Electrode assembly for temporary pacing and heart measurements

Abstract

An electrode assembly for use with a catheter, is made of a plurality of insulated wires. The wires are bound together in a bundle by fine insulated wire for almost their entire lengths. At one end of the bundle are free wire ends of different lengths on which are electrically conductive ferrules. The ferrules are spaced apart axially when aligned with the bundle inside the catheter. The wires are made of springy material so that the free wire ends separate widely outside the catheter. Other cylindrical ferrules are mounted in axially spaced position on bared portions of the other end of the bundle, and encircle all the wires, but each ferrule is in direct electrical contact with only one of the wires.

What is claimed is: 
     
       1. An electrode assembly for insertion into a catheter and establishing an electrical connection to an electronic circuit, said assembly comprising: a plurality of wires, each of said wires insulated from each other and each of said wires being electrically conductive and extending together side-by-side and having different lengths at one end thereof; .[.an insulated other wire.]. .Iadd.means .Iaddend.binding said plurality of wires together for substantially their entire length except for a free end at said one end of each of said wires;   an end portion of each of said free ends being bared of insulation;   an electrically conductive ferrule positioned on each of said bared portions on each of said free ends of said wires, said ferrules being spaced apart axially of each other when axially aligned with said free ends of said wires inside said catheter; and   a conductive means for connecting the other ends of each of said wires to said electronic circuit.   
     
     
       2. An electrode assembly as defined in claim 1, wherein said wires are made of springy material so that said free ends separate widely outside of said catheter. 
     
     
       3. An electrode assembly as defined in claim 1, further comprising insulation material forming insulative beads at opposite ends of each cylindrical ferrule. 
     
     
       4. An electrode assembly as defined in claim 3, wherein said conductive means comprises electrically conductive other elements positioned on bared portions of other ends of each of said wires. 
     
     
       5. An electrode assembly as defined in claim 4, wherein said .[.outer.]. .Iadd.other .Iaddend.conductive elements are spaced apart axially of each other on each of said wires. 
     
     
       6. An electrode assembly as defined in claim 5, wherein each of said other conductive elements in another cylindrical ferrule each enclosing each of said wires but electrically contacting only one of said wires. 
     
     
       7. An electrode assembly as defined in claim 6, wherein each of said other ferrules is held in place by conductive material on said wires. 
     
     
       8. An electrode assembly as defined in claim 1 wherein said plurality of wires is bifilar. .[.9. An electrode assembly as defined in claim 1, wherein said other wire is formed as another contact element and is 
     
     
        axially spaced between said ferrules and other ends of said wires..]. 10. An electrode assembly as defined in claim 1, wherein said plurality of 
     
     
        said wires is quadrafiler. .Iadd.11.  An electrode assembly as defined in claim 1 wherein said means binding said plurality of wires together is an insulated other wire. .Iaddend. .Iadd.12. An electrode assembly is defined in claim 11, wherein said other wire is formed as another contact element and is axially spaced between said ferrules and other ends of said wires. .Iaddend. .Iadd.13. In an electrode assembly for insertion into the heart of a person via a catheter or the like for establishing an electrical connection between heart tissue and an electronic circuit, said assembly comprising at least two wire leads insulated from each other and carrying relatively large contact portions on their ends, said wire leads being slidable relative to said catheter, the improvement wherein said wire leads are bound together in a manner providing discrete free distal end portions of fixed relative length,   said free end portions of said wire leads comprising oppositely bent springs that carry said relatively large contact portions,   when residing within said cannular passage, said wire portions being temporarily straightened in a manner known per se by the confining walls of said cannular passage, and lying alongside one another,   the fixed lengths of the free end portions of said wires being of preselected, only slightly different length in a manner to stagger within the cannular passage the positions of the relatively large contact portions, thereby to enable said cannular passage to be of minimum diameter,   whereby said assembly can enter via a single cannular passage to position multiple wire leads within one cavity of the heart, and   said free end portion of said wires can spring apart to their original bent shape within said one heart chamber upon relative withdrawal of said cannular passage, thereby to enable stable contact of said contact portions at multiple positions within a relatively small region of the   
     
     
        heart. .Iaddend. .Iadd.14.  The electrode assembly of claim 13 wherein at the other end of the assembly a number of axially spaced apart contact portions encircle all the wire ends, each of said contact portions being in direct electrical contact with only one of said wire leads. .Iaddend.