Embolization device

Abstract

An embolic device is disclosed having a proximal lobe and a distal lobe connected by a bridge. The proximal lobe has a braided mesh structure with a gradually increasing diameter from a first proximal end to a first distal end. The braided mesh structure is fabricated from multiple wires and contains narrow pores that completely block the blood supply at the implantation site. The distal lobe is a braided mesh structure extending from a second proximal end to a second distal end. The second distal end has a concave configuration, which reduces the overall length of the device, thereby increasing the device's applicability to various implantation sites. The distal lobe has a larger surface area than the proximal lobe, thereby reducing the possibility of device migration and vascular recanalization.

Description

[Technical Field]

[0001] FIELD OF THE INVENTION The present invention relates to medical devices, and more particularly to embolic devices for occluding blood vessels. [Background technology]

[0002] Embolism corresponds to the accumulation of emboli in the bloodstream. Embolism can be natural or artificially induced therapeutically. Artificially induced embolism, or therapeutic embolism, is used as a hemostatic treatment for bleeding or as a treatment for some types of cancer by intentionally blocking blood vessels to starve tumor cells.

[0003] One method of artificially inducing embolism is the use of an embolic device / occluder. An embolic device is a biomedical device that creates an obstruction within the vasculature to block the blood flow pathway. The embolic device fits within the target vessel and completely blocks the blood flow pathway, thereby useful for treating a variety of conditions, including aneurysms, left atrial appendages, atrial septal defects, fistulas, patent foramen ovale, patent ductus arteriosus vascular shutdown, or occlusion within the peripheral vasculature.

[0004] Since the advent of embolic devices, many embolic device structures have been devised. However, none of the existing embolic devices have been effective enough to firmly anchor the device at the implantation site and occlude the blood vessel by inducing embolism. For example, U.S. Pat. No. 10,470,773 discloses a vascular occluder including a single lobe. The single-lobed occluder serves both functions: to anchor the occluder at the implantation site and to embolize the device by completely blocking blood flow at the implantation site. However, due to its single-lobe structure, the device of this application takes a long time to completely block blood flow at the implantation site, thereby failing to provide immediate hemostatic treatment to the patient. Furthermore, such devices are also associated with problems related to positional controllability, as the operator does not adequately grasp the device during implantation due to the device's structure.

[0005] Furthermore, embolic devices with multiple lobes are also known. For example, the embolic devices disclosed in U.S. Patent Nos. 10,624,619 and 8,313,505 include a multilayer braided structure with a dual-lobe structure. The dual-lobe structure takes the form of a dumbbell with two similar sections at both the proximal and distal ends that extend circumferentially. However, the presence of lobes with the same shape as those included in the devices of the aforementioned publications is associated with various issues. The most important issue is the inability to completely block blood flow at the implantation site, and the high possibility of device migration, which can cause heart failure and pulmonary vascular disease.

[0006] Furthermore, few conventional embolic devices have three or more lobes. However, such devices with multiple lobes typically require a larger French size of the delivery catheter. The use of a larger catheter size makes delivery of the embolic device extremely difficult, especially in infants with congenital anomalies. This limits the applicability of existing embolic devices. Furthermore, the multi-lobe structure of conventional devices increases the length of the device, thereby limiting its deployment in limited blood vessels. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] U.S. Patent No. 10,470,773 [Patent Document 2] U.S. Patent No. 10,624,619 [Patent Document 3] U.S. Patent No. 8,313,505 Summary of the Invention [Problem to be solved by the invention]

[0008] Therefore, an embolization device needs to be devised that addresses the aforementioned shortcomings.

[0009] Although specific embodiments of the present disclosure will be described herein below with reference to the accompanying drawings, it should be understood that the disclosed embodiments are merely illustrative of the present disclosure, which may be embodied in various forms. Well-known functions and structures will not be described in detail so as not to obscure the present disclosure. Therefore, the details of the specific structure and function disclosed herein should not be construed as limiting, but as a basis for the claims and as a representative basis for teaching those skilled in the art to variously use the present disclosure in almost any appropriately detailed structure. [Means for solving the problem]

[0010] The present invention relates to an embolization device (or devices). The device is disclosed to include a binary lobe structure having a proximal lobe and a distal lobe connected by a bridge. The proximal lobe has a braided mesh structure with a gradually increasing diameter from a first proximal end to a first distal end (or a gradually decreasing diameter from the first distal end to the first proximal end). The braided mesh structure is fabricated from multiple wires and includes narrow pores that completely block the blood supply at the implantation site.

