A rapid exchange microcatheter and stent delivery device

Abstract

The present invention provides a rapid exchange microcatheter and a stent delivery device, belonging to the technical field of stent delivery devices; the rapid exchange microcatheter includes a microcatheter body, and a rapid exchange port is provided on the side wall at a set distance from the distal end of the microcatheter body. It is characterized in that a soft and elastic recoverable sealing film is fixedly connected to the rapid exchange port for guiding wires to pass through. After the guiding wire passes through the recoverable sealing film, it is tightened by the recoverable sealing film. When the guiding wire is withdrawn from the microcatheter body, the perforation of the recoverable sealing film restores the sealing of the rapid exchange port; to solve the technical problems in the prior art that due to the existence of the rapid exchange port, blood is likely to enter the push catheter through the rapid exchange port, the rapid exchange port destroys the integrity of the microcatheter itself, resulting in weak links in the microcatheter, reducing the surgical efficiency and increasing the risk probability of the operation, and the guiding wire cannot be effectively fixed after passing through the rapid exchange port, easily causing the guiding wire to displace and twist in the blood vessel.

Description

Technical Field

[0001] The present invention belongs to the technical field of stent delivery devices, and particularly relates to a rapid exchange microcatheter and a stent delivery device. Background Art

[0002] A stent is a support structure used in the diseased segment of a blood vessel to support the stenotic segment of the blood vessel, which can reduce the elastic recoil and remodeling of the blood vessel and keep the blood vessel unobstructed. It is mainly divided into coronary stents, cerebrovascular stents, renal artery stents, aortic stents, peripheral vascular stents, etc.

[0003] The existing self-expanding stent needs to be compressed and restricted in a delivery catheter before installation. When installing, the delivery catheter transports the stent to the lesion location and then releases the stent. After being released, the stent automatically expands at the lesion location to support the blood vessel.

[0004] Specifically, when the delivery catheter delivers the stent to the lesion location, a stent delivery device is first required. The stent delivery device includes an operating handle and a microcatheter. A rapid exchange port is opened at a position 20 cm - 35 cm from the distal end of the microcatheter. After the surgical operation of the microcatheter reaches near the lesion location in the blood vessel, a guide wire is delivered into the blood vessel. The function of the guide wire is to accurately locate the lesion location. After the guide wire reaches near the lesion location, it enters the interior of the microcatheter through the rapid exchange port on the microcatheter. Then, the microcatheter is guided to the accurate lesion location. Then, the guide wire is withdrawn, and the delivery catheter is pushed into the microcatheter. The delivery catheter carries the stent to the lesion location and then releases the stent.

[0005] However, due to the existence of the rapid exchange port, the microcatheter has the following problems:

[0006] (1) The microcatheter with a rapid exchange port cannot ensure the sealing of the microcatheter. If normal saline or contrast agent is not injected in time after the guide wire is withdrawn, it is easy for blood to enter through the rapid exchange port or for the middle reinforcing layer to be in direct contact with the blood.

[0007] (2) The design of the traditional rapid exchange port destroys the integrity of the microcatheter body itself, and damages the performance such as the support of the tube body itself, resulting in the rapid exchange port position becoming a weak link, which requires doctors to divert their attention to pay extra attention during the operation, reducing the operation efficiency and increasing the risk probability of the operation.

[0008] (3) Since the diameter of the rapid exchange port is larger than the diameter of the guide wire, the guide wire passing through the rapid exchange port cannot be properly fixed, and the guide wire may be displaced or twisted in the blood vessel during the operation.

[0009] (4) The existing rapid exchange port is too far from the distal end. When the guide wire enters the microcatheter through the rapid exchange port and advances distally, the resistance is large, which is inconvenient for surgical operation. Summary of the Invention

[0010] The object of the present invention is to provide a rapid exchange microcatheter to solve the technical problems in the prior art that due to the existence of the rapid exchange port, blood is likely to enter the microcatheter through the rapid exchange port, and the rapid exchange port destroys the integrity of the microcatheter itself, resulting in weak links in the microcatheter, reducing the surgical efficiency, increasing the risk probability of the operation, and the guide wire cannot be effectively fixed after passing through the rapid exchange port, easily causing displacement and torsion of the guide wire in the blood vessel; the present invention also provides a stent delivery device to solve the above technical problems.

