Home > DARE Reviews > Use of drug-eluting stents in acute...

PubMed Health. A service of the National Library of Medicine, National Institutes of Health.

Database of Abstracts of Reviews of Effects (DARE): Quality-assessed Reviews [Internet]. York (UK): Centre for Reviews and Dissemination (UK); 1995-.

Database of Abstracts of Reviews of Effects (DARE): Quality-assessed Reviews [Internet].

Use of drug-eluting stents in acute myocardial infarction: a systematic review and meta-analysis

SS Brar, MB Leon, GW Stone, R Mehran, JW Moses, SK Brar, and G Dangas.

Review published: 2009.

CRD summary

The authors concluded that the use of drug-eluting stents appeared safe and efficacious compared with bare-metal stents in patients with ST-segment elevation myocardial infarction. Overall, this review appeared to be well conducted, but it is difficult to assess the reliability of the findings without further information about the quality of the included studies.

Authors' objectives

To compare drug-eluting stents and bare-metal stents in patients with ST-segment elevation myocardial infarction.

Searching

MEDLINE, EMBASE, and the Cochrane Library were searched from January 2000 to October 2008 for studies published in any language; search terms were reported. A number of conference proceedings, websites, and review articles were searched. References were reviewed for additional relevant data.

Study selection

Randomised controlled trials (RCTs) and registry studies that compared drug-eluting stents (Cypher or Taxus) and bare-metal stents for mortality, myocardial infarction, target vessel revascularisation, and stent thrombosis in adult participants with ST-segment elevation myocardial infarction, were eligible for inclusion.

The drug-eluting stents evaluated in the included studies were sirolimus-eluting stents, paclitaxel-eluting stents, or both. The mean age of participants in included RCTs ranged from 59 to 63 years; the percentage with diabetes mellitus ranged from 10 to 21%. In included registry studies, the mean age of participants ranged from 58 to 68 years; the percentage with diabetes ranged from 9 to 40%.

Two reviewers selected the studies for inclusion.

Assessment of study quality

Quality of the studies was assessed in terms of trial size and single-center versus multicentre design.

The authors did not report how many reviewers conducted the assessment.

Data extraction

The number of events in each study was extracted using the intention-to-treat (ITT) procedure, which was used to calculate relative risks (RRs) and 95% confidence intervals (CIs). Where target vessel revascularisation was not reported, target lesion revascularisation was used. Data from all follow-up time periods were extracted from the trials. Whenever possible, adjusted treatment effects were used in the registry studies.

Two reviewers independently extracted the studies.

Methods of synthesis

Meta-analyses examining pooled relative risks with 95% confidence intervals were performed using the DerSimonian and Laird random-effects model. The authors also reported outcomes as the absolute risk difference, and calculated number needed to treat (NNT). Heterogeneity was assessed using the Cochrane Q statistic (less than or equal to 0.1 was considered significant) and the I2 statistic.

Sensitivity analyses were conducted to assess the effects of study quality (including trial size; single centre versus multicentre; length of follow-up). Subgroup analyses were conducted to evaluate clinical factors on the outcomes (e.g. duration of clopidogrel therapy). Each study was deleted from the analysis in turn to assess its influence on the effect size.

Meta-regression was performed to evaluate the variables that predicted each outcome.

Publication bias was assessed using funnel plots, Begg and Mazumdar correlation test, Egger's regression method, and the Duval and Tweedie 'trim and fill' method.

Results of the review

Thirteen RCTs (n=7,352 patients) and 18 registry studies (n=26,521 patients) were included in the review. All the RCTs reported methods for allocation concealment; only one RCT was reported to be double-blind. Mean follow-up in RCTs ranged from seven to 24 months; the mean follow-up in registry studies ranged from six to 36 months.