[0011] The distal lobe is a braided mesh structure extending from the second proximal end to the second distal end. The second distal end has a concave configuration that reduces the overall length of the device, thereby increasing the applicability of the device to various implantation sites. The distal lobe has a larger surface area than the proximal lobe, thereby reducing the possibility of device migration and vascular recanalization.

[0012] The foregoing and other features and advantages of the present invention will become more apparent from the following detailed description which proceeds with reference to the accompanying drawings.

[0013] The foregoing summary, as well as the following detailed description of exemplary embodiments, will be better understood when read in conjunction with the accompanying drawings. For the purpose of illustrating the disclosure, exemplary structures of the disclosure are shown in the drawings. However, the disclosure is not limited to the particular methods and instrumentalities disclosed therein. Moreover, those skilled in the art will appreciate that the drawings are not drawn to scale. [Brief explanation of the drawings]

[0014] [Figure 1a] 1A and 1B illustrate an embolic device 100 in a delivery configuration according to one embodiment of the present invention. [Figure 1b] 1A and 1B illustrate an embolic device 100 in a deployed configuration, according to one embodiment of the present invention. [Figure 2] 1 is a diagram illustrating an embolization device 100 according to one embodiment of the present invention. [Figure 2a] 1 is a diagram illustrating a distal portion of an embolic device 100 according to one embodiment of the present invention. [Figure 2b] FIG. 1 illustrates a jacket 105 of an embolic device 100 according to one embodiment of the present invention. [Figure 3] FIG. 2 shows an embolic device 100 connected to a delivery wire "w" and a delivery catheter 200 according to one embodiment of the present invention. [Figure 3a] 1 illustrates a delivery wire "w" according to one embodiment of the present invention. [Figure 3b] FIG. 1 illustrates a delivery wire "w" according to one embodiment of the present invention. [Figure 4] 1A-1C illustrate a process for manufacturing an embolic device 100 according to one embodiment of the present invention. [Figure 4a] FIG. 3 shows a mold 300 used for shape setting according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0015] Before describing the present invention in detail, definitions of certain words or phrases used throughout this patent document are provided as follows: the terms "include" and "comprise," and derivatives of these terms, mean an open-ended inclusion; the term "or" is inclusive and / or; and the terms "coupled with" and "associated therewith," and derivatives of these terms, can mean "including," "contained within," "interconnected with," "contains," "contained within," "connected to or connected with," "coupled to," "communicate with," "cooperate with," "interleave with," "juxtapose," "proximate to," "bound to or with," "having the characteristics of," and the like. Definitions of certain words and phrases are provided throughout this patent document, and those skilled in the art will understand that such definitions will in many, if not most, cases apply to prior and future uses of such defined words and phrases.

[0016] References throughout this specification to "one embodiment," "an embodiment," or similar language mean that a particular feature, structure, or characteristic described in connection with that embodiment is included in at least one embodiment. Thus, throughout this specification, appearances of the phrases "in one embodiment," "in an embodiment," and similar language do not necessarily all refer to the same embodiment and may mean "one or more embodiments, but not all embodiments," unless expressly specified otherwise. The terms "including," "comprising," "having," and variations thereof mean "including but not limited to," unless expressly specified otherwise. An enumerated list of items does not imply that any or all of the items are mutually exclusive and / or mutually inclusive, unless expressly specified otherwise. The terms "a," "an," and "the" also refer to "one or more," unless expressly specified otherwise.

[0017] Although the operations of exemplary embodiments of the disclosed methods may be described in a sequential order for convenience of presentation, it should be understood that the disclosed embodiments may encompass orders of operations other than the specific, disclosed sequential order. For example, operations described sequentially may in some cases be rearranged or performed simultaneously. Moreover, descriptions and disclosures provided with respect to one particular embodiment are not limited to that embodiment but may apply to any embodiment disclosed herein. Moreover, for simplicity, the accompanying figures may not show the various ways in which the disclosed systems, methods, and apparatuses can be used in combination with other systems, methods, and apparatuses.

[0018] Furthermore, the described features, advantages, and characteristics of the embodiments may be combined in any suitable manner. Those skilled in the art will recognize that embodiments may be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in particular embodiments that may not be present in all embodiments. These features and advantages of the embodiments will become more fully apparent from the following description and appended claims, or may be learned by practicing the embodiments as described herein below.

