Aims: Because of the reduction in the rate events related with in-stent restenosis, most events after drug-eluting stent implantation occur shortly after coronary stenting. Cobalt-chromium alloys allow to reduce strut thickness and improve flexibility and deliverability of coronary stent platforms, and thus could be associated with lower short-term events after stenting. The aim of this study was to test the hypothesis that drug-eluting coronary stents with a cobalt-chromium platform reduce the incidence of periprocedural (30-day) myocardial infarction in comparison with stainless steel drug-eluting coronary stents.
Methods and results: A meta-analysis from nine randomised trials comparing cobalt-chromium and stainless steel drug-eluting coronary stents that overall included 11,313 patients was performed. The incidence of myocardial infarction, stent thrombosis, and cardiac death at 30 days was compared between both types of stents. At 30 days, the incidence of acute myocardial infarction was significantly lower in patients allocated to cobalt-chromium drug-eluting stents (2.3% vs. 3.9%, respectively; p=0.006; odds ratio 0.72, 95% confidence interval 0.58-0.91), due to a significant reduction in the rate of non-Q-wave myocardial infarction (odds ratio 0.67, 95% confidence interval 0.51-0.88). The incidence of stent thrombosis was similar between both groups of patients, (0.5% vs. 0.5%, p=0.76; odds ratio 1.09, 95% confidence interval 0.63-1.89).
Conclusions: Drug-eluting coronary stents that use cobalt-chromium stent platforms have a better safety profile at 30 days in comparison with stainless steel drug-eluting stents, due to a significant reduction in the rate of myocardial infarction.