fMRI of Working Memory Impairment after Recovery from Subarachnoid Hemorrhage

Recovery from aneurysmal subarachnoid hemorrhage (SAH) is often incomplete and accompanied by subtle but persistent cognitive deficits. Previous neuropsychological reports indicate these deficits include most prominently memory impairment, with working memory particularly affected. The neural basis of these memory deficits remains unknown and unexplored by functional magnetic resonance imaging (fMRI). In the present study, patients who experienced (SAH) underwent fMRI during the performance of a verbal working memory paradigm. Behavioral results indicated a subtle but statistically significant impairment relative to healthy subjects in working memory performance accuracy, which was accompanied by relatively increased blood-oxygen level dependent signal in widespread left and right hemisphere cortical areas during periods of encoding, maintenance, and retrieval. Activity increases remained after factoring out inter-individual differences in age and task performance, and included most notably left hemisphere regions associated with phonological loop processing, bilateral sensorimotor regions, and right hemisphere dorsolateral prefrontal cortex. We conclude that deficits in verbal working memory following recovery from (SAH) are accompanied by widespread differences in hemodynamic correlates of neural activity. These differences are discussed with respect to the immediate and delayed focal and global brain damage that can occur following (SAH), and the possibility that this damage induces subcortical disconnection and subsequent decreased efficiency in neural processing

Optimising surveillance and re-intervention strategy following elective endovascular repair of abdominal aortic aneurysms

Background Elective endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm has an initial survival advantage over open repair (OR), but more frequent complications increase costs and long-term aneurysm-related mortality. Randomised controlled trials of EVAR versus OR have shown EVAR is not cost-effective over a patient’s lifetime. However, in the EVAR-1 trial, post-operative surveillance may have been sub-optimal, as the importance of sac growth as a predictor of graft failure was overlooked. Methods Real-world data informed a discrete event simulation model of post-operative outcomes following EVAR. Outcomes observed EVAR-1 were compared with those from five alternative post-operative surveillance and re-intervention strategies. Key events, quality-adjusted life years and costs were predicted. The impact of using complication and rupture rates from more recent devices, imaging and re-intervention methods was also explored. Results Compared with observed EVAR-1 outcomes, modelling full adherence to the EVAR-1 scan protocol reduced AAA deaths by 3% and increased elective re-interventions by 44%. European Society re-intervention guidelines provided the most clinically effective strategy, with an 8% reduction in AAA deaths, but a 52% increase in elective re-interventions. The cheapest and most cost-effective strategy used lifetime annual ultrasound in primary care with confirmatory CT if necessary, and reduced AAA-related deaths by 5%. Using contemporary rates for complications and rupture did not alter these conclusions. Conclusions All alternative strategies improved clinical benefits compared with the EVAR-1 trial. Further work is needed regarding the cost and accuracy of primary care ultrasound, and the potential impact of these strategies in the comparison with OR.Financial support from National Institute of Health Research and Camelia Botnar Arterial Foundation. The National Institute of Health Research (NIHR) had no role in study design, data collection, data analysis, data interpretation, in the writing of the report or in the decision to submit the article for publication. The views and opinions expressed herein are those of the authors and do not necessarily reflect those of the NIHR, UK NHS, or Department of Health. The corresponding author had full access to all the data in the study and had final responsibility for the decision to submit for publication

Optimizing Surveillance and Re-intervention Strategy Following Elective Endovascular Repair of Abdominal Aortic Aneurysms

Background: EVAR for abdominal aortic aneurysm has an initial survival advantage over OR, but more frequent complications increase costs and long-term aneurysm-related mortality. Randomized controlled trials of EVAR versus OR have shown EVAR is not cost-effective over a patient's lifetime. However, in the EVAR-1 trial, postoperative surveillance may have been sub-optimal, as the importance of sac growth as a predictor of graft failure was overlooked. Methods: Real-world data informed a discrete event simulation model of postoperative outcomes following EVAR. Outcomes observed EVAR-1 were compared with those from 5 alternative postoperative surveillance and reintervention strategies. Key events, quality-adjusted life years and costs were predicted. The impact of using complication and rupture rates from more recent devices, imaging and re-intervention methods was also explored. Results: Compared with observed EVAR-1 outcomes, modeling full adherence to the EVAR-1 scan protocol reduced abdominal aortic aneurysm (AAA) deaths by 3% and increased elective re-interventions by 44%. European Society re-intervention guidelines provided the most clinically effective strategy, with an 8% reduction in AAA deaths, but a 52% increase in elective re-interventions. The cheapest and most cost-effective strategy used lifetime annual ultrasound in primary care with confirmatory computed tomography if necessary, and reduced AAA-related deaths by 5%. Using contemporary rates for complications and rupture did not alter these conclusions. Conclusions: All alternative strategies improved clinical benefits compared with the EVAR-1 trial. Further work is needed regarding the cost and accuracy of primary care ultrasound, and the potential impact of these strategies in the comparison with OR.Peer reviewe

Urgent and emergent repair of complex aortic aneurysms using an off-the-shelf branched device

