CN114948126A

CN114948126A - Implant delivery device for electromagnetic force-enabled grasping release within a deployment vessel

Info

Publication number: CN114948126A
Application number: CN202210581042.3A
Authority: CN
Inventors: 李亚泽; 于南星; 代欢
Original assignee: Acotec Scientific Co Ltd
Current assignee: Acotec Scientific Co Ltd
Priority date: 2022-05-26
Filing date: 2022-05-26
Publication date: 2022-08-30

Abstract

Embodiments of the present invention provide an implant delivery device for deployment of intravascular electromagnetic forces to achieve release of a grip. The device includes: a conduit member having a hollow chamber; an advancing-retracting member connected to a power source through a current path; a switching element that generates/loses a sufficient electromagnetic attractive force after energizing/de-energizing the advancing-retracting member by controlling on/off of the switching element; a grip portion coupled to the advancement-retraction member that is slidably movable within the lumen of the catheter member between a proximal first position and a distal second position. Sufficient electromagnetic attraction is generated by energizing the advancing-retracting member such that the gripping portions exert an inward gripping force to grip the implant, or sufficient electromagnetic attraction is lost after de-energizing the advancing-retracting member such that the gripping portions expand outward to release the implant.

Description

Implant delivery device for electromagnetic force-enabled grasping release within a deployment vessel

Technical Field

The present invention relates generally to medical devices and methods, and more particularly to an interventional medical device implantation device and method, and more particularly to various embodiments of an implant delivery device for deployment within a vessel that accomplishes grasping and releasing actions by electromagnetic forces.

Background

It is well known that implants such as embolization devices are increasingly used in the medical field to treat vascular diseases such as aneurysms and peripheral thrombi and other intracranial large vessel occlusions. Patients who have developed secondary acute ischemic stroke in intracranial large vessel obstructions, such as the internal carotid artery, middle cerebral artery (segments M1 and M2), basilar artery, and vertebral artery, typically require surgical embolectomy for revascularization, such as by navigated placement of an embolic device at the intracranial large vessel obstruction.

Placement of the embolic device is typically accomplished using a delivery system that directs the embolic device through the patient's vascular system to the site of the intracranial large vessel occlusion or aneurysm. Upon positioning at an occlusion of a large intracranial vessel or at an aneurysm, the embolic device is detached from the delivery system by activating the mechanical detachment mechanism.

Currently, a number of types of conventional systems for delivering and deploying embolic devices are marketed, but these conventional systems run the risk of premature or accidental release of the embolic device prior to deployment to the target site, since conventional systems typically rely solely on mechanical force to grip the implant, which is obviously not very strong and stable, see for example patent document 1 and patent document 2 given below. When based on navigation through the vascular path of a patient, the held implant is prone to inadvertent detachment or abrasion, particularly in the treatment of intracranial large vessel occlusions or cerebral aneurysms. During treatment of intracranial large vessel occlusion or cerebral aneurysms, the delivery system must navigate through a tortuous vascular pathway and often requires multiple withdrawals and deliveries by the surgeon to place the embolic device (implant) at the appropriate predetermined location within the vessel.

Accordingly, there remains a general need for improved systems and methods for delivering implants for treating vascular disease, particularly improved delivery systems that no longer rely solely on mechanical clamping forces, thereby minimizing the risk of accidental release or loss of the implant during delivery of the implant to a suitable predetermined location within a blood vessel by the improved delivery system.

Cited documents:

patent document 1, US20170209689a 1.

Patent document 2, CN 113766944A.

Disclosure of Invention

It is an object of embodiments of the present invention to provide an implant delivery device for deployment in a vessel that utilizes electromagnetic force to achieve a grasping release action, which solves the risk of accidental release or loss of the implant due to contact with the vessel wall when passing through the vessel of the human body, which is easily caused by the mere use of mechanical clamping force.

In order to solve the above technical problem, the embodiment of the present invention is implemented as follows:

in a first aspect, embodiments of the present invention provide an implant delivery device for deploying an endovascular implant, comprising: a conduit member having a hollow chamber; an advancing-retracting member having a proximal end portion and a distal end portion extending within the lumen interior of the catheter member, and the proximal end portion of the advancing-retracting member being connected to a power source by an electrical current path; a switch element disposed in a current path between the proximal end portion of the advancing-retracting member and the power source, the switch element being turned on or off to cause the advancing-retracting member to generate a sufficient electromagnetic attractive force upon energization or to cause the advancing-retracting member to lose a sufficient electromagnetic attractive force upon deenergization; and a grip portion coupled to the distal end portion of the advancing-retracting member, the grip portion being slidably movable within the lumen of the catheter member between a proximal first position and a distal second position, wherein, in the proximal first position, the switching element is turned on to cause the advancing-retracting member to generate sufficient electromagnetic attraction upon energization to allow the grip portion to apply an inward clamping force to grip the implant, and wherein, in the distal second position, the switching element is turned off to cause the advancing-retracting member to lose sufficient electromagnetic attraction upon de-energization to allow the grip portion to expand outward to release the implant.

The solution of the invention as given above (implant delivery device for deploying endovascular implants) is in a way that the mechanical clamping force is assisted by electromagnetic attraction force, which achieves that the clamping member is clamped relatively firmly before reaching the predetermined position in the vessel. While effectively releasing the clamped implant to the predetermined position by eliminating the electromagnetic attraction force when the clamping member reaches the predetermined position in the blood vessel. Therefore, compared with a pure mechanical clamping mode, the technical scheme provided by the invention can utilize the power-on/power-off of the advancing-retracting member (push lead) to generate/eliminate electromagnetic attraction force to clamp/release the implant, can simultaneously realize firm clamping and quick release on the basis of the original mechanical clamping force, and effectively avoids the risk of accidental release or loss caused by contacting with the vessel wall when the implant passes through the blood vessel of a human body.

According to some alternative embodiments of the invention, the grip is made of a material comprising a shape memory material, a ferromagnetic material.

According to the technical scheme provided by the invention, through the selection of the manufacturing materials of the clamping part, particularly the shape memory material and the ferromagnetic material, the mechanical clamping force and the magnetic attraction force can be simultaneously utilized, so that the clamping action of the clamping part is firmer and more reliable, and the obtained mechanical force is multiplied.

According to some alternative embodiments of the invention, the shape memory material comprises a nickel titanium Ni-Ti alloy; and the ferromagnetic material is selected from one or more of iron chromium cobalt, aluminum nickel cobalt, neodymium iron boron and ferrite.

According to the technical scheme provided by the invention, the components of the shape memory material and the ferromagnetic material are selected skillfully, so that on one hand, the nickel-titanium alloy can be better utilized in clinical medicine by utilizing good biocompatibility and corrosion resistance of the nickel-titanium alloy; on the other hand, the selection of a particular ferromagnetic material not only avoids the repulsive interaction with nitinol, but also ensures that the electromagnetic attraction is effectively generated relatively quickly in the energized state.

According to some alternative embodiments of the invention, the composition ratio of the shape memory material to the ferromagnetic material is from about 2:1 to about 9: 1. It is particularly preferred that the composition ratio of the shape memory material to the ferromagnetic material is about 2.75: 1.

According to the technical scheme provided by the invention, through skillfully selecting the proportion of the composition components of the shape memory material and the ferromagnetic material, a large number of experiments show that the ratio selected in such a way can better realize the generation of sufficient electromagnetic attraction force based on the size of the catheter component on the basis of maintaining sufficient mechanical clamping force.

