Employing magnetic resonance histology for precision chronic limb-threatening ischemia treatment planning.

OBJECTIVE: Recent randomized controlled trials have demonstrated a notable prevalence of immediate technical failures in percutaneous vascular interventions (PVIs) for complex arterial lesions associated with chronic limb-threatening ischemia. Current imaging modalities present inherent limitations in identifying these lesions, making it challenging to determine the most suitable candidates for PVI. We present a novel preprocedural magnetic resonance imaging (MRI) histology protocol for identifying lesions that might present a higher rate of immediate and midterm PVI failure. METHODS: We enrolled 22 patients (13 females, average age 65.8 ± 9.72 years) scheduled for PVI were prospectively and underwent 3T MRI using ultrashort echo time and steady-state free precession contrasts to characterize target lesions before PVI. Lesions were scored as hard if >50% of the lumen was occluded by hard components (calcium/dense collagen) on MRI in the hardest cross-section. Two readers evaluated MRI datasets. Trans-Atlantic Inter-Society Consensus Document on Management of Peripheral Arterial Disease (TASC)/Global Limb Anatomic Staging System (GLASS)/Wound, Ischemia and Foot infection scoring was performed based on intraprocedural angiograms and chart review. The relationship between MRI scoring, TASC/GLASS scoring, and procedural outcomes was investigated using univariate analysis. Midterm follow-up (revascularization and amputation rates) was recorded at 3 and 6 months after the intervention. RESULTS: Our cohort of 22 patients yielded 40 target lesions. Five lesions were excluded (two for nondiagnostic image quality; three PVIs were ultimately diagnostic only). Six lesions (17%) were scored as hard. MRI-scored hard lesions had a higher proportion of immediate technical failure (hard vs soft 83% [5/6] vs 3% [1/29]; P < .001). Hard vs soft MRI scoring was the only factor significantly associated with immediate PVI technical success (P < .001), as opposed to TASC/GLASS scoring. Both at 3 months and 6 months after PVI, the reintervention rate was significantly higher among those lesions which were scored hard on MRI (3 months hard, 80% vs soft, 16% [P =.011]; 6 months hard, 80% vs soft, 27%; P = .047). CONCLUSIONS: MRI histology could be a valuable tool for optimizing PVI patient selection and treatment strategies.

Percutaneous Cannulation of the Axillary Artery: Does the Position of the Brachial Plexus Correlate With Bony Landmarks That Could Be Used to Reduce the Risk of Complications?

Introduction Endovascular surgery is an innovative way of carrying out procedures such as transcatheter aortic valve insertion where the femoral artery is commonly used as an access point. Conditions like peripheral arterial disease can make endovascular procedures challenging when atherosclerotic plaques compromise the integrity of lower limb vessels. An alternative access point for these patients is required. Access through the axillary artery has been proposed; however, the close proximity of the brachial plexus introduces a risk of neural complications. This study aims to find an anatomical or bony landmark(s) to help identify an area of safety on the axillary artery that can be used to gain access. Materials and methods Nine cadavers were used in the study and five parameters were measured using the acromion and coracoid processes as bony landmarks. The 1st parameter measured the distance between the acromion and the coracoid process. The 2nd parameter was the diameter of the axillary artery taken at a plane extending from the acromion to the coracoid process - now defined as the coracoacromial plane. The 3rd measurement was the distance between the coracoid process and the midpoint of the axillary artery diameter taken at the above plane; it is proposed this will form a safe point on the axillary artery. The 4th parameter measured was the distance between the safe point on the axillary artery and the median nerve. The 5th parameter was the distance between the safe point and the thoracoacromial trunk. Measurements were taken using digital callipers and were recorded for both sides of the cadaver except for one. Using the data from the measurements, an area of safety was calculated and statistical analysis was carried out using Student's t-test and Pearson's correlation to look for significant differences between the left and right sides. Results The mean distance from the safe point of the axillary artery to the median nerve was 23.25 mm on the left and 27.10 mm on the right. The p-value was 0.7, which indicated no significant differences between both sides. The mean distance between the safe point and the thoracoacromial trunk was 11.31 mm on the left and 13.21 mm on the right. The p-value was 0.24, indicating no significant differences between both sides. The mean area of safety was larger on the right side with an area of 184.37 mm and smaller on the left side with an area of 158.93 mm. The p-value was 0.62, which indicated no significant differences between both sides. There was no clear relationship between the distance from the acromion to the coracoid process compared to the distance between the acromion and a defined safe point on the axillary artery. This was confirmed using a Pearson's correlation test, which resulted in a p-value of 0.53 on the left and 0.93 on the right. These values were above the critical value, suggesting no correlation. Conclusion The acromion and the coracoid process are important bony landmarks that can be used to define the coracoacromial plane that traverses the axillary artery whereby avoiding the cords of the brachial plexus, the median nerve as well as the thoracoacromial trunk. Implementing this approach to define a safe vascular access point on the axillary artery could minimise complications like brachial plexus injuries. Further studies on a larger sample size using radiological methods may need to be carried out to help increase confidence in these preliminary cadaveric findings.

