NPPB and heart failure: Clinically, the extent of BNP elevation often corresponds with the symptomatology of heart failure exacerbation, as cardiogenic volume or pressure overload contributes to increased pulmonary venous pressure and pulmonary capillary pressure, which shifts fluid into interstitial spaces of alveoli, ultimately presenting as shortness of breath, orthopnea, and paroxysmal nocturnal dyspnea in patients.