JP7854320B2 - Medical devices and balloon catheters - Google Patents

Description

This invention relates to medical devices and balloon catheters.

There is a need to control the shape of devices used to treat stenotic lesions in vivo (such as balloon catheters and stents; hereinafter referred to as "treatment devices"). The balloon catheter described in Patent Document 1 has a balloon and a tension wire. The tip of the tension wire is fixed near the tip of the balloon. A wire cover portion provided on the outer surface of the balloon covers the tension wire along its length. When the balloon is expanded and the tension wire is pulled towards the proximal end, the balloon curves such that the side with the wire cover portion faces the inner circumference, and the side opposite the wire cover portion faces the outer circumference.

Japanese Patent Publication No. 2019-146599

In the balloon catheter described above, the portion of the tension wire that is positioned along the balloon is completely covered by the wire cover. In this case, it may not be possible to significantly increase the curvature of the balloon by pulling the tension wire. Therefore, it may not be possible to meet requirements such as wanting to curve the balloon to a large degree. Thus, the balloon catheter described above has the problem that it cannot curve the balloon to the shape desired by the user.

The object of the present invention is to provide a medical device and a balloon catheter that can control a therapeutic device, including a balloon, to a desired shape within a living body.

A medical device according to a first aspect of the present invention comprises a main body assembly including at least a main body having a lumen; a plurality of guide members provided on the outer surface of the main body, each having a through hole and arranged at intervals in a first direction along the outer surface of the main body; and a string inserted through the through holes of each of the plurality of guide members and movable to one side or the other side in the first direction, characterized in that the main body deforms as the interval between each of the plurality of guide members in the first direction changes due to the movement of the string.

The medical device has multiple guide members on its main body, and the main body is deformed by changing the spacing between them using a string. Therefore, the medical device can bend its main body with a large curvature, allowing its shape to be deformed into a desired shape. Furthermore, when the main body is used to deform a treatment device within the body, the medical device can deform the shape of the treatment device into a desired shape.

In the first embodiment, the plurality of guide members comprises a plurality of first guide members whose spacing in the first direction is greater than a first threshold, and a plurality of second guide members whose spacing in the first direction is less than a second threshold, and the first threshold may be greater than the second threshold. Due to the movement of the string, the portion of the main body provided with the plurality of first guide members deforms more than the portion provided with the plurality of second guide members. Therefore, the medical device can be deformed into a desired shape by adjusting the positions of the plurality of first guide members and the plurality of second guide members in the main body.

In the first embodiment, the plurality of first guide members may be provided in the central part of the main body in the first direction, and the plurality of second guide members may be provided on one side of the main body relative to the plurality of first guide members in the first direction, and on the other side of the main body in the first direction. In this case, the central part of the main body in the first direction of the medical device can be deformed more significantly.

In the first embodiment, the plurality of guide members may be arranged at equal intervals in the first direction. In this case, the medical device can be uniformly deformed.

In the first embodiment, the plurality of guide members may include a plurality of third guide members aligned in the first direction, and a plurality of fourth guide members positioned at different locations in the circumferential direction around an axis extending along the center of the main body, relative to the plurality of third guide members, and aligned in the first direction. In this case, the medical device can deform the main body over a wide area in the circumferential direction.

In the first embodiment, the cord may be alternately inserted through the through holes of each of the plurality of third guide members and the through holes of each of the plurality of fourth guide members. In this case, the medical device can deform the main body by applying an even force to the plurality of third guide members and the plurality of fourth guide members corresponding to the movement of the cord.

In the first embodiment, when the plurality of guide members are cut in a plane perpendicular to the first direction, the cross-section may have a shape in which the end opposite the axis extending along the center of the main body is pointed. In this case, the medical device can treat by applying the pointed portions of each of the plurality of guide members to the affected area in the body.

In the first embodiment, one end of the cord may be connected to the main body assembly, and it may move in the first direction in response to a force acting on the other end. In this case, the medical device can deform the main body by applying the force used to move the cord to the main body assembly as well.

In the first embodiment, one end of the cord may be connected to the portion of the cord excluding the one end, and it may move in the first direction in response to a force acting on the other end. In this case, the amount of movement of the cord required to deform the main body of the medical device can be suppressed, allowing the main body to be deformed efficiently.

In the first embodiment, one end of the string may be movably connected to the portion of the string excluding the one end. In this case, the string can efficiently transmit the force acting on the other end to multiple guide members, thereby deforming the main body.

In the first embodiment, a protective film may be further provided between the main body and the cord. This allows the medical device to protect the main body from the cord.

In the first embodiment, the main body may be provided with an elastic body at a position different from the plurality of guide members in the circumferential direction around an axis extending along the center of the main body. In this case, the medical device can easily return the main body to its original shape after deformation due to the elastic force of the elastic body.

In the first embodiment, the device may further include a shaft connected to the main body, the shaft having a through-hole through which the cord is inserted. In this case, the medical device can prevent the cord from getting caught in the body and hindering its movement.

In the first embodiment, the medical device may further include a restricting member that restricts the movement of the cord along the first direction. In this case, the medical device can maintain the state after the cord has moved by the restricting member. Therefore, the medical device can maintain the state in which the main body has been deformed due to the movement of the cord.

In the first embodiment, the main body may have an expandable and contractible bag-like shape. In this case, when treating an affected area by expanding the main body, the medical device can deform the main body to a shape optimal for the affected area.

A balloon catheter according to a second aspect of the present invention comprises a balloon, a shaft to which the balloon is connected, a plurality of guide members provided on the outer surface of the balloon, each having a through hole and arranged at intervals along the longitudinal axis of the outer surface of the balloon, and a string inserted through the through holes of each of the plurality of guide members and movable to one or the other side in the longitudinal axis direction, characterized in that the balloon deforms as the interval between each of the plurality of guide members in the longitudinal axis direction changes when the string moves in the longitudinal axis direction.

In a second embodiment, the balloon catheter has multiple guide members provided on the balloon, and the balloon is deformed by changing the spacing between them using strings. Therefore, the balloon catheter can bend the balloon with a large curvature, allowing the balloon's shape to be deformed into a desired shape.

This is a diagram showing medical device 1A, and cross-sectional views of each part. This figure shows a balloon catheter 9. This diagram shows medical device 1A and balloon catheter 9 (with the string 4A not being pulled). This figure shows medical device 1A and balloon catheter 9 (with the string 4A pulled). This diagram shows the usage of medical device 1A and balloon catheter 9. This figure shows modified examples 1 to 3 of medical device 1A. This figure shows a modified example 4 of medical device 1A. This figure shows modified examples 5 and 6 of medical device 1A. This is a diagram of medical device 1B. This is a diagram showing medical device 1C. This is a diagram of medical device 1D. This is a diagram of medical device 1E. This is a diagram showing a balloon catheter 90.