Radial artery access with a sheathless 0.087" inner diameter balloon guide catheter (Walrus) for neurointerventional procedures: Technique and clinical outcomes.

Intro: There is a growing preference among neurointerventionalists for transradial access (TRA) over transfemoral access (TFA) due to improved patient satisfaction, recovery time and reduced access site complication, but using balloon guide catheters (BGCs) in the radial artery remains a challenge. We report our experience in successfully using the 0.087" inner diameter Walrus BGC without a sheath via the radial artery for non-emergent neurointerventions. Objective: Describe the technique for safely accessing the radial artery using the sheathless Walrus balloon guide catheter. Methods: A retrospective chart review of thirteen consecutive patients who underwent intervention with radial artery access with a sheathless Walrus BGC was performed. Results: All twelve procedures were performed successfully with no instances of conversion from TRA to TFA. There were no significant procedural or access site complications. The mean radial diameter was 2.51 mm. Conclusions: The Walrus 0.087" ID BGC is an effective tool that can safely be used via the radial artery using a sheathless approach, which helps to maximize the size of the catheter that can be used. This is the first instance of our knowledge of this technique being utilized for neurointerventions and therefore could be used to expand the indications for TRA for a wider range of procedures.

Arterial spin labeling detects trapped labeled spins in flow-diverted aneurysms and it reflects intra-aneurysmal flow stasis.

BACKGROUND: This study evaluated arterial spin labeling (ASL) imaging findings in flow-diverted aneurysms (FD-ANs). METHODS: Twenty-one patients with internal carotid artery aneurysms treated with flow-diverter stent (FDS) were included. Time-of-flight magnetic resonance angiography (TOF-MRA) and ASL were performed before and after follow-up digital subtraction angiography (DSA) on the day, 6 months, and/or 1 year after treatment. Two radiologists rated the clarity of the depiction of FD-ANs for MRA on a 3-point scale and the ASL signal intensity of the aneurysm as negative or positive. A neurosurgeon assessed DSA findings using the O'Kelly-Marotta (OKM) grading scale, categorizing them into filling and stasis grades. The 23 examinations were classified according to the OKM grading scale, and the proportion of ASL-positive cases and the proportion of cases with MRA scores of 1-2 (detectable) were calculated for each grade. The relationship between the OKM grading scale and ASL positivity or MRA detectable was examined using Fisher's exact test. RESULTS: Of seven examinations where the statis grade was 1 or 2, no examinations showed ASL positivity. However, among the 16 examinations in which the stasis grade was 3, 9 examinations showed ASL positivity. A significant association was observed between stasis grade and ASL positivity (p = 0.035). In contrast, no significant relationship was observed between the OKM grading scale and the MRA 3-point scale. CONCLUSION: High-signal ASL in FD-ANs could reflect stasis within the aneurysm; therefore, noninvasive ASL can indicate reduction in intra-aneurysmal blood flow after treatment and reperfusion during posttreatment observation.

