Cardiovascular catheter

INDUSTRIAL APPLICABILITY The present invention relates to a cardiovascular catheter, particularly a cardiovascular having a telescopic basket-shaped electrode array in which each arm is formed by a plurality of arms supporting a plurality of isolation electrodes. Regarding catheters.

[0002] Electrophysiology belongs to the specialized field of cardiology for the diagnosis and treatment of electrical abnormalities in the heart. Diagnosis is made using an electrode-supported catheter placed in the ventricle. Electrode elements laterally spaced around the catheter constitute the array in a very limited three-dimensional configuration, but the electrodes are essentially positioned along the catheter within the two-dimensional array. This three-dimensionality is understood to be due to the need to reduce the diameter of the catheter shaft when introducing the catheter into the heart via the veins and arteries of the body. Electrical abnormalities are typically diagnosed by detecting the process of electrical activation pathways along the inner surface of the heart in the ventricles over time. To this end, cardiologists place several catheters in one or more ventricles to obtain a better "figure" of this electrical activity. Occasionally, this electrical activity repeats the heartbeat periodically, i.e. fairly well. In such cases, the diagnosis is made by moving the electrodes from different regions and from point to point using a single catheter and comparing the activation time with the reference. This criterion may be an external EKG or other electrode catheter maintained in a stable position in the ventricle.

[0003] However, certain types of intraventricular electrical activity are not periodic. Examples include atrial flutter or atrial fibrillation, and ventricular tachycardia due to scars in the walls of the ventricles due to infarction. Such electrical activity is random from heartbeat to heartbeat. In order to analyze or "map" this type of electrical activity, a "figure" must be obtained during one heartbeat. In other words, all points on the map or figure must be obtained simultaneously within 1/10 of a second.

[0004] One solution to improve mapping is disclosed in US Pat. No. 4,552,212 by Gelinas et al. And No. 4,699,147 by Chilson et al. In these patents, the catheter has a number of reed-supporting arms extending into a three-dimensional array at the distal end, each arm having an inner central rib and electrodes separated along its length. In Chilson et al., The arm is anchored at its distal end, but moves freely within the outer catheter tube at its proximal end. The lead-supporting arm expands and contracts with respect to the outer catheter tube. The distal end of the catheter is guided to a designated area of the heart and released by a retracted lead-carrying arm into the external catheter canal. In the designated area, the arm extends from the external catheter tube to form a three-dimensional shape called an "elliptical envelope".

[0005] The catheters described by Chilson et al. Can hold a large number of electrodes at different related locations in the ventricle. By this means, a cardiologist can obtain a map of electrical activity within one heartbeat by simultaneously recording electrical signals from all of the electrodes. This is done by analyzing the spatial and temporal relationships of the electrical signals received by the electrodes.

[0006] A series of maps or diagrams can be created by rotating and / or moving the catheter longitudinally and recording electrical signals. Such a series of diagrams provides a "movement" diagram of continuous heartbeat, which better determines ectopic sites of activity or other active pathways that contribute to dysfunction. This type of information allows cardiologists to engage with other catheters in the destruction of the tissue that causes it. Such destruction of cardiac tissue is called "ablation", which is a fast-growing field of electrophysiology and requires maximal invasion and open cardiac surgery.

[0007] In Chilson et al., The arms move easily with respect to each other, thus changing the shape of the elliptical envelope over time and even when it is positioned in one place by the suction ventricle or as an effect of rotation. Change. Therefore, the spatial relationship of the electrodes is conditioned on an unknown change. This, in turn, gives a high degree of instability and error to any map of the electrical activity produced by the use of this catheter.

[0008] [Problems to be Solved by the Invention] An object of the present invention is to solve the above-mentioned problems of conventional electrophysiological mapping catheters.

