Moscow city. The building of the Sklifosovsky Research Institute for Emergency Medicine. Director of the Institute M. M. Tarasov and head of the organ transplant laboratory V. P. Demikhov discuss the scheme of heart transplant in a dog. Doctors prepare dogs for surgery. V.P.Demikhov makes an operation. Present: M. M. Tarasov, assistants. Dogs run across the field, play with each other. A nurse with dogs on a leash walks down the corridor of the institute. VP Demikhov puts the dog on the couch, listens to her with a phonendoscope. The dog's heart murmurs are recorded on a tape recorder. Removing the cardiogram. V.P.Demikhov studies the dog's cardiogram and feeds it.