CN112137780A

CN112137780A - Three-dimensional vector expansion cardiovascular stent with memory effect based on 4D printing

Info

Publication number: CN112137780A
Application number: CN202010850970.6A
Authority: CN
Inventors: 孟自力; 孟嘉天; 张志华; 章志华
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-08-21
Filing date: 2020-08-21
Publication date: 2020-12-29

Abstract

The invention discloses a three-dimensional vector expansion cardiovascular stent with a memory effect based on 4D printing, which comprises a stent body with a memory function, wherein the shape of the stent body is matched with that of the inner wall of a blood vessel; a balloon for dilating a blood vessel; the guiding tube is used for drawing the saccule and is fixedly connected with one end of the saccule; the micro guide wire is used for drawing the guide tube and is fixedly connected with one end of the guide tube, which is far away from the balloon; the stent body is made of memory alloy through 4D printing, and a drug coating layer capable of reducing thrombus formation is arranged on the outer wall of the stent body. The stent body is made of nickel-titanium memory alloy, and can automatically restore the self plastic deformation to the original shape at a certain specific temperature; the drug coating is arranged inside the stent body, so that the thrombosis can be effectively reduced; the balloon, the guide tube and the micro guide wire provide convenience for mounting the stent body; the whole device has the advantages of wear resistance, self-adjustment and long service life.

Description

Three-dimensional vector expansion cardiovascular stent with memory effect based on 4D printing

Technical Field

The invention relates to the field of cardiovascular stents, in particular to a three-dimensional vector expansion cardiovascular stent with a memory effect based on 4D printing.

Background

Cardiovascular and cerebrovascular diseases are a large group of diseases that seriously endanger human health and are called the "number one killers" of human health in developed countries. With the improvement of living standard of human body and the change of living mode, the incidence rate of cardiovascular and cerebrovascular diseases has a tendency to rise year by year, and it has become one of the leading causes of death worldwide. According to the data of the Chinese hygiene statistics in the hygiene department, the cardiovascular and cerebrovascular diseases are always the first leading cause of death in China, and account for one third of the total number of deaths caused by diseases.

The main deformation process of the intravascular stent as an important medical device in clinical application for treating cardiovascular diseases is the expansion process of the stent in blood vessels. This important deformation characteristic corresponds to and affects two different mechanical technical indicators of the stent: deformation and stress. The traditional cardiovascular stent has no self-regulation capability after being implanted into a blood vessel, has poor applicability and short service life, and brings inconvenience to patients and medical staff due to frequent replacement frequency. To solve the above problems, we improve this by proposing a three-dimensional vector-expanded cardiovascular stent with memory effect based on 4D printing.

Disclosure of Invention

In order to solve the technical problems, the invention provides the following technical scheme:

the invention provides a three-dimensional vector expansion cardiovascular stent with a memory effect based on 4D printing, which comprises a blood vessel for placing the stent; the stent body has a memory function, and the shape of the stent body is matched with that of the inner wall of the blood vessel; a balloon for dilating a blood vessel; the guiding tube is used for drawing the balloon and is fixedly connected with one end of the balloon; the micro guide wire is used for drawing the guide tube and is fixedly connected with one end of the guide tube far away from the balloon.

As a preferable technical scheme of the invention, the stent body is made of memory alloy through 4D printing, and the stent body is supported in the blood vessel in a laser cutting tubular shape.

As a preferable technical scheme of the invention, the stent body is formed by compounding a first support layer, a medicine coating layer and a second support layer, and the first support layer is of a solid structure.

As a preferable technical scheme of the invention, the second support layer is provided with a plurality of through holes for facilitating the medicine in the medicine coating layer to enter the blood vessel, and the through holes are annularly arranged on the second support layer in an array manner.

As a preferred technical solution of the present invention, a support frame is disposed between the first support layer and the second support layer, and two ends of the support frame are respectively fixedly connected to the first support layer and the second support layer.

As a preferable technical scheme of the invention, the first supporting layer, the second supporting layer and the supporting frame are all made of nickel-titanium memory alloy.

As a preferred technical scheme of the invention, the main components of the drug coating are rapamycin and paclitaxel.

As a preferable technical scheme of the invention, the thickness of the first supporting layer and the second supporting layer is 0.1-0.4 mm.

As a preferable technical scheme of the invention, the diameter of the through hole is 1-5 μm.

As a preferable technical scheme of the invention, the thickness of the support frame is 0.05-0.25 mm.

