A retractable drug-infused stent system

Abstract

The present invention provides a retractable drug perfusion stent system, which belongs to the field of medical device technology, and includes: an inner tube and an outer tube slidably sleeved on the inner tube, the proximal ends of the inner tube and the outer tube are connected with a pushing device; the distal end of the inner tube has a tip; a perfusion microtube, which is spiral-shaped and has micropores; a perfusion tube; and a drug delivery device. The retractable drug perfusion stent system provided by the present invention is provided with micropores on the perfusion microtube. After the perfusion microtube reaches the lesion position, the perfusion microtube is switched from a retracted state to an expanded state. At this time, the perfusion microtube is freed from the restriction of the outer tube, and expands itself to fit with the blood vessel wall and expand the target lesion. The drug delivery device inputs the drug into the perfusion microtube through the perfusion tube, and delivers the drug to the target lesion through the micropores of the perfusion microtube. This drug perfusion stent will not remain in the body. At the same time, this method will not block blood flow, and can also continuously deliver drugs and control the drug delivery time. The entire operation process is simple and easy to operate.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a retractable drug-infused stent system. Background Art

[0002] At present, intravascular interventional treatment has become the first choice for the treatment of lower extremity arteriosclerosis obliterans. In recent years, more and more drug-containing devices have been reported for the treatment of lower extremity arteriosclerosis obliterans, such as drug-eluting stents, drug-coated stents, drug-coated balloons, etc. Compared with traditional balloon angioplasty and bare metal stents, drug-eluting stents and drug-coated balloons can effectively improve the patency rate of target lesions.

[0003] Among them, drug-eluting stents will remain in the body permanently when used, and the physiological load of lower limb arteries is complex, the stent fracture rate is high, and re-endovascular intervention is difficult and has little choice. Although drug-coated balloons can reduce the number of stent implants, the drug-coated balloons use a large amount of drugs, the drug utilization rate is low, and the drug-coated balloons need to block blood flow when dilating and administering drugs, which limits the drug-coated balloons' wall adhesion time and drug absorption rate. Summary of the invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the defects in the prior art that drug-eluting stents are easily broken when retained in the body, the drug-coated balloons require a large amount of medicine, the drug utilization rate is low, and the drug-coated balloons need to block blood flow during expansion and drug administration, which limits the adhesion time and drug absorption rate of the drug-coated balloons, thereby providing a retractable drug-infused stent system.

[0005] In order to solve the above technical problems, the present invention provides a retractable drug-infused stent system, comprising:

[0006] An inner tube and an outer tube slidably sleeved on the inner tube, wherein the proximal ends of the inner tube and the outer tube are connected with a pushing device;

[0007] The distal end of the inner tube has a tip, and the distal end of the outer tube is suitable for being arranged in contact with the tip;

[0008] The perfusion microtube is spiral-shaped, has microholes, and one end of the perfusion microtube close to the proximal end of the inner tube is fixedly connected to the inner tube, and the perfusion microtube is located at the distal end of the inner tube;

[0009] An infusion tube, which is sleeved on the inner tube and located inside the outer tube, wherein the distal end of the infusion tube is connected to the end of the infusion microtube, and the proximal end of the infusion tube extends out of the proximal end of the outer tube and is connected to a drug delivery device;

[0010] The perfusion microtube has a collapsed state in which it is closely attached to the surface of the inner tube and accommodated in the outer tube. The perfusion microtube also has an expanded state in which it is free from the restriction of the outer tube and expands on its own until it is attached to the blood vessel wall and expands to the target lesion. The pushing device is suitable for driving the inner tube and the outer tube to slide relative to each other so that the perfusion microtube can switch between the collapsed state and the expanded state.

[0011] Optionally, the pushing device includes:

[0012] a first tube seat, to which the proximal end of the inner tube is connected;

[0013] A second tube seat, the proximal ends of the outer tube and the perfusion tube are both connected to the second tube seat, and the inner tube passes through the second tube seat and is inserted into the outer tube.

