Follow-up Computed Tomography Angiography Research Articles

ReMAR: a preoperative CT angiography guided metal artifact reduction framework designed for follow-up CTA of endovascular coiling

Objective. Follow-up computed tomography angiography (CTA) is necessary for ensuring occlusion effect of endovascular coiling. However, the implanted metal coil will introduce artifacts that have a negative spillover into radiologic assessment. Method. A framework named ReMAR is proposed in this paper for metal artifacts reduction (MARs) from follow-up CTA of patients with coiled aneurysms. It employs preoperative CTA to provide the prior knowledge of the aneurysm and the expected position of the coil as a guidance thus balances the metal artifacts removal performance and clinical feasibility. The ReMAR is composed of three modules: segmentation, registration and MAR module. The segmentation and registration modules obtain the metal coil knowledge via implementing aneurysms delineation on preoperative CTA and alignment of follow-up CTA. The MAR module consisting of hybrid convolutional neural network- and transformer- architectures is utilized to restore sinogram and remove the artifact from reconstructed image. Both image quality and vessel rendering effect after metal artifacts removal are assessed in order to responding clinical concerns. Main results. A total of 137 patients undergone endovascular coiling have been enrolled in the study: 13 of them have complete diagnosis/follow-up records for end-to-end validation, while the rest lacked of follow-up records are used for model training. Quantitative metrics show ReMAR significantly reduced the metal-artifact burden in follow-up CTA. Qualitative ranks show ReMAR could preserve the morphology of blood vessels during artifact removal as desired by doctors. Significance. The ReMAR could significantly remove the artifacts caused by implanted metal coil in the follow-up CTA. It can be used to enhance the overall image quality and convince CTA an alternative to invasive follow-up in treated intracranial aneurysm.

Urgent Candy-Plug Technique for Distal False Lumen Occlusion in Chronic Aortic Dissection

IntroductionThis study aimed to assess the impact of urgency on early and midterm outcomes of the Candy-Plug (CP) technique for distal false lumen (FL) occlusion in thoracic endovascular aortic repair (TEVAR) for aortic dissection (AD). MethodsThe CP registry was reviewed, and patients were categorized into elective and urgent/emergent groups for analysis. Endpoints included technical success, clinical success, early (30-day) computed tomography angiography (CTA) findings, early (30-day) mortality, adverse events, aortic remodeling in patients with available CTA follow-up and re-intervention. ResultsA total of 155 patients received a custom-made Candy-Plug with 32 patients (44% males, mean age 61±9 years) were treated urgently vs. 123 patients (63% males, mean age 62±11 years) electively. The primary CP rate was higher in the urgent group; (28/32, (88%) in the urgent group vs. 96/123 (78%) in the elective group, p=051). The mean contrast volume was higher in the urgent group; (157±56ml in the urgent group vs. 130±71ml in the elective group, p=.017). Technical success was achieved in all patients in both groups. Clinical success was achieved in 25/32 (78%) patients in the urgent group vs. 113/123 (92%) in the elective group, p=.159. The early mortality rate was 4/32, (13%) patients in the urgent group vs. 1/123 (1%) in the elective group, p=.120). There was no statistically significant difference regarding the early adverse events between the urgent and elective CP groups. Early aortic-related re-interventions were required in 6/32 (19%) patients in the urgent group vs. 6/123 (5%) in the elective group, p=.094. Thoracic aortic aneurysm sac regression was lower in the urgent group (5/28, (18%) in the urgent group vs. 63/114 (55%) in the elective group, p=001). Stable thoracic aortic aneurysm sac was higher in the urgent group (22/28, (79%) in the urgent group vs. 47/114 (41%) in the elective group, p=000). An increase in thoracic aortic aneurysm sac occurred in 1/28 (4%) patient in the urgent group vs. 4/114 (4%) patients in the elective group, p=.096. ConclusionThe urgent use of the CP technique for distal FL occlusion in AD was feasible and effective. The decrease in aortic FL sac diameter may be affected by the urgent use of CP due to limited sizing availability. However, it achieved high rate of aortic remodeling.

