Abstract: In a medical guide wire 1, a rear half of a leading bulge portion (ellipsoidal helical spring) 5 forms a truncated cone shaped front catheter engagement portion 8. An inner wall of a balloon catheter 2 forms a flared end portion 2A which absorbably fits into the front catheter engagement portion 8 due to the physical adhesion so to provisionally connect the balloon catheter 2 to the front catheter engagement portion 8. The medical guide wire 1 and the balloon catheter 2 are inserted into the blood vessel with one single step procedure when the medical guide wire 1 is introduced into the blood vessel to place the balloon portion 10 at the stricture blood vessel area (P).

Abstract: With an introducing catheter (A) accommodated by a diagnostic-therapeutic catheter (B), the necessity of a sheath is eliminated to render the diagnostic-therapeutic catheter (B) as large as the sheath. This enables a manipulator to fully treat a patient with the use of diagnostic-therapeutic catheter (E). With the elimination of the sheath, the diagnostic-therapeutic catheter (B) is directly inserted into tubular human organs (e.g., radial artery and brachial artery). Coaxially provided are inner and outer tubes 12, 13 with the diagnostic-therapeutic catheter (B) to have an annular space 14, at least a part of which forms a drug-releasable open end 15 exposed to a shaft portion 11. The outer tube 13 has a plurality of drug-releasable side holes 9 to release an anti-spasmodic drug toward a blood vessel through the drug-releasable open end 15.

Abstract: In a medical guide wire 1, a rear half of a leading bulge portion (ellipsoidal helical spring) 5 forms a truncated cone shaped front catheter engagement portion 8. An inner wall of a balloon catheter 2 forms a spiral groove 9. The spiral groove 9 fits into the front catheter engagement portion 8 to provisionally connect the balloon catheter 2 to the front catheter engagement portion 8. The medical guide wire 1 and the balloon catheter 2 are inserted into the blood vessel with one single step procedure when the medical guide wire 1 is introduced into the blood vessel to place the balloon portion 10 at the stricture blood vessel area (P) to cure the stricture blood vessel area (P).