Abstract 18850: Use of High Sensitivity Troponin Levels for Prediction of Myocardial Ischemia During Stress Testing

Introduction: Stress tests are routinely used for the detection of reversible myocardial ischemia. We determined the relationship between resting high sensitivity cardiac troponin I (hs-cTnI) levels and stress-induced myocardial ischemia (SMI) in patients with known coronary artery disease (CAD). Hypothesis: Patients with low hs-cTnI levels will not have reversible ischemia during stress. Methods: A discovery cohort of 581 patients and a validation cohort of 103 patients with stable CAD underwent 99mTc-SPECT myocardial perfusion imaging during treadmill exercise or pharmacologic stress testing and had pre-stress hs-cTnI levels measured (Abbott Labs). SMI was defined as a new or worsening impairment in myocardial perfusion using a 17-segment model. Sensitivity, specificity, and negative predictive value (NPV) were calculated. Results: The 34.9% of patients who developed SMI in the discovery cohort had higher hs-cTnI levels (5.4 [3.9-9.2] vs 3.9 [2.5-6.5] pg/mL, p<0.001). Low resting levels of hs-cTnI had a...