Abstract 15710: Sex-Specific High-Sensitivity Cardiac Troponin Thresholds for Rule-Out of Non-ST-Elevation Myocardial Infarction

Abstract

Introduction: The use of sex-specific cut-offs is recommended when high-sensitivity cardiac troponins (hs-cTn) are used for diagnosing acute myocardial infarction (MI). In this prospective, multi-centre study we evaluated the prognostic performance of sex-specific cut-offs for predicting low risk of MI in the Emergency Department (ED). Methods: 1895 patients (45% female) from two Norwegian centres where evaluated for potential non-ST-elevation myocardial infarction (NSTEMI). Cardiac troponins were tested with hs-cTnT (Roche) and hs-cTnI (Abbott and Siemens). Sex-specific differences in performance for a single-sample NSTEMI rule-out were investigated. Results: NSTEMI was diagnosed in 98 women (11.5%), 135 men (12.9%). Baseline hs-cTn concentrations were consistently lower in women compared to men, though not significantly so in the NSTEMI subgroup (Table 1). ROC curves showed consistent, though non-significantly, smaller AUCs for women compared to men with all three assays (Figure 1). Cut-offs for single sample rule-out aiming at >97% or >99% sensitivity for NSTEMI were evaluated. Women had consistently lower cut-off levels compared with men, with significantly lower (p < 0.001) Youden index for all three assays at >99% sensitivity and for the hs-cTnI assays at >97% sensitivity (Table 2). Conclusions: Sex-specific cut-offs for single sample rule-out should be considered in accelerated diagnostic protocols for evaluation of NSTEMI.