Abstract TP370: BRACE-WEB: A Brazilian Carotid Evolving Web Registry

Introduction: Carotid-web (Web-Ca) persists as an underrecognized cause of stroke, despite its rising presence in publications and scientific discussions. The lack of prospective studies results in a poor understanding of its recurrence rate, treatment strategies, and prevention. Even fewer data in the literature come from multiethnic populations. There is also a knowledge gap to be filled regarding its demographic characteristics, physiopathology, age of onset, and embolic triggers. We present an evolving prospective Brazilian cohort to describe the epidemiology, treatment outcomes, and long-term prognosis of patients diagnosed with Web-Ca. Methods: The study comprises two phases. The first retrospective phase included patients admitted to two comprehensive Stroke Centers in Brazil. A systematic evaluation involved an in-depth review of centers' neuroimaging (CTA/MRA/ Angiography) from 2017 to 2024. Two experienced stroke neurologists confirmed the diagnosis. Data on demographics, risk factors, treatment, and patient outcomes were gathered using a standardized questionnaire. The second prospective phase aims to include multiple centers from different regions of the country to achieve maximum representation possible. The sample is collected on an opportunistic, demand-driven basis in most of the centers; however, systematic investigation of key cases with advanced vascular imaging, such as CTA, is performed in the initial center for key suspected cases. The coordinator center systematically evaluates outpatient consultations. To reinforce methodology and avoid imaging biases, the Amsterdam University Medical Centers’ Team will anonymously validate image findings to perform final inclusion. Results: Sixty-eight cases were identified (55,2% female), median age 50 (IQR 40-59). Most patients were identified after ischemic stroke, with an initial NIHSS median of 11,29 (IQR 4-16). Twenty-nine patients (44,6%) received endarterectomy or angioplasty, and 46 (68,7%) were symptomatic. Web-Ca was the primary cause of stroke in sixteen (23,5%) cases and was identified in eleven hemorrhagic events. Conclusions: This ongoing cohort provides valuable insights into epidemiology, treatment outcomes, and long-term prognosis of patients with Web-ca in a multiethnic population, albeit it continuously generates new evidence. It underscores the importance of recognizing Web-Ca in the differential diagnosis of ischemic stroke etiology and flare-up the need for further research.