Abstract 9504: The Role of Highly Sensitive Cardiac Troponin T in the Diagnosis of Isolated Diastolic Dysfunction: Comparison with Natriuretic Peptides

Abstract

Introduction: Isolated diastolic dysfunction is a frequent entity but difficult to diagnose. Natriuretic peptides are used as a possible non-invasive parameter to diagnose isolated diastolic dysfunction. Recently, the highly sensitive cardiac troponin T (hs-TnT) has been developed. However, the significance of hs-TnT measurement in isolated diastolic dysfunction remains uncertain. The purpose of this study is to evaluate the correlation between echoardiographic diastolic function and hs-TnT or natriuretic peptides in patients with heart failure and preserved ejection fraction. Methods: Consecutive 196 patients with heart failure, who had a left ventricular ejection fraction ≥50%, were enrolled. Hs-TnT, B-type natriuretic peptide (BNP), and N-terminal pro-BNP (NT-proBNP) levels were measured simultaneously. Diastolic function was evaluated by echocardiography using mean E', which is the average of lateral and septal E'. Results: The linear regression analysis demonstrated that mean E' correlated with log hs-TnT (R=-0.423, p<0.0001), log BNP (R=-0.321, p<0.0001), and log NT-proBNP (R=-0.367, p<0.0001). We performed the receiver operating characteristics (ROC) curve analysis to predict the diastolic dysfunction, mean E' <10 cm/sec, by biomarkers (Figure). The area under the ROC curve (AUC) for hs-TnT was 0.80, with the highest discriminating sensitivity and specificity being 0.93 and 0.52, respectively at hs-TnT=0.004 ng/mL. The AUC for BNP was 0.63, with the highest discriminating sensitivity and specificity being 0.58 and 0.68, respectively at BNP=59.4 pg/mL. The AUC for NT-proBNP was 0.69, with the highest discriminating sensitivity and specificity being 0.70 and 0.64, respectively at NT-proBNP=125.4 pg/mL. Conclusions: The hs-TnT is better than BNP or NT-proBNP in the diagnosis of isolated diastolic dysfunction. The hs-TnT is suggested to represent minor and ongoing myocardial injury in patients with isolated diastolic dysfunction.