Transcranial Doppler for internal carotid artery stenting: rationale and design of a randomized controlled trial.

BACKGROUND: Carotid artery stenting (CAS) is an effective revascularization procedure for internal carotid artery stenosis, but it is associated with a high incidence of perioperative cerebral embolism, with asymptomatic and symptomatic embolic events occurring in up to 40% of patients. Transcranial Doppler (TCD) has been shown to enhance fibrinolysis through sonothrombolysis and may reduce embolic burden during carotid interventions. AIMS: To evaluate whether intraoperative and post-procedural TCD monitoring can reduce the number of new diffusion-weighted imaging (DWI) lesions after CAS in patients with severe internal carotid artery stenosis. SAMPLE SIZE ESTIMATES: A total of 232 patients are required to detect a 50% reduction in the median number of new DWI lesions (from 2.0 to 1.0) with 80% power and a two-sided α of 0.05, accounting for a 5% dropout rate. DESIGN: TCD-ICAS is a prospective, randomized, single-center, blinded endpoint trial. Patients scheduled for CAS are randomized 1:1 to receive either TCD treatment (1.6 MHz, 0.274 MPa) from femoral artery puncture until 30-60 min after procedure completion plus standard care, or standard care alone. OUTCOMES: The primary efficacy endpoint is the number of new DWI lesions at 24 h post-randomization. The primary safety endpoint is intracranial hemorrhage within 24 h. CONCLUSION: The TCD-ICAS trial will assess the efficacy and safety of TCD as an adjuvant therapy to reduce cerebral embolic events in patients undergoing CAS. CLINICAL TRIAL REGISTRATION: Identifier (NCT07462546).