Repeated acute coronary syndrome caused by a mind-bending mural thrombus in ascending aorta: a case report and review of the literature

BackgroundAcute coronary syndrome due to coronary artery embolism in the setting of ascending aortic thrombus is an uncommon condition, even rarer when there is no aortic pathology such as aneurysm, severe atherosclerosis, aortic dissection, or thrombophilia (whether inherited or acquired).Case presentationWe report a case of a 58-year-old male presented with acute chest pain, electrocardiogram showing non-ST-elevation acute coronary syndrome. The computed tomography angiography of coronary artery revealed a mural thrombus in the proximal part of ascending aorta, located above the left coronary artery ostium, without any aortic pathologies. With the exception of hypertension and cigarette smoking, no other risk factors were identified in this patient that may increase the risk of thrombosis. Given the life-threatening risk of interventional therapy and surgery, the patient determinedly opted for anticoagulant and dual antiplatelet therapy. Then he experienced the reoccurrence of chest pain after 6-day treatment, progressed to anterior and inferior ST-segment elevation myocardial infarction. Coronary artery embolism originating from the ascending aortic thrombus was suspected. Considering the hemodynamic instability of the patient, the medical treatment was continued and bridged to warfarin and aspirin after discharge. Follow-up computed tomography angiography at 6 months showed no obstruction in coronary artery and complete resolution of the thrombus. No thromboembolic events occurred henceforward.ConclusionsAcute coronary syndrome could be a manifestation of secondary coronary embolism due to ascending aortic thrombus. Currently, there is no standardized guideline for the treatment of aortic mural thrombus, individualized treatment is recommended. When surgical therapy is not applicable for the patient, anticoagulation and dual antiplatelet treatment are alternative treatments that may successfully lead to the resolution of the aortic thrombus.

Comparative effectiveness of different management strategies for left atrial appendage thrombus in patients on optimal NOAC therapy

Abstract Background Left atrial appendage (LAA) thrombus is the primary cause of stroke and systemic embolism in atrial fibrillation (AF). Novel oral anticoagulants (NOACs) effectively reduce the prevalence of LAA thrombosis and stroke risk. Nonetheless, there is no clear advice for patients with a NOAC-resistant thrombus, necessitating individualized decision-making without strong support of the current guidelines. Aims To analyze patients diagnosed with an LAA thrombus despite adequate NOAC therapy and to compare the efficacy of various therapeutic strategies in achieving thrombus resolution. Methods We retrospectively analyzed patients scheduled for cardioversion or catheter ablation of AF between 2014 and 2023 who were diagnosed with LAA thrombus despite being on optimal NOAC therapy. These patients underwent follow-up transesophageal echocardiography (TEE) or cardiac CT angiography. Changes in treatment modalities were divided into four groups: transition to an alternative NOAC, switch to a vitamin K antagonist (VKA), the addition of an antiplatelet agent, or the deliberate maintenance of the current treatment. Results We analyzed the data of 90 patients comprising 103 cycles of treatment. The patients were either on rivaroxaban (41%), apixaban (32%), dabigatran (15%) or on edoxaban (12%) at the time of the initial TEE. A change to a different NOAC was observed in 37% of cases, transition to a VKA in 22%, supplementation with antiplatelet therapy in 16%, while deliberate absence of treatment modification in 25% of cases. Subsequent follow-up TEE (or CT angiography in a minority of cases) was performed at a median of 68 [43 – 94] days from the baseline evaluation. Successful thrombus resolution was achieved in 72% of cases. Evaluation of therapeutic strategies revealed that any modification of treatment was three times more effective than deliberate no change in treatment; thrombus resolution was observed in 60 (81%) vs. 17 (59%) cases (OR 3.03 [1.18 - 7.75], p = 0.021). Nevertheless, no particular strategy demonstrated superior efficacy over others. Conclusions Resolution of LAA thrombus in patients already on adequate NOAC treatment may require a revision of the prior anticoagulation strategy; however, none of the commonly employed strategies appears to exhibit distinct superiority over the rest.

Use of Artificial Intelligence With Deep Learning Approaches for the Follow-up of Infrarenal Endovascular Aortic Repair.

