that the subacute phase (14-90 days from symptom onset) emerges as the optimal timing for pre-emptive TEVAR. This window is associated with lower rates of short-term complications and higher long-term survival rates compared with alternative strategies.

Six Years' Experience With a Novel Dissection-Specific Stent-Graft to Prevent Distal Stent-Graft-Induced New Entry.

INTRODUCTION: Thoracic endovascular aortic repair (TEVAR) in chronic dissection is associated with a risk for distal stent-graft-induced new entry (dSINE) in up to a quarter of cases. We assess the mid-term outcome of a novel dissection-specific stent-graft (DSSG), which is a custom-made device based on the Cook Alpha platform, with a modified graft design and a distal endovascular elephant trunk without any supporting stent to reduce the radial force on the dissection membrane at the distal landing zone. METHODS: A retrospective single-center study of chronic dissection patients at high risk of dSINE who received an elective endovascular repair with DSSG from January 2017 to June 2023. The primary outcome is Kaplan-Meier (KM) estimated freedom from dSINE during follow-up. Secondary outcomes included technical success, aortic remodeling, and anatomical evaluation of the distal landing zone in cases with dSINE during follow-up versus those without. RESULTS: Thirty patients (24 males) with a median age of 66 years [range=31-78] underwent elective TEVAR with the DSSG. The majority, n=27 (90%), had previous aortic repair; 7 (23%) had established connective tissue disease, and 6 (20%) had established dSINE after previous stent-graft implantation as an indication for TEVAR. Technical success was achieved in n=29 (97%). Median follow-up was 38.5 months (4.3-76.4), and KM estimated freedom from dSINE at 1 and 3 years was 95.6% (SE 0.043) and 89% (SE 0.081), respectively Four cases developed dSINE during follow-up. The median distance from the distal stent-graft to the coeliac trunk was 74mm (range=18-123) in the dSINE group versus 26mm (range=0-74) in the non-dSINE group (p=0.049). Median proximal tangential aortic angulation in the distal landing zone was 38.5° (range=26°-50°) in the dSINE group compared to 21° (range=3-61°) in the non-dSINE group (p=0.052). CONCLUSIONS: The Use of a novel DSSG with low radial force for TEVAR in the setting of chronic dissection is safe and feasible, with remodeling outcomes comparable with standard TEVAR. The reduced distal radial force in the DSSG does not eliminate the risk for dSINE over time, with new entries occurring, particularly in cases where the distal landing zone is in a tortuous aortic segment and not close to the coeliac trunk. CLINICAL IMPACT: Using the novel dissection-specific stent-graft with reduced radial force is safe and feasible but does not completely eliminate the risk of dSINE occurring over time. The exact positioning of the distal stent-graft in a straight aortic segment, close to the coeliac trunk, may be of importance to further mitigate the risk.

Preclinical Evaluation of a Modular Inner-Branched Stent Graft to Reconstruct the Left Subclavian Artery in Thoracic Endovascular Aortic Repair: Experimental Study in Pigs.

PURPOSE: In approximate 40% of thoracic endovascular aortic repair (TEVAR) procedures, the left subclavian artery (LSA) needs to be covered to obtain sufficient proximal sealing zone. To preserve the LSA during the TEVAR for type B aortic dissection (TBAD) adjacent to LSA, our team designed a modular single inner-branched stent graft. This study was performed to evaluate the safety and feasibility of deploying a modular single inner-branched stent graft in a porcine model. MATERIALS AND METHODS: Modular inner-branched stent grafts were implanted in 14 pigs via right femoral and right carotid arterial access. Computed tomography angiography (CTA) and angiography were performed in all pigs to appraise the morphological characteristics of the stent grafts at the end of follow-up. The pigs were then euthanized, and tissues were collected for gross and histological examination. RESULTS: The technical success rate was 100% (14/14). One pig suddenly died 5 hours after operation, and 1 pig died after completing the follow-up CTA. During the follow-up period, all surviving pigs showed good mental state, normal diets and activities. Computed tomography angiography examinations showed that all stent grafts were intact without fracture. All bridging covered stents were patent. Angiography showed that the position, shape, and adhesion of the stent grafts were good, and no obvious endoleaks were found. Histological examination showed that the biocompatibility of the stent grafts was good. CONCLUSIONS: This study's outcomes demonstrate that it is safe and feasible to deploy a modular single inner-branched stent graft in a porcine model. CLINICAL IMPACT: This device is the first modular device designed to treat TBAD adjacent to LSA in China. This device is a modular two-component system consisting of a thoracic aortic stent graft with a retrograde inner branch and a bridging covered stent. The modular design and the retrograde inner branch are the two important innovations of this device. Theoretically, the device could make it easier and safer for clinicians to treat TBAD adjacent to the LSA.

