JP5101025B2 - Thrombus aspiration catheter - Google Patents

Description

  The present invention relates to an improvement in an aspiration catheter that is introduced into a body percutaneously and transcutaneously, and sucks and removes a thrombus generated in a blood vessel in the body or a foreign substance released in the blood vessel.

A thrombus aspiration catheter is used to remove clots clogged in blood vessels, but in order to aspirate a large amount of thrombus, the amount of aspiration is increased and the catheter is broken during aspiration to prevent it from being aspirated. A difficult catheter is needed.
In particular, since the thrombus aspiration catheter is guided to the affected part through the inside of the guiding catheter, blood vessel followability and kink resistance are required.
In order to increase the suction volume, it is important to increase the inner diameter of the shaft tube. However, since the distal part requires a lumen through which the guide wire passes, it is necessary to increase the cross-sectional area of the suction lumen. is there.

For example, in Patent Document 1, the tip of the main shaft (corresponding to the shaft tube) is cut obliquely, and the tip of the guide wire shaft (corresponding to the guide wire tube) is located at the most distal portion of the main shaft, or The length from the proximal end of the guide wire shaft to the most distal end of the main shaft is L1, the length of the main shaft that is obliquely cut from the distal end of the guide wire shaft. The invention of the suction catheter is described in which 0.5 ≦ L2 / L1 and L2−L1 ≦ 5 mm with respect to the length L2.
The catheter has a length in the longitudinal direction of the catheter at a portion where the main shaft is cut obliquely, L1, and a length L2 from the proximal end of the guide wire shaft to the end of the main shaft is 0.5 ≦ L2 / By defining L1 and L2-L1 ≦ 5 mm, the blood vessel followability is improved, but the length of the double lumen (the overlapping portion of the main shaft and the guide wire shaft) consisting of the guide wire lumen and the suction lumen is Since it is short and has a maximum of only 15 mm, further improvement in blood vessel followability and kink resistance is required.
Patent Document 2 discloses an invention in which a cross-sectional area of an injection lumen of a drug or the like is increased in a catheter for local injection of a drug or the like.

JP 2004-65326 (Claims, FIGS. 1 to 5) Special table 10-500028 (Fig. 12)

  The problem to be solved by the present invention is that blood vessel followability and kink resistance are insufficient.

[1] In the present invention, the shaft tube (2) is formed from three types of tubes having different hardnesses in the proximal portion (3), the intermediate portion (4), and the distal portion (5) . The tube connects the same resin material by thermal welding,
A braid is attached to the inner wall surface of the proximal portion (3) as a reinforcing material (7) so as not to come in contact with the liquid, whereby the proximal portion (3) is formed by a braided tube,
A suction lumen (11) over the proximal part (3), the intermediate part (4) and the distal part (5);
Wherein the distal portion (5) is fitted with a guide wire tube (6), thereby the distal portion (5) has a double lumen structure to have a guide wire lumen (10) and the aspiration lumen (11) Have
The suction lumen (11) is provided between the proximal portion (3) formed by the braided tube and the distal portion (5) of the double lumen structure to which the guide wire tube (6) is attached. Place the middle part (4),
The length of the guide wire lumen (10) of the distal portion (5) of the double lumen structure : GL is formed from 80 mm to 120 mm,
The length of the intermediate part (4); ML is formed from 50 mm to 150 mm,
The intermediate part (4) is formed with a Shore D hardness of 60 to 72, and the distal part (5) of the double lumen structure is formed with a Shore D hardness of 30 to 45,
When the hardness of the intermediate portion (4): D1 is 100, the distal portion (5) of the double lumen structure is formed of a soft tube having a D2 of 42 to 75,
A thrombus aspiration catheter (1) is provided.
[2] The present invention is the a suction lumen (11) is shaped substantially the arcuate shape of the inside sectional area of the cross-sectional area of the aspiration lumen (11) (S1) is a shaft tube (2) (S2) The thrombus aspiration catheter (1) according to [1], which is formed in 85% or more of the above.
[3] In the present invention, the distal portion (5) is formed of two or more types of tubes having different hardnesses, the distal end side is formed of a soft tube (16), and the proximal end side is the distal end side. A thrombus aspiration catheter (1) according to [1] or [ 2 ], which is formed of a stiffer tube (15).