RCTs: There was no difference between drug-eluting stents and bare-metal stents for mortality (RR 0.89, 95% CI 0.70 to 1.14; 13 RCTs), myocardial infarction (RR 0.82, 95% CI 0.64 to 1.05; 13 RCTs) or stent thrombosis (RR 0.97, 95% CI 0.73 to 1.28; 13 RCTs), but there was a significant effect in favour of drug-eluting stents for target vessel revascularisation (RR 0.44, 95% CI 0.35 to 0.55; 13 RCTs). The number needed to treat with a drug-eluting stent was 14 patients (95% CI 11 to 21) to prevent one target vessel revascularisation. There was no statistical heterogeneity between the trials for all outcomes. Results were consistent by trial size, and differing follow-up periods. Single-centre trials indicated greater benefit for drug-eluting stents than multicentre trials, but the confidence intervals widely overlapped.

Registry studies: There was a significant reduction in mortality with drug-eluting stents within one year of the index percutaneous coronary intervention (RR 0.68, 95% CI 0.54 to 0.88; 11 studies), but not within two years. There was no significant difference between drug-eluting stents and bare-metal stents for myocardial infarction within one and two years from the index percutaneous coronary intervention. However, target vessel revascularisation was significantly reduced with drug-eluting stents within one (RR 0.54, 95% CI 0.40 to 0.74; 11 studies) and two years (RR 0.71, 95% CI 0.61 to 0.83; 10 studies) of the index percutaneous coronary intervention. There was also a significant difference in favour of drug-eluting stents for stent thrombosis within one year of the index percutaneous coronary intervention (RR 0.52, 95% CI 0.31 to 0.88; nine studies), but not within two years.

There was no evidence of publication bias for the RCTs, but there was evidence of publication bias for the registry studies.

Authors' conclusions

The use of drug-eluting stents appeared safe and efficacious compared with bare-metal stents across RCTs and registry studies of patients with ST-segment elevation myocardial infarction.

CRD commentary

The review addressed a clear question and was supported by appropriate inclusion criteria. Attempts to identify all relevant studies were undertaken by searching relevant databases and other sources; a rationale was provided for the limited search dates. The search was not restricted by language of publication, limiting the potential for language bias. Publication bias was explored in detail. Steps were taken to minimise reviewer error and bias in the review processes.

The authors did not present a thorough assessment of the quality of the RCTs; only some aspects of quality were considered in the analyses. Appropriate methods were used to pool the results and to investigate statistical heterogeneity.

Overall, this review appeared to be well conducted, but it is difficult to assess the reliability of the findings without further information about the quality of the included studies.

Six of the authors disclosed financial links with various stent manufacturing companies (Abbott Vascular, Boston Scientific, Cordis, Medtronic and The Medicines Company).

Implications of the review for practice and research

Practice: The authors did not state any implications for practice.

Research: The authors stated that trials with longer follow-up periods are needed to assess the robustness of the findings.

Funding

One author received research grant support from Boston Scientific (manufacturers of bare-metal and paclitaxel-eluting stents).

Bibliographic details

Brar SS, Leon MB, Stone GW, Mehran R, Moses JW, Brar SK, Dangas G. Use of drug-eluting stents in acute myocardial infarction: a systematic review and meta-analysis. Journal of the American College of Cardiology 2009; 53(18): 1677-1689. [PubMed: 19406344]

PubMedID

19406344

Indexing Status

Subject indexing assigned by NLM

MeSH

Confidence Intervals; Drug-Eluting Stents; Female; Humans; Male; Middle Aged; Myocardial Infarction /drug therapy /mortality /physiopathology /therapy; Registries; Regression Analysis; Risk

AccessionNumber

12009105186

Date bibliographic record published

16/09/2009

Date abstract record published

02/03/2011

Record Status

This is a critical abstract of a systematic review that meets the criteria for inclusion on DARE. Each critical abstract contains a brief summary of the review methods, results and conclusions followed by a detailed critical assessment on the reliability of the review and the conclusions drawn.

CRD has determined that this article meets the DARE scientific quality criteria for a systematic review.

Copyright © 2014 University of York.

PMID: 19406344

PubMed Health Blog...

read all...

Recent Activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...