Catheter tip expandable in compressed state

Abstract

Systems and devices disclosed herein are used for a clot retrieval catheter tip that may include a support frame including a longitudinal axis, a collapsed configuration, an expanded deployed configuration, and a plurality of interconnected struts. The plurality of interconnection struts may define an axial series of expansion units and may be engaged at opposing pairs of x-connectors spaced 180 degrees about the longitudinal axis. Each opposing pair of x-connectors may be rotated 90 degrees about the longitudinal axis relative to an adjacent opposing pair of x-connectors. The support frame may also include a collapsed inner diameter in the collapsed delivery configuration and a larger expanded inner diameter in the expanded deployment configuration when the support frame is placed in a compressed state.

Description

Technical Field

[0001] The present invention generally relates to devices and methods for removing acute blockages from blood vessels during endovascular medical treatment. More specifically, the present invention relates to a retrieval catheter having an expandable tip into which one or more objects may be retrieved. Background Art

[0002] Clot retrieval aspiration catheters and devices are frequently used in mechanical thrombectomy for endovascular intervention in patients with conditions such as acute ischemic stroke (AIS), myocardial infarction (MI), and pulmonary embolism (PE). Accessing neurovascular beds using conventional techniques is particularly challenging because the target vessels are small in diameter, distal relative to the insertion site, and highly tortuous. Conventional devices are typically either too large in profile, lack the deliverability and flexibility required to navigate particularly tortuous vessels, or are ineffective in removing clots when delivered to the target site.

[0003] Many existing designs of aspiration retrieval catheters are typically limited to, for example, 6Fr or an inner diameter between approximately 0.068 inches and 0.074 inches. Larger sizes require the use of larger guides or sheaths, which in turn require the closure of larger femoral access holes. Most physicians prefer to use an 8Fr guide / 6Fr sheath combination, and few physicians feel comfortable exceeding a 9Fr guide / 7Fr sheath combination. This means that once at the target site, the clot is typically larger in size than the inner diameter of the aspiration catheter, and the clot must be compressed immediately before it can enter the catheter opening. This compression can lead to clot clumping and subsequent shearing during retrieval. Fibrin-rich, compacted clots may also aggregate in the fixed open ends of these catheters, making them more difficult to extract. This aggregation can also lead to shearing, where the softer portions of the clot break away from the more compact areas.

[0004] The small diameter and fixed tip size are also less effective at guiding the aspiration required to remove blood and thrombotic material during surgery. The fixed tip size can cause the clot to shear or split as the clot enters the tip opening. The aspiration must be strong enough so that any fragmentation that may occur due to aspiration or the use of a mechanical thrombectomy device can remain stationary so that the fragments cannot migrate and occlude the distal vessel. However, when aspiration is performed with a fixed-port catheter, a large portion of the aspiration stream terminates the vascular fluid from the proximal side of the catheter tip, where there is no clot, because the diameter of the funnel catheter is smaller than the diameter of the vessel. This significantly reduces the efficiency of aspiration, thereby reducing the success rate of clot removal.

[0005] Any catheter design that attempts to overcome these challenges with an expanded distal tip or structure needs to have the strength to extract a clot and exert a steady radial force in the expanded state. The same structure also needs to be flexible and resilient enough to withstand the severe mechanical strains imparted when navigating the tortuous vasculature in the collapsed state.

[0006] Therefore, there remains a need for improved catheter designs that attempt to overcome the above-mentioned design challenges.The present invention is designed to provide an improved retrieval catheter having an expandable tip section and methods of using such catheters that enable improved performance. Summary of the invention

[0007] The present invention aims to provide devices and methods that meet the above needs. These designs can be used for clot retrieval catheters that can remove clots from the cerebral arteries of patients with AIS, the coronary arteries of patients with MI, native or grafted vessels, and the pulmonary arteries of patients with PE, as well as other peripheral arterial and venous vessels where clots have caused obstruction.

