Balloon catheter system

Abstract

This invention relates to a balloon catheter system, comprising a first catheter and a second catheter. A working balloon is disposed at the distal end of the second catheter. At least a portion of the second catheter is located within the first catheter. The first catheter includes a proximal segment, a middle segment, and a distal segment distributed sequentially from proximal to distal. The middle segment includes an outer portion and a medial portion, and has a natural state and a deformed state. When the middle segment transitions from the natural state to the deformed state, the outer and medial portions move away from each other, and the distal segment moves towards the proximal end. By providing a deformable middle segment, the distance to the distal end can be adjusted by changing the shape of the middle segment, thereby allowing the force or the object of action to be directly located at the distal end of the catheter, reducing the problems of delay and loss in the transmission of force and action due to excessive travel in the prior art.

Description

Technical Field

[0001] This invention relates to the field of interventional medical device technology, and in particular to a balloon catheter system. Background Technology

[0002] Interventional therapy is a minimally invasive treatment technique that uses catheters and other instruments under the guidance of medical imaging equipment to treat diseases. The delivery of the catheter is a crucial step in interventional therapy. For balloon catheters, the procedure typically involves pushing the balloon out of the sheath or retracting the sheath to expose the balloon. However, this conventional method of sheath withdrawal or balloon deployment requires external pushing and pulling movements. Because the catheter is relatively long and flexible within the body, external distance control cannot directly correspond to internal displacement changes. Furthermore, there is a delay in the transmission of external displacement to the internal system. For example, the operator may push the catheter a suitable distance, but the balloon may only move a small distance or remain stationary for a long time, leading the operator to misjudge that further pushing is necessary. In other words, current techniques are prone to causing the advance or retraction distance to be too long or too short. Summary of the Invention

[0003] Therefore, it is necessary to provide an improved balloon catheter system to address the delivery problems existing in current balloon catheter systems, as follows: A balloon catheter system is provided, including a first catheter and a second catheter, wherein a working balloon is disposed at the distal end of the second catheter, at least a portion of the second catheter is located within the first catheter, and the first catheter includes a proximal segment, a middle segment and a distal segment distributed sequentially from proximal to distal, the middle segment including an outer portion and an inner portion, the middle segment including a natural state and a deformed state, wherein during the transition of the middle segment from the natural state to the deformed state, the outer portion and the inner portion move away from each other, and the distal segment moves towards the proximal end.

[0004] In one embodiment, the intermediate segment includes a first balloon located between the outer and inner portions, the inflation channel of the first balloon communicating with the outside via the proximal segment, and the intermediate segment entering a deformable state after the first balloon is inflated.

[0005] In one embodiment, the intermediate segment includes a mesh-like woven structure.

[0006] In one embodiment, the first balloon and / or the working balloon are non-compliant balloons.

[0007] In one embodiment, after the first balloon is inflated, there is a gap between the outermost part of the first balloon and the outermost part of the outer portion of the middle segment.

[0008] In one embodiment, the outer surface of the working balloon is coated with a drug layer.

[0009] In one embodiment, a separator is further included that is detachably fitted onto the surface of the working balloon, the separator preventing contact between the working balloon and the inner wall of the first catheter.

[0010] In one embodiment, after the outer and inner portions of the intermediate segment move away from each other, the second catheter moves within the first catheter, causing the isolator to abut against the inner portion from proximal to distal, and the isolator moves proximally relative to the working balloon to detach from the surface of the working balloon.

[0011] In one embodiment, the working balloon can pass axially through the intermediate section region.

[0012] In one embodiment, the outer diameter of the nearest end of the spacer is larger than the outer diameter of the farthest end.

