PLASMA BRAIN NATRIURETIC PEPTIDE CONCENTRATIONS IN PATIENTS WITH CHRONIC MITRAL REGURGITATION

Background and aims of the study: Patients with chronic mitral regurgi tation (MR) are often referred for surgery only after irreversible lef t ventricular (LV) dysfunction has developed. Our aim was to determine whether plasma brain natriuretic peptide (BNP) concentrations could s erve as a marker for early LV dysfunction in this condition. Methods: Twenty-two patients with isolated chronic MR and echocardiographic evi dence of at least moderate regurgitation were studied. Results: Plasma BNP concentrations were significantly higher in patients than in norm al volunteers (20.85 +/- 16.9 versus 3.37 +/- 0.9 pmol/l; p = 0.007). Concentrations increased with increasing severity of symptoms and were highest in those in NYHA class IV, but did not correlate with LV dime nsions, fractional shortening or left atrial size. Of note, two asympt omatic patients with high BNP concentrations were referred for surgery within the 12-month follow up period due to symptom progression. Conc lusions: Plasma BNP concentrations are elevated in most patients with isolated chronic MR, including those who are asymptomatic with normal LV dimensions. The significance of these findings is uncertain, but th ey suggest that changes in ventricular physiology occur early in the d isease process and before they can be detected echocardiographically. Longitudinal studies are required to determine if patients with high B NP levels have an adverse prognosis and if this can be altered by earl ier surgical intervention.