Self-venting balloon dilatation catheter and method

Abstract

Self-venting balloon dilatation catheter having a flexible tubular member with first and second lumens extending therethrough. An inflatable balloon is carried by the distal extremity of the tubular member in such a manner so that the first lumen extends through the balloon and is out of communication with the interior of the balloon and the second lumen is in communication with the interior of the balloon. A venting device is disposed between the balloon and the tubular member for venting air from the interior of the balloon but inhibiting the escape of liquid from the balloon.

What is claimed is: 
     
       1. In a self-venting balloon dilatation catheter, a flexible tubular member having first and second lumens extending therethrough, an inflatable balloon carried by the distal extremity of the tubular member in such a manner so that the first lumen extends through the balloon and is out of communication with .[.that.]. .Iadd.the .Iaddend.the interior of the balloon and the second lumen is in communication with the .[.distal extremity.]. interior of the balloon and .[.means disposed between the balloon and tubular member.]. .Iadd.a passageway having a transverse cross-sectional dimension less than about 0.001 inch extending from the interior of the balloon to ambient .Iaddend.for venting air from the interior of the balloon but inhibiting the escape of liquid from the balloon. 
     
     
       2. A dilatation catheter as in claim 1 wherein said means is disposed between the balloon and a tubular member for venting air comprised of a flow passage having a diameter of less than approximately 0.001 inch. 
     
     
       3. A dilatation catheter as in claim 2 wherein said means is disposed between the balloon and the tubular member includes hydrophobic material. 
     
     
       4. A dilatation catheter as in claim 1 wherein said tubular member is comprised of a first tubular element having the first lumen extending therethrough, a second tubular element coaxially disposed over said first tubular element and forming the second lumen extending between the first and second tubular members and wherein the expandable balloon is carried by the second tubular element and has its interior in communication with the second lumen between the first and second tubular elements. 
     
     
       5. In a self-venting balloon dilatation catheter, a first tubular element having a lumen extending therethrough, a second tubular element coaxially disposed over said first tubular element and forming a lumen extending between the first and second tubular members, an expandable balloon carried by the second tubular element and having its interior in communication with the lumen between the first and second tubular elements and means disposed between the distal extremities of the first and second tubular elements for venting air from the interior of the balloon but inhibiting escape of a liquid from the balloon. 
     
     
       6. A dilatation catheter as in claim 5 wherein said means disposed between the distal extremities of the first and second tubular elements for venting air comprises a flow passage having a diameter less than approximately 0.001 inches. 
     
     
       7. A dilatation catheter as in claim 6 wherein said means disposed between the distal extremities of the first and second tubular elements includes hydrophobic material. 
     
     
       8. A balloon dilatation catheter as in claim 5 wherein said means disposed between the distal extremities of the first and second tubular elements for venting air includes members disposed between the first and second tubular elements permitting the escape of air from the interior of the balloon but inhibiting the escape of liquids from the balloon. 
     
     
       9. A dilatation catheter as in claim 5 wherein said first and second tubular elements are formed of thermoplastic materials. 
     
     
       10. A dilatation catheter as in claim 9 wherein the distal extremities of the first and second tubular elements are sealed by a heat shrink seal. .Iadd. 
     
     
       11.  A self-venting vascular comprising: a) a flexible tubular member having at least one inner lumen extending therethrough to an interior portion of the catheter with means to receive liquid under pressure;   b) a venting means with a flow restrictive passageway having a transverse cross-sectional dimension less than about 0.001 inch extending from the interior portion of the catheter to ambient which allows air but no substantial amount of liquid to pass therethrough while a pressure in excess of 100 psi is maintained in the interior of the catheter. .Iaddend. .Iadd.12. The self-venting catheter of claim 11 wherein the flow restrictive passageway of the venting means has circular transverse cross-sectional shape with a diameter of less than about 0.001 inch.   
     
     
        .Iaddend. .Iadd.13.  The self-venting catheter of claim 11 wherein the flow restrictive passageway of the venting means includes braided fibers. .Iaddend. .Iadd.14. The self-venting catheter of claim 11 wherein the flow restrictive passageway of the venting means includes hydrophobic filter material. .Iaddend. .Iadd.15. The self-venting catheter of claim 11 wherein the flow restrictive passageway of the venting means will allow no substantial amounts of inflating liquid to pass therethrough at pressures in excess of 100 psi. .Iaddend. .Iadd.16. In a balloon dilatation catheter comprising an elongated tubular member with an inflatable balloon on the distal portion thereof and with an inner lumen extending therein which is in fluid communication with the interior of the balloon and which directs inflating liquid therein, the improvement comprising an air venting means which includes at least one flow restrictive passageway having a transverse cross-sectional dimension less than about 0.001 inch extending between the balloon interior and ambient which allows air but no substantial amounts of inflating liquid to pass therethrough while a pressure in excess of 100 psi is maintained in the balloon interior. .Iaddend. .Iadd.17. The balloon dilatation catheter of claim 16 wherein the flow restrictive passageway has a circular transverse shape with a 
     
     
        diameter less than about 0.001 inch. .Iaddend. .Iadd.18.  The balloon dilatation catheter of claim 16 wherein the flow restrictive passageway contains braided fibers. .Iaddend. .Iadd.19. The balloon dilatation catheter of claim 16 wherein the flow restrictive passageway contains hydrophobic filter material. .Iaddend. .Iadd.20. The balloon dilatation catheter of claim 16 wherein a plurality of flow restrictive passageways are provided. .Iaddend. .Iadd.21. The balloon dilatation catheter of claim 16 wherein the flow restrictive passageway will allow no substantial amounts of inflating liquid to pass therethrough at liquid pressures in 
     
     
        excess of 100 psi. .Iaddend. .Iadd.22.  The balloon dilatation catheter of claim 16 wherein the flow restrictive passageway extends in a distal direction from the interior of the balloon. .Iaddend. .Iadd.23. The balloon dilatation catheter of claim 16 wherein the balloon has a distal end which is sealingly bonded to an inner member. .Iaddend. .Iadd.24. The balloon dilatation catheter of claim 23 wherein the flow restrictive passageway of the venting means extends from the interior of the balloon to ambient in a distal direction between the distal end of the balloon and the inner member. .Iaddend.