[Means for Solving the Problems] The cardiac mapping catheter of the first aspect according to the present invention for solving the above problems is provided in (a) an elongated external catheter tube and (b) in the external catheter tube. Includes an elongated internal catheter, which includes (i) a tubular catheter shaft with a proximal end, a distal end and a central hole, and (ii) multiple distal ends and proximal ends. Flexible arms, (iii) proximal attachments that firmly secure the proximal ends of the plurality of flexible arms together, and (iv) the distal ends of the plurality of flexible arms together. The plurality of flexible arms are connected to the distal end of the catheter shaft at its proximal end, including a distal attachment to secure, and each of the flexible arms carries at least one electrode. And it has a reinforced spine, an electrode lead wire electrically connected to each electrode supported on the flexible arm, and a tubular sheath surrounding the reinforced spine and the lead wire, and the proximal attachment is said. It has a central hole that is fixed to the distal end of the catheter shaft and into which the lead wire penetrates. The inner catheter is located between a contraction position where the flexible arm is placed in the outer catheter tube and an extension position where the flexible arm extends outward from the distal end of the outer catheter tube. It is characterized in that it is movable in the longitudinal direction in the catheter tube, and that the flexible arm bends outward at the extension position to form a predetermined basket shape.

[0010] The second form of the cardiac mapping catheter according to the present invention comprises (a) an elongated outer catheter tube and (b) an elongated inner catheter provided in the outer catheter tube, and the inner catheter is (i). A catheter body having a proximal end and a distal end, (ii) a plurality of flexible arms extending from the distal end of the catheter body and having a distal end and a proximal end, and (iii). ) Consists of means for fixing the distal ends of the flexible arm together, the flexible arm curved outward between its proximal and distal ends and the central axis. Each of the flexible arms comprises a tubular sheath, a plurality of electrode lead wires, and a reinforced spine extending into the sheath, and the plurality of electrodes are far from the electrode lead wires. Electrically connected to the electrode lead wire at the distal end, the electrode is placed along the length of the sheath, and the reinforced spine has a semicircular cross section with a flat side facing the central axis. The inner catheter has a predetermined contraction position where the flexible arm is installed in the outer catheter tube and the flexible arm extends outward from the distal end of the outer catheter tube and curves outward. It is characterized in that it is configured to be movable in the longitudinal direction in the external catheter tube from the extension position forming the basket shape.

[0011] The third form of the cardiac mapping catheter according to the present invention is (a) a catheter body having a proximal end and a distal end, and (b) extending and distal from the distal end of the catheter body. A plurality of arms having an end and a proximal end, (c) means for fixing the distal ends of the plurality of arms together, and (d) the arm to the distal end of the catheter body. Including means for fixing the proximal end of The arms are curved outward between their proximal and distal ends to form a predetermined three-dimensional shape with a central axis, and each of the arms is in a flexible tubular sheath and in the sheath. The electrode lead wires include a plurality of extending electrode lead wires, each of the electrode lead wires has an insulating film and has a reinforced spine extending within the sheath, and the ends of the electrode lead wires are spaced apart from each other. The insulating film is stripped to form a plurality of electrodes at predetermined intervals along the length of the sheath, and the electrode lead wire is formed of the electrode lead wire. It passes through the sheath at a position facing the central axis of a predetermined three-dimensional shape and is wound around the sheath, and the tip of the end of each electrode lead wire is positioned at a position facing the central axis. It is characterized by that.

[0012] The electrophysiological mapping device according to the present invention is an elongated tubular outer catheter having a distal end, slidably provided in the outer catheter with respect to the outer catheter, and having an electrode at the distal end. The elongated inner catheter has an elongated inner catheter and an electronic recording device electrically connected to the electrode for electrically recording the electric signal received by the electrode, and the distal end of the inner catheter is the outer catheter. The internal catheter, which is stretchable and contractible with respect to the distal end of the catheter, is (a) a tubular catheter body having a proximal end and a distal end, and (b) the distal end of the catheter body. Includes a reinforced spine extending from, having a distal end and a proximal end, and having a flexible tubular sheath and a semicircular cross section extending into the sheath, the reinforced spine being proximal and distal. A plurality of flexible arms having an end and having a plurality of electrodes installed along the length of the sheath, (c) the above for fixing the proximal end of the reinforced spine together. Includes a polygonal first attachment fixed to the distal end of the catheter body, and (d) a second attachment for fixing the distal end of the reinforced spine together. When the distal end of the inner catheter extends from the distal end of the outer catheter, the arm curves outward to form a predetermined three-dimensional cage shape, and the plurality of electrodes It is characterized in that it is electrically connected to the recording device by an insulating lead wire extending from the recording device to the plurality of electrodes via the inner catheter and the sheath of the arm.

