Small vasculature clot extrusion

Abstract

A clot removal assembly for removing a clot from a blood vessel is presented. The clot removal assembly includes a delivery catheter, a clot retrieval device, and a valve assembly. In some examples, a clot retrieval device may include a cage structure and a shaft, and the cage structure may be configured to grip a clot. A portion of the shaft extends through the delivery catheter. In some examples, the valve assembly may include a distal valve, a main body portion, a distal body portion, and a movable head housing. The distal valve may be configured to engage a proximal region of the delivery catheter. In some examples, the distal body portion may include a plurality of grooves, and the movable head may be configured to ratchet proximally over the plurality of grooves to maintain tension on the shaft.

Description

Technical Field

[0001] The present disclosure generally relates to devices and methods for removing occlusions from blood vessels during endovascular medical treatment. Background Art

[0002] In cases where a patient has a condition such as acute ischemic stroke (AIS), myocardial infarction (MI), and pulmonary embolism (PE), clot retrieval devices are often used in mechanical thrombectomy for endovascular intervention.

[0003] Tough fibrin-rich clots can be located in distal blood vessels that are smaller compared to proximal blood vessels. These types of clots generally cannot be retrieved by aspiration alone, and currently available clot retrieval devices are either too large and can damage the blood vessel wall or too small to effectively grasp tough distal clots. Due to the difficulty of bonding the shaft to the clot retrieval cage structure, a properly sized clot retrieval device for these tough distal clots has not been achieved to date. The applicant has recognized a need to bond a properly sized clot retrieval cage structure for removing these tough distal clots to a shaft that allows use with a properly sized catheter for delivering the cage structure to the distal blood vessel.

[0004] Clots can have any of a range of morphologies and consistencies. For example, clots may be difficult to grip, and improper gripping can cause fragmentation, which can lead to embolism. Compression of a blood clot causes dehydration of the clot and results in a significant increase in both the hardness and coefficient of friction of the clot, which requires removal by clamping rather than contact aspiration.

[0005] Physicians typically rely on visual and tactile feedback to evaluate the engagement of a clot with a clot retrieval device. In some treatments, it may be difficult to determine whether a clot is engaged by a clot retrieval device of the present technology. It may also be difficult to maintain an appropriate tension between the clot retrieval device and a proximal component, but this tension is necessary for maintaining engagement with the clot. Devices, systems, and methods are disclosed herein. Summary of the Invention

[0006] In some examples, a clot removal device for removing a clot from a blood vessel is disclosed. The clot removal device can include: a cage structure including a first tapered portion at a proximal end of the cage structure; a shaft including a second tapered portion at a distal end of the shaft; and a proximal junction, wherein the first tapered portion is positioned in a non-engaging overlap with the second tapered portion. The proximal junction can include a weld between the first tapered portion and the second tapered portion and a material coating over at least a portion of the first tapered portion, at least a portion of the second tapered portion, and at least a portion of the weld.

[0007] In some examples, the non-engaging overlap portion can be laser welded at two points, and the material coating can be bonded to the shaft and cage structure at two points.

[0008] In some examples, the distal shaft portion can be conical, narrower distally and wider proximally.

[0009] In some examples, the cage structure can further include an open distal end and a proximal helical segment. The proximal helical segment can include a first plurality of struts that extend distally from the proximal end of the cage structure and are configured to clamp a clot between at least one of the first plurality of struts. The proximal helical segment can extend from the proximal end to the open distal end over most of the length of the cage structure.

[0010] In some examples, the cage structure can further include a cylindrical body segment located distally of the proximal helical segment. The cylindrical body segment can include a second plurality of struts greater than the first plurality of struts, and the cylindrical body segment has a length that is measured to be less than the length of the proximal helical segment. In some examples, the cylindrical body segment has an outer diameter of approximately 2.5 mm.

