Diagnostic significance of cardiac bridging integrator 1 score in hospitalized patients with heart failure with preserved ejection fraction and its assessment of prognostic value for major adverse cardiac events.

backgroundCardiac bridging integrator 1 (cBIN1) is a cardiomyocyte-specific protein critical for excitation-contraction coupling. The cBIN1 score (CS), derived from plasma cBIN1 levels, serves as a non-invasive biomarker reflecting myocardial microstructural integrity and is unaffected by systemic inflammation or BMI.

methodsA total of 108 HFpEF patients and 108 matched controls were retrospectively included. All subjects underwent clinical evaluation, echocardiography, and biochemical testing. Plasma cBIN1 was measured by ELISA, and CS was calculated. Multivariate logistic regression and ROC analyses were used to assess the diagnostic and prognostic value of CS for HFpEF and major adverse cardiac events (MACE) during 1-year follow-up. A sensitivity analysis was performed by excluding patients with chronic kidney disease or eGFR < 60 ml/min/1.73 m² to address renal-related confounding.

resultsCS levels were significantly higher in the HFpEF group (p < 0.001). LVEF, E/e', neutrophil-to-lymphocyte ratio (NLR), BNP, and CS were independently associated with HFpEF. CS showed positive correlations with BNP, sST2, left atrial diameter, and E/e', and a negative correlation with LVEF. ROC analysis yielded an AUC of 0.805 for CS in diagnosing HFpEF (sensitivity 70.4%, specificity69.4%, cutoff = 3.902). Diagnostic performance improved when CS was combined with BNP (AUC = 0.953) or sST2 (AUC = 0.834). During follow-up, patients with CS ≥ 3.902 had significantly increased MACE risk (OR = 4.318, p = 0.002), establishing CS as an independent prognostic marker. The sensitivity analysis confirmed these findings remained robust: CS retained independent diagnostic value for HFpEF and predictive value for MACE, with stable diagnostic performance of CS alone and in combination with BNP/sST2, and minimal variation in optimal cutoff.

conclusionCS is an independent diagnostic marker for HFpEF and predictor of MACE, correlating with established cardiac markers and echocardiographic parameters. Its diagnostic accuracy is significantly enhanced when combined with BNP or sST2, supporting its clinical utility in early diagnosis and risk stratification in HFpEF.