Blood clot retrieval device for removing blood clots from blood vessels

Abstract

To provide a clot removal device.SOLUTION: A clot removal device includes a first scaffolding section, and a second scaffolding section distal to the first scaffolding section by a first hinged element including a pinching cell. The pinching cell has a collapsed state and an expanded state that is configured to pinch at least a portion of a clot. A third scaffolding section is distal to the second scaffolding section by a second hinged strut element including a pinching cell that has a collapsed state and an expanded state that is configured to pinch at least a portion of the clot. An outer diameter of the third scaffolding section is greater than an outer diameter of the second scaffolding section, which is greater than an outer diameter of the first scaffolding section.SELECTED DRAWING: Figure 1

Description

Technical Field

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

Background Art

[0002] Thrombectomy devices are often used for mechanical thrombus removal in endovascular interventions when a patient suffers from acute ischemic stroke (AIS), myocardial infarction (MI), pulmonary embolism (PE), etc. Acute occlusions can include blood clots, misplaced devices, displaced devices, large emboli, etc. Thromboembolism occurs when part or all of a thrombus detaches from the vessel wall. This blood clot (herein referred to as an embolus) is then carried in the direction of blood flow. Ischemic stroke can result when a blood clot blocks the cerebral vasculature. Pulmonary embolism can result when a blood clot forms in the venous system or on the right side of the heart and lodges in the pulmonary artery or its branches. Blood clots can also occur in the form of emboli and locally occlude blood vessels without being released, and this mechanism is common in the formation of coronary artery occlusions. There are significant challenges associated with the design of thrombectomy devices that can provide high levels of performance. First, there are many access-related issues that make it difficult to deliver the device. When access involves navigating the aortic arch (such as in coronary artery occlusion or brain occlusion), the shape of the aortic arch in some patients makes it difficult to position the guide catheter. These difficult aortic arch configurations are classified as type II or type III aortic arches, with type III aortic arches presenting the greatest obstacle.

[0003] The problem of tortuosity is even more critical in arteries approaching the brain. For example, it is not uncommon at the distal end of the internal carotid artery for a device to have to continuously progress over a few centimeters of blood vessel with vascular segments having 180° bends, 90° bends, and 360° bends. In the case of pulmonary embolism, access is through the venous system and then through the right atrium and right ventricle of the heart. The right ventricular outflow tract and pulmonary artery are delicate blood vessels that can be easily damaged by inflexible or high-profile devices. For these reasons, it is desirable for a clot retrieval device to be compatible with a guide catheter that is as low-profile and flexible as possible.

[0004] Second, the vasculature in regions where clots may be lodged is often fragile and delicate. For example, the blood vessels of the neurovascular bundle are more fragile than similarly sized blood vessels in other parts of the body and lie in a soft tissue bed. Excessive tensile forces applied to these blood vessels can result in perforation and bleeding. Pulmonary blood vessels are larger than those of the cerebrovascular system but are also inherently delicate, especially the more distal pulmonary blood vessels.

[0005] Third, clots can include any of a range of forms and consistencies. For example, a clot can be difficult to grip, and improper gripping can lead to fragmentation that can cause embolization. Long, stringy, softer clot material also tends to clog at branch or trifurcation points, such that multiple blood vessels can be occluded simultaneously over a significant length. More mature and organized clot material may be less compressible than softer, fresher clots and, under the action of blood pressure, can expand the soft blood vessels in which it is lodged. Furthermore, the inventors have discovered that the properties of a clot can be significantly changed by the action of a device that interacts with it. Specifically, compression of a clot causes dehydration of the clot, dramatically increasing both the hardness and coefficient of friction of the clot. SUMMARY OF THE INVENTION PROBLEMS TO BE SOLVED BY THE INVENTION

[0006] In order for any device to achieve a high level of success by removing blood clots and restoring flow, it is necessary to overcome the problems described above. Existing devices do not adequately address these problems, particularly those related to vascular trauma and blood clot characteristics.

Means for Solving the Problems

[0007] It is an object of the present design to provide a device and method that satisfy the above requirements. Therefore, it is desirable for a blood clot removal device to remove blood clots from the cerebral arteries of patients suffering from AIS, from the native or graft vessels of patients suffering from MI, from the pulmonary arteries of patients suffering from PE, and from other peripheral arteries and veins where blood clots are causing blockages.

[0008] In some examples, the device includes a clamping feature along the site of the occlusion (e.g., within the internal carotid artery (ICA)). The device can be configured to reperfuse the blood vessel and / or remove blood clots having a fibrin core. In some examples, the fibrin core can be in an intermediate or distal position in a blood clot surrounded by a relatively soft thrombus.

[0009] In some examples, the device is configured to remove blood clots at the M1 bifurcation.

[0010] In some examples, the device is configured to remove blood clots at the M2 bifurcation.

[0011] In some examples, the device includes a first hinge element that includes a holding cell having a first staging section, a folded state, and an expanded state configured to clamp at least a portion of a blood clot, and a second staging section distal to the first staging section, a second hinge strut element that includes a holding cell having a folded state and an expanded state configured to clamp at least a portion of a blood clot, and a third staging section distal to the second staging section, and an outer diameter of the third staging section that is larger than an outer diameter of the second staging section which is larger than an outer diameter of the first staging section.

[0012] In some examples, each staging section includes a plurality of struts that form an array of closed cells.

[0013] In some examples, the device includes a hinge element having a holding cell proximal to the first staging section and connected to the distal end of the shaft.

[0014] In some examples, each holding cell has at least one of a bead, a notch element for embedding a blood clot, or a sinusoidal strut pattern.

[0015] In some examples, the first staging section at least partially extends over an inner body that includes a flow path configured to engage a blood clot and restore blood flow through the blood clot, and the inner body includes a folded state and an expanded state. To define a blood clot receiving space between the inner body and the separate first and second staging sections, the outer diameters of the first and second staging sections are larger than the outer diameter of the inner body in the deployed configuration. The device further includes a first blood clot inlet mouth between the first staging section and the second staging section. In some examples, each hinge element is configured to self-align the corresponding staging section for articulation within a bend of the vasculature.