<Overview of Medical Device 1>
An embodiment of the medical device 1 according to the present invention will be described with reference to the drawings. The drawings are used to illustrate the technical features that the present invention may adopt, and the configuration of the device etc. described is not intended to limit the invention to that, but is merely an illustrative example.

Balloon catheters are used to dilate stenotic lesions (hereinafter referred to as "stenotic lesions") formed in blood vessels, such as blood vessels, vas deferens, ductus faropiois, and lymphatic vessels, and to reperfuse the vessels.

Stenotic lesions that form in blood vessels often have complex structures, especially at bends. When treating stenotic lesions with a balloon catheter, it is desirable that the inflated balloon adequately conforms to the shape of the blood vessel. However, conventional balloon catheters often become straight when inflated. Therefore, it is structurally difficult to apply appropriate force to the entire inner wall of the stenotic lesion using the balloon. On the other hand, if a pre-curved balloon is inflated, a force trying to stretch the balloon acts on it. This can lead to areas in the stenotic lesion where excessive force from the balloon is applied. Furthermore, excessive force may be applied that deforms structures that fix the blood vessel (e.g., the pericardium in the case of coronary arteries, or the mesentery in the case of intestinal vessels). Additionally, the difficulty in accurately determining the bending angle of the blood vessel beforehand, and the inability to change the bending angle during treatment, make it difficult to predict the appropriate balloon catheter for a stenotic lesion in advance.

Furthermore, a method of repeatedly using a shortened balloon to dilate stenotic lesions is also known. However, in this case, the treatment time increases, increasing the burden on both the user (operator) and the patient. Also, repeatedly inflating and deflating the same balloon may damage the balloon catheter itself.

In contrast, the medical device 1 according to this embodiment allows for adjustment of the degree of curvature of the balloon 9B of the balloon catheter 9 according to the condition of the stenotic lesion. Therefore, the medical device 1 can effectively treat stenotic lesions with complex structures, particularly in the curved portions, using the balloon catheter 9.

<First Embodiment - Medical Device 1A>
As shown in Figure 1, the medical device 1A comprises a main body assembly 2A, guide members 31A, 32A, 33A, 34A, 35A, 36A, 37A, and 38A (hereinafter, when not distinguishing between them, they will be referred to as "guide member 3A"), a cord 4A, and a shaft 5A.

The main assembly 2A has a bag-shaped main body portion 20 that is elongated in a predetermined direction. The main body portion 20 is expandable and contractible. Figure 1 shows the main body portion 20 in an expanded state. A lumen 20L is formed inside the main body portion 20. Hereafter, unless otherwise specified, each part will be described assuming the main body portion 20 is in an expanded state. The predetermined direction is referred to as the "extension direction."

The main body 20 has a tip-side cone portion 21, an expansion portion 22, and a base-side cone portion 23. The expansion portion 22 has a cylindrical shape that extends in the stretching direction. The tip-side cone portion 21 extends from one end of the expansion portion 22 toward the opposite side of the expansion portion 22, while decreasing in diameter. The base-side cone portion 23 extends from the other end of the expansion portion 22 toward the opposite side of the expansion portion 22, while decreasing in diameter. Hereinafter, the side extending from the expansion portion 22 toward the tip-side cone portion 21 in the stretching direction will be referred to as the "tip side." The side extending from the expansion portion 22 toward the base-side cone portion 23 in the stretching direction will be referred to as the "base side." The imaginary axis extending through the center of the main body 20 will be referred to as the "central axis C11."

A circular through-hole 21H is formed in the tip of the front cone portion 21 (hereinafter referred to as "the tip portion 20D of the main body portion 20"). A circular through-hole 23H is formed in the base portion of the base cone portion 23 (hereinafter referred to as "the base portion 20P of the main body portion 20"). The direction extending along the outer surface of the main body portion 20 between the tip portion 20D and the base portion 20P is referred to as "the first direction D1".

The shaft 5A is a flexible tubular member. The shaft 5A extends in the extension direction between its tip 50D and its base 50P. The shaft 5A has a circular internal lumen 50L. The tip 50D of the shaft 5A connects to the base 20P of the main body 20 of the main body assembly 2A. The internal lumen 50L of the shaft 5A communicates with the internal lumen 20L of the main body 20 via a through-hole 23H. A hypothetical axis extending through the center of the shaft 5A is called the "central axis C12." The central axis C12 coincides with the central axis C11 of the main body 20.

The guide member 3A is provided on the outer surface of the main body portion 20 of the main body assembly 2A. The material of the guide member 3A is metal, hard resin, etc. The radially outer portion of the guide member 3A, centered on the central axis C11, is curved. A through hole 30H is formed in the guide member 3A, penetrating in the first direction D1. The cross-sectional shape of the through hole 30H is circular.

Guide member 31A is provided on the tip-side cone portion 21 of the main body portion 20. Guide member 38A is provided on the base-side cone portion 23 of the main body portion 20. Guide members 32A to 37A are provided on the expansion portion 22 of the main body portion 20. Guide members 31A to 38A are arranged in this order from the tip side to the base side in the first direction D1. The distance in the first direction D1 between guide member 3A and other guide members 3A adjacent to guide member 3A in the first direction D1 (hereinafter referred to as "distance between guide members 3A") is S11. Guide members 31A to 38A are arranged at equal intervals in the first direction D1.

The cord 4A has a flexible, elongated cord-like shape. The material of the cord 4A is suture thread, metal, resin, etc. The tip 40D of the cord 4A is connected to the vicinity of the through-hole 21H formed in the tip 20D of the main body 20 of the main body assembly 2A. The cord 4A extends along the first direction D1, sequentially passing through the through-holes 30H of the guide members 31A to 38A towards the base end. Furthermore, from the portion passing through the through-hole 30H of the guide member 38A, the cord 4A extends along the extension direction near the shaft 5A towards the base end 40P. The cross-sectional shape of the cord 4A is circular. The diameter of the cord 4A is smaller than the inner diameter of the through-hole 30H of the guide member 3A.

The cord 4A is movable in the first direction D1 relative to the guide members 31A to 38A in the portion that overlaps with the main assembly 2A in the stretching direction. Furthermore, the cord 4A is movable in the stretching direction relative to the shaft 5A in the portion that overlaps with the shaft 5A in the stretching direction.

