A Predictive Model for Prolonged Mechanical Ventilation After Triple-Branched Stent Graft for Acute Type A Aortic Dissection.

INTRODUCTION: The aim of this study is to develop a model for predicting the risk of prolonged mechanical ventilation (PMV) following surgical repair of acute type A aortic dissection (AAAD). METHODS: We retrospectively collected clinical data from 381 patients with AAAD who underwent emergency surgery. Clinical features variables for predicting postoperative PMV were selected through univariate analysis, least absolute shrinkage and selection operator regression analysis, and multivariate logistic regression analysis. A risk prediction model was established using a nomogram. The model's accuracy and reliability were evaluated using the area under the curve of the receiver operating characteristic curve and the calibration curve. Internal validation of the model was performed using bootstrap resampling. The clinical applicability of the model was assessed using decision curve analysis and clinical impact curve. RESULTS: Among the 381 patients, 199 patients (52.2%) experienced postoperative PMV. The predictive model exhibited good discriminative ability (area under the curve = 0.827, 95% confidence interval: 0.786-0.868, P < 0.05). The calibration curve confirmed that the predicted outcomes of the model closely approximated the ideal curve, indicating agreement between the predicted and actual results (with an average absolute error of 0.01 based on 1000 bootstrap resampling). The decision curve analysis curve demonstrated that the model has significant clinical value. CONCLUSIONS: The nomogram model established in this study can be used to predict the risk of postoperative PMV in patients with AAAD. It serves as a practical tool to assist clinicians in adjusting treatment strategies promptly and implementing targeted therapeutic measures.

Utilizing Single-Branched Stent in Combination With Fenestration or Chimney for Endovascular Repair of Aortic Arch Lesions With Aberrant Subclavian Artery.

OBJECTIVE: The study was to figure out the feasibility, efficacy, and safety of a single-branched stent graft, namely Castor, in combination with fenestration or chimney in the context of aortic arch lesions presenting with aberrant subclavian artery (ASA) and/or Kommerell's diverticulum (KD). METHODS: All consecutive patients with aortic arch lesions and ASA and/or KD receiving Castor from June 2018 to June 2023 were investigated. RESULTS: Incorporating 18 patients, the study encompassed 11 cases with KD, 3 cases with dysphagia; 2 cases of right-sided aortic arch with left-sided aberrant left subclavian artery (ALSA), and 16 cases of left-sided aortic arch with right-sided aberrant right subclavian artery (ARSA). The mean operation time was 132±23 minutes. The mean measured proximal aortic diameter was 30.9±1.6 mm, and proximal diameter of Castor stent was 34 (32, 34.5) mm, with oversize of 9.1±1.6%; the mean measured branch diameter was 8.8±0.97 mm, and branch diameter of Castor stent was 10 (8, 10) mm, with oversize of 0.86±0.57 mm. Technical success rate was 100%, and no in-hospital mortality, no stroke, and no endoleak were identified. One (5.6%) case with spinal cord ischemia and one (5.6%) case with poor healing of operative site were identified. During the follow-up period, no aortic-related death or secondary intervention was recorded. The maximal aortic diameter was significantly reduced at the sixth postoperative month (padj=0.031); KD diameter was significantly reduced at the third (padj=0.001) and sixth (padj<0.001) postoperative month. CONCLUSION: Totally endovascular repair of aortic arch lesions with ASA and KD via Castor stent in combination with fenestration or chimney is feasible, effective, and safe, which can achieve an encouraging medium-term outcome and provide excellent remodeling at the lesions. CLINICAL IMPACT: Single branched stent in combination with fenestration or chimney achieved a sufficient proximal landing zone and provided an encouraging medium-term outcome in this retrospective review of 18 patients receiving endovascular treatment of pathological aortic arch with aberrant subclavian artery and/or Kommerell's diverticulum. The authors suggest this time-saving and efficient technique to establish systematic experience for the treatment in this kind of patients.

Endovascular Salvage of Type Ia and Ib Endoleaks Using a Physician-Modified Fenestrated/Branched Endograft and an Iliac Branch Device Via Unilateral Transfemoral Arterial Access.