Endovascular Treatment versus Open Surgical Repair for Isolated Iliac Artery Aneurysms.

Purpose: Endovascular treatment (EVT) has been shown to be effective and safe for isolated iliac artery aneurysms (IAAs). However, concerns remain regarding the lack of consideration to recent advances in perioperative care and surgical techniques, as well as a significant number of re-interventions with EVT. This study compares the outcomes of open surgical repair (OSR) and EVT using recent clinical data. Materials and Methods: This retrospective, single-center study included patients who underwent OSR or EVT for isolated degenerative IAAs between January 2007 and December 2018. Primary outcomes were procedure time, number of transfusions during admission, length of hospital stay, complications, and number of preserved internal iliac arteries. Secondary outcomes included all-cause and aneurysm-related mortality, and re-intervention rates. Results: Fifty-eight consecutive patients underwent treatment for isolated IAAs (25 underwent OSR and 33 underwent EVT), with a median follow-up of 75 months (range: 39-133 months). Baseline characteristics were similar between the groups, except for a lower mean age in the OSR group than in the EVT group (66.0±8.2 vs. 73.1±8.6, P=0.003). Both groups had a mild risk of comorbidity severity score. Early complications (within 30 days of the procedure) occurred more frequently in the OSR group, though not statistically significant (24.0% vs. 6.1%, P=0.07). Late complications, including sac expansion and thrombotic occlusion, were significantly more common in the EVT group (15.2% vs. 0%, P=0.04). Re-intervention rate was higher in the EVT group but not statistically significant (9.1% vs. 4.0%, P=0.44). No significant differences were observed in major adverse cardiovascular events and mortality between the groups (P=0.66 and P=0.27), and there were no aneurysm-related deaths. Conclusion: For patients with mild risk factors, EVT does not offer a survival or re-intervention advantages over OSR in the treatment of isolated IAAs. However, EVT is associated with an increased risk of late complications. Although larger randomized studies are necessary, OSR may be considered the first-line treatment for isolated IAAs in younger and mild-risk patients.

Thoracic Endovascular Aortic Repair and Endovascular Aneurysm Repair Approaches for Managing Aortic Pathologies: A Retrospective Cohort Study.

Background/Objectives: Since thoracic endovascular aortic repair (TEVAR) and endovascular aneurysm repair (EVAR) are increasingly utilized, examining their outcomes and safety in real-world scenarios is crucial. This study investigated the management and outcomes of TEVAR and EVAR as alternatives to traditional open surgical repair for managing aortic pathologies. Methods: This was a retrospective cohort study. We analyzed the data from 59 consecutive patients who underwent TEVAR or EVAR between 2015 and 2022 at a single tertiary care center. The primary outcome was survival, and secondary outcomes were complications assessment, including re-intervention and occurrence of endoleaks. Results: TEVAR accounted for 47.5% of cases (n = 28), while EVAR comprised 52.5% (n = 31). Patients were mostly 61-70 years old (23.7%) and male (91.5%). Surgery indications differed, with aneurysmal repair being the prevalent indication for EVAR (90.3%, n = 28) and trauma being the main indication for TEVAR (67.9%, n = 19). Regarding the primary outcome, 11 patients (18.6%) died for various reasons; of those, 2 patients (3.4%) were determined to have died from vascular-related issues. Most patients (81.4%, n = 48) did not experience intraoperative complications. The most common intraoperative complications were endoleaks and access failure, each affecting 5.1% (n = 3) of patients. Re-intervention was necessary in 16.9% (n = 10) of cases, with endoleaks being the major indication (60%). Emergency intervention was more frequent in the TEVAR group (p = 0.013), resulting in significantly longer hospitalization (p = 0.012). Conclusions: Despite limitations, our analysis indicates a good safety profile with high success rates and a low incidence of adverse health outcomes and mortality in TEVAR/EVAR procedures. Nevertheless, the results emphasize the ongoing concern of endograft leaks, necessitating re-interventions.