IntroductionEndovascular repair using off-the-shelf endografts is a viable solution in patients with ruptured or symptomatic complex aortic aneurysms. This analysis aimed to present the peri-operative and follow-up outcomes in urgent and emergent cases managed with the t-Branch multibranched thoracoabdominal endograft.MethodsProspectively collected data from all consecutive urgent and emergent cases managed in two aortic centers between January 1st, 2014, to November 30th, 2022, using the t-Branch device (Cook Medical Inc., Bjaeverskov, Denmark) were analyzed. Patients presenting with ruptured aortic complex aneurysms were characterized as emergent and patients with aneurysms >90 mm of diameter, or symptomatic aneurysms were characterized as urgent. Technical success, 30-day mortality, major adverse events (MAE) and spinal cord ischemia (SCI) rates were assessed.Results225 patients (36.5% females, 72.5 ± 2.8 years) were included; 73.0% were urgent. The mean aneurysm diameter was 109 ± 3.9 mm and 44.4% were type I–III TAAAs. Females (p = .03), para-renal aneurysms (p = .02) and ASA score IV (p < .001) were more common in emergent cases. Technical success was 97.8%. Thirty-day mortality and MAE rates were 17.8% and 30.6%, respectively. SCI rate was 14.7%, (4.8% paraplegia rate) with 22.2% of patients receiving prophylactic cerebrospinal drainage. Thirty-day mortality (13.3% vs. 26.7%, p = .04) and MAE (26.0% vs. 43.0%, p = .02) were more common among emergent cases while technical success (97.6% vs. 98.3%, p = .9), and SCI (13.3% vs. 18.3%, p = .4) were similar. Survival at 12-months was 83.5% (SE 5.9%) for the urgent and 77.1% (SE 8.2%) for the emergent group (log rank, p = 0.96).ConclusionT-Branch represents an effective and safe solution for the management of urgent and emergent cases with complex aortic aneurysms, with high technical success, promising early mortality and SCI rates

Predicting risk of rupture and rupture-preventing re-interventions utilising repeated measures on aneurysm sac diameter following endovascular abdominal aortic aneurysm repair

Clinical and imaging surveillance practices following endovascular aneurysm repair (EVAR) for intact abdominal aortic aneurysm (AAA) vary considerably and compliance with recommended lifelong surveillance is poor. This study developed a dynamic prognostic model to enable stratification of patients at risk of future secondary rupture or rupture preventing re-intervention (RPR) to enable the development of personalised surveillance intervals. Baseline data and repeat measurements of post-operative aneurysm sac diameter from the EVAR-1 and EVAR-2 trials were used to develop the model with external validation in a cohort from Helsinki. Longitudinal mixed-effects models were fitted to trajectories of sac diameter and model-predicted sac diameter and rate of growth were used in prognostic Cox proportional hazards models. 785 patients from the EVAR trials were included of which 155 (20%) suffered at least one rupture or RPR during follow-up. An increased risk was associated with pre-operative AAA size, rate of sac growth, and the number of previously detected complications. A prognostic model using only predicted sac growth had good discrimination at 2-years (C-index = 0.68), 3-years (C-index= 0.72) and 5-years (C-index= 0.75) post-operation and had excellent external validation (C-indices 0.76 to 0.79). After 5-years post-operation, growth rates above 1mm/year had a sensitivity of over 80% and specificity over 50% in identifying events occurring within 2 years. Secondary sac growth is an important predictor of rupture or RPR. A dynamic prognostic model has the potential to tailor surveillance by identifying a large proportion of patients who may require less intensive follow-up

Bubble Counter for Measurement of Air Bubbles During Thoracic Stent-Graft Deployment in a Flow Model.

BACKGROUND The aim of our study was to describe and validate the use of a bubble counter in an aortic flow model assessing the distribution of air bubbles in the supra-aortic vessel during thoracic stent-graft deployment. MATERIALS AND METHODS In an aortic flow model made by glass, identical tubular thoracic stent grafts (Zenith TX2 ProForm; Cook Medical, Bjaeverskov, Denmark) were deployed distal to the left subclavian artery. Four steps were defined during deployment: (1) introduction of the stent graft in the arch; (2) deployment of the stent graft; (3) proximal release of the stent graft; and (4) retrieval of the introduction system. On both sides, the common carotid and the vertebral artery were connected together, and the air bubbles were measured with one bubble counter probe per side. The number of air bubbles, as well as their size and distribution, is analyzed during these four steps for the left and right sides with a bubble counter. RESULTS Ten thoracic stent grafts were included in the study. The total number of air bubbles measured during all steps was significantly higher on the left side (1091 ± 255 versus 545 ± 288, P < 0.00001). During the third step, significantly higher numbers of bubbles were observed on the left side (P = 0.0000001) compared with the right side. The analysis of all bubbles by size revealed that a higher number of bubbles ranged 100-200 μm (P < 0.02) and 200-300 μm (P < 0.03) on the left side. Small bubbles were observed during all steps of deployment, whereas large bubbles appeared more commonly during the second and third steps. CONCLUSIONS A significant number of air bubbles are released during deployment of tubular thoracic stent grafts distally of the left subclavian artery in an aortic flow model. The distribution of air bubbles is bilateral with a higher number of air bubbles released on the left side

Use of a Steerable Sheath for Retrograde Access to Antegrade Branches in Branched Stent-Graft Repair of Complex Aortic Aneurysms.

PURPOSE To describe how to use a steerable sheath from a femoral access to catheterize antegrade branches in a branched aortic stent-graft. TECHNIQUE Following femoral cutdown, a stent-graft with antegrade branches destined for renovisceral target vessels was deployed in the desired position. A steerable sheath with a tip that rotates up to 180° was introduced from the common femoral artery and navigated to the antegrade branches for consecutive catheterization of the target vessels and deployment of one or more bridging stents per branch. The technique is demonstrated in 4 patients who underwent successful complex abdominal and thoracoabdominal branched endovascular repairs with 1, 2, and 4 antegrade branches. CONCLUSION Retrograde access for complex aortic endografts with antegrade branches using a steerable sheath appears feasible and effective and may serve as an alternative to upper extremity access