Abstract 10158: Evidence for Mortality Benefit of Bypass Surgery over Stenting Before Publication of the SYNTAX and FREEDOM Trials: Value of Meta-Analyses
Background: The recently published FREEDOM trial and the long-term results of the SYNTAX trial demonstrated significant unequivocal reductions in all-cause mortality with coronary artery bypass grafting (CABG) compared to percutaneous coronary intervention (PCI) in patients with multivessel disease. We sought to examine whether such mortality benefit of CABG over PCI with stenting was evident before these two landmark trials were published by performing a meta-analysis of antedating randomized controlled trials (RCTs).
Methods: A systematic literature search using PUBMED was conducted for all RCTs directly comparing CABG vs. PCI. To reflect the current practice, RCTs with > 1 arterial graft use in > 90% of the cases in the CABG arm and >70% stent use in the PCI arm that reported mortality in patients with multivessel disease were included. Trials using either bare-metal or drug-eluting stents could be included. Numbers of events at the longest possible follow-up and sample sizes were extracted. Fixed effect models were used to obtain meta-analytic risk ratios and 95% confidence intervals (CI).
Results: A total of 4 randomized trials published before SYNTAX and FREEDOM were identified (total n=3,060). On cumulative meta-analysis, the mortality benefit of CABG over PCI became statistically significant in 2008 with the publication of the SOS trial (Figure). Similarly, a statistically significant reduction in myocardial infarctions with CABG compared to PCI was apparent on cumulative meta-analysis before the publication of the 3-year results of SYNTAX and FREEDOM trials (RR=0.72 [95% CI: 0.54-0.96], p=0.027).
Conclusions: The mortality benefit of CABG over stenting in patients with multivessel disease was evident on meta-analysis even before the publication of SYNTAX and FREEDOM trials. Skillfully and timely performed meta-analysis of RCTs can provide invaluable information and can accurately predict the results of subsequent large-scale trials.
- © 2013 by American Heart Association, Inc.