According to some alternative embodiments of the invention, the distal end portion of the grip comprises two or more claw members; and when sufficient electromagnetic attraction is generated upon energization of the advancing-retracting member, allowing the two or more claw members to apply inward clamping force to grip the implant.

According to the present invention as set forth above, by implementing the gripping portion as, for example, a claw-type member, it is possible to better grip the implant and keep the implant inside the catheter member during delivery while avoiding an adverse touch to the inner wall of the blood vessel.

According to some alternative embodiments of the invention, the number of claw members is four; and the four claw-shaped members are identical in size and shape and are arranged in central symmetry.

According to the present invention, as described above, with four claw-shaped members arranged in central symmetry, it is possible to better grip the implant and keep it inside the catheter member during delivery without adversely touching the inner wall of the blood vessel.

According to some alternative embodiments of the invention, each of the four jaw members has a first bend and a second bend disposed in a proximal to distal direction; in the proximal first position, when the switching element is turned on to energize the advancing-retracting member to generate sufficient electromagnetic attraction to allow the gripping portion to apply an inward clamping force to grip the implant, the first bend is substantially parallel relative to the lumen of the catheter member and the second bend is bent inward at a first angle relative to the lumen of the catheter member; and, in the distal second position, when sufficient electromagnetic attraction is lost after the switch element is opened to de-energize the advancing-retracting member to allow the gripping portion to expand outwardly to release the implant, the first bend is bent outwardly at a second angle relative to the lumen of the catheter member and the second bend is substantially parallel relative to the lumen of the catheter member.

According to some alternative embodiments of the invention, the first angle is in a range of 15 degrees to 25 degrees; and, the second angle ranges from 10 degrees to 20 degrees.

According to the technical scheme provided by the invention, the first bending part and the second bending part are arranged, so that the claw-shaped component can better simulate the finger joints of human fingers, the clamping action of the claw-shaped component is closer to the mode that the human fingers take things, and the clamping action is firmer and more reliable.

According to some alternative embodiments of the invention, the implant comprises an embolic coil, a stent, an intravesicular mesh, an expansion device, a filter, a thrombectomy device, an atherectomy device, a flow repair device.

According to the technical scheme provided by the invention, the implant delivery device provided by the embodiment of the invention can be applied to a plurality of vascular interventional surgical operations and diagnoses.

In a second aspect, embodiments of the present invention also provide an implant delivery device for deploying an endovascular implant, comprising: a conduit member having a hollow chamber; an advancing-retracting member having a proximal end portion and a distal end portion extending in the lumen interior of the catheter member; a grip coupled to the distal end portion of the advancing-retracting member, the grip slidably movable within the lumen of the catheter member between a proximal first position and a distal second position, and the grip connected to a power source through an electrical current path; and the switching element is arranged in a current path between the clamping part and the power supply, and the switching element is controlled to be switched on or switched off so that the clamping part generates enough electromagnetic attraction force after being electrified or loses enough electromagnetic attraction force after being powered off. Wherein, in the proximal first position, the switching element is switched on to cause the grip portion to generate sufficient electromagnetic attraction upon energization to allow the grip portion to apply an inward clamping force to grip an implant containing ferromagnetic material, and wherein, in the distal second position, the switching element is switched off to cause the grip portion to lose sufficient electromagnetic attraction upon de-energization to allow the grip portion to expand outward to release the implant containing ferromagnetic material.

The solution of the invention as given above (implant delivery device for deploying endovascular implants) is to use electromagnetic attraction force to assist the mechanical clamping force in such a way that the clamping member is clamped relatively firmly before reaching the predetermined position in the vessel. While effectively releasing the clamped implant to the predetermined position by eliminating the electromagnetic attraction force when the clamping member reaches the predetermined position in the blood vessel. Therefore, compared with a pure mechanical clamping mode, the technical scheme provided by the invention can utilize the power-on/power-off of the clamping part to generate/eliminate electromagnetic attraction force to clamp/release the implant containing the ferromagnetic material, can simultaneously realize firm clamping and quick release on the basis of the original mechanical clamping force, and effectively avoids the risk of accidental release or loss caused by contacting with the vessel wall when the implant passes through the blood vessel of a human body. This solution is therefore particularly suitable for implants of the type such as embolic coils, stents, intracapsular meshes, stent devices, filters, thrombectomy devices, atherectomy devices, flow restoration devices, etc., which themselves comprise ferromagnetic material.

According to some alternative embodiments of the invention, the clip portion comprises a shape memory material comprising a nickel titanium Ni-Ti alloy.

According to the technical scheme provided by the invention, the nickel-titanium alloy can be better utilized in clinical medicine by skillfully selecting the composition components of the shape memory material and utilizing the good biocompatibility and corrosion resistance of the nickel-titanium alloy.

According to some alternative embodiments of the invention, the distal end portion of the grip portion comprises two or more claw members; and, when the clamping portion is energized to generate sufficient electromagnetic attraction, allowing the two or more claw members to apply inward clamping force to clamp the implant.

According to the present invention as set forth above, by implementing the gripping portion as, for example, a claw-type member, it is possible to better grip the implant and keep the implant inside the catheter member during delivery while avoiding adverse contact with the inner wall of the blood vessel.

According to some alternative embodiments of the invention, the number of claw members is four; and, the four claw-shaped members are identical in size and shape and are arranged in central symmetry.

According to some alternative embodiments of the invention, each of the four jaw members has a first bend and a second bend disposed in a proximal to distal direction; in the proximal first position, turning on the switching element to cause the clamping portion to generate sufficient electromagnetic attraction upon energization to allow the clamping portion to apply an inward clamping force to clamp an implant comprising a ferromagnetic material, the first bend being substantially parallel relative to the lumen of the catheter member and the second bend being bent inward at a first angle relative to the lumen of the catheter member; and, in the second distal position, opening the switching element to cause the grip portion to lose sufficient electromagnetic attraction after de-energizing, thereby allowing the grip portion to expand outwardly to release the implant comprising the ferromagnetic material, the first bend bends outwardly at a second angle relative to the lumen of the catheter member, and the second bend is substantially parallel relative to the lumen of the catheter member.

According to some alternative embodiments of the invention, the first angle ranges from 15 degrees to 25 degrees; and, the second angle ranges from 10 degrees to 20 degrees.

According to some alternative embodiments of the invention, the implant comprises an embolic coil, a stent, an intravesicular mesh, an expansion device, a filter, a thrombectomy device, an atherectomy device, an ambulatory repair device; and the ferromagnetic material contained in the implant is selected from one or more of iron chromium cobalt, aluminum nickel cobalt, neodymium iron boron and ferrite.

According to the technical scheme provided by the invention, the implant delivery device provided by the embodiment of the invention can be applied to a plurality of vascular interventional surgical operations and diagnoses, and particularly has better application feasibility and adaptability for the implant which contains the ferromagnetic material.

This summary is provided to introduce selected aspects and embodiments of the present invention in a simplified form and is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. The selected aspects and embodiments are presented merely to provide the reader with a brief summary of certain forms the invention might take and are not intended to limit the scope of the invention. Other aspects and embodiments of the invention are described in the detailed description section.

These and various other aspects, embodiments, features and advantages of the present invention will be better understood when the following detailed description is read in conjunction with the accompanying drawings.

