Abstract 11655: Can Blood Biomarkers Predict Whose Heart is Healthy? - Discriminatory Capacity of High-sensitivity Troponin T and C-reactive Protein Between Patients With and Without Coronary Atherosclerosis, LV Hypertrophy/Dysfunction and Myocardial Perfusion Abnormalities as Assessed by Cardiac CT and SPECT Imaging
Background: High-sensitivity troponin T (hsTnT) and C-reactive protein (hsCRP) are associated with cardiovascular events and structural heart disease. However, it is unclear whether these biomarkers can predict which patient is cardiac healthy.
Methods: We included patients with acute chest pain but without ACS who underwent both, contrast enhanced cardiac CT and stress SPECT myocardial perfusion imaging during the index care period. HsTnT and hsCRP were measured at time of CT scan. Diagnostic testing data was assessed for coronary atherosclerosis, LV hypertrophy/dysfunction and myocardial perfusion abnormalities. Patients were stratified into those with or without any of these findings, defined as being cardiac healthy. For each biomarker, a low cut-off corresponding to good specificity and high cut-off corresponding to good sensitivity for cardiac health were derived and discriminatory capacity of single- and dual-biomarker strategies determined.
Results: Among 117 patients (52 years, 55% male) included in this study, 42 (36%) were free of any cardiac disease. These cardiac healthy patients had significantly lower hsTnT and hsCRP levels as compared to those with cardiac disease (3.58 vs. 5.63 ng/L, p=0.002; 0.82 vs. 1.93 mg/L, p=0.0005; respectively). We determined hsTnT <3.00 ng/L and hsCRP <0.45 mg/L as highly specific lower cut-points. Patients with both, low hsTnT and low hsCRP (N=9) had a probability of 85% for being cardiac healthy. In contrast, patients above both high cut-offs (hsTnT >7.00 ng/L and hsCRP >2.00 mg/L; N=18) had a probability of 8% for being cardiac healthy. Discriminative capacity of a dual biomarker strategy was significantly improved compared to hsTnT or hsCRP alone and to FRS (AUC: 0.781 vs. 0.691; vs. 0.678; vs. 0.649; all p≤0.02 respectively).
Conclusion: A dual biomarker strategy of hsTnT and hsCRP is highly discriminative and predicts whose heart is healthy. Therefore, it may serve as a gatekeeper for diagnostics and treatment.
- © 2012 by American Heart Association, Inc.