Carotid sinus reactions during carotid artery stenting: Predictors, incidence, and influence on clinical outcome

Abstract Carotid sinus reactions (CSR), defined as asystole ≥ 3 sec and hypotension (systolic blood pressure ≤ 90 mm Hg), are frequent events during carotid artery stenting (CAS). Factors predisposing a patient to CSR as well as the impact of CSR on periprocedural complications have not yet been investigated in a prospective manner. The relationship between various clinical, morphologic, and procedural variables and the occurrence of CSR was examined among 105 consecutive patients undergoing successful CAS. After predilatation with a compliant balloon, tubular‐slotted stents were used in all patients. No CSR occurred in 63 (60%) patients, whereas CSR developed in 42 (40%) patients. The most common type of CSR was asystole in combination with short‐term hypotension without clinical symptoms. The most important predictor of CSR was bifurcation location of carotid stenosis (bifurcation > ostial > isolated internal carotid artery; P < 0.001). The other independent predictors were presence of contralateral stenosis ( P < 0.02), length of stenosis ( P < 0.03), and balloon‐to‐artery ratio ( P < 0.02). Occurrence of CSR was unrelated to periprocedural cerebral or cardiovascular complications (7.1% vs. 9.5%; NS). We conclude that CSR occurs frequently (40%) during CAS. Bifurcation location of stenosis is the most important predictor of CSR. CSR does not increase the risk of periprocedural complications. Cathet Cardiovasc Intervent 2003;58:516–523. © 2003 Wiley‐Liss, Inc.