N-Terminal Pro-B Type Natriuretic Peptide Imply Left Ventricular Diastolic Function but is a Low Sensitivity Marker

Abstract

Purpose Correlations between NT-proBNP with diastolic echocardiographic parameters were not analyzed precisely. We sought to evaluate the clinical implication of NT-proBNP on the LV diastolic function in large scale databases. Methods NT-proBNP(n=23,029) and echocardiography databases(n=48,750) were collected. Cases measured within 24 hours were enrolled and increased serum creatinine level(>2.0 pg/ml) or acute coronary syndrome were excluded. Finally, echocardiographic parameters were compared with serum NT-proBNP levels in 1,852 patients. Results Among patients (54% female, mean age 63.0±0.3), 460 patients (24.8%) showed preserved LV systolic functions (LVEF ≥40%, 53.5±0.4%). NT-proBNP levels were significantly correlated with LVEF(r=-0.52, p=0.01), LA volume index(r=0.50, p=0.01), E/E’(r=0.44, p=0.01), RV systolic pressure (r=0.43, p=0.01) and LV mass index(r=0.40, p=0.01). NT-proBNP showed low sensitivities to determine E/E’ ratio above 15 and LAVI above 27 on cut-off values of the ROC curve with specificity of 80% (51.7% at 686.6 ng/L, 58.7% at 643.1 ng/L). Interestingly, in patients with preserved systolic function (55.9% male, mean age 61.2±0.7), NT-proBNP showed slightly high sensitivity than in total study group (53.5% at 717.0 ng/L, 60.9% at 443.3 ng/L). Conclusion Although NT-proBNP was proved as a useful parameter for assessing LV diastolic function as well as systolic function, it showed relatively low sensitivity to determining LV diastolic function. Therefore, NT-proBNP may imply LV diastolic function but should be interpreted with combining clinical informations.