A diffusion-weighted magnetic resonance imaging-based study of transcervical carotid stenting with flow reversal versus transfemoral filter protection

Abstract

Background: Transfemoral carotid artery stenting (CAS) has been associated with a high incidence of embolic phenomena and silent brain infarction. The goal of this study was to compare the incidence of new ischemic cerebral lesions on diffusion-perfusion magnetic resonance imaging (MRI) sequences after transcervical CAS performed with carotid flow reversal vs stenting via transfemoral approach with distal filter protection.

Methods: During a 26-month period, 64 consecutive patients diagnosed with significant carotid stenosis by ultrasound imaging were assigned to transcervical CAS with carotid flow reversal or a transfemoral approach with a distal filter. The Rankin stroke scale was administered by an independent neurologist, and diffusion-weighted MRI (DW-MRI) studies were performed ≤24 hours before and ≤24 to 48 hours after the procedure. DW-MRI studies were compared by two neuroradiologists not involved in the study and blinded for time, clinical status, and treatment option. Hyperintense DW-MRI signals found after the procedure were interpreted as postoperative ischemic infarcts. All patients were assessed at 1, 6, and 12 months after the intervention.

Results: The distribution of demographic and pathologic variables was similar in both groups. All procedures were technically successful, with a mean carotid flow reversal time of 22 minutes. Twenty-one (70%) and 23 patients (69.69%) were symptomatic in the transcervical and transfemoral groups, respectively (P=.869). After intervention, new postprocedural DW-MRI ischemic infarcts were found in four transcervical (12.9%) and in 11 transfemoral (33.3%) patients (P=.03), without new neurologic symptoms. No major adverse events occurred at 30 days after the intervention. All patients remained neurologically intact, without an increase in stroke scale scoring. All stents remained patent, and all patients remained stroke-free during follow-up. In multivariate analysis, age (relative risk [RR], 1.022; P<.001), symptomatic status (RR, 4.109; P<.001), and open-cell vs closed-cell stent design (RR, 2.01; P<.001) were associated with a higher risk of embolization in the transfemoral group but not in the transcervical group.

Conclusions: These data suggest that transcervical carotid stenting with carotid flow reversal carries a significantly lower incidence of new ischemic brain infarcts than that resulting from transfemoral CAS with a distal filter. The transcervical approach with carotid flow reversal may improve the safety of CAS and has the potential to improve results in especially vulnerable patients such as the elderly and symptomatic.