[0016] In some examples, the first scaffold section is eccentrically coupled on top of the inner body. In some examples, the second scaffold section at least partially extends over the inner body including a flow path configured to engage a blood clot and restore blood flow through the blood clot, and the inner body of the second scaffold section includes a folded state and an expanded state. Each hinge can be the only point of contact between respective blood clot scaffold sections.

[0017] In some embodiments, the proximal end of each respective flow path is joined at the respective proximal end of each respective scaffold section, and the distal end of each respective flow path is joined at each respective subsequent scaffold section.

[0018] In some examples, the second blood clot inlet mouth is positioned between the second scaffold section and the third scaffold section.

[0019] In some examples, each of the first scaffold section, the second scaffold section, and the third scaffold section includes an open distal end.

[0020] In some examples, each of the first scaffold section, the second scaffold section, and the third scaffold section includes a closed proximal end.

[0021] In some examples, each of the first scaffold section, the second scaffold section, and the third scaffold section includes a plurality of struts formed of closed cells, and at least one distal end of at least one of the first scaffold section, the second scaffold section, and the third scaffold section terminates at at least one distal vertex having no connection to an adjacent closed cell of the respective scaffold section.

[0022] In some examples, at least one distal vertex is a petal or leaf member configured to open in a flower shape and expand within one or more branch points of the vasculature to remove the blood clot.

[0023] In some examples, the closed cells of the first scaffold section are smaller than the cells of the second scaffold section.

[0024] In some examples, the closed cells of the second scaffold section are smaller than the cells of the third scaffold section.

[0025] In some examples, each of the first scaffold section, the second scaffold section, and the third scaffold section tapers proximally from an open distal end to a closed proximal end.

[0026] In some examples, each of the first scaffold section, the second scaffold section, and the third scaffold section includes a plurality of struts formed of closed cells, and the distal end of at least one of the first scaffold section, the second scaffold section, and the third scaffold section terminates within a crown without a distal connecting element. At least one of the crowns is configured to pivot open in a flower-like fashion when a blood clot engages it.

[0027] In some examples, by expanding the blood clot removal device, at least one of the clamping cells, the first scaffold section, the second scaffold section, and the third scaffold section deforms at least a portion of the blood clot.

[0028] In some examples, each clamping cell includes a plurality of arcuate strut members, and the plurality of arcuate strut members are configured to actuate and clamp a blood clot from a blood vessel between a pair of arcuate strut members. In some examples, the strut members engage at least a portion of the blood clot and then form a network of struts operable to clamp it. In some examples, the arcuate strut members are positioned around one or more central strut members, and each strut member is joined at a common respective proximal and distal end. In some examples, each of the clamping cells is configured to clamp a blood clot when moving from a folded state to an expanded state of blood clot clamping until a portion of the blood clot is compressed between the respective clamping cells. In some examples, the ratio of the diameter of each clamping cell between the folded state and the expanded state is from about 1.5:1 to 4:1.

[0029] In some examples, the third scaffold section includes a constrained delivery configuration and at least a partially constrained blood clot clamping configuration, and at least a portion of the third scaffold section engages the blood clot in an expanded state and is configured to clamp the blood clot when moving from the expanded state to the blood clot clamping configuration.

[0030] In some examples, the third scaffold section includes a blood clot clamping structure configured to clamp the blood clot when moving from the expanded state to the blood clot clamping configuration.

[0031] In some examples, the blood clot clamping structure includes a helical form.

[0032] In some examples, the blood clot clamping structure includes a non-tubular planar form.

[0033] In some examples, the third scaffold section includes a longitudinal axis, and the blood clot clamping structure extends helically around the longitudinal axis.

[0034] In some examples, the third scaffold section is configured to impart an outward radial force when deployed within a lumen having an inner diameter smaller than the inner diameter of the expanded configuration. In some examples, the outward radial force can vary in a generally sinusoidal pattern along the length of the third scaffold section, and the generally sinusoidal pattern includes a waveform pattern and the amplitude is generally consistent along the length. In some examples, the outward radial force can vary in a generally sinusoidal pattern along the length of the third scaffold section, and the generally sinusoidal pattern includes a wave pattern and the amplitude gradually decreases along the length, being higher at the proximal end of the third scaffold section and lower at the distal end of the third scaffold section.

[0035] In some examples, at least five clamping cells are positioned end-to-end between the proximal and distal ends of the device.

[0036] In some examples, at least three clamping cells are positioned end-to-end between the proximal and distal ends of the device.

[0037] In some examples, a blood clot removal device is disclosed that includes a first hinge element including a clamping cell including a first scaffold section, a folded state, and an expanded state configured to clamp at least a portion of a blood clot, a second scaffold section distal to the first scaffold section, and a second hinge strut element including a clamping cell including a folded state and an expanded state configured to clamp at least a portion of a blood clot, the second hinge strut element being distal to the second scaffold section and including a third scaffold section.

[0038] In some examples, a method for removing a blood clot is disclosed. The method includes delivering a blood clot removal device into or near a site of the blood clot within a blood vessel, the blood clot removal device including a folded state and an expanded state and including a first hinge element including a clamping cell including a first scaffold section, a folded state, and an expanded state configured to clamp at least a portion of a blood clot, a second scaffold section distal to the first scaffold section, and a second hinge strut element including a clamping cell including a folded state and an expanded state configured to clamp at least a portion of a blood clot, the second hinge strut element being distal to the second scaffold section and including a third scaffold section. The method includes embedding at least one of the cells and the scaffold sections together with at least a portion of the blood clot into a blood clot receiving space by expanding the blood clot removal device from the folded state to the expanded state, and removing at least a portion of the blood clot by retrieving the blood clot removal device.

[0039] In some examples, the outer diameter of the third scaffold section is greater than the outer diameter of the second scaffold section, which is greater than the outer diameter of the first scaffold section.

[0040] In some examples, the outer diameter of the third scaffold section is approximately equal to the outer diameter of the second scaffold section, which is approximately equal to the outer diameter of the first scaffold section.

[0041] In some examples, the method includes positioning at least five clamping cells end-to-end in succession.

[0042] In some examples, the method includes positioning at least three clamping cells end-to-end in succession.

[0043] In some examples, the embedding step further includes expanding at least one of a first scaffold section, a second scaffold section, and a third scaffold section and biasing at least a portion of the blood clot into the blood clot receiving space.

[0044] In some examples, the method includes recoating at least partially over the device and gripping, clamping, and / or tweezing the blood clot by at least one of a cell or a section.