[0013] In a preferred embodiment, the lead wire has an insulating film, and the electrode is formed from an end segment of the lead wire that passes through and is wound around the sheath, and is wound around the sheath. The insulating film has been removed from at least a part of the end segment of the lead wire.

[0014] In a preferred embodiment, each of the proximal attachment and the distal attachment comprises a polygonal segment having a polygonal cross section, and the number of sides of the polygonal segment corresponds to the number of arms and the above. Each of the arm's reinforced spines has a proximal end that includes a flat surface that engages one side of the polygonal segment of the proximal attachment, and the distal end of the spine is of the distal attachment. Each of the proximal attachment and the distal attachment has a flat surface that engages with the flat surface of the polygonal segment, and each of the proximal attachments and the distal attachment provides means for fixing both ends of the spine of the arm to the polygonal segment. Further included.

[0015] In a preferred embodiment, the means for fixing the spine to the polygonal segment consists of a holding ring that fits tightly around the spine, thereby holding the spine against the sides of the polygonal segment. ..

[0016] In a preferred embodiment, five arms are provided.

[0017] In a preferred embodiment, the predetermined cage shape has a central axis, each of the spines has a semicircular cross section having a flat side, and the flat side of the spine faces the central axis.

[0018] In a preferred embodiment, for each of the arms, the spine and the lead wire forming the electrode are installed together in the corresponding sheath, whereby the lead wire forming the electrode is one of the sheaths. The spine is located relatively close to the central axis in the portion, and the spine is located relatively far from the central axis in a part of the sheath.

[0019] Optionally, the spine is made of a nickel-titanium alloy such as NITINOL (trade name).

[0020] In a preferred embodiment, each of the arms has a marker placed on the sheath at a predetermined position with respect to each other, and each of the markers is placed staggered with respect to a predetermined position of each marker on the other sheath. Has been done.

[0021] In a preferred embodiment, further includes means for fixing the proximal ends of the arms together.

[0022] In a preferred embodiment, the marker is further provided along the length of each of the arms, the marker being made of a material that is more prominent under X-rays than the material that forms the electrode, and each of the above. The markers on the arm are arranged so that they are offset from each other.

[0023] Optionally, the marker is made of a material such as platinum.

[0024] In a preferred embodiment, each of the first and second attachments comprises a mounting member having a polygonal cross section, the number of sides of the polygon corresponding to the number of spines, and the proximal end of the spine. The portion engages with the separation side of the attachment member of the first attachment, and the distal end of the spine engages with the separation side of the attachment member of the second attachment, and each of the attachment members further described above. Includes means for fixing the spine to the mounting member.

[0025] In a preferred embodiment, each of the arms has a marker on it, which is made of a material that is more prominent under X-rays than the material that forms the electrode, and the markers on each of the arms are staggered from each other. Arranged in a relationship.

[0026] To summarize the means for solving the above problems, the electrophysiological mapping catheter according to the present invention comprises an outer catheter and an inner catheter. The inner catheter has a tubular shaft that extends longitudinally to the outer catheter. A plurality of flexible arms are provided at the distal end of the shaft, and each of the arms carries a plurality of separation electrodes. The flexible arm takes the form of a cage and is secured to the proximal attachment at its proximal end and to the distal attachment at its distal end. The shaft moves longitudinally within the external catheter, and the arm and electrode are contractible and extendable with respect to the external catheter tube. When the arm extends from the tube of the catheter, the arm bends outward to form a "basket" and the electrodes form a three-dimensional array.

