Catheter guide wire with short spring tip and method of using the same

Abstract

Guide wire and method for insertion and use of a catheter. The guide wire has a shaft of substantially smaller diameter than the luminal opening, with a flexible coil at one end of the shaft. The guide wire is inserted into the cardiovascular system, and the catheter is advanced along the guide wire to the desired position, with the flexible coil outside the distal end of the catheter. An annular passageway is formed between the shaft and the wall of the luminal opening, and fluids are passed through this passageway while the guide wire is within the catheter. A marker of radio opaque material is provided at the distal end of the guide wire so that the position of the wire can be accurately determined even though the wire itself may be too small to be visible with a fluoroscope.

We claim: .[.1. In a guide wire for use in the placement of a catheter in the cardiovascular system, an elongated shaft of relatively rigid material having proximal and distal ends and a cross-sectional area substantially smaller than the luminal opening in the catheter, a relatively flexible helical coil having proximal and distal ends, said coil having an outer diameter slightly smaller than the diameter of the luminal opening and a length substantially less than the length of the shaft, the distal end portion of the shaft extending into the coil but terminating short of the distal end of the coil, the portion of the shaft extending into the coil being tapered to provide a gradual transition in flexibility of the shaft, means for bonding the proximal end of the coil to the shaft and a flexible safety wire disposed interiorally of the coil and having one end bonded to the distal extremity of the shaft and having the other end bonded to the 
     
        distal extremity of the coil..]. 2. A guide wire as in claim .[.1.]. .Iadd.17 .Iaddend.wherein the safety wire is formed as a flat ribbon 
     
     
        having a generally rectangular cross section. 3. A guide wire as in claim .[.1.]. .Iadd.17 .Iaddend.together with a relatively smooth rounded tip 
     
     
        disposed at the distal extremity of the coil. 4. A guide wire as in claim .[.1.]. .Iadd.17 .Iaddend.together with a radio opaque marker formed of radio opaque material carried by the shaft adjacent the distal end of the 
     
     
        shaft. 5. A guide wire as in claim 4 wherein the radio opaque material has 
     
     
        a density of at least 13 gm/cm 3 . 6. A guide wire a in claim 5 wherein the radio opaque material includes an element selected from the group consisting of gold, tantalumm, tungsten, platinum, iridium, rhenium and 
     
     
        alloys thereof. 7. A guide wire as in claim 6 wherein the radio opaque material comprises an alloy containing on the order of 80% gold, 12% 
     
     
        siliver, and 8% copper and zinc. 8. A guide wire as in claim .[.1.]. .Iadd.17 .Iaddend.wherein the helical coil is formed of a radio opaque 
     
     
        material. 9. .[.In apparatus.]. .Iadd.A dilatation catheter assembly .Iaddend.for use in the cardiovascular system.[.,.]. .Iadd.of a patient comprising .Iaddend.an elongated, relatively flexible catheter having a wall defining an axially extending .[.luminal opening.]. .Iadd.lumen .Iaddend.and a guide wire extending through the .[.luminal opening.]. .Iadd.lumen .Iaddend.and having a .[.cross-sectional area.]. .Iadd.diameter .Iaddend.substantially smaller than the .[.luminal opening.]. .Iadd.lumen .Iaddend.so that fluids can pass freely between the guide wire and the wall defining the .[.luminal opening.]. .Iadd.lumen.Iaddend., said guide wire comprising an elongated shaft of relatively rigid material having proximal and distal ends and a .[.cross-sectional area.]. .Iadd.diameter .Iaddend.substantially smaller than .[.the luminal opening in the catheter.]. .Iadd.0.02 inch.Iaddend., a relatively flexible helical coil having proximal and distal ends, said coil having an outer diameter slightly smaller than .[.the diameter of the luminal opening.]. .Iadd.0.02 inch and substantially larger than the diameter of the shaft .Iaddend.and a length substantially less than the length of the shaft, the distal end portion of the shaft extending into the helical coil but terminating short of the distal end of the coil, the portion of the shaft extending into the coil being tapered to provide a gradual transition in flexibility of the shaft, means for bonding the proximal end of the coil to the shaft and a flexible safety wire disposed interiorally of the coil and having one end bonded to the distal extremity of the shaft and having the other end bonded to the distal extremity of 
     
     
        the coil. 10. Apparatus as in claim 9 wherein the safety wire is formed as 
     
     
        a flat ribbon having a generally rectangular cross section. 11. Apparatus as in claim 9 wherein the luminal opening has a diameter on the order of 0.020 inch, the guide wire shaft has a diameter on the order of 0.008 
     
     
        inch, and the helical coil has a diameter on the order of 0.018 inch. 12. Apparatus as in claim 9 together with a radio opaque marker formed of radio opaque material carried by the shaft adjacent the distal end of the 
     
     
        shaft. 13. Apparatus as in claim 12 wherein the radio opaque material has 
     
     
        a density of at least 13 gm/cm 3 . 14. Apparatus as in claim 12 wherein the radio opaque material includes an element selected from the group consisting of gold, tantalum, tungsten, platinum, iridium, rhenium and 
     
     
        alloys thereof. 15. Apparatus as in claim 12 wherein the radio opaque material comprises an alloy containing on the order of 80% gold, 12% 
     
     
        silver, and 8% copper and zinc. 16. The apparatus of claim 12 wherein the 
     
     
        helical coil is formed of a radio opaque material. .Iadd.17.  A guide wire for use in the placement of a catheter having an inner lumen extending therein into a patient's cardiovascular system comprising: a) an elongated shaft of relatively rigid material having proximal and distal ends and a diameter substantially smaller than the diameter of the inner lumen;   b) a relatively flexible helical coil having proximal and distal ends and an outer diameter slightly smaller than 0.02 inch and substantially larger than the diameter of the shaft and a length substantially less than the length of the shaft, the distal end portion of the shaft being tapered to provide a gradual transition in flexibility of the shaft and the tapered portion and extending into the coil but terminating short of the distal end of the coil;   c) means for bonding the proximal end of the coil to the shaft; and   d) a flexible safety wire disposed interiorly of the coil and having one end bonded to the distal extremity of the shaft and having the other end bonded to the distal extremity of the coil. .Iaddend.