[0045] In some examples, the method includes capturing at least a portion of the blood clot using a first scaffold section.

[0046] In some examples, the method includes capturing at least a portion of the blood clot using a second scaffold section.

[0047] In some examples, the method includes capturing at least a portion of the blood clot using a third scaffold section.

[0048] In some examples, the method includes clamping, gripping, and / or tweezing at least a portion of the blood clot using at least one of one or more clamping cells.

[0049] In some examples, the method includes expanding the blood clot removal device such that the scaffold section deforms at least a portion of the blood clot between an inlet between a first and a second scaffold section and / or between an inlet between a second and a third scaffold section.

[0050] In some examples, the third scaffold section includes a constrained delivery configuration and at least a partially constrained blood clot clamping configuration, and the method includes engaging and clamping a blood clot upon movement from an expanded state to the blood clot clamping configuration by at least a portion of the third scaffold section.

[0051] In some examples, the method includes applying an outward radial force by the third scaffold section when deployed within a lumen having an inner diameter smaller than the inner diameter of the expanded state.

[0052] In some examples, the method includes varying the outward radial force in a generally sinusoidal pattern along the length of the third scaffold section, the generally sinusoidal pattern including a waveform pattern, the amplitude being generally consistent along the length.

[0053] In some examples, the method includes varying the outward radial force in a generally sinusoidal pattern along the length of the third scaffold section, the generally sinusoidal pattern including a waveform pattern, the amplitude decreasing gradually along the length, being higher at the proximal end of the third scaffold section and lower at the distal end of the third scaffold section.

[0054] In some examples, the method includes terminating at least one distal end of the first scaffold section, the second scaffold section, and the third scaffold section at at least one distal apex having no connection to an adjacent closed cell of the respective scaffold section.

[0055] In some examples, the method includes opening at least one distal apex in a flower-like pattern in the expanded state and expanding at least one distal apex within one or more branch points of the vasculature structure to remove a blood clot, wherein at least one distal apex is a valve or leaf-like member hingedly connected to at least one strut of the respective scaffold section.

[0056] In some examples, the method includes extending at least a portion of a first scaffold section over an inner body that includes a flow path configured to engage a blood clot and restore blood flow through the blood clot, the inner body including a folded state and an expanded state, and defining a blood clot receiving space between the inner body and a separate first scaffold section and a second scaffold section, wherein an outer diameter of the first scaffold section and the second scaffold section is greater than an outer diameter of the inner body in a deployed configuration, and the device further includes a first scaffold inlet mouth between the first scaffold section and the second scaffold section.

[0057] In some examples, the method includes self-aligning corresponding scaffold sections such that each hinge element articulates within a bend of the vasculature.

[0058] In some examples, the method includes eccentrically coupling a first scaffold section over the inner body.

[0059] Other aspects and features of the present disclosure will become apparent to those of ordinary skill in the art upon consideration of the following detailed description in conjunction with the accompanying figures. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] The foregoing and further aspects of the present disclosure will be further considered in conjunction with the following description of the accompanying drawings, in which like numerals in the various drawings indicate like structural elements and features. The drawings are not necessarily to scale, and instead emphasis is placed on illustrating the principles of the present disclosure. The figures depict one or more implementations of the device of the invention by way of example and not limitation. Those of ordinary skill in the art will envision combinations of elements from the various figures that better suit their user requirements.

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DETAILED DESCRIPTION OF THE INVENTION

[0061] Specific embodiments of the present disclosure will now be described in detail with reference to the drawings, where like reference numerals indicate functionally similar or identical elements. The embodiments address many of the deficiencies associated with conventional catheters, such as inefficient blood clot removal and inaccurate deployment of the catheter to the target site.

[0062] Accessing various blood vessels within the vasculature, regardless of whether they are coronary, pulmonary, or cerebral vessels, involves well-known procedures and the use of numerous conventional commercially available accessory products. These products, such as angiographic substances and guidewires, are widely used in diagnostic and medical procedures. When these products are used in conjunction with the systems and methods of the present disclosure in the following description, their functions and exact configurations are not described in detail.

[0063] The following detailed description is merely exemplary in nature and is not intended to limit the present disclosure or the application and use thereof. The description of the present disclosure is often in the context of procedures involving intracranial arteries, but the present disclosure may also be used in other body passages as described above.

[0064] Having illustrated and described specific embodiments of the present disclosure above, it will be apparent from the above description that various changes can be made without departing from the spirit and scope of the present disclosure. For example, the embodiments described herein refer to specific features, but the present disclosure includes embodiments having combinations of different features. The present disclosure also includes embodiments that do not include all of the specific features described. Specific embodiments of the present disclosure are hereinafter described in detail with reference to the drawings, and the same reference numerals indicate the same or functionally similar elements. The terms "distal" or "proximal" are used in the following description with respect to the position or direction relative to the treating physician. "Distal" or "distally" refers to a position away from or a direction away from the physician. "Proximal" or "proximally" or "proximate" refers to a position near or a direction toward the physician.

[0065] Accessing the brain, coronary arteries, and pulmonary veins involves using numerous commercially available products and conventional procedures. Accessory products such as guidewires, guide catheters, angiographic catheters, and microcatheters are described elsewhere and are routinely used in catheterization procedures. In the following description, it is assumed that these products and methods are used in conjunction with the devices and methods of the present disclosure and need not necessarily be described in detail.

[0066] The following detailed description is merely exemplary in nature and is not intended to limit the present disclosure, or the application and use of the present disclosure. The description of the present disclosure is often in the context of treating intracranial arteries, but the present disclosure can also be used in other body passages as described above.

[0067] A common theme across many of the disclosed designs is that, in some cases, the device can include an outer expandable member, and sometimes an inner expandable member can be included within the outer expandable member, and both the inner expandable member and the outer expandable member are of a multi-layered structure directly or indirectly connected to an elongate shaft. Referring to FIG. 1, one exemplary device 100 according to the present disclosure is shown. Specifically, device 100 is shown in a side view with the proximal end 104 of device 100 connected to the distal end of an elongate shaft 106. As shown, the distal end of shaft 106 extends into the artery and its proximal end extends outside the artery. Device 100 can include a plurality of clamping cells 150 including a first cell 150 at or near the proximal end 104 and connected to shaft 106. The first cell 150 may be integral with shaft 106 or separate. The first clamping cell 150 is connected to a first scaffold section 110 and can be configured to embed, grip, clamp, and / or "pinch" a blood clot as specifically shown and described by FIGS. 2A - 3B. As discussed herein, the terms "pinching" or "pinched" are intended to refer to the clamping or squeezing of cells where the respective struts come together to pinch at least a portion of the blood clot (e.g., bringing the cells of section 130 or cell 150 itself closer). In this regard, the number of struts in each cell need not be limited, but at least two strut surfaces must be included to pinch the corresponding blood clot material.

