Soluble Suppression of Tumorigenicity 2 (sST2) as a Diagnostic and Prognostic Marker in Acute Heart Failure and Sepsis: A Comparative Analysis

<b>Background:</b> Suppression of Tumorigenicity 2 (ST2), a member of the interleukin-1 receptor family, plays a crucial role in immune regulation. Elevated sST2 levels are associated with poor prognosis in various inflammatory and cardiovascular diseases, including acute heart failure (AHF), sepsis and transplant rejection. <b>Objectives and methods:</b> This study aimed to evaluate the diagnostic and prognostic accuracy of sST2, along with other biomarkers, such as high-sensitivity C-reactive protein (hs-CRP), N-terminal pro-B-type natriuretic peptide (NT-proBNP), procalcitonin (PCT) and mid-regional pro-adrenomedullin (MR-proADM), in patients with AHF, sepsis and AHF/sepsis overlap. <b>Results:</b> A cohort of 74 patients was analyzed, and comparison statistics revealed that sST2 levels were significantly higher in the AHF/sepsis group (113.88 ng/mL) compared to the AHF group (42.24 ng/mL, <i>p</i> = 0.024), while no significant difference was observed between sepsis and AHF groups (<i>p</i> = 0.10). Other biomarkers, including hs-CRP and PCT, showed significant differences between the AHF and AHF/sepsis groups. ROC curve analysis identified sST2 as a strong predictor of mortality and readmission, with high AUC values for 30-day readmission (0.821) and mortality (0.87). <b>Conclusions:</b> These findings suggest that combining biomarkers, including sST2, could improve the early diagnosis, risk stratification and management of critically ill patients with overlapping AHF and sepsis. Further studies with larger populations are needed to validate these findings and explore the potential of integrating these biomarkers into clinical practice.