PURPOSE: This study aims to explore the feasibility and effectiveness of a unilateral transfemoral access endovascular salvage technique for complex abdominal aortic aneurysms with concurrent type Ia and Ib endoleaks following previous endovascular repair. CASE REPORT: A 69-year-old female with multiple comorbidities presented with an extent IV thoracoabdominal aortic aneurysm complicated by type Ia and Ib endoleaks and chronically occluded left iliac endoprosthesis after prior endovascular repair. Given the patient's medical complexities, open explant repair was deemed high risk. The case was successfully managed using a physician-modified fenestrated/branched endograft (PM-F/BEVAR) and an iliac branch device (IBD) deployed through a single percutaneous transfemoral access. CONCLUSION: The presented case demonstrates the safety and efficacy of PM-F/BEVAR with concomitant IBD deployment via unilateral transfemoral access. This innovative approach allows endovascular salvage in cases with restricted iliofemoral access and avoids the complexities associated with upper extremity or aortic arch manipulation. While acknowledging the technical challenges, this technique offers a viable alternative for salvaging failed endovascular repairs, emphasizing the importance of real-time modifications in achieving successful outcomes. Further studies and long-term follow-up are warranted to validate the broader applicability and durability of this approach in the management of complex abdominal aortic aneurysms with multiple endoleaks. CLINICAL IMPACT: Although not the conventional approach, unilateral transfemoral access can be utilized to implant either a physician-modified fenestrated aortic endograft or an iliac branch device. Such an approach avoids complicating issues related to upper extremity access. This innovative technique may be necessary when there is a failed prior EVAR in the setting of significant contralateral iliofemoral occlusive disease. Doing both procedures in the same setting to resolve a type Ia and Ib endoleak is feasible as demonstrated in this case report. Expanding the endovascular armamentarium to address EVAR failure will be increasingly useful in the future, especially given the morbidity profile of EVAR explantation.

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.

Unintended Exchange of Target Vessels for Celiac Trunk and Superior Mesenteric Artery Branches in Complex Endovascular Aortic Repair.

PURPOSE: The treatment of thoracoabdominal aortic aneurysms (TAAAs) using branched endovascular aortic repair (BEVAR) is safe and effective. During deployment, the superior mesenteric artery (SMA) branch can unintentionally open into the celiac trunk (CT) ostium and switched catheterization of the SMA from the CT branch and the CT from the SMA branch can be used as an alternative technique in these cases. This study aimed to investigate the outcome of exchanging the intended target vessels (TVs) for the CT and SMA branches during BEVAR. MATERIALS AND METHODS: A single-center retrospective analysis of patients with TAAAs who underwent BEVAR, using off-the-shelf or custom-made devices (CMDs), with an unintended exchange of TVs for the CT and SMA branches was performed. RESULTS: Between 2014 and 2023, 397 patients were treated with BEVAR for TAAA. Eighteen (4.5%) of those patients were treated with an exchange of TVs for the CT and SMA branches. T-branch was used in 9 cases (50%) and the remaining patients were treated with CMDs. Twelve patients were treated electively, 3 were symptomatic and 3 presented with rupture. Of 36 mesenteric TVs in those 18 patients, 34 (94%) were catheterized successfully, including all 18 SMAs and 16 of the 18 CTs. No branch stenosis or occlusion of the switched mesenteric TVs was detected during follow-up. During 30-day follow-up, 3 patients died and during a median follow-up of 3 (interquartile range [IQR]: 1-15) months 3 more patients died. None of the deaths or the 2 unintended reinterventions was induced by the mesenteric TV exchange. The median hospital stay was 14 (IQR: 9-22) days with a median of 4 (IQR: 2-11) days at the intensive care unit. CONCLUSION: The exchange of the mesenteric TVs for the CT and SMA branches during BEVAR with off-the-shelf and CMD endografts is feasible with good TV patency and freedom from TV-related reinterventions. This alternative technique should be considered in selected cases when direct catheterization via the intended branch is deemed more time-consuming or not feasible. CLINICAL IMPACT: This is the first description of using an exchange of target vessels for the celiac trunk and the superior mesenteric artery branches in patients with thoracoabdominal aortic aneurysms undergoing BEVAR, using off-the-shelf or custom-made devices. The high success rate as well as the good clinical results without any branch stenosis or occlusion during follow-up highlight the feasibility of this alternative technique. It could help in challenging cases when catheterization of the intended target vessels is not possible or too time consuming, resulting in higher success rates of BEVAR and better clinical results.

The Impact of Target Vessel Anatomy and Bridging Stent Geometry on Branched Endovascular Aortic Repair Outcomes.