[0068] The shaft 106 can be a tapered wire shaft and may be made of stainless steel, MP35N, nitinol, or other materials preferably having a high modulus of elasticity and tensile strength. The shaft 106 may also have an indication for one or more bands proximal to the patient for instructing the patient when the distal end of the device 100 is approaching the end of the microcatheter during insertion.

[0069] Section 110 can include a folded configuration for delivery and an expanded configuration for blood clot retrieval, blood flow restoration, and / or fragmentation protection. To move between the delivery configuration and the expanded configuration, section 110 is configured to self-expand to a diameter larger than the diameter of member 103 during delivery from the microcatheter (e.g., release from the microcatheter). Section 110 can include an outer expandable body having an inner expandable member 103 with a generally tubular inner flow path to facilitate restoration of blood flow through the blood clot immediately after the blood clot retrieval device 100 is deployed at the occlusion site. Expansion of the outer expandable body of section 110 can cause compression and / or displacement of the blood clot during expansion. The inner channel of member 103 may also include a portion that compresses the region of the blood clot to form a blood communication channel across the blood clot C. Such a channel can serve to reduce the pressure gradient across the blood clot C and reduce one of the forces that must be overcome to retract the blood clot C. The flow path of member 103 can also serve as a flow path for oxygenated nutrient-carrying blood to reach the ischemic region distal to the blood clot.

[0070] The outer expandable body of section 110 can provide a high-level scaffold that provides an escape route or opening to urge the blood clot towards the opening or blood clot inlet 115. When there is an inlet opening 115 within the outer expandable body of section 110 and / or between the outer expandable body and member 103, it provides the main degrees of freedom of movement available to the blood clot. Thus, the expansion of section 110 urges the blood clot into the receiving space defined between member 103, the outer expandable body, and any distal blood clot scaffold section(s). The inlet(s) 115 are configured to allow portions of the blood clot to enter the receiving space between each respective outer expandable body of section 110 and member 103 and to allow the blood clot to be retrieved without being overly compressed.

[0071] This is advantageous because compression of the blood clot dehydrates the blood clot, but in turn increases the frictional properties of the blood clot and its rigidity, all of which make it more difficult for the blood clot to detach from and be removed from the blood vessel. This compression can be avoided when the blood clot moves inwardly through the outer wall of section 110 as the porous structure moves outwardly towards the blood vessel wall. In some examples, the struts of sections 110, 120, and / or 130 include a relatively low coefficient of friction through polishing, hydrophilic coating, PTFE coating, silicone lubricant, etc., such that the blood clot can easily slide from these segments and through the corresponding inlet(s) 116 into the receiving space.

[0072] As shown, the device 100 can include a second scaffold section 120 and a third scaffold section 130, each including an outer expandable body that is structurally similar to that of section 110. However, the outer diameter of section 130 can be larger than the outer diameter of section 120 which can be larger than the outer diameter of section 110. Sections 110, 120, 130 are preferably made of a superelastic or pseudoelastic material (nitinol or another memory alloy having high recoverable strain).

[0073] However, device 100 is not so limited and may instead be constructed from other material(s). As such, by selectively organizing and sizing sections 110, 120, 130, device 100 is configured to capture different blood clot types. In some embodiments, the outer diameter of section 130 may be sized to be the same as the diameter of the blood vessel into which it is delivered to easily capture any fragment and avoid distal embolization. The outer diameter of section 120 may be relatively small, but the outer diameter of section 110 may be even smaller to more easily capture larger blood clots (e.g., fibrin-rich blood clots). Advantageously, a smaller diameter of section 110 can prevent damage to the blood vessel when the blood clot is fibrin-rich and / or when the blood clot rolls over during retrieval. In some examples, section 110 may be beneficial in clot retention within device 100.

[0074] In some examples, by gradually increasing the diameters of sections 120, 130, fragments from the crushable portion of the blood clot can be firmly captured. Thus, varying the diameters of sections 110, 120, 130 as described and shown can be particularly advantageous for capturing blood clot fragments that section 110 might otherwise miss during use. Sections 110, 120, 130 can be particularly advantageous for minimizing the risk of damage to the blood vessel wall during blood clot retrieval. For example, when the blood clot is relatively large, a smaller diameter of the corresponding device 100 allows space for the large blood clot and can minimize or reduce the friction between the blood clot and the blood vessel wall during blood clot removal. Device 1 can also facilitate blood clot capture when the blood clot rolls over during use of device 100 or when the blood clot changes shape during retrieval.

[0075] Furthermore, the outer diameters of sections 110, 120, and 130 can vary and / or can be substantially similar otherwise. For example, section 120 can include the inner member 103, while section 130 need not necessarily include any inner member 103 and, instead, can include a substantially open distal end that terminates at one or more distal crowns or vertices 136 that are not connected to any cell or element of section 130. Similarly, sections 110 and 120 can each include a substantially open distal end that terminates at one or more distal crowns or vertices 116, 126 that are not connected to any cell or element of their respective sections 110, 120.

[0076] Section 130 can be configured to include one or more struts configured to sandwich the blood clot C. In some examples, the sandwiching of section 130 can be achieved by advancing a microcatheter or an intermediate catheter over the device until a portion of the blood clot is compressed between the distal tip of the catheter and the crown or strut (e.g., vertex 136) of section 130. The diameter of section 130 can vary up to about 150% of the diameter of the blood vessel BV with the blood clot C. For example, the microcatheter can be advanced distally to sandwich a portion of the blood clot between the distal tip of the microcatheter and section 130 adjacent to the low radial force region. Section 130, which is distal to sections 110, 120, provides additional gripping and control of the distal end of the blood clot C during movement and retention. The strut members and the corresponding cells of section 130 can include various shapes and designs configured to sandwich fibrin-rich blood clots, including those described in U.S. Patent Nos. 10,292,723, 10,363,054, U.S. Patent Application Nos. 15 / 359,943, 16 / 021,505, and 16 / 330,703, each of which is hereby incorporated by reference in its entirety as if expressly set forth herein.