[0014] Optionally, the perfusion microtube is NiTi shape memory alloy.

[0015] Optionally, the perfusion microtube is a double-helix microtube.

[0016] Optionally, the perfusion microtube is a multi-spiral microtube.

[0017] Optionally, a flushing port is further included, which is arranged on the second tube seat and is connected to the outer tube.

[0018] Optionally, a perfusion port extends out from the first tube seat, the proximal end of the perfusion tube is connected to the perfusion port, and the perfusion port is suitable for connecting to a drug delivery device.

[0019] Optionally, the diameter of the perfusion microtube ranges from 50 μm to 500 μm.

[0020] Optionally, a plurality of microholes are evenly arranged on the perfusion microtube.

[0021] The technical solution of the present invention has the following advantages:

[0022] 1. The retractable drug-perfused stent system provided by the present invention comprises an outer tube slidably sleeved on an inner tube, a perfusion microtube is connected to the inner tube, and micropores are arranged on the perfusion microtube. Before the perfusion microtube reaches the target lesion position, the perfusion microtube is in a retracted state, at which the distal end of the outer tube is in contact with the tip of the inner tube; when the perfusion microtube reaches the lesion position, the pushing device is controlled to make the inner tube and the outer tube slide relative to each other. During the sliding process of the outer tube relative to the inner tube, the outer tube gradually releases the perfusion microtube, so that the perfusion microtube switches from the retracted state to the open state. In the expanded state, the perfusion microtube is freed from the restriction of the outer tube, expands itself to fit the blood vessel wall and expand the target lesion, and the drug delivery device inputs the drug into the perfusion microtube through the perfusion tube, and delivers the drug to the target lesion through the micropores of the perfusion microtube; after the drug injection is completed, the outer tube moves forward while the outer tube slides relative to the inner tube, and the inner tube remains in position. When the perfusion microtube encounters the end of the outer tube, it is retracted into the outer tube again and enters the retracted state, and then the inner tube is pulled out, and the outer tube is moved out together with it under the action of the tip. This drug-perfused stent will not remain in the body, and at the same time, this method will not block blood flow, and can also continuously deliver drugs and control the drug delivery time. The entire operation process is simple and easy to operate.

[0023] 2. The retractable drug-infused stent system provided by the present invention comprises a pushing device including a first tube seat and a second tube seat, wherein the first tube seat is connected to the proximal end of the inner tube, and the second tube seat is connected to the proximal end of the outer tube, and mutual sliding between the inner tube and the outer tube can be achieved by controlling the first tube seat and the second tube seat.

[0024] 3. The retractable drug-perfused stent system provided by the present invention is provided with a flushing port on the second tube seat, the flushing port is connected to the outer tube, and physiological saline can be injected through the flushing port to remove air. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 A schematic structural diagram of a retractable drug-infused stent system provided in an embodiment of the present invention;

[0027] Figure 2 A first structural schematic diagram of a perfusion microtube provided in an embodiment of the present invention;

[0028] Figure 3 A second structural schematic diagram of the perfusion microtube provided in an embodiment of the present invention.

[0029] Description of reference numerals:

[0030] 1. Tip; 2. Microhole; 3. Perfusion microtube; 4. Outer tube; 5. Perfusion port; 6. Flushing port; 7. Inner tube; 8. Guide wire port; 9. First tube holder; 10. Second tube holder; 11. Perfusion tube. DETAILED DESCRIPTION

[0031] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0033] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0035] This embodiment provides a specific implementation of a retractable drug-infused stent system, such as Figure 1 and Figure 2 As shown, the pushing device includes a first tube seat 9 and a second tube seat 10, the first tube seat 9 is connected to the proximal end of the inner tube 7, the first tube seat 9 is also connected to the proximal end of the perfusion tube 11, the distal end of the perfusion tube 11 is fixed to the inner tube 7 by bundling, and the second tube seat 10 is connected to the proximal end of the outer tube 4, so that by controlling the first tube seat 9 and the second tube seat 10, the inner tube 7 and the outer tube 4 can slide relative to the inner tube 7 and the perfusion tube 11, and will not drive the perfusion tube 11 to move.

