Intravascular device with radiopaque body markers - Patents.com

Abstract

To provide intravascular therapeutic treatment devices.SOLUTION: An intravascular treatment device is presented having an expandable frame made up of circular struts, straight struts, and bent struts forming a frame with circumference that varies over the length of the frame. Radiopaque markers can be positioned on the bent struts to indicate outer circumferences of the frame along the length of the frame. The device can be a stent or a clot retriever. If the device is a clot retriever, the proximal end of the expandable frame can be attached to a guide wire and the distal end of the expandable frame can be free to slide over the guide wire when the frame moves from a collapsed state to an expanded state and vice versa.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates generally to endovascular treatment devices, and more particularly to an expandable stent and clot retriever having radiopaque body markers. [Background technology]

[0002] Intravascular devices such as stents and clot retrievers come in a variety of shapes, sizes, and configurations. Considerations in the design of stents and clot retrievers include the goal of treatment, the location of the treatment site, and the geometry of the treatment site. A stent or clot retriever may require a degree of flexibility to navigate the vessel to reach the treatment site, and in the case of a clot retriever, to retreat intact through the vessel where the clot is. A stent may require a degree of structural integrity to support the body cavity or embolic implant, and a clot retriever may require a degree of structural integrity to expand around or through the clot. A stent or clot retriever may require a degree of conformability to properly expand within a curved vasculature. Finally, a degree of radiopacity may also be required to allow the physician to properly position the intravascular device.

[0003] Flexibility, structural integrity, conformability, and radiopacity are often competing design goals. Unfortunately, in many applications, radiopaque materials do not have optimal material properties to meet the design goals of flexibility, structural integrity, and conformability, and devices made from materials that contribute to these goals, such as Nitinol and other shape memory metals, may have poor radiopacity, making it difficult for physicians to visualize the positioning of the device during treatment. To meet the competing goals, devices are typically constructed primarily of materials such as Nitinol to achieve flexibility, structural integrity, and conformability, and radiopaque materials are added. However, incorporating radiopaque materials into the body of an intravascular device is difficult, especially in devices designed for extreme flexibility, structural integrity, conformability, or small size. Summary of the Invention [Problem to be solved by the invention]

[0004] Therefore, there is a need for improved or alternative intravascular devices having radiopaque markers. [Means for solving the problem]

[0005] It is an object of the present invention to provide systems, devices, and methods that meet the above-mentioned needs. In general, it is an object of the present invention to provide an endovascular treatment device having an expandable frame composed of circular, straight, and bent struts that form a frame with a circumference that varies over the length of the frame. Radiopaque markers may be positioned on the bent struts to indicate the circumference of the frame along the length of the frame. The device may be a stent or a clot retriever. If the device is a clot retriever, the proximal end of the expandable frame may be attached to a guidewire and the distal end of the expandable frame may be free to slide over the guidewire as the frame moves from a collapsed state to an expanded state, and vice versa.

[0006] An exemplary endovascular treatment device may include an elongate guide and an expandable framework that is movable from a collapsed configuration, where the framework may be sized to traverse through a lumen of a catheter, and in the expanded configuration, where the framework may be sized to extend radially within a lumen of a blood vessel.

[0007] The expandable framework may be constructed from annular struts, central struts, and bent struts. Each of the annular struts may be positioned to surround the elongated guide such that each annular strut has a proximally adjacent annular strut and another distally adjacent annular strut, except for the most distal and most proximal annular struts, each of which has only one adjacent annular strut. The central strut may be positioned to join each annular strut to one adjacent annular strut, and the bent struts may be positioned to join each annular strut to its opposing adjacent annular strut. When the expandable framework is in the collapsed configuration, each of the annular struts may be in a contracted position about the elongated guide, and each of the bent struts may be longitudinally elongated. When the expandable framework moves from the collapsed configuration to the expanded configuration, each of the annular struts may move to a radially expanded position about the elongate guide, the central strut may maintain essentially the same shape as when the expandable framework is in the collapsed configuration, and each of the bent struts may move to a radially expanded shape.

[0008] When the expandable framework is in the expanded configuration, the groups of bent struts may be positioned to define a circumference of the expandable framework. The circumference defined by the groups of bent struts may vary from one group of bent struts to another such that one group of bent struts may define a smaller circumference than another circumference defined by a different group of bent struts. The expandable frame may include several groups of bent struts, including a distal group near a distal end of the frame, a proximal group near a proximal end of the frame, and one or more intermediate groups between the proximal and distal groups. The distal and proximal groups may each define a circumference greater than any circumference defined by the intermediate groups of bent struts. Alternatively, each of the groups of bent struts may define a circumference substantially equal to the circumference defined by each of the other groups of bent struts.

[0009] When the expandable framework is in the expanded configuration, the groups of central struts may be positioned so that they each define an inner circumference of the expandable framework. At least one of the circumferences defined by at least one of the groups of central struts may be smaller than at least one of the circumferences defined by at least one of the groups of bent struts. The groups of central struts having the smaller circumferences may be positioned between the groups of bent struts having the larger circumferences such that the expandable framework has a variable circumference along some or all of its length that transitions between the larger circumference defined by the bent struts and the smaller circumference defined by the central struts.

[0010] When the expandable framework is in the expanded configuration, the expandable body may have a first circumference defined by the first group of bent struts and a second circumference defined by the first group of central struts positioned adjacent to the first group of bent struts. The second circumference may be of a smaller dimension than the first circumference. The second group of bent struts may be positioned adjacent to the first group of central struts to define a third circumference. The second group of central struts may be positioned adjacent to the second group of bent struts to define a fourth circumference. The fourth circumference may be approximately equal to the second circumference. The first circumference may be of a dimension greater than about twice the second circumference. The third circumference may be approximately equal to the first circumference. Alternatively, the third circumference may be smaller than the first circumference and larger than both the second circumference and the fourth circumference.

[0011] The endovascular treatment device may further include radiopaque markers secured to the bend struts by threads on the bend struts. The radiopaque markers may be positioned on the groups of bend struts so as to define respective corresponding circumferences of the respective groups of bend struts.

