JPH1147286A - Lead for implantation in organism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily realize a removal through veins even under a state wherein the tip end of a lead is covered with a firm fibrous film, and prevent a cardiac muscle from generating an excessive inflammatory reaction by a method wherein a lead body is constituted of an electric conductor having flexibility, of which the outer peripheral surface is covered with an insulating material which is compatible with an organism. SOLUTION: As a lead is being used, the periphery of the lead is placed under a state being covered with a firm fibrous film, and an endocardium fixing means 42 made of a material which is decomposable in an organism, is dossolved in the body. As a result, the endocardium fixing means 42 such as a tine equipped with a protuberance (a mooring part 42c) which has conventionally become an obstacle on the contrary when a lead is removed due to infectuous deseases and a pacing mulfunction, etc., has already been dissolved if a specified period of time has passed after the implantation of the lead, and does not become an obstacle for the removal of the endocardium fixing means 42. That is, the lead can be removed as is. Also, when a fibrous film covering the threaded part 34a of an electrode insulating part 34 is firm, a removal can be performed while a different electrode block 32 is being pulled into tubal bodies 50, 51.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a lead for implanting a living body, and more particularly to a lead implanted in a living body for use with a living body implanting device such as a cardiac pacemaker or an implantable defibrillator. The present invention relates to a lead for implanting a living body having a fixing means for fixing an electrode to an endocardium in order to prevent the electrode from shifting or coming off.

[0002]

2. Description of the Related Art Conventionally, various types of biological implantable leads (hereinafter, simply referred to as leads) configured to be implantable in a living body for use with a biological implanting device such as a cardiac pacemaker or an implantable defibrillator. It has been known.

[0003] Generally, the lead is configured as follows. That is, a connector for providing electrical stimulation to the heart or sensing electrical stimulation of the heart and a connector for making electrical and mechanical connections to a cardiac pacemaker or implantable cardioverter-defibrillator. And an electrical conductor and a biocompatible insulating coating provided between the electrode and the connector for transmitting a predetermined electrical signal between the electrode and a cardiac pacemaker or an implantable cardioverter-defibrillator. Having a lead body.

Particularly, in a transvenous lead used for transvenous use, an electrode and a part of a lead body are inserted into a heart and a vein, while the remaining lead body not inserted into a vein is connected via a connector. Connected to a connection terminal of a cardiac pacemaker or an implantable cardioverter-defibrillator arranged outside the vein.

[0005] The electrodes of the transvenous lead are maintained at an appropriate position in the heart in order to exert its performance sufficiently.

For this purpose, a transvenous lead is generally provided with fixing means for fixing the distal end of the lead, on which the electrodes are disposed, to a fiber such as a trabecula or a chord in the heart just by anchoring it. I have. The fixing means as described above is passively fixed to the endocardial tissue, and is therefore called passive endocardial fixing means.

FIG. 7 is an external perspective view showing three examples of such passive endocardial fixation means. A passive endocardial fixation means 80 called a tine shown in FIG. 7A is provided with a antler-shaped fixation member 103 and a fixation member 10.
3 the electrode 10 provided at the tip of the lead 104
2 is immobilized relative to the endocardium. FIG. 7B
Passive endocardial fixation means 82 called fins shown in FIG.
As shown in FIG.
Four fin-shaped fixing members 105 are provided at 0-degree intervals, and the fixing members 105 cause the electrodes 102 provided at the distal ends of the leads 104 to be immobilized with respect to the endocardium.
The passive endocardial fixation means 84 called a flange shown in FIG. 7 (C) has a flange-shaped fixation member 10 whose outer diameter increases as the distance from the electrode 102 increases.
6 is provided, and the electrode 102 provided at the distal end of the lead 104 is immobilized with respect to the endocardium by the fixing member 106.

On the other hand, a lead of a type called active endocardial fixation means in which a screw electrode is screwed into an endocardium has been put to practical use, but any fixation means is mechanically fixed to tissue. In this way, it is intended to prevent the electrode from being displaced and the lead from coming off.

