Embolic protection device

Abstract

The disclosed embolic protection device is designed for intravascular procedures. The device includes a braided structure that makes contact with the vessel wall at both ends. The braided structure expands in diameter when compressed in length, providing additional force on the vessel wall to prevent migration of the device. The device also includes a telescoping tether with two attachment points to the braided structure. The tether controls the geometry of the braided structure, helping to resist migration of the device during a procedure. The device can also include an emboli collection portion that employs the braided structure, where the filter basket and two anti-migration ends are made from a single component. The braided structure and telescoping tether work in concert to resist migration of the device in both distal and proximal directions.

Description

Technical Field

[0001] This disclosure generally relates to medical devices for endovascular surgery, and more specifically, to embolism protection devices having anti-migration features designed to resist movement from an initial deployment location. Background Technology

[0002] Endovascular surgeries, such as angioplasty, stent placement, and thrombectomy, typically involve inserting devices inside a blood vessel. While these procedures are beneficial, they carry the risk of creating emboli—small particles or blood clots that can move in the bloodstream. If these emboli are allowed to travel downstream, they can block blood vessels, leading to serious health conditions such as heart attacks, strokes, or pulmonary embolisms. The severity of these conditions depends on the blood vessel in which the embolus originates and where it subsequently reaches.

[0003] To reduce the risk of embolism, embolic protection devices are commonly used. These devices typically consist of a filter placed inside the blood vessel to capture any emboli that may form during the procedure. The filter is designed to allow blood to flow while capturing the emboli, preventing them from moving downstream.

[0004] However, a challenge with using embolization protection devices is that they may migrate from their initial deployment location during endovascular procedures. This migration is typically attributed to movement of the traction cable attached to the filter and used for deployment and retrieval. Inadvertently pushing or pulling the traction cable while maneuvering other devices across it can unintentionally displace the filter.

[0005] Unintended migration of the filter can lead to a variety of complications, including potential damage to nearby blood vessels or organs, or migration to a location where it can no longer effectively prevent emboli from migrating downstream. To address this issue, improvements have been incorporated into currently commercially available embolism protection devices, typically designed to increase the radial force of the filter basket. This enhancement applies greater outward pressure to the vessel wall, thereby increasing friction and resistance against migration. However, this approach has its drawbacks, as the increased radial force often makes the device more difficult to track, deploy, and retrieve. Summary of the Invention

[0006] According to one aspect of the invention, an embolism protection device is provided, comprising a filter basket and a telescopic traction cable. The filter basket is configured to establish contact with a blood vessel wall at its proximal portion, wherein the diameter of the proximal portion of the filter basket expands when compressed in length. The telescopic traction cable is attached to the proximal portion of the filter basket and configured to control the geometry of the proximal portion of the filter basket.

[0007] The proximal portion of the filter basket can be configured to naturally expand in diameter when compressed in length by the telescopic traction cable.

[0008] The telescopic traction cable may include an inner layer and an outer layer, each connected to the proximal portion of the filter basket, wherein the inner and outer layers are movable relative to each other to control the length of the proximal portion of the filter basket. The inner and outer layers of the traction cable may extend along a hollow guide rail extending through the central axis of the filter basket. The telescopic traction cable may be configured to lock in an extended or retracted position, wherein the diameter of the proximal portion of the filter basket is larger in the retracted position than in the extended position.

[0009] The filter basket may also include an embolus collection portion having a first end in fluid communication with the proximal portion and a sealed second end, and a distal portion connected to the second end of the embolus collection portion, the distal portion having an expanded diameter configured to establish contact with the vessel wall. The distal portion may be configured to naturally expand in diameter when the embolism protection device migrates while in contact with the vessel wall, resulting in compression along its length.

[0010] The filter basket can be made of woven material.

[0011] The filter basket can be made of sheet fabric with pores formed therein.

[0012] The filter basket may be made of metal, fabric, or polymer, or a combination of two or more of these.

[0013] The traction cable can be attached to the proximal portion of the filter basket via a connecting element, and both the connecting element and the filter basket can be compressible for deployment via a conduit. The filter basket can be made of a shape memory material such as nitinol.

