JP7179320B2 - catheter - Google Patents

Description

The present invention relates to catheters.

Conventionally, catheters that are inserted into blood vessels of humans and animals have been used. At present, a catheter having a multi-wound structure in which a plurality of wires are wound around a flexible tubular body has been proposed and put into practical use (see, for example, Patent Document 1).

In a catheter having a multiple winding structure, insulation is achieved by forming an insulation layer on each wire, but considering the thickness of the entire catheter, the insulation layer must be made as thin as possible. When a signal from a living body is detected by an electrode disposed on the distal end of the catheter, the cell potential generated from the living body ranges from -70 mV to 30 mV, so there is no problem even if the insulating layer is thin.

On the other hand, when providing an electrical pulse signal to the living body using a catheter, it is necessary to apply a relatively high voltage (for example, ± 400 V when returning atrial fibrillation to sinus rhythm) pulse voltage (for example, , Non-Patent Documents 1 and 2). In this case, since a thin insulating layer does not have sufficient dielectric strength, it is necessary to provide a thick insulating layer 110 on the electric wire 100 to which the defibrillation voltage (eg, ±400 V) is applied, as shown in FIG.

Japanese Patent No. 6144824 S Mark Sopher, 6 others, "Low energy internal cardioversion of atrial fibrillation resistant to transthoracic shocks", Heart (1996), No. 75, p635-638, Internet <URL: http://heart.bmj.com/content /75/6/635> E Alt, 5 others, "Efficacy of a new balloon catheter for internal cardioversion of chronic atrial fibrillation without anesthesia", Heart (1998), No. 79, p128-132

However, as shown in FIG. 12, the electric wire 100 for defibrillation provided with the thick insulating layer 110 has a larger diameter (that is, thicker) than the other electric wires 200, and thus loses its flexibility. As a result, a catheter wound with such a thick electric wire 100 also lacks flexibility, which may make it difficult for the catheter to conform to a complicated blood vessel shape. In addition, winding the electric wires 100 and 200 having different thicknesses causes a step S (irregularities) on the outer peripheral surface of the catheter, so that the step S may get caught on the inner wall of the blood vessel when the catheter is inserted into the blood vessel. Otherwise, the electric wires 100 and 200 may become frayed.

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and an object of the present invention is to suppress the occurrence of steps on the outer peripheral surface of a catheter having a defibrillation function, while ensuring flexibility. do.

In order to achieve the above object, a first catheter according to the present invention is a catheter constructed by winding a plurality of wires, including at least two high-voltage wires to which a defibrillation voltage is applied, around a flexible tubular body. The plurality of wires includes intervening wires disposed between high voltage wires. A second catheter according to the present invention is a catheter comprising a plurality of wires including at least two high-voltage wires to which a defibrillation voltage is applied, and a flexible tubular body, wherein the flexible A groove having a predetermined depth is formed spirally on the outer peripheral surface of the tubular body, and the plurality of wires includes an intervening wire arranged between the high-voltage electric wires and is embedded in the groove. be. A third catheter according to the present invention is a catheter constructed by winding a plurality of wires, including one high-voltage wire to which a defibrillation voltage is applied and a ground wire, around a flexible tubular body, The plurality of lines includes intervening lines arranged between the high voltage line and the ground line. A fourth catheter according to the present invention is a catheter comprising a plurality of wires including one high-voltage wire to which a defibrillation voltage is applied and a ground wire, and a flexible tubular body, A groove having a predetermined depth is provided spirally on the outer peripheral surface of the flexible tubular body, and the plurality of wires includes an intervening wire arranged between the high-voltage wire and the ground wire, and the groove It is buried.

By adopting such a configuration, the intervening wire is arranged between the high-voltage wires to which the defibrillation voltage (for example, ±400V) is applied, thereby preventing the high-voltage wires from coming into direct contact with each other. Therefore, it is not necessary to increase the thickness of the insulating layer of the high-voltage wire in order to increase the dielectric strength, so that flexibility of the catheter can be ensured. In addition, since the diameter of the high-voltage wire can be made close to the diameter of the other wires (or the same as the diameter of the other wires), it is possible to suppress the occurrence of steps (unevennesses) on the outer peripheral surface of the catheter. .

