Endovascular Treatment of Aortoiliac Aneurysms With the Bell-Bottom Technique: A Systematic Review and Meta-Analysis.

OBJECTIVE: Aneurysmal degeneration of the common iliac artery (CIA) can pose a challenge to achieve distal landing zone sealing at the time of endovascular abdominal aortic aneurysm repair (EVAR). The aim of this study was to summarize the current literature regarding the bell-bottom technique (BBT) for ectatic CIAs during EVAR. METHODS: This study was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Eligible articles were identified through a comprehensive search of PubMed, Scopus, and Cochrane Central published until April 2023. A meta-analysis was conducted using the random effects model and the I2 statistic was used to assess for heterogeneity. The primary endpoints were type Ib/III endoleak, graft occlusion/limb embolization, and reintervention rate. Secondary endpoints included perioperative adverse events and mortality. RESULTS: Overall, twenty-six studies and 4332 patients with flared limbs were included. The pooled estimate for type Ib/III endoleak was 4% (95% CI: 2-6, I2 = 85.6%), for reintervention rate was 9% (95% CI: 6-12, I2 = 90.4%), and for overall mortality was 10% (95% CI: 4-19, I2 = 97.3%). No aneurysm related deaths were recorded. Comparative analysis showed similar type Ib/III endoleak, graft occlusion, and reintervention rates between the EVAR BBT, iliac branch endoprosthesis (IBE), and embolization of the internal iliac artery followed by extension of the iliac limb to the external iliac artery (EIE) groups. CONCLUSIONS: The use of flared limbs could be considered a reasonable first line choice for EVAR cases with CIA ectasia as it is simpler, allows for future IBE or EIE and does not increase the risk for type Ib/III endoleak or graft occlusion. Further comparative studies with longer follow-up are needed.

iCover as Bridging Stent Graft in Fenestrated Endovascular Aortic Aneurysm Repair.

BACKGROUND: Complex endovascular repair with fenestrated or branched stent grafts is a common approach for treating various types of aortic aneurysms. Bridging stent grafts (BSs) are crucial in connecting aortic endoprosthesis to target vessels, yet current options have demonstrated significant complications. OBJECTIVE: This retrospective single-center study evaluates the initial outcomes and durability of the iCover stent graft (iCover-SG) when used as a BS in fenestrated endovascular aneurysm repair (FEVAR). METHODS: Retrospective analysis screened procedures for complex aortic aneurysms between August 2021 and January 2024. Patients who underwent FEVAR with iCover-SG as BS were included. Primary and secondary endpoints focused on freedom from iCover-SG-related target vessel instability, technical success, and postoperative outcomes. RESULTS: Within the cohort of 28 patients, 94 iCover-SGs were used as BS, supplying 87 target vessels. The freedom from iCover-SG-related target vessel instability throughout the study reached 94% (82/87). Technical success rates were notably high, with primary success achieved in 94% of cases and secondary success in 99%. Over the follow-up duration, there were instances necessitating reintervention related to iCover-SG, including 4 cases of endoleak, 2 cases of T1cEL, and 2 cases of T3cEL. In-hospital mortality was 7% (n=4), with 2 cases attributed to intraoperative complications. Importantly, no deaths were directly attributed to iCover-SG-related issues. CONCLUSION: The iCover-SG demonstrates promising initial outcomes as a BS in FEVAR, with high technical success rates and satisfactory rates of target vessel instability. Continued monitoring and further studies are warranted to assess long-term durability and outcomes. CLINICAL IMPACT: This study shows that the iCover stent graft achieves satisfactory technical success and target vessel stability in the short- and mid-term when used as a bridging stent graft in FEVAR procedures. Its successful integration into clinical practice broadens the range of available options, providing clinicians with more versatile tools for managing complex endovascular aortic aneurysms. This expanded selection of bridging stent grafts allows for more personalised treatment strategies, improving procedural precision and patient outcomes. The iCover stent graft's reliable performance highlights its potential as a valuable addition to current endovascular techniques, ultimately enhancing patient care in challenging cases.

Assessing the diagnostic accuracy of artificial intelligence in post-endovascular aneurysm repair endoleak detection using dual-energy computed tomography angiography.

