Abstract 14907: Clinically Feasible Electronic Health Record Tool for Stratification of 1- to 3-Year Post-Myocardial Infarction Risk of Cardiovascular Events: The Intermountain Acute Coronary Syndromes Risk Scores

Abstract

Background: Randomized trials report that prolonged (>1 year) use of P2Y12 inhibitors with aspirin after myocardial infarction (MI) reduces stent thrombosis and cardiovascular (CV) events, including new MI, stroke, and CV death. Post-MI patients may benefit to a differing extent from long-term dual anti-platelet therapy (DAPT); thus, a method is needed to identify those at higher risk of CV events. Hypothesis: A low-cost, easy-to-use, and highly predictive risk stratification tool can be created to differentiate risk of CV events 1-3 years after MI. Methods: Patients surviving ≥1 year after an index MI who had ≥1 additional risk factor for MI were studied. Cox regression models were used to derive sex-specific Intermountain Acute Coronary Syndromes (IMACS) risk scores in 70% of patients (N=1,342 females; 3,047 males). Validation of IMACS scores was performed in the other 30% of patients (N=576 females; 1,290 males). Variables used in model creation were age, troponin I, B-type natriuretic peptide, hemoglobin A1c, and all components of the lipid panel, complete blood count, and comprehensive metabolic panel. The primary end point was a composite of CV death, MI, or stroke. Results: Age averaged 68.7±12 and 69.8±12 for females in the derivation and validation groups, respectively, and 63.6±12 and 63.9±12 for males. IMACS scores ranged from 0-11 for females (grouping scores of 0-2, 3-6, and 7-11 into low-, moderate-, and high-risk) and 0-14 for males (0-2, 3-7, 8-14). In the validation groups, IMACS categories stratified CV event risk (Figure). IMACS c-statistics for females were c=0.675 and c=0.734 in derivation and validation groups, respectively, and for males c=0.715 and c=0.672. Conclusion: Sex-specific IMACS risk scores strongly stratified 1- to 3-year post-MI risk of CV events. IMACS is an inexpensive electronic health record tool that empowers the evaluation of which post-MI patients may be the best candidates for more aggressive therapeutic management.