For citations:

Soldatova A.M., Kuznetsov V.A., Bogdanova D.S., Benzineb F.T. The incidence of frailty and its relationship with long-term survival in patients with heart failure and implanted cardiac resynchronization therapy devices. Russian Journal of Cardiology. 2020;25(8):3685. (In Russ.) https://doi.org/10.15829/1560-4071-2020-3685