[0019] The present invention discloses an embolic device that can be implanted at an implantation site in the form of a blood vessel segment placed within a blood vessel within a patient's body. The embolic device of the present invention serves to occlude a blood flow pathway at the implantation site, thereby treating a predefined vascular defect. The embolic device of the present invention can effectively treat arterial-venous malformations, aneurysms, fistulas, and other vascular defects.

[0020] The embolic device of the present invention is a self-expanding device having two lobes, a proximal lobe located toward the proximal end of the device and a distal lobe located toward the distal end of the device, the proximal end of the device corresponding to the end that extends away from the operator and the distal end corresponding to the end that is located toward the operator and that is attached to a delivery wire.

[0021] The proximal and distal lobes are separated by a bridge, which is two separate structures that provides flexibility and indestructibility during the post-deployment and / or pre-deployment process.

[0022] The embolic device is implanted with the proximal lobe facing the blood flow path, i.e., positioned against the blood flow, and the distal lobe facing away from the blood flow path, i.e., positioned with the blood flow. Thus, the proximal lobe serves to promote early embolization, and the distal lobe serves to reduce migration of the embolic device from the implantation site and to support the device during and after implantation.

[0023] The proximal and distal lobes each comprise a braided mesh structure having a predefined linear density and diameter to provide flexibility to the device and also to allow the device to be easily pushed with a required radial strength during and after implantation.

[0024] The proximal lobe comprises a conical structure made of a dense mesh structure with gradually increasing diameter and pore size. The increased density of the braided mesh structure of the proximal lobe leads to a decreased porosity, which helps to completely block the passage of blood at the implantation site.

[0025] On the other hand, the mesh structure of the distal lobe is cylindrical in shape, which helps achieve better engagement with the vessel segment at the implantation site, thereby minimizing the possibility of device migration from the implantation site.

[0026] A polymer membrane is disposed inside the distal lobe, providing faster embolization than conventional systems. The polymer membrane helps reduce and mitigate the possibility of continued blood flow after occlusion by the proximal lobe. Additionally, the embolic device has two or more radiopaque markers on both lobes to aid in device positioning and observation during and after the deployment procedure. Due to the above structure, the embolic device of the present invention has a larger surface contact area than conventional systems, which further enhances the grip of the embolic device during implantation, overcoming issues related to position controllability with improved flexibility and controlled delivery.

[0027] The embolic device is delivered using a small French size (5-9 Fr) of delivery catheter, thereby eliminating the existing problem of applicability of the embolic device in infants or in limited vasculature.

[0028] The embolic devices of the present invention are constructed using a predefined method that provides the embolic device with sufficient mechanical properties such as greater flexibility, kink resistance, low crimp profile, easy deployment, and leak resistance.

[0029] Referring now to the figures, Figures 1a, 1b, and 2 disclose an embolic device 100 (or device 100) of the present invention. The embolic device 100 is a self-expanding device having a delivery configuration (Figure 1a) and a deployed configuration (Figure 1b). The delivery configuration corresponds to a configuration in which the embolic device 100 is in a compressed state for delivery at an implantation site. In the compressed state, the embolic device 100 is in a generally linear configuration and is disposed within a delivery catheter 200, as shown in Figure 1a.

[0030] The deployed configuration corresponds to a configuration in which the embolic device 100 is in an expanded state and implanted at the implantation site. In the deployed configuration, the embolic device 100 expands from a generally linear configuration to a three-dimensional expanded configuration, as shown in FIG. 1b. In the deployed configuration, the embolic device 100 blocks / restricts blood flow through blood vessels at the implantation site. The blood vessels at the implantation site may include peripheral arteries, pulmonary arteries, splenic arteries, portal vein, internal iliac arteries, arteriovenous insufficiency, arteriovenous fistulas, etc.

[0031] Embolic device 100 is deployed at the implantation site so that the longitudinal axis of embolic device 100 is aligned with the axis of the vessel segment of the blood vessel into which embolic device 100 is inserted.

[0032] To tightly engage the lumen of the vessel segment of the blood vessel at the implantation site, the embolic device 100 has a maximum expanded diameter that is slightly larger (approximately 30-50%) than the diameter of the lumen of the vessel segment of the blood vessel at the implantation site. Selecting such a maximum expanded diameter of the embolic device 100 helps to securely position the embolic device 100 relative to the lumen of the vessel segment at the implantation site. At the same time, such an optimized maximum expanded diameter of the device 100 prevents any damage to the inner lining of the blood vessel or any bulging of the outer lining of the blood vessel.

