Preliminary observational studies have associated metformin prescription for diabetes treatment with reduced abdominal aortic aneurysm (AAA) growth progression. This proof of concept randomised controlled trial aimed to evaluate the efficacy of metformin intake on AAA growth progression in patients without diabetes. This was a randomised, double blind, placebo controlled clinical trial of 2 g metformin vs. placebo in non-diabetic patients with AAA. Fifty eight patients with an infrarenal AAA with a maximum aortic diameter between 3.0 cm and 4.9 cm were included after a 14 day run in phase assessing drug tolerability. The recruitment target of 170 patients was not achieved due to the COVID-19 pandemic. The maximum aortic diameter and aneurysm volume were measured at baseline, after six and 12 months of treatment, and at 18 months follow up using computed tomography angiography. The prespecified primary outcome was maximum aortic diameter change between baseline and 12 month visit. Differences in maximum aortic diameter from baseline to six, 12, and 18 months between the metformin and placebo groups were -0.10 mm (95% confidence interval [CI] -0.62 - 0.43 mm; p = .71), 0.16 mm (95% CI -0.70 - 1.02 mm; p = .72), and 0.31 mm (95% CI -0.86 - 1.48 mm; p = .59), respectively. The corresponding differences in aortic volume were -0.19 cm³ (95% CI -2.52 - 2.14 cm³; p = .87), 1.65 cm³ (95% CI -2.45 - 5.76 cm³; p = .42), and 2.10 cm³ (95% CI -3.45 - 7.65 cm³; p = .45). Amongst 58 randomised patients who completed the 12 month treatment phase, medication adherence was 94.87%. No difference in AAA growth between the metformin and placebo groups was observed. Patients had excellent adherence and tolerability to metformin therapy. Considering the lack of power of the study, larger randomised controlled trials with longer follow up are required to detect smaller treatment effects.

Background: Monitoring of abdominal aortic aneurysms (AAAs) is currently based on serial measurements of maximum aortic diameter. Additional assessment of aneurysm volume has previously been proposed to possibly improve growth prediction and treatment decisions. To evaluate the use of supplementing volume measurements, the authors aimed to characterise the growth distribution of AAA volume and to compare the growth rates of the maximum diameter and volume at the patient level. Methods: Maximum diameter and volume were monitored every 6 months in 84 patients with small AAAs, with a total of 331 computed tomographic angiographies (with initial maximum diameters of 30–68 mm). A previously developed statistical growth model for AAAs was applied to assess the growth distribution of volume and to compare individual growth rates for volume and for maximum diameter. Results: The median (25–75% quantile) expansion in volume was 13.4 (6.5–24.7) % per year. Cube root transformed volume and maximum diameter showed a closely linear association with a within-subject correlation of 0.77. At the surgery threshold maximum diameter of 55 mm, the median (25–75% quantile) volume was 132 (103–167) ml. In 39% of subjects, growth rates for volume and maximum diameter were equivalent, in 33% growth was faster in volume and in 27% growth was faster in maximum diameter. Conclusion: At the population level, volume and maximum diameter show a substantial association such that the average volume is approximately proportional to the average maximum diameter raised to a power of three. At the individual level, however, in the majority of patient’s AAAs grow at different pace in different dimensions. Hence, closer monitoring of aneurysms with sub-critical diameter but suspicious morphology may benefit from complementing maximum diameter by volume or related measurements.

Complex endovascular aortic repair (coEVAR) of thoracoabdominal aortic aneurysms (TAAA) has greatly evolved in the past decades. Despite substantial improvements of postoperative care, spinal cord injury (SCI) remains the most devastating complication of coEVAR being associated with impaired patient outcome and having an impact on long-term survival. The rising number of challenges of coEVAR, essentially associated with an extensive coverage of critical blood vessels supplying the spinal cord, resulted in the implementation of dedicated SCI prevention protocols. In addition to maintenance of adequate spinal cord perfusion pressure (SCPP), early detection of SCI plays an integral role in intra- and postoperative patient care. However, this is challenging due to difficulties with clinical neurological examinations during patient sedation in the postoperative setting. There is a rising amount of evidence, suggesting that subclinical forms of SCI might be accompanied by an elevation of biochemical markers, specific to neuronal tissue damage. Addressing this hypothesis, several studies have attempted to assess the potential of selected biomarkers with regard to early SCI diagnosis. In this review, we discuss biomarkers measured in patients undergoing coEVAR. Once validated in future prospective clinical studies, biomarkers of neuronal tissue damage may potentially add to the armamentarium of modalities for early SCI diagnosis and risk stratification.