[0009]

However, when the conventional lead for implanting a living body provided with the passive endocardial fixation means as described above is used for a long time, the passive endocardial fixation means becomes fibrous cap. As a result, when the living body implantation lead has to be removed due to an infection, pacing failure, or the like, the protrusion of the passive endocardial fixation means (for example, fixation members 103, 105, 10
Conversely, 6) becomes an obstacle, making it extremely difficult to remove the lead intravenously. In particular, it is said that transvenous withdrawal is almost impossible when the period of five years or more has elapsed after the lead implantation, since the lead tip is covered with a strong fibrous cap. For this reason, when it is absolutely necessary to remove the lead due to a serious infection or the like, the invasive thoracotomy must be resorted to.

[0010] Even with active endocardial fixation means using a screw electrode, which is said to be relatively easy to remove a lead, the longer the period of use, the greater the probability of myocardial perforation due to the sharp portion of the screw crest. In addition to being high, the aggressive invasion of the myocardium causes an excessive inflammatory response, which causes an excessive stimulation threshold.

[0011] As a solution to the above-mentioned problems of the prior art, Heisei 9 filed by the same applicant as the present invention has been proposed.
Japanese Patent Application No. 39208 proposes a lead in which an endocardial fixing means is made detachable. According to the invention,
The endocardial fixation means is detached from the lead in the living body, and the lead is removed while leaving the detached endocardial fixation means in the living body. However, it is not possible to completely deny the possibility that the endocardial fixation means left in the living body may cause complications such as blood flow inhibition.

[0012] The present invention has been made in view of the above-mentioned problems, and even if the tip of the lead is covered with a strong fibrous cap after the lead is implanted, the transvenous withdrawal is performed. It is an object of the present invention to provide a lead for living body implantation which can be easily realized and has no possibility of causing an excessive inflammatory reaction to myocardium.

[0013]

Means for Solving the Problems The above-mentioned problems are solved,
In order to achieve the object, the present invention has the following configuration. That is,

A lead for implanting a living body, comprising: a lead body for transmitting an electric signal generated by the device for implanting a living body; and at least one electrode for transmitting an electric signal transmitted from the lead body to a myocardium. A connection means for mechanically and electrically connecting the device to the first end of the lead body, an electrode at one end and an energizable support for connection to the lead body; An insulative portion covering the portion, and a bioerodible detachably mounted near the second end of the lead body so as to cover at least a part of the outer periphery of the insulative portion to fix the electrode to the endocardium. An endocardial fixation means made of a conductive material at the second end of the lead body, wherein the lead body is made of a flexible electrical conductor whose outer peripheral surface is covered with a biocompatible insulating material. When Characterized in that it is configured.

Further, the lead for implanting a living body according to the present invention further comprises a first electrically conductive screw hole portion which is mechanically fixed to the electric conductor and is covered with a biocompatible insulating material. A first tube having a contact with the first tube,
A second tube covered with a biocompatible insulating material and having a second screw hole made of the insulating material, wherein the endocardial fixation means has a third screw hole inside. The support has a screw portion that is screwed with the first and second screw holes,
The insulating portion has a screw portion that is screwed with the first, second, and third screw holes, and the support is formed through an opening formed on the first end side of the lead body. A stylet for releasing the threaded state of the third screw hole by rotating the stylet to be inserted and for accommodating the insulating portion and the support in the first and second tubes. And an engaging portion that engages with

Further, in the lead for implanting a living body according to the present invention, the endocardial fixing means further has a screw hole inside, and the insulating portion has a screw portion to be screwed with the screw hole. The threaded state of the threaded portion is released from the threaded hole portion by rotating the lead body from the end of the lead body.

Further, the endocardial fixing means of the lead for implanting a living body according to the present invention is characterized in that a tine, a fin, and a flange-like mooring portion are formed.

The biodegradable material of the bioimplant lead according to the present invention is a material selected from the group consisting of proteins, aliphatic polyesters, polycarbonates, polyorthoesters, polyamic acids, and hyaluronic acid esters. Alternatively, it comprises a copolymer or a mixture of two or more materials selected from the group.

According to the above configuration, when it becomes necessary to remove a lead due to an infection or pacing failure, the lead can be easily removed by traction.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION

[First Embodiment] Hereinafter, preferred embodiments of the present invention will be specifically described with reference to the accompanying drawings. First, FIG. 1 is an external perspective view showing the overall configuration of a lead 1 that can be implanted in a living body. In this figure, a lead 1 has a proximal end 4b as a first end and a distal end 4a as a second end, and is constituted by a lead body 4 having a predetermined length of flexibility. ing.

