Short-term stent coverage of second-generation zotarolimus-eluting durable polymer stents: Onyx one-month optical coherence tomography study

Introduction: To date the early strut coverage with the second-generation durable-polymer ONYX zotarolimus-eluting stent (O-ZES) is unknown. Aim: Optical coherence tomography (OCT) assessed the strut coverage of O-ZES at thirty-day follow-up. Material and methods: OCT was performed after implantation and at 1-month follow-up in 15 patients treated with O-ZES. Results: Mean patient age was 67 +/- 7 years (73% males). The clinical presentation consisted of acute coronary syndromes (n = 13) and stable coronary disease (n = 2). Four (26%) patients had diabetes. OCT analysis was performed at baseline and 1-month follow-up in all stents. 378 cross-sections with 3582 struts were assessed at baseline and 3661 at follow-up. At follow-up, 88% struts were covered by tissue with a median thickness 37.91 mu m (IQR: 22.32-64.15). Median in-stent area obstruction by neointima was 2.64% (IQR: 1.70-4.84). From the total stent covered area, 92.3% showed complete strut coverage. Homogeneous tissue was observed in 74% of cases. There were no differences in minimal lumen area (5.07 +/- 1.08 mm(2) vs. 4.81 +/- 0.94 mm(2), p = 0.125) or minimal stent area (4.95 +/- 1.22 mm(2) vs. 4.92 +/- 0.99 mm(2)) at baseline and at follow-up. There were no differences in the rate of strut malapposition (4.3% vs. 5.7%, p = 0.417). For all stents, malapposition volume was 47.9 mm(3) at baseline and 51.7 mm(3) at follow-up, giving the late acquired stent malapposition volume of 3.8 mm(3). Conclusions: The second-generation durable polymer O-ZES showed favorable vessel healing at 30-day OCT follow-up.