Introduction:

heart and kidney diseases frequently coexist. Cardiorenal syndrome is a complex entity in which primary cardiac dysfunction causes a kidney damage (types 1 and 2) and vice versa (types 3 and 4) or an effect of a systemic disease that affects both organs (type 5).

Objective:

to update the diagnosis and treatment of patients with cardiorenal syndrome.

Methods:

theoretical and empirical methods are used to carry out the analysis of updated knowledge on the subject. The existence of a cardiorenal syndrome that compromises both organs has been defined with bidirectional interaction. In its detection, clinical diagnosis is insufficient and requires biochemical markers; these tools, together with the measurement of urinary sodium, allow us to monitor therapeutic effectiveness. Another resource is ultrafiltration, according to complications.

Conclusions:

evidence-based treatment should be indicated to improve quality of life, reduce mortality, and delay the deterioration of renal and cardiac function in the long term; kidney transplantation should be considered in dialysis patients with severe ventricular dysfunction. Ideally, they should receive a combined transplant: heart and kidney, which is difficult; some patients undergoing exclusively a renal transplantation show a notable improvement in their ejection fraction and survival.