The Emerging Paradigm of Stent Biocompatibility: Current Status and Future Directions Dr Miles Dalby Consultant Cardiologist Honorary Senior Lecturer Royal Brompton & Harefield NHS Trust Imperial College

BiotonikSpeaker Bureau ConorSpeaker Bureau MSDSpeaker Bureau TransluminaResearch Grant Boston ScientificResearch Funding VolcanoResearch support Conflicts of Interest

What makes a good stent……. Acute performance: OK Anti-Restenotic Efficacy: OK Safety………………..n=????? t=?????

Evolution in Stent Biocompatibility Coated Bare Metal Stent: Prokinetic Drug Eluting Erodable Polymer Stent: Costar Bioabsorbable stent: Magic

316L steel stent tube in fibrinogen solution with applied current via electrode (time wrapping 1:10)(time wrapping 1:10) Silicon Carbide and Thromboresistance 316L A-SiC:H

Silicon Carbide Stainless Steel 0.5 µm 0.25 µm 0 µm 0.5 µm 0.25 µm 0 µm Silicon Carbide and Thromboresistance Biocompatibility

Silicon Carbide and Thromboresistance Chandler loop Silicon CarbideStainless Steel

Silicon Carbide and Endothelialisation Exposure of 316L and SiC to endothelial cells for 24h: Light microscopyAtomic Force Microscopy SiC 316L

Co-Star Paclitaxel eluting stent Bridge Elements Poly (lactide co-glycolide) Bioresorbable polymer Nanodroplet injection methodExplant at 180 days

Costar architecture and apposition: OCT

Costar Stent Overlap: OCT <100um Costar: Good acute performance (clinical experience and OCT) Fully absorbable Polymer resulting in BMS Platform for future drug release strategies 2 x 3mm 12 atm overlap no post dilatation Costar II Blind aggregate d30 MACE

Magnesium Alloy Bioabsorbable Stent Biocompatibility Imaging Re-Intervention Surgery ?Reduction in late thrombosis risk Return of vascular function

PROGRESS AMS-1: FIM %n%n%n MACE Death Q-wave MI Non Q wave MI Ischemic Driven TLR Primary Endpoint: Feasibility and safety at 4 months with MACE<30%. N=63 30-DayIn Hospital4-Month Negative Remodeling / Recoil

15 Months after AMS implantation in human IVUS OCT Courtesy of Pr. Carlo di Mario Very thin neointima perfect ingrow of AMS completed healing of the stented vessel

AB CD Bare Metal Stent Absorbable Metal Stent AMS: 16-row MSCT Compatible Lind et al Heart 91:1604, 2005

Stent Resorption and Vasoreactivity? Pre-ISDN Post-ISDN Stent segment

passivating matrix Mid / long term Addition of suitable drug Passivating coating Short term: AMS2 The future of the AMS platform Reduction of Degradation Rate Increase of Radial Force Optimization of mechanical stability Improved Geometrical Design Improved Alloy / Metallography Inhibition of side effects DREAMS Use AMS2 as basic platform