Endoleaks represent one of the main complications after endovascular aortic repair (EVAR) and can lead to increased re-intervention rates and secondary rupture. Serial lifelong surveillance is required and traditionally involves cross-sectional imaging with manual axial measurements. Artificial intelligence (AI)-based imaging analysis has been developed and may provide a more precise and faster assessment. This study aims to evaluate the ability of an AI-based software to assess post-EVAR morphological changes over time, detect endoleaks, and associate them with EVAR-related adverse events. Patients who underwent EVAR at a tertiary hospital from January 2017 to March 2020 with at least 2 follow-up computed tomography angiography (CTA) were analyzed using PRAEVAorta 2 (Nurea). The software was compared to the ground truth provided by human experts using Sensitivity (Se), Specificity (Sp), Negative Predictive Value (NPV), and Positive Predictive Value (PPV). Endovascular aortic repair-related adverse events were defined as aneurysm-related death, rupture, endoleak, limb occlusion, and EVAR-related re-interventions. Fifty-six patients were included with a median imaging follow-up of 27 months (interquartile range [IQR]: 20-40). There were no significant differences overtime in the evolution of maximum aneurysm diameters (55.62 mm [IQR: 52.33-59.25] vs 54.34 mm [IQR: 46.13-59.47]; p=0.2162) or volumes (130.4 cm3 [IQR: 113.8-171.7] vs 125.4 cm3 [IQR: 96.3-169.1]; p=0.1131) despite a -13.47% decrease in the volume of thrombus (p=0.0216). PRAEVAorta achieved a Se of 89.47% (95% confidence interval [CI]: 80.58 to 94.57), a Sp of 91.25% (95% CI: 83.02 to 95.70), a PPV of 90.67% (95% CI: 81.97 to 95.41), and an NPV of 90.12% (95% CI: 81.70 to 94.91) in detecting endoleaks. Endovascular aortic repair-related adverse events were associated with global volume modifications with an area under the curve (AUC) of 0.7806 vs 0.7277 for maximum diameter. The same trend was observed for endoleaks (AUC of 0.7086 vs 0.6711). The AI-based software PRAEVAorta enabled a detailed anatomic characterization of aortic remodeling post-EVAR and showed its potential interest for automatic detection of endoleaks during follow-up. The association of aortic aneurysmal volume with EVAR-related adverse events and endoleaks was more robust compared with maximum diameter. The integration of PRAEVAorta AI software into clinical practice promises a transformative shift in post-EVAR surveillance. By offering precise and rapid detection of endoleaks and comprehensive anatomic assessments, clinicians can expect enhanced diagnostic accuracy and streamlined patient management. This innovation reduces reliance on manual measurements, potentially reducing interpretation errors and shortening evaluation times. Ultimately, PRAEVAorta's capabilities hold the potential to optimize patient care, leading to more timely interventions and improved outcomes in endovascular aortic repair.

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

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. 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. 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. This study's outcomes demonstrate that it is safe and feasible to deploy a modular single inner-branched stent graft in a porcine model. 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.

Early and midterm outcomes of EVAR with 34 and 36 mm large endograft sizes: A single tertiary center study

Aim: Endovascular aneurysm repair (EVAR) has become a preferred method for accessing anatomically suitable abdominal aortic aneurysms in recent years. Advances in techniques and materials have led to the management of more challenging cases. Anatomical difficulties in the structure of the aneurysm neck can adversely affect the success of the procedure. In this study, we aimed to evaluate early and midterm outcomes in patients with wide-necked infrarenal abdominal aortic aneurysms treated with 34 mm or 36 mm EVAR endografts. Material and Methods: We evaluated infrarenal abdominal aortic aneurysms treated with 34 mm or 36 mm long EVAR allografts between January 2019 and January 2023 at Ankara Bilkent City Hospital Cardiovascular Surgery Clinic. We included and assessed patients with a neck diameter of 28 mm or greater using follow-up computed tomography angiography (CTA). We evaluated early and midterm morbidity and mortality as well as endovascular complications such as endoleak or migration. Results: A total of 58 patients with wide-neck infrarenal abdominal aortic aneurysms underwent 34 mm or 36 mm EVAR endograft deployment. There was no early mortality. The mean follow-up period was 21.7±6.4 months. Eight patients were found to have endoleaks—four had type 2 endoleaks, two had type 1b endoleaks, one had type 3 endoleak and one had type 1a endoleak. Except for type 2 endoleaks, all patients underwent endovascular reintervention. Conclusion: Our study demonstrated the successful application of 34 mm or 36 mm long endografts to patients with abdominal aortic aneurysms with a wide neck diameter. Regarding the midterm outcomes, standard EVAR procedures with large endografts are feasible and have successful outcomes.

