Dynamic cerebral autoregulation and exercise-induced neurovascular coupling as potential markers of cerebral hyperperfusion after carotid stenting

This study aimed to prospectively evaluate whether impaired dynamic cerebral autoregulation (dCA) and exercise-induced neurovascular coupling (NVC) parameters in carotid stenosis predict cerebral hyperperfusion (CH) after carotid artery stenting (CAS). This study was conducted based on prospectively collected data from a single-center observational registry. Between October 2023 and September 2024, the registry enrolled 237 patients scheduled to undergo CAS, all with carotid artery stenosis (≥ 70% for asymptomatic or ≥ 50% for symptomatic stenosis). To assess NVC, transcranial Doppler (TCD) was performed within 24 h prior to CAS. NVC was evaluated by measuring the increase in cerebral blood velocity (CBv) in the middle cerebral artery (MCA) during stimulation. Ultimately, 93 patients proceeded to stenting and were included in the present analysis. Among 93 patients undergoing CAS, 16.1% ( n = 15) developed CH. These patients exhibited significantly lower phase values in very low frequency (VLF) compared to non-CH patients during exercise (23.12° vs. 41.82°, p < 0.05). NVC was compromised in CH patients, demonstrated by reduced exercise-induced flow response (EIFR) (5.6% vs. 8.6%, p = 0.041) and Δcerebrovascular conductance index (ΔCVCi) ( p = 0.015). The hemodynamic and regulatory model integrating phase at VLF, ΔCVCi, and EIFR showed a higher AUC compared with the clinical model, though the difference did not reach statistical significance ( p = 0.20). This study suggests that dCA and NVC parameters during exercise stimulation may serve as potential predictors of CH after CAS, supporting further investigation of cerebrovascular autoregulation assessment in preoperative evaluation for carotid revascularization.