N-Terminal Prohormone of Brain Natriuretic Peptide (NT-proBNP) as a Diagnostic Biomarker of Left Ventricular Systolic Dysfunction in Patients with Acute Exacerbation of Chronic Obstructive Pulmonary Disease (AECOPD)

Left ventricular systolic dysfunction (LVSD) and cardiac decompensation often accompany AECOPD. Differentiation between the two is difficult and mainly relies on clinical and echocardiographic diagnostic procedures. The value of biomarkers, such as NT-proBNP, as diagnostic tools is still insufficiently investigated. The main goals of this trial were to investigate the value of NT-proBNP as a diagnostic tool for LVSD in AECOPD patients and determine its cut-off value which could reliably diagnose LVSD during AECOPD. This trial prospectively enrolled 209 patients with AECOPD. The patients were divided into four groups-AECOPD plus chronic pulmonary heart disease (CPHD) with or without left ventricular compromise (LVSD), and AECOPD patients without CPHD with or without LVSD. NT-proBNP was measured within first 48 h of hospitalization. Majority of patients were male (61%) active smokers (41.6%), average age of 68 years. High quality of echocardiography was obtained in 63.3 and 22.5% of the patients had LVSD. Average value of NT-proBNP in patients with LVSD was 3303.2 vs. 1092.5 pg/mL in patients without LVSD. Significant differences in NT-proBNP value (p = 0.0001) were determined between observed patient groups. At the cut-off value of 1505 pg/mL, sensitivity, specificity, and positive and negative predictive values are 76.6, 83.3, 57.1, and 92.47%, respectively. At the cut-off value of 1505 pg/mL NT-proBNP could be used as a diagnostic marker for LVSD in acute exacerbation of COPD.