(1) When the hardness D1 of the intermediate portion 4 is 100, the hardness D2 of the distal portion 5 is formed of a soft tube of 40 to 75, so that the reach distance to the meandering blood vessel can be improved. Moreover, the insertion resistance to the meandering blood vessel is low, and the permeability to the meandering blood vessel can be improved.
(2) The shaft tube 2 is formed of three types of tubes having different hardnesses, the distal portion 5 is formed of a tube softer than the intermediate portion 4, and the length of the guide wire lumen 10 of the distal portion 5: GL is 50 mm. From 200 mm to the length of the intermediate part 4; By forming the ML from 30 mm to 200 mm, the guide wire lumen 10 formed long can absorb the vibration at the time of catheter insertion, and the long intermediate part 4 interferes. Therefore, blood vessel followability and kink resistance can be improved.
(3) By setting the cross-sectional area S of the suction lumen 11 to 80% or more of the lumen cross-sectional area of the shaft tube 2, the suction amount can be improved.

FIG. 1 is a schematic view of a thrombus aspiration catheter 1 of the present invention. 2 is an enlarged view of the vicinity of the distal portion 5 in FIG. 1, FIG. 3 is a cross-sectional view taken along the line AA ′ in FIG. 1, and FIG. 4 is a cross-sectional view taken along the line BB ′ in FIG.
[Shaft tube 2]
In the thrombus aspiration catheter 1 of the present invention, the shaft tube 2 is formed of three types of tubes having different hardnesses of the proximal portion 3, the intermediate portion 4 and the distal portion 5.
[Proximal part 3]
Since it is most important that the tube constituting the proximal portion 3 is not broken, a reinforcing material 7 such as a braid made of metal or synthetic resin is attached to the inner wall surface of the proximal portion 3 so as not to come into contact with the liquid. Has been.
The proximal portion 3 is preferably a “braided tube” that is flexible and less likely to break than a highly rigid stainless steel tube or polyimide tube.
The “braided tube” is a tube in which a braid made of metal, synthetic resin or the like is embedded in the inner wall surface of a synthetic resin tube so as not to come into contact with liquid.
The synthetic resin tube may be a single layer, two layers, or three layers. In the case of two layers, a braid embedded between the inner layer and the outer layer is used. In the case of three layers, a braid is wound around the inner layer and an intermediate layer and an outer layer are laminated.
As preferable examples of the “braided tube” of the present invention, inner layer: PE, polyamide, polyamide elastomer, fluororesin, etc. Braid: stainless steel wire (50-30 micron), synthetic fiber such as nylon fiber, outer layer: polyamide, polyamide elastomer PE, urethane, etc. are used. Furthermore, when arrange | positioning an intermediate | middle layer, polyolefin which has adhesiveness in an inner layer and an outer layer is used.
The proximal part 3 has a suction lumen 11.

[Distal part 5]
The distal portion 5 is preferably made of a soft material as compared with the intermediate portion 4 in order to improve the blood vessel permeability of the catheter. For example, the hardness D1 of the intermediate portion 4 to 100 (Shore D hardness 60 to 72), the hardness D2 of the distal portion 5, is good to the 4 2 to 75 (Shore D hardness 30 to 45).
If the hardness D2 is too small (hardness D1; less than 40 with respect to 100), it is too soft and the blood vessel permeability of the catheter is reduced. If it is too large (hardness D1; more than 75 with respect to 100), This is not preferable because the insertion resistance increases.
Moreover, you may form the distal part 5 with two or more types of tubes from which hardness differs as needed. In this case, it is preferable that the distal end side is formed of a soft tube 16 and the proximal end side is formed of a hard tube 15. The tube of the distal portion 5 has a soft tip and a hard base end side reduces blood vessel damage and makes the tube difficult to break.
A guide wire tube 6 is attached to the distal portion 5. As shown in FIG. 2 (sectional view), the distal portion 5 and the guide wire tube 6 are mounted so as to be circular as a whole.
The distal portion 5 has a guide wire lumen 10 and a suction lumen 11.
[Intermediate part 4]
The length of the intermediate part 4 connecting the distal part 5 and the proximal part 3; ML may be 30 mm to 200 mm, preferably 50 to 120 mm. When the length is too long, the catheter is easily broken, and when the length is too short, the proximal portion 3 (braided tube) hits the guiding catheter curved portion, and the passing property is deteriorated. The intermediate part 4 has a suction lumen 11.
[Guide wire lumen 10]
The length of the guide wire lumen 10; GL is preferably from 50 mm to 200 mm, and preferably from 80 to 120 mm, in order to improve the adhesion between the catheter and the guide wire.
If the length is too long, the passage of the guide wire is deteriorated. If the length is too short, the guide wire and the shaft tube 2 are separated from each other, and the blood vessel followability is deteriorated.

