Peptide Helps Diagnose Source of Chronic Dyspnea
Its presence indicates cardiac but not pulmonary dysfunction
WEDNESDAY, Oct. 17 (HealthDay News) -- In patients with dyspnea, plasma levels of pro-B-type natriuretic peptide (proBNP) are unaffected by pulmonary dysfunction, but are elevated when there is left ventricular dilatation, hypertrophy, systolic dysfunction or diastolic dysfunction, according to research published in the Oct. 23 issue of the Journal of the American College of Cardiology.
Rasmus Mogelvang, M.D., of the University of Copenhagen in Denmark, and colleagues conducted a study of 2,929 participants in the Copenhagen City Heart Study, of whom 959 reported dyspnea. Those that did had a mean 17.8 pmol/L concentration of proBNP, compared with 10.6 pmol/L for the patients with no reported dyspnea.
Among the dyspnea group, left ventricular hypertrophy and/or systolic dysfunction was associated with a 2.6-times higher level of proBNP, but there was no increase associated with pulmonary dysfunction. In dyspneic patients, left ventricular and diastolic dysfunction could be ruled out if concentrations of proBNP were less than half of that was expected, the authors write.
"The crucial point is that plasma proBNP is unaffected by pulmonary function. Thus, if pulmonary dysfunction is suspected, then pulmonary status should be pursued, regardless of plasma proBNP level," the authors write. "In contrast, if plasma proBNP is higher than expected in relation to age and gender, then cardiac dysfunction is likely and cardiac status should be evaluated regardless of the pulmonary status."