In the catheter according to the present invention, an insulated wire made of a resin material can be employed as the intervening wire.

With this configuration, the insulated wire made of a resin material is arranged between the high-voltage wires as an intervening wire, so that the high-voltage wires can be effectively insulated from each other.

A non-connected wire that is not connected to a power supply can be employed as an intervening wire in the catheter according to the present invention.

If such a configuration is adopted, the unconnected electric wire that is not connected to the power source is used as the intervening wire, so there is no need to separately prepare an insulated wire.

In the catheter according to the present invention, a signal detection wire for detecting signals can be employed as an intervening wire.

With this configuration, the signal detection line for detecting signals is effectively used as an intervening line, so there is no need to separately prepare an insulated line.

In the catheter according to the present invention, a medium voltage wire that is set to an intermediate potential of the defibrillation voltage can be employed as the intervening wire.

By adopting such a configuration, since the medium voltage wire set to the intermediate potential of the defibrillation voltage is arranged between the high voltage wires as an intervening wire, the withstand voltage of the high voltage wire can be halved.

In the catheter according to the present invention, the medium voltage wire can be used as the high voltage wire to which the defibrillation voltage is applied when the high voltage adjacent to the medium voltage wire is broken.

By adopting such a configuration, it is possible to apply the defibrillation voltage to the medium voltage wire (make the medium voltage wire function as a high voltage wire) even if the high voltage adjacent to the medium voltage wire is disconnected.

In the catheter according to the present invention, the diameter of the insulated wire, unconnected wire, signal detection wire, or medium voltage wire employed as the intervening wire can be the same as that of the other wires.

When such a configuration is adopted, steps (unevennesses) are formed on the outer peripheral surface of the catheter in order to make the diameter of the insulated wire, unconnected wire, signal detection wire, or medium piezoelectric wire adopted as the intervening wire the same as that of the other wires. can be suppressed.

Advantageous Effects of Invention According to the present invention, in a catheter having a defibrillation function and having a multi-winding structure, it is possible to suppress the occurrence of steps on the outer peripheral surface while ensuring flexibility.

1 is a configuration diagram for explaining the overall configuration of a catheter according to a first embodiment of the present invention; FIG. Fig. 2 is an enlarged side view (including a partial cross-sectional view) for explaining the configuration of the tube of the catheter according to the first embodiment of the present invention; FIG. 2 is an explanatory view (enlarged view of part III in FIG. 1) for explaining the electrode arrangement of the catheter according to the first embodiment of the present invention; FIG. 3 is a diagram showing a differential amplifier circuit for electrocardiographic signal detection; FIG. 10 is a diagram showing a biphasic output circuit; 4 is a diagram showing a signal waveform detected at an input terminal when a pulse signal is output from the output terminal in the electrode arrangement shown in FIG. 3; FIG. FIG. 4 is an enlarged view showing another example of electrode arrangement of a catheter; 8 is a diagram showing a signal waveform detected at an input terminal when a pulse signal is output from the output terminal in the electrode arrangement shown in FIG. 7; FIG. FIG. 4 is an enlarged view for explaining another example of electrode arrangement of the catheter according to the first embodiment of the present invention; FIG. 4 is a perspective view (including a partial cross-sectional view) for explaining the configuration of the tube of the catheter according to the second embodiment of the present invention; FIG. 4 is a cross-sectional view of a tube of a catheter according to a second embodiment of the invention; FIG. 2 is an enlarged side view (including a partial cross-sectional view) for explaining the configuration of a conventional multi-winding catheter having a defibrillation function.

Hereinafter, each embodiment of the present invention will be described with reference to the drawings. It should be noted that each of the following embodiments is merely a suitable application example, and the scope of application of the present invention is not limited to this.

