| 摘要 |
This invention is a method of manufacturing a rotational atherectomy drive shaft (20) having an asymmetrical tissue removal section (28). One or more strands of wire are helically wound about an elongated mandrel having an enlarged diameter section (28) with a predetermined shape, thereby forming an elongated, flexible drive shaft (20) which has an enlarged diameter tissue removal section (28). A protion of the drive shaft (20), including the enlarged diameter tissue removal section (28) is placed into a first clamp, and given a first heat treatment to give the wire turns (31) of the enlarged diameter tissue removal section an initial set, thereby preserving the initial shape of the enlarged diameter tissue removal section (28) of the drive shaft (20) . The drive shaft (20) is then removed from the first clamp, and the mandrel (50) is dissolved. The enlarged diameter section (28) of the dri ve shaft (20) is then deformed to an asymmetrical shape by placing a portion of the drive shaft (20), including the enlarged diameter tissue removal section (28) into a second clamp. The clamped portion of the drive shaft (20) is then heat treated for a second time to gi ve wire turns (31) of the enlarged diameter tissue removal section (28) a new set, thereby preserving the asymmetrical shape of the enlarged diameter section (28). In its asymmetrical shape the enlarged diameter tissue removal section (28) 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 driveshaft.
|