OBJECTIVE: This study aimed to evaluate the impact of target vessel anatomy and bridging stent geometry on target vessel instability in branched endovascular aortic repair (B-EVAR). METHODS: This retrospective, single centre cohort study included all consecutive B-EVARs performed between September 2018 and December 2022 for thoraco-abdominal aortic aneurysm (TAAA) or complex abdominal aortic aneurysm (CAAA). The primary endpoints were target vessel instability and related re-interventions at 12 months. Secondary endpoints were 30 day results, including target vessel instability and re-interventions. Target vessel instability analysis consisted of assessment of target vessel anatomy, including diameter, aortic trunk to branch angle, and tortuosity. Post-operative parameters included change of clock position/horizontal misalignment, bridging length (gap), sealing length, tortuosity, post-stenting angle, and oversizing ratio. RESULTS: A total of 69 patients (TAAA: n = 56, 81%; CAAA: n = 13, 19%) and 271 (133 visceral and 138 renal) target vessels were included. The cumulative incidence of target vessel instability was 4.8%, 6.4%, and 7.9% at one, two, and three years, respectively. In the renal target vessel group, vessel diameter ≤ 4 mm (hazard ratio [HR] 1.28, 95% confidence interval [CI] 1.116 - 2.54; p = .022) and a bridging length ≥ 25 mm (HR 1.320, 95% CI 1.066 - 1.636; p = .011) were associated with increased target vessel instability. In visceral vessels, a change in clock position/horizontal misalignment ≥ 70 minutes (HR 1.072, 95% CI 1.026 - 1.121; p = .002) showed a significant association with target vessel instability. CONCLUSION: Target vessel diameter, bridging length (gap), and horizontal misalignment seemed to be associated with adverse target vessel outcomes. This may be solved with more customised endograft solutions to reduce the negative impact of the latter parameter.

Impact on early outcome after endovascular repair of type B dissection without proximal landing zone using Castor single-branched stent graft-a retrospective cohort study.

Background: The early safety and efficacy of Castor branch stents have been demonstrated. However, the effect of aortic arch morphology on endovascular therapy remains an unresolved issue. This study aims to assess the impact of aortic arch morphology on the early outcomes of endovascular repair using Castor stent graft in patients who have acute type B aortic dissection involving the left subclavian artery (LSA). Methods: This is a retrospective cohort study. From January 2019 to December 2021, forty-one patients scheduled for thoracic endovascular aortic repair (TEVAR) of TBADs from Beijing Anzhen Hospital were enrolled in this retrospective cohort study and divided into two groups based on the length of the proximal landing zone left common carotid artery-LSA (PLZ LCCA-LSA), specifically the distance between the LCCA and the LSA (group A ≤10 mm and group B >10 mm). The study recorded technical success, mortality and aortic-related post-operative adverse events. Morphological indices were analyzed including the bird-beak configuration. The bird-beak configuration refers to the wedge-shaped gap between the undersurface of the endograft and the lesser curvature of the arch. The relationship between the risk of bird-beak configuration and PLZ was assessed with logistic regression analysis. Meanwhile, the relationship between the risk of aortic-related adverse events and bird-beak configuration was assessed with logistic regression analysis. Follow-up data were analyzed by Kaplan-Meier life table analysis. Results: The study included 41 patients with a mean age of 63.1±9.2 years, of which 80.5% were male. 18 patients from group A and 23 patients from group B were included in the comparative analysis. There were no significant differences in aortic-related adverse events, bird-beak phenomenon and re-intervention between groups A and B in 30-day outcomes. Six-month outcomes: aortic-related adverse events and the bird-beak phenomenon were observed in 11 (26.8%) and 12 (29.3%) patients, respectively. There was a significant difference in the occurrence of aortic-related adverse events (P=0.036) and bird-beak phenomenon (P=0.002) between groups A and B. In comparison to group B, the aortic-related adverse event rate was significantly higher in group A, with event-free rates of 83.3%, 83.3%, and 72.2% at 1, 3, and 6 months, respectively (P=0.020). Multivariable logistic regression analyses revealed that PLZ LCCA-LSA length [odds ratio (OR) 0.79; 95% CI: 0.64 to 0.97; P=0.026] was significantly associated with the occurrence of the bird-beak configuration, and bird-beak (OR 17.19; 95% CI: 2.24 to 131.81; P=0.006) was a significant risk factor for aortic-related adverse events. Conclusions: TEVAR with LSA revascularization has good early outcomes. However, it is more susceptible to aortic adverse events when the PLZ LCCA-LSA is less than 10 mm in length. This should be carefully considered, taking into account the risks and benefits.

Treatment for Stanford type B aortic dissection with insufficient anchoring region using castor integrated branched aortic stent graft.