Drawings

In order to more clearly illustrate the embodiments of the present invention or technical solutions in related arts, the drawings used in the description of the embodiments or related arts will be briefly described below, it is obvious that the drawings in the following description are only some embodiments described in the present invention, and other drawings can be easily obtained by those skilled in the art without inventive exercise.

Fig. 1 is a schematic view exemplarily depicting an intravascular system including an implant delivery device holding an implant body in a delivery state according to a first embodiment of the present invention;

fig. 2 is a schematic view exemplarily depicting an example of an intravascular system including an implant delivery device and an implant body separated from each other in a released state according to a first embodiment of the present invention;

fig. 3 is a schematic diagram exemplarily depicting an example of an intravascular system including an implant delivery device separated from an implant body portion in a post-release recaptured state according to a first embodiment of the present invention;

fig. 4 is a schematic view exemplarily depicting a grip portion in a delivery state according to the first embodiment of the present invention;

fig. 5 is a schematic view exemplarily depicting a grip portion in a released state according to the first embodiment of the present invention;

FIG. 6 is an enlarged schematic view exemplarily depicting details of the claw member in a delivery state according to the first embodiment of the present invention;

fig. 7 is an enlarged schematic view exemplarily depicting a detail of the claw member in a released state according to the first embodiment of the present invention;

fig. 8 is an enlarged schematic view exemplarily depicting first and second bent-over portions of the claw member in the delivery state according to the first embodiment of the present invention;

fig. 9 is an enlarged schematic view exemplarily depicting first and second bent-over portions of the claw member in the released state according to the first embodiment of the present invention;

fig. 10 is a schematic view exemplarily depicting an intravascular system including an implant delivery device holding an implant body in a delivery state according to a second embodiment of the present invention;

fig. 11 is a schematic view exemplarily depicting an example of an intravascular system including an implant delivery device and an implant body separated from each other in a released state according to a second embodiment of the present invention;

fig. 12 is a schematic view exemplarily depicting an example of an intravascular system including an implant delivery device separated from an implant body portion in a post-release recaptured state according to a second embodiment of the present invention;

fig. 13 is a schematic view exemplarily depicting a grip portion in a delivery state according to a second embodiment of the present invention;

fig. 14 is a schematic view exemplarily depicting a grip portion in a released state according to the second embodiment of the present invention;

fig. 15 is an enlarged schematic view exemplarily depicting a detail of the claw member in a delivery state according to the second embodiment of the present invention;

fig. 16 is an enlarged schematic view exemplarily depicting a detail of the claw member in the released state according to the second embodiment of the present invention;

fig. 17 is an enlarged schematic view exemplarily depicting first and second bent-over portions of the claw member in the delivery state according to the second embodiment of the present invention;

fig. 18 is an enlarged schematic view exemplarily depicting the first and second bent-over portions of the claw member in the released state according to the second embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all embodiments of the present application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The terms "first," "second," and the like in the description and in the claims of the present application are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It will be appreciated that the data so used may be interchanged under appropriate circumstances such that embodiments of the application may be practiced otherwise than as specifically illustrated or described herein, and the terms "first," "second," and the like are used generically and do not limit the number of items, e.g., a first item may be one or more than one. Further, "and/or" in the specification and claims means at least one of connected objects, a character "/" generally means that a preceding and succeeding related objects are in an "or" relationship; also, the character "-" generally indicates that the former and latter related objects are in an "and" relationship.

In the description of the embodiments of the present invention, it should be understood that the terms "center", "length", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", and the like indicate orientations and positional relationships based on those shown in the drawings, and are only for convenience of describing the embodiments of 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 and operated in a specific orientation, and thus should not be construed as limiting the embodiments of the present invention.

In the embodiments of the present invention, unless otherwise specifically stated or limited, the terms "mounted," "connected," "fixed," and the like are to be construed broadly, e.g., as meaning either a fixed connection, a detachable connection, or an integral part; the connection can be mechanical connection, electrical connection or communication; either directly or indirectly through intervening media, either internally or in any other relationship. Specific meanings of the above terms in the embodiments of the present invention can be understood by those of ordinary skill in the art according to specific situations.

In embodiments of the invention, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through intervening media. Furthermore, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely below the second feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

Important terms

First, definitions of some important terms referred to in the present application are given for convenience of description.

Interventional medical system

The interventional medical system is inserted into a human body or a natural orifice through a surgical means, and is treated or examined for a short time, and is taken out after the treatment or examination is completed.

Generally, interventional medical systems include, but are not limited to, interventional medical device examinations, interventional medical device manipulations, and interventional medical device implantations.

Intravascular system

Intravascular systems in various embodiments of the present invention refer to medical device systems that enable the implantation/deployment/placement of specific implants at specific locations within a human vessel via an interventional medical device, via the interventional medical system described above.

Interventional medical device implantation

Interventional medical device implantation refers to surgical insertion into a human or natural orifice, either entirely or partially, or in place of the upper epidermis or ocular surface, and remains in the body for at least 30 days and can only be removed by surgical or medical means. For example: bone nails, bone plates, artificial organs, heart stents, and the like.

Aneurysm

An aneurysm refers to a bulge or bump formed on the arterial wall in the brain or other location of a human body. Aneurysms, which are the manifestations of localized or diffuse dilatation or bulging of the arterial wall due to lesions or lesions of the arterial wall, can occur in any part of the arterial system, mainly represented by distending or pulsating masses, and are more common in the trunk arteries, aorta and carotid arteries of limbs.

Embolization device

Embolic devices are implants used in a typical interventional medical device implantation technique. Here, the embolization device comprises, for example, a coil, a stent, or an intracapsular mesh. As will be appreciated by those skilled in the art, the embolization device is not limited to the aspects set forth herein, but may be adapted for use with other implants of other shapes or configurations, known or unknown.

Blood vessel visualization technique

The principle that hemoglobin in blood absorbs infrared light more strongly than other tissues is utilized, near infrared light with specific wavelength is firstly projected to the surface of skin, a photosensitive element collects infrared images of the skin, the infrared images are processed into a blood vessel distribution profile map through a high-new-energy image processing chip, and then the images are clearly arranged on the surface of the skin through a micro-projection technology.

Marker substance

Navigation through tortuous vasculature is utilized with the aid of the vessel visualization techniques described above. One or more markers may be used during navigation, which may be viewed, e.g., via fluoroscopy, to assist a physician in operating the intravascular system.

Near side

The term "proximal" and grammatical equivalents thereof refer to a position, direction, or orientation toward the operator's side or the doctor's side.

Distal side

The term "distal" and grammatical equivalents thereof refer to a position, direction, or orientation away from the operator's or physician's side.

The operator is involved in the operation

The term "operator" and grammatical equivalents thereof refer to a physician, medical staff member, examination operator, etc., operating an intravascular system provided in accordance with various embodiments of the present invention.

In the following, various technical solutions in the embodiments of the present invention will be clearly and completely described with reference to the drawings in the embodiments of the present invention.

Overall system architecture

First embodiment

Fig. 1 to 3 show an example of an intravascular system 100 according to a first embodiment of the invention. In a general overview, the exemplary intravascular system 100 includes an implant 102 and an implant delivery device 120. The delivery device 120 is operable by a surgeon to deliver and deploy the implant 102 at a target site within a patient.

As shown in fig. 1-3, implant delivery device 120 generally includes an elongate catheter member 122, an elongate advancement-retraction member 124, a gripping portion 140, and a switching element SW. The grip 140 is coupled to a distal end portion of the advancement-retraction member 124, the grip 140 gripping the implant 102 during delivery and releasing the implant 102 during deployment. The grip portion 140 includes two or more claw members 142.

