Pathological interplay between the heart and kidneys is widely encountered in heart
failure (HF) and is linked to worse prognosis and quality of life. Inotropes, along
with diuretics and vasodilators, are a core medical response to HF but decompensated
patients who need inotropic support often present with an acute worsening of renal
function. The impact of inotropes on renal function is thus potentially an important
influence on the choice of therapy. There is currently relatively little objective
data available to guide the selection of inotrope therapy but recent direct observations
on the effects of levosimendan and milrinone on glomerular filtration favour levosimendan.
Other lines of evidence indicate that in acute decompensated HF levosimendan has an
immediate renoprotective effect by increasing renal blood flow through preferential
vasodilation of the renal afferent arterioles and increases in glomerular filtration
rate: potential for renal medullary ischaemia is avoided by an offsetting increase
in renal oxygen delivery. These indications of a putative reno-protective action of
levosimendan support the view that this calcium-sensitizing inodilator may be preferable
to dobutamine or other adrenergic inotropes in some settings by virtue of its renal
effects. Additional large studies will be required, however, to clarify the renal
effects of levosimendan in this and other relevant clinical situations, such as cardiac
surgery.