[0013] Compared with existing technologies, the present invention provides a balloon catheter system including a first catheter and a second catheter. A working balloon is disposed at the distal end of the second catheter. At least a portion of the second catheter is located within the first catheter. The first catheter includes a proximal segment, a middle segment, and a distal segment distributed sequentially from proximal to distal. The middle segment includes an outer portion and a medial portion, and the middle segment has a natural state and a deformed state. When the middle segment transforms from the natural state to the deformed state, the outer portion and the medial portion move away from each other, and the distal segment moves towards the proximal end. By providing a deformable middle segment, the distance to the distal end can be adjusted by changing the shape of the middle segment, thereby allowing the force or the object of action to be directly located at the distal end of the catheter, reducing the problems of delay and loss in the transmission of force and action due to excessive travel in existing technologies. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of the first catheter of the balloon catheter in its natural state in Embodiment 1 of the present invention; Figure 2 This is a schematic diagram of the delivery state of the balloon catheter in Embodiment 1 of the present invention; Figure 3 This is a schematic diagram of the release state of the balloon catheter in Embodiment 1 of the present invention; Figure 4 This is a schematic diagram of the second stage starting state of the balloon catheter in Embodiment 2 of the present invention; Figure 5 yes Figure 4 Enlarged view of region A in the middle; Figure 6 This is a schematic diagram of the second-stage end state of the balloon catheter in Embodiment 2 of the present invention; Figure 7 yes Figure 6 Enlarged view of region B in the middle; Figure 8 This is a schematic diagram of the third stage starting state of the balloon catheter in Embodiment 2 of the present invention; Figure 9 This is a schematic diagram of the third stage of the balloon catheter in Embodiment 2 of the present invention. Figure 10 This is a schematic diagram of the first catheter of the balloon catheter in its natural state in another embodiment of the present invention; Figure 11 This is a schematic diagram of the first catheter of the balloon catheter in a deformed state according to another embodiment of the present invention. Detailed Implementation

[0015] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0016] It should be noted that in the field of interventional medical devices, the end of a medical device implanted in the human or animal body that is closer to the operator is generally called the "proximal end," and the end that is farther from the operator is called the "distal end." Based on this principle, the "proximal end" and "distal end" of any component of a medical device are defined. "Axial direction" generally refers to the length direction of the medical device during delivery, and "radial direction" generally refers to the direction of the medical device perpendicular to its "axial direction." Based on this principle, the "axial direction" and "radial direction" of any component of a medical device are defined. The "connection" mentioned in the embodiments includes both direct connection between two components and indirect connection via other components.

[0017] The technical solution of the present invention will be further described in detail below with reference to specific embodiments.

[0018] Example 1 Reference Figure 1-3 , Figure 1 This is a schematic diagram of the structure of the first catheter of the balloon catheter in its natural state in Embodiment 1 of the present invention; Figure 2 This is a schematic diagram of the delivery state of the balloon catheter in Embodiment 1 of the present invention; Figure 3 This is a schematic diagram of the release state of the balloon catheter in Embodiment 1 of the present invention; in this embodiment, the balloon catheter system 100 includes a first catheter 110 and a first catheter seat 120, with the proximal end of the first catheter 110 connected to the first catheter seat 120.

[0019] In this embodiment, the first catheter 110 is distributed from the proximal end to the distal end as a proximal segment 111, an intermediate segment 112, and a distal segment 113. The proximal segment 111 is the main delivery segment of the first catheter 110, which is generally tubular. The intermediate segment 112 is the connecting part of the proximal segment 111 and the distal segment 113. In this embodiment, the intermediate segment 112 is deformable. Preferably, the intermediate segment 112 includes a braided structure. In this embodiment, the braided structure is preferably a mesh structure woven from nickel-titanium alloy. In its natural state, the intermediate segment 112 extends along the extension direction of the proximal segment 111 and the distal segment 113, that is, the three are generally cylindrical.

[0020] In this embodiment, the intermediate section 112 includes an outer portion 1122 and an inner portion 1121. In addition, a first balloon 130 is provided in the intermediate section 112. The first balloon 130 is located between the outer portion 1122 and the inner portion 1121. The inflation channel of the first balloon 130 is connected to the outside through the proximal section 111. After the first balloon 130 is inflated, the outer portion 1122 and the inner portion 1121 of the intermediate section 112 move away from each other.