[0012] The expandable framework may have a proximal end and a distal end, the proximal end may be fixedly attached to the elongate guide, and the distal end may be slidably moveable over the elongate guide.

[0013] Exemplary clot capture devices can be moved from a delivery configuration to a deployed configuration, in which the clot capture device can be sized to traverse through a lumen of a catheter, and in which the clot capture device can be sized to extend radially within a lumen of a blood vessel.

[0014] The clot capture device may include annular struts, central struts, and bent struts. At least some of the annular struts may be joined to two adjacent annular struts, one distally adjacent and the other proximally adjacent. The annular struts may be joined to one of the adjacent annular struts by one or more central struts and to the other adjacent annular strut by a group of one or more bent struts. When the clot capture device is in the delivery configuration, the annular struts may have a contracted circumference and the bent struts may have a longitudinally elongated shape. When the clot capture device moves to the deployed configuration, the annular struts may expand to an expanded circumference, the bent struts may expand to a radially expanded shape, and the central struts may maintain essentially the same shape as when the clot capture device is in the delivery configuration.

[0015] When the clot capture device is in the deployed configuration, each group of bent struts may define a respective corresponding circumference that is greater in dimension than a respective corresponding expanded circumference of the annular strut, or in other words, the expanded circumference of each group of annular struts may be less in dimension than the respective circumferences defined by the bent struts of the expanded group.

[0016] When the clot capture device is in the deployed configuration, the device may include two groups of bent struts each defining a respective corresponding circumference approximately equal to one another. The device may further include a third group of bent struts having a circumference smaller than the respective corresponding circumferences defined by the other two groups. The third group may be positioned between the other two groups, distal to one group and proximal to the other group.

[0017] When the clot capture device is in the delivery configuration, the annular struts connected by the groups of bent struts may be positioned a fixed distance apart. This distance between the annular struts may decrease as the clot capture device moves from the delivery configuration to the deployed configuration. When the clot capture device is in the delivery configuration, the annular struts connected by the central strut may be positioned a fixed distance apart. This distance may remain approximately equal as the clot capture device moves from the delivery configuration to the deployed configuration.

[0018] The clot capture device may include radiopaque markers attached to some or all of the bent struts. The radiopaque markers may provide an indication of the collapsed circumference of the clot capture device when the clot capture device is in the delivery configuration. The radiopaque markers may provide an indication of the expanded circumference of the clot capture device when the clot capture device is in the deployed configuration.

[0019] Some or all of the bend struts may be threaded. Radiopaque markers may be secured to the bend struts by the threads.

[0020] The clot capture device may have an expandable frame constructed from annular struts, central struts, and bent struts. The clot capture device may also include a guidewire extending through a central axis of the expandable frame. The guidewire may be affixed to a proximal end of the expandable frame. The distal end of the expandable frame may be free to move over the guidewire as the frame expands and / or contracts.

[0021] Exemplary methods may include one or more of the following steps, which may be performed in various orders, combinations, and with additional steps not enumerated herein: The expandable frame may be positioned to surround the guidewire. The frame may be attached to the guidewire at an attachment site near a proximal end of the frame. The frame may be collapsed about the guidewire in a delivery configuration dimensioned to traverse a lumen of the catheter. The frame may be expanded from the delivery configuration to a deployed configuration. The attachment of the frame to the guidewire at the attachment site may be maintained as the frame expands from the delivery configuration to the deployed configuration. At least a portion of the frame may slide over the guidewire as the frame expands from the delivery configuration to the deployed configuration.

[0022] The radiopaque markers may be positioned to define a larger circumference within the variable circumference when the frame is in the deployed configuration.

[0023] In the deployed configuration, the frame may be shaped to have a measurable length from its distal end to its proximal end and a variable circumference over at least a portion of its length, varying from a first circumference to a second circumference that is less than half the first circumference, to a third circumference that is greater than the second circumference, and back to the second circumference again.

[0024] The frame may be formed from annular struts, longitudinal struts, and bendable struts. Each annular strut may be positioned to surround a guidewire. The annular struts may be spaced apart along the length of the frame such that, except for the annular struts at the proximal and distal ends of the frame, each annular strut may have two adjacent annular struts, one on each side. Each annular strut may be connected to one adjacent portion by a bendable strut. Each annular strut may be connected to the other adjacent portion by a longitudinal strut. When the frame is expanded from the delivery configuration to the deployed configuration, each annular strut may extend radially away from the guidewire, the shape of each longitudinal strut may remain essentially constant, and each bendable strut may extend radially away from the guidewire.

[0025] The radiopaque markers may be positioned to provide a circumferential indication around the group of bendable struts when the frame is in the deployed configuration.

[0026] At least a portion of the frame may be expanded within the clot.At least a portion of the clot may be captured within the frame. [Brief description of the drawings]