<First embodiment>
First, the configuration of a catheter 1 according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 9. FIG. A catheter 1 according to this embodiment has a defibrillation function, and as shown in FIG. A first DC electrode group 40 and a second DC electrode group 50 are provided on the outer periphery.

As shown in FIG. 2, the tube 2 has a flexible tubular body 2a and a plurality of wires (electric wires 10 and insulated wires 20) spirally wound around the outer circumference of the flexible tubular body 2a. there is The flexible tubular body 2a is a flexible tubular member made of a non-conductive material (for example, a resin material such as polytetrafluoroethylene), and has a lumen (not shown) therein. formed.

As shown in FIG. 2, the wires 10 spirally wound around the outer periphery of the flexible tubular body 2a include at least two high-voltage wires 11 to which a defibrillation voltage (for example, ±400 V) is applied. . In this embodiment, the diameter of the high voltage wire 11 is set to be the same as the diameter of the other wires 10 . An insulating film 10a (11a) made of a resin material such as polyesterimide or polyamideimide is formed on the outer periphery of the electric wire 10 (including the high-voltage electric wire 11). The diameter of the wire 10 (including the high-voltage wire 11) and the thickness of the insulating film 10a (11a) can be appropriately set according to the specifications of the catheter 1 and the like. For example, when the diameter of the electric wire 10 (high-voltage electric wire 11) is set to 0.24 mm, the thickness of the insulating film 10a (11a) can be set to 0.017 mm.

As shown in FIG. 2, the insulated wire 20 spirally wound around the outer periphery of the flexible tubular body 2a is arranged between two high-voltage wires 11 so that the high-voltage wires 11 are in direct contact with each other. It prevents this and functions as an intervening wire in the present invention. The insulated wire 20 is made of a resin material such as nylon or polyurethane, and its diameter is set to be the same as the diameter of the electric wire 10 . In this embodiment, as shown in FIG. 2, the insulated wire 20 is also arranged between the high-voltage wire 11 and the other wire 10 so that the high-voltage wire 11 and the other wire 10 are in direct contact with each other. prevent this from happening.

A handle 3 is removably coupled to the proximal end of tube 2 via connector 4, as shown in FIG. It is configured to house a steering element such as a let. The steering element is housed within the lumen of the flexible tubular body 2a that constitutes the tube 2. FIG.

The first DC electrode group 40 and the second DC electrode group 50 are arranged at positions sandwiching the atria inside the human or animal heart. The first DC electrode group 40 and the second DC electrode group 50 are each composed of a plurality of electrodes 41, as shown in FIG. I try not to concentrate on one point.

Here, the electrode arrangement of the first DC electrode group 40 will be described with reference to FIGS. 3 to 9. FIG. Since the electrode arrangement of the second DC electrode group 50 is the same as the electrode arrangement of the first DC electrode group 40, the explanation thereof is omitted.

The first DC electrode group 40 has a plurality of ring-shaped electrodes 41, as shown in FIG. Some of the multiple ring-shaped electrodes 41 are used to apply energy for defibrillation, and the rest of the multiple ring-shaped electrodes 41 are input terminals (for example, first input terminal 42a and second input terminal 42b) and output terminals (eg, first output terminal 43a and second output terminal 43b).

In this embodiment, a differential amplifier circuit as shown in FIG. 4 is used to detect an electrocardiographic signal. Therefore, if a large potential change occurs between the first input terminal 42a and the second input terminal 42b, an excessive input is applied to the circuit, which may cause saturation or damage to the circuit. , protection circuits, etc. are considered. However, once an excessive input is applied to the circuit, the electrocardiogram signal cannot be detected correctly until the potential between the first input terminal 42a and the second input terminal 42b returns to the state before the excessive input. can't.