Referring to Figure 2, the balloon catheter 9 will be described. The balloon catheter 9 is used while positioned inside the medical device 1A. The balloon catheter 9 has a catheter shaft 9A and a balloon 9B.

The catheter shaft 9A has an outer tube 91 and an inner tube 92. The outer tube 91 and the inner tube 92 are both flexible tubular members. The inner diameter of the outer tube 91 is larger than the outer diameter of the inner tube 92. The inner tube 92 is positioned within the lumen of the outer tube 91, except for a predetermined portion at the tip. A portion of the inner tube 92 at the tip protrudes from the tip of the outer tube 91 toward the tip. This portion of the inner tube 92 is positioned further forward than the tip of the outer tube 91. A guidewire W (see Figure 5) is inserted into the lumen of the inner tube 92. A fluid hub (not shown) is connected to the proximal end of the catheter shaft 9A.

Balloon 9B is connected to the tip of the catheter shaft 9A. The distal end of balloon 9B is connected to the tip of the inner tube 92. A portion of the inner tube 92, including its tip, protrudes further than the tip of balloon 9B. The proximal end of balloon 9B is connected to the tip of the outer tube 91. Balloon 9B covers a portion of the inner tube 92 that protrudes further than the outer tube 91.

The fluid hub supplies compressed fluid to the space within the lumen of the outer tube 91, excluding the lumen of the inner tube 92. In response to the supply of compressed fluid, the balloon 9B deforms from a contracted state to an expanded state. Figure 2 shows the balloon 9B in its expanded state.

The balloon 9B has a tip cone portion 93, an expansion portion 94, and a base cone portion 95. When the balloon 9B is inflated, the tip cone portion 93 extends from the connection point with the inner tube 92 toward the base end, expanding in diameter. The base cone portion 95 extends from the connection point with the outer tube 91 toward the tip end, expanding in diameter. The expansion portion 94 extends in the stretching direction between the base end of the tip cone portion 93 and the tip end of the base cone portion 95.

As shown in Figure 3, when the balloon catheter 9 is used together with the medical device 1A, the balloon 9B is positioned in the lumen 20L (see Figure 1) of the main body 20 of the main body assembly 2A of the medical device 1A. The portion of the inner tube 92 of the balloon catheter 9 that protrudes beyond the tip of the balloon 9B is inserted through a through-hole 21H provided in the tip 20D of the main body 20 of the medical device 1A, and is positioned outside the main body 20.

The catheter shaft 9A of the balloon catheter 9 is positioned in the lumen 50L (see Figure 1) of the shaft 5A of the medical device 1A. The catheter shaft 9A is inserted through a through-hole 23H provided in the proximal end 20P of the main body 20, extends toward the tip, and connects to the balloon 9B positioned in the lumen 20L of the main body 20.

Figure 3 shows the state in which no force is acting on the cord 4A of the medical device 1A. In this state, the main body 20 is extended in the stretching direction, and the gap S11 between the guide members 3A is maintained. In this case, no force acts from the main body 20 of the main body assembly 2A on the balloon 9B in a direction intersecting the central axis C11. Therefore, the shape of the inflated portion 94 of the inflated balloon 9B is extended in the stretching direction, similar to the shape when used alone.

Figure 4 shows the state in which a force is applied to the base end 40P of the cord 4A of the medical device 1A in a direction toward the base end. The cord 4A is pulled toward the base end and moves toward the base end. In this case, a force toward the base end is applied to the part of the main body 20 of the medical device 1A to which the tip 40D of the cord 4A is connected. Also, the cord 4A applies a force to the guide member 3A in a direction that causes it to move toward other guide members 3A adjacent to the first direction D1. The part of the main body 20 sandwiched between the part where the guide member 3A is provided and the part where other guide members 3A adjacent to this guide member 3A in the first direction D1 are provided will bend. The distance between the guide members 3A becomes S12, which is smaller than the distance S11 (see Figure 3) when no force is applied to the cord 4A of the medical device 1A.

As the spacing between the guide members 3A changes from spacing S11 to spacing S12, the length in the first direction D1 of the portion of the main body 20 where the guide members 3A are provided becomes smaller than the length in the first direction D1 of the portion located on the opposite side of the central axis C11 from the guide members 3A. As a result, the main body 20 deforms and curves. The guide members 31A to 38A are arranged at equal intervals in the first direction D1. Therefore, the main body 20 curves uniformly with approximately the same curvature from the tip portion 20D to the base portion 20P.

Furthermore, the curvature of the main body 20 changes according to the amount of movement when the string 4A is pulled. The curvature of the main body 20 is greater when the amount of movement of the string 4A is large than the curvature of the main body 20 when the amount of movement of the string 4A is small.

As the main body 20 deforms, the balloon 9B, positioned within the lumen 20L of the main body 20, receives a force from the main body 20 in a direction intersecting the central axis C11. As a result, the balloon 9B deforms and curves in accordance with the movement of the main body 20.

On the other hand, if the force acting on the base end 40P of the string 4A is released from the state shown in Figure 4, the main body 20 returns to its original state shown in Figure 3 due to a restoring force based on its own rigidity. The main body 20 becomes extended in the stretching direction. Furthermore, the balloon 9B positioned in the lumen 20L of the main body 20 also follows the main body 20, returning to its original state shown in Figure 3 and becoming extended in the stretching direction.

Referring to Figure 5, the method of using medical device 1A and balloon catheter 9 will be explained. An example will be given in which medical device 1A and balloon catheter 9 are used to dilate a portion of the blood vessel 8 that has been obstructed by a stenotic lesion 80 occurring on the inner wall of a bent section.

The user prepares medical device 1A with the balloon catheter 9 positioned inside. The balloon 9B is in a deflated state. The main body 20 of medical device 1A is in a deflated state due to its own elastic force. The user passes the guidewire W into the blood vessel 8. The user also positions the main body assembly 2A of medical device 1A and the balloon 9B of the balloon catheter 9 into the blood vessel 8. The guidewire W is inserted through the inner tube 92 of the balloon catheter 9.

The user pushes the shaft 5A of medical device 1A and the catheter shaft 9A of balloon catheter 9 into the blood vessel 8. This causes medical device 1A and balloon catheter 9 to move distally along the guidewire W towards the stenotic lesion 80 within the blood vessel 8. As shown in Figure 5A, when the main assembly 2A of medical device 1A and the balloon 9B of balloon catheter 9 reach the stenotic lesion 80, the user stops the movement of medical device 1A and balloon catheter 9.