[0027] The above and further aspects of the present invention will be further discussed with reference to the following description in conjunction with the accompanying drawings, in which like numerals indicate like structural elements and features in the various drawings. The drawings are not necessarily to scale, emphasis instead being placed on illustrating the principles of the invention. The figures depict one or more implementations of an apparatus of the present invention, by way of example only and not by way of limitation. [Figure 1] 1 is a perspective view of an exemplary intravascular treatment device in an expanded configuration, in accordance with aspects of the present invention. [Diagram 2] 2 is a perspective view of the exemplary intravascular treatment device shown in FIG. 1 in a collapsed or delivery configuration. [Figure 3A] 2 is a side view of the expanded exemplary endovascular treatment device shown in FIG. 1. [Figure 3B] 3B is a cross-sectional view of an exemplary intravascular treatment device as shown in FIG. 3A. [Figure 3C] 3B is a cross-sectional view of an exemplary intravascular treatment device as shown in FIG. 3A. [Figure 4A] FIG. 3 is a side view of the folded exemplary intravascular treatment device shown in FIG. 2. [Figure 4B] 4B is a cross-sectional view of an exemplary intravascular treatment device as shown in FIG. 4A. [Figure 4C] 4B is a cross-sectional view of an exemplary intravascular treatment device as shown in FIG. 4A. [Figure 5A] 1 is a side view of an exemplary endovascular treatment device having an alternative expanded or deployed configuration, in accordance with aspects of the present invention. [Figure 5B] 5B is a cross-sectional view of an exemplary intravascular treatment device as shown in FIG. 5A. [Figure 5C] 5B is a cross-sectional view of an exemplary intravascular treatment device as shown in FIG. 5A. [Figure 5D] 5B is a cross-sectional view of an exemplary intravascular treatment device as shown in FIG. 5A. [Figure 6] 1 is a perspective view of an exemplary stent in an expanded configuration, in accordance with an aspect of the present invention. [Figure 7A] 1A-1D are diagrams of a radiopaque marker assembly and a threaded bent strut according to an embodiment of the present invention. [Figure 7B] 1A-1D are diagrams of a radiopaque marker assembly and a threaded bent strut according to an embodiment of the present invention. [Figure 7C] 1A-1D are diagrams of a radiopaque marker assembly and a threaded bent strut according to an embodiment of the present invention. [Figure 8] 1 is a diagram of an exemplary endovascular treatment device being delivered through the vasculature to a blood clot, in accordance with an aspect of the present invention. [Figure 9] 9 is a diagram of the endovascular treatment device shown in FIG. 8 approaching a blood clot. [Figure 10]FIG. 10 is a diagram of the intravascular treatment device shown in FIGS. 8-9 expanded within a blood clot. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] Visualization of nickel titanium (nitinol) stents or clot retrievers during clinical use can be difficult due to the poor radiopacity of nitinol. Various exemplary endovascular treatment devices are described herein to improve visualization of clot retrievers and stents. In general, the device may have a collapsible frame 110 with radiopaque markers 150 attached and a delivery system 200 positioned to deliver the frame to the treatment site. A system of radiopaque markers attached to the body of a self-expanding nickel titanium (nitinol) stent or clot retriever may allow visualization under fluoroscopy of the outer surface of the device. The radiopaque markers may allow the user to determine the conformity of the outer body of the device to the vessel wall, as in the case of a stent. In the case of a clot retriever, the markers may allow the user to identify the location of the clot on the body of the device, aiding in the process of retrieving the clot from the vessel.

[0029] FIG. 1 is a perspective view of an exemplary intravascular treatment device in an expanded configuration. Frame 110 may be collapsed to fit through a lumen of a catheter and expanded within a blood vessel as part of an intravascular procedure. Frame 110 may include a shape memory material such that the frame has a predetermined expanded shape as shown in FIG. 1 and a deformed collapsed shape as shown in FIG. 2. FIG. 3A is a side view of intravascular treatment device 100 when expanded, and FIGS. 3B and 3C are cross-sectional views of the expanded intravascular treatment device 100 as shown in FIG. 3A. FIG. 4A is a side view of intravascular treatment device 100 when collapsed, and FIGS. 4B and 4C are cross-sectional views of the collapsed intravascular treatment device 100 as shown in FIG. 4A.

[0030] When the device 100 is deployed during a procedure, the frame 110 may expand from a collapsed configuration, as shown in FIGS. 2 and 4A-4C, to an expanded configuration, or toward a predetermined shape, as shown in FIGS. 1 and 3A-3C. The frame 110 may be prevented from fully expanding to the predetermined shape by the geometry of the vessel in which the frame 110 is deployed. In some applications, the frame 110 may advantageously expand through an obstruction, such as a clot. In other applications, the frame 110 may be prevented from fully expanding to the predetermined shape by a clot, plaque, or obstruction. Thus, the frame 110 may expand to a deployed configuration when expanded within a vessel based on the predetermined shape of the expanded configuration, and possibly also shaped by the treatment site in which the frame 110 is deployed.

[0031] 1-4C collectively, the expandable frame 110 of the device may include bent struts 120, circular struts 160, and a straight central strut 140. The device 100 may include a delivery system 200 including a guidewire 210. A proximal end 112 of the frame 110 may be secured to the guidewire 210, and a distal end 114 of the frame 110 may be free to slide over the guidewire 210. The proximal end 112 of the frame 110 may include an attachment mechanism 172, such as an adhesive, a weld, or other known attachment style, to secure the frame 110 to the guidewire 210. The distal end 114 of the frame may include a sliding collar 174 positioned to slide longitudinally along the guidewire 210.

[0032] 1 and 3A-3C, in an expanded or deployed configuration, circular struts 160 may be positioned along the length 138 of frame 110. Circular struts 160 may surround guidewire 110. Guidewire 110 may extend through frame 110 along a central axis of the frame and may pass through each circular strut 160 at or near the center of the circle created by each circular strut 160. Each circular strut 160 may be parallel to one another and oriented in a plane perpendicular to the central axis of frame 110 and guidewire 210.

[0033] Each circular strut 160 may have two adjacent circular struts 160, one distal adjacent strut and one proximal adjacent strut, except for the distal-most circular strut 160 and the proximal-most circular strut 160. The distal-most circular strut 160 may only have a proximal adjacent strut. The proximal-most circular strut 160 may only have a distal adjacent strut. The frame 110 may include longitudinally extending struts 140, 120 connecting each circular strut 160 to its adjacent struts.

[0034] In the expanded or deployed configuration, the longitudinally extending struts 140, 120 may include straight struts 140 that are essentially straight connectors extending between adjacent circular struts 160 and bent struts 120 that extend both radially outward and longitudinally between adjacent circular struts 160. Each circular strut 160 may be connected to one of its adjacent struts by a straight strut 140 and to another of its adjacent struts by a bent strut 120.

[0035] Groups of straight struts 140 may extend between adjacent circular struts 160 to define an inner circumference 134 of the frame 110 when the frame 110 is in the deployed or expanded configuration. Adjacent circular struts 160 may each have a circumference that is approximately equal to one another. The inner circumference 134 defined by groups of straight struts 140 extending between adjacent circular struts 160 may be equal to or approximately equal to the circumference of the circular struts 160. As shown in FIG. 1, each corresponding group of straight struts 140 may define an inner circumference 134 that is approximately equal to the inner circumference 134 defined by all of the other groups of straight struts 140.