[0021] In this embodiment, the intermediate segment 112 is deformable. When the first balloon 130 inflates, it abuts against or causes the outer portion 1122 to deform outward (i.e., the side away from the axis) from the inside, forming a combination of a balloon and a braided mesh that abuts against the inner wall of the blood vessel, thereby providing support for the distal end of the first catheter 110 and maintaining the distal end of the first catheter 110 in the middle position of the blood vessel. Simultaneously, when the first balloon 130 inflates, it abuts against... The first balloon 130 inflates, causing the inner portion 1121 to deform and protrude inward (i.e., towards the axis). Simultaneously, when the first balloon 130 inflates, it supports or causes the outer portion 1122 to deform and protrude outward from the inside, and supports or causes the inner portion 1121 to deform and protrude inward from the inside. The proximal end of the intermediate segment 112 is fixedly connected to the proximal segment 111, and the distal end of the intermediate segment 112 moves towards the proximal end, thereby causing the distal segment 113 to move closer to the proximal segment 111. In summary, the inflation of the first balloon 130 causes at least the aforementioned three changes.

[0022] In another embodiment, the intermediate segment 112 includes an outer portion 1122 and an inner portion 1121, from which pull wires extend to the proximal end of the first catheter 110. Tightening the pull wires can also cause the outer portion 1122 and the inner portion 1121 of the intermediate segment 112 to move away from each other. For this embodiment, it is sufficient to control the outer portion 1122 and the inner portion 1121 of the intermediate segment 112 to move away from each other. By causing the outer portion 1122 and the inner portion 1121 of the intermediate segment 112 to move away from each other, the distal segment 113 can move towards the proximal end. In this embodiment, the first balloon 130 is preferred, as the process of the outer portion 1122 and the inner portion 1121 of the intermediate segment 112 moving away from each other is more stable and results in more uniform stress.

[0023] In this embodiment, the middle segment 112 is in a natural state when it is not subjected to external force. When the outer side 1122 and the inner side 1121 of the middle segment 112 are far apart, it is in a deformed state. When the middle segment 112 changes from a natural state to a deformed state, the outer side 1122 and the inner side 1121 are far apart, and the distal segment 113 moves toward the proximal end.

[0024] In this embodiment, the second catheter 210 is used to deliver the working balloon 220. The second catheter 210 is movably inserted into the first catheter seat 10, and at least a portion of the second catheter 210 is located within the first catheter 110. The working balloon 220 is connected to the distal end of the second catheter 210, and the inflation channel of the working balloon 220 communicates with the outside via the second catheter 210. The working balloon 220 has an initial state and a released state. In the initial state, the working balloon 220 is folded and housed within the first catheter 110. When switching from the initial state to the released state, the working balloon 220 detaches from the first catheter 110 and reaches a predetermined position. After being inflated, the working balloon 220 abuts against the inner wall of the blood vessel at the lesion site.

[0025] By utilizing the coordination of the intermediate segment 112 and the first balloon 130, the first catheter 110 can be moved proximally. For the release of the working balloon 220, it can be first delivered to the distal end of the first catheter 110, and then the distal segment 113 of the first catheter 110 can be withdrawn by inflating the first balloon 130, thereby releasing the working balloon 220. This method retains the centering effect provided by the first balloon 130 while avoiding excessive withdrawal of the first catheter 110 or excessive extension of the second catheter 210, because the volume change of the inflated first balloon 130 directly corresponds to the deformation of the intermediate segment 112, which is reflected in the retraction of the distal segment 113. In the prior art, the conventional release method of withdrawing the first catheter 110 or pushing out the second catheter 210 requires external pushing and pulling actions, which can easily cause the pushing or pulling distance to be too long. Even if the external stroke can be precisely controlled, because the catheter is long in the body and has a certain degree of flexibility, the external distance control cannot directly correspond to the displacement change in the body. Therefore, the release method using the deformation of the middle section 112 has better stability.

[0026] In another embodiment, the first balloon 130 is a non-compliant balloon. After the first balloon 130 is inflated, there is a gap between the outermost part of the first balloon 130 and the outermost part of the outer side 1122 of the middle section 112, so as not to obstruct blood flow.