The Gore Viabahn balloon-expandable stent graft as a bridging stent in complex endovascular aortic procedures at 3 years performs better in fenestrations.

OBJECTIVE: Complex endovascular procedures are now recognized as the gold standard treatments for extensive aortic diseases. Bridging stents (covered stents used to couple the aortic graft to the visceral vessels) play a pivotal role, yet there is currently no dedicated device available on the market. The aim of the study was to evaluate the midterm performance of the Gore Viabahn balloon-expandable (VBX) stent graft as a bridging stent for target visceral vessels (TVVs). METHODS: Data from all consecutive patients who underwent a fenestrated and branched endovascular aortic repair and received the VBX stent graft as a bridging stent between July 2018 and September 2022 were prospectively collected and subsequently analyzed retrospectively. Primary end points included freedom from TVV instability and freedom from TVV-related reinterventions, both overall and in comparison between branched and fenestrated graft configurations. Secondary end points were overall survival, procedure and TVV-related (in an intent-to-treat basis) technical success, freedom from type IC/IIIC endoleak, and freedom from TVV patency loss. RESULTS: Sixty-three patients were treated with a fenestrated and branched endovascular aortic repair using the VBX stent graft as a bridging stent, of whom 47 (74.6%) presented an atherosclerotic aneurysm, 7 (11.1%) a post-dissecative aneurysm, and 9 (14.3%) an anastomotic pseudoaneursym or a type IA endoleak in a previous endovascular aortic repair. Included in the aortic repair were 231 of 243 (95.1%) total visceral vessels. The intraoperative requirement of 13 additional VBX stent grafts determined a TVV-related technical success of 94.4%. The mean follow-up was 26.1 ± 16.4 months. The estimated overall survival at 36 months was 73% ± 7.5%. The estimated rates at 36 months for freedom from type IC/IIIC endoleaks and TVV primary patency were 90.6% ± 3.9% and 99% ± 0.7%, respectively. The estimated rate at 36 months for freedom from TVV instability was 92.1% ± 3% and did not differ between branched and fenestrated configurations, whereas freedom from TVV-related reinterventions was 90.6% ± 3.1% and significantly in favor of fenestrations (69.4% vs 96.8%, P < .001). Multivariate analyses confirmed fenestrated configuration as a protective factor against TVV-related reinterventions (hazard ratio: 0.079; 95% confidence interval: 0.016-0.403). CONCLUSIONS: The VBX stent graft proves to be a reliable bridging stent for complex aortic procedures involving both fenestrated and branched endografts. Although immediate results are deemed satisfactory, they favor fenestrations regarding the need of reinterventions through 3 years. The success of the procedure heavily relies on a thorough understanding of the unique characteristics of this stent.

Outcomes following carotid revascularization in patients with prior ipsilateral carotid artery stenting in the Vascular Quality Initiative.