[0014] According to another aspect of the invention, an embolism protection device is provided, comprising a hollow guide rail and a traction cable, wherein the traction cable includes an inner layer extending along the hollow guide rail and an outer layer extending on the inner layer. The device also includes a filter basket comprising a cylindrical portion having an opening at a proximal end of the woven filter basket, and an embolus collection portion in fluid communication with the cylindrical portion. The device further includes a first connecting element connecting the outer traction cable to a first portion of the cylindrical portion of the filter basket, and a second connecting element connecting the inner traction cable to a second portion of the cylindrical portion of the filter basket. The first portion of the cylindrical portion is located upstream of the second portion of the cylindrical portion relative to the direction of blood flow through the embolism protection device.

[0015] The distal end of the embolus collection section can be sealed to the hollow guide rail, and the filter basket may also include a tapered end extending downstream of the distal end of the embolus collection section. The tapered end may be configured to naturally expand in diameter when the embolism protection device migrates and is compressed in length while in contact with the vessel wall.

[0016] The diameter of the plug collection section can be smaller than the diameter of the cylindrical section.

[0017] The first and second connecting elements, as well as the filter basket, can be compressible for deployment via a conduit. The filter basket can be made of a shape memory material such as nitinol. Attached Figure Description

[0018] The above and other aspects and features of the present invention will become apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: Figure 1 These are images of an embolism protection device according to an embodiment of the present invention; Figure 2 This is an embodiment of the concept of the present invention. Figure 1 Image of the device in a partially deployed state; Figure 3 This is an embodiment of the concept of the present invention. Figure 1 An image of the device in an expanded state; and Figure 4 This is an embodiment of the concept of the present invention. Figure 1 Images of the device are used to describe the remote anti-migration characteristics. Detailed Implementation

[0019] In the following detailed description, representative embodiments with specific details disclosed are set forth for purposes of explanation and not limitation, in order to provide a thorough understanding of the teachings. However, it will be apparent to those skilled in the art who benefit from this disclosure that other embodiments, departing from the specific details disclosed herein, remain within the scope of the appended claims. Furthermore, descriptions of well-known apparatuses and methods may have been omitted to avoid obscuring the description of the exemplary embodiments. These methods and apparatuses are clearly within the scope of the teachings. Additionally, throughout the drawings, the same reference numerals refer to the same or similar elements.

[0020] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. The defined terminology complements the technical and scientific meaning of the defined terminology as commonly understood and accepted in the art as taught herein. As used in the specification and appended claims, the terms “a,” “an,” and “the” include both singular and plural referents unless the context clearly indicates otherwise. Thus, for example, “an apparatus” includes one apparatus and multiple apparatuses. Furthermore, for example, when an element is described as being “connected to” another element, that one element may be directly connected to the other element or indirectly connected to the other element in an operative manner.

[0021] This disclosure relates to medical devices for endovascular procedures, and more specifically to embolism protection devices. These devices are designed to capture emboli, or small particles or blood clots that can move in the bloodstream, during endovascular procedures. The captured emboli are prevented from moving downstream to avoid potential vascular obstruction and serious health conditions.

[0022] The design and geometry of the filter play a crucial role in its performance. The device typically includes a collection basket in which emboli are captured. This basket is designed to conform to the vessel wall to ensure no emboli can bypass the device. The basket can be made of a variety of materials, including metals, fabrics, or polymers, and can be constructed in woven or mesh patterns. Some filters may also contain shape memory materials, such as nitinol, which can return to their original shape after being compressed for delivery into the blood vessel.

[0023] In embodiments of the inventive concept, the embolism protection device includes a proximal anti-migration feature. This feature may include a telescopic traction cable having attachment points connected to a filter basket. In the embodiments described herein, the filter basket is assumed to be a woven filter basket, but the inventive concept is not limited to this. For example, the filter basket may be formed as a mesh structure, or made of fabric or other materials having pores formed therein.

[0024] The traction cable can be designed to control the geometry of the braided filter basket, thereby helping to resist device migration during surgery. The telescopic traction cable can be locked in an extended or retracted position, allowing control over the geometry of the braided structure and thus the force applied to the vessel wall.

[0025] In some embodiments of the inventive concept, the filter basket of the embolism protection device includes a distal anti-migration feature. This can take the form of a woven cone that expands in diameter upon contact with the vessel wall, providing additional resistance to distal migration of the device.

[0026] In some embodiments of the present invention, the filter basket of the embolism protection device includes both proximal and distal anti-migration features.

