JP4955154B2 - Balloon catheter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a balloon catheter used for blocking blood flow, dilating a stenosis, and the like.
[0002]
[Background Art and Problems to be Solved by the Invention]
Conventionally, a balloon catheter having a structure in which a balloon is provided on the outer periphery of a human body insertion portion of a catheter shaft is known.
This type of balloon catheter is used in various applications such as blocking blood flow and dilating a stenosis. In any application, it is desirable to hold the balloon in an appropriate indwelling position during use. It is.
[0003]
However, the conventional balloon catheter has a structure in which the axial displacement of the catheter shaft is easily transmitted to the balloon, and when the catheter shaft is displaced in the axial direction at the proximal end, the distal end of the catheter shaft remains as it is. Since it is displaced in the axial direction and the balloon is displaced along with the displacement, it is not easy to maintain the state where the balloon is placed at an appropriate position.
[0004]
Further, in a balloon catheter used as an ascending aorta occlusion catheter for blocking blood flow in the ascending aorta during cardiac surgery, the myocardium released from the catheter to the vicinity of the coronary ostium by the blood flow received from the heart-lung machine The balloon may be displaced from an appropriate indwelling position due to the injection pressure of the protective liquid.
[0005]
The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a balloon catheter that can easily maintain a state where the balloon is placed at an appropriate position.
[0006]
The features of the present invention made to achieve the above object will be described in detail below .
[0014]
The balloon catheter of the present invention is
A catheter shaft having one or more lumens including at least a first lumen formed therein, and an outer periphery of a human body insertion portion of the catheter shaft, and the fluid inside is supplied and discharged through the first lumen. A balloon catheter with a balloon that expands / contracts with
The balloon has a shape having a recess on the outer surface at least when expanded, and is joined to the catheter shaft in the recess, and the balloon is at least partially constricted at the time of expansion. It is joined to the catheter shaft at the constricted portion,
A second lumen is formed inside the catheter shaft;
A side opening that communicates the outside of the catheter shaft and the second lumen is provided at the constricted portion at a position that does not overlap the concave portion of the balloon on the side surface of the human body insertion portion of the catheter shaft, By supplying the chemical solution to the second lumen, the chemical solution can be released from the side opening.
[0015]
In this balloon catheter, the concave portion of the balloon is a portion that is recessed toward the inside of the balloon, and the catheter shaft is joined to the balloon in the recess. Such a recess may be formed in advance when the balloon is molded, or by forming the balloon with a material that flexibly expands and contracts, the balloon expands in the axial direction of the catheter shaft when the balloon is expanded. Accordingly, a recess may be formed in the catheter shaft. When such a recess is provided, for example, if the catheter shaft is slightly displaced in the axial direction, the recess is deformed so that the recess is inflated to the outside of the balloon following the displacement of the catheter shaft. Since only the catheter shaft can be displaced without being displaced, it is possible to easily maintain the state where the balloon is placed at an appropriate position.
[0016]
When such a recess is formed on the distal end side of the balloon, it has a high effect of absorbing the displacement of the catheter shaft when the catheter shaft is displaced in the direction of being pushed into the blood vessel. Further, when the concave portion is formed on the proximal end side of the balloon, the effect of absorbing the displacement of the catheter shaft is high when the catheter shaft is displaced in the direction of being pulled out from the blood vessel. Therefore, when such a recess is formed at both ends of the balloon, both when the catheter shaft is displaced in the direction of being pushed into the blood vessel and when the catheter shaft is displaced in the direction of being pulled out of the blood vessel, This is particularly desirable because it can absorb the displacement of the catheter shaft.
[0017]
Further, a second lumen is formed inside the catheter shaft, and a side opening that communicates the outside of the catheter shaft and the second lumen is provided on a side surface of a human body insertion portion of the catheter shaft, By supplying the chemical liquid to the lumen, the chemical liquid can be released from the side opening . In that case, in particular, the side opening is provided at a position that does not overlap with the concave portion of the balloon, and when the catheter shaft is displaced relative to the balloon, the balloon membrane is moved to the side opening. Will not cause a situation that would block .
