Clinical trials versus registries in coronary revascularization: which are more relevant?

Clinical decision-making in coronary artery disease relies heavily on evidence-based medicine. Data from randomized controlled trials constitute the highest order of evidence and remain the standard for comparisons between therapies. While comprehensive, observational databases lack the scientific rigor of randomized controlled trials, they represent a more accurate accounting of everyday clinical care. Which data are more relevant to clinical practice?.

At least 11 randomized controlled trials and three meta-analyses comparing coronary artery bypass grafting and percutaneous coronary intervention exist, which all largely show no difference in death or myocardial infarction between the two treatments but more repeat revascularization with percutaneous coronary intervention. All these studies, however, are subject to the biases of trial design, which impact the external validity of the results. Analyses of four observational databases show a survival advantage in multivessel disease with coronary artery bypass grafting. Although these are reflective of real world clinical practice, they are subject to 'treatment bias', some of which can be corrected by risk adjustment.

Information from both randomized controlled trials and outcomes databases is necessary to determine appropriate strategy for individual patients. Reliance on data solely from either source is insufficient. It is incumbent on the treating physician to know not only the results of published studies, but also the limitations of that information.