[0011] In some examples, a clot removal assembly for removing a clot from a blood vessel is disclosed. The clot removal assembly can include a delivery catheter, a clot retrieval device, and a valve assembly. In some examples, the delivery catheter can include a distal region and a proximal region. In some examples, the clot retrieval device can include a cage structure and a shaft, and the cage structure can be configured to clamp a clot. A portion of the shaft extends through the delivery catheter. In some examples, the valve assembly can include a distal valve, a main body portion, a distal body portion, and a movable head housing. The distal valve can be configured to engage the proximal region of the delivery catheter. In some examples, a portion of the shaft extends through the lumen of the main body portion. In some examples, the distal body portion can include a plurality of grooves, and the movable head can be configured to ratchet proximally over the plurality of grooves to maintain tension on the shaft.

[0012] In some examples, the movable head housing can include teeth configured to engage the grooves, a threaded portion, and a threaded head configured to engage the threaded portion and compress a seal. The seal locks the shaft in place relative to the threaded head when compressed, and the teeth are configured to disengage from the grooves of the main body when flexed away from the central axis of the valve.

[0013] In some examples, the cage structure can include a proximal helical segment and a cylindrical body segment located distally of the proximal helical segment. The cylindrical body segment can include a second plurality of struts greater than the first plurality of struts of the proximal helical segment. In some examples, the cylindrical body segment can include a length that is measured to be less than the length of the proximal helical segment.

[0014] In some examples, the clot removal assembly may further include a proximal junction that connects the shaft to the proximal helical segment. The proximal junction is formed by laser welding a non-engaging overlap between a tapered portion of the shaft and a tapered portion of the cage structure together and applying a material coating over the proximal junction. In some examples, the non-engaging overlap is laser welded at two points, and the material coating is bonded to the shaft and cage structure at two points.

[0015] In some examples, the movable head housing may further include an outer gripper disposed on the proximal end of the movable head housing.

[0016] In some examples, the distal end of the movable head housing may include a thin plastic cylindrical wall configured to deform in response to clamping, and the clamping causes deflection away from the central axis of the valve.

[0017] In some examples, the catheter may further include an inner diameter of approximately 0.013 inches.

[0018] In some examples, a method of removing a clot from a blood vessel is disclosed. The method may include: deploying at least a portion of the cage structure of the clot retrieval device outside the catheter and across the clot; engaging the proximal portion of the catheter to the distal valve of the valve assembly; engaging the proximal portion of the shaft of the clot retrieval device to the movable head housing of the valve assembly; pulling the movable head housing of the valve in the proximal direction to clamp the clot; fixing the movable head housing relative to the distal valve to maintain tension on the shaft, and extracting the cage structure and the clot from the blood vessel.

[0019] In some examples, fixing the movable head housing relative to the distal valve to maintain tension on the shaft may include: engaging teeth disposed on the movable head housing with a first groove disposed on the distal body portion of the valve assembly, and gripping the shaft by compressing a seal between a threaded head and a threaded portion of the movable head housing.

[0020] In some examples, fixing the movable head housing relative to the distal valve to maintain tension on the shaft may include: sliding the movable head housing proximally and engaging the teeth with a second groove closer to the proximal direction compared to the first groove.

[0021] In some examples, the method may include applying suction to the catheter through a side port disposed on the valve.

[0022] In some examples, the method may include releasing the tension by clamping the movable head housing to disengage the teeth.

[0023] In some examples, the method may further include moving the cage structure to pin the clot between the cage structure and the inner wall of the blood vessel.

[0024] In some examples, the clot may be composed mostly of fibrin.

[0025] In some examples, the method may include extracting the clot from the distal M2, M3, M4, A2 - 5, or P2 - P5 blood vessels.

[0026] After reviewing the following detailed description in conjunction with the accompanying drawings, other aspects and features of the present disclosure will become apparent to those skilled in the relevant art. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The foregoing and other aspects of the present disclosure will be further discussed with reference to the following description of the drawings, in which like numerals indicate identical structural elements and features in each of the various figures. The drawings are not necessarily to scale, but rather emphasis is placed on illustrating the principles of the present disclosure. The drawings depict one or more specific embodiments of the inventive apparatus by way of example and not by way of limitation. It is expected that those skilled in the art will be able to conceive and combine elements from multiple drawings to better meet the needs of the user.