[0033] Embolic device 100 is preferably longer along its axis than its maximum expanded diameter, as shown in Figure 1b. These dimensions of device 100 substantially prevent embolic device 100 from rotating within the lumen at any angle relative to its longitudinal axis, thereby preventing embolic device 100 from dislodging along the blood vessel segment at the implantation site. The inability of embolic device 100 to rotate helps to keep embolic device 100 precisely deployed at the implantation site.

[0034] As seen in Figure 1b, when deployed, embolic device 100 engages the lumen of the blood vessel segment at the implantation site at two spaced apart positions, said positioning being a result of the structure of device 100.

[0035] Embolic device 100 extends from a proximal end 100a to a distal end 100b of device 100, thereby defining a longitudinal axis "L" of embolic device 100. Embolic device 100 includes various components aligned with longitudinal axis "L." Embolic device 100 can include one or more of a body 101, a proximal tube 103, and a distal tube (not shown) covered by a jacket 105.

[0036] The body 101 of the embolic device 100 is in the form of a hollow structure defined by at least two lobes and a bridge 101c. Each of the lobes of the present invention is in the form of a braided mesh structure made from a plurality of wires. The braided mesh structure significantly increases the density of the wires, thereby reducing the stiffness of the embolic device 100 and providing the ability for the embolic device 100 to assume a smaller outer diameter each time it is longitudinally stretched.

[0037] The mesh structure of the lobes has a predefined linear density and linear diameter selected to provide flexibility to the device 100 while also allowing the device 100 to be easily pushed with the required radial strength during and after implantation.

[0038] The mesh structure of the lobes may be formed from a biologically compatible and / or biologically degradable material, such as, without limitation, Nitinol or Poly-L-Lactide (PLLA), hi one embodiment, the mesh structure of the lobes is made from Nitinol.

[0039] The lobes can be structurally the same as or different from one another (i.e., in shape and size). In one embodiment, the lobes are separate and distinct from one another.

[0040] As one illustrative example, the embolic device 100 includes a binary lobe structure having a proximal lobe 101 a and a distal lobe 101 b. As the names suggest, the proximal lobe 101 a is located at the proximal end 100 a of the device 100, and the distal lobe 101 b is located at the distal end 100 b of the device 100.

[0041] The proximal lobe 101 a and the distal lobe 101 b each have a different shape and size. The aforementioned binary lobe structure provides the embolic device 100 with the flexibility and mechanical strength to effectively resist blood flow within the swollen capillaries at the implantation site. Due to the binary lobe structure having distinct shapes and sizes, the problems of shifting and complete blockage of blood flow are addressed individually by each of the two lobes (discussed in more detail below).

[0042] 2, the proximal lobe 101a comprises a cone-shaped braided mesh structure extending from a first proximal end a1 to a first distal end a2. It should be noted that although the present invention is described as a cone-shaped proximal lobe 101a, other shape possibilities, such as spherical, concave, flattened oval, etc., are within the scope of the present invention.

[0043] The conical shape of the proximal lobe 101a resists blood flow within the blood vessel at the implantation site, diverting the blood to other capillaries.

[0044] Due to the conical shape, the proximal lobe 101a includes a diameter that gradually decreases from the first distal end a2 to the first proximal end a1 (or a diameter that gradually increases from the first proximal end a1 to the first distal end a2). In one embodiment, the diameter of the proximal lobe 101a can range from 4 mm to 20 mm. The proximal lobe 101a has a predefined length that ranges from 4 mm to 9 mm.

[0045] The mesh structure of the proximal lobe 101a may be fabricated from multiple braided wires in a coil-forming arrangement. In one embodiment, the proximal lobe 101a is comprised of multiple layers of braided wires, resulting in the formation of narrow pores of varying sizes. The pore size of the braided mesh structure may gradually decrease from the first distal end a2 to the first proximal end a1 and may range from 1 to 200 microns. The presence of narrow pores of varying sizes helps to direct blood into different capillaries to completely cut off the blood supply at the implantation site, while also preventing dislodgement of the embolic device 100. Thus, the narrow pores of the proximal lobe 101a resist blood flow and improve the filtering properties of the embolic device 100. Furthermore, the narrow pores of the proximal lobe 101a help create a wall that resists the forces created by blood flow at the implantation site.

[0046] The first proximal end a1 may be disposed adjacent to the proximal tube 103 that marks the proximal end 100a of the device 100. The first distal end a2 may be disposed facing the distal lobe 101b and adjacent to the bridge 101c.

[0047] 2, the distal lobes 101b have a cylindrically shaped braided mesh structure, however, it should be noted that the possibility of having distal lobes 101b of other shapes, such as spherical, concave, flattened oval, etc., is also within the scope of the present invention.

