Comparison of Vessel Responses Following Combined Sirolimus-Eluting and Endothelial Progenitor Cell Stent and Ultra-Thin Sirolimus-Eluting Stent Implantation by Serial Optical Coherence Tomography and Coronary Angioscopy: A Multicenter Observational Study.

A dual-therapy sirolimus-eluting and CD34+ antibody-coated Combo Stent (DTS) has been developed to enhance endothelization and capture endothelial progenitor cells; however, vessel responses following DTS implantation remain unclear. Therefore, we evaluated early- and mid-term intravascular characteristics of DTS using intravascular imaging modalities. This multicenter, prospective, observational study enrolled 88 patients (95 lesions) who underwent DTS (43 patients, 48 lesions) or sirolimus-eluting Orsiro stent (SES, 45 patients, 47 lesions) implantation. Serial optical coherence tomography (OCT) and coronary angioscopy (CAS) findings were compared between the groups at 1 and 12 months.The OCT findings were similar between the DTS and SES groups at 1 month, including the covered strut rate (84.21 ± 9.50% versus 80.56 ± 17.68%, p = 0.27). CAS findings were also comparable despite a more severe yellow coloration observed in the DTS group (p = 0.006). At 12 months, OCT findings revealed that the covered and adequate strut coverage (≥40 μm) rates were significantly higher (99.27 ± 0.95% versus 95.46 ± 5.56%, p <0.001 and 88.90 ± 10.15% versus 72.96 ± 16.48%, p <0.001) and neointimal thickness was significantly thicker (152.16 ± 70.31 versus 84.39 ± 29.80 μm, p <0.001) in DTS than in SES. The malapposed strut rate was significantly higher in SES than in DTS (0.04 ± 0.18% versus 0.82 ± 1.87%, p = 0.018). CAS revealed that the yellow coloration (p = 0.049) and subclinical intrastent thrombus (p = 0.019) were less severe in DTS than in SES at 12 months. In conclusion, DTS provided better advantages regarding strut coverage and plaque stabilization compared to SES. However, given the observational nature of this study, further randomized controlled trials are needed to confirm these findings.