[0028] Figure 1 A perspective view of a clot removal assembly having a delivery catheter, a clot retrieval device, and a valve assembly in accordance with the present disclosure is shown.

[0029] Figure 2 is Figure 1 an isometric view of the clot retrieval catheter shown.

[0030] Figure 3 A cross - sectional view of a junction in accordance with the present disclosure is shown.

[0031] Figure 4 is an isometric view and an enlarged cross - sectional view of a micro - catheter in accordance with the present disclosure.

[0032] Figure 5A is a cross - sectional view of a blood vessel and a clot and a clot removal assembly disposed therein in accordance with the present disclosure.

[0033] Figure 5B is a cross - sectional view of a blood vessel and a clot and a clot removal assembly engaged to the clot in accordance with the present disclosure.

[0034] Figure 6 A valve assembly in accordance with the present disclosure is shown.

[0035] Figure 7 A portion of a valve assembly including a movable head housing having an external clamp in accordance with the present disclosure is shown.

[0036] Figure 8A flowchart showing a method for removing a clot from a blood vessel in accordance with aspects of the present disclosure. Detailed Description

[0037] The following detailed description is merely exemplary in nature and is not intended to limit the present disclosure or the application and uses of the present disclosure. Although the description of the present disclosure is in the context of treating intracranial arteries in many cases, the present disclosure can also be used in other body channels as described above.

[0038] The terms "distal" or "proximal" are used below in the description of position or direction relative to the treating physician. "Distal" or "distally" is the position away from the physician or in the direction away from the physician. "Proximal" or "proximally" or "proximal" is the position near the physician or in the direction towards the physician.

[0039] As discussed herein, a "patient" or "individual" can be a human or any animal. It should be understood that the animal can be of any suitable type, including but not limited to mammals, veterinary animals, livestock animals, or pet animals, etc. For example, the animal can be an experimental animal specifically selected to have certain characteristics similar to humans, such as rats, dogs, pigs, monkeys, etc.

[0040] As used herein, the term "about" or "approximately" for any numerical value or range indicates a suitable dimensional tolerance that allows a collection of parts or components to achieve its intended purpose as described herein. More specifically, "about" or "approximately" can refer to a range of values ±20% of the recited value. For example, "about 90%" can refer to a value range from 71% to 99%.

[0041] When used herein, the terms "tubular" and "tube" should be understood broadly and are not limited to structures that are a perfect cylinder or have a completely circular cross-section or have a uniform cross-section throughout their entire length. For example, a tubular structure or system is typically illustrated as a structure that is substantially cylindrical. However, without departing from the scope of the present invention, the tubular system can have a tapered or curved outer surface.

[0042] "Comprising" or "containing" or "including" means that at least the named compound, element, particle, or method step is present in the composition or article or method, but does not exclude the presence of other compounds, materials, particles, method steps, even if such other compounds, materials, particles, method steps have the same function as the named ones.

[0043] It should also be noted that, unless the context clearly dictates otherwise, the singular forms "a / an" and "the" as used in this specification and the appended claims include plural referents. Ranges may be expressed herein as "about" or "approximately" a particular value and / or "about" or "approximately" another particular value. When expressing such ranges, other exemplary examples include from a particular value and / or to another particular value.

[0044] Access to the cerebral, coronary, and pulmonary blood vessels involves the use of many commercially available products and conventional procedural steps. Access products such as guidewires, guiding catheters, angiographic catheters, and microcatheters are described elsewhere and are commonly used in catheter laboratory procedures. In the following description, it is assumed that these products and methods are used in combination with the devices and methods of the present disclosure and do not require detailed description.

[0045] A common theme among many of the disclosed designs is a clot removal assembly 200 for removing a clot 700 from a blood vessel. The clot removal assembly 200 may include a delivery catheter 300, a clot retrieval device, and a valve assembly.

