Found this (bad quality) video and after some research a www.time.com/time/magazine/article/0,9171,891156,00.html article from January 17, 1955 that sheds some light on it:Transplanted HeadIn the Soviet Ogonek, Georgi Blok describes a sensational exhibit at a recent meeting of the Moscow Surgical Society. On the platform close to the guests of honor stood a large white dog, wagging its tail. From one side of its neck protruded the head of a small brown puppy. As the surgeons watched, the puppy's head bit the nearest white ear. The white head snarled.The two-headed dog, no freak of nature, was the latest product of Surgeon en.wikipedia.org/wiki/Vladimir_Demikhov , chief of the organ-transplanting laboratory of the Soviet Academy of Medical Sciences. Dr. Demikhov, says Blok, started in a small way by replacing the hearts of dogs with artificial blood pumps. Next, he planted a second heart in a dog's chest, removing part of a lung to make room for it. The extra heart continued its own rhythm, beating independently of the original heart.After repeating this operation many times, Dr. Demikhov could keep two-hearted dogs alive for as long as 2½ months. Sometimes the original heart stopped beating first. Then the second heart carried the burden until it failed too.Encouraged by his successes, Dr. Demikhov tried the reverse operation. He removed most of the body of a small puppy and grafted the head and forelegs to the neck of an adult dog. The big dog's heart, as Blok tells the story, pumped blood enough for both heads. When the multiple dog regained consciousness after the operation, the puppy's head woke up and yawned. The big head gave it a puzzled look and tried at first to shake it off.The puppy's head kept its own personality. Though handicapped by having almost no body of its own, it was as playful as any other puppy. It growled and snarled with mock fierceness or licked the hand that caressed it. The host-dog was bored by all this, but soon became reconciled to the unaccountable puppy that had sprouted out of its neck. When it got thirsty, the puppy got thirsty and lapped milk eagerly. When the laboratory grew hot, both host-dog and puppy put out their tongues and panted to cool off. After six days of life together, both heads and the common body died.Dr. Demikhov's two-headed dog, Blok points out, was not a mere stunt. It was part of a long-range attempt to learn how damaged organs can be replaced, or how their functions can be performed by mechanical substitutes.