[0011] In order to achieve the above object, the rapid exchange microcatheter of the present invention provides the following technical solutions:

[0012] A rapid exchange microcatheter includes a microcatheter body, and a rapid exchange port is provided on the side wall of the microcatheter body at a set distance from the distal end. The feature is that a soft elastic recoverable sealing film is fixedly connected to the rapid exchange port for the guide wire to pass through. After the guide wire passes through the recoverable sealing film, it is tightened by the recoverable sealing film. When the guide wire is withdrawn from the microcatheter body, the perforation of the recoverable sealing film restores the sealing of the rapid exchange port.

[0013] As a further optimized technical solution: The recoverable sealing film is made of TPU polymer material.

[0014] As a further optimized technical solution: The recoverable sealing film is an integrally formed sheet structure.

[0015] As a further optimized technical solution: The recoverable sealing film is a layered structure woven from filamentous TPU material.

[0016] As a further optimized technical solution: The microcatheter body includes an outer tube body, an intermediate tube body and an inner tube body, and the hardness of the intermediate tube body is higher than that of the outer tube body and the inner tube body.

[0017] As a further optimized technical solution: The intermediate tube body is a metal stent structure.

[0018] As a further optimized technical solution: The rapid exchange port is arranged within a range of 12 cm - 15 cm close to the distal end of the microcatheter.

[0019] As a further optimized technical solution: The thickness of the recoverable sealing film is less than the thickness of the outer tube body.

[0020] In order to achieve the above object, the stent delivery device of the present invention provides the following technical solutions:

[0021] A stent delivery device comprises an operating handle and a microcatheter, wherein the microcatheter is connected to the operating handle via a gravity tube, and a rapid exchange port is arranged near the distal end of the microcatheter, wherein the microcatheter is a rapid exchange microcatheter as described in any one of the above technical solutions.

[0022] As a further optimized technical solution: a developing ring is arranged at the end of the microcatheter body, and the developing ring is arranged on the middle layer tube body.

[0023] The quick exchange microcatheter of the present invention has the following beneficial effects: by covering the quick exchange port of the microcatheter with a soft and elastic recoverable closed membrane, it is ensured that when the guide wire is not required to enter, blood will not enter the microcatheter through the quick exchange port. In addition, the position of the quick exchange port is sealed by the recoverable closed membrane, thereby eliminating the weak link of the microcatheter. During the operation, the operator does not need to distract his attention to the condition of the microcatheter, thereby improving the efficiency of the surgical operation and reducing the surgical risk. Furthermore, since the recoverable closed membrane is soft and elastic, the guide wire will be clamped and fixed by the recoverable closed membrane after passing through the recoverable closed membrane and entering the microcatheter, thereby effectively avoiding displacement and twisting of the guide wire in the microcatheter, thereby improving the accuracy of the surgical operation.

[0024] The beneficial effects of the stent delivery device of the present invention are similar to those of the rapid exchange microcatheter and are not described in detail herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. Among them:

[0026] Figure 1 This is a schematic diagram of the overall structure of a stent delivery device according to an embodiment of the present invention;

[0027] Figure 2 for Figure 1 A magnified schematic diagram of part A;

[0028] Figure 3 This is a schematic diagram of a guide wire passing through a recoverable sealing membrane according to an embodiment of the present invention;

[0029] Figure 4 This is a schematic diagram of a delivery catheter extending into a microcatheter according to an embodiment of the present invention.

[0030] In the figure: 1. Microcatheter body; 11. Outer tube body; 12. Middle tube body; 13. Inner tube body; 2. Quick exchange port; 3. Recoverable sealing membrane; 4. Guide wire; 5. Operating handle; 6. Attraction tube; 7. Development ring; 8. Delivery catheter. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention belong to the scope of protection of the present invention.

[0032] In the description of the present invention, the orientation or positional relationship indicated by the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention rather than requiring the present invention to be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present invention. The terms "connected" and "coupled" used in the present invention should be understood in a broad sense. For example, it may be a fixed connection or a detachable connection; it may be directly connected or indirectly connected through an intermediate component. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0033] The present invention will be described in detail below with reference to the drawings and in conjunction with the embodiments. It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0034] Embodiment 1 of the stent of the stent delivery device of the present invention:

[0035] The present invention provides a stent delivery device, mainly by covering a soft elastic recoverable sealing film on the rapid exchange port on the microcatheter body, eliminating the weak link of the microcatheter itself, making the surgical operation more convenient. At the same time, the recoverable sealing film allows the guide wire to pass through, retaining the rapid exchange ability of the microcatheter, providing convenience for the surgical operation.