Radiomics-Based Risk Assessment Correlates With Outcomes in Patients With Acute Type B Aortic Dissection Undergoing Thoracic Endovascular Repair.

OBJECTIVES: Our study aimed to investigate the correlations between radiomics-based assessment and outcomes, including positive aortic remodeling (PAR), reintervention for dissection at 1 year, and overall survival, in patients with Type B aortic dissection (TBAD) who underwent thoracic endovascular aortic repair (TEVAR). METHODS: This was a single-center, retrospective, cohort study. The cohort comprised 104 patients who had undergone TEVAR of TBAD in our institution between January 2010 and October 2022. We segmented preoperative computed tomography (CT) images of the patients' descending aorta regions, then extracted a comprehensive set of radiomic features, including first-order features, shape features (2D and 3D), gray-level co-occurrence matrix (GLCM), gray-level size zone matrix, gray-level run length matrix, gray-level dependence matrix, neighborhood gray-tone difference matrix, from the regions of interest. Next, we selected radiomics features associated with total descending aorta positive aortic remodeling (TDA-PAR) and reintervention by least absolute shrinkage and selection operator (LASSO) regression and features associated with survival by LASSO-Cox regression. This enabled us to calculate radiomics-based risk scores for each patient. We then allocated the patients to high and low radiomics-based risk groups, the cutoff being the median score. We used 3 different models to validate the radiomics-based risk scores. RESULTS: The patients' baseline characteristics did not differ between those who achieved TDA-PAR and those who did not. The radiomics-based risk scores were significantly and independently associated with all 3 outcomes. As to the impact of specific radiomics features, we found that GLSZM_SmallAreaLowGrayLevelEmphasis and shape_Maximum2DDiameterColumn had positive impacts on both reintervention and survival outcomes, whereas GLCM_Idmn positively affected survival but negatively affected reintervention. We found that radiomics-based risk for TDA-PAR correlated most significantly with zone 6 PAR. CONCLUSIONS: Radiomics-based risk scores were significantly associated with the outcomes of TDA-PAR, reintervention, and overall survival. Radiomics has the potential to make significant contributions to prediction of outcomes in patients with TBAD undergoing TEVAR. CLINICAL IMPACT: In this study of 104 patients with Type B aortic dissection, we demonstrated associations between radiomics-based risk and postoperative outcomes, including total descending aorta positive aortic remodeling, reintervention and survival. These findings highlight radiomics' potential as a tool for risk stratification and prognostication in acute Type B aortic dissection management.

Midterm Outcomes of Multicenter Castor Single-Branch Stent Graft Use in the Treatment of Thoracic Aortic Diseases.

PURPOSE: The aim of this study was to evaluate the midterm efficacy and safety of a single-branch Castor stent graft in the treatment of thoracic aortic disease. MATERIALS AND METHODS: Clinical data of 106 patients with thoracic aortic disease treated with Castor single-branch stent graft at 3 centers were collected between May 2018 and June 2023. The indicators included technical success, stent-related complication, reintervention, retrograde dissection, endoleak, distal stent graft-induced entry (dSINE), branch patency, and mortality. The outcomes of the Castor stent graft for multibranch reconstruction above the arch was also analyzed. RESULTS: The technical success was 98.1% (104/106), while the surgical success was 93.4% (99/106). The reintervention was 2.8% (3/106), consisting of a case of retrograde type A dissection, an endoleak, and a dSINE. The retrograde dissection was 1.9% (2/106), while type I endoleak was 1.9% (2/106). The new dSINE was 2.8% (3/106), and the branch patency rate was 100%. The mortality was 1.9% (2/106). The mean follow-up time was 29.1±17.7 months. The 2-year post-surgery cumulative survival rate was 91.0%±3.1%, while the cumulative branch patency rate was 96.2%±2.2%. In addition, the cumulative freedom from stent-related reintervention rate was 93.2%±2.8%. A comparison showed no significant difference in the stent-related complication, branch patency, endoleak, reintervention, and mortality when the proximal end of the Castor stent graft was anchored to zones 1 or 2 of the aorta. CONCLUSION: Castor single-branch stent graft showed favorable early and midterm outcomes in the treatment of thoracic aortic disease. In addition, it was feasible to combine Castor stent graft with other advanced techniques for multibranch aortic arch reconstruction. CLINICAL IMPACT: The Castor single-branch stent graft was approval by the Chinese Food and Drug Administration in 2017. However, there were few studies on the mid-term outcomes for thoracic aortic disease after launching, which mainly focused on small single-center retrospective study. In the study, we assessed the mid-term outcomes of Castor stent graft through multi-center cases, Castor stent graft combined with other advanced techniques (such as fenestration and hybrid) for multi-branch reconstruction of aortic arch were also conducted. We found Castor single-branch stent graft showed favorable early and mid-term outcomes in the treatment of thoracic aortic disease. Additionally, it was feasible to combine Castor stent graft with other advanced technique for multi-branch aortic arch reconstruction. As an off-the-shelf branched stent graft with a wide range of models, it could be also used in most emergent situation. The Castor stent graft was expected to become more widely used in the future.