[0008] An example of the present disclosure provides a catheter end. The catheter end may include a support frame, which includes a longitudinal axis, a collapsed configuration, an expanded deployment configuration, and a plurality of interconnected struts. A plurality of interconnected struts may define a series of expansion units in an axial direction, and may be engaged at pairs of x-connectors spaced 180 degrees apart around the longitudinal axis. Each pair of x-connectors relative to each other may be rotated 90 degrees around the longitudinal axis relative to an adjacent pair of x-connectors. The support frame may also include a collapsed inner diameter in the collapsed delivery configuration, and include a larger expanded inner diameter in the expanded deployment configuration when the support frame is placed in a compressed state.

[0009] The catheter tip may include an offset port strut at a distal end of the support frame, at least a portion of the offset port strut lying in a plane that forms an acute angle with respect to the longitudinal axis.

[0010] The support frame may include a proximal collar at the proximal end.The proximal collar may include ring members circumferentially separated by at least one seam.

[0011] The support frame can expand from a collapsed inner diameter to an expanded inner diameter when impacted by ingested clot.

[0012] The support frame can be configured to be heat set to have an expanded inner diameter that is greater than the collapsed inner diameter.

[0013] The support frame may include a shape memory alloy having an Austenite finish temperature of less than about 30 degrees Celsius.

[0014] The support frame may comprise a smaller axial length in the expanded deployed configuration than in the collapsed delivery configuration.

[0015] In the expanded deployed configuration, the support frame can include a maximum outer diameter that is smaller than an inner diameter of a target vessel at the treatment site.

[0016] When in the collapsed delivery configuration, the distal end of the support frame can include a substantially circular cross-section with a center substantially coincident with the longitudinal axis.

[0017] The interconnecting struts at the catheter tip may include a curved profile.

[0018] The axial series of expansion units may include opposing pairs of units spaced 180 degrees apart about the longitudinal axis, and each opposing pair of units may be rotated 90 degrees about the longitudinal axis relative to an adjacent opposing pair of units.

[0019] When the support frame is placed in compression, the axial series of expansion units can be shortened longitudinally.

[0020] Another example of the present disclosure provides another catheter end. The catheter end may include a support frame, which includes a longitudinal axis, a collapsed delivery configuration, an expanded deployment configuration, and an axial series of hoop ribs extending in a plane offset from the longitudinal axis. The hoop ribs may include a curved profile, a non-planar cross-section, and a distal unconnected peak. The support frame may include a mouth, which has a larger expanded inner diameter when the support frame is placed in a compressed state.

[0021] The support frame may have a larger expanded inner diameter in the expanded deployment configuration when radially impacted by ingested clot, and may have a smaller delivery inner diameter in the collapsed delivery configuration.

[0022] The support frame may include a shape memory alloy having an austenite finish temperature of less than about 30 degrees Celsius.

[0023] The support frame can be heat set to have an expanded inner diameter that is greater than the inner diameter of the collapsed delivery configuration.

[0024] The distal end of the support frame in the expanded deployed configuration can have a circular profile including a center radially offset from the longitudinal axis.

[0025] The distal end of the support frame in the collapsed delivery configuration can have a substantially circular cross-section with a center substantially coincident with the longitudinal axis.

[0026] The support frame may comprise a smaller axial length in the expanded delivery configuration than in the collapsed delivery configuration.

[0027] In the expanded deployed configuration, the support frame can include a maximum outer diameter that is smaller than an inner diameter of a target vessel at the treatment site.

[0028] When the support frame is in compression during clot ingestion, the distal unconnected peak of each of the ribs may move proximally.

[0029] At least a portion of each of the hoop ribs may lie in a plane forming an acute angle with respect to the longitudinal axis.

[0030] The support frame may include one or more connector ribs extending from a ring member connected to a proximal end of the support frame, the connector ribs diverging from the ring member in an offset plane that is substantially perpendicular to an offset plane of the hoop ribs.

[0031] At least one of the series of hoop ribs may be proximally connected to the connector rib, and at least one of the series of hoop ribs may be proximally connected to the ring member.

[0032] The support frame may include one or more support ribs extending from the ring member in a plane substantially parallel to the offset plane of the connector ribs.The support ribs may have no connection points to any of the series of hoop ribs or connector ribs.

