Cardiovascular interventional microdevice and processing method

Abstract

The present invention relates to a cardiovascular interventional microdevice and a processing method, comprising a strip-shaped flexible substrate, wherein a plurality of deformable plates are provided on the upper surface of the flexible substrate, the deformable plates being made of shape memory alloy material, the plurality of deformable plates being arranged in parallel and distributed along the length direction of the flexible substrate, the long axis of the deformable plates forming a set acute angle with the long axis of the flexible substrate, an electric heating circuit fixed to the flexible substrate being provided on the periphery of the region where the plurality of deformable plates are located, the electric heating circuit being used to be connected to a power source to generate heat when powered on, and the interventional microdevice of the present invention having both active guiding and thrombus removal functions.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a cardiovascular interventional microdevice and a processing method thereof. Background Art

[0002] The statements herein merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] Currently, the treatment of ischemic stroke (also known as "stroke") requires a more effective and rapid way to save patients' lives. In recent years, interventional thrombectomy technology based on medical devices such as microcatheters, microguidewires, and thrombectomy stents has been shown to have great potential in the treatment of ischemic stroke patients.

[0004] In existing cardiovascular interventional surgical devices, it is necessary to guide to the lesion location through a micro-guidewire or micro-catheter. Among them, the use of active guidewires and catheters can achieve controllable bending, avoiding the risk of cutting blood vessels due to bending due to friction with the blood vessel wall. In existing active guidewire and catheter designs, commonly used driving methods include wire drive, magnetic drive and hydraulic drive, etc., but the active catheters made based on the above methods will bend during use. In addition, when removing the thrombus, it is often necessary to fold the thrombus removal stent and embed it into the microcatheter. After it reaches the target position with the microcatheter, it is released from the microcatheter and passively unfolded with the help of its own superelasticity. The operation is complicated and the manufacturing process is complicated. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the purpose of the present invention is to provide a cardiovascular interventional microdevice that can realize active guidance and thrombus removal functions.

[0006] In order to achieve the above object, the present invention is implemented through the following technical solutions:

[0007] In the first aspect, an embodiment of the present invention provides a cardiovascular interventional microdevice, comprising a strip-shaped flexible substrate, with a plurality of deformable plates arranged on the upper surface of the flexible substrate, the deformable plates being made of shape memory alloy material, the plurality of deformable plates being arranged in parallel and distributed along the length direction of the flexible substrate, the long axis of the deformable plates forming a set acute angle with the long axis of the flexible substrate, and an electric heating circuit fixed to the flexible substrate being provided on the periphery of the area where the plurality of deformable plates are located, the electric heating circuit being used to be connected to a power source to generate heat when powered on.

[0008] Optionally, the flexible substrate is made of thermoplastic polyurethane elastomer rubber material.

[0009] Optionally, the electric heating circuit is made of an electric heating wire, and the surface of the electric heating wire is coated with an insulating layer.

[0010] Optionally, the electric heating circuit adopts a U-shaped structure, and its two ends are used to connect to the power supply.

[0011] Optionally, the outer periphery of the electric heating circuit and the deformable sheet is encapsulated by an encapsulation layer, the encapsulation layer is fixed to the upper surface of the flexible substrate, the electric heating circuit and the deformable sheet are located within the encapsulation layer, and the thickness of the encapsulation layer is greater than the thickness of the flexible substrate so that the deformable edge is offset relative to the center of the overall structure formed by the encapsulation layer and the flexible substrate.

[0012] Optionally, the encapsulation layer is made of thermoplastic polyurethane elastomer rubber.

[0013] Optionally, an interventional catheter is also included, and one end of the flexible substrate extends into the interventional catheter and is fixedly connected to the interventional catheter.

[0014] In a second aspect, an embodiment of the present invention provides a method for processing the cardiovascular intervention microdevice according to the first aspect, comprising the following steps:

[0015] preparing a flexible substrate;

[0016] Making a plurality of deformable sheets on the upper surface of the flexible substrate;

[0017] An electric heating circuit is placed on the upper surface of the flexible substrate, and the electric heating circuit is located outside the area where the multiple deformable sheets are located;

[0018] The flexible substrate is encapsulated with liquid encapsulation material to form an encapsulation layer, and the encapsulation layer encapsulates the deformable sheet and the electric heating circuit inside the encapsulation layer.

