DAPT Score Utility for Risk Prediction in Patients With or Without Previous Myocardial Infarction

Abstract Objectives To determine whether a decision tool aids prescription of dual antiplatelet therapy duration in patients with or without prior myocardial infarction (MI) treated with coronary stents. Background The Dual Antiplatelet Therapy (DAPT) Study enrolled patients after coronary stenting. Patients randomized to continued thienopyridine and aspirin after 12 months had lower ischemic risk but higher bleeding risk than those treated with placebo and aspirin. The relative benefit and risk according to history of MI prior to stent treatment and additional utility of a decision tool (DAPT Score) is not well-defined. Methods Patients were categorized according to any history of MI prior to the index procedure, or no history of MI. Risk differences during the randomized treatment period (12-30 months) for ischemic (MI and/or stent thrombosis (ST)) and bleeding (GUSTO moderate/severe) events were compared according to DAPT Score. Results Rates of MI were 3.8% vs. 2.4%, P=0.01, for patients with any MI vs. no MI. Continued thienopyridine reduced late MI compared with placebo regardless of MI history (hazard ratios 0.46, P