Objectives: The choice of vascular access continues to be a critical component in the management of hemodialysis patients. Despite the international consensus favoring arteriovenous (AV) fistulas, the use of central venous catheters (CVCs) remains prevalent, with substantial variations across countries and even among dialysis centers within the same region. This study examines the prevalence of CVC use among chronic hemodialysis (CHD) patients in Vienna, Austria, and explores inter-center differences. Methods: A cross-sectional analysis was conducted on patients receiving CVC-based CHD in Vienna as of March 2023. Patient demographics, comorbidities and their hemodialysis history were collected. Additionally, a subset of the population underwent vascular access (VA) mapping to assess eligibility for AV fistula (AVF) or AV graft (AVG) creation. Results: A total of 335 patients received CVC-based hemodialysis, equaling a CVC proportion of 42.5%. 191 (57.0%) patients on CVC-based CHD gave their consent to record their clinical data and vascular access history. Of the 191 included patients, 61 gave their consent to receive VA mapping. Of the 61 patients who received VA mapping, 60 (98.4%) were eligible for an upper extremity AVF or AVG. There was no significant difference regarding patient demographics, dialysis vintage, history of previous AVF or AVG or Charlson Comorbidity Index between the mapping and non-mapping group. The odds ratio of having a CVC in the absence of in-house vascular surgery was 3.41 (95% CI: 2.31–5.02, p-value < 0.001) compared to patients with in-house vascular surgery. Conclusions: The majority of patients that consented to ultrasound VA mapping fulfilled vascular requirements for AVF or AVG creation. Our study highlights the potential to decrease the prevalence of CVC-based CHD in Vienna that could translate to a reduction in CVC-associated complications.

Summary Background Intimate knowledge of the materials used in endovascular aortic interventions is essential for trainees and supporting staff taking part in an endovascular intervention. Training courses can help to familiarize trainees with the equipment. However, the pandemic has changed the landscape of hands-on training courses significantly. Therefore, we developed a training course including an educational recording of the procedure to transfer knowledge about the materials used during endovascular interventions and radiation exposure reduction. Methods We produced a video depicting cannulation of the left renal artery in a silicon cast of an aorta and its major side branches under C‑arm fluoroscopy. A presentation using the video was given to the trainees. The trainees were randomized into a control and an intervention group. Their performance was filmed and rated on a standardized five-point scale in the style of the OSATS global rating scale. The intervention group was remeasured after additional training time. Results In total, 23 trainees participated in the training and agreed to have their performance recorded. The control and intervention groups showed no difference in the assessed performance metrics during their initial attempt. However, after receiving additional training, the intervention group significantly improved in all evaluated metrics. Conclusion Our data add to the growing evidence that simulator-based training can help to increase trainees’ understanding and performance of relevant skills. A standardized and evidence-based validation process for simulators could improve their acceptance in the medical field.

Background/Objectives: Hemodialysis (HD) is a life-sustaining treatment for an increasing number of patients around the globe. The options for vascular access (VA) in HD are arteriovenous fistulas (AVFs), arteriovenous grafts (AVGs), and central venous catheters (CVCs). AVFs are historically associated with better long-term outcomes. Recently, international guidelines have shifted to a more individualized approach driven by evidence that patient-specific factors influence the success of AVF creation. The initial “Vienna ACTS NOW” study revealed significant inter-center variability in CVC prevalence in Vienna. This two-year follow-up aimed to document the continuing variability in CVC-based HD management and to monitor the clinical outcomes and cost associated with an attempted conversion to AVF/G. Methods: This multi-center cohort study collected data (March 2023 to March 2025) on 153 CVC-based HD patients from six Viennese institutions. Primary endpoints included VA-related events and patency; the secondary endpoint was overall mortality. Costs were calculated using the Austrian Catalogue for Medical Services (MEL). Results: Overall, 28 (18.3%) out of 153 patients underwent AVF/G surgery, and 20 (71.4%) achieved successful cannulation. A total of 12 surgical and 14 endovascular interventions were performed to either support VA maturation or maintain patency. The median hospital admission was 3 days for VA creation and 4 days for later interventions. VA creation in patients that did not require later interventions cost 3130.44 € per patient, and it cost 11,893.02 € in patients that did. The proportion of AVF/G creation attempts varied from 0% to 40.9% between centers. Patients who underwent VA-creating surgery had a better rate of survival after two years compared to patients who did not undergo VA-creating surgery. (86.2% vs. 63.3% p < 0.02). Overall, 6.3% of deaths were related to VA management. Conclusions: Patient-specific characteristics and the capability of the healthcare system to timely detect and treat CKD might influence the outcome of patients. The proportion of CVC- and AVF/G-based HD might therefore be associated with the level of access patients have to the healthcare system and the efficiency of the care network. Our own data point towards a difference in CVC use between different centers in Vienna, not solely driven by patient characteristics, but by locally available resources and differences in policies.

Fenestrated endovascular aneurysm repair (FEVAR) enables treatment of complex aortic aneurysms involving visceral branches but is limited by patient-specific anatomical variability. Off-the-shelf (OTS) devices could reduce manufacturing delay; however, their feasibility depends on anatomic compatibility across populations. A large multicenter dataset was analysed to evaluate the anatomic feasibility of standardized OTS fenestrated stent-graft configurations for juxtarenal and pararenal abdominal aortic aneurysms (AAAs) in this retrospective anatomic study. Computed tomography angiography (CTA) data from a sample of 8,238 patients evaluated for FEVAR between January 2018 and December 2023 were analysed. Measurements of the celiac axis (CA), superior mesenteric artery (SMA), left renal artery (LRA), and right renal artery (RRA) included ostial distance and branching angle relative to the CA. A greedy set-cover algorithm identified the smallest number of OTS configurations achieving fenestration target vessel alignment (FTVA). Cumulative coverage and clustering by aortic diameter were assessed. Analyses were exploratory and descriptive. Anatomic data were available in 57.1% of cases for the SMA, 96.1% for the LRA, and 96.8% for the RRA. The CA served as the reference point for all analyses. Eight configurations covered 81.9% of SMA, 49.7% of LRA, and 52.9% of RRA anatomies. SMA coverage exceeded 90% with 16 designs, while 20 configurations were required for each renal artery to reach 80% coverage. No clustering of vessel origin by aortic diameter (median 28 mm; interquartile range 26-30.5 mm) was observed. Below 70% coverage for three-vessel and <25% for four-vessel combinations was achieved with the top 100 configurations. A standardized dual-fenestrated OTS platform incorporating the CA and SMA appears anatomically feasible for most patients, whereas renal artery variability limits multi-vessel standardization. Dual-fenestrated devices with renal branches could also circumvent these constraints fully.