[0077] Compression of the blood clot by section 130 of the present disclosure and / or one or more cells 150 may modify the properties of the blood clot such that, as described in International Publication No. WO 2012 / 120490 (A), the entire content of which is incorporated herein by reference, the blood clot becomes harder and "more sticky", making it more difficult to retrieve the blood clot. The device 100 of the present disclosure is intended to facilitate blood clot retrieval by engaging the blood clot across the surface area and expanding between the blood clot and the vessel wall in such a way that it is done with minimal compression of the blood clot. In some embodiments, the clamping can be achieved by advancing a microcatheter or an intermediate catheter over the device until a portion of the blood clot is compressed between the catheter and the cell 150 or section 130. However, the operation of each cell 150 or section 130 is also not so limited and can be carried out, for example, by pulling one or two pull members attached thereto and delivering an electric current to one or more strut members of each cell 150 or section 130 to change from a folded configuration to a clamped configuration. This clamping increases the gripping force of the device on the blood clot, especially on a fibrin-rich blood clot, facilitating removal of the blood clot. This can also stretch the blood clot and reduce the force required for movement by pulling the blood clot away from the vessel wall during the process of moving it.

[0078] The segmentation of cell 150 and the hinge design between sections 110, 120, and 130 are also specifically adjusted to achieve attachment at the bend in the vasculature. The only connecting member of device 100 is cell 150, which functions as a hinge element configured to self-align with the neutral axis and allow the device to articulate easily at the bend. In some examples, each of member 103 and cell 150 shown in FIG. 1 is laser cut from a single microtube having an outer diameter smaller than the inner diameter of the folded outer member when the outer member is loaded into the microcatheter. The opening angle of the cells of the inner tube is configured such that when moving from the folded configuration to the expanded configuration, the change (or shortening) in the length of the inner tube is the same as that of the outer member, facilitating the connection between the distal ends of both the inner and outer members.

[0079] As described throughout this document, a design scope is envisioned for each of these elements, and any of these elements is intended to be used with any other element, but for the sake of avoiding repetition, not all possible combinations of these elements are shown. Sections 110, 120, and 130 are preferably made of a material that can automatically recover its shape when released from a severely distorted delivery configuration. Superelastic materials such as nitinol or alloys having similar properties are particularly suitable. The material can be in many forms such as wire or strip or sheet or tube. A particularly suitable manufacturing process is to laser cut a nitinol tube and then heat treat and electropolish the resulting structure to create the framework of struts and connection elements. This framework can be made into any of a wide variety of shapes as disclosed herein and may be visualized under fluoroscopy by the addition of alloying elements (e.g., platinum) or by various other coatings or marker bands.

[0080] Figure 2A shows an enlarged view of an exemplary clamping cell 250 similar to the cell 250 of the device 100. Each of the cells 250 can be configured to embed and / or engage with a blood clot and grip the blood clot so as to securely hold the blood clot for retraction. It is understood that each of the clamping cells described herein can be used compatibly with a blood clot retrieval device, as needed or required. The cell 250 can include a proximal end 204 and a distal end 208 with the strut members 212a, 212, 212c, and 212d positioned therebetween. One or more than one of the strut members 212a, 212b, 212c, and 212d can be arcuate or otherwise configured to include a tensioned bend such that it can be embedded in the blood clot and then actuated by gripping or clamping the blood clot during use. The cell 250 can be actuated into a clamping configuration by being pulled or actuated by one or more pull members or by having its covering removed from a sheath (e.g., a microcatheter), and delivering an electric current to one or more than one of the strut members 212a, 212, 212c, and 212d such that at least a first portion of one or more than one of the strut members 212a, 212, 212c, and 212d changes from a folded configuration to a clamping configuration.

[0081] The diameter of the cell 250 can range from about 2 to 10 millimeters, depending on how much the design profile allows. One preferred diameter can be about 2.25 millimeters. In some examples, the cell 250 can be small enough to fit a 0.021 or 0.018 inch ID microcatheter.

[0082] FIG. 2B shows an enlarged view of another exemplary clamping cell 250' having strut members 212a', 212b', and 212c' shown with undulating edges. These undulations can be formed by heat setting, crimping, or otherwise formed as needed or required. FIG. 2C shows an enlarged view of another exemplary clamping cell 250'' having strut members 212a'', 212b'', and 212c'', each having one or more stitches.

[0083] FIG. 3B shows an enlarged view of another exemplary clamping cell 350 having strut members 312a, 312b, and 312c shown with relatively straight, non-curved strut members interconnected between ends 304, 308. These undulations can be formed by heat setting, crimping, or otherwise formed as needed or required. FIG. 3C shows an enlarged view of another exemplary clamping cell 350' having strut members 312a', 312b', and 312c', each including one or more notches or indentations.

[0084] Returning to device 100, FIG. 4 shows a side view of device 100 in an exemplary blood vessel BV used with an exemplary blood clot C, with device 100 shown at an initial blood clot position engaged with blood clot C in section 110. That section 120 is shown to engage when blood clot C rolls over and fragments distally, such that fragments of blood clot C are captured by section 130. The device 100 of FIG. 4 also includes a first clamping cell 150 proximal to section 110, a second clamping cell 150 between sections 110, 120, and a third clamping cell 150 between sections 120, 130. Each cell 150 provides enhanced gripping of blood clot C and any of its fragments. Each of the cells 150 may be particularly advantageous for capturing a blood clot that may have a fibrin core at a central, distal, or proximal position within blood clot C. Further, in use, if one cell 150 fails to grip a portion of blood clot C, one or more cells 150 distal to that one cell 150 can engage and / or grip blood clot C.