[0046] Figure 1 is an illustration of an exemplary clot removal assembly for removing a clot 700 from a blood vessel. The clot removal assembly may include a delivery catheter 300, a clot retrieval device 110, and a valve assembly 400. In some examples, the clot retrieval device 100 may include a cage structure 110 and a shaft 120, and the cage structure 110 may be configured to clamp the clot 700. A portion of the shaft 120 extends through the delivery catheter 300. In some examples, the valve assembly 400 may include a distal valve 427, a main body portion 410, a distal body portion 412, and a movable head housing 420. The distal valve 427 may be configured to engage a proximal region 320 of the delivery catheter 300. In some examples, a portion of the shaft 120 extends through the lumen of the main body portion. In some examples, the distal body portion 412 may include a plurality of grooves 411, and the movable head 420 may be configured to move proximally in a ratcheting motion over the plurality of grooves 411 to maintain tension on the shaft 120. In some examples, the shaft 120 may be a tapered spool and may be made of stainless steel, MP35N, nitinol, or other materials having an appropriate high modulus and tensile strength.

[0047] Figure 2 is Figure 1 an isometric view of the clot retrieval catheter shown. In some examples, the clot removal device 100 may include a cage structure 110 that includes a first tapered portion at a proximal end 119 of the cage structure 110; a shaft 120 that includes a second tapered portion at a distal end of the shaft 120; and a proximal junction 123, wherein the first tapered portion is positioned in a non-engaging overlap 130 with the second tapered portion (see Figure 3)。

[0048] In some examples, the cage structure 110 may further include an open distal end 113 and a proximal helical segment 111. The proximal helical segment 111 may include a first plurality of struts 112 that extend distally from the proximal end 119 of the cage structure 110 and are configured to clamp a clot 700 between at least one of the first plurality of struts 112. The proximal helical segment 111 may extend from the proximal end 119 to the open distal end 113 over a majority of the length 127 of the cage structure 110.

[0049] In some examples, the cage structure 110 may further include a cylindrical body segment 114 located distally of the proximal helical segment 111. The cylindrical body segment 114 may include a second plurality of struts 115 that are greater in number than the first plurality of struts 112, and the cylindrical body segment 114 has a length 116 that is measured to be less than the length 117 of the proximal helical segment 111. In some examples, the cylindrical body segment 114 has an outer diameter 118 of approximately 2.5 mm.

[0050] The disclosed cage structure 110 of the design is desirably made of a material that is capable of automatically restoring its shape once released from a highly strained delivery configuration. Superelastic materials such as nitinol or alloys of similar nature are particularly suitable. The material may be in various forms, such as wire or strip or sheet or tube. A particularly suitable manufacturing process is to laser cut a nitinol tube and then thermally shape and electropolish the resulting structure to form a framework of struts and connecting elements. The framework may be of any of the various shapes disclosed herein and may be rendered visible under fluoroscopy by adding alloying elements or by various other coatings or marker bands.

[0051] In some examples, the cage structure 110 may further include units, struts, and various shapes and designs configured to clamp fibrin-rich clots, including those described in U.S. Patent Nos. 10,292,723; 10,363,054; 10,617,435; 11,253,278; and 11,147,572, each of which is hereby incorporated by reference in its entirety as if set forth verbatim herein. Compression of the clot 700 by the cage structure 110 (including by the cylindrical body segment 114) may alter clot properties and render the clot less retrievable by making the clot 700 firmer and "stickier", similar to that described in WO2012 / 120490A, the entire content of which is hereby incorporated by reference.

[0052] In some examples, distal advancement of the catheter 300 relative to the cage structure 110 can compress the clot 300 between the distal end of the catheter 300 and the cage structure 110, thereby increasing the clamping of the clot 700 and the security of the trapped clot segments. The user may perceive this clamping as resistance and stop advancing the catheter 300. The user may advance the delivery catheter 300 a fixed distance over the shaft 120, such as 30% to 50% of the shaft length.