[0036] Adjacent circular struts 160 connected by a group of straight struts 140 may be separated by a distance 162 when the frame 110 is in the expanded or deployed configuration. The distance 162 may be approximately equal to the length of each substantially straight strut 140 in the group of straight struts 140 that connects adjacent circular struts 160.

[0037] Each group of straight struts 140 may include four straight struts 140 positioned equidistantly around the inner circumference 134. It is contemplated that as few as three straight struts 140 and as many as six straight struts 140 may form a group of straight struts 140. Fewer straight struts 140 in a group may provide the frame 110 with more flexibility and larger openings to facilitate extending through the clot. More straight struts 140 in a group may provide more structural integrity and smaller openings to increase containment or grip on the clot.

[0038] The frame 110 may be constructed such that all of the groups of straight struts 140 include an equal number of straight struts 140. Alternatively, the frame 110 may be constructed such that groups of straight struts 140 have differing numbers of straight struts 140 to vary the flexibility and opening size within the frame 110 along the length 138 of the frame 110. For example, it may be advantageous to have fewer groups of straight struts 140 near the middle of the length 138 so that the frame 110 can more easily extend through the clot and more groups of straight struts 140 near the distal end of the frame 110 to more effectively contain the clot as it is pulled proximally through the vasculature by the device 100.

[0039] When frame 110 is in the deployed configuration, each bent strut 120 may extend radially outward from circular strut 160 and bend approximately 90° to extend substantially longitudinally parallel to guidewire 210, or the central axis of frame 110 may bend approximately 90° again and extend radially inward. Bent struts 120 may be "U" shaped, with the legs of the "U" oriented radially away from the centerline of frame 110 or guidewire 210, and the recess of the "U" located furthest away from the frame centerline or guidewire 210.

[0040] On some or all of the bend struts 120, the radiopaque markers may be attached centrally along the bend struts 120. When the frame 110 is in the expanded or deployed configuration, the radiopaque markers may be positioned in "U" shaped recesses on some or all of the bend struts 120. In other words, the radiopaque markers 150 may be attached to some or all of the bend struts 120, at a portion of each bend strut 120 that extends longitudinally and substantially parallel to a central axis of the guidewire 210 or frame 110.

[0041] When the frame 110 is in the deployed configuration, each group of bend struts 120 may extend to define a respective circumference 130 of the frame 110. A plurality of bend struts 120 within a group of bend struts may include a radiopaque marker 150 attached thereto, such that the radiopaque marker 150 indicates the circumference 130 of the group of bend struts.

[0042] Some or all of the bend struts 120 may be threaded, and the radiopaque markers 150 may be molded to fit over the threads on the bend struts 120 .

[0043] The frame 110 may have alternating groups of bent struts 120 and groups of straight struts 140 along a length 138 of the frame 110. The groups of bent struts 120 may each define a corresponding outer perimeter 130 that is greater than a corresponding inner perimeter 134 defined by each group of straight struts 134. The frame 110 may thereby have a variable circumference along the length 138 of the frame 110 that alternates between the larger outer perimeter 130 defined by the groups of bent struts 120 and the smaller inner perimeter 134 defined by the groups of straight struts 140.

[0044] Each group of bent struts 120 may include four bent struts 120 positioned equidistantly around the circumference 130. It is contemplated that as few as three bent struts 120 and as many as six bent struts 120 may form a group of bent struts 120. Fewer bent struts 120 in a group may provide the frame 110 with more flexibility to facilitate extending through the clot. More bent struts 120 in a group may provide greater structural integrity and smaller openings to increase containment or grip on the clot.

[0045] The frame 110 may be constructed such that all of the groups of bent struts 120 include an equal number of bent struts 120. Alternatively, the frame 110 may be constructed such that groups of bent struts 120 have different numbers of bent struts 120 along the length 138 of the frame 110 to vary the flexibility and opening size in the frame 110. For example, it may be advantageous to have fewer groups of bent struts near the middle of the length 138 so that the frame 110 can more easily extend through the clot that is near the distal end of the frame 110 and through the more numerous groups of bent struts 120 to more effectively contain the clot as it is pulled proximally through the vasculature by the device 100.

[0046] The bent struts 120 may be longitudinally aligned with the central struts 140 to form a continuous longitudinal extension along the majority of the length 138 of the frame 110. Figures 1-4C show a frame 110 having four such continuous longitudinal extensions, each including four bent struts 120 and three straight struts 140. The bent struts 120 and straight struts 140 may be positioned in an alternating manner as illustrated and separated by connections to circular struts 160.

[0047] The frame 110 may also include proximal end struts 182 and distal end struts 184. The proximal end struts 182 may be shaped to connect the frame 110 to the proximal attachment node 172. The distal end struts 184 may be shaped to connect the frame 110 to the distal sliding attachment 174. The proximal end struts 182 and distal end struts 184 may be longitudinally aligned with the bent struts 120 and the straight struts 140, respectively. The continuous longitudinal extension may include the proximal end struts 182 at the proximal end 112 of the frame 110 and the distal end struts 184 at the distal end 114 of the frame 110. The continuous longitudinal extension may thereby extend all or a majority of the length 138, 139 of the frame 110 in the expanded or collapsed configuration.

[0048] In the delivery / collapsed configuration, the frame 110 may be collapsed to fit through a lumen of a catheter. In the collapsed configuration, the frame 110 may have a longer length 139 compared to the length 138 of the frame 110 in the expanded configuration.

[0049] The circular struts 160 may be folded into a folded circumference 136 that is smaller than the circumference 134 of the circular struts 160 in the expanded configuration. Adjacent circular struts 160 connected by straight struts 140 may be separated by a distance 161 when the frame 110 is in the folded configuration that is approximately equal to the distance 162 between the annular struts 160 when the frame 110 is in the expanded configuration. The bent struts 120 may be elongated when the frame 110 is in the folded configuration. Adjacent circular struts 160 connected by bent struts 120 may be separated by a distance 163 when the frame 110 is in the folded configuration that is greater than the length 164 between adjacent circular struts 160 in the expanded or deployed configuration. When the frame 110 is in the collapsed configuration, each group of bend struts 120 may define a circumference 132 that is smaller than the circumference 130 defined by each corresponding group of bend struts 120 in the expanded configuration.