[0020]
Said balloon catheter, said balloon, that have at least when expanded to be comprised as one central constricted shape, a balloon is bonded to the catheter shaft in the constricted portion.
[0021]
In this balloon catheter, when the balloon is inserted at a substantially right angle with respect to the blood vessel, the balloon is symmetrically supported on the blood vessel wall around the catheter shaft, and is stably placed in the blood vessel. Therefore, even when a force is applied to the balloon inflated in the blood vessel, the balloon is stably placed without being displaced. In addition, the above-described effects can be maintained even if the balloon shape is reduced.
[0022]
Further, in this balloon catheter, a side opening that communicates the outside of the catheter shaft and the second lumen is provided at a constricted position of the balloon on the side surface of the catheter shaft, and supplies a chemical solution to the second lumen. By doing so, you may comprise so that a chemical | medical solution can be discharge | released from the said side surface opening part.
[0023]
Moreover, in this balloon catheter, the human body insertion portion of the catheter shaft may be reinforced with a reinforcing member.
In this balloon catheter, since the human body insertion portion of the catheter shaft is reinforced by the reinforcing member, even when blood flow is received from the heart-lung machine, the balloon is stably placed without being displaced.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment of the present invention will be described with an example.
The balloon catheter described below is used to block blood flow in the ascending aorta when performing cardiac surgery (an ascending aorta occlusion catheter).
[0025]
First Embodiment As shown in FIG. 1, the balloon catheter 1 includes a catheter shaft 3, a balloon 5, a first connector 7, a second connector 8, a tie cushion 11, and the like.
[0026]
The catheter shaft 3 is made of polyurethane and has a first lumen 15 and a second lumen 17 that are independent of each other, as shown in FIG.
One end of the first lumen 15 communicates with the first connector 7 via the first auxiliary tube 7a (see FIG. 1), and the other end communicates with an expansion fluid supply / discharge port 21 formed inside the balloon 5. The expansion liquid (physiological saline, etc.) supplied from the first connector 7 side is used to guide the inside of the balloon 5. The at least one expansion fluid supply / discharge port 21 is preferably provided in a region adjacent to the joint between the balloon 5 and the catheter shaft 3. The reason is that before the catheter is inserted, the operation of filling the balloon 5 with the expansion liquid and removing the bubbles is performed. However, if the supply / discharge port 21 is provided in the region adjacent to the joint as described above, the bubbles It is because it becomes easy to come off. In addition, in order to improve visibility and to easily guide the bubbles to the supply / discharge port 21, it is preferable to color the periphery of the supply / discharge port 21 (for example, black).
[0027]
One end of the second lumen 17 communicates with the second connector 8 via the second auxiliary tube 8a (see FIG. 1), and the other end of the second lumen 17 is in a distal end opening 23 formed at the distal end of the catheter shaft 3. A side opening 25 that communicates with the outside of the catheter shaft 3 and the second lumen 17 is provided on the proximal end side of the balloon 5. The second lumen 17 is used for passing the guide wire W through the portion from the distal end opening 23 to the side opening 25. Further, a portion from the side opening 25 to the second connector 8 is used to guide a medicine (myocardial protective solution or the like) injected from the second connector 8 side to the side opening 25, and further, the side opening It is also used for measuring 25 external blood pressures with a pressure sensor (not shown) connected to the second connector 8.
[0028]
Inside the second lumen 17, a valve 27 formed of an elastic body having rubber elasticity (silicone rubber in the present embodiment) is provided. The valve 27 has an insertion hole through which the guide wire W is passed. At least when the guide wire W is not passed through the insertion hole, the insertion hole is in a sealed state as shown in FIG. Therefore, the passage of fluid is blocked. Thereby, when the medicine is injected into the second lumen 17 from the second connector 8 side, the medicine is prevented from leaking from the distal end opening 23 and all the medicine is released from the side opening 25. can do. When the guide wire W is passed through the insertion hole, when the guide wire W is strongly pressed against the insertion hole, the valve 27 is elastically deformed by the force from the guide wire W and expands with the elastic deformation. The guide wire W is passed through the insertion hole.