Thoracic endovascular repair of descending thoracic aorta aneurysm using thoracic stent graft in a challenging complex patient: An innovative access technique during an emergency using a mini-thoracotomy approach.

Repairing thoracic aortic aneurysms with endovascular aortic repair (TEVAR) is a safe and minimally invasive method with low morbidity and short postoperative recovery. We developed a novel method to treat descending thoracic aortic aneurysms using a mini-thoracotomy approach in complex patients with difficult access. A 56-year-old male patient presented with a 3-day history of chest pain. His past surgical history included infrarenal aortic ligation and right axillobifemoral bypass. Thoracic computed tomography angiography (CTA) revealed a saccular aortic aneurysmal dilatation at zone 2 measuring 4.4 × 4cm. Owing to his surgical history, vascular access through the femoral and iliac arteries or abdominal aorta was impossible. We developed a new technique using a left posterolateral mini-thoracotomy approach to gain vascular access and perform TEVAR, avoiding the need for an open thoracotomy repair. Thoracic CTA performed before discharge revealed complete aneurysmal exclusion and no endoleaks. Postoperative follow-up CTA (6months and annually thereafter) revealed no aneurysm formation or aortic restenosis. The femoral artery, followed by the iliac artery, is the traditional access route for TEVAR. Left posterolateral mini-thoracotomy may be required as an alternative access in complex patients.

A vertebrobasilar junction aneurysm successfully treated with a combination of surgical clipping and flow diverter placement based on the results of computational fluid dynamics analysis: illustrative case.

The treatment of vertebrobasilar junction (VBJ) aneurysms is challenging. Although flow diverters (FDs) are a possible treatment option, geometrical conditions hinder intervention. VBJ aneurysms possess dual inflow vessels from the bilateral vertebral arteries (VAs), one of which is ideally occluded prior to FD treatment. However, it remains unclear which VA should be occluded. A 75-year-old male with a growing VBJ complex aneurysm exhibiting invagination toward the brainstem and causing perifocal edema required intervention. Preoperative computational fluid dynamics (CFD) analysis demonstrated that left VA occlusion would result in more stagnant flow and less impingement of flow than right VA occlusion. According to the simulated strategy, surgical clipping of the left VA just proximal to the aneurysm was performed, followed by FD placement from the basilar artery trunk to the right VA. The patient demonstrated tolerance of the VA occlusion, and follow-up computed tomography angiography at 18 months after FD treatment confirmed the disappearance of the aneurysm. Preoperative flow dynamics simulations using CFD analysis can reveal an optimal treatment strategy involving a hybrid surgery that combines FD placement and direct surgical occlusion for a VBJ complex aneurysm.

Low-profile versus standard-profile stent grafts in the treatment of abdominal aortic aneurysm: a case-matched study.

Endovascular aortic repair (EVAR) is nowadays a widespread method of managing abdominal aortic aneurysm (AAA). Low-profile stent grafts (LPSGs) enable treatment of patients with complex and anatomically challenging aneurysms, and facilitate a percutaneous and thus less invasive procedure. To assess the outcomes of EVAR with low-profile versus standard-profile stent grafts (SPSGs). Thirty-one patients with abdominal aortic aneurysms (AAA) were treated by endovascular aortic repair (EVAR) using LPSGs. The control group of patients treated with SPSGs was matched with MedCalc software. The clinical records and the preoperative and follow-up computed tomography angiography of patients who underwent endovascular treatment of AAA were included in this study. Patients in the LPSG group had significantly more often low access vessel diameter (< 6 mm) compared to the SPSG group (38.7% vs. 6.7%, p = 0.003). In 1-year follow-up, there was no rupture, no infection, no conversion to open repair and no aneurysm-related death. Five secondary interventions were necessary in the SPSG group and only 1 in the LPSG group (p = 0.09). Type of stent graft was not a risk factor of perioperative complications, presence of endoleak or reintervention (p > 0.05). Risk factors for perioperative complications were COPD and conical neck (OR = 6.3, 95% CI: 1.5-25, p = 0.01 and OR = 6.2, 95% CI: 1-39.76, p = 0.04). The risk factor for endoleak was lower maximal aneurysm diameter. The risk factor for reintervention was proximal neck diameter (OR = 0.77, 95% CI: 0.-0.97, p = 0.03). Our study showed that use of LPSGs is a safe and viable method for patients with narrow access vessels who are not eligible for standard-profile systems.

