A collaborative analysis of data from randomised trials of patients who underwent random allocation to either cobalt-chromium everolimus eluting stents or bare metal stents to assess the comparative safety and efficacy of these two devices on fatal and non-fatal cardiovascular outcomes.
Studies shown that after treatment with drug eluting stents compared with bare metal stents, the target vessel revascularisation rate is reduced because of angiographic restenosis and ischaemia. Because of that, most percutaneous coronary interventions are done with drug eluting stents rather than bare metal stents. The higher rates of late stent thrombosis and the concern about higher risks of late stent thrombosis after early discontinuation of dual antiplatelet therapy with first generation drug eluting stents, however, have raised safety concerns. New drug eluting stents have been developed with novel materials, designs, and delivery systems, with biocompatible polymers and new antiproliferative agents.
Individual patient data meta-analysis of randomised controlled trials. Cox proportional regression models stratified by trial, containing random effects, were used to assess the impact of stent type on outcomes. Hazard ratios with 95% confidence interval for outcomes were reported.
Participants receiving cobalt-chromium everolimus eluting stents had a significant reduction in below at a median follow-up of 720 days, compared with patients receiving bare metal stents.
- Cardiac mortality (hazard ratio 0.67, 95% confidence interval 0.49 to 0.91; P=0.01)
- Myocardial infarction (0.71, 0.55 to 0.92; P=0.01)
- Definite stent thrombosis (0.41, 0.22 to 0.76; P=0.005)
- Definite or probable stent thrombosis (0.48, 0.31 to 0.73; P<0.001)
- Target vessel revascularisation (0.29, 0.20 to 0.41; P<0.001).
- There was no significant difference in all cause death between groups (0.83, 0.65 to 1.06; P=0.14).
Findings remained unchanged at multivariable regression after adjustment for the acuity of clinical syndrome (for instance, acute coronary syndrome to stable coronary artery disease), diabetes mellitus, female sex, use of glycoprotein IIb/IIIa inhibitors, and up to one year to longer duration treatment with dual antiplatelets.