Purpose: The aim of this study was to evaluate the diagnostic accuracy of an artificial intelligence (AI) tool in detecting endoleaks in patients undergoing endovascular aneurysm repair (EVAR) using dual-energy computed tomography angiography (CTA). Material and methods: The study involved 95 patients who underwent EVAR and subsequent CTA follow-up. Dualenergy scans were performed, and images were reconstructed as linearly blended (LB) and 40 keV virtual monoenergetic (VMI) images. The AI tool PRAEVAorta®2 was used to assess arterial phase images for endoleaks. Two experienced readers independently evaluated the same images, and their consensus served as the reference standard. Key metrics, including accuracy, precision, recall, F1 score, and area under the receiver operating characteristic (ROC) curve (AUC), were calculated. Results: The final analysis included 94 patients. The AI tool demonstrated an accuracy of 78.7%, precision of 67.6%, recall of 10 71.9%, F1 score of 69.7%, and an AUC of 0.77 using LB images. However, the tool failed to process 40 keV VMI images correctly, limiting further analysis of these datasets. Conclusions: The AI tool showed moderate diagnostic accuracy in detecting endoleaks using LB images but failed to achieve the reliability needed for clinical use due to the significant number of misdiagnoses.

Optimal size of Frozenix for true thoracic aneurysms: is downsizing an option?

OBJECTIVE: During total arch replacement (TAR) using frozen elephant trunk (FET) technique with Frozenix for true thoracic aortic aneurysm (tTAA), oversized FET tends to be chosen similar to the endovascular devise selection. However, the oversized FET is considered a risk factor for intimal injury. The appropriate size selection of FET remains insufficiently understood. METHODS: Between October 2014 and March 2022, a total of 49 patients underwent TAR using Frozenix for tTAA. Out of 49 patients, four patients planned to staged surgery were excluded, 19 patients were operated on with an undersized Frozenix compared with the descending aorta (undersized FET group) and in 26 patients an equal or oversized Frozenix was used (oversized FET group). Clinical outcomes and postoperative diameter changes were investigated. RESULTS: In-hospital mortality was 0%. The mean diameter of Frozenix and the descending aorta was 30.7 mm and 28.8 mm, respectively, in the oversized FET group, and 26.7 mm and 30.1 mm in the undersized FET group. Postoperative computed tomography (CT) demonstrated no endoleaks not only in the oversized FET group but also in the undersized FET group. CT also revealed that undersized FET had expanded more than the original diameter in all cases except for two, with an average of 2.47 ± 1.53 mm. Additionally, the descending aorta covered with Frozenix shrank in 10 patients (53%). Postoperative adverse aortic events were not observed. CONCLUSIONS: Undersized Frozenix tightly fit the descending aorta and resulted in complete sealing without endoleaks. Oversized FET is not strictly necessary considering the size-related adverse complications.

Next-Generation Frozen Elephant Trunk Technique in the Era of Precision Medicine.

The frozen elephant trunk (FET) technique can be applied to extensive aortic pathology, including lesions in the aortic arch and proximal descending thoracic aorta. FET is useful for tear-oriented surgery in dissections, managing malperfusion syndrome, and promoting positive aortic remodeling. Despite these benefits, complications such as distal stent-induced new entry and spinal cord ischemia can pose serious problems with the FET technique. To prevent these complications, careful sizing and planning of the FET are crucial. Additionally, since the FET technique involves total arch replacement, meticulous surgical skills are essential, particularly for young surgeons. In this article, we propose several techniques to simplify surgical procedures, which may lead to better outcomes for patients with extensive aortic pathology. In the era of precision medicine, the next-generation FET device could facilitate the treatment of complex aortic diseases through a patient-tailored approach.

The usefulness of contrast-enhanced subtraction magnetic resonance imaging for detecting endoleaks after endovascular aortic repair with prophylactic intraoperative sac embolization.

