Innovative application of pressure gradient measurement in internal carotid stenosis in patients undergoing carotid artery stenting (NOTICE-CAS): study protocol for a randomized, assessor-blinded, parallel-group clinical trial

Atherosclerotic stenosis of the internal carotid artery (ICA-S) is among the significant causes of ischemic stroke. Current noninvasive imaging techniques often lack the precision to accurately determine hemodynamic significance. Although carotid artery stenting (CAS) is beneficial in symptomatic patients, its role in asymptomatic cases remains unclear. The NOTICE-CAS study aims to evaluate the association between invasive pressure gradient measurement (Pd/Pa) during CAS and improvement in cerebral perfusion, and to develop a computed tomography-based Pd/Pa index to optimize qualification for revascularization. This study is a randomized (1:1), assessor-blinded, parallel-group clinical trial comparing two procedural strategies: standard CAS (Group 1, control) versus CAS supplemented with intravascular pressure gradient measurement (Group 2, intervention). The primary outcome is the association between Pd/Pa measured during CAS and the change in cerebral blood flow (ΔCBF) at three months postprocedure. Key secondary outcomes include associations of Pd/Pa with additional perfusion MRI parameters (ΔMTT, ΔrCBV, ΔTTP), cognitive performance (ΔMoCA), neurological status (ΔNIHSS), and otolaryngological outcomes. Safety outcomes (MACCE within 30 days) will be compared between procedural strategies in an exploratory non-inferiority analysis. A total of 200 participants will be enrolled. The NOTICE-CAS trial was designed to explore whether invasive pressure gradient measurement during CAS can improve patient selection for carotid revascularization. The results may help reduce the number of procedures performed in patients unlikely to benefit. ClinicalTrials.gov, NCT06123767 . Registered on March 7, 2024.