[0050] Comparing the length 138 of the frame 110 in the expanded configuration to the length 139 of the frame 110 in the collapsed configuration, the length 139 in the collapsed configuration may be increased primarily due to the longitudinal extension of the bending struts 120 .

[0051] Frame 110 may have exemplary predetermined shapes as shown in Figures 1 and 3A-3C, and deformed shapes as shown in Figures 2 and 4A-4C. Frame 110 may be heat set into a predetermined shape and collapsed into a deformed shape for delivery through a catheter. Frame 110 may be deformed by extending bent struts 120 distally in a substantially straight line and crimping round struts 160.

[0052] The delivery system 200 may include a radiopaque coil 250 at its distal end. As shown in Figures 2 and 4A-4C, the length 139 of the frame 110 may extend along the guidewire 210 between the proximal attachment node 172 and the radiopaque coil 250. Thus, the delivery system 200 may be dimensioned with the distance between the proximal attachment node 172 and the radiopaque coil sufficient to allow the frame 110 to extend such that the bent struts 120 can be collapsed sufficiently to fit within the lumen of a catheter.

[0053] As device 100 is deployed, it may move from a deformed configuration, as shown in Figures 2 and 4A-4C, toward a predetermined shape, as shown in Figures 1 and 3A-3C. Free distal end 114 of frame 110 may slide proximally over guidewire 210 as bent struts 120 move from a substantially straight state when frame 110 is in a collapsed configuration to a "U" shape when frame 110 is in an expanded configuration. Circular struts 160 may expand radially when moving toward the predetermined shape.

[0054] Figures 5A-5D are diagrams of an exemplary endovascular treatment device 100a having alternative expanded or deployed configurations. Like reference numbers indicate similar or identical elements common between the device 100 shown in Figures 1-4C and the device 100a shown in Figures 5A-5D. Figure 5A is a side view of device 100a, and Figures 5B-5D are cross-sectional views of device 100a as shown in Figure 5A.

[0055] Comparing the exemplary device 100 shown in Figures 1-4C to the exemplary device 100a shown in Figures 5A-5D, the expandable frame 110a of the device 100a in Figures 5A-5D includes groups of bent struts 120a, 120b that define different circumferences 130a, 130b, while the groups of bent struts 120 shown in Figures 1-4C define approximately equal circumferences 130. The device 100a shown in Figures 5A-5D may include a first group of bent struts 120a that define a first circumference 130a and a second group of bent struts 120b that define a second circumference 130b that is smaller than the first circumference 130a. The group of bent struts 120b that define the smaller circumference 130b may be centrally located along the length 138 of the frame 110a. Each group of bent struts 120b defining a smaller circumference 130b may be positioned between two groups of bent struts 120a defining a corresponding larger circumference 130a.

[0056] It may be advantageous to centrally position one or more groups of bent struts 120b that each correspondingly define a smaller circumference 130b along the length 138 of the frame 110a, such that the bent struts 120b in those groups do not compress as far longitudinally when the frame 110a is collapsed, or extend as far radially when the frame 110a is expanded. This may result in the frame 110a being less long when compressed in the delivery configuration, as compared to a frame 110 having evenly sized bent struts 120 as shown in FIG.

[0057] The smaller central bending struts 120b may define smaller openings in the frame 110a that may provide a better grip on the clot. The larger bending struts 120a at the distal and proximal ends 112, 114 of the frame 110a may act to contain the clot longitudinally.

[0058] The device 100a shown in Figures 5A-5D may be stretched and compressed in a manner similar to that described in connection with the device 100 shown in Figure 2. When expanded as shown in Figure 5A, adjacent circular struts 160 connected by a first group of bent struts 120a of a greater circumference may be separated by a first distance 164a, and adjacent circular struts 160 connected by a second group of bent struts 120b of a smaller circumference may be separated by a second distance 164b. The first distance 164a and the second distance 164b may be approximately equal to one another. When the frame 110a is collapsed for delivery through a catheter, the bend struts 120a, 120b may extend longitudinally such that adjacent circular struts 160 connected by a first group of bend struts 120a are separated by a third distance that is greater than the first distance, and adjacent circular struts 160 connected by a second group of bend struts 120b are separated by a fourth distance that is greater than the second distance and less than the third distance. In other words, when the frame 110a is in the delivery configuration, the first group of bend struts 120a may be longer than the second group of bend struts 120b, and both groups of bend struts 120a, 120b may be longitudinally longer than when in the expanded configuration.

[0059] The delivery system 200 may be dimensioned such that the frame 110a has sufficient space to expand longitudinally between the proximal attachment node 172 and the radiopaque coil 250 so that the frame 110a can be collapsed to fit within a microcatheter.

[0060] Figure 6 is an illustration of a stent 100c having an expandable frame 110c having a structure similar to the frame 100 shown in Figures 1-4C. Like reference numbers indicate similar or identical elements that are common between the device 100 shown in Figures 1-4C and the stent 100c shown in Figure 6.

[0061] Comparing the exemplary device 100 shown in Figures 1-4C to the stent 100c shown in Figure 6, the expandable frame 110c of the stent 100c of Figure 6 does not need to be attached to a guidewire 210, and thus the frame 110c is shown lacking the delivery system 200, attachment mechanism 172, proximal connecting struts 182, distal sliding collar 174, and distal connecting struts 184. The proximal and distal ends 112c, 114c of the frame 110c may be terminated by circular struts 160 as shown, or by other expandable and / or anchoring structures as will be recognized and understood by those skilled in the art. The struts 100c may have a length 138c in the expanded configuration, which can be measured from the proximal end 112c of the frame 110c to the distal end 114c of the frame.

[0062] Several delivery systems are known for delivering stents to blood vessels, and such delivery systems will not be described in detail herein. Stent 100c may be delivered by a delivery system, as will be recognized and understood by those skilled in the art. Stent 100c may be collapsed for delivery via a catheter similar to that shown in FIG.