[0053] Figure 3 A cross-sectional view of a junction in accordance with the present disclosure is shown. In some examples, the proximal junction 123 may include a weld between a first tapered portion and a second tapered portion and a material coating 124 over at least a portion of the first tapered portion, at least a portion of the second tapered portion, and at least a portion of the weld. In some examples, the non-junction overlap 130 may be laser welded at two points 133, and the material coating 124 may be bonded to the shaft 120 and the cage structure 110 at two points 134.

[0054] In some examples, the clot removal assembly may further include a proximal junction 123 that connects the shaft 120 to the proximal helical segment 111. The proximal junction 123 may be formed by laser welding together the non-junction overlap 130 between the tapered portion of the shaft 120 and the tapered portion of the cage structure 110 and disposing a material coating 124 on and / or over the proximal junction 123. In some examples, the non-junction overlap 130 is laser welded at two points 133, and the material coating 124 is bonded between two points 134 to the shaft 120 and the cage structure 110. Thus, in one example, once the non-junction overlap 130 is welded 133, the material coating 124 can act as a "sleeve" that further covers and strengthens the joint (i.e., the non-junction overlap 130) and is coated when necessary (i.e., between the points 134) to provide that support. Note that in some examples, the material coating 124 may be a physical polymer sleeve.

[0055] One object of the present invention is to reduce the size of the proximal junction 123, which serves as a joint between the cage structure 110 and the shaft 120. The joints of the prior art can be 0.018" at the widest point. The proximal junction 123 of the present invention allows for a size reduction to pass through a 0.013" delivery catheter. Even at its maximum size, this can be a size reduction of approximately 38% compared to the prior art. Note that the sizes of some prior art stent retrievers are designed to treat large vessel occlusions (LVO) that occur when the main artery in the brain is blocked. LVO stroke occlusions occur in one of the following major intracranial arteries in the brain: internal carotid artery (ICA), ICA terminus (T-lesion; T-occlusion). More distal clots form in smaller arteries, including in the distal M2, M3, M4, A2 - A5, P2 - P5 vessels. The smaller the proximal junction 123, the smaller the delivery catheter, and thus the cage device 110 can be delivered deeper into the cerebral blood vessels compared to most prior art devices.

[0056] In some examples, the distal shaft portion 121 can be tapered, narrower distally and wider proximally.

[0057] Figure 4 is an isometric view and an enlarged cross-sectional view of an exemplary catheter 300. In some examples, the delivery catheter 300 can include a distal region 310 and a proximal region 320. In some examples, the distal portion 310 of the delivery catheter 300 can include a coiled core, and the proximal portion 320 of the delivery catheter 300 can include a braided core.

[0058] In some examples, the coiled core can provide a level of flexibility to the catheter 300, which allows the user to better navigate tortuous distal blood vessels. In some examples, the braided core of the proximal portion 320 can provide a level of column strength to the delivery catheter 300, which helps the user to navigate the tip of the microcatheter to the target anatomy.

[0059] In some examples, the catheter 300 can be configured such that a compressive force applied to most of the length of the catheter 300 causes the proximal region 320 to remain substantially straight and the distal region to become wavy.

[0060] In some examples, the catheter 300 can be configured to deliver the clot retrieval device 100 across the clot 700.

[0061] In some examples, the catheter 300 can be configured to clamp the clot 700 between the distal end of the catheter and the clot retrieval device 100.

[0062] In some examples, the catheter 300 can also include an inner diameter of approximately 0.013 inches.

[0063] Figure 5AA cross-sectional view of blood vessel 800, clot 700, and clot removal assembly 200 disposed therein. In some examples, catheter 300 may be configured to deliver clot retrieval device 100 across clot 700.