Next, the user pulls the proximal end 40P (see Figure 1) of the cord 4A of the medical device 1A toward the proximal end. Simultaneously, the user operates the fluid hub to supply compressed fluid to the catheter shaft 9A of the balloon catheter 9. The balloon 9B expands from its deflated state to its expanded state. In response to the expansion of the balloon 9B, the main body 20 also expands. Since the cord 4A is being pulled toward the proximal end, the main body 20 bends, applying a force to the expanding balloon 9B in a direction intersecting the central axis C11 (see Figure 1). As a result, the balloon 9B deforms and bends in accordance with the main body 20.

As shown in Figure 5B, the curved, inflated balloon 9B contacts the stenotic lesion 80 in the bend of the blood vessel 8 from the inside and pushes it outwards. This expands the portion of the blood vessel 8 that is blocked by the stenotic lesion 80. The user adjusts the amount of movement of the cord 4A according to the condition of the bend in the blood vessel 8. This allows the balloon 9B to deform into the shape desired by the user, and the portion blocked by the stenotic lesion 80 is appropriately expanded.

Next, the user operates the fluid hub to remove the compressed fluid from balloon 9B. Balloon 9B deflates from its expanded state to its contracted state. The main body 20 also contracts due to its own elastic force in response to the contraction of balloon 9B. Simultaneously, the user releases the force applied to the string 4A. As a result, the main body 20 returns to its state before bending (see Figure 5C).

Next, the user manipulates the shaft 5A of medical device 1A and the catheter shaft 9A of balloon catheter 9 to move medical device 1A and balloon catheter 9 proximal and remove them from the body. Then, the user removes the guidewire W from the body.

<Operation and Effects of the First Embodiment>
As described above, the medical device 1A has guide members 3A provided on the main body 20. The spacing between the guide members 3A changes from spacing S11 to spacing S12 in response to the operation of pulling the string 4A toward the base end. As a result, the main body 20 deforms and curves. Therefore, the medical device 1A can curve the main body 20 with a larger curvature compared to, for example, the case where a single guide member is provided over the entire area of the main body 20 in the first direction D1. Consequently, the medical device 1A can curve the balloon 9B placed in the lumen 20L of the main body 20 with a large curvature.

Furthermore, the curvature of the main body 20, which bends in response to the movement of the string 4A, changes according to the amount of movement of the string 4A. Therefore, the user can adjust the amount of movement of the string 4A according to the condition of the bend in the blood vessel 8, thereby bending the main body 20 to an appropriate curvature. Consequently, the user can use the medical device 1A to deform the balloon 9B, which is used to expand the portion of the blood vessel 8 that is blocked by the stenotic lesion 80, into a desired shape.

The guide members 31A to 38A are arranged at equal intervals in the first direction D1. This allows the medical instrument 1A to uniformly deform and curve its main body 20 with approximately the same curvature from the tip 20D to the base 20P.

The tip 40D of the cord 4A is connected to the main body 20 of the main body assembly 2A. As the cord 4A moves toward the base end, the cord 4A directly applies force to the main body 20 via the tip 40D. In this way, the medical device 1A can deform the main body 20 by directly applying a pulling force to the main body 20 that pulls the cord 4A toward the base end.

The main body 20 of the main assembly 2A has an inflatable and deflated bag-like structure. When the balloon 9B, positioned within the lumen 20L of the main body 20, is deflated, the main body 20 contracts due to its own elastic force. Therefore, the possibility of the medical device 1A, moving through the blood vessel 8, catching on the inner wall and hindering its movement is reduced. Furthermore, when the balloon 9B is inflated, the main body 20 also inflates. Thus, the medical device 1A can perform treatment by deforming the balloon 9B with the main body 20, while simultaneously pushing the stenotic lesion 80 outward and expanding it with the inflated balloon 9B.

<Special notes regarding the first embodiment>
The present invention is not limited to the above embodiments, and various modifications are possible. In the above embodiments, the medical device 1A was used to deform the balloon 9B of the balloon catheter 9. In contrast, the medical device 1A may be used to deform catheters other than balloon catheters (for example, guiding catheters, support catheters, etc.) or intravascular stents. When the medical device 1A is used to deform an intravascular stent, the main body portion 20 of the main body assembly 2A may be placed inside the intravascular stent.

The main body portion 20 may be pre-curved. The shape of the main body portion 20 is not limited to a bag shape. For example, the main body portion 20 may not have a tip-side cone portion 21 and a base-side cone portion 23, and may consist only of the expansion portion 22. The main body portion 20 may be cylindrical with open base and tip ends. The main body portion 20 may have a shape similar to that of the balloon 9B when inflated and does not need to deflate. In this case, the main body portion 20 may be folded when the balloon 9B is deflated.

Of the guide members 31A to 38A, only the guide members 32A to 37A provided on the expansion portion 22 of the main body 20 may be arranged at equal intervals. The spacing between guide members 31A and 32A, and the spacing between guide members 31A and 32A, may be smaller than the spacing between guide members 32A to 37A. The number of guide members 3A is not limited to eight; it may be 1 to 7, or 9 or more.

Furthermore, by adjusting the width and number of guide members 3A in the first direction D1, the maximum curvature angle of the main body 20 when the string 4A is pulled to its maximum can be controlled. For example, the more guide members 3A there are and the larger the width in the first direction D1, the smaller the curvature of the main body 20 becomes. Conversely, the fewer guide members 3A there are and the smaller the width in the first direction D1, the larger the curvature of the main body 20 becomes. In addition, to curve the main body 20 with a large curvature, it is preferable to bring the guide member 3A located closest to the tip (for example, guide member 31A) close to the tip 20D of the main body 20, and the guide member 3A located closest to the base (for example, guide member 38A) close to the base end 20P of the main body 20.

The guide member 3A may be embedded in the main body 20. In this case, the material of the guide member 3A will be the same as that of the main body 20. In this case, the holding force of the cord 4A when the main body 20 is bent can be improved. Also, when the balloon 9B is inflated, the guide member 3A can prevent damage to the inner wall of the blood vessel 8.

The number of strings 4A is not limited to one; two or more may be used. Preferably, the strings 4A have a smooth surface and a circular cross-section to reduce the possibility of damaging the blood vessels 8. However, the cross-sectional shape of the strings 4A may also be polygonal, plate-shaped, hollow fiber, or other shapes.

Furthermore, making the cross-sectional shape of the cord 4A triangular is preferable because it enhances the expansion function of the blood vessel 8. The reason is as follows: Due to the characteristics of fluid flow within the vessel, stenotic lesions 80 tend to develop inside the bends of the blood vessel 8. In contrast, when the medical device 1A is used to expand the blood vessel 8, the cord 4A is positioned inside the bend of the blood vessel 8. By making the cord 4A triangular, the pointed portion of the cord 4A can be inserted into the inside of the bend of the blood vessel 8. Therefore, the blood vessel 8 can be expanded efficiently. It is preferable that the material of the cord 4A be metal, hardened resin, animal-derived material, plant-derived material, etc., so that the blood vessel 8 can be expanded by the cord 4A.