For example, in the delivery state shown in fig. 1, when the switching element SW is in a closed (ON) state, a current path is formed between the proximal end portion of the advancing-retracting member 124 and the external power source PW, thereby causing the advancing-retracting member 124 to form an electromagnetic attractive force. The principle and the calculation formula of the electromagnetic attraction force can be referred to "electromagnetic induction" in chapter 7 of electromagnetism and electromotics (famous autumn and the like) published by scientific publishers 2018, 11 months, and will not be described herein. In turn, the two or more claw members 142 are constrained by the electromagnetic attraction force generated by the elongated elongate advancement-retraction member 124, effecting closure of the two or more claw members 142 and applying a radially inward clamping force to the implant 102 to grasp the implant.

In the released state shown in fig. 2, at this time, the switching element SW is in an OPEN (OFF) state to form an electric current OPEN circuit (OPEN) of the proximal end portion of the advancing-retracting member 124 and the external power source PW, thereby causing the advancing-retracting member 124 to lose the electromagnetic attraction force, and accordingly, the two or more claw members 142 are no longer constrained by the elongated advancing-retracting member 124. In this manner, the two or more claw members 142 may open or spring back to their predetermined configuration, thereby allowing the implant 102 to be released or deployed at the target site.

If, through navigation or like vessel visualization techniques, the operator deems it necessary to reposition the intravascular system 100 for more accurate deployment, the switch element SW may be closed (ON) again, thereby causing the advancing-retracting member 124 to reestablish electromagnetic attraction forces, causing the grip 140 to recoat or recapture the implant 102, as shown in FIG. 3, by the reestablished electromagnetic attraction forces before the implant 102 is fully released.

As shown with reference to fig. 1-3, the elongate catheter member 122 may be a cannula, a microcatheter, or any other suitable tubular member defining a lumen. The elongated catheter member 122 may include a proximal end portion that may remain outside the patient when the intravascular system 100 is in use and may be manipulated by a user or physician. The distal end portion of the elongated catheter member 122 may be sized and dimensioned to reach a distal location in the patient's vasculature, such as at a vessel adjacent the neck of an aneurysm, a bifurcated vessel, a vessel occlusion, a stenosis, or the like. By way of example, the elongate catheter member 122 may be selected from the group consisting of a distal access catheter and accessories manufactured by Beijing deep Ruida medical technology, Inc., product registration number: national mechanical Standard 20213030986. The distal access catheter is a single lumen elongate catheter having a flexible section of a coil and a braided reinforcing section. The distal shaft portion is coated with a hydrophilic coating to reduce friction during intravascular manipulation of the catheter and to allow the catheter to better navigate the blood vessel. The catheter tip has an identification ring to facilitate visualization under fluoroscopy. The catheter tip may be pre-steam-plasticized using an attached shaping rod to help position the catheter.

With continued reference to fig. 1-3, a grip 140 may be disposed at a distal end portion of the elongate catheter member 122. Although not shown, the elongate catheter member 122 may include one or more sections or regions, each of which may have a different configuration and/or characteristics. For example, the distal end portion of the elongate catheter member 122 may include a flexible section or region, e.g., constructed from coils, to provide the appropriate bending or deflection. The flexible distal end portion will allow the intravascular system 100 to more easily navigate through tortuous regions of the human vasculature in order to reach remote locations within the patient. The proximal end portion may be constructed of a relatively hard material, such as a rigid metal, to provide structural stability and sufficient pushability. In general, the elongate catheter member 122 or a section of the elongate catheter member 122 can be constructed from a suitable metal, such as stainless steel, nickel, titanium, nitinol, a metal alloy, a biocompatible polymer, a shape memory polymer, or a combination thereof. The outer diameter of the distal end portion of the elongated catheter member 122 is generally smaller than the outer diameter of the proximal end portion of the elongated catheter member 122 in order to reduce the outer profile of the distal end portion and facilitate navigation through tortuous human vasculature. Although not shown, the elongate catheter member 122 may also include one or more markers that may be viewed, e.g., via fluoroscopy, to assist the physician in operating the intravascular system 100.

With continued reference to fig. 1-3, the elongated advancing-retracting member 124 has a proximal end portion and a distal end portion. When the intravascular system 100 is in use, the proximal end portion of the advancing-retracting member 124 can remain outside the patient's body and can be manipulated by the operator. The distal end portion of the advancement-retraction member 124 is connected with the grip 140. Alternatively, the advancing-retracting member 124 may be in the form of an elongated wire. Optionally, the advancement-retraction member 124 may include a distal tip 126, the distal tip 126 being shaped or configured as a radiused tip to make the advancement-retraction member 124 more flexible or more resistant to causing unnecessary trauma to the vessel wall. Although not shown, the distal end portion of the advancement-retraction member 124 can include a section or region configured, for example, by a coil to provide the appropriate bending or deflection. One or more markers may also be coupled to the advancing-retracting member 124 to assist the operator in operating the intravascular system 100 via fluoroscopy.

With continued reference to fig. 1-3, the proximal end portion of the advancing-retracting member 124 is connected to the external power source PW through an electric current path, and a switching element SW is further provided in the electric current path. The switching element SW is disposed in a current path between the proximal end portion of the advancing-retracting member 124 and the external power source PW, whereby the advancing-retracting member 124 is energized to generate a sufficient electromagnetic attractive force or the advancing-retracting member 124 is de-energized to lose a sufficient electromagnetic attractive force by controlling ON (ON) or OFF (OFF) of the switching element SW.

Here, as can be understood by those skilled in the art, the above-mentioned "sufficient" electromagnetic attraction force refers to a minimum newtonian force required to achieve not only a stable holding of the implant 102 by the holding portion 140 but also no accidental falling or slipping of the implant 102 during navigation through the blood vessel. The above-mentioned "sufficient" electromagnetic attraction force can be preset not only according to the experience of the operator, but also taking into account the characteristics of the implant itself to be implanted. For example, if the implant 102 body (e.g., embolic coil or metal stent) is relatively regular in shape and easy to grip, the "sufficient" electromagnetic attraction needs to be set relatively small; conversely, if the body of the implant 102 (e.g., the intracapsular mesh or filter) is irregular in shape and not easily gripped, the "sufficient" electromagnetic attraction force needs to be set relatively large. In general, the above-mentioned "sufficient" electromagnetic attraction force is generally in the range of 1N to 10N, but the various embodiments of the present invention are not limited thereto.

Specifically, the magnetic field strength H generated by the energizing wire (i.e., the clip portion 140, the coil shape and the number of turns of which are not shown) can be determined according to the following formula (1):

H＝N×I/Le (1)

where N is the number of coil turns, I is the current magnitude, and Le is the effective magnetic path length of the sample. Further, the current and the voltage have a positive correlation, and the larger the voltage is, the larger the electromagnetic attraction force is.

Here, the external power source PW may be an Alternating Current (AC) regulated power source or a Direct Current (DC) regulated power source. The external power source PW can also adjust its output voltage or output power according to actual needs. As understood by those skilled in the art, the present invention does not set any limit to the type of the external power PW. In addition, the invention does not set any limit to the position of the power PW. Generally, the power source PW is external to the intravascular system 100 and is therefore referred to as an external power source PW. However, the power source PW may also be disposed inside the intravascular system 100 according to actual needs, for example, implemented by a button cell or a lithium battery.

