BACKGROUND: The current generation of bioresorbable scaffolds has several limitations, such as thick square struts with large footprints that preclude their deep embedment into the vessel wall, resulting in protrusion into the lumen with microdisturbance of flow. The Mirage sirolimus-eluting bioresorbable microfiber scaffold is designed to address these concerns.
METHODS: In this prospective, single-blind trial, 60 patients were randomly allocated in a 1:1 ratio to treatment with a Mirage sirolimus-eluting bioresorbable microfiber scaffold or an Absorb bioresorbable vascular scaffold. The clinical endpoints were assessed at 30 days and at 6 and 12 months. In-device angiographic late loss at 12 months was quantified. Secondary optical coherence tomographic endpoints were assessed post-scaffold implantation at 6 and 12 months.
RESULTS: Median angiographic post-procedural in-scaffold minimal luminal diameters of the Mirage and Absorb devices were 2.38 mm (interquartile range [IQR]: 2.06 to 2.62 mm) and 2.55 mm (IQR: 2.26 to 2.71 mm), respectively; the effect size (d) was -0.29. At 12 months, median angiographic in-scaffold minimal luminal diameters of the Mirage and Absorb devices were not statistically different (1.90 mm [IQR: 1.57 to 2.31 mm] vs. 2.29 mm [IQR: 1.74 to 2.51 mm], d = -0.36). At 12-month follow-up, median in-scaffold late luminal loss with the Mirage and Absorb devices was 0.37 mm (IQR: 0.08 to 0.72 mm) and 0.23 mm (IQR: 0.15 to 0.37 mm), respectively (d = 0.20). On optical coherence tomography, post-procedural diameter stenosis with the Mirage was 11.2 ± 7.1%, which increased to 27.4 ± 12.4% at 6 months and remained stable (31.8 ± 12.9%) at 1 year, whereas the post-procedural optical coherence tomographic diameter stenosis with the Absorb was 8.4 ± 6.6%, which increased to 16.6 ± 8.9% and remained stable (21.2 ± 9.9%) at 1-year follow-up (Mirage vs. Absorb: dpost-procedure = 0.41, d6 months = 1.00, d12 months = 0.92). Angiographic median in-scaffold diameter stenosis was significantly different between study groups at 12 months (28.6% [IQR: 21.0% to 40.7%] for the Mirage, 18.2% [IQR: 13.1% to 31.6%] for the Absorb, d = 0.39). Device- and patient-oriented composite endpoints were comparable between the 2 study groups.
CONCLUSIONS: At 12 months, angiographic in-scaffold late loss was not statistically different between the Mirage and Absorb devices, although diameter stenosis on angiography and on optical coherence tomography was significantly higher with the Mirage than with the Absorb. The technique of implantation was suboptimal for both devices, and future trials should incorporate optical coherence tomographic guidance to allow optimal implantation and appropriate assessment of the new technology, considering the novel mechanical properties of the Mirage.
BACKGROUND: In interventional cardiology, the emergence of BRS technology is catalyzing the next paradigm shift.
METHODS: The MeRes-1 Extend was a multicenter, prospective, single-arm, open-label study enrolling 64 patients in Spain, Macedonia, Brazil, South Africa, Malaysia, and Indonesia. The safety endpoint was major adverse cardiac events (MACE) which composed of cardiac death, myocardial infarction (MI), and ischemia-driven target lesion revascularization (ID-TLR). The imaging efficacy endpoint was mean in-scaffold late lumen loss (LLL) evaluated by quantitative coronary angiography (QCA). Optical coherence tomography (OCT) imaging was performed at baseline and 6-month follow-up.
RESULTS: A total of 69 target lesions were identified in 64 enrolled patients (mean age 58.30 ± 9.02 years). Of the treated lesions, 49 (71.01%) lesions were of type B2/C. Procedural and device success was achieved in 64 and 62 patients, respectively. At 2-year follow-up, MACE was reported in one patient (1.61%) in the form of ID-TLR. There was no case of MI, cardiac death or scaffold thrombosis through 2-year. In a subset of 32 patients, paired QCA showed mean in-scaffold LLL of 0.18 ± 0.31 mm at 6-month follow-up. In a subset of 21 patients, OCT revealed 97.95 ± 3.69% strut coverage with mean scaffold area of 7.56 ± 1.79 mm2 and no evidence of strut malapposition.
CONCLUSIONS: The clinical and imaging outcomes of MeRes-1 Extend trial demonstrated favorable safety and efficacy of MeRes100 sirolimus-eluting BRS in patients with de novo coronary artery lesions.