OBJECTIVE: The outcomes of carotid revascularization in patients with prior carotid artery stenting (CAS) remain understudied. Prior research has not reported the outcomes after transcarotid artery revascularization (TCAR) in patients with previous CAS. In this study, we compared the peri-operative outcomes of TCAR, transfemoral CAS (tfCAS) and carotid endarterectomy (CEA) in patients with prior ipsilateral CAS using the Vascular Quality Iniatitive. METHODS: Using Vascular Quality Initiative data from 2016 to 2023, we identified patients who underwent TCAR, tfCAS, or CEA after prior ipsilateral CAS. We included covariates such as age, race, sex, body mass index, comorbidities (hypertension, diabetes, prior coronary artery disease, prior coronary artery bypass grafting/percutaneous coronary intervention, congestive heart failure, renal dysfunction, smoking, chronic obstructive pulmonary disease, and anemia), symptom status, urgency, ipsilateral stenosis, and contralateral occlusion into a regression model to compute propensity scores for treatment assignment. We then used the propensity scores for inverse probability weighting and weighted logistic regression to compare in-hospital stroke, in-hospital death, stroke/death, postoperative myocardial infarction (MI), stroke/death/MI, 30-day mortality, and cranial nerve injury (CNI) after TCAR, tfCAS, and CEA. We also analyzed trends in the proportions of patients undergoing the three revascularization procedures over time using Cochrane-Armitage trend testing. RESULTS: We identified 2137 patients undergoing revascularization after prior ipsilateral carotid stenting: 668 TCAR patients (31%), 1128 tfCAS patients (53%), and 341 CEA patients (16%). In asymptomatic patients, TCAR was associated with a lower yet not statistically significant in-hospital stroke/death than tfCAS (TCAR vs tfCAS: 0.7% vs 2.0%; adjusted odds ratio [aOR], 0.33; 95% confidence interval [CI], 0.11-1.05; P = .06), and similar odds of stroke/death with CEA (TCAR vs CEA: 0.7% vs 0.9%; aOR, 0.80; 95% CI, 0.16-3.98; P = .8). Compared with CEA, TCAR was associated with lower odds of postoperative MI (0.1% vs 14%; aOR, 0.02; 95% CI, 0.00-0.10; P < .001), stroke/death/MI (0.8% vs 15%; aOR, 0.05; 95% CI, 0.01-0.25; P < .001), and CNI (0.1% vs 3.8%; aOR, 0.04; 95% CI, 0.00-0.30; P = .002) in this patient population. In symptomatic patients, TCAR had an unacceptably elevated in-hospital stroke/death rate of 5.1%, with lower rates of CNI than CEA. We also found an increasing trend in the proportion of patients undergoing TCAR following prior ipsilateral carotid stenting (2016 to 2023: 14% to 41%), with a relative decrease in proportions of tfCAS (61% to 45%) and CEA (25% to 14%) (P < .001). CONCLUSIONS: In asymptomatic patients with prior ipsilateral CAS, TCAR was associated with lower odds of in-hospital stroke/death compared with tfCAS, with comparable stroke/death but lower postoperative MI and CNI rates compared with CEA. In symptomatic patients, TCAR was associated with unacceptably higher in-hospital stroke/death rates. In line with the postprocedure outcomes, there has been a steady increase in the proportion of patients with prior ipsilateral stenting undergoing TCAR over time.

Beyond Abdominal Pain: Decoding the Mysteries of Nutcracker Syndrome.

Nutcracker syndrome (NCS), a rare but impactful vascular condition, emerges from the compression of the left renal vein by adjacent major arteries, leading to a diverse array of symptoms such as hematuria, flank pain, and renal challenges. Highlighting the case of a 30-year-old male with an atypical presentation of NCS, this report explores the diagnostic complexities arising from its varied presentations and therapeutic options. It emphasizes the critical role of computed tomography (CT) in unveiling the underlying vascular constriction. Through this lens, the case underscores the necessity of considering NCS in the differential diagnosis of abdominal pain, advocating for a prompt and accurate diagnosis to guide effective management strategies, ranging from conservative approaches to surgical intervention. This stresses the importance of heightened awareness and ongoing research for optimizing patient outcomes in the face of this elusive condition.

Analysis of the current usage of resuscitative endovascular balloon occlusion of the aorta (REBOA) in pediatric trauma patients: a retrospective observational study from the American College of Surgeons-Trauma Quality Improvement Program databases.

