Overview and reanalysis of systematic reviews on invasive strategies for acute coronary syndromes

Article type
Authors
Kuukasjarvi P, Malmivaara A, Makela M
Abstract
Objectives: We aimed to collect all systematic reviews on invasive strategies for acute coronary syndromes (ACS) and reanalyse the review data.

Methods: Electronic databases were searched from 1994 to September 2004. We included systematic reviews of RCTs on patients with ACS. The methodological quality of the reviews was assessed. The main outcome parameters of the reviews were reanalysed by using fixed and random effect models. Bayesian models were constructed to further evaluate the uncertainty about a possible treatment effect.

Results: We found one systematic review on invasive strategies for unstable angina / non-ST-elevation myocardial infarction (UA/NSTEMI). Nine systematic reviews were identified on invasive strategies for ST-elevation myocardial infarction (STEMI) of which we included five reviews published after year 2000. Median quality score was 10.5 (range 7-13, n=6) on a scale from 0 to 18. Concerning mortality the average NNT for early routine invasive strategy on patients with UA/NSTEMI when compared with early selective invasive strategy to save one life varied between 82 and 100 patients. The average NNT for percutaneous coronary intervention (PCI) on STEMI when compared to fibrin specific thrombolysis to prevent one early death was 70-100 patients.

Conclusions: There is some evidence on small survival benefit on early invasive strategy for UA/NSTEMI, but also the risk of doing harm should be considered. There is evidence for PCI to marginally decrease early mortality after STEMI, but there is uncertainty of generalisability of the meta-analysis data to routine clinical praxis.