Intraluminal Thrombus of the Extracranial Cerebral Arteries in Acute Ischemic Stroke: Manifestations, Treatment Strategies, and Outcome.

Intraluminal thrombus (ILT) of the cervical arteries is an uncommon finding that can lead to acute or recurrent ischemic stroke. Currently, antithrombotic therapy in the form of antiplatelet and/or anticoagulation is considered the mainstay of treatment, but evidence of which one has a better outcome is lacking. A retrospective cohort study included 28 patients diagnosed with acute stroke or transient ischemic attack with ILT of the extracranial arteries from 2013 to 2022. The primary efficacy outcome was assessed as recurrent stroke, and the primary safety outcome was assessed as hemorrhagic complications. Secondary outcomes were assessed as the resolution of thrombi by CT angiography (CTA) and clinical improvement by the Modified Rankin Scale (mRS) and NIH Stroke Scale (NIHSS). Out of 28 patients, more than half (57.1%; n = 16) were males with a mean age of 57.8 ± 9.5 years and an average BMI of 26.9 ± 4.5 kg/m2. As initial treatment, twenty-four patients received anticoagulation and four received antiplatelet agents. Recurrent strokes were found in four patients (14.29%), and all were initially treated with anticoagulation. One patient in the anticoagulation group had a significant retroperitoneal hemorrhage. None of the patients in the antiplatelets group had a recurrent stroke or bleeding event. Initial treatment with antiplatelet agents significantly improved the NIHSS on day 7 (P = 0.017). A significant improvement in NIHSS on day 90 was observed in the anticoagulant group (P = 0.011). In the follow-up CTA performed on 24 patients, 18 (75%) showed complete resolution (3 out of 3 (100%) in the antiplatelet group and 15 out of 21 (71.43%) in the anticoagulant group). Initial treatment with anticoagulants improves neurologic outcomes in patients with ILT-induced acute ischemic stroke but carries the risk of recurrent stroke and bleeding. However, initial treatment with dual antiplatelet agents appears to have comparable efficacy without sequelae, particularly in atherosclerosis-induced ILT.

Superior cerebellar artery occlusion remaining after thrombectomy for acute basilar artery occlusion

To investigate the incidence and impact of superior cerebellar artery (SCA) occlusion remaining after thrombectomy for acute basilar artery occlusion (BAO). We retrospectively analyzed data from 116 patients who underwent thrombectomy for BAO. The patency of SCA was assessed on final angiograms. Clinical and radiologic data of the patients were retrieved from a prospectively collected database and analyzed. All patients underwent pretreatment and follow-up DWI to detect new infarctions in SCA territory. Ten patients (8.6%) had SCA occlusions on final angiograms. Of these, two patients had bilateral occlusions. A new infarction with a diameter ranged from 4 to 11 mm in corresponding SCA territory occurred in 5 of 10 patients. No patients with SCA occlusions experienced symptomatic cerebellar hemorrhage or malignant cerebellar infarction. Nine of 12 SCA occlusions showed spontaneous recanalization on follow-up CT angiography. Four of 10 patients showed 90-day favorable outcome (mRS 0–3) and 90-day mortality occurred in one patient. SCA occlusions remaining after thrombectomy for acute BAO had a benign clinical course. Most of these lesions recanalized spontaneously. Our study suggests that attempts to recanalize remnant SCA occlusion may be unnecessary after basilar artery thrombectomy.

