Introduction: Cerebral embolization is a major complication of carotid artery stenting (CAS). Remote ischemic preconditioning (RIPC) have been shown to reduce distal embolization in coronary stenting, but it is unclear whether RIPC can reduce embolization after CAS.
Objective: To evaluate the effect of RIPC on cerebral embolization after CAS
Hypothesis: We assessed the hypothesis that RIPC can reduce new vascular brain injury early after CAS.
Methods: 189 symptomatic carotid artery stenosis patients treated with CAS, were allocated randomly to RIPC group, control group, and sham RIPC group. All patients received standard background medical therapy. Patients in the RIPC and sham RIPC group underwent RIPC and sham RIPC twice daily respectively. The primary outcome was incidence of new brain parenchymal lesions on MRI at 48hr after CAS. The secondary outcomes were lesion size and occurrence of clinical events within 6 months after CAS. One-way ANOVA, Chi-Square test and Wilcoxon signed-rank test were used accordingly.
Results: 162 patients, who completely finished CAS and MRI, were included in the primary analysis. Incidence of new lesions on post-treatment MRI was 19.23% in the RIPC group, 46.43% in the control group (RR, 0.41; 95% CI 0.22-0.77; p=0.003) and 42.59% in the sham RIPC group (RR, 0.45; 95% CI 0.24-0.85; p=0.009). Median volumes of new lesions and median total lesion volume were both smaller in RIPC group than other 2 groups (p<0.01 each). However, no statistical difference was observed between the groups regarding clinical events.
Conclusions: RIPC was associated with a significant reduction in the occurrence of new brain parenchymal lesions within 2 days of CAS. These results need to be replicated and future larger studies should be sufficiently powered to examine the effect of RIPC on clinical events after CAS.