Surface chemical and physical modification in stent technology for the treatment of coronary artery disease

Abstract

Coronary artery disease (CAD) kills millions of people every year. It results from a narrowing of the arteries (stenosis) supplying blood to the heart. This review discusses the merits and limitations of balloon angioplasty and stent implantation, the most common treatment options for CAD, and the pathophysiology associated with these treatments. The focus of the review is heavily placed on research efforts geared toward the modification of stent surfaces for the improvement of stent-vascular compatibility and the reduction in the occurrence of related pathophysiologies. Such modifications may be chemical or physical, both of which are surveyed here. Chemical modifications may be passive or active, while physical modification of stent surfaces can also provide suitable substrates to manipulate the responses of vascular cells (endothelial, smooth muscle, and fibroblast). The influence of micro- and nanostructured surfaces on the in vitro cell response is discussed. Finally, future perspectives on the combination of chemical and physical modifications of stent surfaces are also presented.

Nano- and microstructured materials for in vitro studies of the physiology of vascular cells

“…Moreover, the material of choice should also be suitable for the fabrication method used to generate micro- and nanoscale topographies. To be compliant with cell experiments the materials have to be implicitly non-cytotoxic in in vitro cell studies, or should be biocompatible for (future) in vivo applications [3–4 48,83–86]. …”

“…There is a wide variety of materials including polymers, silicon, metals, ceramics, and composites made from various combinations of such materials [3,48,85–86]. Due to the vast amount of literature on different materials, only the most relevant materials used in studies with vascular cells are described below.…”

“…In vivo, the ECM where ECs and SMCs attach to, provide them micro- and nanotopographical stimuli to regulate their behavior [58]. Therefore, the in vitro investigation of cell type-specific functions and responses with vascular cells to surface topographies, either in the micrometer or in the nanometer range, provide new solutions to control the behavior of such cells and has already attained much interest [3,5,12,23–24 30–31 45,198]. Recent research has tried to elucidate mechanisms by which the independent stimulation of endothelial (ECs) and smooth muscle cells (SMCs) may be achieved by introducing surface topographies [8–12 199–200].…”

Biomaterials for Cardiac Regeneration

“…These stents had moderate success in limiting restenosis; however, they came with the added complication of preventing proper endothelial healing . The next step towards the use of truly biocompatible stents came in the form of micro-scale and nano-scale structuring of the stents to mimic natural endothelial function (Nazneen et al 2012 ).…”

“…This device material has admirable mechanical properties in addition to corrosion resilience (Nazneen et al 2012 ). Unfortunately, it has a tendency to induce thrombotic effects on its surface (Thierry et al 2002 ).…”