The proximal end 4b of the lead body 4 is provided with a connector portion 9 connected to a connector of a cardiac pacemaker or an implantable defibrillator (not shown). 6 and seal portions 7, 7 are provided coaxially as shown. On the other hand, a coaxial portion 4c is formed continuously with the proximal end 4b. This coaxial portion 4c is
It is detachably fixed to a mechanical connector of a living body implanting device such as a cardiac pacemaker or an implantable defibrillator. Further, an opening 8 is provided at an end of the proximal end 4b, and a stylet (survey needle) described later is inserted through the opening 8.

On the other hand, at the distal end 4a of the lead body 4,
Electrodes 2, 20 and endocardial fixation means 42 are provided as shown. FIG. 1 is an external perspective view of a coaxial wire type bipolar lead. However, the present invention is not limited to this. For example, a parallel wire type bipolar lead or a monopolar lead may be used.

The lead 1 configured as described above is used by being connected to a cardiac pacemaker or an implantable defibrillator. At this time, the endocardial fixation means 42
Maintain zero endocardial contact.

Next, FIG. 2A is a sectional view of a main part of the lead body 4 in the present embodiment, and FIG. 2B is an enlarged sectional view of the distal end 4a. In the present embodiment, the lead body 4 mainly includes the electrode block 32, the endocardial fixing means 42, and the tube 5.
0, 51, a conductor coil 12, and an insulating film 14. The Seki electrode block 32 is mainly composed of the electrode 2,
It comprises an electrode support 33 and an electrode insulator 34.

The electrode insulator 34 has a threaded portion 34a on the outer peripheral surface.
Is provided, and is firmly fixed with an adhesive or the like so as to cover the outer periphery on the distal side of the electrode support 33. In FIG. 2B, a portion of the screw portion 34a on the proximal end side is held in a state of being screwed with the screw hole portion 51b inside the tubular body 51, and the remaining portion on the distal end side of the screw portion 34a is It is held in a state of being screwed into the screw hole 42 b inside the endocardial fixation means 42. The tube 51 is mechanically connected to the distal surface 50c of the tube 50 and the insulating film 14 by using an adhesive or the like.

The electrode support 33 is provided with a screw portion 33a and a groove portion 33c as shown. In FIG. 2B,
A part of the screw portion 33a of the electrode support 33 is held in a state of being screwed into the screw hole 50b of the tube 50, and the electrode support 33 is held.
The surface 33d abuts on the tube 50 so that the related electrode block 32 does not go further in the distal direction. In addition,
The electrode support 33 is also electrically connected to the tube 50.

Therefore, the outer peripheral surface of the electrode block 32, that is, the threaded portion 33a and the threaded portion 34a are screwed into the threaded hole 50b of the tube 50 and the threaded hole 51b of the tube 51, and the threaded portion 34a is Further, it is screwed into the screw hole 42b of the endocardial fixing means 42.

The lead body 4 is composed of a coil-shaped conductor coil 12 that transmits electric signals and has flexibility, and an insulating coating 14 that covers the outer peripheral surface of the conductor coil 12. The tip 12 of the conductor coil 12
a has a smaller winding diameter and the inner peripheral surface 50c of the tube body 50.
Are press-fitted and are electrically and mechanically connected. The tube 50 is mechanically connected to the insulating coating 14 by using an adhesive or the like.

As the material of the electrode insulator 34 and the tube 51, a biocompatible electric insulating material is preferable, and examples thereof include polyurethane, high molecular weight polyethylene, and polytetrafluoroethylene. The electrode insulator 34 is made of diamond-like carbon (DLC).
It may be an insulating coating such as Also,
The electrode insulator 34 is provided with an endocardial fixation means 42 as described later.
When is dissolved, it comes into direct contact with the living body, and therefore, great care must be taken in selecting the material and processing the screw portion 34a.

The materials of the electrode support 33, the conductor coil 12, and the insulating film 14 are the same as those of a general pacing lead.

The tube 50 has a screw hole 50b on the inside.
Is a conductive rigid body processed, and as the material thereof, a corrosion-resistant material such as platinum, a platinum alloy, titanium, a titanium alloy, a cobalt alloy, and stainless steel is preferable.