Safety and learning curve of percutaneous axillary artery access for complex endovascular aortic procedures

BackgroundPercutaneous axillary artery access is increasingly used for large-bore access during interventional vascular and cardiac procedures. The aim of this study was to evaluate the safety and learning curve of percutaneous axillary artery access in patients undergoing complex endovascular aortic repair (fenestrated and branched endovascular aneurysm repair [FBEVAR]) requiring large-bore upper extremity access and to discuss best practices for technique and complication management. MethodsOne-hundred forty-six patients undergoing large-bore percutaneous axillary artery access during FBEVAR in a prospective, nonrandomized, Investigational Device Exemption study between September 2017 and January 2023 were analyzed. Ultrasound guidance and micropuncture were used to access the second portion of the axillary artery and 2 Perclose Proglide or Prostyle devices (Abbott Vascular) were predeployed before the insertion of the large-bore sheath. Completion angiography was performed in all patients to verify hemostatic closure. Axillary artery patency was also assessed on follow-up computed tomography angiography. Patient-related, procedural, and postoperative variables were collected and analyzed. ResultsOne-hundred forty-five patients underwent successful percutaneous axillary artery access; 1 patient failed axillary access and alternative access was established. The left axillary artery was accessed in 115 patients (79%), and the right axillary artery was accessed in 30 patients (21%). The largest profile sheath was 14 F in 4 patients (2.8%), 12F in 133 patients (91.7%), and 8F in 8 patients (5.5%). Ten patients (6.9%) required covered stent placement (Viabahn, W. L. Gore & Associates) for failure to achieve hemostasis; there were no conversions to open surgical repair. Additional adverse events included transient upper extremity weakness in two patients (1.3%) and transient upper extremity paresthesias in two patients (1.3%). Three patients (2%) suffered postoperative strokes, including one unrelated hemorrhagic stroke and two possibly access-related embolic strokes. On follow-up, axillary artery patency was 100%. There was a trend toward decreased closure failure over time, with seven patients (10%) in the early cohort and three (4%) in the late cohort. There was a significant negative correlation between the cumulative complication rate and the cumulative experience. ConclusionsLarge-bore percutaneous axillary artery access provides safe upper extremity large-bore access during FBEVAR, achieving successful closure in >90% of patients with a low incidence of access-related complications. There was a trend toward better closure rates with increasing experience, suggesting a learning curve effect. Application of best practices including ultrasound guidance and angiography may ensure safe application of the technique of percutaneous large-bore axillary artery access.

A single-center experience of type B aortic intramural hematoma

ObjectiveThe outcomes of the best medical treatment (BMT) and intervention treatment (INT) in a single-center experience were reported in type B intramural hematoma (IMH). MethodsFrom February 2015 to February 2021, a total of 195 consecutive patients with type B IMH were enrolled in the study. The primary end point was mortality, and the secondary end points included clinical and imaging outcomes. The clinical outcomes were aortic-related death, retrograde type A aortic dissection, stent graft-induced new entry tear, endoleak, and reintervention. The imaging outcome was evaluated through the latest follow-up computed tomography angiography, which included aortic rupture, aortic dissection, aortic aneurysm, rapid growth of aortic diameter, newly developed or enlarged penetrating aortic ulcer or ulcer-like projection (ULP) and increased aortic wall thickness. Kaplan-Meier curves were used to assess the association between different treatments. ResultsAmong the enrolled patients, 115 received BMT, and 80 received INT. There was no significant difference in early (1.7% vs 2.5%; P = 1.00) and midterm all-cause death (8.3% vs 5.2%; P = .42) between the BMT and INT groups. However, patients who underwent INT were at risk of procedure-related complications such as stent graft-induced new entry tear and endoleaks. The INT group was associated with a profound decrease in the risk of ULP, including newly developed ULP (4.3% vs 26.9%; P < .05), ULP enlargement (6.4% vs 31.3%; P < .05), and a lower proportion of high-risk ULP (10.9% vs 45.6%; P < .05). Although there was no significant difference in the incidence of IMH regression between the two groups, the maximum diameter of the descending aorta in patients receiving INT was larger compared with those treated with BMT. ConclusionsBased on our limited experience, patients with type B IMH treated with BMT or INT shared similar midterm clinical outcome. Patients who underwent INT may have a decreased risk of ULPs, but a higher risk of procedure-related events and patients on BMT should be closely monitored for ULP progression.

