B-Type Natriuretic Peptide is a substance secreted from the ventricles or lower chambers of the heart in response to changes in pressure that occur when heart failure develops and worsens. The levels of B-type natriuretic peptide are elevated in patients with left ventricular dysfunction. BNP levels correlate with both the severity of symptoms and the prognosis in congestive heart failure. B-type natriuretic peptide is a neurohormone secreted from cardiac ventricles in response to ventricular strain. B-type natriuretic peptide is a predictor of short- and medium-term prognosis across the spectrum of acute coronary syndromes (ACS).