As shown in FIG. 2B, the electrode block 32 protruding from the tubes 50 and 51 is fixed to the endocardial fixing means 4 made of a biodegradable insulating material by a screw portion 34a.
The second screw hole 42b is screwed.

In FIG. 2B, the endocardial fixation means 42
Although it is a tine-shaped member provided with the mooring portion 42c, the shape of the mooring portion 42c may be any shape as long as it can be fixed to the endocardium. For example, a fin shape, a flange shape, and the like can be given.

On the other hand, the anchoring portion 42c of the endocardial fixing means 42
Is an obstacle to removal when lead 1 must be removed for some reason. The endocardial fixation means 42 is a means for fixing the lead 1. However, as time elapses after the lead 1 is implanted, the lead 1 is covered with a fibrous film and adheres to a blood vessel wall or a heart cavity. Eventually, it will be completely fixed without the endocardial fixing means 42. Therefore, if the endocardial fixation means 42 is made of a biocompatible material which decomposes after a predetermined period in the living body as in the present invention, the endocardial fixation means 42 fixes the lead 1 When the role of the lead 1 becomes unnecessary, it does not melt and does not become an obstacle when removing the lead 1.

Specific examples of the biodegradable material constituting the endocardium fixing means 42 include proteins such as collagen, gelatin and fibrinogen, homopolymers such as lactic acid, glycolic acid and hydroxybutyric acid, and copolymers thereof. Aliphatic polyesters, polycarbonates such as polyethylene carbonate and polypropylene carbonate, polyorthoesters, polyamic acids such as poly-L-alanine and poly-γ-benzyl-L-glutamic acid, and hyaluronic acid esters. These polymers may be used alone or as a copolymer or a mixture of two or more kinds. Lactic acid also includes both optically active substances and racemic forms. Further, an elastic body may be obtained by blending a modifier with these polymers. For example, in this embodiment, DL-lactic acid (50 mol
%) And glycolic acid (50 mol%). In the immersion test in a phosphate buffer solution (pH 7.38) at 37 ° C., the strength and molecular weight of the material used in this embodiment gradually decreased from about one week after the start of the test. The strength was remarkably reduced, and at the sixth week, it was almost dissolved and the initial shape was not retained. It is needless to say that the mechanical characteristics and the decomposition characteristics of the endocardial fixation means 42 can be arbitrarily manipulated by changing the combination and composition of the above-mentioned materials.

In the lead having the above-described structure, a stylet 60 having a total length capable of being inserted to the distal end 4a of the lead 1 is inserted through the opening 8 and the stylet 6 is inserted.
The configuration is such that the leading end 60 a of the “0” can reach the groove 33 c of the electrode support 33.

The lead 1 having the above structure can fulfill a predetermined function.

FIG. 3 shows a case where the lead 1 has been used for a long time. As the lead 1 is used, the area around the lead 1 is firmly covered with the fibrous cap S, and at the same time, the endocardial fixation means 42 made of the above-mentioned biodegradable material is used in the body. Dissolve. As a result, conventionally, when removing lead 1 due to infectious disease or pacing failure,
Conversely, the endocardial fixation means 42 such as a tine provided with the obstructing protrusion (anchoring portion 42c) is already melted as shown in FIG. 3 if a predetermined period has elapsed after the lead 1 was implanted. Therefore, the endocardial fixation means 42 does not hinder the removal. That is, it is possible to remove the lead 1 as it is. The above-mentioned predetermined period differs depending on the material of the endocardial fixation means 42.

When the fibrous film covering the screw portion 34a of the electrode insulator 34 is strong, the electrode block 32 is connected to the tube 5
What is necessary is just to pull in to 0 and 51, and to remove. A method of drawing the related electrode block 32 into the tubes 50 and 51 will be described with reference to FIG.

