Safety and Efficacy of Cobalt Chromium Everolimus-Eluting Stents for Treatment of In-Stent Restenosis: An ILUMIEN IV Substudy

BACKGROUND: The optimal management strategy for in-stent restenosis (ISR) remains unclear. We aimed to determine the safety and efficacy of percutaneous coronary intervention with XIENCE cobalt chromium everolimus-eluting stents (EES) for treatment of ISR. METHODS: In the ILUMIEN IV (Optical Coherence Tomography Guided Coronary Stent Implantation Compared to Angiography: A Multicenter Randomized Trial in Percutaneous Coronary Intervention) trial, the 1-year outcomes of all randomized patients with a single diffuse or multifocal single-layer ISR lesion treated with EES were compared with a performance goal. The primary end point was target lesion failure, the composite of cardiac death, target vessel-myocardial infarction, or ischemia-driven target lesion revascularization. Outcomes in patients with a single EES-treated ISR and non-ISR lesion were also compared. RESULTS: From May 2018 through December 2020, 247 patients with a single ISR lesion were treated with EES. Target lesion failure at 1 year occurred in 18 patients (7.4% [upper 1-sided 97.5% CI, 11.5%]), which was lower than the predefined performance goal of 20% (P<0.001). Compared with non-ISR lesions treated with EES (n=2021), the postpercutaneous coronary intervention minimal stent area by optical coherence tomography was smaller in treated ISR lesions (5.0±1.8 mm2 versus 5.6±1.9 mm2; P<0.001), but minimum stent expansion was similar (78.8±18.0% versus 79.0±16.9%; P=0.87), as was 1-year target lesion failure (7.4% versus 4.7%; hazard ratio, 1.58 [95% CI, 0.95–2.61]; P=0.07). CONCLUSIONS: XIENCE EES was safe and effective for treatment of single-layer ISR. Compared with non-ISR lesions, ISR lesions treated with EES had a smaller postpercutaneous coronary intervention minimal stent area although stent expansion and 1-year target lesion failure rates were not different.