Development and Validation of a User Friendly Morphology Grading System (PATENT) Predicting Aortic Remodelling After Thoracic Endovascular Aortic Repair in High Risk Uncomplicated Type B Aortic Dissection.

OBJECTIVE: This study aimed to create a morphology grading system, solely based on 2D images from computed tomography angiography, to predict negative aortic remodelling (NAR) for patients with high risk uncomplicated type B aortic dissection (TBAD) after thoracic endovascular aortic repair (TEVAR). METHODS: This single centre retrospective cohort study extracted and analysed consecutive patients diagnosed with high risk uncomplicated TBAD. Negative aortic remodelling was defined as an increase in the false lumen or total aortic diameter, or decrease in the true lumen diameter. The multivariable Cox regression model identified risk factors and a prediction model was created for two year freedom from NAR. A three category grading system, in which patients were classified into low, medium, and high risk groups, was further developed and internally validated. RESULTS: Of 351 patients included, 99 (28%) developed NAR. The median age was 52 years (interquartile range 45, 62 years) and 56 (16%) were female. The rate of two year freedom from NAR was 71% (95% CI 65 - 77%). After the multivariable Cox regression analysis, Patent false lumen, Aberrant right subclavian artery, Taper ratio, abdominal circumferential Extent, coeliac artery or reNal artery involved, and four channel dissection (Three false lumens) remained independent predictors and were included in the PATENT grading system. The risk score was statistically significantly associated with NAR (HR 1.21; 95% CI 1.14 - 1.29; p < .001). The medium and high risk groups demonstrated a higher rate of NAR (medium risk, HR 2.82; 95% CI 1.57 - 5.01; p = .001; high risk, HR 4.39; 95% CI 2.58 - 7.48; p < .001). The grading system was characterised by robust discrimination with Harrell's C index of 0.68 (95% CI 0.63 - 0.75). CONCLUSION: The PATENT grading system was characterised by good discrimination and calibration, which may serve as a clinician friendly tool to aid risk stratification for TBAD patients after TEVAR.

Management and outcomes of aortic dissection type B in late pregnancy: A retrospective case series.

OBJECTIVE: Pregnancy complicated with type B aortic dissection is a rare but devastating condition. Guidelines for managing this condition are lacking. We present our observation and experiences in managing five pregnant women with complicated type B aortic dissection in the second or third trimesters, aiming to gain insights that can aid in proposing an appropriate management strategy. DESIGN: A retrospective study. SETTING: Zhongnan Hospital of Wuhan University. POPULATION: Pregnant women with complicated type B aortic dissection. METHODS: Clinical data of five pregnant women with complicated type B aortic dissection admitted to Zhongnan Hospital of Wuhan University from January 2022 to June 2023 were collected. The clinical characteristics, treatment strategies, and corresponding maternal and infant outcomes were retrospectively analysed. MAIN OUTCOME MEASURES: Survival of mothers and foetuses. RESULTS: All five study participants were diagnosed with complicated type B aortic dissection by computed tomography angiography (CTA). The range of gestational weeks at admission was 27 weeks + 3 days to 36 weeks + 6 days. The first patient, planning a caesarean section (C-section) followed by thoracic endovascular aortic repair (TEVAR), died of aortic dissection rupture during C-section. Her neonate was successfully rescued. In contrast, the remaining four patients who underwent TEVAR first survived. Among them, three patients underwent single-stage aortic repair and delivery, while one patient received C-section 31 days after TEVAR. Three preterm live births were recorded among these surviving mothers. Neonatal death occurred in one case with a gestational age of 29 weeks + 5 days, who had foetal distress before surgery. During the follow-up period of up to 3 months, no maternal or infant death occurred. No device-related or systemic complications were observed in the surviving mothers after discharge. Routine physical examinations of the four live births showed no abnormalities. CONCLUSIONS: For pregnant women with thoracic back pain and high suspicion of aortic dissection, CTA should be conducted promptly to prevent missed or delayed diagnosis. Maternal survival should be prioritised over foetal outcome once diagnosed. TEVAR was demonstrated to be safe and feasible for such patients. For women with complicated type B aortic dissection in late pregnancy, TEVAR followed by C-section may be a promising treatment strategy.