[0085] FIG. 5A shows a side view of device 100 in blood vessel BV used with blood clot C after the process shown in FIG. 4. As shown, blood clot C engages between and / or with compartments 110, 120 such that device 100 is clearly configured to capture both fibrin-rich blood clots and erythrocyte-rich blood clots that are crushable. The overall design of the device will help facilitate the capture of fibrin-rich blood clots and erythrocyte-rich blood clots. The three clamping segments will help capture blood clots where the fibrin-rich core may be located anywhere within the blood clot. An increase in the diameter of the device will help reduce fragmentation of the blood clot. Between sections 110, 120, cells 150 are also engaged with blood clot C. In FIG. 5B, device 100 is covered by microcatheter 70 and blood clot C is tightly gripped and / or clamped to cells 150 by pulling cells 150 within microcatheter 70 until resistance is felt, which symbolizes that the blood clot is tightly gripped within cells 150. Blood clot C can be secured by suction through microcatheter 70.

[0086] FIG. 6A shows a side view of an exemplary device 100 of an exemplary blood clot C in a blood vessel BV. FIG. 6B shows a side view of the device 100 of FIG. 6A after actuation of the angled features associated with one or more distal crowns or vertices 116’, 126’. The devices of FIGS. 6A-6B are particularly useful for capturing blood clots at vascular branch points that are difficult to remove with one of the prior art stent retriever devices. For purposes of this application, when a blood clot is present within two different branches (e.g., M1 and M2) of the blood vessel BV, the blood vessel BV is referred to as the “main vessel” and the other branches that have blood clots but no stent retrievers are referred to as “minor vessels”. Through the angled features of one or more distal crowns or vertices 116’, 126’ of sections 110, 120, the outer cage is configured to open around the branch point. When one or more distal crowns or vertices 116’, 126’ of sections 110, 120 are angled as shown between FIGS. 6A-6B, the outer cages of each respective section 110, 120 open and expand in a flower-like manner (e.g., by pivoting about one or more strut junctions, connections, or hinge elements as shown in FIG. 6A by the large rotation arrows) such that the struts associated with each respective distal crown or vertex 116’, 126’ capture the blood clot at the branch point.

[0087] Furthermore, these angled features of one or more distal crowns or vertices 116’, 126’ of sections 110, 120 can cause an increase in the outer diameter of sections 110, 120 that enhances the gripping of the blood clot C at the branch point when the blood clot C is gripped between the inner and outer cages of sections 110, 120. When a blood clot is present at the branch point, the three clamping features can facilitate blood clot gripping and / or clamping in each different branch of the blood vessel. The progressively increasing diameter of the outer cage between sections 110, 120, 130 and their respective inner segments (e.g., member 103, cell 150, etc.) can maintain the blood clot C in a retained state within the blood vessel BV. The microcatheter 70 and the recoating of the device 100 by suction therethrough can also improve the gripping of the blood clot C in the device 100 present at the branch point.

[0088] Referring to FIG. 7A, apparatus 100' is shown, which is similar to apparatus 100. Apparatus 100' includes five consecutively positioned hinge elements, including at least one of sections 110 and 120, and clamping cell 150. The outer diameters of sections 110, 120, and 130, which are similar to those of apparatus 100, gradually increase, being smallest in section 110 and largest in section 130. Although not shown, the inner body 103 having corresponding flow channels may be included in at least one of sections 110 and 120 similar to those of apparatus 100. Positioning cell 150 as shown can facilitate manufacturing and enhance gripping of the blood clot via additional cell 150. Increasing the diameter between sections 110, 120, and 130 can prevent fragmentation of the blood clot.

[0089] Referring to FIG. 7B, apparatus 100'' is shown, which is similar to apparatus 100', the main difference being that all three sections 110'', 120'', 130'' have approximately the same diameter. For the inner segments (e.g., cell 150, inner body 103, etc.), a single tube for a shape memory alloy (e.g., nitinol), and any of apparatuses 100, 100', and 100'' from a single tube of shape memory alloy can be used to manufacture the outer tubes corresponding to sections 110, 120, 130. In some examples, a relatively small gap may be provided between sections 110, 120, and cell 150 to form a blood clot inlet mouth and expose cell 150 to the blood clot(s).

[0090] FIG. 8 is a flow diagram illustrating a method of removing a blood clot from a patient's blood vessel according to an aspect of the present disclosure. The method steps of FIG. 8 can be implemented by any of the exemplary means described herein or by similar means, as will be understood. Referring to method 8000 outlined in FIG. 8, in step 8010, a blood clot removal device is delivered into a blood vessel at or near the site of the blood clot, the blood clot removal device including a first hinge element including a first scaffold section and a clamping cell including a folded state and an expanded state configured to clamp at least a portion of the blood clot, a second scaffold section distal to the first scaffold section, and a second hinge strut element including a clamping cell including a folded state and an expanded state configured to clamp at least a portion of the blood clot, the second hinge strut element being distal to the second scaffold section. In step 8020, method 8000 includes embedding at least one of the cells and the scaffold sections together with at least a portion of the blood clot into a blood clot receiving space by expanding the blood clot removal device from a folded state to an expanded state. In step 8030, method 8000 includes removing at least a portion of the blood clot by retrieving the blood clot removal device. Method 8000 can end after step 8030. In other embodiments, additional steps according to the above-described examples can be performed.

[0091] The present disclosure is not limited to the described examples, which can vary in configuration and detail. The terms "distal" and "proximal" are used throughout the foregoing description and are meant to refer to the position and direction with respect to the treating physician. Thus, "distal" or "distally" refers to a position away from or a direction away from the physician. Similarly, "proximal" or "proximally" refers to a position near or a direction toward the physician.

[0092] In the description of the embodiments, technical terms are used for the sake of clarity. Each term is intended to have its broadest meaning as understood by those skilled in the art and is intended to include all technical equivalents that act in a similar manner to achieve a similar purpose. It should also be understood that a reference to one or more steps of a method does not exclude the presence of additional method steps or method steps intervening between those explicitly identified. Each step of the method can be performed in an order different from the order described herein without departing from the scope of the disclosed technology. Similarly, a reference to one or more components in an apparatus or system does not exclude the presence of additional components or components intervening between those explicitly identified.

[0093] As used herein, a "patient" or "subject" can be a human or any animal. It should be understood that the animal can be of various applicable types including, but not limited to, mammals, veterinary animals, livestock animals, or pet animals. By way of example, the animal can be an experimental animal (e.g., rat, dog, pig, monkey, etc.) specifically selected to have certain properties similar to humans.