BACKGROUND: Metallic and hyperdense artifacts and T1-shortening substances in the abdominal aortic aneurysm (AAA) sac generated by embolic materials and lipiodol pose challenges in the identification of endoleaks on follow-up computed tomography (CT) or magnetic resonance imaging (MRI). PURPOSE: To evaluate the usefulness of contrast-enhanced subtraction MRI (CES-MRI) for detecting endoleaks after endovascular abdominal aortic aneurysm repair (EVAR) with intraoperative AAA sac embolization compared with CE-CT, this study was conducted. MATERIAL AND METHODS: In this study, 28 consecutive patients who underwent EVAR with prophylactic AAA sac embolization were included. All patients underwent CES-MRI and CE-CT to detect endoleaks. The definitive diagnosis of endoleaks was a consensus reading of CE-CT and CES-MRI by two certified radiologists, in addition to angiography or reproducible radiological findings in the observational examination. Analysis was performed to evaluate which examination was better for detecting endoleaks. RESULTS: The sensitivity, specificity, and area under the curve of CE-CT and CES-MRI according to observer 1 were 50%, 100%, and 0.813 (95% confidence interval [CI] = 0.625-1.00) and 100%, 95%, and 0.997 (95% CI = 0.984-1.00), respectively, and those according to observer 2 were 50%, 100%, and 0.750 (95% CI = 0.514-0.986) and 100%, 95%, and 0.969 (95% CI = 0.903-1.00), respectively. Intolerable artifacts were significantly observed on CE-CT. The severity of the artifacts did not depend on the stent graft on CT and MRI. CONCLUSION: Although no significant difference was observed, CES-MRI tended to have better accuracy for endoleak detection in EVAR with intraoperative AAA sac embolization than CE-CT.

Preemptive treatment of type II endoleak for abdominal aortic aneurysm with renal fusion (horseshoe kidney).

OBJECTIVE: To assess viability and safety of preemptive treatment of type II endoleak for abdominal aortic aneurysm (AAA) repairs. METHODS: A 69-year-old man with renal fusion (horseshoe kidney) was referred for treatment of a 5.5 cm AAA. His anatomy was suitable for endovascular repair. The risk for type II endoleak was increased because of multiple infrarenal arterial orifices originating within the aneurysm sac. These included an accessory renal artery that supplied the renal isthmus, a patent inferior mesenteric artery, and a pair of large lumbar arteries originating from a single orifice (8 mm) at L3 spinal level. The lumbar orifice was selectively cannulated and occluded with thrombogenic coils 1 week prior to his endovascular aneurysm repair. RESULTS: Aneurysm repair was uneventful with no signs of early or delayed endoleak and long-term follow-up of 5 years. CONCLUSIONS: Preemptive coil embolization of perianeurysmal arteries may be considered as a safe and effective strategy for management of potential type II endoleak.

Fate assessment of the ectatic common iliac artery using flared limb during endovascular aneurysm repair.

OBJECTIVES: This study aimed to evaluate the outcomes and anatomical predictors of the complications of flared limb (FL) use for ectatic common iliac arteries accompanied by abdominal aortic aneurysm treated with endovascular aneurysm repair (EVAR). METHODS: In this single-center retrospective study, we reviewed data from 391 patients (638 limbs) treated between 2005 and 2020. The cohort was divided into two groups. The standard limbs (SLs, n = 403) included stent graft (SG) of <20 mm in diameter and the FLs (n = 235) included stent graft of ≥20 mm in diameter. Complications within 30 days were investigated as the short-term outcome. Limb events during follow-up including type Ib endoleak (EL), type IIIa EL, and limb occlusion were compared between SLs and FLs using log-rank test. RESULTS: Early results indicated that the FL group had a significantly higher incidence of intraoperative type Ib EL at 5.1% (12), than 1.7% (7) in the SLs (p = .016). For 19 patients in whom intraoperative type Ib EL was discovered, SG extension alone or internal iliac artery embolization was all performed before completing the procedure. Overall, we noted one case of type Ib EL and two cases of limb events in each group at 30 days. Over a median follow-up of 39 months, 31 (4.9%) events (17 type Ib EL, 2 type IIIa EL, and 12 limb events), 13 (5.5%) in FLs and 18 (4.5%) in SLs (p = .984), were observed. The FLs had significantly higher rates of aortic sac enlargement, with 46 (19.6%) cases for FLs and 36 (8.9%) for SLs (p < .001). The Kaplan-Meier analysis revealed significant differences at 5 years in SLs versus FLs for freedom from type Ib EL (96.6% vs 82.4%, respectively; p < .001) and no difference in freedom from limb events (94.7% vs 84.5%, respectively; p = .519). Furthermore, no difference was observed for overall survival and aneurysm-related mortality. CONCLUSIONS: Although an FL for EVAR is used to treat dilated iliac arteries, there is an increased risk of intraoperative and late type Ib EL and aortic sac enlargement. Long-term close follow-up is mandatory, especially in the patients who undergo EVAR using FLs.