In addition, the switching element SW may be various common switching elements such as a logic switching element, a digital switching element, a semiconductor switching element, and the like. The switching element SW functions to close (ON) or Open (OFF) a circuit path to supply or stop supplying power to, for example, the advancing-retracting member 124. As understood by those skilled in the art, the present invention does not impose any limitation on the type of the switching element SW.

With continued reference to fig. 1-3, the clip portion 140 is typically made using a shape memory material, a ferromagnetic material, or the like. Specifically, the shape memory material comprises a nickel titanium Ni-Ti alloy; and the ferromagnetic material is selected from one or more of iron chromium cobalt, aluminum nickel cobalt, neodymium iron boron and ferrite. It is understood that, on the one hand, the good biocompatibility and corrosion resistance of nitinol can be utilized, and thus, it is better utilized in clinical medicine. On the other hand, the selection of a particular ferromagnetic material not only avoids the repulsive interaction with nitinol, but also ensures that the electromagnetic attraction is effectively generated relatively quickly in the energized state. That is, the embodiments of the present invention better consider both the memory effect of the memory metal and the electromagnetic force generated under the electromagnetic field, and can form a more effective resultant force.

In particular, it has been concluded through extensive experimentation by the present inventors that the composition ratio of the shape memory material to the ferromagnetic material is from about 2:1 to about 9: 1. Preferably, the ratio of the components of the shape memory material and the ferromagnetic material is about 2.75:1, which is particularly suitable for metal stent-type implants. By skillfully selecting the proportion of the composition of the shape memory material and the ferromagnetic material, the inventor shows through a large number of experiments that the ratio selected in this way can generate sufficient electromagnetic attraction force based on the size of the catheter member on the basis of better realizing the maintenance of sufficient mechanical clamping force.

With continued reference to fig. 1-3 and 4-5, the grip 140 may be coupled to a distal end portion of the advancement-retraction member 124. The grip 140 may be used to grasp or secure the implant 102 throughout the delivery process, or to recoat or recapture the implant 102 into the catheter member 122 for repositioning, and to release or deploy the implant 102 to a new target site after repositioning.

In particular, with continued reference to fig. 1-3 and 4-5, the grip portion 140 may be sized and/or shaped to be disposed within the elongate catheter member 122. The grip 140 may be slidably movable within the lumen of the tubular member 122. For example, grip 140 may be moved distally relative to elongate catheter member 122 by pushing distally on the advancing-retracting member 124 and/or proximally by pulling proximally on the advancing-retracting member 124. Alternatively, the grip 140 may be moved distally and/or proximally relative to the elongate catheter member 122 by pushing and/or pulling back the elongate catheter member 122. The clip portion 140 may be fixedly coupled to the advancing-retracting member 124 at a suitable location by any suitable means, such as via brazing, welding, adhesive bonding, or the like.

With continued reference to fig. 1-3 and 4-5, the distal end portion of the grip 140 includes two or more claw members 140C. Accordingly, when sufficient electromagnetic attraction is generated upon energization of the advancing-retracting member 124, two or more jaw members 140C are allowed to apply inward clamping force to clamp the implant 102.

Preferably, as shown in fig. 4 to 5, the number of the claw members 140C is four, and the four claw members 140C are identical in size and shape and are arranged in central symmetry. Of course, it will be understood by those skilled in the art that the number of claw members 140C is not limited to four, but may be three, five, or even more. In addition, the claw members 140C may be the same size or different in shape; the claw members 140C may be symmetrical or asymmetrical with respect to each other, and the embodiments of the present invention are not limited thereto.

Specifically, as shown in fig. 4 to 5, 6 to 9, each of the four claw members 140C has a first bent portion 140C1 and a second bent portion 140C2 provided in the proximal-to-distal direction. By calculation and setting in advance, the following configuration can be formed: in the proximal first position (i.e., the delivery state), when the switching element SW is turned on such that the advancing-retracting member 124 is energized to generate sufficient electromagnetic attraction force to allow the gripping portions 140 (i.e., the four jaw members 140C) to apply an inward clamping force to grip the implant 102, the first bend 140C1 is substantially parallel with respect to the lumen of the elongate catheter member 122, while the second bend 140C2 is bent inward at the first angle a with respect to the lumen of the elongate catheter member 122; also, in the distal second position (i.e., the release state), when sufficient electromagnetic attraction is lost after the switching element SW is opened to de-energize the advancing-retracting member 124 to allow the gripping portions 140 (i.e., the four jaw members 140C) to expand outwardly to release the implant 102, the first bent portion 140C1 bends outwardly at a second angle β relative to the lumen of the elongate catheter member 122, and the second bent portion 140C2 is substantially parallel relative to the lumen of the elongate catheter member 122.

Preferably, as shown in fig. 8 and 9, the first angle α ranges from 15 degrees to 25 degrees, and the second angle β ranges from 10 degrees to 20 degrees. Of course, as can be understood by those skilled in the art, the selection of the first angle α and the second angle β may be determined according to actual needs and actual application scenarios, and the embodiments of the present invention are not limited thereto.

As shown in fig. 4 to 5 and 6 to 9, the first bent portion 140C1 and the second bent portion 140C2 are provided to make the claw-shaped member 140C better simulate the finger joints of human fingers, so that the claw-shaped member 140C is closer to the way of holding things by human fingers, and the holding action is firmer and more reliable.

In addition, an insulating layer may also be provided on the outer side of the distal tip 126 of the advancement-retraction member 124, as may be desired, to avoid electrical shock due to the distal tip 126 of the advancement-retraction member 124 having left the lumen of the elongate catheter member 122 and due to residual electrical charge at the distal tip 126 when the distal tip 126 of the advancement-retraction member 124 touches the vessel wall during release of the implant 102.

Further, with continued reference to fig. 1-3 and 4-5, a mesh implant 102 is shown. Of course, the implant 102 may also include embolic coils, stents, intravesicular meshes, expansion devices, filters, thrombectomy devices, atherectomy devices, flow repair devices, and the like, as will be appreciated by those skilled in the art. That is, the implant delivery devices provided by the various embodiments of the present invention may be applied to a wide variety of vascular interventional surgical procedures and procedures.

Second embodiment

Fig. 10 to 12 show an example of an intravascular system 400 according to a second embodiment of the invention. In a general overview, the exemplary intravascular system 400 includes an implant 402 and an implant delivery device 420. The delivery device 420 is operable by an operator to deliver and deploy the implant 402 at a target site within a patient.

As shown in fig. 10-12, the implant delivery device 420 generally includes an elongate catheter member 422, an elongate advancement-retraction member 424, a clamping portion 440, and a switching element SW. The grip 440 is coupled to a distal end portion of the advancement-retraction member 424, the grip 440 gripping the implant 402 during delivery and releasing the implant 402 during deployment. The clamping portion 440 includes two or more claw members 442. It follows that the second embodiment is very similar to the first embodiment in terms of the overall architecture of the system. However, unlike the first embodiment, the current path including the switching element SW is connected to the grip portion 440, not to the elongate advancing-retracting member 424.

For example, in the delivery state shown in fig. 10, at this time, the switching element SW is in a closed (ON) state to form a current path between the proximal end portion of the clip 440 and the external power source PW, thereby causing the clip 440 to form an electromagnetic attractive force. Such an arrangement is particularly suitable for implants 402 made of metal, particularly containing ferromagnetic materials. In addition, the principle and the calculation formula of the generation of the electromagnetic attraction force can be referred to the first embodiment, and are not described herein again. Further, the implant 402 is constrained by the electromagnetic attractive force generated by the clamp 440, effecting closure of the two or more jaw members 442 and applying a radially inward clamping force to the implant 402 to grasp the implant 402.

