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Publication numberUS3533403 A
Publication typeGrant
Publication dateOct 13, 1970
Filing dateMay 10, 1967
Priority dateMay 10, 1967
Publication numberUS 3533403 A, US 3533403A, US-A-3533403, US3533403 A, US3533403A
InventorsWoodson Riley D
Original AssigneeWoodson Riley D
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Combination heart catheter and electrode
US 3533403 A
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Description  (OCR text may contain errors)

United States Patent Inventor Riley D.-W00dson I 2012 W. 50th Terrace, Shawnee Mission, Kansas 66205 Appl. No. 637,572

Filed May 10, 1967 Patented Oct. 13, 1970 COMBINATION HEART CATHETER AND ELECTRODE 15 Claims, 6 Drawing Figs.

us. c1 128/206, 128/2,128/2.1,128/172.1,128/404 Int. Cl A611) 5/04 Field of Search 128/2, 2.05.

References Cited UNITEDSTATES PATENTS 1,967,015 7/1934 Wappler 1223/407x 2,102,270 12/1937 Hyams 1213/1722x 2,729,211 [/1956 Peter 128/21 3,249,103 5/1966 Woodhouse.. 1213/21 3,421,499 1/1969 Brayetal 128/2 FOREIGN PATENTS Ad. 57,824 4/1953 France 128/407 Primary Examiner-Delbert B. Lowe A1mrney Schmidt, Johnson, Hovey, Williams and Chase ABSTRACT: A catheter tube is provided with a conductive tip at its head which is employed as a deep-probing electrode in conjunction with the catheter. A thread-like wire is embedded in the tip, the latter being composed of an electrically conductive, synthetic resin materiaL The tubular wall of the catheter is formed by inner and outer, superimposed, tubular layers between which the wire extends in a helical path along the length of the catheter.

Patented Oct. 13, 1970 3 3,533,403

INVENTOR Rf/ey 0. M/aodson I 'ITORNEYIS COMBINATION HEART CATHETER AND ELECTRODE An inserter for the cathetenelectrode device employs an elongated, slit tube which receives a connector body therewithin to which the rear end of the catheter is joined. A rib projects from the connector body through the slit in the tube and mounts an electrical terminal and fluid couplings. A connection is made between the electrode wire and the terminal through the connector body, and a passage therein communicates the fluid couplings with the catheter. The forward end of the slit tube is joined to a needle holder to which a handle is removably attached to aid in the insertion of a hollow needle extending from the holder and communicating with the tube. The catheter is advanced along the tube, through the needle holder and the hollow needle by movement of the connector body relative to the tube.

The primary object of this invention is to provide a combination catheter and deep-probing electrode having greater functional flexibility and scope of usefulness than catheters and electrodes employed heretofore on an individual basis, and which may be advantageously utilized in the diagnosis and treatment of internal disorders.

As a corollary to the foregoing object, it is an important aim of this invention to provide a combination catheter and deepprobing electrode device capable of conducting current between the electrode and external electrical apparatus with the fluid receiving or discharging aperture of the catheter precisely placed within the body, and spaced a known distance from the electrode, to enable the catheter to be utilized with external medical apparatus with exact knowledge as to the position of the catheter aperture.

Another important object is to provide such a combination device in which the catheter and the lead to the electrode pass into the body integrally by simultaneous insertion in a single procedure.

Still another important object of the invention is to provide such a device that may be accurately positioned within the body as required by reference to the wave form display of an electrocardiograph connected to the electrode, or by X-ray or radiation location techniques- A further and important aim of the instant invention is to provide an improved inserter for the combination device which, prior to use, protects-the catheter and electrode and the hollow needle utilized to initiate insertion.

In the drawing:

FIG. 1 is a side elevational view of the inserter;

FIG. 2 is an enlarged, longitudinal sectional view of the inserter illustrated in FIG. 1, revealing the catheter and electrode disposed therewithin;

FIG. 3 is a cross-sectional view taken along line 3-3 of FIG.

FIG. 4 is a cross-sectional view taken along line 4 4 of FIG.

FIG. 5 is a greatly enlarged, longitudinal sectional view of the head portion of the catheter; and

FIG. 6 is a sectional view taken along line 6-6 of FIG. 2.