[0019] Optionally, a liquid thermoplastic polyurethane elastomer rubber material is injected into the mold, and the flexible substrate is obtained after the liquid thermoplastic polyurethane elastomer rubber material is allowed to stand for a set time and solidifies.

[0020] Optionally, a micro-sodium processing method is used to manufacture multiple deformable sheets on the surface of the flexible substrate.

[0021] The beneficial effects of the present invention are as follows:

[0022] 1. The cardiovascular interventional microdevice of the present invention has a plurality of deformable sheets arranged on a flexible substrate, wherein the long axis of the deformable sheet forms a set acute angle with the long axis of the flexible substrate, and the deformable sheet is made of a shape memory alloy material. When heated, the deformable sheet can produce heat contraction deformation, thereby causing the flexible substrate to produce bending-torsion coupling deformation, thereby realizing the steering of the flexible substrate. After the flexible substrate produces bending-torsion coupling deformation, its rigidity is increased, and thrombus removal can be performed, thereby realizing the simultaneous active guidance and thrombus removal functions, without the need for microguidewires and active catheters, avoiding the occurrence of buckling, and the surgical operation is simple and convenient. At the same time, when grabbing the thrombus, the flexible substrate and the deformable sheet are in contact with the thrombus surface, with a strong thrombus capture ability and a good thrombus removal effect.

[0023] 2. The cardiovascular intervention microdevice of the present invention is provided with an encapsulation layer to isolate the deformable sheet and the electric heating circuit from the external blood flow environment, thereby improving the safety of the electric heating drive during the cardiovascular intervention process.

[0024] 3. In the cardiovascular intervention microdevice of the present invention, the surface of the metal wire is coated with an insulating layer, thereby preventing the metal wire from short-circuiting due to contact in the distal access catheter or the suction catheter.

[0025] 4. The cardiovascular intervention microdevice of the present invention is manufactured by preparing a flexible substrate, making a deformable sheet on the surface of the flexible substrate, placing an electric heating circuit, and then packaging to complete the process. The manufacturing process is simple and convenient. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings, which constitute a part of the present invention, 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 improper limitations on the present invention.

[0027] Figure 1 This is a top view of the structure of the thrombus capture portion of Example 1 of the present invention;

[0028] Figure 2 This is a front view of the structure of the thrombus capture portion of Example 1 of the present invention;

[0029] Figure 3 This is a schematic diagram of the overall structure of Example 1 of the present invention;

[0030] Figure 4 This is a schematic diagram of the use process of Example 1 of the present invention;

[0031] Figure 5 This is a schematic diagram of the processing flow of Example 2 of the present invention;

[0032] Among them, 1. thrombus capture part, 2. interventional catheter, 3. blood vessel, 4. thrombus;

[0033] 101. Flexible substrate, 2. Deformable sheet, 103. Electric heating circuit, 104. Metal wire, 105. Encapsulation layer. DETAILED DESCRIPTION

[0034] Example 1

[0035] This embodiment provides a cardiovascular intervention micro-device, such as Figure 1-Figure 3 As shown, it includes an interventional catheter 2 and a thrombus capturing part 1 , and the thrombus capturing part 1 includes a flexible substrate 101 , a deformable sheet 102 , an electric heating circuit 103 and a packaging layer 105 .

[0036] The flexible substrate 101 adopts a strip structure, one end of the flexible substrate 101 extends into the interior of the medium catheter 2 and is fixedly connected to the interventional catheter 2. In this embodiment, the flexible substrate 101 and the interventional catheter 2 are fixed by bonding or other means. Those skilled in the art can make settings according to actual needs.

[0037] In this embodiment, the flexible substrate 101 is a strip-shaped structure, one end of which is used to connect to the interventional catheter 2, and the other end is an arc-shaped structure. The flexible substrate 101 is made of thermoplastic polyurethane elastomer rubber (TPU) material, which is thermoplastic and can shrink when heated.

[0038] The upper surface of the flexible substrate 101 has a deformation piece fixing area, and the deformation piece fixing area is provided with a plurality of deformation pieces 102. The deformation pieces 102 are in a long strip structure and are made of shape memory alloy. Preferably, the deformation pieces are made of nickel-titanium shape memory alloy.

[0039] The plurality of deformable sheets 102 are arranged in parallel and distributed along the length direction of the flexible substrate. The long axis of the deformable sheet 102 forms a set acute angle with the long axis of the flexible substrate 101 .

