Guide wire for catheter

A guide wire for inserting a surrounding tubular catheter into the body of a warm-blooded animal such as a human being, comprising;

• an elongate body portion and an elongate distal end portion;
• coupled axially to said body portion;
• said body and distal end portions including:
• an inner core which includes a first inner core portion on said body portion's side and a second inner core portion on said distal end portion's side;
• an intermediate inner core portion between the inner core portion on the body portion's side and the inner core portion on the distal end portion's side, said intermediate inner core portion being progressively reduced in cross-section from the body portion toward the distal end portion;
• and
• whereby at least a portion of said distal end portion is smaller in cross-section than said body portion and
• a plastic coating covering said inner core as a whole;
• said body portion being comparatively high in rigidity and said distal and portion being substantially more flexible than said body portion;
• at least a portion of at least one of said first and second inner core portions being formed of a super-elastic metallic member having a solid cross-section and which includes an alloy selected from the group consisting of Ti-Ni alloy consisting essentially of 49-58 atom % Ni and the balance substantially Ti, Cu-Zn alloy consisting essentially of 38.5-41.5 wt % Zn and the balance substantially Cu, Cu-Zn-X, consisting essentially of 38.5-41.5 wt. % Zn, 1-10 wt, % X (X=Be, Si, Al or Ga) and the balance substantially Cu, and Ni-Al alloy consisting essentially of 36-38 atom % Al and the balance substantially Ni;
• the selected alloy forming said super-elastic metallic member being such that the temperature at which transformation to austenite is complete is at most about 10.degree. C.;
• and
• at least a portion of said second inner core portion on the distal end portion's side being smaller in cross-section than said first inner core portion on the body portion's side,
• wherein the guide wire is in a non-coiled monofilament form, and said metallic member exhibits pseudo-elasticity when inserted into the body of said warm-blooded animal.

A guide wire for inserting a surrounding tubular catheter into the body of a warm-blooded animal such as a human being, comprising;

• an elongate body portion and an elongate distal end portion;
• coupled axially to said body portion;
• said body and distal end portions including:
• an inner core which includes a first inner core portion on said body portion's side and a second inner core portion on said distal end portion's side;
• and
• a plastic coating covering said inner core as a whole;
• said body portion being comparatively high in rigidity and having a yield stress in the range of 10 to 80 kg/mm.sup.2 and said distal and portion being substantially more flexible than said body portion and having a yield stress less than the yield stress of said body portion and in the range of 10 to 80 kg/mm.sup.2 ;
• at least a portion of at least one of said first and second inner core portions being formed of a super-elastic metallic member having a solid cross-section and which includes an alloy selected from the group consisting of Ti-Ni alloy consisting essentially of 49-58 atom % Ni and the balance substantially Ti, Cu-Zn alloy consisting essentially of 38.5-41.5 wt % Zn and the balance substantially Cu, Cu-Zn-X, consisting essentially of 38.5-41.5 wt. % Zn, 1-10 wt, % X (X=Be, Si, Al or Ga) and the balance substantially Cu, and Ni-Al alloy consisting essentially of 36-38 atom % Al and the balance substantially Ni;
• the selected alloy forming said super-elastic metallic member being such that the temperature at which transformation to austenite is complete is at most about 10.degree. C.;
• at least a portion of said second inner core portion on the distal end portion's side being smaller in cross-section than said first inner core portion on the body portion's side,
• at least a portion of said distal end portion being smaller in cross-section than said body portion, and
• an intermediate inner core portion between the inner core portion on the body portion's side and the inner core portion on the distal end portion's side, said intermediate inner core portion being progressively reduced in cross-section from the body portion toward the distal end portion,
• wherein the guide wire is in a non-coiled monofilament form, and said metallic member exhibits pseudo-elasticity when inserted into the body of said warm-blooded animal.