Therefore, in this embodiment, as shown in FIG. 3, the first input terminal 42a and the second input terminal 42b are arranged adjacent to each other, and a defibrillation terminal is provided between the first input terminal 42a and the second input terminal 42b. By not arranging the ring-shaped electrode 41, it is possible to reliably detect the electrocardiogram signal. FIG. 6 shows the relationship between the first input terminal 42a and the second input terminal 42b when pulse signals are output from the first output terminal 43a and the second output terminal 43b using the biphasic output circuit as shown in FIG. It shows the signal waveform detected during the period. As shown in FIG. 6, it can be seen that the biphasic signal waveform is correctly detected.

When the second output terminal 43b is arranged between the first input terminal 42a and the second input terminal 42b as shown in FIG. 7, a signal waveform as shown in FIG. 8 is detected. In this example, it can be seen that the detection electrodes (input terminals 42a and 42b) are affected by the output signal, noise such as ringing is generated, and the biphasic signal waveform is not correctly detected. For this reason, it is preferable to place the two input terminals 42a, 42b adjacent to each other (Fig. 3) instead of placing the output terminal 43b between the two input terminals 42a, 42b (Fig. 7). As shown in FIG. 9, by placing a reference terminal (ground terminal) 44 on the circuit between the two input terminals 42a and 42b, interference from the output terminals 43a and 43b can be suppressed.

Next, a method for using the catheter 1 according to this embodiment will be described.

First, the tube 2 of the catheter 1 is inserted into a blood vessel of a human or an animal, and the first DC electrode group 40 and the second DC electrode group 50 provided on the outer circumference of the tube 2 are allowed to reach the inside of the heart. A second DC electrode group 50 is placed on either side of the atrium. Next, using each input terminal and each output terminal of these electrode groups 40 and 50, an electrocardiogram signal inside the heart is detected. Depending on the situation, a defibrillation voltage is applied to the heart using defibrillation ring electrodes 41 provided in the electrode groups 40 and 50 . Thus, the catheter 1 according to the present embodiment performs a defibrillation function while monitoring electrocardiographic signals inside the heart.

In the catheter 1 according to the embodiment described above, the insulated wire (intervening wire) 20 is arranged between the high-voltage wires 11 to which the defibrillation voltage (for example, ±400 V) is applied, so that the high-voltage wires 11 are separated from each other. Avoid direct contact. Therefore, it is not necessary to increase the thickness of the insulating layer 11a of the high-voltage wire 11 in order to increase the withstand voltage, so the flexibility of the catheter 1 can be ensured. Moreover, since the diameter of the high-voltage wire 11 can be made the same as the diameter of the other wires 10, it is possible to suppress the occurrence of steps (unevennesses) on the outer peripheral surface of the catheter 1. FIG.

Further, in the catheter 1 according to the embodiment described above, the insulated wire 20 made of a resin material is arranged between the high-voltage wires 11 as an intervening wire, so that the high-voltage wires 11 can be effectively insulated from each other. .

<Second embodiment>
Next, the configuration of the catheter according to the second embodiment of the present invention will be described using FIG. 10 and the like. The catheter according to this embodiment is obtained by changing the configuration of the tube 2 in the catheter 1 according to the first embodiment, and other configurations are substantially the same as those of the first embodiment. Therefore, the configuration different from the first embodiment will be mainly described, and the configuration common to the first embodiment will be denoted by the same reference numerals and detailed description thereof will be omitted.

The catheter according to this embodiment has a defibrillation function as in the first embodiment, and includes a tube 2A as shown in FIG. A handle 3 (see FIG. 1) similar to that of the first embodiment is connected to the tube 2A, and a first DC electrode group 40 and a second DC electrode group 50 similar to those of the first embodiment are provided on the outer periphery of the tube 2A. (see FIG. 1) is provided. The handle 3, the first DC electrode group 40, and the second DC electrode group 50 are the same as those in the first embodiment, so detailed description thereof will be omitted.