Background: Resuscitative endovascular balloon occlusion of the aorta (REBOA) has been an established life-saving procedure for adult trauma patients, but the evidence for its use in pediatric patients is still under question. The purpose of this study was to examine the outcome of REBOA in pediatric patients. Methods: We retrospectively analyzed observational cohort data from the American College of Surgeons-Trauma Quality Improvement Program from 2017 to 2019. We analyzed 183 506 trauma patients aged 7-18, and 111 patients were matched by propensity score analysis. Basic demographics, injury severity, trauma type, and clinical outcomes of the patients receiving REBOA and those not receiving REBOA were compared. In the REBOA patients, a subgroup analysis was performed to evaluate the potential influence of age and body weight on the outcomes of REBOA. Results: After the pretreatment factors were balanced for the REBOA and no-REBOA groups, the patients in the REBOA group had more transfused packed red blood cells within the first 4 hours (3250 mL vs. 600 mL, p<0.001), and the mortality rate was higher in the REBOA group, but it did not reach statistical significance (56.8% vs. 36.5%, p=0.067). No significant difference was detected regarding in-hospital complications. In the subgroup analysis of the patients who received REBOA, we discovered no significant difference in mortality and complications between the subgroups when compared by age (>15 years old/≤15 years old) or weight (>58 kg or ≤58 kg). Conclusions: Pediatric trauma patients who received REBOA were not significantly associated with an increased risk of mortality when compared with no-REBOA patients with matched basic demographics and pretreatment factors. Younger age and lighter body weight did not seem to influence the outcomes of REBOA regarding survival and complications. Level of evidence: Level III.

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.

ALARA principles in practice: reduced frame and pulse rates for middle meningeal artery embolization.

Objective: As the prevalence of neuroendovascular interventions increases, it is critical to mitigate unnecessary radiation for patients, providers, and health care staff. Our group previously demonstrated reduced radiation dose and exposure during diagnostic angiography by reducing the default pulse and frame rates. We applied the same technique for basic neuroendovascular interventions. Methods: We performed a retrospective review of prospectively acquired data after implementing a quality improvement protocol in which pulse rate and frame rate were reduced from 15 p/s to 7.5 p/s and 7.5 f/s to 4.0 f/s respectively. We studied consecutive, unilateral middle meningeal artery embolizations treated with particles. Total radiation dose, radiation per angiographic run, total radiation exposure, and exposure per run were calculated. Multivariable log-linear regression was performed to account for patient body mass index (BMI), number of angiographic runs, and number of vessels catheterized. Results: A total of 20 consecutive, unilateral middle meningeal artery embolizations were retrospectively analyzed. The radiation reduction protocol was associated with a 39.2% decrease in the total radiation dose and a 37.1% decrease in radiation dose per run. The protocol was associated with a 41.6% decrease in the total radiation exposure and a 39.5% decrease in exposure per run. Conclusions: Radiation reduction protocols can be readily applied to neuroendovascular interventions without increasing overall fluoroscopy time and reduce radiation dose and exposure by 39.2% and 41.6% respectively. We strongly encourage all interventionalists to be cognizant of pulse rate and frame rate when performing routine interventions.

Six-Year Outcomes of Total Arch Replacement vs Debranching With TEVAR for Aortic Arch Pathologies: Meta-Analysis of Kaplan-Meier-Derived Data From Propensity Score-Matched Studies.

