Elevated Plasma Marinobufagenin, An Endogenous Cardiotonic Steroid, Is Associated With Right Ventricular Dysfunction and Nitrative Stress in Heart Failure.

Background: Plasma levels of cardiotonic steroids are elevated in volume-expanded states, such as chronic kidney disease, but the role of these natriuretic hormones in subjects with heart failure (HF) is unclear. We sought to determine the prognostic role of the cardiotonic steroids marinobufagenin (MBG) in HF, particularly in relation to long-term outcomes.

Methods And Results: We first measured plasma MBG levels and performed comprehensive clinical, laboratory, and echocardiographic assessment in 245 patients with HF.