JP2008054901A - Intravascular stiffener - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an intravascular stiffener easily inserted into a narrow blood vessel and easily recovered from the blood vessel. <P>SOLUTION: An embolization catheter 6A is passed into a blood vessel 4, an embolization coil 7 made of platinum is pushed out from the embolization catheter 6A indwelled in aneurysm 5, a protect coil is pushed out from a microcatheter 6 is pushed out, and a coil part 2 is placed in the blood vessel 4 of the aneurysm 5 with a large neck to separate the blood vessel 4 from the aneurysm 5. At this time, the embolization catheter 6A is positioned outside the coil part 2. A wire constituting the coil part 2 is so densely coiled as to come into contact with each other. The inside of the aneurysm 5 is tightly embolized by the embolization coil 7, and the embolization catheter 6A is removed by separating the embolization coil in the embolization catheter 6A from the embolization coil in the aneurysm 5. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an intravascular reinforcing tool. Specifically, the present invention relates to an intravascular reinforcing tool used in combination with an aneurysm occlusion device.

  One of the serious vascular diseases is an aneurysm, but many aneurysms are formed by the burden of blood flow on the crotch part at the vascular bifurcation, but once aneurysm is naturally reduced However, it has been reported that in many cases it increases by about 5 to 10% per year.

  There is a correlation between the diameter of the aneurysm and the risk of rupture. When the diameter is 5 to 6 mm, the risk of rupture is high, and the success rate of emergency surgery in the case of rupture is as low as about 50% even in specialized emergency hospitals. Therefore, it is very important to treat aneurysms before rupture.

On the other hand, for aneurysms, methods for medical treatment such as medication have not been established, and surgical treatment is common. In surgical treatment, embolization of cerebral aneurysms has made great progress with the advent of detachable coils (GDC, etc.).
Cerebral aneurysm embolization is a treatment that packs metal in the aneurysm without performing craniotomy, and is another treatment alongside clipping for cerebral aneurysms that cause subarachnoid hemorrhage . In other words, a thin tube is advanced from the blood vessel at the base of the leg to the cerebral aneurysm, and a platinum coil is packed in the aneurysm.

However, problems remain with wide neck aneurysms, aneurysms that branch off from aneurysms, dissecting aneurysms, small aneurysms, and giant aneurysms.
Here, in a small aneurysm, there is a high risk of perforation when a catheter is inserted into the aneurysm.
In a wide neck aneurysm, the coil may deviate from the aneurysm to the parent vessel. In addition, a balloon catheter is used as a method to compensate for embolization of a wide neck aneurysm, and there is a method of preventing deviation of the coil with the balloon, but there is a drawback of closing the blood flow with the balloon, increasing the risk of cerebral overflow and thrombus formation To do.

  In addition, there is an example in which an intracranial stent is used together in order to prevent deviation of the coil, but it is not easy to reach a hard stent into the skull, and there are limited examples of success.

  Therefore, in order to avoid the possibility of unnecessary trauma or damage to the blood vessel, a device that is used in combination with a blood vessel occlusion device installed in the aneurysm to occlude the aneurysm has been proposed (for example, Patent Document 1). reference.). FIG. 6 is a schematic diagram for explaining a conventional intravascular device. However, Patent Document 1 discloses a columnar intravascular device 110 configured as a series of circumferential loops 112 connected by a connecting portion 114 in a longitudinal direction. In this configuration of the intravascular device 110, the free ends of the wire are parallel to each other and formed in a pair of circumferential portions 112, and the transition to the pair of parallel elements 114 is the second An end loop that extends in a semicircular arc until reaching a position formed during distance 118, but the parallel element transitions back to another pair of circumferential loops 112 before forming the end of the stent. Continuous toward 120. With such a configuration, the region in the vicinity of the aneurysm can be reinforced.

Japanese translation of PCT publication No. 2002-52088

However, in the conventional intravascular device, the free ends of the wire are parallel to each other and formed in a pair of circumferential portions, and parallel elements (longitudinal connecting portions) are also paired. In order to pass the inner device through the catheter, two parallel wires must be bundled into one, so that the diameter of the catheter is limited to a large one. In addition, the conventional intravascular device is not suitable for a blood vessel having a diameter of 1 to 2 mm because it includes a circumferential portion and parallel elements and has a complicated shape.
Moreover, since the conventional intravascular device is provided with a pair of longitudinal connection portions, the opening of the side wall is large, and hemostasis using the side wall cannot be performed. Moreover, since the conventional intravascular device is provided with a circumferential loop, when the intravascular device is recovered from within the blood vessel, there is a possibility that it cannot be recovered due to entanglement with the coil in the aneurysm.

  The present invention has been devised in view of the above points, and an object thereof is to provide an intravascular reinforcing tool that can be inserted into a thin blood vessel and can be easily recovered from the blood vessel.