[0048] The cylindrical shape of distal lobe 101 b allows embolic device 100 to properly connect to the lumen of the blood vessel segment at the implantation site while absorbing forces exerted by proximal end 100 a of embolic device 100 .

[0049] Also, as a result of the cylindrical shape, the distal lobe 101b has a larger surface area than the proximal lobe 101a. The larger surface area of ​​the distal lobe 101b allows the embolic device 100 to better fit within the blood vessel segment at the implantation site, thereby reducing the likelihood of migration and recanalization of the embolic device 100.

[0050] The distal lobe 101b can have a uniform diameter and a predefined length. The diameter of the distal lobe 101b can range from 4 mm to 20 mm. The distal lobe 101b can be expandable up to 4 mm to 9 mm. The length of the distal lobe 101b can be equal to or slightly longer than the length of the proximal lobe 101a. The length of the distal lobe 101b can range from 4 mm to 9 mm. Having approximately equal lengths for both the proximal lobe 101a and the distal lobe 101b facilitates easy molding of the device 100 when manufacturing the device 100.

[0051] The distal lobe 101b extends from a second proximal end b1 to a second distal end b2. The second proximal end b1 is disposed adjacent to the bridge 101c and faces the first distal end a2 of the proximal lobe 101a. The second distal end b2 of the distal lobe 101b is disposed adjacent to the jacket 105.

[0052] 2a, the second proximal end b1 is flat, while the second distal end b2 of the distal lobe 101b has a cup-shaped or concave configuration. The cup-shaped or concave configuration of the second distal end b2 helps reduce the overall length of the device 100, thereby allowing the device 100 to be more easily implanted at the edge of a vessel, thereby increasing the range of vessels in which the device 100 can be implanted.

[0053] Due to the aforementioned cup-shaped configuration, the distal lobe 101b at the second distal end b2 includes a recess having a depth "d" in the range of 0.1 mm to 2 mm.

[0054] The distal lobe 101b can house a flexible membrane (not shown). The flexible membrane can help embolize blood flow and initiate the endothelialization process for complete (sufficient) embolization. The flexible membrane can be made of polyethylene terephthalate (PET), expanded polytetrafluoroethylene (ePTFE), polyurethane, metallic materials, extracellular matrix, synthetic bioabsorbable polymer scaffolds, etc. In one embodiment, the flexible membrane is made of PET.

[0055] The dimensions of the flexible membrane can depend on the dimensions of the distal lobe 101b. For example, the diameter of the flexible membrane is the same as the diameter of the distal lobe 101b. The flexible membrane can include a predefined thickness ranging from 10 to 150 μm. The weight of the flexible membrane can range from 10 GSM to 40 GSM.

[0056] The flexible membrane can have the ability to expand and contract depending on the configuration of embolic device 100. For example, as embolic device 100 expands from the delivery configuration to the deployed configuration, the flexible membrane also tends to expand. In one embodiment, the flexible membrane expands in a direction non-perpendicular to the longitudinal axis "L" of embolic device 100. In an alternative embodiment, the flexible membrane expands in a circular direction substantially perpendicular to the longitudinal axis "L" of embolic device 100.

[0057] The distance separating the proximal lobe 101a and distal lobe 101b described above may vary depending on the size of the vessel (implantation site) in which the embolic device 100 is to be deployed.

[0058] In addition to the above, one or more radiopaque markers may be placed on the proximal lobe 101 a and / or distal lobe 101 b to assist the physician in efficiently orienting the embolic device 100. The radiopaque markers may take the form of radiopaque platinum wire or platinum-iridium markers attached to the mesh structure of the proximal lobe 101 a / distal lobe 101 b in a manner such that the radiopaque markers do not interfere with the expansion or contraction of the braid. Other materials, such as stainless steel, nitinol, tantalum, etc. may also be used.

[0059] The proximal lobe 101a and distal lobe 101b are connected using a bridge 101c. The bridge 101c extends from a first distal end a2 of the proximal lobe 101a to a proximal end b1 of the distal lobe 101b. The bridge 101c takes the form of a short cylindrical section, as shown in FIG. 2 . However, other shapes and configurations of the bridge 101c are within the scope of the present invention. The bridge 101c plays a major role in the contraction and expansion of the embolic device 100 and provides mechanical strength and flexibility to the proximal lobe 101a and distal lobe 101b. Additionally, because the bridge 101c connects the proximal lobe 101a and distal lobe 101b, the bridge 101c helps relieve pressure when loading the embolic device 100 into a loader. The bridge 101c provided during the free time during loading helps in expanding and contracting the device 100 during loading and unloading, thereby reducing the manual effort of loading.

