For citations:

Vaisberg A.R., Fomin I.V., Polyakov D.S., Omarova Yu.V. Contribution of the COVID-19 pandemic to the prognosis of patients with class III-IV heart failure. Russian Journal of Cardiology. 2022;27(3):4842. (In Russ.) https://doi.org/10.15829/1560-4071-2022-4842