[0027] In another embodiment, the working balloon 220 is also selected as a non-compliant balloon.

[0028] The balloon and balloon catheter in this embodiment can be used to deliver various stents, including but not limited to coronary stents, peripheral stents, femoral artery stents, iliac artery stents, infrakal stents, and intracranial stents.

[0029] Example 2 The main difference between Example 2 and Example 1 lies in the arrangement of the isolation components, as detailed in 4-9. Figure 4 This is a schematic diagram of the second stage starting state of the balloon catheter in Embodiment 2 of the present invention; Figure 5 yes Figure 4 Enlarged view of region A in the middle; Figure 6 This is a schematic diagram of the second-stage end state of the balloon catheter in Embodiment 2 of the present invention; Figure 7 yes Figure 6 Enlarged view of region B in the middle; Figure 8 This is a schematic diagram of the third stage starting state of the balloon catheter in Embodiment 2 of the present invention; Figure 9 This is a schematic diagram of the third stage of the balloon catheter in Embodiment 2 of the present invention. When the working balloon 220 is a drug-loaded balloon, its outer surface is coated with a drug layer. When the working balloon 220 inflates and contacts the inner wall of the blood vessel at a predetermined position, the drug layer contacts the lesion site of the blood vessel. However, when the working balloon 220 moves within the first catheter 110, its continuous contact with and sliding against the inner wall of the first catheter 110 can easily cause the drug layer coated on its surface to be lost or detached. This can result in the working balloon 220 failing to achieve the expected effect or having a reduced effect. Therefore, this embodiment adds an isolation element 300. The isolation element 300 is used to cover the outside of the working balloon 220 to isolate the working balloon 220 from the inner wall of the first catheter 110. Simultaneously, the isolation element 300 can also act as a guide within the first catheter 110, improving the smoothness of the working balloon 220's movement within the first catheter 110 (the working balloon 220 is prone to unfolding and swinging in its folded state, resulting in significant resistance when contacting the inner wall of the first catheter 110).

[0030] The maximum outer diameter of the isolation element 300 is smaller than the expansion radius of the first balloon 220. Therefore, after the first balloon 220 expands, the isolation element 300 cannot pass through the middle section 112 area. In particular, in this embodiment, the first balloon 220 causes the braided structure of the middle section 112 to deform. The braided structure enhances the strength of the outer surface of the original first balloon 220, thereby making the obstruction of the isolation element 300 more stable.

[0031] In this embodiment, the isolator 300 is detachably fitted onto the outside of the working balloon 220, and the isolator 300 moves proximally relative to the working balloon 220 to achieve detachment.

[0032] In this embodiment, the spacer 300 is first fitted onto the outside of the working balloon 220. Then, the second catheter 210 is used to guide the working balloon 220 and the spacer 300 into the first catheter 110 to bring the balloon catheter to its initial state. The initial state of the balloon catheter is the state in which the working balloon 220 is about to be delivered after the sheath reaches the predetermined position to be implanted. The transition from the initial state to the release state includes a first stage, a second stage, and a third stage, as detailed below: In the first stage, the second catheter 210 moves from the proximal end to the distal end within the first catheter 110, causing the working balloon 220 and the isolation element 300 sleeved on the outside of the working balloon 220 to gradually approach the distal end, that is, to gradually approach the region of the middle section 112 in the axial direction.

[0033] In the second phase, refer to Figure 4-6The first balloon 130 inflates, thereby the first balloon 130 supports or drives the outer part 1122 to deform and bulge outward from the inside, and supports or drives the inner part 1121 to deform and bulge inward from the inside. At this time, the distal segment 113 of the first catheter 110 moves towards the proximal end due to the deformation of the middle segment 112, and is supported by the blood vessel by the middle segment 112. The distal segment 113 is basically in the position of the blood vessel axis. The second catheter 210 continues to move towards the distal end until the isolation element 300 reaches the position of the middle segment 112 from the proximal end to the distal end.