[0040] An electric heating circuit 103 is provided on the periphery of the fixed area of ​​the deformable plate. In this embodiment, the electric heating circuit 103 adopts a U-shaped electric heating wire. The electric heating wire is provided on the periphery of the fixed area of ​​the deformable plate. Its two ends are used to extend into the interventional catheter and are connected to a metal wire 104. It can be connected to a power source through the metal wire 104. The metal wire 104 is made of a conductive metal material. When the electric heating wire is energized, it can generate heat and then transfer the heat to the deformable plate.

[0041] In order to prevent the heating wire from short-circuiting due to contact in the distal access catheter or the suction catheter, the outer surface of the heating wire is coated with an insulating layer, which is made of an insulating material with good biocompatibility. Preferably, the insulating layer is made of silicone material.

[0042] The upper surface of the flexible substrate 101 is encapsulated by an encapsulation layer 105, and the heating wire and the deformable sheet 102 are encapsulated inside the encapsulation layer 105. The encapsulation layer 105 is made of thermoplastic polyurethane elastomer rubber (TPU) and has certain thermoplasticity. By setting the encapsulation layer, the deformable sheet and the heating wire are isolated from the external blood flow environment, thereby improving the safety of electrothermal drive during cardiovascular and cerebrovascular intervention.

[0043] The thickness of the encapsulation layer 105 is greater than that of the flexible substrate 101 , so that the deformable piece 102 is offset relative to the center of the overall structure formed by the encapsulation layer 105 and the flexible substrate 101 .

[0044] By designing the offset distance between the center of the overall structure formed by the deformable sheet 102, the encapsulation layer 105, and the flexible substrate 101, the angle between the long axis of the deformable sheet 102 and the long axis of the flexible substrate 101, and the geometric dimensions of the deformable sheet 102, the bending-torsion coupling deformation capability of the entire interventional microdevice can be adjusted, thereby meeting the functional requirements of active guidance and thrombus capture during vascular intervention.

[0045] The working process of this embodiment is:

[0046] like Figure 4 As shown, there is a thrombus in the diseased blood vessel. When the interventional catheter 2 is fed to the bifurcation of the blood vessel 3, it needs to turn. The external power supply is used to energize the heating wire. Current passes through the heating wire, generating Joule heat. The Joule heat is transferred to the multiple deformation plates 102 through heat conduction, driving the deformation plates 102 to contract, and then driving the flexible substrate 101 to produce bending and torsional deformation. The flexible substrate 101 bends and deforms into a spiral structure to complete the turning. After complete active guidance at the bifurcation of the blood vessel, it continues to move forward. Since the flexible substrate 101 becomes a spiral structure, its stiffness increases and it can be inserted into the thrombus. The flexible substrate 101 is inserted into the thrombus 4 to capture the thrombus 4, and then the thrombus 4 is removed to complete the thrombus removal process.

[0047] The interventional microdevice of this embodiment has both active guidance and thrombus removal functions, does not require the use of microguidewires and active catheters, avoids buckling, and is simple and convenient to operate. The entire device is highly functional.

[0048] Since the flexible matrix is ​​deformed into a spiral structure, it is in surface contact with the thrombus, has a strong ability to capture the thrombus, and has a good thrombus removal effect.

[0049] Example 2

[0050] This embodiment provides a method for processing the cardiovascular access microdevice described in Example 1, such as Figure 5 As shown, the following steps are included:

[0051] Step 1: Prepare a flexible substrate 101.

[0052] Liquid thermoplastic polyurethane elastomer rubber (TPU) material is injected into the mold and allowed to stand for a set time. After the thermoplastic polyurethane elastomer rubber material is solidified, the mold is removed to obtain a strip-shaped flexible substrate 101 .

[0053] Step 2: Make a plurality of deformable sheets 102 on the upper surface of the flexible substrate.

[0054] A plurality of deformable sheets 102 are deposited on the surface of the flexible substrate using a micro-nano processing technique. The micro-nano processing technique may adopt an existing process method, and its specific steps are not described in detail here.

[0055] Step 3: placing an electric heating circuit 103 on the upper surface of the flexible substrate. The electric heating circuit 103 is located outside the area where the multiple deformable sheets are located.

