Abstract
Objective: The outcome of using a closed-cell type self-expanding stent (closed-cell stent) for tortuous internal carotid artery (ICA) stenosis is unknown. This study aimed to assess the association between the tortuosity of the carotid artery and microembolization identified on diffusion-weighted imaging during carotid artery stenting (CAS) using a closed-cell stent.
Method: We retrospectively analyzed data from a registry of 93 consecutive patients who underwent CAS using a closed-cell stent at our institute. We used the following as tortuosity indexes: the angle between the common carotid artery and the ICA (Angle A), the angle at the first bend in the ICA (Angle B), and the sum of Angle A and Angle B (Angle A + B). We assessed the relationship between the tortuosity index and microembolizations as well as the cut-off values of the tortuosity indexes by receiver operating characteristic (ROC) curve analysis and odds ratio (OR) of microembolization.
Result: Microembolizations were detected in 18 of 93 (19.4%) patients and significantly associated with Angle B (65.6 ± 24.2°, 47.9 ± 25.3°; p = 0.009) and Angle A + B (99.0 ± 39.0°, 76.2 ± 33.6°; p = 0.028) but not Angle A (33.4 ± 17.6°, 28.2 ± 13.7°; p = 0.174). ROC curve analysis showed that the best cut-off values for Angle B and Angle A + B were 40.5° and 60.5°, respectively. The OR of microembolization in patients with Angle B >40.5° and Angle A + B >60.5° was 4.146 and 9.020, respectively.
Conclusion: In CAS using closed-cell stents, Angle B and Angle A + B are significantly associated with the incidence of microembolization.