[0027] These embodiments of the embolization protection device offer several potential benefits. For example, the device can provide improved anti-migration properties during endovascular procedures, potentially reducing the risk of complications associated with device migration. Furthermore, the device is easier to deploy and retrieve compared to existing devices, potentially improving the simplicity and efficiency of endovascular procedures.

[0028] Figure 1 This is an image of an embolism protection device according to an embodiment of the present invention.

[0029] refer to Figure 1For example, the main components of the embolism protection device shown include telescopic traction cables (1, 2, 3, 4), woven filter baskets (5, 6, 7, 8), and hollow guide rails (9).

[0030] The hollow guide rail 9 supports the remaining components of the device and allows the device to be delivered along the guidewire for positioning and removal from the target blood vessel. Using tools known in the art, the guide rail 9 can be delivered along the guidewire within the catheter to ensure precise placement and retrieval of the device. As those skilled in the art will understand, the filter basket described below is compressed during delivery within the catheter and then expands upon deployment and release from the catheter. Figure 1 The state shown. In some respects, the dimensions of the hollow guide rail 9 allow other interventional devices to be guided around (above the guidewire), beside (monorail), or inside it.

[0031] exist Figure 1 In the example, the woven filter basket includes a cylindrical portion 5, an embolus collection portion 6 with a closed end 7, and a distal tapered portion 8. When deployed, the blood flow direction is from left to right in the figure. As shown, the cylindrical portion 5 of the example tapers towards the central axis to the embolus collection portion 6. This allows blood flow through the tapering portion when blood flow through the embolus collection portion is obstructed by an embolus collected therein. However, the inventive concept is not limited to this manner. For example, the outer wall of the embolus collection portion 6 may be... Figure 1 The outer walls of the cylindrical portion 5 shown are aligned. In any case, the plug collecting portion 6 includes a closed end 7 to prevent the collected plugs from escaping. This is achieved via a hub connected to the hollow guide rail 9. As shown, the distal tapered end 8 expands outward from the sealed end 7 of the plug collecting portion. From there, the hollow guide rail 9 can continue to extend a certain distance.

[0032] It should be understood that the proximal end of the cylindrical portion 5 is open to allow blood flow and emboli (if any) to flow into the filter basket. On the other hand, at least the tapered portion of the cylindrical portion 5 and the emboli collection portion 6 are permeable to blood but impermeable to emboli. As those skilled in the art will understand, this is achieved by appropriately determining the size of the pores in the filter basket material.

[0033] At least a portion of the cylindrical section 5 is configured to form a seal against the vessel wall, preventing emboli from bypassing the filter basket. The expansion diameter of the cylindrical section 5 is larger than the diameter of the vessel, thereby exerting an outward force on the vessel wall and holding the device in place within the vessel. This portion of the cylindrical section 5 is not restricted in its permeability to blood and emboli because it is pressed against the vessel wall.

[0034] Still referencing Figure 1The telescopic traction cable includes an outer layer 1, an inner layer 2, a connecting element 3 connected to the outer layer 1, and a connecting element 4 connected to the inner layer 2. The inner layer 2 is fitted over a hollow guide rail 9, and the outer layer 1 is fitted over the inner layer 2. The inner and outer layers can move relative to each other along the length of the hollow guide rail 9. Therefore, the connecting element 3 can reciprocate along the length of the hollow guide rail 9, and so can the connecting element 4.

[0035] like Figure 1 As shown, connecting element 3 is connected to the outer proximal portion of the cylindrical portion 5 of the filter basket. In other words, connecting element 3 extends between the outer layer 1 of the telescopic traction cable and the outer proximal portion of the cylindrical portion 5. Furthermore, connecting element 4 is connected to the outer distal portion of the cylindrical portion 5 of the filter basket. In other words, connecting element 4 extends between the inner layer 2 of the telescopic traction cable and the outer distal portion of the cylindrical portion 5. Connecting elements 3 and 4 can be compressed together with the filter basket for deployment via a conduit or similar device. When released from the conduit, the collecting element expands through its connection to the naturally expanding cylindrical portion of the filter basket. Figure 1 The state shown.

[0036] Figure 1 The distal tapered portion 8 of the filter basket is also shown. As will be described later, this portion of the filter basket serves as a distal anti-migration feature of the embolism protection device.

[0037] Figure 2 This is an embodiment of the concept of the present invention. Figure 1 Image of the device in partial deployment state 11. Here, the inner layer of the traction cable extends relative to the outer layer of the traction cable.

