Background
: SPIRIT III is a pivotal, multicenter, 2:1 randomized, controlled trial comparing Everolimus-eluting cobalt-chromium alloy XIENCE™ V stents (EES) to Paclitaxel-eluting Taxus
™
stents (PES) in de novo native coronary artery lesions. Intravascular ultrasound (IVUS) was performed in a subset of Spirit III to further investigate the safety and efficacy profiles of EES.
Methods
: The SPIRIT III IVUS study enrolled 305 patients who received 359 stents (244 EES in 205 patients; 115 PES in 100 patients). Serial IVUS imaging was performed post-intervention and at 8 months follow-up. Late lumen area loss was calculated as minimum lumen area (MLA) at post-intervention minus MLA at follow-up. Volume index, defined as volume data divided by stent length, was obtained for vessel (VVI), stent (SVI), lumen (LVI), plaque (PVI), and neointima (NVI).
Results
: At baseline, the incidence of tissue prolapse, edge dissections, and incomplete stent apposition (ISA) were not significantly different between EES and PES (15.6 vs 19.7%, 1.3 vs 2.8%, and 31.8 vs 28.2%, respectively). At follow-up, edge dissections and late-acquired ISA were not significantly different between EES and PES (1.4 vs 3.1%, 1.7 vs 4.1%, respectively). EES showed significantly less neointimal hyperplasia and a trend toward larger follow-up lumen than PES (Table
), whereas no statistical interactions were observed between EES and serial changes for VVI and PVI. PES showed a significant increase in VVI and PVI between post-intervention and follow-up. Reference segment analysis showed no unfavorable edge effect adjacent to either EES or PES.
Conclusion
: Detailed IVUS analysis confirmed significantly greater neointimal suppression with EES, with no apparent adverse vessel response, as compared to PES. Additional drug-eluting stent trials in more complex lesions are warranted to further validate the clinical utility of these new technologies.
Intravascular Ultrasound Findings in the Multicenter, Randomized, Double-Blind RAVEL (RAndomized study with the sirolimus-eluting VElocity balloon-expandable stent in the treatment of patients with de novo native coronary artery Lesions) Trial