[0060] 1, proximal tube 103 is provided at the proximal end 100a of embolic device 100. Proximal tube 103 serves to hold and secure / seal the free ends of the braided mesh structure of proximal lobe 101a that is formed during braiding. Thus, proximal tube 103 and distal tube 103 are useful in preventing the free ends of the braided mesh structure from unraveling at either end of body 101, thereby maintaining the shape of body 101.

[0061] The proximal tube 103 can be made of a radiopaque material, such as stainless steel (SS316L grade), nitinol, platinum, platinum-iridium, or tantalum. In one embodiment, the proximal tube 103 is made of SS316L. The proximal tube 103 also serves as a surgical marker to identify the location of the device 100 during fluoroscopy. The proximal tube 103 has a predefined shape and dimensions. The cross-sectional shape of the proximal tube 103 can be circular, polygonal, or the like. In one embodiment, the proximal tube 103 has a cylindrical shape with a circular cross-section. The dimensions of the proximal tube 103 can depend on the number of wires and the dimensions of each wire used in the device 100.

[0062] The distal tube may be structurally (including shape and size) and functionally identical to the proximal tube 103, and thus serves to hold and secure / seal the free ends of the braided mesh structure of the distal lobe 101b formed during braiding. Like the proximal tube 103, the distal tube may also be made of a radiopaque material such as stainless steel, nitinol, platinum, platinum-iridium, or tantalum. In one embodiment, the distal tube is made of SS316L. The distal tube (not visible) is covered by a jacket 105. The proximal tube 103 and distal tube may have an inner diameter of 0.8 mm to 1.2 mm and an outer diameter of 1.0 mm to 1.5 mm, and may further have a length of 0.8 mm to 1 mm. The jacket 105 is provided with the distal tube to serve to attach a delivery wire "w" to the device 100 for delivery and deployment procedures.

[0063] The jacket 105 can take the form of a cap that is welded or crimped over the distal tube, however, other constructional embodiments of the jacket 105 are also within the scope of the present invention.

[0064] FIG. 2b shows an exemplary configuration of jacket 105. Jacket 105 includes a uniform outer surface 105a and a recessed inner surface 105b. The recessed inner surface 105b of jacket 105 defines a first cavity 5b1 and a second cavity 5b2. First cavity 5b1 is configured to fit over the distal tube. Second cavity 5b2 is used to engage a delivery wire "w" via a delivery wire screw (202 shown in FIGS. 3 and 3b). In one embodiment shown in FIG. 2b, second cavity 5b2 includes a threaded wall for engaging delivery wire screw 202 (described in more detail below).

[0065] Thus, the dimensions of the first cavity 5b1 may depend on the dimensions of the distal tube, and the dimensions of the second cavity 5b2 may depend on the dimensions of the delivery wire screw 202.

[0066] The embolic device 100 described above may be delivered using a delivery catheter 200 and a delivery wire "w." The delivery catheter 200 navigates the embolic device 100 through the vasculature of the patient's body for delivery at the implantation site. The delivery catheter 200 may be operated using a remote control located outside the patient's body. However, other means of operating the delivery catheter 200 are also within the scope of the present invention.

[0067] The delivery wire "w" serves to guide the embolic device 100 and delivery catheter 200 through the vasculature to reach the implantation site. The delivery wire "w" is connected to the device 100 by a delivery wire screw 202, as shown in FIG.

[0068] The delivery wire "w" can take the form of an elongated flexible metal shaft or braided tube. The delivery wire "w" can be made of nitinol, medical grade low alloy stainless steel, or other biocompatible metals. In one embodiment, the delivery wire "w" takes the form of a nitinol wire tapered at its distal end, as shown in FIG. 3a.

[0069] The delivery wire "w" can be provided with a hydrophilic coating "Hc." This type of coating provides additional lubricity to the delivery wire "w," which helps minimize flow resistance during delivery of the device 100. In one embodiment, a hydrophilic coating (Hc) of polytetrafluoroethylene (PTFE) or Teflon® is provided over the delivery wire "w." This coating can be applied over the entire length of the delivery wire "w" or a portion thereof. For example, to maintain flexibility and facilitate handling, the tapered portion "w1" of the delivery wire "w" is not coated with any hydrophilic coating "Hc," as is evident from FIG. 3a.