[0036] Specifically, the drug delivery device is connected to the perfusion tube 11 through the perfusion port 5, so that the drug can enter the interval between the perfusion tube 11 and the inner tube 7, and the proximal end of the perfusion microtube 3 extends into the interval between the perfusion tube 11 and the inner tube 7 through the binding portion.

[0037] In this embodiment, the proximal end of the inner tube 7 is connected to the first tube seat 9, and a tip 1 is provided at the distal end; the outer tube 4 is slidably sleeved on the inner tube 7, a perfusion microtube 3 is connected to the inner tube 7, and a microhole 2 is provided on the perfusion microtube 3, and the perfusion microtube 3 is connected to the first tube seat 9 through the spacing space between the perfusion tube 11 and the inner tube 7. Before the perfusion microtube 3 reaches the target lesion position, the perfusion microtube 3 is in a retracted state, at which time the distal end of the outer tube 4 is in contact with the tip 1 on the inner tube 7; when the perfusion microtube reaches the lesion position, the pushing device is controlled to make the inner tube 7 and the outer tube 4 slide against each other, and in the process of the outer tube 4 sliding relative to the inner tube 7, the outer tube 4 gradually releases the perfusion microtube 3, so that the perfusion microtube 3 switches from the retracted state to the expanded state, at which time the perfusion microtube 3 is freed from the restriction of the outer tube 4, and expands itself to fit with the blood vessel wall and expand the target lesion, and the drug delivery device inputs the drug into the perfusion microtube 3 through the perfusion tube 11, and delivers the drug to the target lesion through the micropores 2 of the perfusion microtube 3; after the drug injection is completed, in the process of the outer tube 4 sliding relative to the inner tube 7, the outer tube 4 moves forward, at which time the inner tube 7 keeps its position unchanged, and when the perfusion microtube 3 meets the end of the outer tube 4, it is retracted into the outer tube 4 again, entering the retracted state, and then the inner tube 7 is withdrawn, and under the action of the tip 1, the outer tube 4 is driven to move out together. This drug-perfused stent will not remain in the body. At the same time, this method will not block blood flow, and can continue to administer drugs and control the time of administration. The entire operation process is simple and easy to operate.

[0038] Specifically, the drug delivery device can be a syringe, the injection end of the syringe is connected to the perfusion port 5, and the drug is injected into the perfusion microtube 3; the drug delivery device can also be a pressure pump, the output end of the pressure pump is connected to the perfusion port 5, and the drug is input into the perfusion microtube 3 through the pressure pump, so that the drug has a certain pressure during the transportation process; the drug delivery device can also be an infusion bottle, the output end of the infusion bottle is connected to the perfusion port 5, and continuous drug delivery to the perfusion microtube 3 can be achieved; the drug delivery device can also be other devices, as long as it can be connected to the perfusion port 5 and can deliver drugs to the perfusion microtube 3.

[0039] Specifically, there is no specific requirement for the number of perfusion microtubes 3, such as Figure 2 and Figure 3As shown, the perfusion microtube 3 can be set as a single helical microtube, a double helical microtube, or a multi-helical microtube, which can be determined according to the actual drug delivery needs. The micropores 2 on the perfusion microtube 3 can be set to be evenly distributed in multiple numbers so as to evenly release the drug to the target lesion location. The drug delivery device continuously injects the drug into the target lesion location through the micropores 2 on the perfusion microtube 3.