Delayed Foreshortening and Prolapse of Silk Vista Baby into Superior Cerebellar Artery Aneurysm

Flow diversion has evolved as a minimally invasive treatment for intracranial aneurysms. The Silk Vista Baby (SVB) can be navigated into small cerebral vessels because it can be deployed through a low-profile microcatheter. We report on treating a patient in his 70s with an unruptured fusiform right superior cerebellar artery aneurysm using an SVB. Significant foreshortening of the device was noted during the initial procedure; however, the position was satisfactory with good apposition and clearance of the aneurysm neck. A stable position of the SVB on 1-day and 2-month postprocedural computed tomography angiography was also demonstrated. Subsequently, a 6-month follow-up computed tomography angiography detected delayed foreshortening and prolapse of the SVB into the aneurysm, for which an additional SVB was placed in a second procedure. There were no complications and the patient remained clinically well. Although the intraoperative foreshortening was not unexpected, the delayed postprocedural behavior of proximal foreshortening and subsequent prolapse of the SVB into the aneurysm have not been previously described. We would like to share this for awareness in this technical note.

Utility of follow-up ultra-high-resolution CT angiography with model-based iterative reconstruction after flow diverter treatment for cerebral aneurysms.

Follow-up examinations after flow diverter (FD) treatment for cerebral aneurysms typically involve magnetic resonance imaging (MRI) or digital subtraction angiography (DSA). However, MRI is prone to vascular defects due to metal artifacts from FD, and DSA carries a risk of ischemic complications. In the context of computed tomography angiography (CTA), this study compares the efficacy of ultra-high-resolution CT (UHRCT) and novel reconstruction techniques, such as model-based iterative reconstruction (MBIR), against conventional methods such as filtered back projection (FBP) and hybrid iterative reconstruction (IR), to determine if they are a viable alternative to DSA in clinical settings. A phantom study was conducted with the full-width half-maximum considered as the FD thickness. This study compared three reconstruction methods: MBIR, FBP, and hybrid IR. A clinical study was also conducted with 21 patients who underwent follow-up CTA after FD treatment. The FD's visibility was assessed using a 4-point scale in FBP, hybrid IR, and MBIR compared to cone-beam CT (CBCT) with angiographic systems. In the phantom study, FBP, hybrid IR, and MBIR visualized thinner FD thicknesses and improved detail rendering in that order. MBIR proved to be significantly superior in both the phantom and clinical study. UHRCT with MBIR is highly effective for follow-up evaluations after FD treatment and may become the first-choice modality in the future.

Long-term outcomes following exclusive use of endovascular aortic repair for ruptured infrarenal abdominal aortic aneurysms.

Long-term outcomes following exclusive use of endovascular aortic repair for ruptured infrarenal abdominal aortic aneurysms.

A pilot study to evaluate a novel localized treatment to stabilize small- to medium-sized infrarenal abdominal aortic aneurysms

ObjectiveThere is no proven therapy to reduce growth rates of small- to medium-sized abdominal aortic aneurysms (AAAs). Ex vivo and animal studies have demonstrated that a novel stabilizing agent, 1,2,3,4,6-pentagalloyl glucose (PGG), delivered locally to the aneurysm sac, can bind to elastin and collagen to re-establish strength and resist enzymatic degradation. We aimed to demonstrate that a one-time administration of PGG solution to the aneurysm wall is safe and potentially effective to slow the growth of small- to medium-sized AAAs. MethodsPatients with small- to medium-sized infrarenal AAAs (maximum diameter <5.5 cm) were recruited. Via transfemoral access, a 14F or 16F dual-balloon delivery catheter was introduced into the aneurysm sac. A single, 3-minute, localized endoluminal infusion of PGG was delivered via a ‘weeping’ balloon to the aneurysm wall. Independent core laboratory measurements of maximum aneurysm sac diameter and sac volume measurements based on computed tomography angiography (CTA) were used for assessments at 1, 6, 12, 24, and 36 months. The primary endpoints were technical success and safety (major adverse events at 30 days). The secondary endpoint was growth stabilization, defined as freedom from aneurysm sac enlargement (diameter increase >5 mm per year or volume increase of >10% per year). ResultsTwenty patients (19 male) were enrolled at five centers from May 2019 to June 2022 (mean age, 67.8 years; range, 50-87 years). All procedures were technically successful. The safety profile was consistent with standard interventional procedures. Four patients demonstrated transient elevations of liver enzymes levels that returned to normal by 30 days with no clinical symptoms. Through November 2022, follow-up CTA data is available on the first 11 patients. The average changes in maximum aneurysm diameter from baseline to 6, 12, 24, and 36 months were 0.2 mm, 1.1 mm, 1.2 mm, and 0.8 mm, respectively, and the average changes in volume were 2.0%, 9.6%, 18.1%, and 11.6%, respectively. At 12 months, none of the aneurysms showed growth >5.0 mm, and three had volume growth >10%. ConclusionsThe early results of this first-in-human, small cohort study demonstrated that a single, localized PGG administration to patients with small- to medium-sized infrarenal AAAs is safe. Longer term follow-up on all 20 treated patients is needed to better assess the potential impact on aneurysm growth.

