| 摘要 |
A system and method for forming a three-dimensional wireform for heart valves from a two-dimensional starting shape. The wireform has multiple arcuate cusps and oppositely directed commissure tips therebetween, the cusps and commissure tips being oriented generally in a tube about an axis. The two-dimensional wire has three cusps and two commissure tips, with two free ends having bent segments. The wireforming system and process holds the commissure tips, or one commissure tip and one bent segment, and forms the cusp therebetween. The wire is held by two axially-parallel mandrels and cooperating clamps which axially rotate and move toward one another. A forming surface on each mandrel bends one half of the cusp, the forming surfaces being mirror images of one another. The forming surface has a complex curvature specifically designed to shape a particular size of wireform into a desired final three-dimensional shape. After bending all the cusps, the free ends of the wire are joined, such as with a tubular crimp, and the wireform assembled into a tissue-type heart valve. |