Furthermore, it is preferable to provide multiple cords 4A at different circumferential positions on the main body 20, as this allows for the expansion of the blood vessel 8 over a wider area in the circumferential direction of the main body 20.

The cord 4A is preferably flexible so that it can conform to the main body 20 and the blood vessel 8. Furthermore, the cord 4A is preferably rigid enough to withstand the reaction force and tension acting when the main body 20 is bent.

For example, as shown in Modification 1 in Figure 6A, the main body 20 may have a protective film 26 on the portion facing the cord 4A. The protective film 26 may be made of resin, gel, metal, or the like. The protective film 26 is positioned between the main body 20 and the cord 4A to prevent the cord 4A from directly contacting the main body 20. This protects the main body 20 of the medical device 1A by preventing friction caused by the movement of the cord 4A.

The protective film 26 may be provided on the string 4A, or on both the main body 20 and the string 4A. Alternatively, a protective body with the same function but a different shape may be provided instead of the protective film 26. The shape of the protective body may be rod-shaped, paving stone-shaped, etc.

For example, as shown in Modification 2 in Figure 6B, a restricting member 51 may be provided on the shaft 5A. The restricting member 51 is a roller that contacts the string 4A and has a ratchet function. The restricting member 51 rotates in the forward direction Y11 when the string 4A moves toward the base end, and rotates in the reverse direction Y12 when the string 4A moves toward the tip end. Furthermore, the restricting member 51 can be switched between a state where rotation in the reverse direction Y12 is permitted and a state where it is prohibited.

For example, the user sets the restricting member 51 to a state where rotation in the reverse direction Y12 is prohibited, and pulls the string 4A toward the proximal end. In this case, the string 4A can move toward the proximal end as the restricting member 51 rotates in the forward direction Y11, while movement toward the tip is restricted. Therefore, even if the user releases the force applied to the string 4A, the string 4A remains in the position moved toward the proximal end. Consequently, the main body 20 and balloon 9B remain in their deformed state. After expanding the blood vessel 8 with the medical device 1A and balloon 9B, the user switches the restricting member 51 to a state where rotation in the reverse direction Y12 is permitted. This allows the string 4A to move toward the tip. The string 4A moves toward the tip, and the main body 20 and balloon 9B return to their original state. Thus, the medical device 1A can maintain the state in which the cord 4A is moved toward the proximal end by the regulating member 51, thereby maintaining the deformed state of the main body 20 and balloon 9B caused by the movement of the cord 4A.

Furthermore, it is preferable that the restricting member 51 be provided on a portion of the shaft 5A that is always exposed to the outside. The restricting member 51 is not limited to a roller with a ratchet function. For example, the restricting member 51 may be a hook or the like that restricts the movement of the string 4A toward the end.

For example, as shown in Modification 3 in Figure 6C, the shaft 5A may be provided with through holes 52 and 53 that communicate with the lumen 50L. The through hole 52 may be provided near the tip 50D of the shaft 5A, and the through hole 53 may be provided near the base end 50P of the shaft 5A. The string 4A, which passes through the guide member 38A and extends towards the base end, may be inserted into the through hole 52, extend towards the base end within the lumen 50L, and be discharged to the outside through the through hole 53. The user may grasp the portion of the string 4A discharged from the through hole 53 and pull it towards the base end.

With the above configuration, the medical device 1A can prevent the cord 4A from getting caught on the inner wall of the blood vessel 8, hindering its movement, and also prevent the cord 4A from damaging the blood vessel 8. Furthermore, since the cord 4A is in contact with the lumen 50L of the shaft 5A, the force applied to the base end 40P of the cord 4A can be appropriately transmitted to the main body 20 and the guide member 3A.

Alternatively, instead of the insertion holes 52 and 53, a cover to enclose the string 4A may be provided on the outer surface of the shaft 5A. A cylindrical member having a lumen through which the string 4A passes may also be provided on the outer surface of the shaft 5A.

For example, as shown in Modification 4 in Figure 7, the main body 20 may have an elastic body 27. The elastic body 27 may be provided on the outer surface of the main body 20 at a position opposite the guide member 3A, straddling the central axis C11, and extending along the first direction D1. The elastic body 27 may be an elastically deformable member. A rigid body such as metal or hard resin may be used as the material for the elastic body 27.

As shown in Figure 7A, when no force acts on the string 4A and the main body 20 does not bend, the elastic body 27 extends in a straight line. In this state, no elastic force acts on the elastic body 27. On the other hand, as shown in Figure 7B, when the string 4A is pulled toward the base end and the main body 20 bends, the elastic body 27 also bends. In this case, an elastic force acts on the elastic body 27, causing it to return to its original straight shape.

Therefore, for example, if the force applied to the string 4A is released from the state shown in Figure 7B, the main body 20 will return to the state shown in Figure 7A due to the elastic force received from the elastic body 27. In this way, the medical device 1A can easily return to its original state after deformation due to the elastic force of the elastic body 27.

Furthermore, the location where the elastic body 27 is provided is not limited to the position on the outer surface of the main body 20 opposite to the guide member 3A, but may be any position on the outer surface of the main body 20. The elastic body 27 may also be embedded inside the main body 20. The elastic body 27 may be made of the same material as the main body 20.

The elastic body 27 may be made of a material capable of deforming in response to any external stimulus (e.g., ultrasound, electric current, voltage, magnetic field, etc.) (e.g., quartz crystal, magnetic nanoparticles, etc.), or it may be made of a material capable of deforming on its own (e.g., porous gel, water-absorbing gel, temperature-responsive polymer, pH-responsive polymer, etc.).

For example, as shown in Modification 5 in Figure 8A, a rigid string 4A may be used, and the main body 20 may be deformed by moving the string 4A toward the tip. In this case, the force corresponding to the movement of the string 4A toward the tip is transmitted to the tip 20D of the main body 20 via the tip 40D of the string 4A. As a result, the main body 20 deforms and curves. The direction of this curve is opposite to the direction of curve when the string 4A is pulled toward the base end.

Furthermore, as shown in the modified example 6 in Figure 8B, an elastic body 28 extending along the first direction D1 may be provided on the outer surface of the main body 20 near the guide member 3A. The elastic body 28 may apply an elastic force to the main body 20 in a direction that promotes the deformation of the main body 20 in response to the movement of the string 4A. A rigid material such as metal or hard resin may be used for the elastic body 28.