[0040] In this embodiment, the diameter of the perfusion microtube 3 ranges from 50 microns to 500 microns, and the diameter of the micropore 2 ranges from 1 micron to 100 microns. The diameters of the perfusion microtube 3 and the micropore 2 can be selected according to actual drug administration conditions.

[0041] In this embodiment, the perfusion microtube 3 is made of NiTi shape memory alloy, which has superelasticity and shape memory properties and is in a radial expansion state at a temperature of about 37°C.

[0042] In this embodiment, a flushing port 6 is provided on the second tube seat 10, and the flushing port 6 is connected to the outer tube 4. The left end of the second tube seat is sealed and connected to the surface of the perfusion tube 11. Physiological saline can be injected into the gap between the outer tube 4 and the perfusion tube 11 through the flushing port 6 to remove the air at the target lesion location.

[0043] In this embodiment, a guide wire opening 8 is provided at the end of the first tube seat 9 , and a guide wire can be inserted into the inner tube 7 through the guide wire opening 8 .

[0044] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A retractable drug-infused stent system, characterized in that: include: An inner tube (7) and an outer tube (4) slidably sleeved on the inner tube (7), wherein the proximal ends of the inner tube (7) and the outer tube (4) are connected with a pushing device; The distal end of the inner tube (7) has a tip (1), and the distal end of the outer tube (4) is suitable for being arranged in contact with the tip (1); The perfusion microtube (3) is spiral-shaped, and a microhole (2) is provided on the perfusion microtube (3). One end of the perfusion microtube (3) close to the proximal end of the inner tube (7) is fixedly connected to the inner tube (7), and the perfusion microtube (3) is located at the distal end of the inner tube (7); an infusion tube (11) which is sleeved on the inner tube (7) and located inside the outer tube (4); the distal end of the infusion tube (11) is connected to the end of the infusion microtube (3); the proximal end of the infusion tube (11) extends out of the proximal end of the outer tube (4) and is connected to a drug delivery device; The perfusion microtube (3) has a collapsed state in which it is closely attached to the surface of the inner tube (7) and accommodated in the outer tube (4). The perfusion microtube (3) also has an expanded state in which it is free from the restriction of the outer tube (4) and expands on its own until it is attached to the blood vessel wall and expands to the target lesion. The pushing device is suitable for driving the inner tube (7) and the outer tube (4) to slide relative to each other, so that the perfusion microtube (3) is switched between the collapsed state and the expanded state.

2. The retractable drug-infused stent system according to claim 1, characterized in that: The pushing device comprises: A first tube seat (9), the proximal ends of the inner tube (7) and the perfusion tube (11) are both connected to the first tube seat (9); A second tube seat (10), the proximal end of the outer tube (4) is connected to the second tube seat (10), and the inner tube (7) and the perfusion tube (11) pass through the second tube seat (10) and are inserted into the outer tube (4).

3. The retractable drug-infused stent system according to claim 1, characterized in that: The perfusion microtube (3) is made of NiTi shape memory alloy.

4. The retractable drug-infused stent system according to claim 1, characterized in that: The perfusion microtube (3) is a double-helix microtube.

5. The retractable drug-infused stent system according to claim 1, characterized in that: The perfusion microtube (3) is a multi-helical microtube.

6. The retractable drug-infused stent system according to claim 2, characterized in that: It also comprises a flushing port (6) which is arranged on the second tube seat (10), and the flushing port (6) is in communication with the outer tube (4).

7. The retractable drug-infused stent system according to claim 2, characterized in that: An infusion port (5) extends from the first tube seat (9), the proximal end of the infusion tube (11) is connected to the infusion port (5), and the infusion port (5) is suitable for connecting to a drug delivery device.

8. The retractable drug-infused stent system according to claim 1, characterized in that: The diameter of the perfusion microtube (3) ranges from 50 micrometers to 500 micrometers.

9. The retractable drug-infused stent system according to claim 1, characterized in that: A plurality of microholes (2) are evenly arranged on the perfusion microtube (3).

Images