[Suction lumen 11]
In order to increase the amount of suction, it is necessary to increase the cross-sectional area S of the suction lumen 11 at the distal portion, but not only to increase the cross-sectional area but also to increase according to the outer diameter of the shaft tube 2. There is a need.
For example, in the shape illustrated in FIG. 2 (guide wire lumen 10; circular), when the shaft 2 is 6 Fr (inner diameter: 1.10 mm, cross-sectional area S2; 0.95 mm ² ), the longest diameter of the suction lumen 11: 1.24 mm In the case of 0.426 mm, the cross-sectional area S1 of the suction lumen 11 is 0.93 mm ² .
When the shaft 2 is 7Fr (inner diameter: 1.32 mm, cross-sectional area S2: 1.37 mm ² ), the longest diameter of the suction lumen 11: 1.40 mm, and the guide wire lumen 10 has a diameter of 0.426 mm, the suction lumen 11 The cross-sectional area S1 is 1.19 mm ² .
Thus, it is important to bring the sectional area S1 of the suction lumen 11 close to the sectional area S2 of the inner diameter of the shaft 2, and the sectional area S1 of the suction lumen 11 is 80% or more of the sectional area S2 of the inner diameter of the shaft 2, preferably 85% or more is desirable.
[Tube material]
Moreover, polyamide, polyamide elastomer, PE, urethane, etc. are used for the constituent material of the tube of the distal part 5 and the intermediate part 4. FIG.
Since the respective tubes (proximal part 3, intermediate part 4, and distal part 5) are thermally welded, it is desirable to use the same resin.
As preferable examples of the “braided tube” of the present invention, inner layer: PE, polyamide, polyamide elastomer, fluororesin, etc. Braid: stainless steel wire (50 to 30 micron), synthetic fiber such as nylon fiber, outer layer: polyamide, polyamide elastomer PE, urethane, etc. are used. Furthermore, when arrange | positioning an intermediate | middle layer, polyolefin which has adhesiveness in an inner layer and an outer layer is used.

表１の結果より、本発明の実施例１から３のほうが、比較例１から２よりも押出しの抵抗、引き戻し時の抵抗が小さいため、ＰＴＣＡガイディングカテーテルの通過性の点で優れていることが確認できた。
（２）シャフトチューブ２の近位部３を構成するチューブ抗キンク性試験
実施例４、５として、編組チューブ、比較例３、４として、ポリイミド製チューブを使用した。
編組チューブとして、内層：ポリアミドエラストマー、編組（中間）：ステンレス線（５０マイクロ）、外層：ポリアミドエラストマーを使用した。
各チューブを一定の長さ（８４ｍｍ）に切り取り、チューブをＵ字状に曲げ、チューブの両端をゆっくりと近づけていく時、チューブ中央部が折れたときの両端の距離を測定した。