Remove lead 1 from the pacemaker,
The stylet 60 is inserted through the opening 8. With the lead 1 firmly fixed by the tissue S, the tip 60a of the stylet 60 is engaged with the groove 33b, and the stylet is rotated from the opening 8 side in the direction of arrow D shown in the drawing. By the above operation, the threaded portion of the related electrode block 32, that is, the threaded portion 34a of the electrode insulator 34 moves in the direction of arrow A in the figure and is drawn into the tubes 50 and 51. It is needless to say that the stylet 60 is not limited to the above-described configuration, and various types that can be remotely operated can be used. For example, in the present embodiment, the tip portion 60a is
c to form a projection that engages with
The torque obtained by rotating “0” can be reliably transmitted to the related electrode block 32.

Also, when the day after the implantation of the lead is short and the endocardial fixation means 42 is not sufficiently dissolved, it is necessary to remove the lead 1 for some reason. The method will be described with reference to FIG.

That is, as shown in FIG. 5, in order to detach the endocardial fixation means 42 covered with the fibrous cap S, the lead 1 is removed from the pacemaker and the opening 8
The stylet 60 is inserted. Endocardial fixation means 42
Is firmly fixed with the tissue S, and the stylet 60
Is engaged with the groove 33c, and is rotated from the opening 8 side in the direction of arrow D shown in the figure. With the above operation, the electrode block 32 moves in the direction of arrow A in the figure, and the tube 50,
51, the endocardial fixation means 42 is detached from the lead body 4.

Further, since the endocardial fixation means 42, which remains in the body as it is, is a biodegradable material as described above, it is dissolved over time, so that it has no adverse effect on the living body. It has no effect and does not cause impaired blood flow. In addition, there is an advantage that even a lead that causes infection up to the endocardial fixation means is easily cured because the source of infection is small and disappears over time.

As an example of clinical application, when the day after the implantation of the lead 1 is shallow, the lead 1
When it becomes necessary to remove the lead, a
The lead end 4b of the lead body 4 is pulled out, and the stylet 6 is opened through the opening 8 of the lead proximal end 4b as shown in FIG.
0 is inserted into the lead 1, and the endocardial fixation means 42 is detached by the above-mentioned rotation operation. At this time, the endocardial fixation means 4
2 is firmly covered by the fibrous coating S and does not follow the rotation of the related electrode block 32, so that the related electrode block 32 can be stored inside the tubes 50 and 51.

After the endocardial fixation means 42 is detached in this way, the straight or tapered lead 1
Is relatively easy to remove intravenously. If the lead body 4 is completely adhered to the blood vessel wall or the heart chamber, the lead body 4 should be removed using a commonly used guiding sheath while peeling the adhered portion. Can be. Since the endocardial means 42 remaining in the living body is made of a biodegradable material as described above, it will melt after a predetermined period, so there is no problem.

As shown in FIG. 3, when a predetermined period of time has elapsed after the lead 1 has been implanted, the endocardial fixation means 42 has already been dissolved, so that the electrode block 32 is connected to the tube 50, Even if it is not pulled into 51, it can be removed as it is. When the fibrous film covering the screw portion 34a of the electrode insulator 34 is strong, the related electrode block 32 may be pulled into the tubes 50 and 51 as shown in FIG. The above-mentioned predetermined period varies depending on the material of the endocardial fixation means 42.

As described above, conventionally, it is extremely difficult to remove a lead intravenously. However, in the lead 1 according to the present invention, the endocardial fixing means 42 is made of a biodegradable material. Therefore, for example, even when a period of 5 years or more has elapsed after the lead implantation, the endocardial fixation means 42 has already been dissolved, and the transvenous withdrawal of the lead 1 can be easily performed. In addition, the lead 1 according to the present invention has a stylet 60
, The endocardial fixation means 42 is detachable by remote control, so that the endocardial fixation means 42 is melted, but the related electrode block 32 is covered with the strong fibrous cap S. In some cases, transvenous withdrawal is simple. When the endocardial fixation means 42 is not yet sufficiently dissolved, the lead 1 of the present invention is used as described above.
2 is configured to be removable, so that transvenous withdrawal is easy.

[Second Embodiment] FIG. 6A is a cross-sectional view of a main part showing the structure of a lead 1 according to a second embodiment, and FIG. FIG. 9 is a cross-sectional view of a main part showing a state in which the straight or tapered lead 1 is extracted intravenously after the lead 1 has been made. In this figure, the components already described with reference to FIGS. 1 to 5 are denoted by the same reference numerals, and description thereof will be omitted.