An inserter for the combination catheter and electrode device to be subsequently described is broadly denoted by the numeral 10 and also serves as a protective case for the device prior to use thereof. The inserter 10 includes a flexible protector tube I2 having a longitudinal cut or slit 14 therein extending the entire length of tube 12 to split the latter into a pair of resilient, longitudinally extending sections 16 which are normally closed against each other at the cut 14. The forward extremity 18 of tube 12 is telescoped into a longitudinal opening 20 in an elongated needle holder 22. Extremity 18 is secured to holder 22 by a tape wrapping 23 provided with a strip-off tab 23a. The forward end of holder 22 is reduced and presents a frusto-conical, external taper 24, an elongated protector cap 26 being slipped over the tapered end of holder 22 and secured by a friction fit by virtue of an internal taper of its central bore 28 complemental to taper 24.

A hollow needle 30 is seated in holder 22 in longitudinal alignment with the central opening 20 extending therethrough, it being appreciated that the sharp end of needle 30 projects from holder 22 and is normally housed within bore 28 of the cap 26. Holder 22 and cap 26 are of circular cross-sectional configuration throughout except at their proximal ends which are formed with flats 32 for ease in gripping the two components and manually removing cap 26.

A catheter 34 extends within tube 12=longitudinally thereof, the head 36 of catheter 34 being normally received by and disposed within the central opening 20 in holder 22. The size of opening 20 converges to a diameter slightly greater than that of catheter 34 in the central portion of holder 22 and continues to the forward end of holder 22 at the same effective diameter to guide catheter 34 through needle 30 during use of the instrument. The rearward end 38 of catheter 34 is telescoped over an elongated, hollow nose 40 integral with a connector body 42 extending longitudinally of tube 12 and positioned therewithin for sliding movement longitudinally of tube I2. As will be discussed more fully hereinafter, catheter 34 is composed of a flexible, synthetic resin material and hence end 38 thereof is readily slipped over nose 40 and held by a friction fit or other suitable means to positively secure the catheter 34 to body 42.

The connector body 42 is provided with an integral, relatively thin, longitudinally extending member or rib 44 which projects from tube 12 through cut 14. Rib 44 supports a flat base 46 having an electrical socket 48 and a pair of fluid couplings 50 thereon. The front and rear ends 52 and 54 of rib 44 converge to a vertical edge, as is most clearly illustrated in FIG. 6 to effect a smooth separation of sections 16 along the length of rib 44. A hook-shaped locking dog 53 is integrally formed on base 46 above and forward of front end 52, the dog 53 being receivable within an annular groove 55 on holder 22 after catheter 34 is inserted, as will be discussed hereinafter.

An L-shaped handle 56 of molded plastic construction is removably secured to holder 22, the shorter leg 58 of handle 56 having a slot 60 in its outer end, defining a pair of flexible wings 62 which clasp holder 22 when handle 56 is in place. To facilitate attachment of handle 56 and to assure that the same is securely affixed, holder 22 is provided with a frustoconical, longitudinal taper 64 complemental to the configuration of the base of slot 60. It should be understood that the length of tube 12 from holder 22 to the forward end 52 of rib 44 would be approximately 3 feet to adapt the instrument for use in cardiac diagnosis and treatment where needle 30 would enter the body in a vein of the arm. Tube 12 is provided with lineal measuring indicia in the form of spaced graduations 66 (FIG. 1) along its length between holder 22 and rib 44. The leading edge '52 of rib 44 serves as an index which registers with graduations 66 as catheter 34 is advanced, as will be discussed hereinafter.

Referring particularly to FIG. 5, the head 36 of catheter 34 is shown greatly enlarged and reveals that catheter 34 has a tubular wall 68 composed of an inner layer 68a and an outer layer 68b superimposed upon inner layer 68a to form a solid wall structure. A thread-like conductive element in the form of a fine, noncorrosive wire 70 extends the length of wall 68 and is sandwiched between the two layers 68a and 68b. Wire 70 is wound on inner layer 68a in a helical pattern and has a terminal portion 72 extending from the forward end 74 of wall 68, terminal portion 72 being bent back within the tubular wall 68 and embedded in a plug 76 of electrically conductive, synthetic resin material.

