Bare-metal stent is a stent without a coating or covering (as used in covered stents drug-eluting stents). It is a mesh-like tube of thin wire. The first stents licensed for use in cardiac arteries were bare metal – often 316L stainless steel. More recent ('2nd generation') stents use cobalt chromium alloy. The first stents used in gastrointestinal conditions of the esophagus, gastroduodenum, biliary ducts, and colon were plastic; bare metal stents were first brought the clinic in the 1990s.
Drug-eluting stents are often preferred over bare-metal stents because the latter carry a higher risk of restenosis, the growth of tissue into the stent resulting in vessel narrowing.
^Palmerini T et al. Long-Term Safety of Drug-Eluting and Bare-Metal Stents: Evidence From a Comprehensive Network Meta-Analysis. J Am Coll Cardiol. 2015 Jun 16;65(23):2496-507. PMID 26065988. Lay summary
^ abJorge C, Dubois C Clinical utility of platinum chromium bare-metal stents in coronary heart disease. Med Devices (Auckl). 2015 Aug 27;8:359-67. PMID 26345228 PMCID 4556305