Abdominal aneurysm sac thrombus CT density and volume after EVAR: which association with underlying endoleak?

BACKGROUND: Our aim was to analyse abdominal aneurysm sac thrombus density and volume on computed tomography (CT) after endovascular aneurysm repair (EVAR). METHODS: Patients who underwent EVAR between January 2005 and December 2010 and had at least four follow-up CT exams available over the first five years of follow-up were included in this retrospective single-centre study. Thrombus density and aneurysm sac volume were calculated on unenhanced CT scans. Linear mixed models were used for data analysis. RESULTS: Out of 82 patients, 44 (54%) had an endoleak on post-EVAR contrast-enhanced CT. Thrombus density significantly increased over time in both the endoleak and non-endoleak groups, with a slope of 0.159 UH/month (95% confidence interval [CI] 0.115-0.202), p < 0.0001) and 0.052 UH/month (95% CI 0.002-0.102, p = 0.041). In patients without endoleak, a significant decrease in aneurysm sac volume was identified over time (slope -0.891 cc/month, 95% CI -1.200 to -0.581); p < 0.001) compared to patients with endoleak (slope 0.284 cc/month, 95% CI -0.031 to 0.523, p = 0.082). The association between thrombus density and aneurysm sac volume was positive in the endoleak group (slope 1.543 UH/cc, 95% CI 0.948-2.138, p < 0.001) and negative in the non-endoleak group (slope -1.450 UH/cc, 95% CI -2.326 to -0.574, p = 0.001). CONCLUSION: We observed a progressive increase in thrombus density of the aneurysm sac after EVAR in patients with and without endoleak, more pronounced in patients with endoleak. The association between aneurysm volume and thrombus density was positive in patients with and negative in those without endoleak. RELEVANCE STATEMENT: A progressive increase in thrombus density and volume of abdominal aortic aneurysm sac on unenhanced CT might suggest underlying endoleak lately after EVAR. KEY POINTS: Thrombus density of the aneurysm sac after EVAR increased over time. Progressive increase in thrombus density was significantly associated to the underlying endoleak. The association between aneurysm volume and thrombus density was positive in patients with and negative in those without endoleak.

Exploring Type IIIb Endoleaks: A Literature Review to Identify Possible Physical Mechanisms and Implications.

Endoleaks are common complications following endovascular aneurysm repair (EVAR). They can be classified into low-pressure and high-pressure endoleaks. High-pressure endoleaks, which include Type I and Type III endoleaks, pose a significant risk of rupture and require urgent treatment. The aim of our study is to review published case reports and case series to assess the impact of Type IIIb endoleaks in EVAR and to identify possible mechanisms contributing to these endoleaks. This review targeted case reports and case series published between January 1998 and December 2022. A total of 62 case reports and case series were identified, encompassing 156 patients with Type IIIb endoleaks. Data collection was performed by three consultants who thoroughly discussed each report before registering it into an analyzable data set. Our analysis revealed that, beyond material imperfections, certain endograft configurations or conformations, endograft redundancy, and the physical forces acting on the grafts may lead to increased stress on specific parts of the endografts, potentially exceeding their design limits. Factors contributing to redundancy and unfavorable conformation of the endograft include secondary interventions for any cause (such as other types of endoleaks), EVAR performed outside the instructions for use (IFUs), endograft migrations, or larger initial aneurysm diameter.

An Expert-Based Review on the Relevance and Management of Type 2 Endoleaks Following Endovascular Repair of Ruptured Abdominal Aortic Aneurysms.

Ruptured abdominal aortic aneurysms (rAAAs) are life-threatening and require emergent surgical therapy. Endovascular aortic repair for rupture (rEVAR) has become the leading strategy due to its minimal invasive approach with expected lower morbidity and mortality, especially in patients presenting with hemodynamic instability and relevant comorbidities. Following rEVAR, intraoperative angiography or early postinterventional computed tomography angiography have to exclude early type 1 or 3 endoleaks requiring immediate reintervention. Persistent type 2 endoleaks (T2ELs) after rEVAR, in contrast to elective cases, can cause possibly lethal situations due to continuing extravascular blood loss through the remaining aortic aneurysm rupture site. Therefore, early identification of relevant persistent T2ELs associated with continuous bleeding and hemodynamic instability and immediate management is mandatory in the acute postoperative setting following rEVAR. Different techniques and concepts for the occlusion of T2ELs after rEVAR are available, and most of them are also used for relevant T2ELs after elective EVAR. In addition to various interventional embolization procedures for persistent T2ELs, some patients require open surgical occlusion of T2EL-feeding arteries, abdominal compartment decompression or direct surgical patch occlusion of the aneurysm rupture site after rEVAR. So far, in the acute situation of rAAAs, indications for preemptive or intraoperative T2EL embolization during rEVAR have not been established. In the long term, persistent T2ELs after rEVAR can lead to continuous aneurysm expansion with the possible development of secondary proximal type I endoleaks and an increased risk of re-rupture requiring regular follow-up and early consideration for reintervention. To date, only very few studies have investigated T2ELs after rEVAR or compared outcomes with those from elective EVAR regarding the special aspects of persisting T2ELs. This narrative review is intended to present the current knowledge on the incidence, natural history, relevance and strategies for T2EL management after rEVAR.