BACKGROUND: Total arch replacement (TAR) and debranching plus thoracic endovascular aortic repair (TEVAR) serve as significant therapeutic options for aortic arch pathologies. It remains unclear whether one of these approaches should be considered preferable. Our study aimed to compare the long-term outcomes of these 2 approaches. METHODS: We carried out a pooled meta-analysis of time-to-event data extracted from studies published by December 2023. Eligibility criteria included populations with any aortic arch pathology who underwent debranching plus TEVAR or TAR, propensity score-matched (PSM) studies (prospective/retrospective; single-center/multicentric), and the outcomes included follow-up for overall survival/mortality and/or reinterventions. RESULTS: Eleven PSM studies met our eligibility criteria, including a total of 1142 patients (571 matched pairs). We did not observe any statistically significant difference in the risk of all-cause death between the groups (hazard ratio [HR]=1.20, 95% confidence interval [CI]=0.91-1.56, p=0.202), but patients who underwent TAR had a significantly lower risk of late aortic reinterventions compared with patients who underwent debranching plus TEVAR (HR=0.38, 95% CI=0.23-0.64, p<0.001). Our meta-regression analyses for all-cause mortality identified statistically significant coefficients for age (coefficient=-0.047; p=0.012) and type A aortic dissections (coefficient=0.012; p=0.010). CONCLUSIONS: Debranching plus TEVAR and TAR demonstrate no statistically significant differences in terms of survival in patients with aortic arch pathologies, but TAR is associated with lower risk of late aortic reinterventions over time. Although older patients may benefit more from debranching plus TEVAR rather than from TAR, patients with dissections may benefit more from TAR. CLINICAL IMPACT: Although the 2 strategies seem to be equally valuable in terms of survival, total aortic arch replacement (when compared with debranching plus TEVAR to treat patients with aortic arch pathologies) is associated with reduction of late aortic reinterventions over time in patients with and without aortic dissections. However, we should consider debranching plus TEVAR in older patients as it is associated with lower risk of death in this population. The novelty of our study lies in the fact that, instead of comparing study-level effect estimates, we analyzed the outcomes with reconstructed time-to-event data. This offered us the opportunity of performing our analyses with a mathematically appropriate model which consider events and time; however, these findings might be under the influence of treatment allocation bias.

Clearance rate of contrast extravasation after endovascular therapy is associated with functional outcome and mediated by cerebral edema.

The brain's function of clearance and transport is closely related to the prognosis of acute ischemic stroke (AIS). In this study, we proposed a novel method, clearance rate of contrast extravasation (CROCE), to measure brain clearance and transport function in AIS patients undergoing endovascular therapy (EVT), and examined its association with cerebral edema and functional outcome. We conducted a pooled analysis of AIS patients of anterior circulation large vessel occlusion who underwent EVT in two academic hospitals. Patients who experienced contrast extravasation but not intracerebral hemorrhage following EVT were included. CROCE was defined as the mass of contrast agent cleared per hour on non-contrast CT (NCCT). Among the 215 patients finally included, we found that high CROCE was significantly associated with 90-day favorable functional outcome, and the association retained after adjustment for potential confounders. Different correlation analysis demonstrated a significant correlation between CROCE, cerebral edema, and functional outcome. Further mediation analysis revealed that cerebral edema mediated the effect of CROCE on functional outcome. These results revealed that CROCE may be a promising indicator of brain clearance function for patients who received EVT and had contrast extravasation.

An in-vitro method for comparative analysis of aspiration catheter tracking performance.

BACKGROUND AND PURPOSE: Mechanical thrombectomy (MT) for acute ischemic stroke (AIS) relies on efficient tracking of aspiration catheters through complex vascular anatomies. Differences in catheter design lead to variation in tracking performance which may only become apparent after use in patients. We developed an in-vitro methodology for evaluating aspiration catheter performance under a variety of pre-defined circumstances, that can be used during catheter development for design optimization. METHODS: Validation of the in-vitro methodology involved testing four large bore aspiration catheters on recreated challenging vascular access routes derived from patient angiograms. Two experienced neurointerventionalists conducted the tests under controlled physiological and procedural conditions. Each catheter design was evaluated across 30 unique anatomy-procedural set-up combinations. A fifth, prototype large bore catheter was evaluated by trained engineers to assess the applicability of the in-vitro test. RESULTS: Results from statistical analysis using a general linear model demonstrated the methodology's effectiveness in detecting significant tracking differences among catheter designs (p < 0.01). Minimal inter-operator variability was observed (p = 0.304), while procedural techniques significantly influenced tracking performance (p < 0.01). The tortuosity of the arterial access route notably impacted catheter performance (p < 0.01), with anatomical features revealing varying degrees of influence on desirable and undesirable catheter design aspects. CONCLUSION: We successfully developed a test methodology for evaluating the trackability of large bore aspiration catheters intended for treating acute ischemic stroke with large vessel occlusions. This methodology offers a robust approach to pre-clinical design assessment, utilizing anatomical models that simulate real-world vascular challenges to enhance catheter optimization.

