Vascular anastomosis device and vascular anastomosis method

A vascular anastomosis device for anastomosing two blood vessels with different diameters, the device comprising

• a first ring with pins and a second ring with pins both made of a material which is deformable by an external force and allows the pins to stick thereinto;
• and
• an openable ring holder, which is made of a pair of components, detachably holds the first ring with pins and the second ring with pins, and has a means for deforming the rings with pins,
• wherein vascular anastomosis can be achieved in the following manner:
• the ring holder holding the rings is opened,
• an end portion of a large-diameter blood vessel is inserted through the first ring and the vascular wall is extended outward 90 degrees and impaled on the pins,
• an end portion of a small-diameter blood vessel is inserted through the second ring,
• an incision is made in a longitudinal direction from the end surface of the small-diameter blood vessel,
• the first ring and the second ring are deformed into a same elliptical shape by the means for deforming the rings so that the minor axis agrees with the diameter of the small-diameter blood vessel,
• the small-diameter blood vessel is elliptically opened and the vascular wall is extended outward 90 degrees and impaled on the pins, and
• the first ring and the second ring are joined together by allowing the pins provided on the ring in one component to stick into the ring in the other component to anastomose the large-diameter blood vessel and the small diameter blood vessel.