The elastic body 28 may be embedded inside the main body 20. The elastic body 28 may be made of the same material as the main body 20. Furthermore, the elastic body 27 may be made of a material capable of deforming in response to any external stimulus (e.g., ultrasound, electric current, voltage, magnetic field, etc.) (e.g., quartz crystal, magnetic nanoparticles, etc.), or it may be made of a material capable of deforming on its own (e.g., porous gel, water-absorbing gel, temperature-responsive polymer, pH-responsive polymer, etc.).

<Second Embodiment - Medical Device 1B>
Referring to Figure 9, a medical device 1B according to the second embodiment will be described. The medical device 1B includes a main body assembly 2B, guide members 31B, 32B, 33B, 34B, 35B, 36B, 37B, and 38B (hereinafter, when not distinguishing between them, they will be referred to as "guide member 3B"), a cord 4B, and a shaft 5B. The main body assembly 2B, the cord 4B, and the shaft 5B are the same as the main body assembly 2A, the cord 4A, and the shaft 5A in the medical device 1A.

The guide member 3B has a triangular cross-section when cut by a plane perpendicular to the first direction D1. One of the three sides of the guide member 3B (hereinafter referred to as the "bottom surface 361") is close to the central axis C11. Of the three corners of the guide member 3B, the corners 362, excluding the corners corresponding to both ends of the bottom surface 361, are located on the opposite side of the central axis C11 from the bottom surface 361. Therefore, when the guide member 3B is cut by a plane perpendicular to the first direction D1, the cross-section has a pointed shape on the side opposite the central axis C11. In this case, the medical device 1B can treat the stenotic lesion 80 of the blood vessel 8 by applying each pointed portion of the guide member 3B to it.

Furthermore, it is preferable to make the cross-sectional shape of the guide member 3B triangular, as this enhances the expansion function of the blood vessel 8. This is because, when the medical device 1A is used to expand the blood vessel 8, the guide member 3B is positioned inside the bend of the blood vessel 8 where stenotic lesions 80 are likely to occur. That is, by making the cross-sectional shape of the guide member 3B triangular, the pointed portion of the guide member 3B can be inserted into the inside of the bend of the blood vessel 8. Therefore, the blood vessel 8 can be expanded efficiently. It is also preferable that the guide member 3B has rigidity so that it can expand the blood vessel 8.

Furthermore, the cross-sectional shape of the guide member 3B is not limited to a triangle; it may also be a polygon with four or more sides. The guide member 3B may also be pre-coated with a drug that acts on the stenotic lesion 80 of the blood vessel 8 to efficiently treat it.

<Third Embodiment - Medical Device 1C>
Referring to Figure 10A, a medical device 1C according to the third embodiment will be described. The medical device 1C has a main body assembly 2C, guide members 31C, 32C, 33C, 34C, 35C, 36C, 37C, and 38C (hereinafter, when not distinguishing between them, they will be referred to as "guide member 3C"), a cord 4C, and a shaft 5C. The main body assembly 2C, guide members 31C to 38C, and shaft 5C are the same as the main body assembly 2A, guide members 31A to 38A, and shaft 5A in medical device 1A.

The cord 4C differs from the cord 4A of the medical device 1A in that its tip portion 40D is not connected to the main body portion 20. In the cord 4C, an annular connecting member 41 is provided at the tip portion 40D. The portion of the cord 4C closer to the base end than the guide member 38C (hereinafter referred to as the connecting portion 42) is inserted through the through-hole 40H of the connecting member 41. The tip portion 40D of the cord 4C is movably connected to the connecting portion 42 of the cord 4C. An annular portion is formed on the portion of the cord 4C closer to the tip than the connecting portion 42.

As shown in Figure 10B, with the balloon catheter 9 positioned inside the medical device 1C, the user pulls the proximal end 40P of the cord 4C toward the proximal end, simultaneously inflating the balloon 9B from its deflated state to its inflated state. As the cord 4C is pulled toward the proximal end, the proximal end 40P moves toward the proximal end. Meanwhile, the portion of the cord 4C closer to the tip 40D than the guide member 31C is folded back by the guide member 31C, and therefore moves toward the tip. In this case, the annular portion formed on the cord 4C shrinks.

The string 4C brings the guide member 3C and another guide member 3C adjacent to it in the first direction D1 close together. The portion of the main body 20 where the guide members 3C are provided flexes. As a result, the main body 20 curves. In accordance with the curvature of the main body 20, the balloon 9B inside the main body 20 also deforms and curves to follow the movement of the main body 20.

As described above, in the cord 4C, the connecting member 41 provided at the tip 40D is movably connected to the connecting portion 42 of the cord 4C. When the base end 40P of the cord 4C is pulled toward the base end, the annular portion formed on the cord 4C shrinks. In this case, the amount of movement of the cord 4C required to deform the main body 20 by bringing the distance between the guide members 3Cs of the medical device 1C is reduced compared to when the tip 40D of the cord 4C is connected to the main body 20. Therefore, the user can efficiently deform the main body 20 with a small amount of movement of the cord 4C. Furthermore, since the cord 4C shrinks the formed annular portion and brings the distance between the guide members 3Cs closer, the force acting on the base end 40P is efficiently transmitted to the guide members 3C, allowing the main body 20 to be deformed.

The connecting member 41 of the cord 4C is preferably made of a highly rigid material and has a shape that allows it to maintain a connected state with the connecting portion 42 when the main body 20 is bent. While the connecting member 41 is preferably formed as part of the cord 4C, it may also be made of a different material from the main body 20 and the cord 4C, such as metal or hard resin.

The tip 40D of the string 4C may be connected to the connecting portion 42 in a way that prevents it from moving. In this case, as the base end 40P of the string 4C is pulled toward the base end, the tip 40D of the string 4C will also move toward the base end. Furthermore, the size of the annular portion formed on the string 4C does not change even when the string 4C is pulled toward the base end.

<Fourth Embodiment - Medical Device 1D>
Referring to Figure 11, a medical device 1D according to the fourth embodiment will be described. The medical device 1D comprises a main body assembly 2D, guide members 31D, 32D, 33D, 34D, 35D, 36D, 37D, 38D, and 39D (hereinafter, when not distinguishing between them, they will be referred to as "guide member 3D"), a cord 4D, and a shaft 5D. The main body assembly 2D, the cord 4D, and the shaft 5D are the same as the main body assembly 2A, the cord 4A, and the shaft 5A in medical device 1A.