[0056] The electric heating circuit 103 uses a U-shaped heating wire. After the surface of the heating wire is coated with a silicone insulation layer, it is placed outside the fixed area of ​​the deformation piece on the upper surface of the flexible substrate.

[0057] Step 4: Use liquid thermoplastic polyurethane elastomer rubber material to encapsulate the upper surface of the flexible substrate 101 with the deformable sheet and the electric heating circuit 103 to make an encapsulation layer 105, encapsulate the deformable sheet 102 and the heating wire inside the encapsulation layer 105, and connect the two ends of the heating wire to the metal wire 104. The heating wire can be connected to the power supply through the metal wire.

[0058] Step 5: insert the metal wire into the medium conduit, and bond and fix the end of the flexible substrate 101 to the medium conduit 2, thereby completing the processing of the entire cardiovascular access microdevice.

[0059] The interventional device and processing method of this embodiment have a simple structure, are easy to process and manufacture, and have a high action execution rate. They integrate the functions of a micro-guidewire, a micro-catheter, and a thrombectomy device, and have obvious advantages in the functional integrated design and miniaturization of cerebrovascular interventional devices. They can meet diverse clinical application needs, rationally design and optimize the processing materials, structural dimensions, and drive design of the micro-device, and have a wide range of application scenarios.

[0060] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A cardiovascular interventional microdevice, characterized in that: The invention comprises a strip-shaped flexible substrate, the upper surface of which is provided with a plurality of deformable sheets made of a shape memory alloy material. The plurality of deformable sheets are arranged in parallel and distributed along the length direction of the flexible substrate, and the long axis of the deformable sheets forms a set acute angle with the long axis of the flexible substrate. The periphery of the region where the plurality of deformable sheets are located is provided with an electric heating circuit fixed to the flexible substrate, and the electric heating circuit is used to connect to a power source to generate heat when energized; The electric heating circuit is made of an electric heating wire, the surface of which is coated with an insulating layer; the electric heating circuit adopts a U-shaped structure, and its two ends are used to connect to a power source; the electric heating circuit and the upper periphery of the deformable sheet are encapsulated by an encapsulation layer, which is fixed to the upper surface of the flexible substrate, and the electric heating circuit and the deformable sheet are located within the encapsulation layer; The cardiovascular interventional microdevice uses an external power supply to energize the heating wire. When current passes through the heating wire, Joule heat is generated. The Joule heat is transferred to the multiple deformable sheets through heat conduction, driving the deformable sheets to contract, and then driving the flexible substrate to produce bending and torsional deformation. The flexible substrate bends and deforms into a spiral structure.

2. The cardiovascular interventional microdevice according to claim 1, characterized in that: The flexible base is made of thermoplastic polyurethane elastomer rubber material.

3. The cardiovascular interventional microdevice according to claim 1, characterized in that: The thickness of the encapsulation layer is greater than that of the flexible substrate so that the deformation edge is offset relative to the center of the integral structure formed by the encapsulation layer and the flexible substrate.

4. The cardiovascular interventional microdevice according to claim 1, characterized in that: The packaging layer is made of thermoplastic polyurethane elastomer rubber material.

5. The cardiovascular interventional microdevice according to claim 1, characterized in that: The invention also includes an interventional catheter, wherein one end of the flexible substrate extends into the interventional catheter and is fixedly connected to the interventional catheter.

6. A method for processing the cardiovascular intervention microdevice according to any one of claims 1 to 5, characterized in that: The following steps are involved: preparing a flexible substrate; Making a plurality of deformable sheets on the upper surface of the flexible substrate; An electric heating circuit is placed on the upper surface of the flexible substrate, and the electric heating circuit is located outside the area where the multiple deformable sheets are located; The flexible substrate is encapsulated with liquid encapsulation material to form an encapsulation layer, and the encapsulation layer encapsulates the deformable sheet and the electric heating circuit inside the encapsulation layer.

7. The method for processing a cardiovascular interventional microdevice according to claim 6, characterized in that: The liquid thermoplastic polyurethane elastomer rubber material is injected into the mold, and after standing for a set time and solidifying the liquid thermoplastic polyurethane elastomer rubber material, a flexible matrix is ​​obtained.

8. The method for processing a cardiovascular interventional microdevice according to claim 6, wherein: A micro-sodium processing method is used to manufacture multiple deformable sheets on the surface of a flexible substrate.

Images