Systemic immune-inflammation index predicts the clinical outcomes in patients with acute uncomplicated type-B aortic dissection undergoing optimal medical therapy.

BACKGROUND: Optimal medical therapy (OMT) for uncomplicated type B aortic dissection (uTBAD) provides excellent short-term outcomes during follow up; however, its long-term therapeutic effectiveness is unsatisfactory. This study evaluated the predictive value of systemic immune-inflammation index (SII) for adverse events among patients with acute uTBAD undergoing OMT. METHODS: We performed a retrospective analysis of a prospectively maintained database between 2013 and 2020. The primary end point in this study was composite outcomes including aortic intervention, all-cause mortality, retrograde type A aortic dissection (rTAAD) and aortic diameter growth > 5 mm. The patients were divided into high and low SII groups according to the optimal cut-off value of SII as determined using the receiver operating characteristic curve. Cox proportional hazards models were constructed to estimate the hazards ratios and identify the predictors of composite outcomes. RESULTS: A total of 124 patients with acute uTBAD who underwent OMT were enrolled. One patient died during hospitalisation. At the end of a mean follow-up duration of 51 ± 23 months, 53 (43.1%) patients experienced composite outcomes, 15 patients (12.2%) died, 31 (25.2%) underwent aortic intervention, 21 (17.1%) exhibited diameter growth of > 5 mm, and 2 developed rTAAD. The patients were divided into low SII group (n = 78, 62.9%) and high SII group (n = 46, 37.1%) as per the optimal cut-off SII value of 1449. The incidence of composite outcomes in high SII group was significantly higher than that in low SII (28 [60.9%] vs. 26[33.3%], p < 0.01). Patients with high SII demonstrated significantly higher mortality rate than those with a low SII (11 [23.9%] vs. 5 [6.4%], respectively; p < 0.01). In addition, the high SII group had significantly higher rate of aortic-related reinterventions than the low SII group (16 [34.8%] vs. 15 [19.2%], p = 0.03). Multivariable Cox analyses showed that a high SII score was independently associated with composite outcomes rate (hazard ratio, 2.15; 95% confidence interval, 1.22-3.78; p < 0.01). CONCLUSIONS: The long-term therapeutic effectiveness of OMT alone in patients with acute uTBAD is unsatisfactory. An SII > 1449 at the time of diagnosis is an independent predictor of OMT failure.

Clinical comparative analysis of 3D printing-assisted extracorporeal pre-fenestration and Castor integrated branch stent techniques in treating type B aortic dissections with inadequate proximal landing zones.

