Long-term safety of drug-eluting stents

Abstract

Stent implantation in coronary stenosis has revolutionized the treatment of coronary artery disease. The introduction of antirestenotic drug coatings further improved their efficacy in reducing target vessel revascularizations. With increasing use of drug-eluting stents (DES), stent thrombosis (ST) rose as potentially fatal major complication. Initially, the incidence of ST late after stent implantation seemed to be similar for DES and bare metal stents until several studies proved otherwise in first-generation DES. Since then, the design and components of DES have been changed and new polymers, drugs and different combinations of platelet inhibitors have been introduced to further improve the safety of DES. In this review, the authors focus on the relationship between DES, lesion anatomy, implantation technique and pharmacology to avoid the occurrence of ST. Furthermore, the relationship between dual antiplatelet therapy, bleeding rate and its significant impact on patient outcome is discussed. Finally, some promising future concepts are highlighted.

Keywords::

• drug-eluting stents
• efficacy
• future concepts
• major bleeding
• pathophysiology
• risk factors
• safety
• stent thrombosis

Financial & competing interests disclosure

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

No writing assistance was utilized in the production of this manuscript.

Key issues

• • Major bleeding and stent thrombosis (ST) are major safety issues in drug-eluting stents (DESs) with both having significant impact on long-term survival and major adverse cardiac event.

• • Late and very late ST occur constantly up to several years after DES implantation, represent continuous hazards for the patients.

• • Stent polymers and antirestenotic drugs can trigger chronic inflammatory processes and promote the coagulation pathway.

• • Modern DES is noninferior to bare metal stents regarding the occurrence of ST.

• • Incomplete stent apposition is strongly linked with the development of late ST serving as potential nidus for thrombus formation.

• • The ideal duration of dual antiplatelet therapy is controversial. So far, there is no evidence for an improved survival with dual antiplatelet therapy duration of more than 12 months.

• • Biodegradable stents and drug-eluting balloons are promising concepts with unique features with respect to long-term safety that need to be tested in real-world populations.