Background: The Resolute stent is a newly developed system with a bio-histocompatible polymer that allows programmed drug delivery up to 180 days. The aim of this intravascular ultrasound (IVUS) analysis was to evaluate the short- (4 months) and mid-term (9 months) efficacy using the Resolute stent.
Methods and results: Data were derived from the RESOLUTE trial, a prospective, multicenter, non-randomized, single-arm study to treat de novo native coronary artery lesions. This trial included 2 cohorts with different follow-up periods, and all enrollment patients in this trial received IVUS study. Follow-up IVUS was available in 24 patients (4-month group) and 88 patients (9-month group). Neointimal obstruction (%) was defined as neointimal volume divided by stent volume. Cross-sectional narrowing (CSN, %) was defined as neointimal area divided by stent area. No significant differences in vessel, lumen and stent volume at post-procedure were observed within stented segments between the 4- and 9-month follow-up groups. Although neointimal volume and % neointimal obstruction showed no significant difference between the 2 groups (% neointimal obstruction: 2.2 ± 2.5 vs 3.7 ± 4.0%, P=0.09), maximum CSN was significantly larger in the 9-month group. There were 7 cases of late incomplete stent apposition.
Conclusions: These IVUS results showed minimum growth of neointimal proliferation by the Resolute stent throughout the stented segment up to 9 months follow up.
Trial registration: ClinicalTrials.gov NCT00248079.