Aims: This study aimed to establish the early healing and neointimal transformation profile of the new polymer-free BioFreedom stent through sequential optical coherence tomography (OCT) within the first nine months following stent implantation.
Methods and results: We randomly assigned 104 BFS recipients to one of five groups with angiography and OCT follow-up at 1, 2, 3, 4, or 5 months, together with another follow-up for all at nine months. The primary endpoint was the degree of OCT-detected strut coverage at nine months. From 1, 2, 3, 4, and 5 months, median neointimal strut coverage increased from 85.8, 87.0, 88.6, 96.8 to 97.1%, respectively, to 99.6% (IQR 98.2-99.9) at nine months. At nine months, median percent neointimal volume was 13.0% and angiographic late lumen loss was 0.21±0.30 mm. Major adverse cardiac events (MACE) were limited to one non-cardiac death, one non-ST-elevation myocardial infarction not related to BFS, and two target lesion revascularisations without stent thrombosis (MACE rate 4.0%).
Conclusions: Neointimal strut coverage of the BFS was rapid and the BFS was shown to be clinically safe and effective.