[0033] The ring member may be configured to be press fit onto the braided section of the tubular catheter shaft.The support frame may include a proximal collar at the proximal end.The proximal collar may include ring members circumferentially separated by at least one seam.

[0034] Other aspects of the present disclosure will become apparent after viewing the following detailed description in conjunction with the accompanying drawings. Additional features or manufacturing steps and use steps may be included as will be understood and appreciated by those skilled in the relevant art. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The above aspects and other aspects of the present invention will be further discussed with reference to the following description and in conjunction with the accompanying drawings, in which similar numbers indicate similar structural elements and features in various figures. The accompanying drawings are not necessarily drawn to scale, but instead, the focus is on illustrating the principles of the present invention. The accompanying drawings depict one or more specific implementations of the apparatus of the present invention by way of example only and not by way of limitation. It is expected that those skilled in the relevant art will be able to conceive and combine elements from multiple drawings to better meet the needs of the user.

[0036] Figure 1A is a perspective view of an expandable support frame of a clot retrieval catheter in a collapsed delivery configuration according to aspects of the present invention.

[0037] Figure 1B According to various aspects of the present invention Figure 1A Side view of an expandable support frame of a clot retrieval catheter.

[0038] Figure 1CAccording to various aspects of the present invention Figure 1A and Figure 1B Top view of the expandable support frame of the clot retrieval catheter.

[0039] Figure 1D According to various aspects of the present invention Figures 1A to 1C Cross-sectional illustration of an expandable support frame of a clot retrieval catheter.

[0040] Figure 1E According to various aspects of the present invention Figures 1A to 1D Cross-sectional illustration of an expandable support frame of a clot retrieval catheter.

[0041] Figure 2A is a perspective view of an expandable support frame of a clot retrieval catheter in a collapsed delivery configuration according to aspects of the present invention.

[0042] Figure 2B According to various aspects of the present invention Figure 2A Top view of the expandable support frame of the clot retrieval catheter.

[0043] Figure 2C According to various aspects of the present invention Figure 2A and Figure 2B Side view of an expandable support frame of a clot retrieval catheter.

[0044] Figure 2D is a side view of an expandable support frame of a clot retrieval catheter in a collapsed delivery configuration according to aspects of the present invention.

[0045] Figure 3A is a perspective view of an expandable support frame of a clot retrieval catheter in a collapsed delivery configuration according to aspects of the present invention.

[0046] Figure 3B According to various aspects of the present invention Figure 3A Top view of the expandable support frame of the clot retrieval catheter.

[0047] Figure 3C According to various aspects of the present invention Figure 3A and Figure 3B Side view of an expandable support frame of a clot retrieval catheter.

[0048] Figure 3D is a side view of an expandable support frame of a clot retrieval catheter in a collapsed delivery configuration according to aspects of the present invention.

[0049] Figure 3E is a side view of an expandable support frame of a clot retrieval catheter in a collapsed delivery configuration according to aspects of the present invention.

[0050] Figure 3F is a side view of an expandable support frame of a clot retrieval catheter in a collapsed delivery configuration according to aspects of the present invention.

[0051] Figure 3G is a side view of an expandable support frame of a clot retrieval catheter in a collapsed delivery configuration according to aspects of the present invention.

[0052] Figure 4A is a perspective view of an expandable support frame of a clot retrieval catheter in a collapsed delivery configuration according to aspects of the present invention.

[0053] Figure 4B According to various aspects of the present invention Figure 4A Top view of the expandable support frame of the clot retrieval catheter.

[0054] Figure 4C According to various aspects of the present invention Figure 4A and Figure 4B Side view of an expandable support frame of a clot retrieval catheter.

[0055] Figure 5A is a perspective view of an expandable support frame of a clot retrieval catheter in a collapsed delivery configuration according to aspects of the present invention.

[0056] Figure 5B According to various aspects of the present invention Figure 5A Top view of the expandable support frame of the clot retrieval catheter.

[0057] Figure 5C According to various aspects of the present invention Figure 5A and Figure 5B Side view of an expandable support frame of a clot retrieval catheter.

[0058] Fig. 6A is a perspective view of an expandable support frame of a clot retrieval catheter in a collapsed delivery configuration according to aspects of the present invention.