Background: To investigate the clinical efficacy of Castor integrated branched aortic stent graft for the treatment of Stanford type B aortic dissection with insufficient anchoring area. Methods: Retrospective analysis of clinical data of 26 patients with Stanford type B aortic dissection with insufficient anchoring region (<15 mm) treated by Castor branched aortic stent graft from September 2018 to June 2022 at Ganzhou People's Hospital, including 23 acute cases and 3 chronic cases. Results: Surgical procedures were successfully performed in all 26 patients, and during the perioperative period no complications occurred, such as cerebrovascular accident, stenosis or occlusion of left subclavian artery, progression of reverse avulsion of aortic dissection, and paraplegia. During the operation 2 patients had a small amount of type I endoleak, which disappeared during the postoperative follow-up. The other patients had good postoperative follow-up results. Review of the aortic CTA indicated good stent morphology with patency of the left subclavian artery. Conclusions: The Castor integrated branched aortic stent graft expanded the indications for endoluminal treatment for Stanford type B aortic dissection, which can avoid open surgery and has good clinical outcomes.

Double-branched stent graft and four-stage deployment in total arch repair: safety and feasibility evaluation in porcine models.

OBJECTIVES: The primary objective of this research was to evaluate the safety and feasibility of an innovative double-branched stent graft system employing four-stage deployment technology for aortic arch repair in porcine models. METHODS: The double-branched stent graft system consisted of a proximal polyester artificial blood vessel, the main and double-branched stent grafts and a delivery system. We utilized 12 healthy pigs as experimental animals (6 per group). Postimplantation, samples were collected at 90 and 180 days after the operations. Preoperative and postoperative imaging and intraoperative arterial blood gas analyses were performed. After the pigs were euthanized, the implanted product, surrounding tissue and major organs were collected for pathological analysis. RESULTS: The technical success rate of the stent graft implants was 100% (12/12). All animals survived to the experimental end point. Perioperative assessments showed intact stent grafts, and imaging features at the end of the follow-up period revealed neither endoleak nor device migration. No major adverse cardiovascular events were observed during the postoperative follow-up period. Pathological examinations confirmed the satisfactory biocompatibility of the stent graft. CONCLUSIONS: This innovative double-branched stent graft system with four-stage deployment technology was affirmed as a safe and feasible option for aortic arch repair in accordance with our preclinical evaluation with porcine models.

A predictive model for postoperative adverse outcomes following surgical treatment of acute type A aortic dissection based on machine learning.

Acute type A aortic dissection (AAAD) has a high probability of postoperative adverse outcomes (PAO) after emergency surgery, so exploring the risk factors for PAO during hospitalization is key to reducing postoperative mortality and improving prognosis. An artificial intelligence approach was used to build a predictive model of PAO by clinical data-driven machine learning to predict the incidence of PAO after total arch repair for AAAD. This study included 380 patients with AAAD. The clinical features that are associated with PAO were selected using the LASSO regression analysis. Six different machine learning algorithms were tried for modeling, and the performance of each model was analyzed comprehensively using receiver operating characteristic curves, calibration curve, precision recall curve, and decision analysis curves. Explain the optimal model through Shapley Additive Explanation (SHAP) and perform an individualized risk assessment. After comprehensive analysis, the authors believe that the extreme gradient boosting (XGBoost) model is the optimal model, with better performance than other models. The authors successfully built a prediction model for PAO in AAAD patients based on the XGBoost algorithm and interpreted the model with the SHAP method, which helps to identify high-risk AAAD patients at an early stage and to adjust individual patient-related clinical treatment plans in a timely manner.

Comparison of chimney technique and single-branched stent graft in a cohort of patients with type B aortic dissections: a retrospective cohort study.

Background: Single-branched stent grafts and the chimney technique are widely used in the treatment of type B aortic dissection (TBAD). The main objective of this study was to compare the outcomes of single-branched stent grafts and the chimney technique in the treatment of TBAD. Methods: From January 2019 to December 2021, the retrospective cohort study contained a cohort of 91 patients with TBAD undergoing thoracic endovascular aortic repair (TEVAR) using single-branched stent grafts and the chimney technique. Group A included 55 patients treated with single-branched covered stents, and Group B included 36 patients treated with the chimney technique. We compared the effects of the procedures on peri-/post-operative outcomes between the two groups. The primary endpoint is clinical death, and the secondary endpoints include the patency of branch stents, the incidence of cerebral infarction, false lumen thrombosis, and the proportion of paraplegia. Results: For the baseline data, the two groups of patients show no differences in terms of age, gender, and associated symptoms. All procedures were successfully performed in both groups. The median follow-up period was 17.6 months (range, 10-34 months). During TEVAR, 5 (9.1%) type I endoleaks occurred in group A, and 11 (30.6%) occurred in group B (P<0.05). During follow-up, there were 2 cases (3.6%) of paraplegia and 1 case (1.8%) of cerebral infarction in Group A, while Group B had 1 case (2.8%) of paraplegia. Three patients in group B reported retrograde type A aortic dissection (RTAD), and 1 of them died (2.8%); however, there were no RTAD cases in group A. Complete thrombosis of the false lumen in the thoracic aorta was observed in 45.5% (25/55) of patients in group A and in 41.7% (15/36) in group B (P=0.72). No significant difference in the thrombosis-volume ratio in the whole false lumen was found during follow-up between group A (81.0%±2.9%) and group B (81.8%±2.6%; P=0.23). Conclusions: Branched stent grafts can be used in cases with insufficient proximal landing zones and reduce the occurrence of type 1 endoleak compared to the chimney technique. This may help to prevent RTAD. Further research, including more cases and longer follow-up periods, is needed to substantiate these results.