[0029]
The balloon 5 is a bag formed of a polyurethane thin film (in this embodiment, a film thickness of 75 μm), and has a size that can block the ascending aorta when expanded. When the balloon 5 is made of polyurethane, there is an effect that it is less likely to be deformed than a balloon made of a rubber material when expanded. Concave portions 31 and 32 that are recessed toward the inside of the balloon 5 are formed at both ends of the balloon 5 to have an apple-like shape. These concave portions 31 and 32 are formed by making the distance between the joint portions shorter than the entire length of the balloon 5 when joining both ends of the balloon 5 to the catheter shaft 3.
[0030]
As shown in FIG. 3A, these recesses 31 and 32 are formed when the balloon 5 is expanded at an appropriate indwelling position in the blood vessel V, and then the catheter shaft 3 is displaced for some reason. As shown in (b), the concave portion 31 is inflated and at the same time the concave portion 32 is deformed so as to increase the depression, thereby preventing the balloon 5 from being displaced following the catheter shaft 3. In addition, even when the catheter shaft 3 is displaced in the direction opposite to the above, as shown in FIG. 3C, the concave portion 32 is inflated, and at the same time, the concave portion 31 is deformed so as to increase the depression, so that the balloon 5 is Displacement following the catheter shaft 3 is prevented.
[0031]
The tie cushion 11 is a cylindrical member for preventing the catheter shaft 3 from being adversely affected by an external force when a nelaton tube (not shown) is tied to the catheter shaft 3 and fixed to the catheter shaft 3.
Next, a usage example of the balloon catheter 1 will be described.
[0032]
First, the chest is incised to expose the ascending aorta, and the insertion site on the ascending aorta is perforated. Then, the guide wire W is inserted to establish the insertion route, and the hole is expanded by the dilator along the guide wire W.
Subsequently, the balloon catheter 1 is inserted into the ascending aorta along the guide wire W, and the balloon 5 is placed at an appropriate position while confirming the position of the balloon 5 by X-ray fluoroscopy. At this time, the second lumen 17 in the catheter shaft 3 is used as a guide wire insertion lumen.
[0033]
Then, the balloon 5 is expanded by removing the guide wire W and supplying an expansion liquid via the first lumen 15. As a result, ascending aorta Q is blocked by balloon 5 as shown in FIG. It is confirmed by angiography that the blood flow is blocked.
[0034]
Further, by supplying a myocardial protective solution through the second lumen 17 as necessary, the myocardial protective solution is released from the side opening 25 (shown by an arrow in FIG. 4), and the myocardial protective solution is provided near the coronary artery opening R A liquid can be administered. At this time, the second lumen 17 is used as a lumen for supplying a chemical solution. Further, the second lumen 17 is also used when measuring the blood pressure outside the side opening 25 with a pressure sensor connected to the second connector 8.
[0035]
As described above, according to the balloon catheter 1, by providing the valve 27, the second lumen 17 can be used for three purposes: guide wire insertion, drug solution supply, and blood pressure measurement. . Therefore, the diameter of the catheter shaft 3 can be reduced and the flexibility of the catheter shaft 3 can be increased as compared with a catheter shaft that is independently provided with lumens corresponding to these applications. Accordingly, the displacement on the proximal end side of the catheter shaft 3 is not easily transmitted to the distal end side, and the balloon 5 does not deviate from the proper indwelling position when the proximal end side of the catheter shaft 3 is slightly displaced. .
[0036]
Further, according to the balloon catheter 1, since the concave portions 31 and 32 are provided in the balloon 5, the displacement of the catheter shaft 3 can be absorbed by deforming the concave portions 31 and 32. Therefore, even when the displacement at the proximal end side of the catheter shaft 3 is transmitted to the distal end side, the displacement at the distal end side of the catheter shaft 3 is not easily transmitted to the central portion of the balloon 5, and As long as the end side is slightly displaced, the balloon 5 does not come off the proper indwelling position.
