The diagnosis of acute congestive heart failure: role of BNP measurements.

For the acutely ill patient presenting to the emergency department with dyspnea, an incorrect diagnosis could place the patient at risk for both morbidity and mortality. The stimulus for BNP release is a change in left-ventricular wall stretch and volume overload. A rapid whole blood BNP assay has recently approved by the FDA (Triage BNP Test, Biosite Inc, San Diego CA) that allows one to quickly evaluate the dyspneic patient, and set the stage for the recently completed multinational Breathing Not Properly (BNP) study. The Breathing Not Properly Multinational Study was a seven center, prospective study of 1586 patients who presented to the emergency department with acute dyspnea and had BNP measured with a point-of-care assay upon arrival. BNP was accurate in making the diagnosis of CHF and correlated to severity of disease. It could have reduced clinical indecision by 74%. Algorithms are being developed for use in the emergency room which takes into account other illnesses that might raise BNP levels. BNP levels should be extremely important in ruling out and diagnosing decompensated CHF, as long as baseline "euvolemic" BNP values are known. Finally, it is possible that use of BNP levels might not only be helpful in assessing whether or not a dyspneic patient has heart failure, but it my turn out to be useful in making both triage and management decisions.