Vassiliki Kigka ^1,2 Alessandro Carrozzi ^3,4 Laura Ludovica Gramegna ^5,6* Panagiotis Siogkas ^1,2 Vassiliki Potsika ^1,2 Vassilis Tsakanikas ^1,2 Michael Kallmayer ⁷ Victor Obach ⁸ Vincente Rimbau ⁸ Giovanni Spinella ^10,9 Giovanni Pratesi ^10,9 Luigi Cirillo ^11,3 David Neil Manners ^12,3 Rodolfo Pini ^13,4 Gianluca Faggioli ^13,4 Ger Jan de Borst ¹⁴ George Galyfos ¹⁵ Fragiska Sigala ¹⁵ Perica Mutavdzic ^16,17 Marija Jovanovic ^16,17 Igor Koncar ^16,17 Dimitrios Fotiadis ^1,2

• ¹ Unit of Medical Technology and Intelligent Information Systems, Department of Materials Science and Engineering, School of Engineering, University of Ioannina, Ioannina, Greece
• ² Institute of Molecular Biology and Biotechnology, Biomedical Research Institute (BRI), Ioannina, Greece
• ³ Functional and Molecular Neuroimaging Unit, IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Emilia-Romagna, Italy
• ⁴ Department of Medical and Surgical Sciences, University of Bologna, Bologna, Emilia-Romagna, Italy
• ⁵ Vall d'Hebron Research Institute (VHIR), Barcelona, Catalonia, Spain
• ⁶ Hospital del Mar, Parc de Salut Mar, Barcelona, Catalonia, Spain
• ⁷ Department of Vascular and Endovascular Surgery, University Hospital rechts der Isar, Technical University of Munich, Munich, Bavaria, Germany
• ⁸ Clinic Barcelona Research Foundation, Barcelona, Balearic Islands, Spain
• ⁹ Unit of Vascular and Endovascular Surgery Clinic, Department of Cardio, Thoraco, Vascular, San Martino Hospital (IRCCS), Genoa, Italy
• ¹⁰ Department of Integrated Surgical and Diagnostic Sciences, School of Medical and Pharmaceutical Sciences, University of Genoa, Genova, Italy
• ¹¹ Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Emilia-Romagna, Italy
• ¹² Department for Life Quality Studies, University of Bologna, Bologna, Emilia-Romagna, Italy
• ¹³ Department of Vascular Surgery, IRCCS University Hospital of Bologna Sant Orsola Polyclinic, Bologna, Emilia-Romagna, Italy
• ¹⁴ Department of Vascular Surgery, University Medical Center Utrecht, Utrecht, Netherlands, Netherlands
• ¹⁵ Department of Vascular Surgery, National and Kapodistrian University of Athens Medical School, Athens, Greece
• ¹⁶ Faculty of Medicine, University of Belgrade, Belgrade, Serbia
• ¹⁷ Clinic for Vascular and Endovascular Surgery, Clinical Center of Serbia, University of Belgrade, Belgrade, Serbia

INTRODUCTION The relationship between carotid artery stenosis (CAS) and ipsilateral silent brain ischemia (SBI) remains unclear, with uncertain therapeutic implications. The presented study, part of the TAXINOMISIS project (nr. 755320), focused on investigating SBIs in patients with asymptomatic CAS, correlating them with clinical and carotid ultrasonographic data, including also computational fluid dynamics (CFD) analyses. METHODS The TAXINOMISIS clinical trial study (nr. NCT03495830) involved six clinical centers of vascular surgery in Europe, enrolling patients with asymptomatic and symptomatic CAS ranging from 50% to 99%. Patients underwent carotid ultrasound and magnetic resonance imaging (MRI), including brain diffusion-weighted, T2-weighted/FLAIR, and T1-weighted sequences. Brain MRI scans were analyzed for the presence of SBI according to current definitions. Ultrasound assessments included Doppler and CFD analysis. Only asymptomatic patients were included in this substudy. RESULTS Among 195 asymptomatic patients, the mean stenosis (NASCET) was 64.1%. Thirty-three (16.9%) had at least one SBI detected on brain MRI, in detail: 19/33 (57.6%) had cortical infarcts, 4/33 (12.1%) ipsilateral lacunar infarcts, 6/33 (18.2%) subcortical infarcts, 1/33 (3.0%) both a cortical and a lacunar infarct, and 3/33 (9.1%) both a cortical and a subcortical infarct. Patients with SBIs had significantly higher risk factors including body mass index (28.52±9.38 vs 26.39±3.35, p=0.02), diastolic blood pressure (80.87±15.73 mmHg vs 80.06±8.49 mmHg, p=0.02), creatinine levels (93.66±34.61 µmol/L vs 84.69±23.67 µmol/L, p=0.02), and blood triglycerides (1.8± 1.06 mmol/L vs 1.48±0.78 mmol/L, p=0.03), along with a history of cardiovascular interventions (29.6% vs 13.8%, p=0.04), higher usage of third/fourth-line antihypertensive (50%vs16%, p=0.03) and anticoagulant medications (60% vs 16%, p=0.01), and higher number of contralateral cerebral infarcts (35.5% vs 13.4%, p<0.01 ). Moreover, carotid ultrasound revealed higher Saint Mary's Ratios (15.33± 12.45 vs 12.96±7.99, p=0.02), and CFD analysis demonstrated larger areas of low wall shear stress (0.0004±0.0004 m2 vs 0.0002±0.0002 m2, p<0.01). CONCLUSIONS The TAXINOMISIS clinical trial provides important insights into the prevalence and risk factors associated with SBIs in patients with moderate asymptomatic carotid stenosis. The associations between SBIs and certain findings further support the notion that specific hemodynamic and arterial wall characteristics may contribute to the development of silent brain infarcts.