FOLLOW-UP OF VASCULAR LESIONS IN FIBROMUSCULAR DYSPLASIA. NO EVIDENCE FOR PROGRESSION YET

Objective: It is currently unknown whether the vascular lesions in patients with fibromuscular dysplasia (FMD) are progressive in time. Therefore, repeat CT-angiography (CTA) is often necessary to evaluate possible evolution of the abnormalites. It would be unjustified to frequently expose patients to this diagnostic modality with its drawbacks (radiation, contrast material) if the vascular lesions turn out to be stable. The aim of our study was to explore whether vascular FMD lesions (unifocal or multifocal, with or without aneurysms) change in terms of extensiveness or localization over a period of a few years. Design and method: To qualify for the present study, patients had to be diagnosed with FMD in any vascular bed and both the diagnostic and the follow-up CTA had to be performed at the same institution using the same imaging protocol. Patients who had been referred by other hospitals and were followed in our own clinic were excluded from the analysis. On both the basal and the follow-up CTA, we assessed the number of lesions, the site of lesions, and the presence or absence of aneurysms. Results: A total of 161 patients had both a diagnostic and a follow-up CTA at our own clinic. Their mean age at diagnosis was 49 + 11 years (range 19-76) and 63% of the patients had been detected during a work-up for hypertension. On average, FMD was diagnosed nine years after the initial diagnosis of hypertension had been made. In the remainder of the patients, FMD was diagnosed after the patient had experienced a dissection (coronary, carotid). Follow-up CTA after two years was available in 111 patients and after three years in 50 patients. In only three patients we found new vascular lesions after a period of two years. In all the others, the pattern of lesions remained constant. Conclusions: Over a period of two to three years, vascular FMD lesions do not seem to progress in most patients. If repeat CTA scanning is considered, one should respect at least this time period.

Initial experience with a modified "candy-plug" technique for false lumen embolization in chronic type B aortic dissection.

Persistent distal false lumen (FL) perfusion after thoracic endovascular aortic repair (TEVAR) for type B aortic dissection (TBAD) can lead to aneurysmal degeneration and an increased risk of rupture. We have presented our initial experience using a modified "candy-plug" (CP) technique for FL embolization. From February 2021 to July 2022, we treated six patients using the modified CP technique. All the patients had undergone prior or simultaneous TEVAR for chronic TBAD with persistent FL perfusion and aneurysm expansion. Bilateral common femoral artery access was obtained, and intravascular ultrasound was used to confirm wire access in the true lumen (TL) and FL. A conformable TAG device (W.L. Gore & Associates, Flagstaff, AZ) was used in four cases and an Excluder aortic cuff (W.L. Gore & Associates) in two cases. The device was modified by placing a constraining "napkin-ring" suture through the middle segment of the device. Femoral sheaths were placed in the TL and FL. A standard TL TEVAR extension was performed at the level of the celiac artery (zone 5). Next, the CP device was advanced and deployed in the FL, distally aligning it with the TL device. An appropriately sized Amplatzer II plug (Abbot Vascular, Santa Clara, CA) was then deployed in the constrained segment of the modified stent graft. Completion angiography was performed to confirm successful FL embolization. Technical success was defined as successful deployment of the CP device in the FL. The technical success rate was 100% (six of six patients). Clinical success was defined as the cessation of aneurysm growth on follow-up computed tomography angiography. No 30-day mortality, myocardial infarction, stroke, spinal cord ischemia, access site complications, or aortic-related reinterventions occurred. Surveillance imaging at a mean follow-up of 10months confirmed clinical success (stable aneurysm size or shrinkage) for all five patients with follow-up data available. The modified CP embolization technique is a promising solution for persistent distal FL perfusion after TEVAR for TBAD. Further investigation is required to determine the long-term durability of this technique as an adjunct to TEVAR to promote aortic remodeling.