Abstract 11021: Lack of Implementation of ESC/ACC Definition of Myocardial Infarction in Contemporary Randomized Clinical Trials
Introduction: Although myocardial infarction (MI) is a key metric in randomized clinical trials (RCTs) evaluating new therapies, heterogeneity in MI definition may affect comparisons across RCTs as well as meta-analyses. Hence we explored the extent to which the ESC/ACC consensus recommendations for MI definition are applied in contemporary, large RCTs
Methods: We performed a systematic review of RCTs with >500 patients that listed MI as part of the primary endpoint by searching ClinicalTrials.gov & MEDLINE for RCTs meeting these criteria that were initiated after the 2000 ESC/ACC MI redefinition publication. Search terms included: acute coronary syndrome, MI, percutaneous coronary intervention, coronary artery bypass grafting, coronary artery disease. We explored 3 key recommendations: 1) Use of troponin (Tn) to define endpoint MI, 2) separate reporting of spontaneous and procedural MI, and 3) infarct size reporting.
Results: Of 971 studies, 114 (12%) met inclusion criteria. Of these 35 (31%) RCTs had primary results including 202,656 patients. The table has details of RCTs, their primary endpoints and MI definitions. 10,227 MI events contributed a median 44% (IQR 27–61) of events in the primary composites, a % that decreased with increasing number of components in the primary composite. Tn was used to define MI in 15 RCTs (43%); 2 of these used Tn only if CKMB unavailable and 1 used Tn for procedural MI. 20 RCTs used only CKMB or CK. No RCT specified the 99th percentile as MI decision limit, and none reported spontaneous and procedural MI separately or infarct size
Conclusions: Although MI contributes significantly to primary outcome measures in contemporary RCTs, there is surprisingly little implementation of ESC/ACC recommendations for MI definition and reporting. Better understanding of this failure and appropriate strategies for uniform implementation and thereby clarification of the relevance of the MI endpoint in cardiovascular RCTs, are urgently required.
- © 2010 by American Heart Association, Inc.