[0094] As used herein, the term "about" or "approximately" with respect to any numerical value or range of numerical values indicates a reasonable dimensional tolerance that allows a part of a component or a set of components to function in accordance with its intended purpose as described herein. More specifically, "about" or "approximately" may refer to a range of values that are ±20% of the recited value. For example, "about 90%" may refer to a range of values from 71% to 99%.

[0095] As used herein, the terms "comprising", "containing", or "including" mean that at least the specified compound, element, particle, or method step is present in a composition, article, or method, but do not exclude the presence of other compounds, materials, particles, or method steps, even if they have the same function as the specified ones.

[0096] It should also be noted that in this specification and the appended claims, the singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise. Ranges can be expressed herein from one specific value of "about" or "approximately" to another specific value of "about" or "approximately". When expressing such ranges, other exemplary embodiments also include from one specific value to another specific value.

[0097] The descriptions contained herein are examples of the present disclosure and are not intended to limit the scope of the present disclosure in any way. Although specific embodiments of the present disclosure are described, various modifications can be made to the apparatus and method without departing from the scope and spirit of the present disclosure. For example, the embodiments described herein refer to specific components, but the present disclosure utilizes various combinations of components to achieve the described functionality, utilizes alternative materials to achieve the described functionality, combines components from various embodiments, combines components from various embodiments with known components, etc., including other embodiments. The present disclosure contemplates replacing the component parts illustrated herein with other well-known commercially available products. Such modifications are often apparent to those skilled in the art related to the present disclosure and are intended to be within the scope of the following claims.

[0098] 〔Embodiments〕 (1) A blood clot removal device, a first scaffold section, A first hinge element including a clamping cell including a folded state and an expanded state configured to clamp at least a portion of the blood clot, only a second staging section distal to the first staging section, A second hinge strut element including a clamping cell including a folded state and an expanded state configured to clamp at least a portion of the blood clot, only a third staging section distal to the second staging section, An outer diameter of the third staging section that is larger than an outer diameter of the second staging section that is larger than an outer diameter of the first staging section, a blood clot removal device. (2) The blood clot removal device according to embodiment 1, further including a hinge element including a clamping cell proximal to the first staging section and connected to the distal end of the shaft. (3) The blood clot removal device according to embodiment 2, wherein each clamping cell includes at least one of a bead, a notch element for embedding the blood clot, or a sinusoidal strut pattern. (4) The first staging section at least partially extends over an inner body including a flow path configured to engage the blood clot and restore blood flow through the blood clot, the inner body including a folded state and an expanded state, To define a blood clot receiving space between the inner body and the separate first staging section and the second staging section, the outer diameters of the first staging section and the second staging section are larger than the outer diameter of the inner body in the deployed configuration, and the device The blood clot removal device according to embodiment 1, further including a first blood clot inlet mouth between the first staging section and the second staging section. (5) Each hinge element is configured to self-align the corresponding staging section for articulation within a bend of the vascular structure, the second staging section at least partially extends over an inner body including a flow path configured to engage the blood clot and restore blood flow through the blood clot, the inner body of the second staging section including a folded state and an expanded state, The clot removal device according to embodiment 4, wherein each hinge element is the only contact point between the respective clot scaffold sections.

[0099] (6) The clot removal device according to embodiment 5, wherein the proximal end of each respective flow path is joined at the respective proximal end of each scaffold section, and the distal end of each respective flow path is joined at each subsequent scaffold section. (7) Each of the first scaffold section, the second scaffold section, and the third scaffold section includes an open distal end. The clot removal device according to embodiment 4, wherein each of the first scaffold section, the second scaffold section, and the third scaffold section includes a plurality of struts formed of closed cells, and at least one of the distal ends of the first scaffold section, the second scaffold section, and the third scaffold section terminates at at least one distal vertex having no connection to an adjacent closed cell of the respective scaffold section. (8) The clot removal device according to embodiment 7, wherein the at least one distal vertex is an open petal-shaped or leaf-shaped member configured to expand at one or more branch points of the vasculature structure to remove the clot in a flower-like pattern. (9) Each of the first scaffold section, the second scaffold section, and the third scaffold section includes an open distal end, each of the first scaffold section, the second scaffold section, and the third scaffold section includes a plurality of struts formed of closed cells, and at least one of the distal ends of the first scaffold section, the second scaffold section, and the third scaffold section terminates within a crown without a distal connection element, and at least one of the crowns is configured to pivot open in a flower-like pattern when a clot engages therewith. The clot removal device according to embodiment 4. (10) The device according to embodiment 4, wherein at least one of the clamping cell, the first scaffold section, the second scaffold section, and the third scaffold section is configured to deform at least a portion of the blood clot by expanding the blood clot removal device.

[0100] (11) Each clamping cell includes a plurality of arcuate strut members, the plurality of arcuate strut members being configured to actuate and clamp the blood clot from the blood vessel between a pair of the arcuate strut members, the strut members engaging at least a portion of the blood clot and then being operable to form a network of struts to clamp it, the blood clot removal device according to embodiment 1. (12) The ratio of the diameter of each clamping cell between the folded state and the expanded state is about 1.5:1 to 4:1, the blood clot removal device according to embodiment 11. (13) The third scaffold section includes a constrained delivery configuration and at least a partially constrained blood clot clamping configuration, at least a portion of the third scaffold section engaging the blood clot in the expanded state and being configured to clamp the blood clot upon movement from the expanded state to the blood clot clamping configuration, the blood clot removal device according to embodiment 1. (14) The blood clot removal device according to embodiment 13, wherein the third scaffold section includes a blood clot clamping structure configured to clamp the blood clot upon movement from the expanded state to the blood clot clamping configuration. (15) The third scaffold section is configured to apply an outward radial force when deployed within a lumen having an inner diameter smaller than the inner diameter in the expanded state, the outward radial force varying in a generally sinusoidal pattern along the length of the third scaffold section, the generally sinusoidal pattern including a wave pattern and the amplitude being generally consistent along the length, the blood clot removal device according to embodiment 1.