Vessel-based CTA-image to spatial anatomy registration using tracked catheter position data: preclinical evaluation of in vivo accuracy.

Electromagnetic tracking of endovascular instruments has the potential to substantially decrease radiation exposure of patients and personnel. In this study, we evaluated the in vivo accuracy of a vessel-based method to register preoperative computed tomography angiography (CTA) images to physical coordinates using an electromagnetically tracked guidewire. Centerlines of the aortoiliac arteries were extracted from preoperative CTA acquired from five swine. Intravascular positions were obtained from an electromagnetically tracked guidewire. An iterative-closest-point algorithm registered the position data to the preoperative image centerlines. To evaluate the registration accuracy, a guidewire was placed inside the superior mesenteric, left and right renal arteries under fluoroscopic guidance. Position data was acquired with electromagnetic tracking as the guidewire was pulled into the aorta. The resulting measured positions were compared to the corresponding ostia manually identified in the CTA images after applying the registration. The three-dimensional (3D) Euclidean distances were calculated between each corresponding ostial point, and the root mean square (RMS) was calculated for each registration. The median 3D RMS for all registrations was 4.82 mm, with an interquartile range of 3.53-6.14 mm. A vessel-based registration of CTA images to vascular anatomy is possible with acceptable accuracy and encourages further clinical testing. RELEVANCE STATEMENT: This study shows that the centerline algorithm can be used to register preoperative CTA images to vascular anatomy, with the potential to further reduce ionizing radiation exposure during vascular procedures. KEY POINTS: Preoperative images can be used to guide the procedure without ionizing intraoperative imaging. Preoperative imaging can be the only imaging modality used for guidance of vascular procedures. No need to use external fiducial markers to register/match images and spatial anatomy. Acceptable accuracy can be achieved for navigation in a preclinical setting.

Endovascular Treatment for Renal Vein Embolism by a Renal Calculus After Percutaneous Nephrolithotomy.

PURPOSE: This report presents the endovascular strategies adopted to treat a kidney calculus venous embolism after percutaneous nephrolithotomy and the versatility of endovascular techniques to manage even the most unexpected renovascular complications after urological intervention. According to the literature available in PubMed, Cochrane, SciELO, and Science.gov repositories, this is the first case to our knowledge of renal vein calculus embolism as a complication of percutaneous treatment of kidney stones. CASE REPORT: A 62-year-old woman underwent percutaneous nephrolithotomy to treat a left kidney 2.8-cm staghorn calculi. The stone cracked, leaving a residual fragment in the ureteropelvic junction. Abdominal computed tomography revealed a 0.9-mm extrarenal calculus located inside the left retroaortic renal vein. Calculus was captured using a basket catheter system through a 6F 45-cm sheath positioned in the left common femoral vein (CFV) and accessed by dissection to safely conclude the calculus extraction by venous cut down. The patient was asymptomatically discharged 48 hours after the endovascular procedure, under a rivaroxaban anticoagulation regimen, with no symptoms or renal function impairment until the 6 months of follow-up. CONCLUSION: The endovascular strategy proposed in this case was effective for calculus rescue and venous flow restoration. CLINICAL IMPACT: This case reinforces the adaptability of endovascular therapy in an unexpected scenario. A potentially life-threatening extremely rare adverse event following a common urological procedure could be treated with minimally invasive hybrid treatment, preserving renal function and maintaining venous vascular patency. This report may add a discussion of procedures to manage similar events and bring to the literature a possible strategy to solve the problem.