Comparative Efficacy and Safety of Self-Expandable vs. Balloon-Expandable Stent Grafts in Visceral Artery Aneurysm Management.

PURPOSE: This study assesses the efficacy and safety of self-expandable (SE) versus balloon-expandable (BE) stent grafts for managing visceral artery aneurysms (VAAs), focusing on procedural success and complication rates. MATERIALS AND METHODS: We conducted a retrospective analysis of VAA patients treated at our institution from April 2006 to September 2021. The study reviewed patient demographics, aneurysm characteristics, treatment details, and outcomes, including endoleaks. RESULTS: Among the 23 patients analyzed, splenic artery aneurysms represented 44% of cases. Fifteen patients were treated with balloon-expandable stent grafts (BE SGs), and eight patients were treated with self-expandable stent grafts (SE SGs). For saccular aneurysms, the average neck size was 10.10 ± 8.70 mm in the BE group versus 18.50 ± 3.40 mm in the SE group (p = 0.23), with an average sac size of 20.10 ± 18.9 mm in the BE group versus 15.60 ± 12.7 mm in the SE group (p = 0.16). The average sac-to-neck ratio was 1.69 ± 2.23 in the BE group versus 1.38 ± 0.33 in the SE group (p = 0.63). The BE group exhibited a significantly higher endoleak rate (60%) compared to the SE group (12.5%; p = 0.03). CONCLUSIONS: While further investigation is needed to fully assess the outcomes of stent graft treatment for VAAs, initial data show a significantly higher endoleak rate with BE SGs compared to SE SGs. The SE SGs may offer better outcomes due to their superior ability to conform to tortuous and mobile visceral arteries.

Endovascular Conversion of a Failed Nellix AAA-Repair by a Custom-Made Branched Device.

PURPOSE: This technical note presents a case of a patient with a failed Nellix device (Endologix, Irvine, Calif) who was not deemed fit for open conversion. Our planned approach for repair involved an endovascular procedure utilizing a custom-made branched device. TECHNIQUE: An endovascular repair was performed via a custom-made four outer branched device in conjunction with a custom-made bifurcated graft featuring inverted limbs (Cook Inc., Bloomington, Ind). All branches were connected to the target vessel with Gore Viabahn VBX balloon-expandable covered stents (Gore & Associates Inc.). CONCLUSION: Endovascular conversion with branched endovascular repair in a patient not deemed fit for open surgery was successfully performed, thereby reducing the risk of a high morbid and mortal procedure. CLINICAL IMPACT: Novel useful treatment solution of failed EVAR with Nellix device.

Imaging in Interventional Radiology: Applications of Contrast-Enhanced Ultrasound.

This review explores the applications of contrast-enhanced ultrasound (CEUS) in interventional radiology, focusing on its role in endoleak detection after endovascular abdominal aortic aneurysm repair (EVAR), periprocedural thermal ablation guidance, and transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC). CEUS offers a dynamic assessment for the detection of endoleak following EVAR, facilitating accurate diagnosis and classification. In periprocedural thermal ablation, CEUS enhances target lesion delineation with the visualization of real-time perfusion changes, optimizing treatment strategies and reducing residual tumor rates. Finally, CEUS has demonstrated efficacy in intraprocedural evaluation and postprocedural follow-up in TACE for HCC, offering early detection of residual tumor enhancement and providing an alternative for patients with contraindications to contrast-enhanced computed tomography or magnetic resonance imaging. Overall, CEUS is a versatile and valuable tool with many applications to offer interventional radiologists enhanced diagnostic capabilities and improved patient management.