Multiple openings 78 in wall 68 are filled by integral locking projections 80 on plug 76, the latter being formed by introducing the resin in its flowable state into the central passage 82 defined by wall 68. The resin is permitted to fill openings 78 and form a core within head 36 prior to solidification thereof. The resin is loaded with conductive particles to render the material electrically conductive, an electrical connection with wire 70 being effected by the embedding of terminal portion 72 therewithin. The rounded tip 84 of head 36 is an integral part of plug 76 and is formed therewith to provide an electrode for contact with the body or body fluids upon insertion of catheter 34 thereinto.

The layers 68a and 68b of wall 68 are composed of a suitable synthetic resin with one of the layers comprising a radiopaque substance such as barium loaded Teflon. The outer layer 68b is an extrusion formed on the inner layer 680 after wire 70 is in place. Thus. the catheter tubing may be formed in long, continuous, extruded sections and then cut to form individual tubes 68. A pair of diametrically opposed aperatures 86 adjacent plug 76 extend completely through layers 68a and 68b and communicate-with passage 82, thereby providing the necessary catheter orifices for ingress or egress of fluid.

Referring to FIG. 2, a lead 88 is brought from the end 38 of catheter 34 to a terminal 90 in the form of a conductive sleeve within socket 48 for receiving a suitable male connector (not shown). Lead 88 connects with wire 70 at end 38, or it may comprise an extension of wire 70, and it extends through a passage therefor in body 42. rib 44. and base 46 to terminal 90. A longitudinal passage 92 in body 42 communicates the hollow nose 40 thereof with couplings 50 via branch passages, one ofthe branches being illustrated at 94.

All of the components of inserter 10, with the exception of needle 30 and terminal 90, are preferably of molded plastic construction to provide a throwaway item which is discarded after use. The material selected should be electrically nonconductive to provide socket 48 and body 42 with desired insulating properties to electrically isolate lead 88 and terminal 90 from fluids flowing in passage 92. Additionally, it is requisite that tubular wall 68 of catheter 34 be composed of a nonconductive material in order to provide an insulated covering for wire 70.

in use, needle 30 is introduced into a body vessel, and body 42 is advanced by applying pressure manually to the rear thereof while grasping tube 12. Thus, body 42 is pushed along tube 12 such as by the thumb of the physician, with the leading edge 52 of rib 44 serving to separate sections 16 as body 42 advances. Due to the resilient nature of sections l6, it will be appreciated that the same are wedged away from each other by rib 44 but return into contact at cut 14 at the trailing edge 54 of rib 44. Manifestly, the alignment of leading edge 52 with graduations 66 gives the physician precise knowledge of the depth of insertion of catheter 34 by a direct reading. Depending upon the particular use of the device, terminal 90 would be connected to desired electrical apparatus such as an electrocardiograph, while the fluid couplings 50 are provided in order to communicate the catheter passage 82 with flow and pressure measuring devices and fluid sources or pumping apparatus as the case may be.

As an aid in initial insertion, handle 56 is attached to needle holder 22 by first slipping wings 62 over the tube 12 adjacent the rearward end of holder 22. Handle 56 is then advanced in a forward direction until the increasing diameter of holder 22 provides a sufficient friction fit to hold the handle securely in place. Handle 56 greatly facilitates grasping of the inserter, which must be firmly gripped in order to force needle 30 into an artery or vein. It should be understood that the average diameter of needle holder 22 would be only on the order of one-fourth of an inch, rendering direct grippingof the holder difficult.

After catheter 34 is fully inserted strip-off tab 23a is pulled to break the tape wrapping 23 and enable tube 12 to be separated from holder 22. The tube 12 is then discarded and the nose 40 of connector body 42 is inserted into opening in holder 22. It should be noted that the external configuration of nose 40 and the forward end portion of body 42 is complementary to the interior of opening 20 to be contacted upon insertion of nose 40 and body 42 thereinto. Dog 53 and groove 55 are positioned such that body 42 and holder 22 become interlocked as nose 40 seats in opening 20, the lock being effected by a snap action as dog 53 flexes and then seats in groove 55. With dog 53 received in groove 55, it will be appreciated that body 42 and holder 22, being a single unit are more easily handled by the physician and may be conveniently taped to the patient or a suitable external support. Handle 56 is removed and discarded prior to joining holder 22 and body 42 together.