Guide members 34D, 35D, and 36D are provided on the expansion portion 22 of the main body portion 20 of the main body assembly 2D. Guide members 34D to 36D are arranged in this order at equal intervals in the first direction D1, from the tip end to the base end. The intervals in the first direction D1 between guide members 34D and 35D, and between guide members 35D and 36D, are S21. The interval S21 is greater than a predetermined first threshold Th1 (S21 > Th1).

Guide members 31D, 32D, and 33D are provided on the tip-side cone portion 21 of the main body portion 20 of the main body assembly 2D. Guide members 31D to 33D are arranged in this order at equal intervals in the first direction D1 from the tip side to the base end side. Guide members 37D, 38D, and 39D are provided on the base-side cone portion 23 of the main body portion 20 of the main body assembly 2D. Guide members 37D to 39D are arranged in this order at equal intervals in the first direction D1 from the tip side to the base end side. The intervals in the first direction D1 between guide members 31D and 32D, between guide members 32D and 33D, between guide members 37D and 38D, and between guide members 38D and 39D are S22. The interval S22 is smaller than a predetermined second threshold Th2 (Th2 > S22). Furthermore, the second threshold Th2 is smaller than the first threshold Th1 (S21 > Th1 > Th2 > S22).

As described above, unlike medical device 1A, medical device 1D has sections where the spacing between guide members 3D is S21 (guide members 34D to 36D) and sections where it is S22 (guide members 31D to 33D, 37D to 39D). In the first direction D1, the spacing S21 between guide members 34D to 36D located in the central part of the main body 20 is greater than the spacing S22 between guide members 31D to 33D located on the tip side of guide members 34D to 36D, and between guide members 37D to 39D located on the base side. In this case, when the cord 4D is pulled towards the base side, the section of the main body 20 where guide members 33D to 36D are located deforms more than the section where guide members 31D to 33D and guide members 37D to 39D are located.

Therefore, the medical device 1D can be curved such that the central portion of the main body 20 in the first direction D1 has a greater curvature than the ends in the first direction D1. In this way, the medical device 1D can be deformed into a desired shape by appropriately adjusting the spacing between the guide members 3D in the main body 20.

Furthermore, when treating a stenotic lesion 80 formed in a bend of the blood vessel 8 with a balloon catheter 9, the blood vessel 8 can be effectively expanded by deforming the balloon 9B so that the curvature of the central portion in the stretching direction is particularly large. In contrast, in the medical device 1D, the central portion of the main body 20 where the guide members 33D to 36D are provided curves with a greater curvature than the end portions where the guide members 31D to 33D and the guide members 37D to 39D are provided. Therefore, the medical device 1D can effectively expand the blood vessel 8 using the balloon catheter 9. In addition, the possibility of damaging the inner wall of the blood vessel 8 due to the expansion of the balloon 9B can be reduced.

The arrangement of the sections where the spacing between guide members 3D is greater than the first threshold Th1 and the sections where the spacing between guide members 3D is smaller than the second threshold Th2 is not limited to the above embodiment. The arrangement of the guide members 3D and the spacing between them may be appropriately changed depending on the shape of the blood vessel 8. The first threshold Th1 and the second threshold Th2 may be the same value.

In the fourth embodiment, guide members 34D to 36D are examples of the "multiple first guide members" of the present invention. Guide members 31D to 33D and 37D to 39D are examples of the "multiple second guide members" of the present invention.

<Fifth Embodiment - Medical Device 1E>
Referring to Figure 12, a medical device 1E according to the fifth embodiment will be described. The medical device 1E includes a main body assembly 2E, guide members 31E to 36E (hereinafter, when not distinguishing between them, they will be referred to as "guide member 3E"), guide members 31F to 36F (hereinafter, when not distinguishing between them, they will be referred to as "guide member 3F"), a cord 4E, and a shaft 5E. The main body assembly 2E is the same as the main body assembly 2A in medical device 1A. The shaft 5E is the same as the shaft 5A of medical device 1A in the third modified example.

Guide member 31E is provided on the outer surface of the main body 20. Guide member 31E is provided on the tip-side cone portion 21 of the main body 20. Guide member 36E is provided on the base-side cone portion 23 of the main body 20. Guide members 32E to 35E are provided on the expansion portion 22 of the main body 20. Guide members 31E to 36E are arranged at equal intervals in the first direction D1.

Guide member 31F is positioned on the outer surface of the main body 20 at a different location from guide member 3E in the circumferential direction around the central axis C11. Guide member 31F is provided on the tip-side cone portion 21 of the main body 20. Guide member 36F is provided on the base-side cone portion 23 of the main body 20. Guide members 32F to 35F are provided on the expansion portion 22 of the main body 20. Guide members 31F to 36F are arranged at equal intervals in the first direction D1.

Guide members 31E, 31F, 32E, 32F, 33E, 33F, 34E, 34F, 35E, 35F, and 36E, 36F are each positioned at the same location in the first direction D1 and are aligned circumferentially around the central axis C11.

The string 4E is inserted through the through holes 30H of the guide members 36E, 35F, 34E, 33F, 32E, 31F, 31E, 32F, 33E, 34F, 35E, and 36F in that order, reaching the tip 40D. In other words, the string 4E is alternately inserted through the through holes 30H of the guide member 3E and the through holes 30H of the guide member 3F.

An annular connecting member 41 is connected to the tip 40D of the string 4E. The connecting portion 43 of the string 4E, closer to the base end than the guide member 36E, is inserted through the through-hole 40H of the connecting member 41. The tip 40D of the string 4E is movably connected to the connecting portion 43 of the string 4E.

With the balloon catheter 9 positioned inside the medical device 1E, the user pulls the proximal end 40P of the string 4E toward the proximal end, simultaneously inflating the balloon 9B from its deflated state to its inflated state. The string 4E brings together guide member 3E and other guide members 3E adjacent to it in the first direction D1. Similarly, the string 4F brings together guide member 3F and other guide members 3F adjacent to it in the first direction D1. Furthermore, the string 4E brings together guide members 31E, 31F, 32E, 32F, 33E, 33F, 34E, 34F, 35E, 35F, and 36E, 36F in the circumferential direction.

As a result, the area of the main body 20 that includes the parts where the guide members 3E and 3F are provided will flex. This causes the main body 20 to curve. In accordance with the curvature of the main body 20, the balloon 9B inside the main body 20 also deforms and curves to follow the movement of the main body 20.

Therefore, the medical device 1E can deform its main body 20 over a wide area in both the first direction D1 and the circumferential direction. As a result, even when the portion of the blood vessel 8 where the stenotic lesion 80 is formed has a complex shape, the medical device 1E can appropriately expand it using the balloon catheter 9.

