Unexpectedly Low Natriuretic Peptide Levels in Patients With Heart Failure

OBJECTIVES: We sought to determine the frequency of unexpectedly low natriuretic peptide (NP) levels in a clinical population. BACKGROUND: Higher NP concentrations are typically observed as a compensatory response to elevated cardiac wall stress. Under these conditions, low NP levels may be indicative of a “NP deficiency.” METHODS: We identified 3 clinical scenarios in which high B-type natriuretic peptide (BNP) levels would be expected: (A) hospitalization for heart failure (HF), (B) abnormal cardiac structure or function, or (C) abnormal hemodynamics. In Vanderbilt’s electronic health record, 47,970 adult patients had BNP measurements. A total of 13,613 patients had at least one of the 3 conditions (hospitalized HF, n=9,153; abnormal cardiac structure/function, n=7,041; abnormal hemodynamics, n=363). We quantified the frequency of low BNP levels. We performed whole exome sequencing of the NPPB gene in a subset of 9 patients. RESULTS: Very low BNP levels (