An overview of polymer-based-bioresorbable drug-eluting stents

Coronary artery disease treatments like coronary artery bypass grafting and percutaneous transluminal coronary angioplasty have several drawbacks, such as their invasive nature. Two main types of stents, bare metal stents (BMSs) and drug-eluting stents (DESs), are implemented to overcome these difficulties. The BMS offers strong mechanical support but can cause in-stent thrombosis and restenosis. Conventional DES, comprising a metal platform coated with drug-conjugated polymers, initially lowers restenosis but can cause early thrombosis and late in-stent restenosis. To overcome these limitations, biodegradable DESs are being explored to provide short-term support without long-term complications. However, biodegradable metal-based DES can trigger immunogenic reactions when degraded. The next generation of stents is shifting toward bioresorbable polymer-based DES because their degradation products are compatible with the metabolic system of the body. This review discusses the in vivo degradation mechanisms of bioresorbable polymers such as polyglycolic acid, polylactic acid, and polycaprolactone (PCL) acid polymers. It was observed that these polymers primarily degrade via ester bond hydrolysis, influenced by polymer properties such as molecular weight, morphology, glass transition temperature, and composition. Additionally, this overview highlights ongoing advancements in bioresorbable polymer-based scaffolds like DESolve[Formula: see text]NX and FANTOM[Formula: see text]. These bioresorbable scaffolds are fabricated from poly-L-lactide acid and desamino tyrosine-based polymers, respectively. Polylactic-co-glycolic acid-coated platinum–chromium stents have also demonstrated effective performance, being fully absorbed within 4–6 months postimplantation. Moreover, PCL acid-based drug-eluting bifurcation stents have shown promise in treating cardiovascular diseases. However, the review emphasizes the necessity for continued research to address the existing challenges and enhance patient outcomes.