Some of the capabilities and advantages of the instant invention will now be outlined. Since it is known that consistent and very marked or significant changes in electrocardiogram wave forms occur in very small distances when a deep electrode probe attached by leads to an electrocardiograph machine is moved into and through the cavities of the heart, it is possible to accurately determine the location and position of the electrode with relation to the heart and its features. This characteristic permits the accurate and precise positioning of the catheter apertures 86 since the apertures are disposed in fixed dimensional relationship to the tip or electrode 84. (The spacing between tip 84 and apertures 86 would be on the order of one-half inch to 3 inches.) Such positioning can be effected by reference to the visual wave form of the electrocardiograph machine attached to wire via terminal 90. Alternatively. due to the radiopaque nature of the tubular layer 68a or 68b, the catheter may be located by X-ray photography or fluoroscopy.

The advantages of precise positioning of the combination device of the instant invention by electrocardiographic reference are, for example, the elimination of the necessity to move the patient under possibly dangerous circumstances, the ability to execute procedures at the patient (bedside or elsewhere) with portable equipment, the ability to diagnose very rapidly and accurately by virtue of the fast and accurate insertion and placement, the ability to institute correct remedial action at once, such as catheter functions or heart pacing, and the capability to perform functions of catheter and electrode simultaneously including electrical stimulation of the heart 'and other medical techniques.

Although an important use of the instant invention is in connection with the heart and the circulatory system other important uses include the following, and are presented as exemplary only of the broad scope of applications to which the instant invention is adapted:

. For intra atrial electrocardiogram traces for diagnosis of atrial arrythmia;

2. For driving cardiac assist (pulsed) units or other devices normally paced by the atrial (or other) wave of an electrocardiograph impulse;

3. For intraventricular diagnosis and evaluation of arrythmias;

4. For vector cardiographic evaluation of the relative status of different areas of the heart wall in selecting patients for coronary artery surgery;

. As a pressure monitor (either simultaneously with the use of the electrode or otherwise) for monitoring the central venous pressure in the evaluation of the right heart filling pressure;

6. As a monitor as aforesaid in the obtaining of diagnostic pressure traces at caval, atrial or ventricular levels;

7. As a sampling catheter (during use of the electrode or otherwise) for drawing evaluation samples at caval, atrial or ventricular levels (to determine among other data the oxygen saturation), and also at the coronary and sinus levels;

8 As a carrier for a phonocardiograph to transmit to external equipment the necessary measurements for producing phonocardiograms;

9. As a catheter conduit for the injection of cardiac drugs to an accurately determined point of discharge using the EKG monitor electrode;

10. As a catheter conduit for central transfusions or other injections by the catheter; and

l 1. For repetitive pacing of either the atria or the ventricles or both,

I claim: 7

l. A medical device for insertion into a body vessel comprising:

a catheter provided with an elongated, tubular wall of insulating material having opposed, inner and outer surfaces and having an end for entry into said vessel, said inner surface defining a fluid passage;

a thread-like, electrically conductive element disposed within said wall between said surfaces and extending longitudinally thereof from said end, whereby the wall provides an insulating covering for said element in surrounding relationship thereto;

electrical connection means coupled with said element remote from said end, whereby to adapt the element for connection to external electrical apparatus;

a conductive plug in said passage adjacent said end and rigidly secured to said wall, closing said passage and presenting a conductive tip on said end exposed for contact with said vessel;

said wall having an aperture therein spaced from said end and communicating with said passage; and

said element having a terminal portion extending from said wall and connected to said plug to electrically couple said tip to the element.

2. The invention of claim 1, said plug being composed of a conductive, synthetic resin material, said portion being embedded in said plug.

3. The invention of claim 1, said wall having an opening therein between said end and said aperture, said plug having an integral locking projection extending outwardly into said opening.

4. The invention of claim 1, said wall having a tubular inner layer and an outer layer superimposed thereon, said element extending between said layers in a helical path.

5. The invention of claim 4, said outer layer having physical characteristics resulting from having been extruded onto said innerlayer.