  In order to achieve the above object, an intravascular reinforcing tool according to the present invention is disposed in a catheter inserted into a blood vessel, and is composed of a strand having an outer diameter substantially the same as the inner diameter of the catheter. In the reinforcing tool, the strand pushed out from the catheter forms a coil portion, and the outer diameter of the coil portion is substantially the same as the inner diameter of the blood vessel.

  Here, since it is comprised with the strand which has an outer diameter substantially the same as the internal diameter of a catheter, when a strand is put in a catheter, it will become one line shape. Further, since the outer diameter of the coil portion is substantially the same as the inner diameter of the blood vessel to be inserted, it is possible to suppress the filling from deviating from the aneurysm and entering the blood vessel.

  Further, in the intravascular reinforcing device of the present invention, when the coil portion is made of a shape memory material, for example, even if the shape is changed by being inserted into a catheter or the like, the shape is immediately restored when it is taken out from the catheter or the like. be able to.

  In addition, in the intravascular reinforcing tool of the present invention, when both ends of the coil portion are opened, the coil portion can be put out from the other end through another instrument into the coil portion while being placed in the blood vessel. . In addition, if the annular bodies of the strands constituting the coil portion are in close contact with each other, the blood flow in the side wall direction of the coil portion is attenuated, and the inflow of blood flow into the aneurysm is suppressed. Aneurysm rupture can be suppressed. Therefore, application to dissecting aneurysms, small aneurysms, and giant aneurysms is expected.

  In the intravascular reinforcing tool of the present invention, the first annular body of the coil portion and the second annular body adjacent to the first annular body are arranged at a predetermined interval, and the coil portion When the diameter of the coil portion is sequentially reduced from one end to the other end, the coil portion serves as a filter, and the thrombus that has been released can be collected without closing the blood flow.

  The intravascular reinforcing tool according to the present invention can be inserted into a thin blood vessel and can be easily recovered from the blood vessel.

Hereinafter, embodiments of the present invention will be described with reference to the drawings to facilitate understanding of the present invention. FIG. 1 is a schematic view for explaining the structure of a protect coil which is an intravascular reinforcing tool to which the present invention is applied.
In the first embodiment of the protect coil shown in FIG. 1 (a), the protect coil 1 is composed of one elastic wire made of a shape memory alloy (nickel titanium alloy) and both ends are opened. And a delivery wire 3 made of a linear shape memory alloy (nickel titanium alloy) connected to the coil portion 2. Moreover, the outer diameter of the coil part 2 is substantially the same as the inner diameter of the blood vessel to be inserted. Here, the wire which comprises the coil part 2 is so dense that it contacts mutually.
Further, in the second mode of the protect coil shown in FIG. 1B, the diameter of the coil portion 2 is reduced gradually from one end of the coil portion 2 to which the delivery wire 3 is connected toward the other end. The first embodiment is the same as the first embodiment except for the conical shape.

  Here, if the outer diameter of the coil portion is substantially the same as the inner diameter of the blood vessel to be inserted, the coil portion does not necessarily have to be composed of a wire made of nickel titanium alloy, such as stainless steel, superelastic alloy, You may be comprised with the material containing platinum or these combination.

FIG. 2 is a schematic diagram illustrating a procedure for embolizing a wide neck aneurysm using the protect coil of the present invention. First, the platinum embolization coil 7 is pushed out from the embolization catheter 6A placed in the aneurysm 5 through the embolization catheter 6A in the blood vessel (parent vessel) 4, and the protection coil of the present invention is pushed out from the microcatheter 6. The coil portion 2 is placed on the blood vessel (parent blood vessel) 4 of the wide neck aneurysm 5 to separate the blood vessel 4 and the aneurysm 5 (see FIG. 2A). At this time, the embolic catheter 6 </ b> A is located outside the coil portion 2. Here, the wire which comprises the coil part 2 is so dense that it contacts mutually.
Next, the aneurysm 5 is tightly embolized by the embolization coil 7, and the embolization coil in the embolization catheter 6A and the embolization coil in the aneurysm 5 are separated to remove the embolization catheter 6A (FIG. 2). (See (b).)
And the delivery wire 3 is pulled, the coil part 2 is accommodated in the microcatheter 6, and it removes from the body (refer FIG.2 (c)). When the embolization coil 7 is likely to deviate outside the aneurysm 5, i.e., to enter the blood vessel 4, the coil portion 2 and the delivery wire 3 are electrolyzed and the coil portion 2 is separated from the blood vessel 4. Leave in.