The electrode support 36 is formed with a hole 33k that fits into the tip 12c of the conductor coil 12. As shown in FIG. 6A, when the lead 1 is used in a living body, the electrode insulator 37 having a screw portion and the electrode portion 2 protrude from the end surface 14c of the insulating film 14. The electrode insulator 37 is firmly fixed with an adhesive or the like so as to cover the outer periphery on the distal side of the electrode support 36, and constitutes the related electrode block 35. At the lead distal end 4a, the related electrode block 35 is mechanically and electrically connected to the conductor coil 12, and is also mechanically connected to the insulating film 14 by using an adhesive or the like. The thread portion of the electrode insulator 37 on the distal side of the related electrode block 35 is provided with an endocardial fixing means 42 made of a biodegradable insulating material in a threaded state. The materials constituting the endocardial fixing means 42, the electrode block 32, the lead body 4 and the like are the same as those in the first embodiment.

Immediately after the lead 1 configured as described above is implanted, that is, since the endocardial fixation means 42 is not sufficiently dissolved, there is a possibility that the lead 1 may be obstructed. . In such a case, in order to remove the lead 1, the endocardial fixing means 42 may be detached in the living body as shown in FIG. 6 (b). First, in a state where the endocardial fixation means 42 is firmly fixed with the tissue S, the lead proximal end 4b in FIG. Then, this rotational force is transmitted to the lead distal end 4a via the lead body 4 of the lead 1, and the related electrode block 35 also rotates at the same time. At this time, since the endocardial fixation means 42 is covered with the tissue S, it does not follow the rotation of the electrode block 35. Therefore, by the above operation, the screwed state of the endocardial fixing means 42 is released, and the endocardial fixing means 42 is detached from the lead 1. As in the first embodiment, the remaining endocardial fixing means 42 dissolves and disappears after a predetermined period, so that there is no problem.

A predetermined period has passed since the lead 1 constructed as described above was implanted, and the endocardial fixation means 4
When 2 is sufficiently dissolved, the lead 1 can be removed as it is.

As an example of clinical application of this embodiment, when it is necessary to remove the lead 1 just after the lead 1 has been implanted for some reason, the proximal end 4b is exposed to the outside by skin incision. The lead body 4 is detached from the endocardial fixing means 42 by pulling out and rotating the lead. At this time, the endocardial fixation means 42 is covered with the fibrous cap S and does not follow the rotation of the interelectrode block 35 fixed integrally with the lead body 4, so that it can be detached. After being detached in this manner, the straight or tapered lead 1 is withdrawn intravenously. If the lead body 4 is adhered to the blood vessel wall or the heart cavity, the adhesion portion is peeled off in advance using a commonly used guiding sheath, and then the rotating operation is performed. It is desirable to add and remove.

As described above, when it is necessary to remove the lead due to an infection or pacing failure shortly after the lead is implanted, the heart covered with the fibrous cap at the tip of the lead can be easily operated. The lead can be withdrawn by releasing the intima fixing means. Also, after the lead is removed, the endocardial fixation means will remain in the heart chamber, but the size of the endocardial fixation means is very small, and will dissolve and disappear over time. Therefore, there is almost no adverse effect on the living body, and it does not cause blood flow inhibition. In addition, there is an advantage that even a lead that causes infection up to the endocardial fixation means is easily cured because the source of infection is small and disappears over time. In the lead according to the present invention, since the endocardial fixation means is made of a biodegradable material, the endocardial fixation means is already dissolved even when, for example, a period of 5 years or more has elapsed after lead implantation. Intravenous withdrawal of the lead is easy.

[0054]

As described above, according to the present invention,
Shortly after the lead is implanted, if it becomes necessary to remove the lead due to infection or pacing failure, simply remove the endocardial fixation means covered by the fibrous cap at the tip of the lead by simple operation. , The lead can be withdrawn. Also, after the lead is removed, the endocardial fixation means will remain in the heart chamber, but the size of the endocardial fixation means is very small, and will dissolve and disappear over time. So there is almost no adverse effect on the body,
Also, it does not cause blood flow inhibition. In addition, there is an advantage that even a lead that causes infection up to the endocardial fixation means is easily cured because the source of infection is small and disappears over time.

