Influence of stent design and material composition on procedure outcome

Abstract

Although intravascular stents have received widespread application, significant limitations remain. In stent restenosis, the most pervasive problem affecting stents, is related in part to technical aspects of the device. Design features of the stent that influence outcome have been identified and optimized for improved performance. The influence of stent materials on critical aspects of healing, such as thrombotic, inflammatory, and hyperplastic responses, are less well understood. For this reason, significant progress in this area is lacking. Current stents have significant contamination with industrial impurities on the surface and in the bulk. This fact adds to the difficulties in interpreting the biologic reaction of the host to the device. Better understanding of the basic biologic interactions is the path to significant improvement.

Coronary Arterial Drug-Eluting Stent: From Structure to Clinical

“…Recently, an in vitro study suggested that a stent surface with a microscopic pattern of parallel grooves disposed in the direction of blood flow leads to a faster re-endothelialization process than the stent with smooth surface 75 . In addition, in a recent animal study, a similar result was observed a stent with a microscopic parallel grooves accelerated the endothelialization rate significantly 1 week after implantation in porcine carotid arteries compared to smooth stents 76,77 . In order to www.intechopen.com determine the relationship between the stent surface topography and outcome in patients undergoing implantation of stents with rough and smooth surfaces, a clinical trial of 200 patients with significant stenosis in native coronary vessels were randomly assigned in a double-blind study to receive either a rough or a smooth-surface stent.…”

Efficacy and Safety of a Novel Bioabsorbable Polymer-Coated, Everolimus-Eluting Coronary Stent

“…2 Whether metal alloy coronary stent platforms with bioresorbable polymers are associated with improved clinical outcomes when compared with newer durable polymer DES has been the subject of debate 3,4 and may be influenced by additional factors, including stent strut thickness, polymer composition, distribution, and load. 5 Although current American College of Cardiology/ American Heart of Association (ACC/AHA) clinical practice guidelines recommend at least 12 months of dual antiplatelet therapy (DAPT) after DES deployment in patients who are not at increased risk for bleeding, 1 recent studies suggest that even longer duration DAPT therapy (≥30 months) provides EVOLVE II 12-Month Primary End Point additional ischemic event reduction. 6 The SYNERGY stent (Boston Scientific Corporation, Marlborough, MA) is a novel thin-strut platinum chromium (PtCr) metal alloy stent that elutes everolimus from an ultrathin bioabsorbable Poly(D,Llactide-co-glycolide) polymer applied to the abluminal surface.…”

“…5,24,25 In this regard, the SYNERGY stent was designed to enhance/expedite stent healing in hopes of improving clinical outcomes by incorporating thin (74 μm) PtCr struts with an ultrathin (4 μm) Poly(D,L-lactide-co-glycolide) everolimus-eluting polymer applied only to the abluminal stent surface and which is resorbed within 4 months. 7,26 The bare metal PtCr platform which remains after polymer resorption may be less proinflammatory in cell assay when compared with gold, CoCr, or cobalt nickel alloy platforms, and seems to both expedite endothelial cell stent coverage and reduce platelet adhesion when compared with PtCr covered by polyvinylidene fluoride durable polymer.…”

Sustained increased risk of adverse cardiac events over 5 years after implantation of gold‐coated coronary stents

“…Stent characteristics have been traditionally attributed an important role in the outcome of patients undergoing coronary stent placement [1,2] and, therefore, they have been at focus of many experimental and clinical studies [3][4][5][6][7][8]. Furthermore, specific recommendations have been provided to guide stent manufacture to limit thrombotic, inflammatory, and hyperplastic responses after implantation as well as facilitate stent placement by improving radiopacity [9].…”