Relationship between N-terminal pro-B type natriuretic peptide and extensive echocardiographic parameters in mild to...

The N-terminal pro-B type natriuretic peptide levels (NT pro-BNP) are increased in cases of volume or pressure overload.

To examine NT pro-BNP levels and enclose whether any relationship is present between the levels of NT pro-BNP and extensive echocardiographic parameters in asymptomatic patients with mild to moderate aortic stenosis (AS).

A cross-sectional study about the NT pro-BNP levels was conducted in 37 asymptomatic AS patients and compared with 40 controls.

Patients < 70 years old with mild to moderate AS with a peak transaortic gradient > 20 mm Hg in transthoracic echocardiogram were included in our study. Extensive echocardiographic parameters and NT pro-BNP levels were obtained from these patients and these indices were compared with the control population selected from the patients who had similar clinical characteristics with the AS patients.

NT-proBNP values were found to be distribution free. Spearman correlation coefficient was used for correlation analysis. Mean values were compared by the Kruskal-Wallis test.

The NT pro-BNP levels were increased in patients with AS (median; interquartiles range: 686 [449-855] pg/mL vs. 140 [116-150] pg/mL, P < 0.001). Among patients with AS, when correlation analysis was performed mean transaortic gradient, aortic valve area index, myocardial performance index, E(m)/A(m) ratio, left-ventricular mass index (LVMI) and E/E(m) ratio had correlations (r=0.38, P = 0.026; r=-0.46, P =0.008; r=0.19, P =0,049; r=-0.22, P =0.04, r=0.49, P =0.003 and r=0.53, P <0.001 respectively) with plasma NT pro-BNP levels. The LVMI (r = 0.49, P = 0.003) and E/E(m) ratio (r = 0.53 P < 0.001) have the strongest correlations when compared to other parameters.

Plasma NT pro-BNP levels are increased in even asymptomatic patients with AS and correlated with several echocardiographic parameters related to severity of AS and degree of diastolic dysfunction. As a result, NT pro-BNP levels may be used in the follow-up of asymptomatic patients having mild to moderate AS.