Inflammatory biomarkers may help improve the diagnostic evaluation of acute decompensated heart failure (ADHF). A diagnostic observational study, published in Frontiers in Cardiovascular Medicine, evaluated the diagnostic role of interleukin-6 (IL-6) in ADHF among patients without acute myocardial infarction (AMI). 

A total of 122 patients were included, including 58 patients with ADHF and 64 with chronic heart failure (CHF). Plasma IL-6 and N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels were measured. Logistic regression and receiver operating characteristic (ROC) curve analyses were performed to assess diagnostic performance.

Patients with ADHF had higher plasma levels of both IL-6 and NT-proBNP compared with those with CHF. IL-6 levels demonstrated positive correlations with NT-proBNP, heart rate, and left ventricular end-diastolic dimension, and an inverse relationship with left ventricular ejection fraction. After adjustment, IL-6 remained independently associated with ADHF (odds ratio [OR], 1.461; 95% CI, 1.053-2.028; P=0.023). The optimal IL-6 cut-off for ADHF diagnosis was 5.00 pg/mL, with a sensitivity of 81.0%, specificity of 87.5%, and a Youden index of 0.685.

These findings indicate that IL-6 is independently associated with ADHF and demonstrates diagnostic accuracy in patients without AMI. Combined use with NT-proBNP may improve diagnostic performance, although prospective validation is required.