Usefulness of intravascular pressure ratio measurement for cerebral hemodynamics in carotid artery stenting patients

The role of intravascular pressure ratio across carotid artery stenosis in assessing cerebral hemodynamics remains unclear. This study evaluated the utility of pressure-wire-based carotid pressure ratio (CPR) measurement during carotid artery stenting (CAS) in patients with internal carotid artery (ICA) stenosis. We prospectively enrolled 25 patients undergoing CAS for unilateral ICA stenosis. CPR was defined as the ratio of mean arterial pressure distal to proximal to the stenosis, measured before and after CAS using a pressure wire. We analyzed the correlation of CPR with cerebral vascular reserve (CVR), cerebral blood flow asymmetry index (CBF-AI), and stenosis-related parameters. Receiver operating characteristic (ROC) analysis identified optimal CPR thresholds. CPR significantly correlated with CVR (R² = 0.38), CBF-AI, and stenosis severity. A CPR ≤ 0.80 accurately predicted impaired CVR (< 10%) with 100% sensitivity and 89% specificity. The CPR reached 1.0 when the minimal luminal diameter was ≥ 1.96 mm, suggesting resolution of the pressure gradient. No complications were observed with intraoperative CPR measurement. CPR measurement using a pressure wire is safe, minimally invasive, and reflects cerebral hemodynamic status. The CPR may complement imaging-based evaluation and support intra- and post-operative management in ICA stenosis. Further validation in larger multicenter cohorts is warranted.