[0064] Figure 5B is Figure 1 A cross-sectional view of blood vessel 800, clot 700, and clot removal assembly 200 shown, wherein clot removal assembly 200 is engaged to clot 300. In some embodiments, the proximal helical segment 111 of cage structure 110 may be sized to wind against the wall of blood vessel 800 within blood vessel 800. The helical segment 111 may push clot 700 into the blood vessel wall, thereby pinning clot 700 such that clot 700 is prevented from moving distally through blood vessel 800. Catheter 300 may be advanced distally such that helical segment 111 moves towards each other like tweezers.

[0065] Clot 700 may have a firm portion that can be clamped between the distal end of catheter 300 and the helical segment 111 of cage structure 110. This clamping can be achieved by advancing catheter 300 or an intermediate catheter over cage structure 110 until a portion of clot 700 is compressed between the distal end of the catheter 300 and a crown or strut on the proximal portion of the cage structure 110. This clamping facilitates the removal of clot 700 as it increases the grip of the cage structure 110 on the clot, particularly fibrin-rich clots. Proximal retraction of the clamped clot can elongate clot 700 by pulling clot 700 away from the blood vessel wall during displacement, thereby reducing the displacement force.

[0066] Figure 6 is a cross-section of valve assembly 400 according to the present disclosure. In some examples, valve assembly 400 may include a distal valve 427, a main body portion 410, a distal body portion 412, and a movable head housing 420. Distal valve 427 may be configured to engage the proximal region 310 of delivery catheter 300. In some examples, a portion of shaft 120 extends through the lumen 413 of main body portion 410. In some examples, distal body portion 412 may include a plurality of grooves 411, and movable head housing 420 may be configured to perform a ratchet movement proximally over the plurality of grooves 411 to maintain tension on shaft 120.

[0067] During certain procedures, shaft tension may be important. As described above, the cage structure 110 of the present invention is designed to clamp small, tough clots. Once the clot is clamped, any release of tension on the shaft can release the clamping and the clot. By providing control on valve assembly 400 to allow the user to maintain tension on the shaft, it helps to maintain that tension.

[0068] In some examples, the movable head housing 420 may include teeth 421 configured to engage the groove 411, a threaded portion 422, and a threaded head 424 configured to engage the threaded portion 422 and compress a seal 425, where the seal 425 locks the shaft 120 in place relative to the threaded head 424 when compressed, and where the teeth 421 are configured to disengage from the groove 411 of the main body 410 when flexed away from the central axis 430 of the valve 400.

[0069] Figure 7 A portion of a valve assembly 400 according to the present disclosure is shown, which includes a movable head housing 420 having an external clamp 426. In some examples, the movable head housing 420 may further include an external clamp 426 disposed on the proximal end 423 of the movable head housing 420. In some examples, the distal end 427 of the movable head housing 420 may include a thin plastic cylindrical wall configured to deform in response to clamping, and where the clamping causes flexure away from the central axis of the valve.

[0070] Figure 8 A method 500 of removing a clot from a blood vessel as disclosed herein is shown. As will be appreciated, Figure 8 the method steps in may be implemented by any of the example devices described herein or by similar devices.

[0071] At block 510, the method 500 may include: deploying at least a portion of a cage structure of a clot retrieval device outside of a catheter and across the clot. The cage structure of the clot removal device may be constructed similar to the example cage structure 110 of the clot removal device 100 disclosed herein, its variations, and its alternatives, as understood by those skilled in the relevant art. The structure may be deployed similar to as Figure 5A and Figure 5B shown and otherwise disclosed herein, its variations, and its alternatives, as understood by those skilled in the relevant art. The clot removal device may be configured similar to the example clot removal 100 disclosed herein, its variations, and its alternatives, as understood by those skilled in the relevant art.

[0072] At block 520, the method 500 may include: engaging a proximal portion of the catheter to a distal valve of a valve assembly. The catheter may be configured similar to the example catheter 300 disclosed herein, its variations, and its alternatives, as understood by those skilled in the relevant art. The valve assembly may be configured similar to the example valve assembly (or its sub-components) 400 disclosed herein, its variations, and its alternatives, as understood by those skilled in the relevant art.