[0037]
As mentioned above, although embodiment of this invention was described, this invention is not limited to said specific one Embodiment, In addition, it can implement with a various form.
For example, in the balloon catheter 1, the valve 27 is provided on the catheter shaft 3 and the recesses 31 and 32 are provided on the balloon 5. However, the catheter 27 is provided with the valve 27 to reduce the diameter of the catheter shaft 3. As shown in the figure, the effect of maintaining the balloon 5 in the proper indwelling position can be obtained without providing the concave portions 31 and 32 in the balloon 5.
[0038]
On the contrary, if the concave portions 31 and 32 are provided in the balloon 5, the effect of maintaining the balloon 5 in an appropriate indwelling position can be obtained without providing the valve 27 on the catheter shaft 3. In this case, if not necessary, the guide wire insertion lumen itself may be eliminated, and a balloon catheter of a type that is inserted without using the guide wire may be used. In this case, the balloon 5 is provided with the recesses 31 and 32. Thus, the effect of maintaining the balloon 5 at an appropriate indwelling position can be obtained accordingly.
[0039]
In this case, in order to improve the indwelling stability of the catheter, as shown in FIG. 5 (a) or FIG. 5 (b), a linear metal wire 222 or a spiral reinforcement is provided on the catheter shaft 203 of the balloon catheter 201. It is preferable to incorporate the material 223. As the material of the metal wire 222, an elastic material such as nickel / titanium alloy or stainless steel alloy (JIS standard SUS304 or the like) is used, and an inelastic material such as stainless steel alloy (SUS316) or copper or the like is used. As the spiral reinforcing member 223, in addition to the same material as the metal wire 222, a resin having a hardness higher than that of the material of the catheter shaft is used. The lengths of the metal wire 222 and the spiral reinforcing member 223 may be any length from the distal end of the catheter shaft 203, but preferably have a length in the range of 5 cm to 20 cm.
[0040]
When the metal wire 222 is incorporated, the shape of the catheter shaft is set to a constant outer diameter from the distal end to the middle part (a portion beyond the proximal side fixed by the tie cushion), and from the middle part. The proximal end side may have a tapered structure in which the outer diameter gradually decreases. If such a structure is adopted, the catheter is bent at a boundary portion between the support portion and the wire that supports or holds the metal wire and the bending strength of the catheter is a concern. Kink) can be effectively avoided.
[0041]
Instead of the linear metal wire 222 and the spiral reinforcing member 223, a metal pipe, a flat metal plate, or a solid metal cylinder may be used. Such an example is shown in FIGS. 6 (a) to 6 (d). In FIG. 6A, a metal pipe 224 is built in a lumen 219 for blood pressure measurement. The metal pipe 224 functions to reinforce the distal end portion of the catheter shaft, and is used for blood pressure measurement by allowing liquid to pass therethrough. In the example shown in FIG. 6B, the metal plate 225 is built in the partition wall 220 that separates the first lumen 215, the third lumen 219, and the second lumen 217.
[0042]
In the example shown in FIG. 6C, a metal pipe 226 is built in the partition wall 220. In the example shown in FIG. 6D, a solid metal cylinder 227 is built in the partition wall 220.
In the above embodiment, by providing the side opening 25, the second lumen 17 is also used for guide wire insertion, drug supply, and blood pressure measurement. For example, a contrast agent is used for contrasting the catheter shaft 3. If the second lumen 17 is used for the purpose of filling, the side opening 25 may be omitted. Even when such a configuration is adopted, the guide wire insertion and the contrast medium filling lumen can be used together. Therefore, by reducing the diameter of the catheter shaft 3, the effect of maintaining the balloon 5 in an appropriate indwelling position can be obtained. Obtainable.