The tube 2A, as shown in FIGS. 10 and 11, has a flexible tubular body 2Aa and a plurality of wires (electric wires 10 and insulated wires 20). The flexible tubular body 2Aa is a flexible tubular member made of a non-conductive material as in the first embodiment, and a lumen 2Ab is formed therein as shown in FIG. It is As shown in FIGS. 10 and 11, a spiral groove 2Ac having a predetermined depth is provided on the outer peripheral surface of the flexible tubular body 2Aa. As shown in FIGS. 10 and 11, a plurality of wires (electric wires 10 and insulated wires 20) are embedded in the grooves 2Ac. Therefore, the depth of the groove 2Ac is set to be approximately the same as the diameter of the electric wire 10 (insulated wire 20).

Inside the lumen 2Ab of the flexible tubular body 2Aa in this embodiment, as shown in FIG. 11, a blade 2Ad is provided for covering the inner peripheral surface of the flexible tubular body 2Aa to maintain its shape. It is The blade 2Ad can be made of a material such as metal. 10 and 11, the outer side of the flexible tubular body 2Aa (the outer side of the electric wire 10 and the insulated wire 20 embedded in the groove 2Ac) is made of a non-conductive material. It is covered with an outer skin 2Ae.

The electric wire 10 is the same as that in the first embodiment. That is, the electric wire 10 includes at least two high-voltage electric wires 11 to which a defibrillation voltage (for example, ±400V) is applied. The diameter of the high-voltage electric wire 11 is the same as that of the other electric wires 10, and an insulating film is formed on the outer circumference of the electric wire 10 (including the high-voltage electric wire 11). The diameter of the wire 10 (including the high-voltage wire 11) and the thickness of the insulating film can be appropriately set according to the specifications of the catheter. The insulated wire 20 is the same as in the first embodiment. That is, the insulated wire 20 prevents direct contact between the two high-voltage wires 11 by being arranged between the two high-voltage wires 11, and functions as an intervening wire in the present invention. The insulated wire 20 is made of a resin material, and its diameter is set to be the same as the diameter of the electric wire 10 .

In the catheter according to the embodiment described above, the insulated wire (intervening wire) 20 is arranged between the high-voltage wires 11 to which the defibrillation voltage (eg ±400 V) is applied, so that the high-voltage wires 11 are directly connected to each other. can prevent direct contact. Therefore, it is not necessary to increase the thickness of the insulating layer of the high-voltage wire 11 in order to increase the withstand voltage, so that flexibility of the catheter can be ensured. Moreover, since the diameter of the high-voltage wire 11 can be made the same as the diameter of the other wires 10, it is possible to suppress the occurrence of steps (unevennesses) on the outer peripheral surface of the catheter.

In addition, in the catheter according to the embodiment described above, the insulated wire 20 made of a resin material is arranged between the high-voltage wires 11 as an intervening wire, so that the high-voltage wires 11 can be effectively insulated from each other.

In each of the above-described embodiments, an example in which the insulated wire 20 made of a resin material is used as the intervening wire arranged between the high-voltage electric wires 11 is shown, but other wires may be employed as the intervening wire. . For example, an unconnected wire that is not connected to a power source can be used as the intervening wire. If the non-connected wire that is not connected to the power source is used as the intervening wire, there is no need to separately prepare an insulated wire. At this time, it is preferable to set the diameter of the non-connected wire to be the same as that of the other wires, because it is possible to suppress the occurrence of steps (unevennesses) on the outer peripheral surface of the catheter 1 .

A signal detection line for detecting a signal can also be employed as the intervening line. If the signal detection line for detecting signals is effectively used as an intervening line in this way, there is no need to separately prepare an insulated line. At this time, it is preferable to set the diameter of the signal detection wire to be the same as that of the other wires, because it is possible to suppress the occurrence of steps (unevennesses) on the outer peripheral surface of the catheter 1 . When the signal detection line is used as the intervening line, the application of the defibrillation voltage to the high-voltage wire 11 and the application of the voltage to the signal detection line are not performed at the same time.