[0063] 7A-7C are diagrams of a radiopaque marker assembly 150 and a threaded bend strut 120. Some or all of the bend struts 120, 120a, 120b in the exemplary devices 100, 100a, 100c presented herein may include threads 121 as shown in FIGS.

[0064] The radiopaque marker 150 may have a helical coil 152 and end attachments 154, 156. Each helical coil 152 may be wrapped onto the threads 121 of a respective bent strut 120, as shown in FIG. 7A. The bent strut 120 may be bent to have a first strut leg 124, a second strut leg 126, and a threaded portion 122 extending between the first strut leg 124 and the second strut leg 126. The bend may separate the first strut leg 124 from the threaded portion 122 of the strut 120. The bend may be shaped to facilitate winding the helical coil 152 of the radiopaque marker 150 onto the threads 121, as shown in FIG. 7A.

[0065] Once the helical coil 152 is positioned as shown in Figure 7B, the ends of the coil 152 may be secured to the struts 120 using end attachments 154, 156. The end attachments 154, 156 may be welds, adhesives, or other known attachments.

[0066] 8-10 show the intravascular treatment device 100 capturing the clot C. Fig. 8 shows the device 100 collapsed within a microcatheter and being delivered through a blood vessel towards the clot C. Fig. 9 shows the microcatheter and device 100 passing through the clot C. Fig. 10 shows the microcatheter retracted within the clot C and the device 100 expanded.

[0067] The descriptions contained herein are examples of embodiments of the invention and are not intended to limit the scope of the invention in any way. As described herein, the invention contemplates many variations and modifications of the endovascular treatment device, including alternative uses of endovascular treatment, alternative materials, alternative geometries, alternative numbers of components, alternative delivery mechanisms, etc. These modifications will be apparent to those skilled in the art to which the invention pertains and are intended to be within the scope of the following claims.

[0068] [Embodiment] (1) An intravascular treatment device, comprising: A long guide and an expandable framework movable from a collapsed configuration dimensioned to traverse a lumen of a catheter to an expanded configuration dimensioned to extend into a lumen of a blood vessel, the expandable framework comprising: a plurality of annular struts, each annular strut surrounding the elongate guide, each annular strut movable from a contracted position about the elongate guide when the expandable framework is in the collapsed configuration to a radially expanded position about the elongate guide when the expandable framework is in the expanded configuration; a plurality of central struts, each central strut joining two adjacent annular struts of the plurality of annular struts such that each annular strut is joined to only a first adjacent annular strut by one or more central struts of the plurality of central struts, each central strut having a shape when the expandable framework is in the collapsed configuration that is essentially the same as a shape of the central strut when the expandable framework is in the expanded configuration; and an expandable framework including a plurality of bent struts, each bent strut joining two adjacent annular struts of the plurality of bent struts such that each annular strut is joined by one or more bent struts of the plurality of bent struts only to a second adjacent annular strut opposite the first adjacent annular strut, each of the plurality of bent struts being movable from a longitudinally elongated shape when the expandable framework is in the collapsed configuration to a radially expanded shape when the expandable framework is in the expanded configuration. (2) when the extensible framework is in the extended configuration, a first group of bent struts of the plurality of bent struts positioned to define a first circumference of the expandable framework; The device of embodiment 1, wherein a first group of central struts of the plurality of central struts are positioned to define a second circumference of the expandable framework that is a smaller dimension than the first circumference. (3) when the extensible framework is in the extended configuration, a second group of bent struts of the plurality of bent struts are positioned adjacent to a central strut of the first group and positioned to define a third circumference of the expandable framework approximately equal to the first circumference; The device of embodiment 2, wherein a second group of central struts among the plurality of central struts are positioned adjacent to the second group of bent struts and positioned to define a fourth circumference of the expandable framework approximately equal to the second circumference. (4) The device of embodiment 3, wherein the first circumference is more than twice the dimension of the second circumference. (5) the expandable framework further comprises a proximal end and a distal end; the proximal end is secured to the elongate guide; 2. The device of embodiment 1, wherein the distal end is slidably movable across the elongate guide.

[0069] (6) further comprising a plurality of radiopaque markers; At least some of the bending struts each include a thread; 2. The device of embodiment 1, wherein each of the radiopaque markers among the plurality of radiopaque markers is fixed to each of the at least a portion of the bent struts by the threads. (7) further comprising a plurality of radiopaque markers; a first group of the plurality of radiopaque markers positioned on the first group of bent struts to define the first circumference; The device of embodiment 3, wherein a second group of the plurality of radiopaque markers are positioned on the second group of bent struts to define the third circumference. (8) The device of embodiment 1, wherein in the expanded configuration, the expandable framework has a distal end, a proximal end, a length measurable from the distal end to the proximal end, and a variable circumference along at least a portion of the length of the framework, transitioning from a first circumference to a second circumference of a dimension smaller than the first circumference, from the second circumference to a third circumference of a dimension greater than the second circumference and equal to or smaller than the first circumference, and from the third circumference back to the second circumference. (9) In the expanded configuration, the third circumference is smaller than the first circumference; The device of embodiment 8, wherein in the expanded configuration, the first circumference is defined by a first group of bent struts among the plurality of bent struts, the second circumference is defined by two adjacent radially expanded annular struts and one or more central struts joining the two adjacent radially expanded annular struts, and the third circumference is defined by the second group of bent struts. (10) An expandable clot capture device movable from a delivery configuration dimensioned to traverse a lumen of a catheter to a deployed configuration dimensioned to extend into a lumen of a blood vessel, the device comprising: a plurality of annular struts, each annular strut movable from a contracted circumference when the clot capture device is in the delivery configuration to an expanded circumference when the clot capture device is in the deployed configuration; a plurality of central struts, each central strut comprising a shape when the clot capture device is in the delivery configuration that is essentially the same as a shape of the central strut when the clot capture device is in the deployed configuration; a plurality of bent struts, each of the plurality of bent struts movable from a longitudinally elongated shape when the device is in the delivery configuration to a radially expanded shape when the clot capture device is in the deployed configuration; at least some of the plurality of annular struts are each joined to a first adjacent annular strut and a second adjacent annular strut opposite the first adjacent annular strut; each of the at least some of the plurality of annular struts is joined to an associated first adjacent annular strut by one or more central struts of the plurality of central struts; An expandable clot capture device, wherein each of the at least some of the plurality of annular struts is joined to a second adjacent annular strut by a group of one or more bent struts of the plurality of bent struts.