[0043]
Furthermore, in the said embodiment, although the guide wire W was derived | led-out from the side surface opening part 25, the structure through which the guide wire W is passed over the full length of the catheter shaft 3 may be employ | adopted. In this case, since the side opening 25 may have a structure that does not allow the guide wire W to pass therethrough, a large number of openings having a small opening area may be provided.
[0044]
If such a large number of openings are provided, each opening can be formed in a different direction, so even if one opening is sealed by the blood vessel wall, The chemical solution can be reliably released. Of course, when a large number of openings are provided, the guide wire W may be inserted into some of the openings.
[0045]
Although the balloon catheter 1 has been described as being used when blocking blood flow in the ascending aorta, the balloon catheter adopting the configuration of the present invention is used when blocking blood flow in blood vessels other than the ascending aorta. Even if is used, the effect that the balloon can be maintained at an appropriate indwelling position can be obtained. In addition to blocking blood flow, for example, when a balloon catheter is used to perform dilatation treatment for a vascular stenosis, if the balloon catheter employing the configuration of the present invention is used, the balloon is maintained at an appropriate indwelling position. As a result, the effect of the expansion treatment can be further ensured.
[0046]
Second Embodiment In this embodiment, as shown in FIGS. 7 (a) and 7 (b), a catheter shaft at a position where a side opening 325 for releasing a drug corresponds to a substantially central portion of the balloon 305 is used. 303. As in the first embodiment, the balloon 305 has recesses 331 and 332 on the outer surface when expanded, and is configured such that a portion 333 of the central portion is constricted. The balloon 305 is joined to the catheter shaft 303 in the recess. A side opening 325 that communicates the outside of the catheter shaft 303 and the second lumen 317 (see FIG. 8) is provided at the constricted position. Since other configurations are the same as those of the first embodiment, description thereof will be omitted.
[0047]
As schematically shown in FIG. 8, the occlusion catheter of this embodiment is inserted into the ascending artery Q as in the first embodiment, and the expansion fluid is injected into the balloon 305 from the expansion fluid supply / exhaust port 321. Is expanded. When the balloon 305 is expanded, the balloon 305 is fixed to the blood vessel wall by the compression force of the balloon. In particular, as shown in FIG. 8, when the catheter shaft 303 is inserted substantially at right angles to the blood vessel, the front and back of the catheter shaft 303 are supported symmetrically by the balloon, so that the stability is good.
[0048]
Therefore, even when the pressure PP indicated by the arrow in FIG. 8 is applied to the artery opposite to the heart connected to the heart-lung machine, the indwelling position of the balloon 305 does not fluctuate and high indwelling stability is achieved. Secured. In this state, the myocardial protective solution is injected near the coronary artery opening R through the side opening 325. Similarly, when the injection pressure of the myocardial protective solution becomes too high, the indwelling stability of the balloon is ensured.
[0049]
FIG. 8 shows a state in which the occlusion catheter is inserted at a substantially right angle with respect to the ascending artery. As shown in FIGS. 9A and 9B, the occlusion catheter is inclined with respect to the ascending artery. Even when the balloon is inserted, the total contact area between the balloon 305 and the blood vessel wall does not fluctuate and has sufficient compression force, so that the placement stability of the balloon is ensured.
[0050]
FIG. 10A shows an occlusion catheter having a balloon 405 that is entirely spherical except for the constricted portion 433. The balloon 405 shown in FIG. 10A is a spherical member 405a shown in FIG. 10B before being attached to the catheter shaft 403. The spherical member 405a has fixing portions 405b and 405c fixed to the catheter shaft 403 at both ends. The fixing portion 405b attached to the distal end of the catheter shaft 403 is folded inward and joined to the catheter shaft 403, and the other fixing portion 405c is joined to the catheter shaft 403 as it is. As shown in FIG. 10, the myocardial protective solution can be supplied through a side opening 425 formed in the catheter shaft 403. Further, the occlusion catheter shown in FIG. 10 can obtain the same indwelling stability as shown in FIG.
