The issue of blood pressure levels is practically very important in patients with chronic heart failure (CHF). As is known, combination therapy for the latter implies the use of several groups of hemodynamically relevant agents; diuretics are an important component of CHF therapy. However, diuretics are the most unstudied medications in the treatment of patients with CHF in the context of evidence-based medicine. On the one hand, their efficacy and necessity for the treatment of patients with cardiac decompensation are beyond question and, on the other, even if you want, placebo-controlled trials using diuretics look difficult to perform.