Cardio-renal anemia syndrome.

Heart failure (HF) is a systemic disease that also involves organs and tissues other than the heart and the vasculature. Between 25 and 50% of patients with HF are also affected by some degree of kidney disease. Anemia may be present in patients with HF, particularly if the kidney is also affected. Anemia is observed in about 20% of patients with ambulatory HF, but its prevalence may increase to 60% or more in patients with advanced disease or significant co-morbidities. Cardio-renal anemia syndrome (CRAS) represents a pathological triangle in which the primary failing organ is either the heart or the kidney, and the dysfunction of one leads to dysfunction of the other. Mortality rates increase with only anemia or kidney disease being present in patients with HF. The full clinical picture of CRAS is present in about 20% of all patients hospitalized for HF. In such patients, a steep increase in mortality rates has been observed. This article describes the suggested classification systems of CRAS, its clinical significance, and potential therapeutic avenues.