[0051]
In the embodiments described so far, the chest is incised to expose the ascending aorta and the occlusion catheter is inserted, but the chest incision need not be performed. For example, an occlusion catheter may be inserted into the ascending aorta by opening a hole in the chest so that the ascending aorta can be accessed from the outside.
[Brief description of the drawings]
FIG. 1 is a side view of a balloon catheter described as a first embodiment of the present invention.
FIG. 2 is a cross-sectional end view of the vicinity of the balloon of the balloon catheter.
FIGS. 3A and 3B are diagrams illustrating a deformed state of a concave portion provided in a balloon, wherein FIG. 3A is an explanatory diagram illustrating an undeformed state, FIG. 3B is an explanatory diagram illustrating a state in which one concave portion is inflated; ) Is an explanatory view showing a state in which the other concave portion is swollen.
FIG. 4 is a schematic diagram showing a use state of a balloon catheter.
FIGS. 5A and 5B are schematic views showing a balloon catheter in which a human body insertion portion is reinforced, in which FIG. 5A shows a case where it is reinforced with a linear metal wire, and FIG. 5B shows a case where it is reinforced with a spiral reinforcing material. FIG.
FIG. 6 is a cross-sectional view showing a modification of the reinforcing member, (a) is a view showing a case where a metal pipe is built in a lumen for blood pressure measurement, and (b) is a metal in a partition wall separating each lumen. It is a figure which shows the case where a board is built, (c) is a figure which shows the case where a metal pipe is built in a partition, (d) is the case where a solid metal cylinder is built in a partition. FIG.
7A and 7B are views showing a balloon catheter according to a second embodiment, wherein FIG. 7A is a front view of the vicinity of the balloon, and FIG. 7B is a top view thereof.
FIG. 8 is a schematic view showing a use state of the balloon catheter of the second embodiment.
FIG. 9 is a schematic view for explaining the indwelling state of the balloon in the second embodiment, (a) is a view showing a state where the catheter shaft is slightly inclined with respect to the blood vessel, and (b) is a view It is a figure which shows the state inclined further.
FIG. 10 is a schematic view showing a modification of the second embodiment, (a) is a view showing a balloon catheter, and (b) is a view showing a balloon used for the catheter shown in (a). is there.
[Explanation of symbols]
1, 201 ... Balloon catheter, 3, 203, 303, 403 ... Catheter shaft, 5, 205, 305, 405 ... Balloon, 7 ... First connector, 7a ... First auxiliary tube , 8 ... 2nd connector, 8a ... 2nd auxiliary tube, 11 ... Tie cushion, 15, 215, 315 ... 1st lumen, 17, 217, 317 ... 2nd lumen, 21 ... Expansion fluid supply / discharge port, 23 ... Distal end opening, 25, 325, 425 ... Side opening, 27 ... Valve, 31, 32, 331, 332 ... Recess, 222 ... Metal wire, 223 ... Spiral reinforcement, 224, 226 ... Metal pipe, 225 ... Metal plate, 227 ... Metal cylinder

Claims (3)

A catheter shaft having one or more lumens including at least a first lumen formed therein, and an outer periphery of a human body insertion portion of the catheter shaft, and the fluid inside is supplied and discharged through the first lumen. A balloon catheter with a balloon that expands / contracts with
The balloon has a shape having a recess on the outer surface at least when expanded, and is joined to the catheter shaft in the recess, and the balloon is at least partially constricted at the time of expansion. It is joined to the catheter shaft at the constricted portion,
A second lumen is formed inside the catheter shaft;
A side opening that communicates the outside of the catheter shaft and the second lumen is provided at the constricted portion at a position that does not overlap the concave portion of the balloon on the side surface of the human body insertion portion of the catheter shaft, A balloon catheter characterized in that a chemical solution can be released from the side opening by supplying a chemical solution to the second lumen.   The balloon catheter according to claim 1, wherein the recess is formed at both ends of the balloon.   The balloon catheter according to claim 1 or 2, wherein a human body insertion portion of the catheter shaft is reinforced.

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