Effects of levosimendan versus dobutamine on left atrial function in decompensated heart failure

Abstract

Although the effects of levosimendan on the left ventricle (LV) have been studied, its effect on left atrial (LA) function is poorly understood, despite its key role in optimizing LV function. To compare the effects of levosimendan and dobutamine on LA and LV function in patients with decompensated heart failure (DHF). Seventy-four patients (mean [+/- SD] age 64+/-10 years) with DHF and an LV ejection fraction of 35% or lower were randomly assigned to receive levosimendan (n=37) or dobutamine (n=37). LA active emptying fraction, LA passive emptying fraction (PEF) and the ratio of mitral inflow early diastolic velocity to annulus velocity (E/e) were evaluated with pulsed wave and tissue Doppler imaging along with plasma B-type natriuretic peptide (BNP) level measurements before and after drug infusion. The ejection fraction was significantly increased in both groups. The levosimendan group had a greater decrease in BNP and a greater increase in active emptying fraction at 24 h compared with the dobutamine group. The PEF, E/e and deceleration time of the E wave were significantly improved in the levosimendan group, but not in the dobutamine group. Levosimendan- induced percentage change of BNP was significantly correlated with the percentage change of E/e and PEF (r=0.48 [P<0.005] and r=-0.38 [P<0.05], respectively). In patients with DHF, levosimendan and dobutamine both improve LV systolic function. However, levosimendan also improves LV diastolic function and LA performance in parallel with a greater improvement in neurohormonal activation compared with dobutamine.