[0070] (11) When the clot capture device is in the deployed configuration, each group of the one or more bent struts defines a respective circumference; An expandable clot capture device as described in embodiment 10, wherein when the clot capture device is in the deployed configuration, the expanded circumference of each annular strut is smaller than the corresponding circumference of each group of the one or more bent struts. (12) The expandable clot capture device of embodiment 11, wherein when the clot capture device is in the deployed configuration, a first group of one or more bent struts defines a first circumference, a second group of one or more bent struts defines a second circumference approximately equal to the first circumference, and a third group of one or more bent struts positioned distal to the first group and proximal to the second group has a third circumference that is a smaller dimension than the first and second circumferences and a larger dimension than the expanded circumference of each annular strut. (13) each of the at least some of the plurality of annular struts is separated from a respective first adjacent annular strut by a first distance when the clot capture device is in the delivery configuration and by a second distance when the clot capture device is in the deployed configuration, the first distance being approximately equal to the second distance; An expandable clot capture device as described in embodiment 10, wherein each of at least a portion of the plurality of annular struts is separated from a respective second adjacent annular strut by a third distance when the clot capture device is in the delivery configuration and by a fourth distance when the clot capture device is in the deployed configuration, the third distance being greater than the fourth distance. (14) further comprising a plurality of radiopaque markers, wherein at least a portion of the bend struts comprises a radiopaque marker of the plurality of radiopaque markers attached to the at least a portion of the bend struts; An expandable clot capture device as described in embodiment 11, wherein the plurality of radiopaque markers provide an indication of a folded circumference of the clot capture device when the clot capture device is in the delivery configuration and an indication of an expanded circumference of the clot capture device when the clot capture device is in the deployed configuration. (15) The expandable clot capture device of embodiment 14, wherein each of the at least a portion of the bent struts comprises a screw thread, and each of the radiopaque markers of the plurality of radiopaque markers is secured to each of the at least a portion of the bent struts by the screw thread.

[0071] (16) The blood clot capture device comprises: an expandable frame comprising the plurality of annular struts, the plurality of central struts, and the plurality of bent struts; The expandable clot capture device of embodiment 10, further comprising a guidewire extending through a central axis of the expandable frame and secured to the expandable frame at a single node proximate the proximal end of the expandable frame. (17) A method comprising the steps of: Positioning an expandable frame around a guidewire; attaching the frame to the guidewire at an attachment site proximate a proximal end of the frame; collapsing the frame about the guidewire such that the frame is in a delivery configuration dimensioned to traverse a lumen of a catheter; Expanding the frame from the delivery configuration to a deployed configuration; maintaining the attachment of the frame to the guidewire at the attachment site as the frame expands from the delivery configuration to the deployed configuration; sliding at least a portion of the frame over the guidewire as the frame expands from the delivery configuration to the deployed configuration; and shaping the frame in the expanded configuration to have a measurable length from the distal end to the proximal end and a variable circumference along at least a portion of the length of the frame, transitioning from a first circumference to a second circumference having a dimension less than half of the first circumference, to a third circumference having a dimension greater than the second circumference and less than or equal to the first circumference, and from the third circumference back to the second circumference. (18) forming the frame from a plurality of annular struts, a plurality of longitudinal struts, and a plurality of bendable struts; Positioning each annular strut so as to surround the guidewire; spacing the plurality of annular struts along a length of the frame such that each annular strut has a first adjacent neighboring annular strut and a second adjacent neighboring annular strut; connecting each annular strut to a first adjacent neighboring annular strut of the each annular strut by one or more longitudinal struts of the plurality of longitudinal struts; connecting each annular strut to a second adjacent neighboring annular strut of the each annular strut by one or more bendable struts of the plurality of bendable struts; The step of expanding the frame from the delivery configuration to the deployed configuration comprises: expanding each annular strut of the plurality of annular struts radially away from the guidewire as the frame expands from the delivery configuration to the deployed configuration; maintaining an essentially constant shape of each longitudinal strut of the plurality of longitudinal struts as the frame expands from the delivery configuration to the deployed configuration, wherein a shape of each longitudinal strut when the frame is in the delivery configuration does not essentially change after the frame is in the deployed configuration; 18. The method of embodiment 17, further comprising extending each bendable strut of the plurality of bendable struts radially away from the guidewire as the frame expands from the delivery configuration to the deployed configuration. (19) expanding at least a portion of the frame within a clot; 18. The method of claim 17, further comprising capturing at least a portion of the clot within the frame. (20) The method of embodiment 17, further comprising positioning a plurality of radiopaque markers to provide an indication of the first circumference and the third circumference when the frame is in the expanded configuration.

Claims

1. An intravascular treatment device, comprising: A long guide and an expandable framework movable from a collapsed configuration dimensioned to traverse a lumen of a catheter to an expanded configuration dimensioned to extend into a lumen of a blood vessel, the expandable framework comprising: a plurality of annular struts, each annular strut surrounding the elongate guide, each annular strut movable from a contracted position about the elongate guide when the expandable framework is in the collapsed configuration to a radially expanded position about the elongate guide when the expandable framework is in the expanded configuration; a plurality of central struts, each central strut joining two adjacent annular struts of the plurality of annular struts such that each annular strut is joined to only a first adjacent annular strut by one or more central struts of the plurality of central struts, each central strut having a shape when the expandable framework is in the collapsed configuration that is essentially the same as a shape of the central strut when the expandable framework is in the expanded configuration; and an expandable framework including a plurality of bent struts, each bent strut joining two adjacent annular struts of the plurality of bent struts such that each annular strut is joined by one or more bent struts of the plurality of bent struts only to a second adjacent annular strut opposite the first adjacent annular strut, each of the plurality of bent struts being movable from a longitudinally elongated shape when the expandable framework is in the collapsed configuration to a radially expanded shape when the expandable framework is in the expanded configuration.

