Preclinical Study Investigates Effect of DES Drug at Stent Fracture Sites

October 30, 2018—CBSET, a preclinical research institute dedicated to biomedical technologies, announced that its scientists have published “Fracture in drug-eluting stents increases focal intimal hyperplasia in the atherosclerosed rabbit iliac artery” by Claire Conway, PhD, et al online ahead of print in Catheterization and Cardiovascular Interventions. According to CBSET, the data and analyses "illustrate differences in the dynamic healing responses to fractured and intact stents implanted in healthy and disease rabbit models."

In CBSET's announcement, Dr. Conway commented, “Despite clinical and autopsy reports of fractures in drug-eluting stents (DES), and associated risks including in-stent thrombosis and restenosis, it has not been established whether stent fracture is the cause of increased neointimal response. To test the hypothesis that coated drug at stent fracture sites accentuates neointimal response to fractures, our study employed pre-eluted stents as drug-free, yet polymer-coated, controls. The data show that stent fracture increases intimal hyperplasia post-DES implant, with increasing severity in arteries exhibiting more advanced disease.”

Senior Investigator Elazer Edelman, MD, PhD, explained, “The accentuation of stent strut fracture-induced vascular injury by drug eluted from the stents is intriguing—the proverbial adding salt to the wound. Time will tell how our findings for conformal polymer-coated stents extend to newer stent designs that employ absorbable coatings or deploy drug microparticles away from the struts.” Dr. Edelman is Chairman and Cofounder of CBSET.

Rami Tzafriri, PhD, CBSET's Director of Research and Innovation, added, “These findings could potentially have a seminal effect on development of innovative DES coating designs to treat coronary artery disease. Animal models of real-world scenarios such as stent fracture offer an exciting opportunity to differentiate the relative effectiveness of novel DES designs that may appear equivalent in simple lesions.”