Furthermore, the cord 4E is alternately inserted through the through-holes 30H of the guide member 3E and the through-holes 30H of the guide member 3F. In this case, the medical device 1E can apply a force corresponding to the movement of the cord 4E evenly to the guide members 3E and 3F. Therefore, the medical device 1E can smoothly deform the main body 20.

In the above, the spacing between guide members 3E and between guide members 3F does not have to be equal. Guide members 3E and 3F may be positioned at different locations in the first direction D1. Guide members 3E and 3F may be arranged alternately in the first direction D1. The string 4E may be inserted through the respective through holes 30H of guide members 36E, 35E, 34E, 33E, 32E, 31E, 31F, 32F, 33F, 34F, 35F, and 36F in that order.

Medical device 1E had two rows of guide members 3E and 3F aligned in the first direction D1, but three or more rows of guide members may be provided. The tip 40D of the cord 4E may be connected to the connecting portion 43 in a manner that prevents movement.

In the fifth embodiment, guide member 3E is an example of the "multiple third guide members" of the present invention. Guide member 3F is an example of the "multiple fourth guide members" of the present invention.

<Sixth Embodiment - Balloon Catheter 90>
The balloon catheter 90 shown in Figure 13 further comprises guide members 31G, 32G, 33G, 34G, 35G, 36G, 37G, 38G (hereinafter referred to as "guide member 3G" when not distinguished from each other) and a string 4F relative to the balloon catheter 9 (see Figure 2). The guide members 3G and string 4F are the same as the guide member 3A and string 4A in medical device 1A. The direction extending along the outer surface of the balloon 9B from the tip to the base of the balloon 9B is referred to as the "second direction D2".

Guide member 31G is provided on the tip cone portion 93 of balloon 9B. Guide member 38G is provided on the base cone portion 95 of balloon 9B. Guide members 32G to 37G are provided on the inflatable portion 94 of balloon 9B. Guide members 31G to 38G are arranged in this order from the tip to the base in the second direction D2. The shape and arrangement of guide members 31G to 38G correspond to guide members 31A to 38A of medical device 1A.

In the balloon catheter 90, the distance between the guide members 3G on the balloon 9B decreases in response to the operation of pulling the string 4F towards the proximal end. This causes the balloon 9B to deform. Because the balloon catheter 90 allows the balloon 9B to be bent with a large curvature by manipulating the string 4F, the shape of the balloon 9B can be deformed into a desired shape. Furthermore, deformation of the balloon 9B is possible not only in the inflated state but also in the deflated state.

Furthermore, the guide member and cord are not limited to being attached to a balloon catheter; they may also be attached to other well-known medical devices used in intravascular interventions, such as scoring balloon catheters and stents.

1, 1A, 1B, 1C, 1D, 1E: Medical device 2A, 2B, 2C, 2D, 2E: Main assembly 3A, 3B, 3C, 3D, 3E, 3F, 3G: Guide member 4A, 4B, 4C, 4D, 4E, 4F: Cord 5A, 5B, 5C, 5D, 5E: Shaft 9, 90: Balloon catheter 9A: Catheter shaft 9B: Balloon 26: Protective membrane 27, 28: Elastic body 51: Regulating member 52, 53: Insertion hole

Claims (16)

A main body assembly including at least a main body portion having a lumen,
Multiple guide members are provided on the outer surface of the main body, each having a through hole, and are arranged at intervals in a first direction along the outer surface of the main body.
A medical device comprising a string that is inserted through the through holes of each of the plurality of guide members and is movable to one side or the other in the first direction, wherein the movement of the string changes the spacing between each of the plurality of guide members in the first direction, causing the main body to deform. The aforementioned plurality of guide members are
A plurality of first guide members, the spacing between them in the first direction being greater than a first value ,
It has a plurality of second guide members whose spacing in the first direction is smaller than a second value ,
The medical device according to claim 1, characterized in that the first value is greater than the second value . The plurality of first guide members are provided in the central part of the main body in the first direction,
The medical device according to claim 2, characterized in that the plurality of second guide members are provided on one side of the main body with respect to the plurality of first guide members in the first direction and on the other side of the main body with respect to the plurality of first guide members in the first direction. The medical device according to claim 1, characterized in that the plurality of guide members are arranged at equal intervals in the first direction. The aforementioned plurality of guide members are
A plurality of third guide members arranged in the first direction,
The medical device according to any one of claims 1 to 4, characterized in that it has a plurality of fourth guide members arranged at different positions in the circumferential direction around an axis extending along the center of the main body and aligned in the first direction with respect to the plurality of third guide members. The aforementioned string is
The medical device according to claim 5, characterized in that the multiple third guide members are alternately inserted into the through holes of each of the multiple fourth guide members. The medical device according to any one of claims 1 to 6, characterized in that when the plurality of guide members are cut in a plane perpendicular to the first direction, the cross-section has a shape in which the end opposite to the axis extending along the center of the main body is pointed. The aforementioned string is
One end is connected to the main assembly,
A medical device according to any one of claims 1 to 7, characterized in that it moves in the first direction in response to a force acting on the other end. The aforementioned string is
One end is connected to the portion of the string other than the one end,
A medical device according to any one of claims 1 to 7, characterized in that it moves in the first direction in response to a force acting on the other end. The medical device according to claim 9, characterized in that one end of the cord is movably connected to the portion of the cord excluding the one end. The medical device according to any one of claims 1 to 10, further comprising a protective film disposed between the main body and the string. The medical device according to any one of claims 1 to 11, characterized in that the main body portion is provided with an elastic body at a position different from the plurality of guide members in the circumferential direction with respect to an axis extending along the center of the main body portion. The main body is further equipped with a shaft connected to the main body,
The aforementioned shaft is
A medical device according to any one of claims 1 to 12, characterized in that it has an insertion hole through which the string is inserted. The medical device according to any one of claims 1 to 13, further comprising a restricting member for restricting the movement of the string along the first direction. The medical device according to any one of claims 1 to 14, characterized in that the main body has an expandable and contractible bag shape. Balloons and
The shaft to which the balloon is connected,
Multiple guide members are provided on the outer surface of the balloon, each having a through hole, and are arranged at intervals along the long axis direction parallel to the outer surface of the balloon.
A balloon catheter comprising a string that is inserted through the through-holes of each of the plurality of guide members and is movable to one or the other side in the longitudinal direction, wherein the balloon deforms as the string moves in the longitudinal direction, causing the distance between each of the plurality of guide members in the longitudinal direction to change.