Cardiorenal Syndrome in Patients With Chronic Heart Failure as a Stage of the Cardiorenal Continuum (Part I): Definition, Classification, Pathogenesis, Diagnosis, Epidemiology

The combination of heart failure and renal failure is called cardiorenal syndrome. It is a stage of the cardiorenal continuum and, possibly, a small link of the cardiorenal-cerebral-metabolic axis. Despite the fact that the phrase “cardiorenal syndrome” and its five types have become a part of the medical lexicon, many aspects of this problem are still not clear. Cardiorenal syndrome can be diagnosed in 32-90.3% of patients with heart failure. Cardiorenal syndrome type 1 or 2 develops in most cases of heart failure: cardiorenal syndrome presents with the development ofchronic kidney disease in patients with chronic heart failure and acute kidney injury in patients with acute heart failure. Impaired renal function has an unfavorable prognostic value. It leads to an increase in the mortality of patients with heart failure. It is necessary to timely diagnose the presence of cardiorenal syndrome and take into account its presence when managing patients with heart failure. Further researches are needed on ways toprevent the development and prevent the progression of kidney damage in patients with heart failure, to which the efforts of the multidisciplinary team should be directed. The first part of this review examines the currently definition, classification, pathogenesis, epidemiology and prognosis of cardiorenal syndrome in patients with heart failure.