[0070] The tapered portion “w 1 ” of the delivery wire “w” is configured to interface with the delivery wire screw 202 .

[0071] An exemplary structure of delivery wire screw 202 (or screw 202) is shown in FIG. 3b. As shown in FIG. 3b, screw 202 takes the form of a hollow cap 202a having an extension 202b. Hollow cap 202a can accommodate tapered portion "w1" of delivery wire "w". In one embodiment, tapered portion "w1" of delivery wire "w" is welded or crimped into hollow cap 202a of screw 202. Extension 202b is connected to second cavity 5b2 of jacket 105. In one embodiment, extension 202b is threaded to engage second cavity 5b2 via a threaded connection. Such a threaded connection allows for easy engagement and disengagement of embolic device 100 and delivery wire "w".

[0072] To deliver device 100, a delivery catheter 200 containing a delivery wire "w" connected to device 100 is advanced through the sheath to the implantation site.

[0073] Delivery catheter 200 includes a stock for repositioning embolic device 100 if it is determined that embolic device 100 is not properly positioned within the shunt. When embolic device 100 is deployed, delivery catheter 200 holds device 100 until it is properly positioned at the implantation site. Delivery wire "w" can be rotated about its axis to twist embolic device 100 off delivery wire screw 202.

[0074] Achieving proper positioning and placement of embolic device 100 results in the formation of an endocardial layer over embolic device 100, thereby inhibiting bacterial endocarditis and the development of thromboembolic disease.

[0075] The embolic device 100 described above is formed using a predefined method 400, as shown in FIG. 4. In step 401, the body 101 of the embolic device 100 is formed by filament braiding. In the filament braiding process, multiple wires are braided into a filament at a predefined angle. The wires can be made of a shape-memory material, such as Nitinol or a nickel-titanium alloy. The number of braided wires can range from 32 to 144, depending on the desired characteristics of the particular device 100. In one illustrative example, 72 Nitinol wires are braided at angles of 105 to 145 degrees. The wire diameter can range from 0.068 to 0.101 mm. In one example, the wire diameter is 35 microns to 120 microns.

[0076] Each braid includes two sets of essentially parallel helical strands, one set of strands oriented clockwise and the other set of strands oriented counterclockwise.

[0077] A typical pitch angle can range from 30 to 70 degrees from the longitudinal axis of the braided tubing (as a loose tubing before heat treatment). It should be noted that pitch and wire diameter are all variables that can be altered to change the shape and properties of the embolic device 100.

[0078] Therefore, at the end of step 401, a braided nitinol tube is produced using a braiding machine, and this tube is converted into a spindle design to reduce excess pressure on the wire.

[0079] In step 403, the braided tube is annealed at 505° C. for 5 minutes to heat set it into a cylindrical shape. The annealing performed in step 403 helps to obtain the device 100 with the desired shape.

[0080] In step 405, the annealed tube is formed and shape-set. To shape-set the braided tube, a mold 300 is used. The mold 300 used in the present invention is shown in FIG. 4a. The tube is placed on the mold 300 and heated at a predefined temperature for a predefined time. The parameters for shape-setting can depend on the wire material used. For example, for a Nitinol braided tube, the parameters are a temperature of 505°C and a duration of 5 minutes.

[0081] After shape-setting heat treatment, a formed tube is obtained and removed from contact with the mold surface. The formed tube corresponds to the body 101 of the embolic device 100, having a proximal lobe 101a and a distal lobe 101b connected by a bridge 101c.

[0082] In step 407, the body 101 formed in step 405 is attached onto the proximal tube 103 and the distal tube. To avoid wire fatigue and abrasion, the diameters of the proximal tube 103 and the distal tube include some clearance. The clearance is maintained within a range of 10-30% of the diameter of the proximal tube 103 and the distal tube. The proximal tube 103 and the distal tube each have an outer diameter depending on the size of the delivery catheter 200. To avoid scratching the inner surface of the delivery catheter 200 by the embolic device 100, the inner diameter of the delivery catheter 200 is larger than the outer diameter of the proximal tube 103 and the distal tube. The body 101 is coupled to the proximal tube 103 and the distal tube in a predefined manner. In one exemplary embodiment, the proximal tube 103 and the distal tube are manually attached using forceps or equivalent. The ends of the proximal lobe 101a and distal lobe 101b may be encapsulated by parafilm or similar material.

[0083] Once the tube installation is complete, the loose ends of the proximal and distal lobes 101a, 101b are sealed using laser welding, spot welding, or crimping. The distal tube facing the distal lobe 101b is provided with a jacket 105, which is welded.

