The heart has a bezel (2) with orifices (6, 7) respectively contacting artificial right and left ventricles. A bezel (3) has orifices (8, 9) respectively connected to natural right and left atriums of a patient. The bezels are removably connected with each other to occupy an operating position in which the orifices (8, 9) are opposite to the orifices (6, 7). The orifices (8, 9) have individual suture collars (11) removably mounted on the orifices (8, 9) in a freely rotatable manner. Each collar has a central opening delimited by an edge extended by a ring in elastic material e.g. elastomer.
