Wire for inserting into biological duct

A wire for insertion into intravital tracts comprising:

• a principal wire to be inserted into an intravital tract comprised of flexible filaments having at a tip a capture filter comprising:
• a filter body formed into a mesh state by knitting ends of additional flexible filaments and forming the mesh state into a concave shape with a closed farther end and an opened nearer end;
• and
• support wires formed by dividing the flexible filaments at the opened nearer end of the filter body into a plurality of sets, each set of flexible filaments twined together, wherein ends of the plurality of sets of filaments are spliced to the principal wire,
• wherein each of the support wires extends radially in the direction toward the closed farther end and in the direction of an outer diameter, and the concave shape is configured to face the support wires and inclined toward an outer circumference of the filter body in a lying posture relative to the blood current, a mesh size of the mesh state decreases toward a central part of the concave shape at the farther closed end, and wherein
• the filaments constituting the support wires and filter body are shape-memory alloy and have an elastic force to form the shape.