Further, as the intervening wire, a medium voltage wire that is set to an intermediate potential of the defibrillation voltage can be employed. By arranging the medium voltage wire set at the intermediate potential of the defibrillation voltage as an intervening wire between the high voltage wires 11 in this way, the dielectric strength of the high voltage wire 11 can be halved. At this time, it is preferable to set the diameter of the medium-voltage wire to be the same as that of the other wires, because it is possible to suppress the occurrence of steps (unevennesses) on the outer peripheral surface of the catheter 1 . Also, if one of the high-voltage wires 11 adjacent to the medium-voltage wire is broken, the medium-voltage wire can be used as the high-voltage wire 11 to which the defibrillation voltage is applied.

Further, in each of the above embodiments, an example was shown in which two high-voltage wires 11 to which a defibrillation voltage of ±400 V was applied were used. A single high-voltage wire to which a defibrillation voltage is applied and a ground wire can also be employed. In such a case, an intervening wire (for example, an insulated wire 20) is arranged between one high-voltage wire and the ground wire, and the intervening wire is brought into contact with the high-voltage wire. This eliminates the need to increase the thickness of the insulation layer of the high-voltage wire in order to increase the dielectric strength, and the diameter of the high-voltage wire can be made the same as that of the other wires, thereby ensuring the flexibility of the catheter. In addition, it is possible to suppress the occurrence of steps (unevennesses) on the outer peripheral surface of the catheter.

The present invention is not limited to the above-described embodiments, and any design modifications made by those skilled in the art to these embodiments are also included in the scope of the present invention as long as they have the features of the present invention. be. That is, each element provided in each of the above embodiments and its arrangement, material, conditions, shape, size, etc. are not limited to those illustrated and can be changed as appropriate. Moreover, each element provided in each of the above-described embodiments can be combined as long as it is technically possible, and a combination of these is also included in the scope of the present invention as long as it includes the features of the present invention.

DESCRIPTION OF SYMBOLS 1... Catheter 2a*2Aa... Flexible tubular body 2Ac... Groove 10... Electric wire 11... High-voltage electric wire 20... Insulated wire (intervening wire)

Claims (9)

A catheter configured by winding a plurality of wires including at least two high-voltage wires to which a defibrillation voltage is applied around a flexible tubular body,
The plurality of wires includes intervening wires arranged between the high-voltage wires,
The catheter , wherein the intervening wire is a medium voltage wire that is set to an intermediate potential of the defibrillation voltage . A catheter comprising a plurality of wires including at least two high voltage wires to which defibrillation voltage is applied, and a flexible tubular body,
A groove having a predetermined depth is spirally provided on the outer peripheral surface of the flexible tubular body,
The plurality of wires includes an intervening wire arranged between the high-voltage wires and is embedded in the groove ,
The catheter , wherein the intervening wire is a medium voltage wire that is set to an intermediate potential of the defibrillation voltage . The catheter according to claim 1 or 2 , wherein the medium voltage wire can be used as a high voltage wire to which defibrillation voltage is applied when the adjacent high voltage wire is disconnected. 4. The catheter according to any one of claims 1 to 3, wherein the diameter of the medium voltage wire is the same as the diameter of the other wires. A catheter constructed by winding a plurality of wires including a high-voltage wire to which a defibrillation voltage is applied and a ground wire around a flexible tubular body,
A catheter, wherein the plurality of wires includes an intervening wire disposed between the high voltage wire and the ground wire. A catheter comprising a plurality of wires including a high-voltage wire to which a defibrillation voltage is applied and a ground wire, and a flexible tubular body,
A groove having a predetermined depth is spirally provided on the outer peripheral surface of the flexible tubular body,
The catheter, wherein the plurality of wires includes an intervening wire arranged between the high voltage wire and the ground wire and embedded in the groove. The catheter according to claim 5 or 6 , wherein the intervening wire is an insulated wire made of a resin material. 7. The catheter of claim 5 or 6 , wherein the intervening wire is an unconnected wire that is not connected to a power source. 7. The catheter of claim 5 or 6 , wherein the intervening wire is a signal detection wire for detecting signals.

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