| 摘要 |
A method of manufacturing a rotational atherectomy drive shaft having an asymmetrical tissue removal section. One or more strands of wire are helically wound about an elongated mandrel having an enlarged diameter section with a predetermined shape, thereby forming an elongated, flexible drive shaft which has an enlarged diameter tissue removal section. A portion of the drive shaft, including the enlarged diameter tissue removal section, is placed into a first clamp and given a first heat treatment to give the wire turns of the enlarged diameter tissue removal section an initial set, thereby preserving the initial shape of the enlarged diameter tissue removal section of the drive shaft. The drive shaft is then removed from the first clamp and the mandrel is dissolved. The enlarged diameter section of the drive shaft is then deformed to an asymmetrical shape by placing a portion of the drive shaft, including the enlarged diameter tissue removal section, into a second clamp. The clamped portion of the drive shaft is then heat treated for a second time to give wire turns of the enlarged diameter tissue removal section a new set, thereby preserving the asymmetrical shape of the enlarged diameter section. In its asymmetrical shape the enlarged diameter tissue removal section has a longitudinally flat "side"-i.e., all wire turns of the tissue removal section may be connected by an imaginary straight line which throughout its length is parallel to the rotational axis of the drive shaft. |