BACKGROUND: This study aims to compare the clinical effects of two distinct surgical approaches, namely 3D printing-assisted extracorporeal pre-fenestration and Castor integrated branch stent techniques, in treating patients with Stanford type B aortic dissections (TBAD) characterized by inadequate proximal landing zones. METHODS: A retrospective analysis was conducted on 84 patients with type B aortic dissection (TBAD) who underwent thoracic endovascular aortic repair (TEVAR) with left subclavian artery (LSA) reconstruction at our center from January 2022 to July 2023. Based on the different surgical approaches, the patients were divided into two groups: the group assisted by 3D printing for extracorporeal pre-fenestration (n = 44) and the group using the castor integrated branch stent (n = 40). Clinical indicators: including general patient information, operative time, surgical success rate, intraoperative and postoperative complication rates, re-intervention rate, and mortality, as well as postoperative aortic remodeling, were compared between the two groups. The endpoint of this study is the post-TEVAR mortality rate in patients. RESULTS: The surgical success rate and device deployment success rate were 100% in both groups, with no statistically significant difference (P > 0.05). However, the group assisted by 3D printing for extracorporeal pre-fenestration had a significantly longer operative time (184.20 ± 54.857 min) compared to the group using the castor integrated branch stent (152.75 ± 33.068 min), with a statistically significant difference (t = 3.215, p = 0.002, P < 0.05). Moreover, the incidence of postoperative cerebral infarction and beak sign was significantly lower in the group assisted by 3D printing for extracorporeal pre-fenestration compared to the castor-integrated branch stent group, demonstrating statistical significance. There were no significant differences between the two groups in terms of other postoperative complication rates and aortic remodeling (P > 0.05). Notably, computed tomography angiography images revealed the expansion of the vascular true lumen and the reduction of the false lumen at three specified levels of the thoracic aorta. The follow-up duration did not show any statistically significant difference between the two groups (10.59 ± 4.52 vs. 9.08 ± 4.35 months, t = 1.561, p = 0.122 > 0.05). Throughout the follow-up period, neither group experienced new endoleaks, spinal cord injuries, nor limb ischemia. In the castor-integrated branch stent group, one patient developed a new distal dissection, prompting further follow-up. Additionally, there was one case of mortality due to COVID-19 in each group. There were no statistically significant differences between the two groups in terms of re-intervention rate and survival rate (P > 0.05). CONCLUSION: Both 3D printing-assisted extracorporeal pre-fenestration TEVAR and castor-integrated branch stent techniques demonstrate good safety and efficacy in treating Stanford type B aortic dissection with inadequate proximal anchoring. The 3D printing-assisted extracorporeal pre-fenestration TEVAR technique has a lower incidence of postoperative cerebral infarction and beak sign, while the castor-integrated branch stent technique has advantages in operative time.

Long-term results of etiology-based thoracic endovascular aortic repair: a single-center experience.

The use of thoracic endovascular aortic repair (TEVAR) for thoracic aortic aneurysm (TAA) and Stanford type B aortic dissection (TBAD) has been increasing; however, in terms of etiology, the differences of long term after TEVAR outcomes remain unexplored. Thus, we investigated etiology-specific long-term results of TEVAR for TAA and TBAD. A total of 421 TEVAR procedures were performed at our institution from July 2007 to December 2021; 249 TAA cases and 172 TBAD cases were included. Traumatic aortic dissection and aortic injury cases were excluded. The mean observation duration was 5.7 years. The overall 30-day mortality rate was 1.4% (n = 6), with 1.2% (n = 3) in the TAA group and 1.7% (n = 3) in the TBAD group. The overall incidence of postoperative stroke was 0.9% (n = 4), with 1.2% (n = 3) and 0.6% (n = 1) in the TAA and TBAD groups, respectively (p = 0.90). Paraplegia developed in 1.7% (n = 7) of patients, with 2.4% (n = 6) in the TAA group and 0.6% (n = 1) in the TBAD group. Freedom from aortic-related death was not significantly different between the two etiologies; however, thoracic reintervention was more common in the TBAD group (p = 0.003), with endoleak being the most common indication for reintervention. Additionally, retrograde type A aortic dissection occurred in four TBAD cases, while migration occurred in three TAA cases. The perioperative results of TEVAR for TAA and TBAD were satisfactory. The long-term results were unfavorable owing to the occurrence of etiology-specific and common complications. In terms of the high frequency of reintervention, the long-term complications associated with TEVAR are etiology specific.

Mid- and long-term results of open repair for chronic type B aortic dissection in endovascular era.