[0036] Specifically, as Figure 1 、 Figure 2As shown in the figure, the stent delivery device consists of an operating handle 5, a microcatheter, and a gravitational tube 6. Among them, the microcatheter is connected to the operating handle 5 through the gravitational tube 6. That is, the gravitational tube 6 serves as a connecting transition part between the operating handle 5 and the microcatheter. The handle 5 is convenient for the surgical operator to hold and grasp when twisting and delivering the microcatheter. The gravitational tube 6 is located between the microcatheter and the handle 5 and is used to bear the load of the handle 5 and transfer the load to the microcatheter. Among them, the microcatheter in this embodiment is a rapid exchange microcatheter. The rapid exchange microcatheter includes a microcatheter body 1. The end far from the surgical operator is defined as the "distal end". A rapid exchange port 2 is opened on the side wall at a set distance at the distal end of the microcatheter body 1. A soft and elastic recoverable sealing film 3 is fixedly connected to the rapid exchange port 2 for the guide wire 4 to pass through. After the guide wire 4 passes through the recoverable sealing film 3, it is tightly clamped and connected by the recoverable sealing film 3. At this time, due to the elastic characteristics of the recoverable sealing film 3, the perforation of the recoverable sealing film 3 presses the guide wire 4 circumferentially, thus playing a role in fixing the guide wire 4. In this way, during the operation, the occurrence of situations such as displacement and torsion of the guide wire 4 in the blood vessel can be effectively reduced. When the guide wire 4 is withdrawn from the microcatheter body 1, the perforation of the recoverable sealing film 3 restores to seal the rapid exchange port. To be precise, the perforation of the recoverable sealing film 3 cannot return to the state without perforation, but the perforation can return to the extent that can ensure the sealing of the rapid exchange port 2, thereby ensuring the tightness of the rapid exchange port 2 and avoiding the situation that the microcatheter enters the blood from the rapid exchange port 2.

[0037] In this embodiment, the recoverable sealing film 3 is made of TPU polymer material, and specifically, the TPU polymer material with the brand number TPU12A is selected. In this embodiment, the recoverable sealing film 3 is an integrally formed sheet structure, which is convenient for covering the rapid exchange port 2 to seal the rapid exchange port 2.

[0038] In this embodiment, the microcatheter body 1 includes an outer tube body 11, an intermediate tube body 12, and an inner tube body 13. The hardness of the intermediate tube body 12 is higher than that of the outer tube body 11 and the inner tube body 13. In order to provide better support for the microcatheter, the intermediate tube body 12 is a metal stent structure. In addition, in order to be able to effectively image to help the doctor quickly locate the position where the microcatheter arrives, a radiopaque ring 7 is provided at the end of the microcatheter body 1, and the radiopaque ring 7 is provided on the intermediate tube body 12.

[0039] In order to facilitate the passage of the guide wire 4, the thickness of the recoverable sealing film 3 is less than the thickness of the outer tube body 11.

[0040] In this embodiment, the rapid exchange port 2 is set within the range of 5 cm - 15 cm close to the distal end of the microcatheter. Compared with the prior art, the distance close to the distal end of the microcatheter is further shortened.

[0041] To avoid damaging blood vessels when the microcatheter traverses within the blood vessels, the distal end of the microcatheter is processed to be softer than the body of the microcatheter. Therefore, after the rapid exchange port 2 is opened, due to the damaged tube wall, the support performance of the distal end of the microcatheter is further reduced. To avoid deformation of the distal end of the microcatheter during the operation, the rapid exchange port 2 is opened at a rearward position. However, in the present invention, due to the presence of the recoverable sealing membrane 3, the weak link of the microcatheter itself is eliminated, and the support performance at the rapid exchange port 2 is improved. Therefore, the rapid exchange port 2 can be opened at a position closer to the distal end, so that it is more convenient for the guide wire 4 to enter and quickly guide the microcatheter to the designated position. Moreover, because the rapid exchange port 2 is closer to the distal end, the guide wire 4 will be easier to advance distally after entering the microcatheter, thus making it more convenient to guide the microcatheter to a more precise lesion location.