[0084] In step 409, the flexible membrane is sutured to the distal lobe 101b. The polymeric fibers within the flexible membrane may include monofilament or multifilament yarns ranging from about 50 to 300 denier. Individual filaments may range from about 0.25 to 10 denier.

[0085] In one embodiment, waxed polyester sutures are used to suture the flexible membrane. The sutures tightly hold the flexible membrane over the embolic device 100. The suture size can range from 3 / 0 to 5 / 0 USP. The flexible membrane is sutured using a 2 over 2 suture pattern.

[0086] Once the flexible membrane is sutured, the embolic device 100 is formed.

[0087] In step 411, the embolic device 100 is packaged and sterilized, followed by secondary packaging and final packaging. In one embodiment, the embolic device 100 is sterilized using ETO sterilization.

[0088] To test the efficacy of the embolic device 100, in vitro testing was performed in silicone tubing to study migration of the embolic device 100, as detailed above. A 14 x 14 mm embolic device 100 was placed in 10 mm silicone tubing. Using a peristaltic pump, water was allowed to pass through the silicone tubing for 5 minutes at a flow rate of 79 ml / min. No migration of the embolic device 100 was observed at the 79 ml / min flow rate. The flow rate was gradually increased up to a maximum of 120 ml / min. Still, no migration of the embolic device 100 was observed. The embolic device 100 was also observed to completely block the flow of water through the embolic device at all test flow rates.

[0089] The scope of the present invention is limited only by the appended claims. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are exemplary, and that the actual parameters, dimensions, materials, and / or configurations will depend on the particular application or applications in which the teachings of the present invention are used.

Claims

1. An embolization device (100), comprising: a proximal lobe (101a) disposed at the proximal end (100a) of the embolic device (100), the proximal lobe (101a) having a braided mesh structure extending from a first proximal end (a1) to a first distal end (a2), the proximal lobe (101a) having a gradually decreasing diameter from the first distal end (a2) to the first proximal end (a1), the braided mesh structure being made of a plurality of braided wires forming narrow pores of variable size to completely block the blood supply at the implantation site; a distal lobe (101b) disposed at a distal end (100b) of the embolic device (100), the distal lobe (101b) having a braided mesh structure extending from a second proximal end (b1) to a second distal end (b2); a bridge (101c) connecting the proximal lobe (101a) and the distal lobe (101b), the bridge (101c) extending from the first distal end (a2) of the proximal lobe (101a) to the second proximal end (b1) of the distal lobe (101b); Equipped with An embolic device (100), wherein the distal lobe (101b) has a larger surface area than the proximal lobe (101a).

2. The embolic device (100) of claim 1, wherein the proximal lobe (101a) is conical.

3. 2. The embolic device (100) of claim 1, wherein the narrow pores of the proximal lobe (101a) have a gradually decreasing pore size ranging from 1 to 200 microns from the first distal end (a2) to the first proximal end (a1).

4. The embolic device (100) of claim 1, wherein the first proximal end (a1) of the proximal lobe (101a) is connected to a proximal tube (103) for holding and securing the free end of the braided mesh structure.

5. The embolic device (100) of claim 1, wherein the distal lobe (101b) is cylindrical.

6. The embolic device (100) of claim 1, wherein the second distal end (b2) of the distal lobe (101b) includes a concave configuration having a depth in the range of 0.1 to 2 mm.

7. The embolic device (100) of claim 1, wherein the second distal end (b2) of the distal lobe (101b) is coupled to a distal tube for holding and anchoring a free end of the braided mesh structure.

8. The embolic device (100) of claim 7, wherein the distal tube is covered with a jacket (105) to facilitate attachment of a delivery wire (w) to the embolic device (100) for delivery and deployment of the embolic device (100).

9. 10. The embolic device of claim 1, wherein the distal lobe includes a flexible membrane that facilitates endothelialization and complete embolization of blood flow within the distal lobe.

10. 10. The embolic device (100) of claim 9, wherein the flexible membrane is made of a material selected from polyethylene terephthalate (PET), expanded polytetrafluoroethylene (ePTFE), polyurethane, metallic materials, extracellular matrix, or synthetic bioabsorbable polymers.

11. 10. The embolic device (100) of claim 1, wherein the proximal lobe (101a) and the distal lobe (101b) are provided with one or more radiopaque markers made of stainless steel, nitinol, platinum, platinum-iridium, or tantalum.

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