6. The invention of claim 4, one of said layers comprising a radiopaque substance.

7. ln catheterizing apparatus:

a flexible protector tube having a longitudinal cut therein,

presenting a pair of resilient, longitudinal sections normally closed against each other;

a catheter having a pair of opposed ends and a head defined by one of said ends; said catheter extending longitudinally of said tube therewithin with the other of said ends disposed in the tube;

an elongated connector body slidably received within said tube and having a hollow nose communicating with said catheter; said other end of the catheter being secured to said nose, said head being provided with an electrode;

a thread-like, electrically conductive element in said catheter coupled with said electrode and extending the length of the catheter; said body being provided with a longitudinally extending, relatively thin member received between said sections and projecting from said tube through said cut;

terminal means on said member:

electrical connection means in said body coupling said terminal means with said element; and

a fluid coupling on said member, said body having a passage therewithin communicating said coupling with said catheter through said nose.

8. The invention of claim 7:

said tube having an extremity normally adjacent said head;

there being an elongated, hollow needle holder secured to said extremity and communicating with said tube;

a hollow needle communicating with said holder and extending longitudinally outwardly therefrom away from said extremity; and

said tube, holder and needle being disposed in longitudinal alignment with one another to permit advancement of the catheter therethrough upon movement of said body relative to said tube.

9. The invention of claim 8 and a handle for inserting the needle into a body vessel, said handle being detachably secured to said holder.

10. The invention ofclaim 9:

said handle having a pair of spaced, flexible wings defining a slot therebetween receiyingthe holder; and

said holder being longitu inally tapered, whereby to facilitate attachment of the handle thereto and provide a friction fit between the wings and the holder upon relative movement of the latter and the handle with the holder received in said slot and clasped by the Wings.

11. The invention of claim 8:

and a removable protector cap telescoped over said holder with said needle extending into the cap; and

said cap and said holder having complemental tapers to provide a friction fit therebetween.

12. The invention of claim 8:

said holder receiving said nose upon forward movement of the body toward the holder;

said member having a forward end provided with a locking dog; and

said holder being provided with means engageable by said dog as said nose is inserted into the holder to lock the latter and the body together.

13. The invention of claim 7:

said tube having lineal measuring indicia thereon spaced longitudinally thereof; and

said member having an index for registration with said in dicia, whereby the displacementof the body relative to the tube in advancing the catheter may be directly read.

14. A medical device for insertion into a body vessel comprising:

a catheter provided with an elongated, tubular wall of insulating material presenting a fluid passage and having an end for entry into said vessel;

a thread-like electrically conductive element disposed within said wall and extending longitudinally thereof from said end, whereby the wall provides an insulating covering for said element in surrounding relationship thereto;

electrical connection means coupled with said element remote from said end, whereby to adapt the element for connection to external electrical apparatus;

a plug composed of a conductive, synthetic resin material and disposed in said passage adjacent said end, closing said passage and presenting a conductive tip on said end;

said wall having an aperture therein spaced from said end and communicating with said passage; and

said element having a terminal portion extending from said wall and embedded in said plug to electrically connect said tip to the element.

15. A medical device for insertion into a body vessel comprising:

a catheter provided with an elongated, tubular wall of insulating material presenting a fluid passage and having an end for entry into said vessel;

a thread-like, electrically conductive element disposed within said wall and extending longitudinally thereof from said end, whereby the wall provides an insulating covering for said element in surrounding relationship thereto;

electrical connection means coupled with said element remote from said end, whereby to adapt the element for connection to external electrical apparatus;

a conductive plug in said passage adjacent said end, closing said passage and presenting a conductive tip on said end;

said wall having an aperture therein spaced from said end and communicating with said passage;

said element having a terminal portion extending from said wall and connected to said plug to electrically couple said tip to the element;

said wall having an opening therein between said end and said aperture; and

said plug having an integral locking projection extending outwardly into said opening.

Referenced by
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Classifications
U.S. Classification600/381
International ClassificationA61B5/0408, A61B5/0215, A61B5/042, A61M25/00, A61N1/05
Cooperative ClassificationA61B5/0215, A61B5/042, A61M25/005, A61N1/05
European ClassificationA61B5/0215, A61B5/042, A61N1/05