[0042] When the present invention is specifically used, first, the microcatheter is pushed to the vicinity of the lesion location, and then the guide wire 4 is delivered into the blood vessel. As Figure 3 shown, after the guide wire 4 reaches the vicinity of the lesion location, it penetrates through the recoverable sealing membrane 3 on the rapid exchange port 2 and enters the microcatheter, and then guides the microcatheter to the precise lesion location. Then, the guide wire 4 is withdrawn. As Figure 4 shown, the delivery catheter 8 reaches the lesion location along the microcatheter and releases the stent inside. At this time, due to the shape and flexibility of the recoverable sealing membrane 3, the recoverable sealing membrane 3 will be pushed to the outside of the microcatheter by the delivery catheter 8 at this time, without occupying the lumen of the microcatheter, leaving more room for the delivery catheter 8 and the instruments.

[0043] In other embodiments of the stent delivery device: The difference between this embodiment and Embodiment 1 is that, in Embodiment 1, the recoverable sealing membrane is made of TPU polymer material, while in this embodiment, the recoverable sealing membrane can be made of rubber material.

[0044] In other embodiments of the stent delivery device: The difference between this embodiment and Embodiment 1 is that, in Embodiment 1, the recoverable sealing membrane is an integrally formed sheet structure, while in this embodiment, the recoverable sealing membrane is a layered structure woven from filamentous TPU material. Perforations are formed between the filamentous TPU materials. Due to the good elasticity of the TPU material, the perforations remain sealed in the normal state. When the guide wire needs to pass through the recoverable sealing membrane, it can directly pass through the perforation position. Compared with the integral structure, it is more convenient for the guide wire to penetrate.

[0045] In other embodiments of the stent delivery device: The difference between this embodiment and Embodiment 1 is that in Embodiment 1, no perforation is provided on the recoverable sealing membrane, and the perforation is formed after the guide wire penetrates through. However, in this embodiment, a perforation can be reserved on the recoverable sealing membrane to facilitate the penetration of the guide wire. And due to the elastic effect of the recoverable sealing membrane, the perforation is tightened to a sealed state under normal conditions.

[0046] Embodiment 1 of the rapid exchange microcatheter of the present invention:

[0047] The specific structure of the rapid exchange microcatheter in this embodiment is the same as that of the rapid exchange microcatheter described in any one of the above embodiments, and will not be elaborated here.

[0048] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention are within the scope of protection of the pending claims of the present invention.

Claims

1. A rapid exchange microcatheter, comprising a microcatheter body (1), and a rapid exchange port (2) is provided on the side wall of the microcatheter body (1) at a set distance from the distal end position. Characterized in that, A soft and elastic recoverable sealing film (3) is fixedly connected to the rapid exchange port (2) for guiding a wire (4) to pass through. After the wire (4) passes through the recoverable sealing film (3), it is tightened by the recoverable sealing film (3) to reduce the occurrence of displacement and torsion of the wire (4) in the blood vessel; when the wire (4) is withdrawn from the microcatheter body (1), the perforation of the recoverable sealing film (3) resumes to seal the rapid exchange port (2); the rapid exchange port (2) is arranged within a range of 5 cm - 15 cm close to the distal end of the microcatheter.

2. The rapid exchange microcatheter according to claim 1, Characterized in that, The recoverable sealing film (3) is made of TPU polymer material.

3. The rapid exchange microcatheter according to claim 2, Characterized in that, The recoverable sealing film (3) is an integrally formed sheet structure.

4. The rapid exchange microcatheter according to claim 2, Characterized in that, The recoverable sealing film (3) is a layered structure woven from filamentous TPU material.

5. The rapid exchange microcatheter according to any one of claims 1 - 4, Characterized in that, The microcatheter body (1) comprises an outer tube body (11), an intermediate tube body (12) and an inner tube body (13), and the hardness of the intermediate tube body (12) is higher than that of the outer tube body (11) and the inner tube body (13).

6. The rapid exchange microcatheter according to claim 5, Characterized in that, The intermediate tube body (12) is a metal stent structure.

7. The rapid exchange microcatheter according to claim 1, Characterized in that, The thickness of the recoverable sealing film (3) is less than the thickness of the outer tube body (11).

8. A stent delivery device, comprising an operating handle (5) and a microcatheter. The microcatheter is connected to the operating handle (5) through a gravitational tube (6), and a rapid exchange port (2) is arranged at a position close to the distal end of the microcatheter. Characterized in that, The microcatheter is the rapid exchange microcatheter according to any one of claims 1 - 7.

9. The stent delivery device according to claim 8, Characterized in that, A radiopaque ring (7) is arranged at the end of the microcatheter body (1), and the radiopaque ring (7) is arranged on the intermediate tube body (12).

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