表２より、比較例のポリイミド製チューブより、編組チューブのほうが、折れにくいことが確認された。
（３）模擬蛇行血管へのカテーテル到達距離の比較
実施例６として、中間部４をショアーＤ硬度６３Ｄのポリアミドエラストマーで形成し、遠位部５をショアーＤ硬度４０Ｄのポリアミドエラストマーで形成した図１の形態を有する７Ｆｒの血栓吸引カテーテルを使用した。また、実施例７として、中間部４をそれぞれショアーＤ硬度７０Ｄのポリアミドエラストマーで形成し、遠位部５をショアーＤ硬度４０Ｄのポリアミドエラストマーで形成した実施例６と同形状の血栓吸引カテーテルを使用した。比較例５として現在既上市品の中で最も評価の高いＡ社製品を使用し、比較評価試験を実施した。模擬蛇行血管として、ポリアセタール製の半径１５ｍｍの連続した円弧形状を有する模擬蛇行血管モデルを使用した。

表３の結果より市場で評価が高いＡ社製品と比較して本実施例６、７は、３〜６％蛇行血管への到達距離が長く、蛇行血管への通過性が優れていることが確認できた。
通常血栓吸引カテーテル等では、蛇行血管への到達距離を１ｍｍでも長くすることがユーザーより要望されているが、本発明では、現行の最優良製品よりも、何と４から７ｍｍも到達距離を伸ばすことに成功した。
（４）模擬蛇行血管へのカテーテルの挿入抵抗の比較
実施例８として、中間部４をショアーＤ硬度６３Ｄのポリアミドエラストマーで形成し、遠位部５をショアーＤ硬度４０Ｄのポリアミドエラストマーで形成した図１の形態を有する７Ｆｒの血栓吸引カテーテルを使用した。
比較例６として、中間部４を６３Ｄのポリアミドエラストマーで形成し、遠位部５をショアーＤ硬度５５Ｄのポリアミドエラストマーで形成した実施例１と同形状の血栓吸引カテーテルを使用した。

表４より、本発明の実施例１の方が比較例１よりも模擬蛇行血管への挿入抵抗が低く、蛇行血管への通過性が優れていることが確認できた。 Next, examples of the present invention and comparative examples are shown.
(1) Measurement of resistance value when passing through guiding catheter As Examples 1 to 3, a 6Fr thrombus aspiration catheter having the intermediate portion 4 (length; ML is 50 to 150 mm) in FIG. 1 was used.
As Comparative Examples 1 and 2, a 6Fr thrombus aspiration catheter having the intermediate portion 4 in FIG. 1 and the intermediate portion 4 (length; ML is 10 mm) was used.
The resistance when passing through the PTCA guiding catheter was passed through the PTCA guiding catheter JL4.0 (manufactured by Kawasumi Chemical Co., Ltd.) through the suction catheter of the example and the comparative example, and the thrombus suction catheter was extruded 100 mm from the tip of the PTCA guiding catheter. The load at the time and the load at which the thrombus aspiration catheter extruded 100 mm was returned to the PTCA guiding catheter were measured.

From the results shown in Table 1, Examples 1 to 3 of the present invention are superior in terms of passage of the PTCA guiding catheter because the resistance to extrusion and the resistance at the time of pulling back are smaller than those of Comparative Examples 1 to 2. Was confirmed.
(2) Tube anti-kink property test constituting the proximal portion 3 of the shaft tube 2 As Examples 4 and 5, a braided tube and Comparative Examples 3 and 4 were polyimide tubes.
As the braided tube, inner layer: polyamide elastomer, braided (intermediate): stainless steel wire (50 micro), outer layer: polyamide elastomer were used.
Each tube was cut into a fixed length (84 mm), the tube was bent into a U shape, and when the both ends of the tube were slowly brought closer together, the distance between the ends when the tube center part was broken was measured.

From Table 2, it was confirmed that the braided tube was less likely to break than the polyimide tube of the comparative example.
(3) Comparison of Catheter Reaching Distance to Simulated Serpentine Blood Vessel As Example 6, the intermediate portion 4 is formed of a polyamide elastomer with a Shore D hardness of 63D, and the distal portion 5 is formed of a polyamide elastomer with a Shore D hardness of 40D. A 7 Fr thrombus aspiration catheter having the following form was used. Further, as Example 7, a thrombus aspiration catheter having the same shape as Example 6 in which the intermediate part 4 is made of a polyamide elastomer having a Shore D hardness of 70D and the distal part 5 is made of a polyamide elastomer having a Shore D hardness of 40D is used. did. As Comparative Example 5, a comparative evaluation test was carried out using the product of Company A having the highest evaluation among currently marketed products. A simulated serpentine blood vessel model having a continuous arc shape with a radius of 15 mm made of polyacetal was used as the simulated serpentine blood vessel.