[0038] refer to Figure 2 The external and internal telescopic connections move away from each other (as indicated by arrow 10) to elongate the cylindrical portion of the woven filter basket, which in turn reduces the diameter of the cylindrical portion, as shown by reference numeral 11 in the attached figure. The narrowed diameter facilitates the deployment and retrieval of the device.

[0039] In some cases, such as Figure 2 As illustrated in the example, the distal anti-migration feature (i.e., the distal tapered portion) maintains its shape to properly contact the vessel wall. This feature can be designed to resist device migration during surgery by maintaining a constant force on the vessel wall. This will be discussed in conjunction with the following. Figure 4 discuss.

[0040] Figure 3 This is an embodiment of the concept of the present invention. Figure 1 An image of the device in its expanded state. Here, the inner layer of the traction cable is retracted relative to the outer layer.

[0041] The cylindrical portion of the woven filter basket naturally expands in diameter when compressed in length. In embodiments of the inventive concept, this natural diameter expansion is utilized to provide additional force against the vessel wall to prevent device migration during endovascular procedures. The telescopic traction cable, comprising inner and outer layers, can be manipulated by the user to bring the proximal and distal connecting elements closer together, such as... Figure 3 As shown by arrow 13, thus achieving the following Figure 3 The diameter dilation shown in Figure 14 increases the force applied to the vessel wall, thereby inhibiting the migration of the embolic protection device within the vessel. In this way, proximal anti-migration characteristics are achieved.

[0042] When removing an embolic protection device from a blood vessel, a telescopic traction cable can be used to release the pressure of the cylindrical portion on the vessel wall. (As mentioned earlier...) Figure 2 As shown, this is achieved by extending the inner layer of the traction cable outward relative to the outer layer of the traction cable.

[0043] In some embodiments, the telescopic traction cable is configured to lock in an extended or retracted position. When locked in the extended position (e.g., as...) Figure 2 As shown), the diameter of the cylindrical portion of the filter basket is smaller than the diameter of the blood vessel wall. When locked in the retracted position (e.g., Figure 3 The diameter of the cylindrical portion of the filter basket is larger than the diameter of the blood vessel wall.

[0044] Figure 4 This is an embodiment of the concept of the present invention. Figure 1 Images of the device are used to describe the remote anti-migration characteristics.

[0045] refer to Figure 4 On the right side, the distal tapered portion of the woven filter basket is longitudinally compressed through interaction with the vessel wall. In other words, this distal portion can be configured to naturally expand in diameter when the embolization protection device migrates upon contact with the vessel wall, resulting in compression along its length. This is indicated by reference numeral 16 in the figure. The resulting increase in force applied to the vessel wall inhibits downstream migration of the embolization protection device. That is, expansion can occur when the structure at the distal end of the device forms a cone that expands in diameter upon contact with the vessel wall.

[0046] It should be understood that the size of the embolization protection device will depend on the diameter of the target blood vessel to which it is intended to be used. Nevertheless, to provide some dimensional background, some example dimensions of the device components are provided below. It is emphasized here that the inventive concept is not limited to these specific examples, nor is it limited to components having the relative dimensions shown in the examples.

[0047] For example, in the case of intravenous use, where the vein is relatively large, the cylindrical portion 5 can expand to a diameter of 33 mm when not manipulated by the telescopic traction cable. The diameter of the embolus collecting portion 6 can be 12 to 16 mm, and the distal tapered portion can expand to a diameter of 30 mm. In this case, the unmanipulated lengths of the cylindrical portion 5 and the distal tapered portion can each be 40 mm, and the length of the embolus collecting portion 6 can be 100 mm. The length of the hollow guide rail 9 can be approximately 200 cm.

[0048] In some embodiments, the device may include radiopaque filling marks on the embolus collection portion 6 of the filter basket, visible on X-ray imaging. These marks alert the physician when an embolus load approaches the taper of the inflow portion of the embolus collection portion 6, indicating that the filter may need to be emptied before proceeding with the procedure. In the case where the cylindrical portion 5 tapers as described above, this feature helps ensure that the filter does not fill beyond the area around which blood flow can bypass the filter collection portion, which would impede the design's ability to maintain blood flow.

[0049] In some embodiments, the cylindrical portion 5, the plug collecting portion 6, and the distal tapered portion 8 are formed from a single continuous material or sheet of material. However, it should be understood that two or more of these portions may be formed from separate materials and then attached together.