[0027] Each of the above arms includes a reinforced spine surrounded by a tubular flexible sheath having a generally circular cross section. It is preferable that the reinforced spine faces inward, that is, the flat surface has a semicircular cross section in the axial direction of the catheter. It is preferable that the spine is inside the outer surface of the tubular sheath and the rest of the tubular sheath is filled with an insulating electrode lead wire.

[0028] The electrode is preferably formed on the arm by passing the insulating lead wire through the wall of the tubular sheath, winding the lead wire around the tubular sheath, and adhering to the tubular sheath. .. Further, the insulating material is stripped from the outer surface of the lead wire around which the sheath is wound. The electrode lead wire extends from the arm to the stimulator and / or recording device through the holes in the proximal attachment and the inner catheter shaft.

[0029] The proximal and distal attachments include polygonal rod-like segments, the flat side of the segment corresponding to the number of spines and engaging with the flat surface of the spine. A pinch ring is placed around the spine to hold the spine in proper orientation on the polygonal rod segment. In a preferred embodiment, the spine is preferably made of a superelastic material, in particular a nickel-titanium "shape memory" alloy. Such a material allows the arm to return to its curved shape after being extended outward from the external catheter.

An embodiment of the present invention will be described below with reference to the accompanying drawings.

[Examples] FIGS. 1-7 show preferred electrophysiological mapping devices according to the present invention.

FIG. 1 shows a partial perspective view of an electrophysiological mapping device according to the present invention, including an internal catheter, an external catheter, and an activation-recording device, showing a state in which the internal catheter is contracted into the external catheter. .. That is, the device includes an electronic stimulation and / or recording device 4, an inner catheter 6, and an outer catheter tube 8. The outer catheter tube 8 serves to carry the inner catheter 6 into the mapping site, for example, the ventricle, and to withdraw the inner catheter 6 from the mapping site. The inner catheter 6 is slidable in the longitudinal direction within the outer catheter tube 8. A hemostatic valve, not shown, is provided at the proximal end of the outer catheter tube to prevent backflow of blood from the hole in the outer catheter tube 8.

The internal catheter 6 has an elongated tubular catheter shaft 7 and five electrode-supporting arms 9 at the distal end of the catheter shaft 7. The inner catheter 6 has an extension position in which the arm 9 shown in FIG. 2 extends completely out of the distal end of the outer catheter tube 8 relative to the outer catheter tube 8, and the arm 9 generally shown in FIG. 1 is outward. Moves to and from the contraction position that contracts into the catheter tube 8.

FIG. 2 is an enlarged view of the distal end of each catheter of FIG. 1, where the inner catheter extends from the outer catheter, forming a cage-shaped electrode at the distal end of the inner catheter. .. At this extension position, the arm 9 curves outward to form a "cage" structure.

Each arm 9 has a separation set electrode 11 shown here as a pair of five bipolar electrodes. In the illustrated embodiment, the five electrode pairs are approximately evenly spaced. However, the number and spacing of the electrodes may vary as desired. Further, a single electrode may be used instead of a pair of bipolar electrodes.

[0036] The arm 9 is fixed to the proximal attachment 12 at its proximal end and similarly to the distal attachment 14 at its distal end. The proximal attachment 12 is sequentially fixed to the distal end of the catheter shaft 7. The catheter shaft 7 has a central hole 13 extending from its proximal end to its distal end. Shaft 7 is made of high-strength braided stainless steel or other high-strength wire or fiber hardened or referenced herein by, for example, US Patent Application No. 07 / 645,230, filed January 24, 1991. It is preferable to have a tubular wall 10 sandwiched between inner and outer layers made of flexible polyurethane. This high torque shaft structure allows a doctor to control the orientation of the electrode cage in the ventricle by rotating the catheter shaft 7. In this case, the shaft penetrates through the patient's body, usually the groin or neck. The shaft 7 further has a nylon stiffened sleeve 15 that reinforces the interior of the tubular wall 10.

