Intraprocedural and Delayed Plaque Protrusion in Carotid Artery Stenting Using a Dual-Layer Metallic Stent.

Background: Intravascular ultrasound-determined plaque protrusion (PP) during carotid artery stenting (CAS) using conventional stents is reported in 7.6% to 12% of cases and is associated with periprocedural cerebral embolism. The Casper/Roadsaver stent (CRS) is a dual-layer micromesh stent designed to reduce the risk of PP, with a mesh cell diameter 4-fold smaller size than that of conventional stents. This study investigated the incidence of PP with CRS CAS. Methods: We prospectively analyzed 89 consecutive arteriosclerotic carotid artery stenoses in 82 patients (64 men; mean age, 76.8 years; 43 symptomatic) who underwent CAS with CRS under intravascular ultrasound. The main end points were the technical success rate, incidences of intraprocedural PP and at 1 week after CAS (delayed PP), incidence of new ipsilateral diffusion-weighted imaging lesion within 48 hours post CAS, and major adverse events (myocardial infarction, stroke, death) within 30 days. Secondary end points were the rate of in-stent restenosis and ipsilateral stroke at 30 days and 12 months. Results: The technical success rate was 100%. Intraprocedural PP occurred in 2 patients (2.2%). Delayed PP occurred in 3 additional patients (3.4%). Diffusion-weighted imaging positivity was 24.7%. Major adverse events (minor stroke) occurred in 1 patient (1.1%). In-stent restenosis occurred in 5 patients (6.0%) by 12 months. No ipsilateral stroke occurred during the follow-up. Conclusions: The incidence of intraprocedural PP with CRS CAS was 2.2%, indicating a significant reduction compared to conventional stents. However, at 7 days new PP had occurred in 3.4% of patients, indicating that patients with CRS should be followed up for delayed PP.