A cryotherapeutic device having an integral multi-helical balloon section and methods of making the same. A method of forming the cryotherapeutic device can include forming an extruded integral shaft having first and second substantially parallel lumens. The method can further include twisting a distal section of the shaft such that the first and second lumens form intertwined helical portions. The first and second helical portions can be plastically enlarged to form an inflatable body configured to deliver therapeutically effective cryogenic cooling to a treatment site.