In the released state shown in fig. 11, at this time, the switching element SW is in an OPEN (OFF) state to form a current OPEN circuit (OPEN) of the proximal end portion of the clip 440 and the external power source PW, thereby causing the clip 440 to lose the electromagnetic attractive force, and accordingly, the two or more claw members 442 are no longer restrained by the clip 440. In this manner, the two or more jaw members 442 may open or spring back to their predetermined configurations, thereby allowing the implant 402 to be released or deployed at the target site.

If, through navigation or like vessel visualization techniques, the operator deems it necessary to reposition the intravascular system 400 for more accurate deployment, the switching element SW may be closed (ON) again, thereby causing the clamp 440 to reestablish electromagnetic attraction forces, which causes the clamp 440 to recoat or recapture the implant 402 by the reestablished electromagnetic attraction forces before the implant 402 is fully released, as shown in FIG. 12.

As shown with reference to fig. 10-12, the elongate catheter member 422 may be a cannula, a microcatheter, or any other suitable tubular member defining a lumen, similar to the first embodiment. The elongate catheter member 422 may include a proximal end portion that may remain outside the patient when the intravascular system 400 is in use and may be manipulated by a user or physician. The distal end portion of the elongate catheter member 422 can be sized and dimensioned to reach a distal location in the patient's vasculature, such as at a vessel adjacent the neck of an aneurysm, a bifurcated vessel, a vessel occlusion, a stenosis, or the like. For example, the elongate catheter member 422 may be a distal access catheter and attachment manufactured by Beijing, Shendada, medical science and technology, Inc. as in the first embodiment, and will not be described in detail.

With continued reference to fig. 10-12, a grip 440 may be disposed at a distal end portion of the elongate catheter member 422. Although not shown, the elongate catheter member 422 may include one or more sections or regions, each of which may have a different configuration and/or characteristics. For example, the distal end portion of the elongate catheter member 422 may include a flexible section or region, e.g., constructed from coils, to provide the appropriate bending or deflection. The flexible distal end portion will allow the intravascular system 400 to more easily navigate through tortuous regions of the human vasculature in order to reach remote locations within the patient. The proximal end portion may be constructed of a relatively hard material, such as a rigid metal, to provide structural stability and sufficient pushability. Generally, the elongate catheter member 422 or a section of the elongate catheter member 422 can be constructed from a suitable metal, such as stainless steel, nickel, titanium, nitinol, a metal alloy, a biocompatible polymer, a shape memory polymer, or a combination thereof. The outer diameter of the distal end portion of the elongated catheter member 422 is generally smaller than the outer diameter of the proximal end portion of the elongated catheter member 422 in order to reduce the outer profile of the distal end portion and to facilitate navigation through tortuous human vasculature. Although not shown, the elongate catheter member 422 may also include one or more markers that may be viewed, e.g., via fluoroscopy, to assist the physician in operating the intravascular system 400.

With continued reference to fig. 10-12, the elongated advancing-retracting member 424 has a proximal end portion and a distal end portion. When the intravascular system 400 is in use, the proximal end portion of the advancing-retracting member 424 can remain outside the patient's body and can be manipulated by the operator. The distal end portion of the advancement-retraction member 424 is connected with the grip 440. Alternatively, the advancing-retracting member 424 may be in the form of an elongate wire. Optionally, the advancement-retraction member 424 can include a distal tip 426, the distal tip 426 being shaped or configured as a radiused tip, such that the advancement-retraction member 424 is more flexible or more resistant to unnecessary trauma to the vessel wall. Although not shown, the distal end portion of the advancement-retraction member 424 can include a section or region configured, for example, from a coil to provide suitable bending or deflection. One or more markers may also be coupled to the advancing-retracting member 424 to assist the operator in operating the intravascular system 400 via fluoroscopy.

With continued reference to fig. 10 to 12, the proximal end portion of the clip 440 is connected to the external power source PW through a current path in which a switching element SW is also provided. The switching element SW is provided in a current path between the proximal end portion of the clip 440 and the external power source PW, whereby the clip 440 generates a sufficient electromagnetic attractive force after being energized or the clip 440 loses a sufficient electromagnetic attractive force after being de-energized by controlling ON (ON) or OFF (OFF) of the switching element SW.

Here, as can be appreciated by those skilled in the art, the above-mentioned "sufficient" electromagnetic attraction force refers to a minimum newtonian force required to achieve not only a firm grip of the gripping portion 440 on the implant 402 but also no accidental detachment or slipping of the implant 402 during navigation through the blood vessel. The above-mentioned "sufficient" electromagnetic attraction force can be preset not only on the basis of the experience of the operator, but also taking into account the characteristics of the implant 402 itself to be implanted. For example, if the implant body (e.g., embolic coil or metal stent) is relatively regular in shape and easy to grip, the "sufficient" electromagnetic attraction needs to be set relatively small; conversely, if the body of the implant 402 (e.g., the intracapsular mesh or filter) is irregular in shape and not easily gripped, the "sufficient" electromagnetic attraction force needs to be set relatively large. In general, the above-mentioned "sufficient" electromagnetic attraction force is generally in the range of 1N to 10N, but the various embodiments of the present invention are not limited thereto.

Here, the selection and arrangement of the external power source PW and the switching element SW can refer to the first embodiment, and are not described herein again.

With continued reference to fig. 10-12, the clip portion 440 is typically formed from a shape memory material. Specifically, the shape memory material comprises a nickel titanium Ni-Ti alloy. It is understood that the good biocompatibility and corrosion resistance of nitinol can be utilized to better advantage in clinical medicine.

With continued reference to fig. 10-12 and 13-14, the grip 440 may be coupled to a distal end portion of the advancement-retraction member 424. The grip 440 may be used to grasp or secure the implant 402 throughout the delivery process, or to recoat or recapture the implant 402 into the catheter member 422 for repositioning, and to release or deploy the implant 402 to a new target site after repositioning.

In particular, with continued reference to fig. 10-12 and 13-14, the gripping portion 440 may be sized and/or shaped to be disposed within the elongate catheter member 422. The gripping portion 440 may be slidably movable within the lumen of the tubular member 422. For example, the grip 440 may be moved distally relative to the elongate catheter member 422 by pushing the advancing-retracting member 424 distally, and/or proximally relative to the elongate catheter member 422 by pulling the advancing-retracting member 424 proximally. Alternatively, the grip 440 may be moved distally and/or proximally relative to the elongate catheter member 422 by pushing and/or pulling back the elongate catheter member 422. The clip portion 440 may be fixedly coupled to the advancing-retracting member 424 at a suitable location by any suitable means, such as via brazing, welding, adhesive bonding, or the like.

With continued reference to fig. 10-12 and 13-14, the distal end portion of the clamp 440 includes two or more claw members 440C. Accordingly, when sufficient electromagnetic attraction is generated upon energization of the advancing-retracting member 424, two or more jaw members 440C are permitted to apply inward clamping force to clamp the implant 402.

Preferably, as shown in fig. 13 to 14, the number of the claw members 440C is four, and the four claw members 440C are identical in size and shape and are arranged in central symmetry. Of course, it will be understood by those skilled in the art that the number of claw members 440C is not limited to four, but may be three, five, or even more. In addition, the claw members 440C may or may not be identical in size and shape; the claw members 440C may be symmetrical or asymmetrical with respect to each other, and the embodiments of the present invention are not limited thereto.

