Renal failure in decompensated heart failure patients: Double trouble.

The association between cardiac and renal disease has been an area of growing interest in recent years. The interactions between these organs play an important role in control of blood pressure, renal sodium and water excretion, arterial perfusion and tissue oxygenation, and, most importantly, extracellular fluid balance, including intravascular volume. It is therefore not surprising that, when one organ becomes dysfunctional, the other may be affected as well. Heart failure (HF) interacts with renal disease via several pathophysiological pathways in both acute and chronic settings. The expression ‘cardiorenal syndrome’ has often been used in the last decade to define this interdependency of the kidneys and the heart, and as an umbrella term for worse outcome when the two organs fail simultaneously. A recent review of the pathophysiological pathways of this syndrome was recently published by Schefold et al. Although the concept of the cardiorenal syndrome is helpful when describing these heart-kidney interactions, it should be emphasized that the current definition of cardiorenal syndrome includes all forms of two-way connections and is not specific to HF.