Babapulle MN et al. (2004) A hierarchical Bayesian meta-analysis of randomised clinical trials of drug-eluting stents. Lancet 364: 583–591

Drug-eluting stents (DES) are designed to reduce the extent of in-stent restenosis following percutaneous coronary intervention (PCI), via the controlled elution of an antimitotic drug such as sirolimus or paclitaxel. Clinical trials investigating the benefits of DES over bare-metal stents (BMS), however, have been insufficiently powered to generate useful data on rates of mortality, myocardial infarction (MI) or other complications. Babapulle and colleagues have performed a meta-analysis of randomized trials in order to provide this information.

The authors identified 11 appropriate trials involving 5,103 patients, comparing the benefits and safety of DES (with sirolimus or paclitaxel) and BMS. All trials provided 6–12 months clinical follow-up after index PCI. Using a hierarchical Bayesian random-effects model, the team pooled the results, stratifying by the type of drug and presence of carrier polymer.

The pooled results indicated that mortality and MI occurred at similar rates for DES and BMS. Major cardiac adverse events, however, occurred at a lower rate in the DES group than in the BMS patients (7.8% vs. 16.4%; odds ratio (OR) 0.42; 95% credible interval (CI) 0.32–0.53), as did angiographic restenosis (8.9% vs 29.3%; OR 0.18; 95% CI 0.06–0.40).

The authors conclude that sirolimus-eluting and polymeric paclitaxel-eluting stents are superior to BMS in reducing the rates of angiographic restenosis and major cardiac adverse events, although no clear benefit has been shown in terms of a reduction in mortality or MI rates.