  FIG. 3 is a schematic diagram illustrating a procedure for reinforcing the inner wall of a dissociated blood vessel using the protect coil of the present invention. 3A shows a blood vessel 4 in which a dissecting aneurysm 5 is formed and an inner wall is dissociated. As shown in FIG. 3B, the coil portion 2 is pushed out from the microcatheter 6 to dissociate the aneurysm. 5 and the blood vessel 4 are separated and the inner wall of the blood vessel 4 is reinforced. Here, the wires constituting the coil portion 2 are in contact with each other, and the invasion of blood flow into the aneurysm 5 is suppressed. And the coil part 2 and the delivery wire 3 are isolate | separated, and the coil part 2 is detained in the blood vessel 4 (refer FIG.3 (c)).

FIG. 4 is a schematic diagram illustrating a state in which a blood vessel in which a giant aneurysm is generated is reinforced using the protect coil of the present invention. In the case of a giant aneurysm, the intravascular embolization often does not heal and blocks the parent blood vessel from the aneurysm.
Here, a microcatheter (not shown) is inserted into the blood vessel 4, the microcatheter (not shown) is pushed to a position beyond the aneurysm 5, and the coil portion 2 is pushed out from the microcatheter (not shown). Then, the microcatheter (not shown) is pulled back, and the coil portion 2 is placed in the blood vessel 4 so that the blood vessel 4 and the aneurysm 5 are separated by the coil portion 2 of the protect coil. Here, the wires constituting the coil portion 2 are so dense that they come into contact with each other, and the blood flow into the aneurysm 5 is suppressed.

  FIG. 5 is a schematic diagram for explaining a state in which free thrombus is collected using the protect coil of the present invention. The site where the thrombus 9 is generated in the blood vessel 4 becomes a stenosis part and blood does not flow easily. Therefore, a stent 8 which is a mesh metal tube is placed in the stenosis part to improve the blood flow. However, when the stent 8 is placed in the stenosis, the thrombus 9 scatters to become a free thrombus, and if this free thrombus is left unoccupied, the blood vessel is closed again. The conical coil part 2 in which the diameter of the coil part 2 is successively reduced is placed on the periphery of the blood vessel to collect the free thrombus.

As described above, the intravascular reinforcing tool of the present invention is composed of a strand having an outer diameter that is substantially the same as the inner diameter of the catheter. It can be inserted into a thin blood vessel of ˜2 mm and can be easily recovered from the blood vessel.
Moreover, since a coil part changes to one linear form, when collect | recovering a coil part from the blood vessel, possibility that it will get entangled with the embolic coil in an aneurysm reduces.
Further, since the outer diameter of the coil portion is substantially the same as the inner diameter of the blood vessel to be inserted, it is possible to suppress the filling from deviating from the aneurysm and entering the blood vessel.

  In addition, since the coil portion is made of a shape memory material, even if it is inserted into a catheter or the like and the shape is changed, it can be immediately returned to the stored shape when it is taken out from the catheter or the like.

  Moreover, since both ends of the coil portion are open, the coil portion can be put out from the other end through another device into the coil portion from one end of the coil portion while the coil portion is indwelled in the blood vessel.

  In addition, the first annular body of the coil portion and the second annular body adjacent to the first annular body are arranged at a predetermined interval, and from one end of the coil portion to the other end, Since the diameter of the coil portion is gradually reduced, the coil portion serves as a filter, and the thrombus and the like that have been released can be collected without closing the blood flow.

It is the schematic explaining the structure of the protect coil which is an intravascular reinforcement tool to which this invention is applied. It is the schematic explaining the procedure of embolizing a wide neck aneurysm using the protect coil of this invention. It is the schematic explaining the procedure which reinforces the inner wall of the dissociated blood vessel using the protect coil of this invention. It is the schematic explaining the state which reinforced the blood vessel which the giant aneurysm produced using the protect coil of the present invention. It is the schematic explaining the state which collect | recovers free thrombus using the protect coil of this invention. It is the schematic explaining the conventional intravascular apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Protect coil 2 Coil part 3 Delivery wire 4 Blood vessel 5 Aneurysm 6 Microcatheter 6A Embolization catheter 7 Embolization coil 8 Stent 9 Thrombus

Claims (4)

An intravascular reinforcing tool that is arranged in a catheter that is inserted into a blood vessel, and is composed of a strand having an outer diameter substantially the same as the inner diameter of the catheter,
The wire pushed out from the catheter forms a coil part,
The outer diameter of the coil portion is substantially the same as the inner diameter of the blood vessel. The intravascular reinforcement device according to claim 1, wherein the coil portion is made of a shape memory material. The both ends of the said coil part were open | released. The intravascular reinforcement tool of Claim 1 or Claim 2 characterized by the above-mentioned. The first annular body of the coil portion and a second annular body adjacent to the first annular body are arranged at a predetermined interval and from one end of the coil portion toward the other end. The diameter of the said coil part reduced sequentially, The intravascular reinforcement tool of Claim 1 or Claim 2 characterized by the above-mentioned.

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