[Cardio-renal axis : Relationship of heart failure and renal insufficiency as comorbidities].

Heart failure and kidney dysfunction are common comorbidities with overlapping and synergizing mechanisms. Coincidence of both pathologies aggravates disease progression rates, symptoms, and outcomes. The treatment of patients with advanced renal insufficiency is faced with limited evidence for therapies that are standard of care in patients with normal and moderate kidney failure, frequent deterioration of kidney function during therapy, and onset of hyperkalemia, which pose challenges for clinical care, requiring intensified physician-patient contacts. A special challenge is the so-called diuretic resistance, which may require extracorporeal drainage.