Specifically, as shown in fig. 13 to 14, 15 to 18, each of the four claw members 440C has a first bent portion 440C1 and a second bent portion 440C2 disposed in the proximal-to-distal direction. By calculation and setting in advance, the following configuration can be formed: in a proximal first position (i.e., a delivery state), when the switching element SW is turned on such that the gripping portion 440 is energized to generate sufficient electromagnetic attraction force to allow the gripping portion 440 (i.e., the four jaw members 440C) to apply an inward clamping force to grip the implant 402 comprising the ferromagnetic material, the first bend 440C1 is substantially parallel with respect to the lumen of the elongate catheter member 422, and the second bend 440C2 is bent inward at a first angle a with respect to the lumen of the elongate catheter member 422; also, in the distal second position (i.e., the released state), when the switching element SW is opened such that the clamping portion 440 loses sufficient electromagnetic attraction after being de-energized, thereby allowing the clamping portion 440 (i.e., the four jaw members 440C) to expand outwardly to release the implant 402 comprising the ferromagnetic material, the first bend 440C1 bends outwardly at a second angle β relative to the lumen of the elongate catheter member 422, while the second bend 440C2 is substantially parallel relative to the lumen of the elongate catheter member 422.

Preferably, as shown in fig. 17 and 18, the first angle α ranges from 15 degrees to 25 degrees, and the second angle β ranges from 10 degrees to 20 degrees. Of course, as can be understood by those skilled in the art, the selection of the first angle α and the second angle β may be determined according to actual needs and actual application scenarios, and the embodiments of the present invention are not limited thereto.

As shown in fig. 13 to 14 and 15 to 18, the first bent portion 440C1 and the second bent portion 440C2 are provided to make the claw member 440C better simulate the knuckle of a human finger, so that the claw member 440C can be more closely clamped to the human finger, thereby making the clamping action more firm and reliable.

Further, with continued reference to fig. 10-12 and 13-14, a mesh implant 402 is shown. Of course, the implant 402 may also include embolic coils, stents, intravesicular meshes, expansion devices, filters, thrombectomy devices, atherectomy devices, flow repair devices, and the like, as will be appreciated by those skilled in the art. That is, the implant delivery devices provided by the various embodiments of the present invention may be applied to a wide variety of vascular interventional surgical procedures and procedures. In particular, in the second embodiment, the implant 402 generally comprises a ferromagnetic material, and the ferromagnetic material comprises is selected from one or more of iron chromium cobalt, aluminum nickel cobalt, neodymium iron boron, ferrite.

Various embodiments of intravascular systems and systems for deploying implants in the human body have been described. Advantageously, the implant delivery device for achieving release of the grip by electromagnetic forces within the deployment vessel provided by various embodiments of the present invention may utilize electromagnetic forces to enhance fixation of the implant during delivery. The enhanced electromagnetic clamping action of the delivery system significantly reduces the risk of accidental or premature release of the implant when the delivery system is advanced or retracted in navigating through tortuous vascular pathways in the human body.

General operational flow

In the following, a detailed operation process of the

implant delivery device

120, 420 for deploying intravascular electromagnetic force to achieve grasping release according to various embodiments of the present invention is briefly described.

In operation, the

implant

102, 402 may be preloaded within the

elongate catheter member

122, 422 using the clamping

portion

140, 440. The

implant

102, 402 and the

grip

140, 440 together may then be transferred to a microcatheter for delivery and deployment at a target site to treat a particular disease within the patient's vascular system. In embodiments for treating neurovascular conditions, such as aneurysms or for peripheral thrombectomy, a microcatheter may be introduced to a target site through a passageway, for example, in the femoral or groin region of a patient, by using an introducer cannula or guide catheter. The microcatheter may be guided to the target site by using a guide wire. The guide wire is visible via fluoroscopy, allowing the microcatheter to be reliably advanced over the guide wire to the target site.

When the target site has been reached with the tip of the microcatheter, the guide wire may be withdrawn, thereby clearing the lumen of the microcatheter. The

intravascular system

100, 400 including the

implant

102, 402 and the

implant delivery device

120, 420 in a delivery state may be placed into the proximal open end of a microcatheter and advanced through the microcatheter. Then, the electromagnetic attraction force is obtained by closing (ON) the switching element so that the corresponding component (refer to the related description of the first embodiment fig. 1 and the second embodiment fig. 10). When the

implant

102, 402 reaches the distal end of the microcatheter, the

implant

102, 402 can be deployed from the microcatheter and positioned at the target site by Opening (OFF) the switching element to cause the corresponding component to lose electromagnetic attraction (see the associated description of fig. 2 and 11 for the first embodiment). The physician may advance and retract the implant 102, 402 a number of times to obtain a desired position of the

implant

102, 402 within the vascular system (see in particular the discussion relating to fig. 3 of the first embodiment and fig. 12 of the second embodiment). When the

implant

102, 402 is satisfactorily positioned, the physician may push the elongate advancement-

retraction member

124, 424 distally, allowing the

implant

102, 402 to exit the

implant delivery device

120, 420, releasing the

implant

102, 402 at the target site. The

elongate catheter member

122, 422 may then be removed from the microcatheter, and the microcatheter may be withdrawn from the patient's vasculature.

Industrial applicability of the invention

The invention described in this specification may for example be applied in the field of medical devices, in particular interventional medical device implantation systems.

Advantageous technical effects of the various embodiments of the present invention

Compared with the prior art, the beneficial effects obtained by the various embodiments of the invention include but are not limited to:

first, according to various embodiments of the present invention, an electromagnetic attraction force is used to assist the mechanical clamping force, which results in a more secure clamping of the clamping member before reaching a predetermined location within the vessel. While at the same time being able to effectively release the clamped implant to the predetermined position by means of eliminating the electromagnetic attraction force when the clamping member reaches the predetermined position within the vessel. Therefore, compared with a simple mechanical clamping mode, the technical scheme provided by the embodiments of the invention can utilize the power-on/power-off of the advancing-retracting member (push lead) to generate/eliminate electromagnetic attraction force to clamp/release the implant, can simultaneously realize firm clamping and quick release on the basis of the original mechanical clamping force, and effectively avoids the risk of accidental release or loss caused by contacting with the vessel wall when the implant passes through the blood vessel of a human body.

Second, according to various embodiments of the present invention, by selecting the material for manufacturing the clamping portion, especially including the shape memory material and the ferromagnetic material, the mechanical clamping force and the magnetic attraction force can be utilized simultaneously, so that the clamping action of the clamping portion is more firm and reliable, and the mechanical force obtained is multiplied.

Thirdly, according to the embodiments of the present invention, by selecting the components of the shape memory material and the ferromagnetic material skillfully, on one hand, the nickel-titanium alloy can be better utilized in clinical medicine by utilizing the good biocompatibility and corrosion resistance of the nickel-titanium alloy; on the other hand, the selection of a particular ferromagnetic material not only avoids the repulsive interaction with nitinol, but also ensures that the electromagnetic attraction is effectively generated relatively quickly in the energized state. In addition, by judicious choice of the proportions of the constituents of the shape memory material and the ferromagnetic material, it has been shown through a number of experiments that the ratio so chosen is better able to achieve the generation of a sufficient electromagnetic attraction force based on the dimensions of the catheter member while maintaining a sufficient mechanical clamping force.