2. When the extensible framework is in the extended configuration: a first group of bent struts of the plurality of bent struts positioned to define a first circumference of the expandable framework; 2. The intravascular treatment device of claim 1, wherein a first group of central struts of the plurality of central struts are positioned to define a second circumference of the expandable framework that is sized smaller than the first circumference.

3. When the extensible framework is in the extended configuration: a second group of bent struts of the plurality of bent struts are positioned adjacent to a central strut of the first group and positioned to define a third circumference of the expandable framework approximately equal to the first circumference; 3. The intravascular treatment device of claim 2, wherein a second group of central struts of the plurality of central struts are positioned adjacent to the second group of bent struts and positioned to define a fourth circumference of the expandable framework approximately equal to the second circumference.

4. The intravascular treatment device of claim 3 , wherein the first circumference is greater than about twice the size of the second circumference.

5. the expandable framework further comprises a proximal end and a distal end; the proximal end is secured to the elongate guide; The intravascular treatment device of claim 1 , wherein the distal end is slidably moveable over the elongate guide.

6. a plurality of radiopaque markers; At least some of the bending struts each include a thread; The intravascular treatment device of claim 1 , wherein each of the radiopaque markers of the plurality of radiopaque markers is secured to each of the at least a portion of the bent struts by the threads.

7. a plurality of radiopaque markers; a first group of the plurality of radiopaque markers positioned on the first group of bent struts to define the first circumference; The intravascular treatment device of claim 3 , wherein a second group of the plurality of radiopaque markers are positioned on the second group of bent struts to define the third circumference.

8. 2. The intravascular treatment device of claim 1, wherein in the expanded configuration, the expandable framework comprises a distal end, a proximal end, a length measurable from the distal end to the proximal end, and a variable circumference that transitions along at least a portion of the length of the expandable framework from a first circumference to a second circumference of a dimension smaller than the first circumference, from the second circumference to a third circumference of a dimension greater than the second circumference and equal to or smaller than the first circumference, and from the third circumference back to the second circumference.

9. in the expanded configuration, the third circumference is a smaller dimension than the first circumference; 9. The intravascular treatment device of claim 8, wherein in the expanded configuration, the first circumference is defined by a first group of bent struts of the plurality of bent struts, the second circumference is defined by two adjacent radially expanded annular struts and one or more central struts joining the two adjacent radially expanded annular struts, and the third circumference is defined by a second group of bent struts.

10. 1. An expandable clot capture device movable from a delivery configuration dimensioned to traverse a lumen of a catheter to a deployed configuration dimensioned to extend into a lumen of a blood vessel, the clot capture device comprising: a plurality of annular struts, each annular strut movable from a contracted circumference when the clot capture device is in the delivery configuration to an expanded circumference when the clot capture device is in the deployed configuration; a plurality of central struts, each central strut comprising a shape when the clot capture device is in the delivery configuration that is essentially the same as a shape of the central strut when the clot capture device is in the deployed configuration; a plurality of bent struts, each of the plurality of bent struts movable from a longitudinally elongated shape when the clot capture device is in the delivery configuration to a radially expanded shape when the clot capture device is in the deployed configuration; at least some of the plurality of annular struts are each joined to a first adjacent annular strut and a second adjacent annular strut opposite the first adjacent annular strut; each of the at least some of the plurality of annular struts is joined to a first adjacent annular strut by one or more central struts of the plurality of central struts; An expandable clot capture device, wherein each of the at least some of the plurality of annular struts is joined to a second adjacent annular strut by a group of one or more bent struts of the plurality of bent struts.

11. when the clot capture device is in the deployed configuration, each group of the one or more bent struts defines a respective circumference; The expandable clot capture device of claim 10 , wherein when the clot capture device is in the deployed configuration, the expanded circumference of each annular strut is dimensioned to be less than a corresponding circumference of each group of the one or more bent struts.

12. 12. The expandable clot capture device of claim 11, wherein when the clot capture device is in the deployed configuration, a first group of one or more bent struts defines a first circumference, a second group of one or more bent struts defines a second circumference approximately equal to the first circumference, and a third group of one or more bent struts positioned distal to the first group and proximal to the second group comprises a third circumference that is a smaller dimension than the first and second circumferences and a larger dimension than the expanded circumference of a respective annular strut.

13. each of the at least some of the plurality of annular struts is separated from a respective first adjacent annular strut by a first distance when the clot capture device is in the delivery configuration and by a second distance when the clot capture device is in the deployed configuration, the first distance being approximately equal to the second distance; 11. The expandable clot capture device of claim 10, wherein each of the at least some of the plurality of annular struts is separated from a respective second adjacent annular strut by a third distance when the clot capture device is in the delivery configuration and by a fourth distance when the clot capture device is in the deployed configuration, the third distance being greater than the fourth distance.

14. a plurality of radiopaque markers, at least a portion of the bend struts comprising a radiopaque marker of the plurality of radiopaque markers attached to the at least a portion of the bend struts; The expandable clot capture device of claim 11, wherein the plurality of radiopaque markers provide an indication of a collapsed circumference of the clot capture device when the clot capture device is in the delivery configuration and an indication of an expanded circumference of the clot capture device when the clot capture device is in the deployed configuration.

15. 15. The expandable clot capture device of claim 14, wherein each of the at least a portion of the bent struts comprises a screw thread, and each of the radiopaque markers of the plurality of radiopaque markers is secured to each of the at least a portion of the bent struts by the screw thread.

16. The clot capture device comprises: an expandable frame comprising the plurality of annular struts, the plurality of central struts, and the plurality of bent struts; 11. The expandable clot capture device of claim 10, further comprising a guidewire extending through a central axis of the expandable frame and anchored to the expandable frame at a single node proximate a proximal end of the expandable frame.

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