Objective
We aimed to assess early neointimal healing by optical coherence tomography (OCT) 3 months after implantation of the ultrathin Orsiro® sirolimus‐eluting stent with biodegradable polymer.
Background
New generations of drug‐eluting stents with biodegradable polymer have been developed to avoid the continued vascular irritation of durable polymers.
Methods
In this prospective, open‐label study, 34 patients received an Orsiro® sirolimus‐eluting stent with biodegradable polymer. In a subgroup of patients (n = 15), the intervention was performed under OCT guidance. All patients underwent OCT‐examination at three months. The primary endpoint was 3‐month neointimal healing (NIH) score, calculated by weighing the presence of filling defects, malapposed and uncovered struts. Secondary endpoint was maturity of tissue coverage at 3 months.
Results
At 3 months, NIH score was 13.7 (5.4‐22), covered struts per lesion were 90% (84‐97%), malapposed struts were 2.7% (0.8‐5.4%) and rate of mature tissue coverage was 47% (42‐53%). No target lesion failure occurred up to 12 months. Patients with OCT‐guided stent implantation demonstrated a trend toward earlier stent healing as demonstrated by superior NIH scores (angio guided: 17.6% [8.8‐26.4]; OCT‐guided: 9.8% [4.0‐15.5]; mean difference −8, [95%CI: −18.7‐2.9], P = 0.123). This group had significantly more covered struts per lesion (angio‐guided: 86% [82‐90]; 95% [92‐99]; mean difference 9% [95%CI: 3‐15], P = 0.001).
Conclusion
The Orsiro® sirolimus‐eluting stent with biodegradable polymer shows early vascular healing with a high rate of strut coverage at 3‐month follow‐up. OCT guided stent implantation had a positive impact on early vascular healing.