Cost-effectiveness of drug-eluting stents: if only all things were equal

They reduce rates of restenosis but not mortality or infarction — so are they worth it?

The development of drug-eluting coronary stents has proven to be a quantum advance in interventional cardiology, rivalling the impact of stenting itself. Drug-eluting coronary stents deliver effective local concentrations of antiproliferative drugs (thus avoiding systemic toxicities), without substantially modifying the technique of percutaneous coronary intervention (PCI). Two of the drugs used are sirolimus and paclitaxel. Sirolimus is an inhibitor of the G1-phase of the cell cycle, while paclitaxel inhibits microtubule formation, both of which are necessary for cell division. Thus, they inhibit the natural healing mechanisms — endothelial cell migration and extracellular matrix formation — that produce intimal hyperplasia, resulting in restenosis.