Compared with the products of Company A, which have a higher evaluation in the market than the results in Table 3, Examples 6 and 7 have a long reach to the meandering blood vessels of 3 to 6% and have excellent permeability to the meandering blood vessels. It could be confirmed.
In the case of a thrombus aspiration catheter or the like, the user is requested to increase the reach distance to the meandering blood vessel even by 1 mm, but in the present invention, the reach distance is extended by 4 to 7 mm more than the current best product. succeeded in.
(4) Comparison of insertion resistance of catheter into simulated meandering blood vessel As Example 8, intermediate part 4 is formed of polyamide elastomer with Shore D hardness 63D, and distal part 5 is formed of polyamide elastomer with Shore D hardness 40D A 7 Fr thrombus aspiration catheter having a configuration of 1 was used.
As Comparative Example 6, a thrombus aspiration catheter having the same shape as that of Example 1 in which the intermediate portion 4 was formed of a 63D polyamide elastomer and the distal portion 5 was formed of a polyamide elastomer having a Shore D hardness of 55D was used.

From Table 4, it was confirmed that Example 1 of the present invention had a lower insertion resistance to the simulated meandering blood vessel than Comparative Example 1, and was superior in permeability to the meandering blood vessel.

Schematic of the thrombus aspiration catheter of the present invention 1 is an enlarged view of the vicinity of the distal portion 5 AA 'sectional view of FIG. BB 'sectional view of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Thrombus suction catheter 2 Shaft tube 3 Proximal part 4 Middle part 5 Distal part 6 Guide wire tube 7 Reinforcement material 8 (Proximal part) Inner layer 9 (Proximal part) Outer layer 10 Guide wire lumen 11 Suction lumen 12 (Proximal) Part) Intermediate layer 15 Hard tube 16 Soft tube 18 Contrast marker 20 Connector 21 Connector cover

Claims (3)

The shaft tube (2) is formed from three types of tubes having different hardnesses in the proximal portion (3), the intermediate portion (4) and the distal portion (5), and the three types of tubes are made of the same resin material. Are connected by thermal welding,
A braid is attached to the inner wall surface of the proximal portion (3) as a reinforcing material (7) so as not to come in contact with the liquid, whereby the proximal portion (3) is formed by a braided tube,
A suction lumen (11) over the proximal part (3), the intermediate part (4) and the distal part (5);
Wherein the distal portion (5) is fitted with a guide wire tube (6), thereby the distal portion (5) has a double lumen structure to have a guide wire lumen (10) and the aspiration lumen (11) Have
The suction lumen (11) is provided between the proximal portion (3) formed by the braided tube and the distal portion (5) of the double lumen structure to which the guide wire tube (6) is attached. Place the middle part (4),
The length of the guide wire lumen (10) of the distal portion (5) of the double lumen structure : GL is formed from 80 mm to 120 mm,
The length of the intermediate part (4); ML is formed from 50 mm to 150 mm,
The intermediate part (4) is formed with a Shore D hardness of 60 to 72, and the distal part (5) of the double lumen structure is formed with a Shore D hardness of 30 to 45,
Thrombus aspiration catheter characterized in that when the hardness of the intermediate portion (4): D1 is 100, the distal portion (5) of the double lumen structure is formed of a soft tube having a D2 of 42 to 75 ( 1). The shape of the suction lumen (11) has a substantially segmental shape, the cross-sectional area of the aspiration lumen (11) (S1) is formed in more than 85% of the inside sectional area of said shaft tube (2) (S2) The thrombus aspiration catheter (1) according to claim 1, characterized by that.   The distal portion (5) is formed of two or more types of tubes having different hardness, the distal end side is formed of a soft tube (16), and the proximal end side is harder than the distal end side (15). The thrombus aspiration catheter (1) according to claim 1 or 2, wherein the thrombus aspiration catheter (1) is formed.

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