Abstract
Background We investigated whether the increase of plasma natriuretic peptides (NPs) in atrial fibrillation (AF) is independent of the effect of AF on the left atrial (LA) hemodynamics. Methods Hemodynamically stable patients scheduled for AF ablation underwent assessment of B-type natriuretic peptide (BNP) and mid-regional pro-atrial natriuretic peptide (MR-proANP), echocardiography, and direct measurement of left atrial (LA) pressure.
Concentrations of the NPs were compared between patients in AF (n=31) and controls in sinus rhythm (SR; n=31) who were matched for age, gender, heart rate, left ventricular ejection fraction, LA volume index, and directly measured mean LA pressure. Eighteen patients underwent serial measurement of NPs and LA pressure during native SR and after 20min of pacing-induced AF.
Results Compared to the patients in SR, the patients in AF had 2.6 times higher unadjusted BNP [median (inter-quartile range), 101 (63, 129) vs. 38 (26, 79) ng/L] and two times higher unadjusted MR-proANP [183 (140, 230) vs. 91 (67, 135) pmol/L; both p0.3). Both NPs increased significantly during induced AF [adjusted median (IQR) relative change, BNP: 27 (22; 40)%, MR-proANP: 75 (64; 99)%, both p<0.001] without a significant change in the LA pressure.
Conclusions The increase of NPs in AF was independent of its effect on the LA hemodynamics.