To assess the early experience with modified version of simplified bare-wire target vessel (SMART) technique, implying delivery of bridging stent graft (BSG) without historically established sheath support, and to compare its outcome to standard endovascular aortic repair procedures with fenestrated/branched devices (F/B-EVAR). A retrospective analysis of 102 consecutive patients treated with F/B-EVAR from January 2020 to December 2022 was undertaken. Study population was divided into three groups - sheath group (SG), SMART and non-sheath (NSG). Primary endpoints were radiation exposure (dose-area product, DAP), fluoroscopy time (FT), dose of contrast agent (CA), operation time and incidence of intraoperative target vessel (TV) complications and additional procedures. Freedom from secondary TV related reinterventions at 3 follow-up phases were defined as secondary endpoints. A total of 183 TVs (38.8% visceral arteries [VA]; 56.3% renal arteries [RA]) in SG, 36 TVs (44.4% VA, 55.6% RA) in SMART group, and 168 TVs (47.6% VA; 50% RA) in NSG were accessed. The mean number of fenestrations and BSGs was equally distributed in all three groups. SMART group only included cases treated with fenestrated devices. DAP was significantly lower in SMART (median, 203 Gy x cm²; interquartile range [IQR], 179-365) and NSG (median, 340 Gy x cm²; IQR, 220-651) groups vs. SG (median, 464; IQR, 267-871) P = .007. Operation time was also significantly lower in NSG (median, 265 minutes; IQR, 221-337) and SMART (median, 292; IQR, 234-351) groups vs. SG (median, 326 minutes; IQR, 277-375), P = .004, respectively. Intraoperative TV related complications were most frequently observed in SG (9/183 TVs), P = .008. This study reports outcomes of three currently available TV stenting approaches. Previously reported SMART technique, and its modified version (NSG) proved to be a safe alternative to historically established TV stenting technique with sheath support (SG).

Endovascular aortic repair (EVAR) with fenestrated (F-EVAR) or branched (B-EVAR) endografts represents an indispensable tool of modern patient care in vascular surgery. The purpose of this retrospective study was to evaluate the center's initial experience of F/B-EVAR procedures performed under biplane angiography guidance compared with a historical control group. From January 2020 to March 2022, 80 consecutive patients underwent F/B-EVAR under general anesthesia at a single institution. As from January 2021, the deployment of complex stent grafts was performed using an alternative intraoperative imaging modality-a biplane fluoroscopy and angiography. The cohort was divided into monoplane (MPA) and biplane (BPA) groups according to the imaging modality applied. The end points were operation time, fluoroscopy time, radiation exposure, dose of contrast agent, and technical success. The MPA group included 59 patients (78% male; median age; 74 years; interquartile range [IQR], 66-78 years) and the BPA group 21 patients (85.7% males; median age, 75 years; IQR, 69-79 years). Operation time (median, 320 minutes; IQR, 266-376 minutes) versus (median, 275 minutes; IQR, 216-333 minutes) was significantly lower in the BPA group (P = .006). The median fluoroscopy time (median, 82 minutes; IQR, 57-110 minutes vs median, 68 minutes; IQR, 54-92 minutes), contrast agent volume applied (median, 220 mL; IQR, 179-250 mL vs median, 200 mL; IQR, 170-250 mL), and radiation dose (dose-area product, median, 413 Gy × cm²; IQR, 249-736 Gy × cm²; vs median, 542 Gy × cm²; IQR, 196-789 Gy × cm²) were similar in both groups. Technical success of 96.6% (57/59 cases) versus 100% (21/21 cases) could be achieved in MPA and BPA group, respectively. F/B-EVAR procedures performed under BPA guidance were associated with a significant decrease in operation time.

Background: Abdominal aortic aneurysm (AAA) is a multifactorial vascular disease associated with high morbidity and mortality. Currently, surgical intervention is the only treatment option, and there is no drug therapy available for AAA. Hence, surveillance of AAA until indication for surgery may impact patient quality of life (QoL). There is a paucity of high-quality observational data on health status and QoL, particularly among AAA patients participating in randomized controlled trials. The objective of this study was to compare the QoL scores of AAA patients on surveillance to those of AAA patients enrolled in the MetAAA trial. Material and methods: Overall, 54 MetAAA trial patients and 23 AAA patients under regular surveillance for small AAA (part of a longitudinal monitoring study) were asked to complete three established and validated (in total 561 longitudinally collected) QoL questionnaires: the 36-Item Short Form Health Survey (SF-36), the Aneurysm Symptom Rating Questionnaire (ASRQ), and the Aneurysm-Dependent Quality of Life questionnaire (ADQoL). Results: A superior health status and QoL was found in AAA patients participating in the MetAAA trial compared to AAA patients under regular surveillance. In detail, MetAAA trial patients showed superior general health perception (P=0.012), higher energy level (P=0.036) as well as enhanced emotional well-being (P=0.044) and fewer limitations due to general malaise (P=0.021), which was subsequently reflected in an overall superior current QoL score (P=0.039) compared to AAA patients under regular surveillance. Conclusion: AAA patients enrolled in the MetAAA trial showed superior health status and QoL compared to AAA patients under regular surveillance.