The determinants of plasma brain natriuretic peptide level in severe aortic valve stenosis patients undergoing transcatheter aortic valve implantation

Abstract

BackgroundBrain or B-type natriuretic peptide (BNP) is an objective marker to diagnose the presence of heart failure (HF) and assess its severity. However, the determinants of serum BNP level in elderly patients with severe aortic valve stenosis (AS) referred for transcatheter aortic valve implantation (TAVI) have not been well investigated. MethodsWe prospectively studied 106 AS patients who underwent TAVI. Cardiac catheterization, transesophageal echocardiography, and blood collection for plasma BNP level measurements were performed simultaneously just before the TAVI procedures. ResultsNinety-nine patients (83.9±5.0 years, 33% male) were studied. The natural logarithm of BNP (lnBNP) level was 5.4±0.9 pg/mL. Significant correlations with lnBNP level were observed in: 1) the history of syncope, prior HF medication, and New York Heart Association class III or IV (R=0.255, p=0.011) (R=0.210, p=0.037) (R=0.402, p<0.001), 2) albumin and hemoglobin level (R=-0.289, p=0.004) (R=0.263, p=0.009), 3) Left ventricular (LV) ejection fraction and global longitudinal strain (LVGLS) (R=-0.338, p<0.001) (R=0.447, p<0.001), 4) LV end-diastolic volume index (EDVI), LV mass index, and left atrial volume index (R=0.280, p=0.005) (R=0.366, p<0.001) (R=0.337, p<0.001), 5) the catheter-measured pressure gradient across the aortic valve (AVPG) (R=0.365, p<0.001). Note that LV wall stress was not significantly correlated with lnBNP level. LVGLS, AVPG, hemoglobin level, and LVEDVI were independently correlated with ln BNP level (R=0.652, LVGLS; β=0.395, p<0.006, AVPG; β=0.291, p=0.001, hemoglobin level; β=-0.216, p=0.011, and LVEDVI; β=0.203, p=0.016, respectively). ConclusionsIn severe AS patients candidate for TAVI, multiple factors, including the severities of AS and HF conditions and subclinical LV dysfunction determined by LVGLS affects plasma BNP level.