Fourth, according to various embodiments of the present invention, with four jaw members arranged in central symmetry, it is possible to better grip and hold the implant inside the catheter member during delivery without inadvertently touching the inner wall of the blood vessel.

Fifthly, according to the embodiments of the invention, through the arrangement of the first bending part and the second bending part, the claw-shaped member can better simulate the finger joint of a human finger, so that the clamping action of the claw-shaped member is closer to the state of taking things by the human finger, and the clamping action is firmer and more reliable.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element. Further, it should be noted that the scope of the methods and apparatuses in the embodiments of the present application is not limited to performing the functions in the order illustrated or discussed, but may include performing the functions in a substantially simultaneous manner or in a reverse order based on the functions recited, e.g., the described methods may be performed in an order different from that described, and various steps may be added, omitted, or combined. In addition, features described with reference to certain examples may be combined in other examples.

While the present embodiments have been described with reference to the accompanying drawings, it is to be understood that the present embodiments are not limited to those precise embodiments, which are intended to be illustrative rather than restrictive, and that various changes and modifications may be effected therein by one skilled in the art without departing from the scope of the appended claims.

Claims

1. An implant delivery device for deploying an endovascular implant, comprising:

a conduit member having a hollow chamber;

an advancing-retracting member having a proximal end portion and a distal end portion extending within the lumen interior of the catheter member, and the proximal end portion of the advancing-retracting member being connected to a power source by an electrical current path;

a switch element disposed in a current path between the proximal end portion of the advancing-retracting member and the power source, the switch element being turned on or off to cause the advancing-retracting member to generate a sufficient electromagnetic attractive force upon energization or to cause the advancing-retracting member to lose a sufficient electromagnetic attractive force upon deenergization; and

a grip portion coupled to the distal end portion of the advancing-retracting member, the grip portion slidably movable within the lumen of the catheter member between a proximal first position and a distal second position, wherein, in the proximal first position, the switch element is turned on to cause the advancing-retracting member to generate sufficient electromagnetic attraction upon energization to allow the grip portion to apply an inward clamping force to grip the implant, and wherein, in the distal second position, the switch element is turned off to cause the advancing-retracting member to lose sufficient electromagnetic attraction upon de-energization to allow the grip portion to expand outward to release the implant.

2. The implant delivery device of claim 1, wherein the clip is comprised of a shape memory material, a ferromagnetic material.

3. The implant delivery device of claim 2, wherein the shape memory material comprises a nickel titanium Ni-Ti alloy; and is

The ferromagnetic material is selected from one or more of iron chromium cobalt, aluminum nickel cobalt, neodymium iron boron and ferrite.

4. The implant delivery device of claim 2, wherein the composition ratio of the shape memory material and the ferromagnetic material is about 2:1 to about 9: 1.

5. The implant delivery device of claim 4, wherein the composition ratio of the shape memory material and the ferromagnetic material is about 2.75: 1.

6. The implant delivery device of any one of claims 1 to 5, wherein the distal end portion of the grip comprises two or more claw members; and is provided with

When the advancing-retracting member is energized to generate sufficient electromagnetic attraction, the two or more claw members are allowed to apply inward clamping force to grip the implant.

7. The implant delivery device of claim 6, wherein the number of claw members is four; and is

The four claw-shaped components are the same in size and shape and are arranged in a central symmetry mode.

8. The implant delivery device of claim 7, wherein each of the four claw members has a first bend and a second bend disposed in a proximal to distal direction;

in the proximal first position, when the switching element is turned on to energize the advancing-retracting member to generate sufficient electromagnetic attraction to allow the gripping portion to apply an inward clamping force to grip the implant, the first bend is substantially parallel relative to the lumen of the catheter member and the second bend is bent inward at a first angle relative to the lumen of the catheter member; and is

In the distal second position, when the switch element is opened to de-energize the advancing-retracting member and sufficient electromagnetic attraction is lost to allow the gripping portion to expand outwardly to release the implant, the first bend is bent outwardly at a second angle relative to the lumen of the catheter member and the second bend is substantially parallel relative to the lumen of the catheter member.

9. The implant delivery device of claim 8, wherein the first angle ranges from 15 degrees to 25 degrees; and is provided with

The second angle ranges from 10 degrees to 20 degrees.

10. The implant delivery device according to any one of claims 1 to 9, wherein the implant comprises an embolic coil, a stent, an intracapsular mesh, an expansion device, a filter, a thrombectomy device, an atherectomy device, an ambulatory repair device.

11. An implant delivery device for deploying an endovascular implant, comprising:

a conduit member having a hollow chamber;

an advancing-retracting member having a proximal end portion and a distal end portion extending in the lumen interior of the catheter member;

a grip coupled to the distal end portion of the advancing-retracting member, the grip slidably movable within the lumen of the catheter member between a proximal first position and a distal second position, and the grip connected to a power source through an electrical current path; and

a switching element disposed in a current path between the clamping portion and the power supply, the switching element being turned on or off to generate a sufficient electromagnetic attraction force when the clamping portion is energized or to lose the sufficient electromagnetic attraction force when the clamping portion is de-energized,

wherein, in the proximal first position, the switching element is switched on to cause the grip portion to generate sufficient electromagnetic attraction upon energization to allow the grip portion to apply an inward clamping force to grip an implant containing ferromagnetic material, and wherein, in the distal second position, the switching element is switched off to cause the grip portion to lose sufficient electromagnetic attraction upon de-energization to allow the grip portion to expand outward to release the implant containing ferromagnetic material.

12. The implant delivery device of claim 11, wherein the clip portion comprises a shape memory material.

13. The implant delivery device of claim 12, wherein the shape memory material comprises a nickel titanium Ni-Ti alloy.

14. The implant delivery device of any of claims 11-13, wherein the distal end portion of the clamp comprises two or more claw members; and is

When the clamping portion is energized, sufficient electromagnetic attraction is generated to allow the two or more claw members to apply inward clamping force to clamp the implant.

15. The implant delivery device of any of claims 11 to 14, wherein the number of claw members is four; and is

16. The implant delivery device of claim 15, wherein each of the four claw members has a first bend and a second bend disposed in a proximal to distal direction;

in the proximal first position, turning on the switching element to cause the clamping portion to generate sufficient electromagnetic attraction upon energization to allow the clamping portion to apply an inward clamping force to clamp an implant comprising a ferromagnetic material, the first bend being substantially parallel relative to the lumen of the catheter member and the second bend being bent inward at a first angle relative to the lumen of the catheter member; and is

In the distal second position, opening the switching element to cause the grip portion to lose sufficient electromagnetic attraction after being de-energized to allow the grip portion to expand outwardly to release the implant comprising the ferromagnetic material, the first bend bends outwardly at a second angle relative to the lumen of the catheter member and the second bend is substantially parallel relative to the lumen of the catheter member.

17. The implant delivery device of claim 16, wherein the first angle ranges from 15 degrees to 25 degrees; and is

The second angle ranges from 10 degrees to 20 degrees.

18. The implant delivery device according to any one of claims 11 to 17, wherein the implant comprises an embolic coil, a stent, an intracapsular mesh, an expansion device, a filter, a thrombectomy device, an atherectomy device, an ambulatory repair device; and the number of the first and second electrodes,

the implant comprises ferromagnetic materials selected from one or more of iron-chromium-cobalt, aluminum-nickel-cobalt, neodymium-iron-boron and ferrite.