FIG. 5 is a cross-sectional view of the arm 9. The arm 9 has a flexible insulating material, for example a plastic outer tube 18 such as a flexible polyurethane tube structure. Inside this plastic tube structure are a plurality of electrode lead wires 20, each of which has an insulating film and a central conductive wire core. The wire 20 extends from the electrode 11 through the plastic tube structure of the arm 9, the proximal attachment 12 and the holes in the shaft 7 to the stimulus and / or recording device. In this embodiment, there are 50 reed wires 20 corresponding to 10 electrodes 11 supported on each of the 5 arms 9. The number of electrodes, and therefore the electrode lead wires, can be varied as needed.

[0038] The lead wires 20 are divided into five bundles 22, each bundle 22 containing ten lead wires corresponding to ten electrodes 11 supported by each particular arm 9. The proximal end of the split wire bundle 22 is terminated by a split plug connector 24, which is inserted into the stimulus / recording device 4. The total number of lead wires 20 in each bundle 22 is equal to the number of electrodes 11 on each corresponding arm. Therefore, if there are 5 electrodes on each arm, then there are 5 reed wires in the corresponding bundle. If there are 5 electrode pairs, then there will be 10 electrode leads in the bundle. Each bundle of lead wires 22 is contained within an insulating flexible tube, which tube is sequentially connected to the plug connector 24.

[0039] In FIG. 3, each electrode 11 is formed by passing a lead wire 20 through an outer tube 18 of an arm 9. The lead wire is tightly wrapped around the tubular tissue 18 and adhered, and the insulating film is stripped from the outer surface of the lead wire, that is, the surface in contact with the heart wall to expose the metal of the lead wire.

[0040] The electrode lead wire 20 is preferably a metal that is inert to blood. MONEL400 (a trademark of the Hunteinton Alloy Products Department of International Nickel Co., Inc. of Hunteinton, West Virginia) is currently preferred. MONEL is a group of corrosion resistant alloys containing nickel and copper as the main elements and carbon, manganese, iron, sulfur and silicon in very small amounts. Some such alloys contain a small amount of aluminum, titanium and cobalt. MONEL 400 has the additional advantage of not being easily visible under fluoroscopy like platinum. Therefore, the electrodes may be small and all may be uniformly arranged with the same dimensions.

[0041] More than that, with materials that are opaque to X-rays, uniform separation of electrodes is not desirable because it is difficult to distinguish which arm is in which position. For example, in Chilson et al., US Pat. No. 4,699,147, the electrodes on the arm are non-uniformly separated from the electrodes on each other arm. When the electrodes are non-uniformly separated like Chilson's other devices, it is difficult to see which arm is under which X-ray. In a preferred embodiment of the invention, the electrode pairs on each arm are evenly spaced relative to each other and located at positions corresponding to the electrodes on each arm, but are non-uniformly spaced on each arm. It may be arranged so as to be offset from the electrodes on the other arm.

The uniform spacing of the electrodes usually makes it difficult to determine which arm is in which position. However, according to one aspect of the invention, the marker 38 is positioned on the arm in a jagged or spiral manner at different positions along each arm. These markers are preferably made of a material that can be easily identified under fluoroscopy, such as platinum, and may be in the form of a band or ring fixed around each arm.

[0043] The arm 9 is supported by a flexible rib or spine 25 having a semicircular cross section. The spine 25 is preferably made of a superplastic material, such as a nickel-titanium alloy of about 54 to 57% nickel, preferably 55% and the balance preferably 45% titanium. Such materials exhibit superelasticity. That is, it can be deformed by an external force, for example, bending, and returns to its original shape when the stress is removed. Currently the preferred material is marketed under the trade name NITINOL by US Nitinol of Seratoga, California. The superelastic spine 25 makes the arm 9 of the car expandable and contractible with respect to the external catheter tube 8 and, for example, bends from the pulsating ventricle to return to the normal shape even when extremely deformed.

