Correlation between Preoperative Blood Pressure Variability and Carotid Sinus Reaction after Internal Carotid Artery Stenting

Abstract

AIM: To investigate the relationship between blood pressure variability (BPV) 24 hours before internal carotid artery stenting and post-procedural carotid sinus reaction (CSR), with an emphasis on identifying BPV indexes that predict the implementation of carotid artery stenting (CAS) and the subtype of CSR.

METHODS: A total of 105 patients who completed 24-hour ambulatory blood pressure monitoring and underwent CAS from August 2019 to February 2024 in the First Affiliated Hospital of Bengbu Medical College were included in this study. Patients were divided into CSR and non-CSR groups. The CSR group was further divided into three subgroups according to the type of CSR that occurred: namely hypotensive, bradycardic, and mixed types. Prior to stent placement, changes in ambulatory blood pressure were monitored using a fully automated non-invasive portable blood pressure monitor for 24 hours before the procedure, and the individual metrics in BPV were compared.

RESULTS: CSR occurred in 69 patients (65.71%) and the remaining 36 patients did not experience CSR (34.29%). Among the patients with CSR, 46 (66.67%) experienced hypotensive CSR, 9 (13.04%) had bradycardic CSR, and 14 (20.29%) mixed-type CSR. The age, history of hypertension, coronary artery disease, and history of smoking were significantly higher in the CSR group than in the non-CSR group (p = 0.007, p = 0.002, p = 0.046, p = 0.007, respectively). Age, hypertension, and history of smoking were the risk factors for CSR. A statistically significant difference in triglyceride levels was found between the three subgroups of CSR (p < 0.05); however, triglycerides had no significant effect on the type of CSR subgroups (all p > 0.05). A series of preoperative BPV indexes, like the maximum systolic blood pressure (SBP), SBP's max-min difference, mean, standard deviation (SD), coefficient of variation (CV), and degree of variability (SV) of the 24-hour SBP, were significantly correlated with the occurrence of CSR (p < 0.05). Further analysis revealed that SBP's max-min difference, SD, CV, and SV of 24-hour SBP were independent predictors of CSR. The bradycardic CSR was significantly correlated with the maximum diastolic blood pressure (DBP), minimum DBP, and 24-hour mean DBP, when compared to the hypotensive CSR (p < 0.05). The mixed-type CSR was significantly correlated with the maximum DBP and minimum DBP, when compared to the bradycardic CSR (p < 0.05).

CONCLUSIONS: The indexes of BPV 24 hours before internal carotid artery stenting correlate with the occurrence and types of CSR. Therefore, BPV can be used as a predictor of the occurrence and specific type of CSR after internal carotid artery stenting.