B-Type Natriuretic Peptide Strongly Reflects Diastolic Wall Stress in Patients With Chronic Heart Failure

OBJECTIVES: We explored the stimulus for B-type natriuretic peptide (BNP) secretion in the clinical setting of heart failure (HF). BACKGROUND: Increasingly, plasma BNP levels are being incorporated into the clinical assessment and management of systolic heart failure (SHF) as well as diastolic heart failure (DHF). However, heterogeneity in BNP levels among individuals with HF can cause some confusion in interpreting results. METHODS: In 160 consecutive patients presenting with HF, we measured plasma BNP levels and performed echocardiography and cardiac catheterization. Systolic and diastolic meridional wall stress was calculated from echocardiographic and hemodynamic data. RESULTS: Although plasma BNP had a significant correlation (r2 = 0.296 [p < 0.001]) with left ventricular end-diastolic pressure (EDP) as previously reported, the correlation between plasma BNP and end-diastolic wall stress (EDWS) (r2 = 0.887 [p < 0.001]) was more robust. In a subanalysis of 62 patients with DHF, a similar result was obtained (r2 = 0.143 for EDP and r2 = 0.704 for EDWS). In a comparison between SHF and DHF, the BNP level was significantly higher in SHF (p < 0.001). Although EDP did not show any difference, EDWS was significantly higher in SHF than in DHF (p < 0.001). CONCLUSIONS: The present study shows that plasma BNP levels reflect left ventricular EDWS more than any other parameter previously reported, not only in patients with SHF, but also in patients with DHF. The relationship of left ventricular EDWS to plasma BNP may provide a better fundamental understanding of the interindividual heterogeneity in BNP levels and their clinical utility in the diagnosis and management of HF.