[0044] The spine 25 has an insulating film, such as a polyurethane paint, that helps hold it in place and shield it from lead wires. The lead wire 20 and the spine 25 are positioned in the tube 18 such that the spine 25 occupies the outward facing portion of the tube 18, while the lead wire 20 occupies the inward facing portion of the tube 18. The words "inner" and "outer" refer to the axis or centerline of the car. The spine 25 with a semi-circular cross section has greater lateral stability and is flexible enough to open in the shape of a "cage" when the inner catheter 6 extends and bends relative to the outer catheter tube 8. Therefore, it is preferable to a spine having a circular cross section having the same cross-section region.

Positioning of the electrode lead wire 20 inside the tube 18 separates the lead wire 20 from the heart wall. This allows the lead wire portion used for the electrode to pass through the tube 18 at a distance from the heart wall, thereby providing a smoother electrode surface. It is preferable that the hole in the tube 18 on which the lead wire 20 extends and the end of the lead wire are covered and fixed with an adhesive such as polyurethane at a position where they do not come into contact with the ventricular wall.

The metal portion of each spine 25 extends to the plastic tube 18 at each end and is attached to the two fittings 12 and 14 as detailed in FIGS. 4-7. The proximal attachment 12 has a polygonal rod segment 26 with a shaft hole. The rod segment 26 is preferably metal. The number of sides of the polygonal rod segment 26 is equal to the number of spines 25. The flat surface of each spine 25 is positioned flat with respect to the side of the polygonal rod segment 26 in the same orientation as the spine 25 is located at the time of car formation.

The outer pinching ring 27 made of metal or the like holds the spine 25 in place with respect to the sides of the polygonal rod segment 26. Adhesives such as polyurethane or epoxy can preferably be used for permanent fixation of the spine, polygonal rod segment 26 and clamp ring.

[0048] The proximal attachment 12 is fixedly placed within the distal end of the internal catheter shaft 7 with, for example, epoxy, polyurethane or other adhesive. The distal end of the nylon sleeve 15 extends and abuts to the proximal end of the polygonal rod segment 26 and the clamp ring 27. The electrode lead wire 20 from each arm 9 passes through a shaft hole in the polygonal rod segment 26 and extends to the nylon sleeve 15.

The distal attachment 14 is substantially identical to the proximal attachment 12 and has a polygonal rod segment 29. The spine 25 is fixed to each side of the polygonal rod segment 29 and is fixed there by the outer holding ring 30. However, no holes are needed in segment 29 as the lead wire is not present in the distal attachment 14. Further, it is preferable that the outer plastic tip member 31 is provided. It is preferred that the member be round at its distal end, allowing the internal catheter to slide through veins or arteries without trauma and prevent trauma in the ventricles. The tip member 31 can be fixed using, for example, an adhesive such as epoxy or polyurethane.

[0050] The distal attachment 14 may have the same dimensions as the proximal attachment 12, or may be smaller if desired. The fixtures 12 and 14 hold the spine 25 in the proper angular orientation with respect to each other and thus maintain the proper spacing of the arms 9 and the proper orientation of the car. This is important because the cardiovascular catheter must be received by the suction heart wall and rotated during the electrophysiological mapping process. In addition, the spine 25 undergoes bending or other forces while expanding and contracting with respect to the external catheter.

The car has five arms 9. This number is the most preferable number. As shown in Figure 8, there are 10 asymmetric rotation positions. That is, the arms are arranged so as to form five pentagonal corners, and each corner corresponds to a rotation position. The 36 ° rotation of the car forms five additional rotation positions. Due to the use of five arms, the car looks very neat and round during rotation when viewed axially. This feature greatly facilitates intraventricular installation and control because the ventricles are not round and irregular.

[0052] A large number of arms is not preferred because it makes it more difficult to differentiate the electrodes and makes it more difficult for the inner catheter to fit into the outer catheter. A small number of arms is practical in that the differentiation of the electrodes is small and easy, but it is not preferable because the mapping becomes complicated.