[0073] At block 525, method 500 may include: engaging a proximal portion of the shaft of the clot retrieval device to the movable head housing of the valve assembly. The shaft may be configured similar to example shaft 120, its variations, and its alternatives disclosed herein, as would be understood by those of ordinary skill in the relevant art.

[0074] At block 530, method 500 may include: pulling the movable head housing of the valve in a proximal direction to clamp the clot.

[0075] At block 540, method 500 may include: fixing the movable head housing relative to the distal valve, thereby maintaining tension on the shaft.

[0076] At block 550, method 500 may include: extracting the cage structure and the clot from the blood vessel. In some examples, method 500 may include: extracting clot 700 from the distal M2, M3, M4, A2 - 5, or P2 - P5 blood vessels. The dimensions of any of these blood vessels are known in the art, and those of ordinary skill in the relevant art will understand that the dimensions of the components of the clot removal assembly can be appropriately set to achieve the goal of removing the clot from these blood vessels. Although such knowledge of blood vessel dimensions is known to those of ordinary skill in the relevant art, it has been very difficult to manufacture a clot removal device as disclosed herein due to the difficulty of attaching the clamping cage structure to the shaft. This problem is solved by the junctions described herein.

[0077] In some examples, method 500 may include using fluoroscopic imaging techniques.

[0078] In some examples, clot 700 may be composed mostly of fibrin.

[0079] As described in this document, a series of designs are envisioned for each of these elements, and any of these elements can be used in combination with any other element, but for the sake of avoiding repetition, they are not shown in every possible combination.

[0080] After viewing the following detailed description in conjunction with the accompanying drawings, other aspects and features of the present disclosure will become apparent to those of ordinary skill in the art.

[0081] In describing the examples, terms are used for the sake of clarity. Each term is intended to embrace the broadest meaning that would be understood by a person skilled in the art, and includes all technical equivalents that operate in a similar manner to achieve a similar purpose. It should also be understood that the mention of one or more steps of a method does not exclude the presence of additional method steps or intermediate method steps between those expressly identified. The steps of the method may be performed in an order different from that described herein without departing from the scope of the disclosed technology. Similarly, it should also be understood that the mention of one or more components in a device, system, or assembly does not exclude the presence of additional components or intermediate components between those expressly identified.

[0082] The description contained herein is an example of the present disclosure and is not intended to limit the scope of the present disclosure in any way. While specific examples of the present disclosure have been described, various modifications to the devices and methods may be made without departing from the scope and spirit of the present disclosure. For example, while the examples described herein relate to specific components, the present disclosure includes other examples that utilize various combinations of components to achieve the functions, utilize alternative materials to achieve the functions, combine the components of the individual examples, combine the components of the individual examples with known components, etc. The present disclosure contemplates replacing the components shown herein with other well-known and commercially available products. Such modifications are generally obvious to those of ordinary skill in the art to which the present disclosure pertains and are intended to fall within the scope of the following claims.

Claims

1. A clot removal device, comprising: a cage structure including a first tapered portion at a proximal end of the cage structure; a shaft including a second tapered portion at a distal end of the shaft; and a proximal coupling portion, wherein the first tapered portion is positioned in a non - engaging overlap with the second tapered portion, the proximal coupling portion including a welded portion between the first tapered portion and the second tapered portion and a material coating over at least a portion of the first tapered portion, at least a portion of the second tapered portion, and at least a portion of the welded portion.

2. The clot removal device according to claim 1, wherein, The non - engaging overlap is laser welded at two points, and wherein the material coating is bonded to the shaft and the cage structure at two points.

3. The clot removal device according to claim 1, wherein, The second tapered portion is conical, narrower distally and wider proximally.

4. The clot removal device according to claim 1, wherein, The cage structure further includes: an open distal end; and a proximal helical segment including a first plurality of struts that extend distally from the proximal end of the cage structure and are configured to clamp a clot between at least one of the first plurality of struts, the proximal helical segment extending from the proximal end to the open distal end over a majority of the length of the cage structure.

