Data presented at VIVA13 (Vascular InterVentional Advances), taking place in Las Vegas this week has demonstrated safety and promising clinical performance at twelve months in the treatment of patients with peripheral arterial disease (PAD) undergoing femoropopliteal artery intervention using Veryan Medical’s BioMimics 3D™ stent.
UK specialist vascular company Veryan Medical Ltd. has employed the principles of biomimicry in developing a stent with unique three dimensional helical geometry, which it calls BioMimics 3D™. We’ve followed with interest Veryan’s progress, most recently in September when the UK’s NIHR issued a report discussing the BioMimics device’s potential. The stent is designed to mimic the helical configuration of natural vessels and in so doing reduce the formation of neointimal hyperplasia.
The MIMICS study, presented at VIVA13 is a prospective, 2:1 randomised controlled trial, conducted at eight German investigational centres, comparing the safety and efficacy of the BioMimics 3D™ stent to a straight nitinol stent (primarily the Bard LifeStent) in 76 patients with PAD undergoing femoropopliteal artery intervention.
The BioMimics 3D stent, with its longitudinal helical configuration, is designed to promote swirling blood flow through the stented segment, which preclinical data have shown to significantly reduce the formation of neointimal hyperplasia, potentially conferring a vasoprotective effect through elevation of wall shear stress.
Data presented by PI Professor Thomas Zeller, Universitäts-Herzzentrum, Freiburg-Bad Krozingen, on behalf of the MIMICS investigators showed:
- 12-month Kaplan Meier (KM) estimate of freedom from clinically driven target lesion revascularization for subjects receiving the BioMimics 3D stent was 91.2%.
- The KM estimate of 12-month primary patency was 80.4% for BioMimics 3D subjects vs. 72.0% for the control group (day 365; P=0.436).
- No stent fractures were detected by core lab in BioMimics 3D or Control in 12-month X-rays.
- Twelve month data from the MIMICS study point to a correlation between primary patency and stent curvature, measured using bi-planar X-ray imaging in straight and bent knee positions.
- No loss of stent patency was observed in any subject where stent curvature measured >0.02 mm-1.
- Bi-planar X-ray imaging and computational fluid dynamic modelling showed increases in both swirling flow (55% (P=0.017)) and wall shear stress (18% (P=0.054)) for BioMimics 3D compared to Control.
- Interim 24-month data show that 76% of BioMimics 3D subjects gained a PSVR improvement between 12 and 24 months, which is 83% more than Control (P=0.067). Twenty four month follow-up assessments are ongoing.
These data provide support for the hypothesis that a stent with 3D geometric curvature will be patency-protective through development of swirling flow and elevation of wall shear stress. The helical geometry of the BioMimics 3D stent also enhances mechanical performance and biomechanical compatibility, intended to reduce stent fracture, vessel and stent kinking, deformation and subsequent vessel trauma during leg flexion, compared to straight nitinol stents.
“Data on the BioMimics 3D stent demonstrating promotion of swirling flow and increased wall shear stress, together with 12-month and emerging 24-month patency data, point to the merit of this innovative approach to stent design for femoropopliteal use” commented Professor Zeller. “We now need additional longer-term data to confirm these effects”.
Source: Veryan Medical Systems, Ltd.