Upon use, the internal catheter 6 is placed in a vein or artery, followed by an external catheter 8 for placement in the ventricles. The outer catheter 8 holds the cage arm 9 inward in a contracted position to allow all catheters consisting of the inner catheter 6 and the outer or induction catheter 8 to pass under the veins and arteries into the ventricles. Once the distal end of the catheter reaches the desired ventricle at an appropriate position, the outer catheter 8 is retracted to bend the arm 9 to a predetermined "cage" position. The electrode 11 contacts the wall of the ventricle at this position. The additional outward movement of the arm and the pressure on the heart wall are obtained by pressing the inner catheter shaft 7 from top to front, thereby expanding the car outward. When the mapping is complete, the external catheter returns to the top of the car to contract the arm and is finally removed with the arm.

Internal mapping or cage catheters have several advantages as described above. For example, fixing the spine of a car at its distal and proximal ends forms a very laterally stable car. This stability is important for holding the catheter in a stable position in the beating ventricle.

[0055] The fixture that holds the distal and proximal ends of the spine together, the flat sides of the spine that match the flat sides of the polygon, ensure accurate three-dimensional arm placement.

The semi-circular cross section of the spine improves lateral stiffness as compared to a round cross section of the same area, thereby increasing the lateral stability of the car.

The use of a superelastic material such as NITINOL on the spine results in bending, contraction and distortion without a permanent deformation that allows the car to be recognized.

The coupling of the five cage arms to the catheter shaft with high torque forms a cage that can be easily controlled and oriented in the ventricle.

The adoption of a semi-circular cross section in the spine makes it possible to fill the outer surface of the tubular tissue of the arm with the spine and leave an inner surface for the lead wire. The lead wire thus extends into the vascular tissue and terminates along the inner surface side of the arm away from the heart wall after wrapping around the vascular tissue. The holes and ends of each outlet are coated and glued. Only the outwardly facing portion of the lead wire that wraps around the tubular tissue is stripped to form the electrode.

[0060] The electrode is thus formed quite small and is easily identified by fluoroscopy from the platinum ring marker. The ring markers allow easy identification of each arm of the car when placed in a jagged or spiral manner on different arms.

[0061] The car formed as described above is not only laterally rigid, but actually elastic, and by pushing the inner catheter forward after the car is exposed to the ventricles by withdrawal of the outer catheter. By itself, it easily becomes the shape of the ventricle. This ensures that all electrodes are in good contact with the inner surface of the heart to generate a strong electrical recording signal.

[0062] Although the present invention has been described above as a preferred embodiment, it will be obvious to those skilled in the art that various modifications can be made.

BRIEF DESCRIPTION OF THE DRAWINGS [FIG. 1] FIG. 1 is a partial perspective explanatory view of an electrophysiological mapping apparatus according to the present invention.

2 is an enlarged view of the distal end of each catheter of FIG. 1. FIG.

3 is an enlarged view of the electrode pair of FIG. 2. FIG.

FIG. 4 is a longitudinal sectional view of the distal end of the internal catheter according to the present invention.

5 is a partially enlarged cross-sectional view of the arm of FIG. 2. FIG.

6 is a cross-sectional view of the proximal attachment of FIG. 2. FIG.

7 is a cross-sectional view of the distal attachment of FIG. 2. FIG.

FIG. 8 is a schematic view of an asymmetrical position of 10 rotations of an arm according to the present invention.

[Code description] 4 ... Electrical stimulation and / or recording device 6 ... Inner catheter 7 ... Catheter shaft 8 ... Outer catheter tube 9 ... Arm 10 ... Wall 11 ... Electrode 12 ... Proximal Mounting 14 ... Distal Mounting 15 ... Sleeve 20 ... Lead Wire 22 ... Bundle 25 ... Spine 26,29 ... Polygonal Rod Segment 27 .. .Pinch ring 38 ... Marker