[0101] (16) At least five clamping cells are positioned end-to-end between the proximal end and the distal end of the device, the blood clot removal device according to embodiment 1. (17) A method for removing a blood clot, comprising: delivering a blood clot removal device into a blood vessel at or near the site of the blood clot, the blood clot removal device including a folded state and an expanded state, a first scaffold section, a first hinge element including a clamping cell including a folded state and an expanded state configured to clamp at least a portion of the blood clot, and a second scaffold section distal to the first scaffold section; a second hinge strut element including a clamping cell including a folded state and an expanded state configured to clamp at least a portion of the blood clot, and a third scaffold section distal to the second scaffold section; expanding the blood clot removal device from the folded state to the expanded state to embed at least one of the cells and the scaffold section together with at least a portion of the blood clot into a blood clot receiving space; removing at least a portion of the blood clot by retrieving the blood clot removal device. (18) The method according to embodiment 17, further comprising clamping or gripping at least a portion of the blood clot using at least one of the one or more clamping cells. (19) The third scaffold section includes a constrained delivery configuration and at least a partially constrained blood clot clamping configuration, and the method includes: engaging and clamping the blood clot by at least a portion of the third scaffold section when moving from the expanded state to the blood clot clamping configuration. (20) terminating at least one distal end of at least one of the first scaffold section, the second scaffold section, and the third scaffold section at at least one distal apex without connection to an adjacent closed cell of the respective scaffold section; opening the at least one distal apex in a flower-like pattern in the expanded state; To remove the clot, expanding the at least one distal apex at one or more branch points of the vascular structure, wherein the at least one distal apex is a petal-shaped or leaf-shaped member hingedly connected to at least one strut of each respective scaffold section, the method of embodiment 17 further comprising expanding.

Claims

1. A blood clot removal device, a first scaffold section, a second scaffold section distal to the first scaffold section, a first hinge element connecting the first scaffold section and the second scaffold section, the first hinge element including a clamping cell including a folded state and an expanded state configured to clamp at least a portion of the blood clot, a third scaffold section distal to the second scaffold section, a second hinge strut element connecting the second scaffold section and the third scaffold section, the second hinge strut element including a clamping cell including a folded state and an expanded state configured to clamp at least a portion of the blood clot, and an outer diameter of the third scaffold section that is larger than an outer diameter of the second scaffold section that is larger than an outer diameter of the first scaffold section, the blood clot removal device.

2. The blood clot removal device according to claim 1, further including a hinge element including a clamping cell proximal to the first scaffold section and connected to the distal end of the shaft.

3. The blood clot removal device according to claim 2, wherein each clamping cell includes at least one of a serration, a notch element for embedding the blood clot, or a sinusoidal strut pattern.

4. The first scaffold section at least partially extends over an inner body including a flow path configured to engage the blood clot and restore blood flow through the blood clot, the inner body including a folded state and an expanded state, the outer diameters of the first scaffold section and the second scaffold section are larger than the outer diameter of the inner body in the expanded state of the inner body to define a blood clot receiving space between the inner body and the separate first scaffold section and the second scaffold section, and the device The blood clot removal device according to claim 1, further including a first blood clot inlet mouth between the first scaffold section and the second scaffold section.

5. Each hinge element is configured to self-align the corresponding scaffold section for articulation within a bend of the vasculature structure, the second scaffold section at least partially extends over an inner body including a flow path configured to engage the blood clot and restore blood flow through the blood clot, and the inner body of the second scaffold section includes a folded state and an expanded state, The blood clot removal device according to claim 4, wherein each hinge element is the only contact point between respective blood clot scaffold sections.

6. The blood clot removal device according to claim 5, wherein the proximal end of each respective flow path is joined at the respective proximal end of each scaffold section, and the distal end of each respective flow path is joined at each subsequent scaffold section.

7. Each of the first scaffold section, the second scaffold section, and the third scaffold section includes an open distal end, Each of the first scaffold section, the second scaffold section, and the third scaffold section includes a plurality of struts formed of closed cells, and at least one of the distal ends of the first scaffold section, the second scaffold section, and the third scaffold section terminates at at least one distal vertex having no connection to adjacent closed cells of the respective scaffold section. The blood clot removal device according to claim 4.

8. The blood clot removal device according to claim 7, wherein the at least one distal vertex is opened in a flower-like pattern and is a petal-shaped or leaf-shaped member configured to expand at one or more branch points of the vascular structure to remove the blood clot.

9. Each of the first scaffold section, the second scaffold section, and the third scaffold section includes an open distal end, each of the first scaffold section, the second scaffold section, and the third scaffold section includes a plurality of struts formed of closed cells, and at least one of the distal ends of the first scaffold section, the second scaffold section, and the third scaffold section terminates within a crown without a distal connecting element, and at least one of the crowns is configured to pivot and open in a flower-like pattern when a blood clot engages therewith. The blood clot removal device according to claim 4.

10. The device is configured such that, by expanding the blood clot removal device, at least one of the clamping cells, the first scaffold section, the second scaffold section, and the third scaffold section deforms at least a portion of the blood clot. The blood clot removal device according to claim 4.

11. Each clamping cell is The blood clot removal device according to claim 1, comprising a plurality of arcuate strut members, wherein the plurality of arcuate strut members are configured to actuate and clamp the blood clot from a blood vessel between a pair of the arcuate strut members, and the strut members form a network of struts that are operable to engage at least a portion of the blood clot and then clamp it.

12. The blood clot removal device according to claim 11, wherein the ratio of the diameter of each clamping cell between the folded state and the expanded state is about 1.5:1 to 4:

1.

13. The blood clot removal device according to claim 1, wherein the third scaffold section includes a constrained delivery configuration and at least a partially constrained blood clot clamping configuration, and at least a portion of the third scaffold section engages the blood clot in the expanded state and is configured to clamp the blood clot when moving from the expanded state to the blood clot clamping configuration.

14. The blood clot removal device according to claim 13, wherein the third scaffold section includes a blood clot clamping structure configured to clamp the blood clot when moving from the expanded state to the blood clot clamping configuration.

15. The blood clot removal device according to claim 1, wherein the third scaffold section is configured to apply an outward radial force when deployed within a lumen having an inner diameter smaller than the inner diameter in the expanded state, and the outward radial force varies in a generally sinusoidal pattern along the length of the third scaffold section, the generally sinusoidal pattern includes a wave pattern, and the amplitude is generally consistent along the length.

16. The blood clot removal device according to claim 1, wherein at least five clamping cells are positioned end-to-end between the proximal end and the distal end of the device.

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