The invention has the beneficial effects that:

the stent body of the three-dimensional vector expansion cardiovascular stent with the memory effect based on 4D printing is made of nickel-titanium memory alloy, and the plastic deformation of the stent body can be automatically recovered to the original shape at a certain temperature;

secondly, a medicine coating is arranged inside the stent body, so that thrombosis can be effectively reduced;

thirdly, the stent body is installed through the balloon, the guide tube and the micro guide wire, so that the stent is fast, accurate and convenient to control;

and compared with the traditional intravascular stent, the intravascular stent has the advantages of wear resistance, corrosion resistance, self-adjustment and long service life.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic structural diagram of a memory effect three-dimensional vector expanded cardiovascular stent based on 4D printing before placement;

FIG. 2 is a schematic structural diagram of a memory effect three-dimensional vector expanded cardiovascular stent based on 4D printing according to the present invention when placed;

FIG. 3 is a schematic diagram of a 4D printing-based three-dimensional vector expanded cardiovascular stent with memory effect according to the present invention after placement;

FIG. 4 is a radial cross-section of a three-dimensional vector expanded cardiovascular stent with memory effect based on 4D printing according to the present invention;

FIG. 5 is an axial cross-section of a three-dimensional vector expanded cardiovascular stent with memory effect based on 4D printing according to the present invention;

FIG. 6 is an enlarged view of the memory effect three-dimensional vector expanded cardiovascular stent based on 4D printing of the present invention at A in FIG. 5;

in the figure: 1. a blood vessel; 2. a stent body; 21. a first support layer; 22. coating with a medicine; 23. a second support layer; 231. a through hole; 3. a support frame; 4. a balloon; 5. a guide tube; 6. a micro-guide wire.

Detailed Description

The preferred embodiments of the present invention will be described in conjunction with the accompanying drawings, and it will be understood that they are described herein for the purpose of illustration and explanation and not limitation.

Example (b): 1-3, a three-dimensional vector-expanded cardiovascular stent with memory effect based on 4D printing, comprising a vessel 1 for placing the stent; the stent body 2 has a memory function, and the shape of the stent body 2 is matched with that of the inner wall of the blood vessel 1; a balloon 4 for dilating the blood vessel 1; the guide tube 5 is used for drawing the balloon 4, and the guide tube 5 is fixedly connected with one end of the balloon 4; and the micro guide wire 6 is used for drawing the guide tube 5, and the micro guide wire 6 is fixedly connected with one end of the guide tube 5, which is far away from the balloon 4.

The mounting process of the bracket body 2 is as follows: firstly, threading a femoral artery, and feeding a guide catheter 5 and a micro guide wire 6 according to the previous radiography result; delivering the saccule 4 to the narrow part along the micro-guide wire 6, expanding the saccule 4, opening the artery narrow part, and then withdrawing the saccule 4; and thirdly, the stent body 2 is conveyed to the narrow section along the micro guide wire 6, after the position of the stent body 2 is adjusted to completely cover the narrow section, the stent body 2 is released, and the micro guide wire 6, the guide tube 5 and the saccule 4 are drawn out.

As shown in fig. 4-6, the laser pipe cutting structure 7 not only has good mechanical properties and manufacturing effect, but also saves production materials, thereby achieving multiple purposes. The stent body 2 is made of memory alloy through 4D printing, and the stent body 2 is supported in the blood vessel 1 in a laser cutting tubular shape. 4D printing is a revolutionary new technology which can enable materials to be rapidly molded without a printing machine, and the core technology is memory alloy. The memory alloy is a material capable of automatically deforming, and can be automatically folded into a corresponding shape according to product design only by being put into water without connecting any complicated electromechanical equipment.

The first support layer 21, the second support layer 23 and the support frame 3 are all made of nickel titanium memory alloy. Nitinol is a shape memory alloy, which is a special alloy that can automatically return its plastic deformation to its original shape at a certain temperature. The spring has the advantages of more than 20 percent of expansion rate, 107 fatigue lives, 10 times higher damping characteristic than that of a common spring, and better corrosion resistance than the best medical stainless steel at present, thereby meeting the application requirements of various engineering and medicine and being a very excellent functional material. The nickel-titanium memory alloy has the excellent characteristics of abrasion resistance, corrosion resistance, high damping, super elasticity and the like.

The stent body 2 is formed by compounding a first support layer 21, a drug coating layer 22 and a second support layer 23, wherein the first support layer 21 is of a solid structure. A support frame 3 is arranged between the first support layer 21 and the second support layer 23, and two ends of the support frame 3 are respectively fixedly connected with the first support layer 21 and the second support layer 23. The thickness of the first support layer 21 and the second support layer 23 is 0.1-0.4mm, and the thickness of the support frame 3 is 0.05-0.25 mm. The support frame 3 has the fixing and supporting functions, so that the connection strength of the invention can be ensured, and a gap is reserved between the two support layers to arrange the medicine coating 22.

