Clinical correlates of very high brain natriuretic peptide levels in hospitalized patients

While low brain natriuretic peptide (BNP) values have been shown to improve diagnostic accuracy by excluding congestive heart failure in acute dyspnea, the meaning of excessively elevated BNP is not clear. This is a retrospective analysis of clinical, echocardiographic, and laboratory data in patients with BNP values <2500 ng/L. Sixty-seven patients (36 men) with a median age of 79 years were included. The median BNP level was 3118 ng/L (2506-5000 ng/L). Forty-six percent of the patients had no dyspnea or New York Heart Association class II dyspnea. Most patients had impaired renal function. BNP value did not correlate with ejection fraction (r=0.2; P=.15) and weakly correlated with left ventricular end-diastolic diameter index (r=0.26; P=.02). Very high BNP values only poorly correlated with dyspnea and traditional echocardiographic markers of congestive heart failure. The clinical usefulness of very high BNP values is questionable and needs evaluation in a prospective trial.