[0034] In the third stage, refer to Figure 8-9 The second catheter 210 continues to move distally, with the isolator 300 abutting against the inner portion 1121 of the intermediate section 112. The working balloon 220 gradually passes through the cavity in the central region of the intermediate section 112, while the isolator 300 is blocked by the inner portion 1121 of the intermediate section 112, remaining near or proximal to the intermediate section 112. Thus, the isolator 300 gradually moves distally relative to the working balloon 220, and simultaneously detaches from the working balloon 220. At the end of the third stage, the working balloon 220, after leaving the region of the intermediate section 112, leaves the distal end of the first catheter 110 and is released, while preserving the drug-loaded coating on the surface of the working balloon 220 to the maximum extent possible.

[0035] In another embodiment, the intermediate segment 112 is formed directly from the first balloon 130, with the inner side 1121 of the intermediate segment 112 being the inner side of the first balloon 130 and the outer side 1122 of the intermediate segment 112 being the outer side of the first balloon 130, thereby obtaining an intermediate segment 112 with higher flexibility.

[0036] In this embodiment, the outer diameter of the nearest end of the isolator 300 is larger than the outer diameter of the farthest end. Preferably, the outer diameter gradually increases from the far end to the near end. The smaller outer diameter of the far end facilitates the movement of the proximal end of the isolator 300 in the first conduit 110 and its passage through the region of the intermediate section 112. That is, after the outer side 1122 and the inner side 1121 move away from each other, the outer diameter of the nearest end of the isolator 300 is smaller than the inner cavity of the intermediate section 112 (the inner cavity channel formed by the inner side 1121 inside the first conduit 110), thereby allowing the nearest end of the isolator 300 to extend into or pass through the region of the intermediate section 112.

[0037] In another embodiment, after the first balloon 130 is inflated, the outer diameter of the distal end of the spacer 300 is smaller than the inner diameter of the cavity in the central region of the intermediate section 112, and the proximal end of the spacer 300 is located on the side of the inner side 1121 of the intermediate section 112 away from the axis, so that the proximal end of the spacer 300 can pass smoothly through the position of the smallest inner diameter of the intermediate section 112, thereby allowing the working balloon 220 to be transported smoothly toward the distal end.

[0038] In this embodiment, when the intervention is completed and withdrawal is required, on the one hand, negative pressure can be drawn from the first balloon 130, so that the intermediate section 112 returns to its natural state and the distal end of the first catheter 110 returns to its straight cylindrical shape, then the first catheter 110 can be withdrawn smoothly. Before this, the working balloon 220 has been depressurized and retracted into the interior of the first catheter 110. After the isolation element 300 loses the restriction of the intermediate section 112, it is still restricted by the working balloon 220. Therefore, the isolation element 300 will not detach from the first catheter 110 at the distal end, and the entire catheter system operates stably.

[0039] In another embodiment, an auxiliary catheter is also inserted inside the second catheter 210. The auxiliary catheter can deliver a blocking balloon to block the distal side of the working balloon 210, thereby making the release process of the working balloon 210 more stable.

[0040] In this embodiment, after the first balloon 130 is inflated, the proximal end 1121 and the distal end 1122 of the intermediate segment 112 deform simultaneously. This serves to support and center the distal end of the first catheter 110, and also to restrict and block the isolator 300. It should also be noted that by using the cooperation of the intermediate segment 112 and the first balloon 130, the first catheter 110 can be moved towards the proximal end. Therefore, if the working balloon 220 does not consider the isolator 300 to reduce drug coating wear and maintain smooth transport (i.e., the working balloon 220 is not a drug-loaded balloon), the isolator 300 can also form a damping section when it reaches the position of the intermediate segment 112, thereby indicating to the operator that it has entered the release state.

[0041] In another embodiment, the first balloon 130 is not spherical, and the inner surface of the first balloon 130 has multiple stepped surfaces (or constricted portions). The corresponding isolation member 300 has a protrusion at the matching step or constricted position, thereby achieving stable blocking of the isolation member 300.