In the lead according to the present invention, since the endocardial fixation means is made of a biodegradable material, the endocardial fixation means remains intact even when a period of five years or more has passed after the lead implantation. It is already dissolved and transvenous withdrawal of the lead is easy. In addition, the lead according to the present invention has a configuration in which the endocardial fixation means can be removed by remote control of the stylet, so that the endocardial fixation means is dissolved, but the related electrode block has a strong fibrous cap. Intravenous withdrawal is easy, even when covered. Also, if the endocardial fixation means is not yet fully dissolved,
Since the lead of the present invention has such a structure that the endocardial fixation means can be removed as described above, transvenous withdrawal is easy.

[Brief description of the drawings]

FIG. 1 is an external perspective view showing an overall configuration of a lead 1 according to a first embodiment that can be implanted in a living body.

FIG. 2A is a cross-sectional view of a main part of a lead body 4 according to the first embodiment.

FIG. 2B is an enlarged cross-sectional view of a lead body distal end 4a according to the first embodiment.

FIG. 3 is a cross-sectional view of a main part of a lead body 4 for explaining a method of extracting a lead 1 according to the first embodiment.

FIG. 4 is a sectional view of a main part of a lead body 4 for explaining another method of extracting the lead 1 in the first embodiment.

FIG. 5 is a cross-sectional view of a main part of the lead body 4 for explaining a method of removing the lead 1 immediately after the lead 1 is implanted in a living body in the first embodiment.

FIG. 6A is a sectional view of a main part of a lead body 4 according to a second embodiment which can be implanted in a living body. (B) It is principal part sectional drawing of the lead body 4 in 2nd Embodiment for demonstrating the method of removing the lead 1 just after the lead 1 is implanted in the living body.

7 (a), (b), (c) are external perspective views of conventional general passive endocardial fixation means.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lead 2 Electrode part 4 Lead body 8 Opening 12 Conductor coil (electric conductor) 14 Insulating coating 32, 35 Related electrode block 33, 36 Electrode support 34, 37 Electrode insulator 42 Endocardial fixing means 50, 51 Tube 60 Stylet

Claims (5)

[Claims] 1. A lead for implanting a living body, comprising: a lead body for transmitting an electric signal generated by a device for implanting a living body; and at least one electrode for transmitting an electric signal transmitted from the lead body to a myocardium, A connecting means for mechanically and electrically connecting the living body implanting device to the first end of the lead body; an electrode provided at one end; and an energizable support connected to the lead body An insulating portion covering a part of an outer periphery of the support; and a second end of the lead body covering at least a part of an outer periphery of the insulating portion to fix the electrode to an endocardium. An endocardial fixation means made of a biodegradable material, which is detachably attached to the vicinity of the part, provided at a second end of the lead body, wherein the outer periphery of the lead body is biocompatible Biological implantable lead, characterized in that it is at least composed of an electrical conductor having a flexible covered with an insulating material. 2. The living body implanting lead further comprises:
A first tubular body that is mechanically fixed to the electrical conductor and has an electrically conductive first screw hole covered with the biocompatible insulating material; and a first tubular body. A second tube having a second threaded hole that is in contact with, is covered with the biocompatible insulating material, and is formed of the insulating material. The support has a screw portion that is screwed with the first and second screw holes, and the insulating portion includes the first, second, and third screws. A screw portion that is screwed into the hole portion, wherein the support is formed by rotating a stylet inserted through an opening formed on a first end side of the lead body; In order to release the threaded state of the hole and allow the insulating portion and the support to be accommodated in the first and second tubes, The lead for implanting a living body according to claim 1, further comprising an engaging portion that engages with the stylet. 3. The endocardial fixation means has a screw hole on the inside, the insulating part has a screw part screwed with the screw hole, and 2. The lead according to claim 1, wherein the threaded state of the screw portion is released from the screw hole by rotating the lead body. 3. 4. The lead for implanting a living body according to claim 1, wherein the endocardial fixation means forms a tine, a fin, and a flange-like mooring portion. 5. The biodegradable material is a material selected from the group consisting of proteins, aliphatic polyesters, polycarbonates, polyorthoesters, polyamic acids, and hyaluronic esters, or two or more materials selected from the group. The lead for implanting a living body according to any one of claims 1 to 4, wherein the lead comprises a copolymer or a mixture of materials to be used.