Abstract
The cardiorenal syndrome has recently been defined as "disorders of the heart and kidney whereby acute or chronic dysfunction in one organ may induce acute or chronic dysfunction of the other." The syndrome is extremely common and independently associated with poor clinical outcomes. However, no pharmacological therapy has been shown to improve its outcomes. Unfortunately, the mechanisms that initiate the development of renal dysfunction in heart failure are still debated. This review tries to clarify some of the misunderstanding regarding the principle hemodynamic factors that drive the kidneys to retain salt and water.