5. The clot removal device according to claim 4, wherein, The cage structure further includes a cylindrical body segment distal to the proximal helical segment, wherein the cylindrical body segment includes a second plurality of struts greater than the first plurality of struts, and wherein the cylindrical body segment includes a length that is measured to be less than the length of the proximal helical segment.

6. The clot removal device according to claim 5, wherein, The cylindrical body segment includes an outer diameter of approximately 2.5 mm.

7. A clot removal assembly, comprising: a delivery catheter including a distal region and a proximal region; a clot retrieval device including a cage structure and a shaft, wherein the cage structure is configured to clamp a clot and wherein a portion of the shaft extends through the delivery catheter; and a valve assembly including a distal valve, a main body portion, a distal body portion, and a movable head housing, wherein the distal valve is configured to engage the proximal region of the delivery catheter, wherein a portion of the shaft extends through the lumen of the main body portion, wherein the distal body portion includes a plurality of grooves, and wherein the movable head housing is configured to ratchet proximally over the plurality of grooves to maintain tension on the shaft.

8. The clot removal assembly according to claim 7, wherein, The movable head housing includes: teeth configured to engage the grooves; a threaded portion; and a threaded head configured to engage the threaded portion and compress a seal, wherein the seal, when compressed, locks the shaft in place relative to the threaded head, and wherein the teeth are configured to disengage from the grooves of the main body portion when flexed away from the central axis of the valve assembly.

9. The clot removal assembly according to claim 7, wherein, The cage structure includes a proximal helical segment and a cylindrical body segment distal to the proximal helical segment, wherein the cylindrical body segment includes a second plurality of struts greater than the first plurality of struts of the proximal helical segment.

10. The clot removal assembly according to claim 9, wherein, The cylindrical body segment includes a length, and the length of the cylindrical body segment is measured to be less than the length of the proximal helical segment.

11. The clot removal assembly according to claim 9, further comprising a proximal junction connecting the shaft to the proximal helical segment, wherein the proximal junction is formed by laser welding a non-joint overlap between a tapered portion of the shaft and a tapered portion of the cage structure and providing a material coating on the proximal junction.

12. The clot removal assembly according to claim 11, wherein, The non-joint overlap is laser welded at two points, and wherein the material coating is bonded to the shaft and the cage structure at two points.

13. The clot removal assembly according to claim 7, wherein, The movable head housing further includes an external gripper disposed on the proximal end of the movable head housing.

14. The clot removal assembly according to claim 7, wherein, The distal end of the movable head housing includes a thin plastic cylindrical wall configured to deform in response to clamping, and wherein the clamping causes the flexure.

15. The clot removal assembly according to claim 14, wherein, The delivery catheter further includes an inner diameter of approximately 0.013 inches.

16. A method of removing a clot from a blood vessel, comprising: deploying at least a portion of the cage structure of the clot retrieval device outside the catheter and across the clot; engaging a proximal portion of the catheter to a distal valve of a valve assembly; engaging a proximal portion of the shaft of the clot retrieval device to the movable head housing of the valve assembly; pulling the movable head housing of the valve in a proximal direction to clamp the clot; fixing the movable head housing relative to the distal valve to maintain tension on the shaft; and extracting the cage structure and the clot from the blood vessel.

17. The method according to claim 16, wherein, Fixing the movable head housing relative to the distal valve to maintain tension on the shaft includes: engaging teeth disposed on the movable head housing with a first groove disposed on a distal body portion of the valve assembly; and grasping the shaft by compressing a seal between a threaded head and a threaded portion of the movable head housing.

18. The method according to claim 17, wherein Fixing the movable head housing relative to the distal valve to maintain tension on the shaft includes sliding the movable head housing proximally and engaging the teeth with a second groove closer to the proximal direction than the first groove.

19. The method according to claim 18, further comprising applying suction to the catheter through a side port provided on the valve.

20. The method according to claim 18, further comprising releasing the tension by clamping the movable head housing to disengage the teeth.

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