Drug-eluting stents versus bare metal stents for angina or acute coronary syndromes.

BACKGROUND: Coronary artery stents are tiny tubular devices used to 'scaffold' vessels open during percutaneous transluminal coronary angioplasty (PTCA). Restenosis (re-narrowing) of vessels treated with stents is a problem; in order to reduce restenosis, stents that elute drugs over time are now available. However these drug-eluting stents are more expensive and there is a need to assess their clinical benefits prior to recommending their use. OBJECTIVES: To examine evidence from randomised controlled trials (RCTs) to assess the impact of drug eluting stents (DES) compared to bare metal stents (BMS) in the reduction of cardiac events. SEARCH STRATEGY: The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2008, Issue 4), MEDLINE (1990 - April 2009) and EMBASE (1980 - January 2009) were searched. We carried out handsearching (electronic and manual) up to January 2008. SELECTION CRITERIA: We included RCTs comparing DES with BMS used in conjunction with PTCA techniques in the review. Participants were adults with stable angina or acute coronary syndrome (ACS). We considered published and unpublished sources and included them if they reported outcome data of interest. DATA COLLECTION AND ANALYSIS: Three review authors independently extracted data, assessed trial quality assessment and checked decisions within the group. Data extraction included composite event rates (major adverse cardiac event, target vessel failure); death; acute myocardial infarction (AMI); target lesion revascularisation (TLR); target vessel revascularisation (TVR) and thrombosis. Data synthesis included meta-analysis of composite event rate, death, AMI and revascularisation rates, presented as odds ratios with 95% confidence intervals (CI) using a fixed-effect model. We assessed heterogeneity between trials. MAIN RESULTS: We included more than 14,500 patients in 47 RCTs. There were no statistically significant differences in death, AMI or thrombosis between DES and BMS. For composite events, TLR and TVR reductions were evident with use of sirolimus, paclitaxel, everolimus, dexamethasone, zotarolimus and (to a limited extent) tacrolimus-eluting stents. These effects are demonstrated in the longer term follow up. Subgroup analyses (e.g. diabetics) largely mirrored these findings. AUTHORS' CONCLUSIONS: Drug-eluting stents releasing sirolimus, paclitaxel, dexamethasone and zotarolimus reduce composite cardiac events. However, this reduction is due largely to reductions in repeat revascularisation rates as there is no evidence of a significant effect on rates of death, MI or thrombosis. The increased cost of drug-eluting stents and lack of evidence of their cost-effectiveness means that various health funding agencies are having to limit or regulate their use in relation to price premium.

The clinical effectiveness of central venous catheters treated with anti-infective agents in preventing catheter-related bloodstream infections: a systematic review.

OBJECTIVES: To assess the clinical effectiveness of central venous catheters (CVCs) treated with anti-infective agents (AI-CVCs) in preventing catheter-related bloodstream infections (CRBSI). DATA SOURCES: MEDLINE (OVID), EMBASE, SCI//Web of Science, SCI/ISI Proceedings, and the Cochrane Library. STUDY SELECTION: A systematic review of the literature was conducted using internationally recognized methodology. All included articles were reports of randomized controlled trials comparing the clinical effectiveness of CVCs treated with AI-CVCs with either standard CVCs or another anti-infective treated catheter. Articles requiring in-house preparation of catheters or that only reported interim data were excluded. DATA EXTRACTION: Data extraction was carried out independently and crosschecked by two reviewers using a pretested data extraction form. DATA SYNTHESIS: Meta-analyses were conducted to assess the effectiveness of AI-CVCs in preventing CRBSI, compared with standard CVCs. Results are presented in forest plots with 95% confidence intervals. RESULTS: Thirty-eight randomized controlled trials met the inclusion criteria. Methodologic quality was generally poor. Meta-analyses of data from 27 trials assessing CRBSI showed a strong treatment effect in favor of AI-CVCs (odds ratio 0.49 (95% confidence interval 0.37-0.64) fixed effects, test for heterogeneity, chi-square = 28.78, df = 26, p = 0.321, I = 9.7). Results subgrouped by the different types of anti-infective treatments generally demonstrated treatment effects favoring the treated catheters. Sensitivity analyses investigating the effects of methodologic differences showed no differences to the overall conclusions of the primary analysis. CONCLUSION: AI-CVCs appear to be effective in reducing CRBSI compared with standard CVCs. However, it is important to establish whether this effect remains in settings where infection-prevention bundles of care are established as routine practice. This review does not address this question and further research is required.