The second support layer 23 is provided with a plurality of through holes 231 for facilitating the drug in the drug coating layer 22 to enter the blood vessel 1, the through holes 231 are arranged on the second support layer 23 in an annular array, and the diameter of the through holes 231 is 1-5 μm. With the aid of the through-holes 231, the drug of the drug coating 22 can slowly and continuously enter the blood vessel 1.

The main components of the drug coating layer 22 are rapamycin and paclitaxel. Rapamycin is a novel anti-rejection drug of macrolide, is the latest strong immunosuppressant in the world at present, and is clinically used for the anti-rejection of organ transplantation and the treatment of autoimmune diseases. Paclitaxel is extracted from bark of Pacific yew tree, is a novel anti-microtubule drug, can promote microtubule dimer to assemble into microtubules, and stabilize microtubules by interfering with de-polymerization process, thereby inhibiting normal dynamic recombination of microtubule network, resulting in cell division obstruction, and achieving anti-tumor effect. After the invention is implanted into the blood vessel 1, the components such as rapamycin, paclitaxel and the like can be released, thereby reducing the formation of thrombus and avoiding the blockage of the blood vessel 1.

The working principle is as follows: the stent body 2 is made of nickel-titanium memory alloy, and can automatically restore the self plastic deformation to the original shape at a certain specific temperature; the medicine coating 22 is arranged in the stent body 2, so that the thrombosis can be effectively reduced; in addition, the stent body 2 is installed through the saccule 4, the guide tube 5 and the micro guide wire 6, and is fast, accurate and convenient to control.

In the description of the present invention, it should be noted that the terms "vertical", "upper", "lower", "horizontal", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention.

In the description of the present invention, it should also be noted that, unless otherwise explicitly specified or limited, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art will understand that various changes, modifications and substitutions can be made without departing from the spirit and scope of the invention as defined by the appended claims. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A three-dimensional vector-expandable cardiovascular stent with memory effect based on 4D printing, comprising:

a vessel (1) for placing a stent;

the stent body (2) with a memory function, the shape of the stent body (2) is matched with that of the inner wall of the blood vessel (1);

a balloon (4) for dilating a blood vessel (1);

the guiding tube (5) is used for drawing the balloon (4), and the guiding tube (5) is fixedly connected with one end of the balloon (4);

the micro guide wire (6) is used for drawing the guide tube (5), and the micro guide wire (6) is fixedly connected with one end, far away from the balloon (4), of the guide tube (5).

2. The 4D printing-based three-dimensional vector expansion cardiovascular stent with memory effect is characterized in that:

the stent body (2) is made of memory alloy through 4D printing, and the stent body (2) is supported in the blood vessel (1) in a laser cutting tubular shape.

3. The 4D printing-based three-dimensional vector expansion cardiovascular stent with memory effect is characterized in that:

the stent body (2) is formed by compounding a first support layer (21), a medicine coating layer (22) and a second support layer (23), and the first support layer (21) is of a solid structure.

4. The 4D printing-based three-dimensional vector expansion cardiovascular stent with memory effect is characterized in that:

the second supporting layer (23) is provided with a plurality of through holes (231) which are convenient for the medicine in the medicine coating layer (22) to enter the blood vessel (1), and the through holes (231) are annularly arranged on the second supporting layer (23).

5. The 4D printing-based three-dimensional vector expansion cardiovascular stent with memory effect is characterized in that:

a support frame (3) is arranged between the first support layer (21) and the second support layer (23), and two ends of the support frame (3) are fixedly connected with the first support layer (21) and the second support layer (23) respectively.

6. The 4D printing-based three-dimensional vector expansion cardiovascular stent with memory effect is characterized in that:

the first supporting layer (21), the second supporting layer (23) and the supporting frame (3) are all made of nickel-titanium memory alloy.

7. The 4D printing-based three-dimensional vector expansion cardiovascular stent with memory effect is characterized in that:

the main components of the drug coating layer (22) are rapamycin and paclitaxel.

8. The 4D printing-based three-dimensional vector expansion cardiovascular stent with memory effect is characterized in that:

the thickness of the first supporting layer (21) and the second supporting layer (23) is 0.1-0.4 mm.

9. The 4D printing-based three-dimensional vector expansion cardiovascular stent with memory effect is characterized in that:

the diameter of the through hole (231) is 1-5 μm.

10. The 4D printing-based three-dimensional vector expansion cardiovascular stent with memory effect is characterized in that:

the thickness of the support frame (3) is 0.05-0.25 mm.