Characterization of myocardial infarction as an end point in two large trials of acute coronary syndromes.

Myocardial infarction (MI) is a key component of composite end points in trials that evaluate new therapies in non-ST-segment elevation acute coronary syndromes. Types of MI events in these trials have not been well characterized. A similar clinical-events classification process adjudicated all suspected MI end points in the PURSUIT and PARAGON B trials. All MI end points were classified as nonprocedural, related to percutaneous coronary intervention, or related to coronary artery bypass grafting. A total of 16,173 patients was enrolled in the 2 trials, and 1,802 MI end points occurred during a 30-day follow-up. Nearly 66% of MI end points were not related to percutaneous coronary intervention or coronary artery bypass grafting. Patients who had MI compared with those who did not had higher 30-day mortality rates (13.6% vs 2.3%, p <0.001) and 6-month mortality rates (18.4% vs 4.4%, p <0.001). Patients who had been randomized to glycoprotein IIb/IIIa inhibition showed trends toward fewer MI events regardless of type. Two-thirds of MI end points in 2 large trials of acute coronary syndrome were not related to procedure. All MI types were associated with worse short- and long-term outcomes. Characterization of the type of MI provides an opportunity for more informed interpretation of clinical trial results and improved planning for future trials.

Duke Scholars

Author Matthew Todd Roe Medicine, Cardiology

Author John Hunter Peel Alexander Medicine, Cardiology