Clinical outcomes and aortic remodeling after Castor single-branched stent-graft implantation for type B aortic dissections involving left subclavian artery.

Background: The left subclavian artery (LSA) can be intentionally covered by a stent graft to acquire adequate landing zones for a proximal entry tear near the LSA during thoracic endovascular aortic repair (TEVAR). The Castor single-branched stent graft is designed to treat type B aortic dissection (TBAD) to retain the LSA during TEVAR. This study investigates clinical outcomes, aortic remodeling, and abdominal aortic perfusion patterns after TEVAR with the novel Castor device. Methods: From November 2020 to June 2023, 29 patients with TBAD involving the LSA were treated with the Castor single-branched stent graft. In-hospital clinical outcome and aortic computed tomography angiography (CTA) data were analyzed. CTA was performed preoperatively and at follow-up to observe stent morphology; branch patency; endoleak; change in true lumen (TL), false lumen (FL), and transaortic diameters; and abdominal aortic branch perfusion pattern. Results: The technical success rate was 96.6%. One failure was that the branch section did not completely enter the LSA and the main body migrated distally. No in-hospital mortality, paraplegia, or stroke occurred. During follow-up, one type Ib endoleak, four distal new entry tears, and one recurrent type A dissection arose from a new entry tear at the ascending aorta, no stent migration was observed, and the branch patency rate was 100%. At the thoracic aorta, TL diameters significantly increased, FL diameters markedly decreased, and FL was partially or completely thrombosed in most patients at follow-up. At the abdominal aorta, we observed 33.3% of TL growth and 66.7% of TL stabilization or shrinkage. The initial TL ratio at iliac bifurcation negatively predicted abdominal TL growth after TEVAR with a cutoff of 21.0%. Of the 102 abdominal aortic branches, 94.1% of the branches showed no change in perfusion pattern, 3.9% of the branches had an increased TL perfusion, and 2.0% of the branches had an increased FL contribution. Conclusion: The Castor unibody single-branched stent graft offers an efficient endovascular treatment for TBAD involving the LSA. TEVAR with the Castor device effectively induced thoracic FL thrombosis and thoracic TL enlargement and resulted in abdominal TL growth when the initial TL ratio at iliac bifurcation is less than 21.0%. Abdominal aortic branch perfusion patterns remain relatively stable after TEVAR with the Castor stent graft.

Preliminary Outcomes of Zone 2 Thoracic Endovascular Aortic Repair Using Castor Single-Branched Stent Grafts: A Single-Center Experience.

In the context of thoracic endovascular aortic repair (TEVAR), the reconstruction of the left subclavian artery (LSA) has emerged as a crucial component in establishing a sufficient proximal landing zone. However, the technical difficulty of these procedures raises the possibility of endoleaks and neurological consequences. Single-branched stent grafts offer good anchoring and LSA flow for these patients. This study evaluates the feasibility of utilizing novel single-branched stent grafts in the treatment of distal aortic arch disease, identifying good results in the short and medium term. From September 2019 to March 2023, TEVAR and revascularized LSA were performed on ten patients at the Ospedale del Cuore-FTGM in Massa, Italy, using Castor single-branched thoracic aortic stent grafts (Microport Medical, Shanghai, China). The authors' first findings demonstrated that, after an average follow-up of one year, the Castor branching aortic stent graft system was safe and achieving an appropriate proximal landing zone and maintaining sufficient LSA perfusion was possible. With regard to the endovascular treatment of distal aortic arch diseases, this product offers a compelling substitute for surgery. For the purpose of assessing the long-term effectiveness of this approach, the follow-up period should be extended.