Medical management is the standard treatment of chronic type B aortic dissection (CTBAD). However, the roles of open surgical repair (OSR) and thoracic endovascular repair (TEVAR) in patients with CTBAD remain controversial. Thus, this study aimed to assess and compare the mid- and long-term clinical outcomes of OSR via left thoracotomy with that of TEVAR for CTBAD. The data of 85 consecutive patients who underwent surgery for CTBAD from April 2007 to May 2021 were retrospectively reviewed. The patients were divided into two groups: Group G, which included patients who underwent OSR, and Group E, which included patients who underwent TEVAR. Groups G and E comprised 33 and 52 patients, respectively. Preoperative and postoperative computed tomography (CT) studies were retrospectively analyzed for the maximum diameter. The mean duration of the follow-up period was 5.8 years. Operative mortality did not occur. There was no difference in complications, such as stroke (G: 2 vs. E: 0, p = 0.30), paraplegia (G: 1 vs. E: 1, p = 0.66), and respiratory failure (G: 2, vs. E: 0, p = 0.30). The difference in preoperative factors was observed, including the intervals between onset and operation (G; 4.9 years vs. E; 1.9 years, p < 0.01), maximum diameter in preoperative CT (G; 59.0 mm vs. E; 50.5 mm, p < 0.001), and maximum false lumen diameter (G; 35.5 mm vs. E; 29.0 mm, p < 0.01). There was no significant difference in the mid- and long-term survival rates (p = 0.49), aorta-related deaths (p = 0.33), and thoracic re-intervention rates (p = 0.34). Postoperative adverse events occurred in Group E: four cases of retrospective type A aortic dissection, two cases of aorto-bronchial fistula, and one case of aorto-esophagus fistula. Aorta-related death and re-intervention rates crossed over in both groups after seven years postoperatively. Although endovascular repair of CTBAD is less invasive, the rate of freedom from re-intervention was unsatisfactory. Some fatal complications were observed in the endovascular group, and the mid- and long-term outcomes were reversed compared with those in the OSR group. Although OSR is an invasive procedure, it could be performed safely without perioperative complications. OSR has more feasible mid- and long-term outcomes.

Comparison of the novel Ankura Plus stent and Castor stent for the treatment of Stanford type B aortic dissection with an insufficient proximal anchoring area.

OBJECTIVE: To compare the efficacy and safety of the Ankura Plus and Castor stents in Stanford type B aortic dissection (TBAD) with an insufficient proximal anchoring area. METHODS: Between January 2020 and October 2022, 54 patients with TBAD were enrolled, including 16 patients with Ankura Plus stents and 38 patients with Castor stents. Data from the two stents were retrospectively analyzed. RESULTS: The surgical success rate for both stents was 100%, and no endoleaks or deaths occurred during hospitalization. The Ankura Plus stent group had a longer surgery time than the Castor stent group (122.6±5.1 vs. 103.7±10.0, P ＜0.001). After an average follow-up of 12 months, the patency rates of the main and branch stents were 100% in both groups. The diameter of the true lumen (TL) was significantly increased, the diameter of the false lumen (FL) was reduced, and there was no statistically significant difference in the probability of complete thrombosis of the FL (68.8% vs. 67.6%, P=0.993). There were no significant differences in the incidences of renal failure (6.3% vs. 8.1%, P = 0.814), stroke (6.3% vs. 2.7%, P = 0.520), or endoleaks (6.3% vs. 10.5%, P = 0.621) between the Ankura Plus and Castor stent groups. One patient in the Castor stent group underwent reintervention because of a type I endoleak three months after surgery. One patient in the Ankura Plus stent group had an additional covered stent placed after one month due to distal TL stenosis of the main stent. One patient in the Castor stent group died of renal failure four months after surgery. CONCLUSION: Both the Ankura Plus and Castor stents are feasible, safe, and effective in the treatment of TBAD with an insufficient proximal anchoring area. Additional long-term studies are required to evaluate the robustness and applicability of Ankura Plus stents.

Physician-modified funnel-shaped covered stent for selective false lumen exclusion in chronic type B aortic dissection.

PURPOSE: To describe the technique of off-centering a balloon-expandable covered stent for selective occlusion of a distal entry tear (ET) in a patient, conservatively treated for chronic type B aortic dissection (cTBAD), presenting FL expansion. TECHNIQUE: A 63-year-old male, with conservatively managed cTBAD, presented at follow-up with FL partial thrombosis and expansion (thoracic aorta FL from 21 mm to 27 mm and abdominal aorta FL from 11 mm to 15 mm in 6 months). No proximal ET was identifiable. Distal FL perfusion was caused by an ET in the abdominal aorta feeding a 2 mm accessory renal artery (ARA). As the aortic diameter was below the threshold for endovascular repair, a selective occlusion of the distal ET and ARA was planned. A balloon-expandable covered stent was modified by off-centering the covered stent proximally and resulting in a funnel-shape occluder after deployment across the ET into the ARA. To prevent type Ic endoleak due to possible FL expansion caused by an intra-operatively detected phrenic artery (PA), coils were deployed into the lumen of the modified stent and the ARA. The pre-discharge computed tomography angiography showed exclusion of both the ARA and ET and a type 2 endoleak from the PA. CONCLUSION: A balloon-expandable covered stent can be modified by off-centering the covered stent resulting in a funnel shape to adapt to different diameter requirements.