Plasma BNP and eGFR: Distribution Trends and Functional Class Associations in Acute Heart Failure

Introduction: Acute heart failure (AHF) is a serious condition marked by reduced cardiac output, leading to symptoms like dyspnoea and fluid retention. Accurate diagnosis and prognosis are critical for improving outcomes. B-type natriuretic peptide (BNP) and estimated glomerular filtration rate (eGFR) are key biomarkers for assessing heart and kidney function, respectively. BNP indicates heart failure severity, while eGFR predicts outcomes due to the cardio-renal syndrome. This study evaluates the distribution of BNP and eGFR in AHF patients and their correlation with NYHA functional classes. Materials and Methods: A cross-sectional study was conducted at BSMMU from July 2012 to June 2013, involving 90 AHF patients aged 40–80 years, selected using Framingham Criteria. Patients with renal failure, hepatic disease, malignancy, or pregnancy were excluded. BNP and eGFR levels were measured, and NYHA class was determined based on symptoms. Data analysis was done using SPSS, with Spearman’s correlation assessing BNP-eGFR relationships (p<0.05). Results: Among 90 patients (77.7% male), median BNP levels increased with worsening NYHA class: 262 pg/mL in NYHA II, 925 pg/mL in NYHA III, and 3010 pg/mL in NYHA IV (p<0.001). eGFR decreased from 68.94 mL/min/1.73 m² in NYHA II to 44.55 mL/min/1.73 m² in NYHA IV (p<0.001). A strong negative correlation between BNP and eGFR (-0.65 to -0.80) was observed (p<0.001). Conclusion: BNP and eGFR are valuable in assessing AHF severity. Their combined analysis enhances risk stratification and guides treatment for better patient outcomes.