Predictors of the multiwire technique use in carotid artery stenting

The multiwire technique (MWT) in carotid artery stenting (CAS), characterized by the use of more than one guidewire to support guiding catheter in patients with hostile neck anatomy, increases procedural time, enhancing the risk of periprocedural stroke. The aim of the present study was to identify which factors are predictors of the MWT use in CAS, in order to stratify patients with longer procedure at potential higher risk of periprocedural stroke.

The study retrospectively included patients who underwent CAS for stenotic plaque between January 2015 and December 2019. Exclusion criteria was incomplete clinical data. For each patients were registered clinical data, main aortic arch and supra-aortic vessel anatomical features, carotid plaque characteristics, and procedural details. The sample was divided in two group on the basis of the number of guides used during the stenting procedure: one guide (standard technique, ST) or more than one guidewire (MWT) to support the guiding catheter. Differences between groups were tested by Chi-square text or Fisher's exact test and Mann-Whitney U test. Logistic regression analysis was used to identify predictors for the use of the MWT. The area under the ROC (AUC) curve was used to assess performance of the model to predict the use of the multiwire technique.

The final sample included 146 of the 204 (71%) patients who underwent CAS during the study period. The median age of the patients was 79 years (IQR 71-83 years) with 47/146 (32%) females. CAS was performed with MWT in 17/146 (12%) of the cases. MWT was used more likely in patients with aortic arch type II or III as compared to ST (71% vs 37%, P = 0.02) while plaques with heavy concentric calcifications were more frequent in ST as compared to MWT (38% vs 12%, P = 0.03). At multivariable analysis aortic arch type II or III (OR 5.08, 95% CI 1.48-17.93, P < 0.01), plaque stenosis > 79% (OR 4.13, 95% CI 1.03-16.61, P = 0.04), and plaque heavy concentric calcifications (OR 0.19, 95% CI 0.04-0.94, P = 0.04) were independent predictors of MWT use. The model showed an AUC of 0.827 (95% CI 0.756-0.884) for the prediction of the MWT use during CAS.

Aortic arch type II or III, carotid plaque with stenosis higher than 79% of the lumen or without heavy concentric calcifications were predictors for the use of the MWT during CAS. These features should be considered during planning of CAS as hallmark of vascular stiffness and therefore of higher procedure complexity.