[0050] Although the invention has been illustrated and described in detail in the accompanying drawings and foregoing description, such illustrations and descriptions should be considered illustrative or exemplary rather than restrictive; the invention is not limited to the disclosed embodiments. Other variations of the disclosed embodiments can be understood and implemented by those skilled in the art in practicing the claimed invention by studying the drawings, the disclosure, and the appended claims. While representative embodiments have been disclosed herein, those skilled in the art will understand that many variations are possible in accordance with these teachings and remain within the scope of the appended claims. Therefore, the invention is not limited except within the scope of the appended claims.

Claims

1. An embolism protection device, comprising: A filter basket configured to establish contact with a blood vessel wall at its proximal portion, wherein the proximal portion of the filter basket expands in diameter when compressed in length; and A telescopic traction cable is attached to the proximal portion of the filter basket, wherein the telescopic traction cable is configured to control the geometry of the proximal portion of the filter basket.

2. The embolism protection device according to claim 1, wherein, The proximal portion of the filter basket is configured to naturally expand in diameter when compressed in length by the telescopic traction cable.

3. The embolism protection device according to claim 1, wherein, The telescopic traction cable includes an inner layer and an outer layer, each connected to the proximal portion of the filter basket, the inner and outer layers being movable relative to each other to control the length of the proximal portion of the filter basket.

4. The embolism protection device according to claim 3, wherein, The inner and outer layers of the traction cable extend along a hollow guide rail, which extends through the central axis of the filter basket.

5. The embolism protection device according to claim 3, wherein, The telescopic traction cable is configured to be locked in an extended or retracted position, wherein the diameter of the proximal portion of the filter basket is larger in the retracted position than in the extended position.

6. The embolism protection device according to claim 1, wherein, The filter basket also includes: An embolus collection portion having a first end in fluid communication with the proximal portion and a sealed second end; and The distal portion is connected to the second end of the embolus collection portion, the distal portion having an expansion diameter configured to establish contact with the vessel wall.

7. The embolism protection device according to claim 6, wherein, The distal portion is configured to naturally expand in diameter when the embolization protection device migrates while in contact with the vessel wall, resulting in compression in length.

8. The embolism protection device according to claim 1, wherein, The filter basket is made of woven material.

9. The embolism protection device according to claim 1, wherein, The filter basket is made of a sheet-like fabric with pores formed therein.

10. The embolism protection device according to claim 1, wherein, The filter basket is made of metal, fabric, or polymer, or a combination of two or more of these materials.

11. The embolism protection device according to claim 1, wherein, The traction cable is attached to the proximal portion of the filter basket via a connecting element, and The connecting element and the filter basket are compressible for deployment via conduits.

12. The embolism protection device according to claim 11, wherein, The filter basket is made of shape memory material.

13. The embolism protection device according to claim 12, wherein, The shape memory material is nickel-titanium.

14. An embolism protection device, comprising: Hollow guide rail; A traction cable, the traction cable comprising an inner layer extending along the hollow guide rail and an outer layer extending on the inner layer; A filter basket comprising a cylindrical portion and a plug collection portion, the cylindrical portion having an opening at a proximal end of the woven filter basket, the plug collection portion being in fluid communication with the cylindrical portion; A first connecting element connecting the outer traction cable to a first portion of the cylindrical section of the filter basket; as well as A second connecting element connecting the inner traction cable to the second portion of the cylindrical section of the filter basket. Wherein, relative to the blood flow direction through the embolism protection device, the first portion of the cylindrical section is located upstream of the second portion of the cylindrical section.

15. The embolism protection device according to claim 14, wherein, The distal end of the plug collection section is sealed to the hollow guide rail, and the filter basket also includes a tapered end extending downstream of the distal end of the plug collection section.

16. The embolism protection device according to claim 6, wherein, The tapered end is configured to naturally expand in diameter when the embolization protection device migrates while in contact with the vessel wall, resulting in compression in length.

17. The embolism protection device according to claim 14, wherein, The diameter of the plug collecting section is smaller than the diameter of the cylindrical section.

18. The embolism protection device according to claim 14, wherein, The first connecting element, the second connecting element, and the filter basket are compressible for deployment via conduits.

19. The embolism protection device according to claim 18, wherein, The filter basket is made of shape memory material.

20. The embolism protection device according to claim 19, wherein, The shape memory material is nickel-titanium.

Images