[0042] In another embodiment, reference Figure 10-11 , Figure 10 This is a schematic diagram of the first catheter of the balloon catheter in its natural state in another embodiment of the present invention; Figure 11This is a schematic diagram of the first catheter of the balloon catheter in a deformed state according to another embodiment of the present invention. Multiple blocking elements 1123 are provided on the inner side of the intermediate section 112, located on the proximal side of the intermediate section 112. In the initial state, the blocking elements 1123 extend radially inward. The multiple blocking elements 1123 block the inner lumen of the first catheter 110, thereby preventing the second catheter 210 from directly detaching from or extending distally from the first catheter 110 in the initial state, thus improving safety. However, when the first balloon 130 is inflated, because the blocking elements 1123 are located... At the proximal end of the intermediate section 112, the blocking member 1123 rotates as the first balloon 130 is inflated. The blocking member 1123 rotates from a radially extending direction to an inclined extension towards the proximal end, thereby leaving a cavity in the central region of the intermediate section 112. Furthermore, the blocking member 1123 can also be used to block the isolator 300. The stress of the blocking member 1123 on the isolator 300 is concentrated at the free end of the blocking member 1123, and the pressure is greater than that of the surface contact between the isolator 300 and the inner side 1121 of the intermediate section 112, that is, the blocking effect is better.

[0043] In another embodiment, the proximal side of the isolator 300 is sleeved on the surface of the second conduit 210 and the two are connected by threads. After the isolator 300 abuts against the intermediate section 112, the second conduit 210 is rotated to unlock the isolator 300, thereby preventing the isolator 300 from dislodging from the working balloon 220 due to friction before the isolator 300 abuts against the intermediate section 112.

[0044] It should be noted that the technical features of the above embodiments can be combined arbitrarily and can also be applied to various types of catheters and catheters with similar structures. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described; however, as long as the combination of these technical features does not contradict each other, it should be considered within the scope of this specification.

[0045] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A balloon catheter system, characterized in that, The device includes a first catheter and a second catheter. A working balloon is disposed at the distal end of the second catheter. At least a portion of the second catheter is located within the first catheter. The first catheter includes a proximal segment, a middle segment, and a distal segment distributed sequentially from proximal to distal. The proximal side of the middle segment is fixedly connected to the proximal segment. The middle segment includes an outer portion and an inner portion. The middle segment includes a natural state and a deformed state. During the transition of the middle segment from the natural state to the deformed state, the outer portion and the inner portion move away from each other, and the distal segment moves towards the proximal end to achieve the release of the working balloon. The intermediate segment includes a first balloon located between the outer and inner portions. The inflation channel of the first balloon connects to the outside via the proximal segment. After the first balloon is inflated, the intermediate segment deforms. At this time, the first balloon supports the distal end of the first catheter, thereby maintaining the distal end of the first catheter in the middle position of the blood vessel. Simultaneously, the distal side of the intermediate segment moves towards the proximal end, thereby causing the distal segment to move closer to the proximal segment, thus releasing the working balloon.

2. The balloon catheter system according to claim 1, characterized in that, The middle section includes a mesh-like woven structure.

3. The balloon catheter system according to claim 1, characterized in that, The first balloon and / or the working balloon are non-compliant balloons.

4. The balloon catheter system according to claim 1, characterized in that, After the first balloon is inflated, there is a gap between the outermost part of the first balloon and the outermost part of the outer side of the middle section.

5. The balloon catheter system according to any one of claims 1-4, characterized in that, The outer surface of the working balloon is coated with a drug layer.

6. The balloon catheter system according to claim 5, characterized in that, It also includes a separator that is detachably fitted onto the surface of the working balloon, the separator preventing contact between the working balloon and the inner wall of the first catheter.

7. The balloon catheter system according to claim 6, characterized in that, After the outer and inner portions of the intermediate section move away from each other, the second catheter moves in the first catheter, causing the isolator to abut against the inner portion from the proximal end to the distal end. The working balloon gradually passes through the cavity in the central region of the intermediate section, while the isolator is blocked by the inner portion of the intermediate section and remains at the proximal side of the intermediate section.

8. The balloon catheter system according to claim 7, characterized in that, The outer diameter of the nearest end of the isolator is larger than the outer diameter of the farthest end.

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