Evaluating the feasibility of contrast-enhanced ultrasound for detecting after preemptive coiling endoleaks in endovascular aortic aneurysm repair: A pilot study.

Endovascular aortic aneurysm repair is widely used for the treatment of abdominal aortic aneurysm (AAA), but has a 10% to 40% incidence of type II endoleak during follow-up. There are various techniques to treat these endoleaks in the case of enlarging of the AAA, but the clinical effectiveness is low. In recent years, preemptive AAA sac embolization has shown some encouraging results with significant AAA shrinkage. However, the presence of embolic material can complicate continued endoleak detection making assessment of treatment outcome difficult. We investigate the ability of contrast-enhanced-ultrasound examination to detect endoleaks in patients undergoing preemptive coil embolization of the AAA sac.

Understanding Type II Endoleak: A Harmless Imaging Finding or a Silent Threat?

Type II endoleak (T2EL) represents a challenging clinical entity following endovascular abdominal aortic aneurysm repair (EVAR). Although several studies have suggested that T2ELs are related to an increased risk of aneurysm sac growth and subsequent rupture, the exact role that T2ELs play in long-term outcomes remains debatable. Understanding the pathophysiology, diagnostic modalities, and management options of T2ELs is important for patients' safety and proper resource utilization. While conservative management may be suitable for asymptomatic patients with a stable aneurysm size, interventional approaches, including transarterial embolization, direct sac puncture embolization and open conversion have been described for patients with persistent T2EL associated with sac expansion. However, more research is needed to better determine the clinical benefit of such interventions. A thorough evaluation of all endoleak types before T2EL treatment would be reasonable for patients with T2ELs associated with sac expansion. Further studies are needed to refine treatment strategies aimed at minimizing T2EL-related complications. Collaborative efforts among vascular specialists, radiologists, and researchers are of paramount importance to address this ongoing clinical challenge.

In vitro quantification of stent-graft behaviour during chimney thoracic endovascular aortic repair.

OBJECTIVE: To quantify dynamic gutter phenomena and endograft deformations during double chimney thoracic endovascular aortic repair (ch-TEVAR) in a physiological model of the thoracic aorta subjected to pulsatile haemodynamic conditions. METHODS: Two in vitro procedures revascularizing the brachiocephalic trunk and left common carotid artery were performed representing both balloon-expandable (BE, Ankura-BeGraft) and self-expandable (SE, Ankura-Viabahn) double ch-TEVAR configurations. Retrospectively gated computed tomography (CT) was used to evaluate endograft behaviour. Device interactions were characterised according to gutter volume, gutter surface deviation, and endograft deformation (D-ratio) at end-diastolic and peak-systolic aortic pressure. RESULTS: Use of BE chimney grafts resulted in three times total gutter volume compared to SE chimney grafts. Gutter volumes were observed to vary dynamically between the end-diastolic and peak-systolic phases of the cardiac cycle, with the most substantial change associated with the BE configuration. Chimney graft deformations were dependent on device type, with SE devices exhibiting up to twice the deformation as BE devices. When adjacent, SE chimney grafts were observed to support each other, and thus tended towards a more consistently circular shape. CONCLUSION: Gutter and chimney graft behaviour were dependent on device type, and exhibited both spatial and temporal variability. This study emphasises notable differences between BE and SE double ch-TEVAR configurations which should be considered when evaluating risk of endoleak. The findings reported here also support the use of gated CT to better identify device-related complications with ch-TEVAR, and can be used in the design of next generation devices.

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.

Late Open Abdominal Aneurysm Reconstruction and Graft Salvage in a Patient With Persistent Endoleak Type II Following Endovascular Aneurysm Repair.

This study highlights a case of late open conversion repair (OCR) for persistent Type II endoleak after endovascular aneurysm repair (EVAR), presenting a 78-year-old male with a history of EVAR for an infrarenal abdominal aortic aneurysm. Despite conservative management of the initial endoleak, the aneurysm sac's progressive growth necessitated open reconstruction to salvage the graft. Successful postoperative outcomes emphasize the critical need for meticulous intervention strategies and surveillance in managing persistent Type II endoleaks. This case underlines the importance of a tailored approach, leveraging both endovascular and open surgical techniques, to optimize long-term outcomes and prevent aneurysm rupture in complex cases.