[0059] Figure 6B According to various aspects of the present invention Fig. 6A Top view of the expandable support frame of the clot retrieval catheter.

[0060] Figure 6C According to various aspects of the present invention Fig. 6A and Figure 6B Side view of an expandable support frame of a clot retrieval catheter.

[0061] Figure 7 is a side view of an expandable support frame profile of a clot retrieval catheter tip according to aspects of the present invention.

[0062] Figure 8is a side view of an expandable support frame profile of a clot retrieval catheter tip according to aspects of the present invention.

[0063] Fig. 9 is a diagram of a clot retrieval catheter tip having an expandable support frame advanced through vasculature in accordance with aspects of the present invention.

[0064] FIG. 10A to FIG. 10C is an illustration of exemplary treatment steps that may be performed using a clot retrieval catheter tip expandable support frame according to aspects of the present invention.

[0065] FIG. 11A to FIG. 11C is an illustration of exemplary treatment steps that may be performed using a clot retrieval catheter tip expandable support frame according to aspects of the present invention. DETAILED DESCRIPTION

[0066] Specific examples of the present invention are now described in detail with reference to the drawings, wherein like reference numerals indicate functionally similar or identical elements. These examples address many of the drawbacks associated with conventional clot retrieval aspiration catheters, such as the inability to properly or accurately deploy to a target site and ineffective clot removal.

[0067] The designs herein (showing various configurations of catheter tip support frames) can be incorporated into an aspiration clot retrieval catheter having a membrane cover or jacket package, a proximal shaft, a large bore lumen, and a distal low shear tip (LST) that can expand to a diameter larger than the nominal diameter upon interaction with an ingested clot or a stent retriever. The designs herein can also be pre-expanded and heat set to be incorporated into a collapsible super large bore (CSB) catheter having a membrane cover and a proximal shaft to provide a catheter that collapses for delivery through a guide catheter and expands upon exiting the guide catheter to be advanced to a target vessel for aspiration of a clot.

[0068] The design of this article may have a proximal elongated body for the shaft of the catheter, and a distal end with an expanded internal frame so that the end has atraumatic properties. That is, the expanded internal frame can be easily and repeatedly collapsed for delivery, and locally expanded under the load from the clot (when used in combination with the LST catheter) or by heat setting (when used in combination with the CSB catheter), so that the catheter end can expand beyond the nominal diameter to ingest the clot. The expanded internal frame can have a proximal ring for attachment to the braided catheter shaft, and can have an offset port, thereby allowing a larger opening for clot retrieval and a reduced stiffness for easier expansion. This management of clots during ingestion can significantly reduce the shearing of clots. The design of the catheter can have enough flexibility to navigate the highly tortuous areas of the anatomical structure, and when displaced in the blood vessel, its shape can be restored to maintain the inner diameter of the lumen.

[0069] This innovation of utilizing the clot itself to expand the tip segment as needed allows for greatly improved clot handling and reduced shearing compared to conventional designs. The nominal unexpanded outer diameter maximizes distal access to the same distance as a standard fixed opening catheter. Once a clot is subsequently ingested, the stiffer fibrin-rich portion of the clot accommodated by additional radial expansion can gradually compress the clot, resulting in significantly less clot shearing compared to catheters lacking this capability. Furthermore, the compliant nature of the tip allows it to be atraumatically advanced through calcifications without dislodging plaque material.

[0070] Access to the various vessels within the vascular system (whether coronary, pulmonary or cerebral) involves well-known surgical procedures and the use of many conventional commercially available auxiliary products. These products, such as angiographic materials, mechanical thrombectomy devices, microcatheters and guidewires, are widely used in laboratories and medical procedures. When these products are used in conjunction with the apparatus and methods of the present invention described below, their functions and exact constructions are not described in detail. In addition, although this specification is in many cases in the context of thrombectomy treatment of intracranial arteries, the disclosure may also be applicable to other procedures and other body passages.

[0071] Turning to the attached figure, Figures 1A to 1E An exemplary expandable support frame 210 for use in a clot retrieval catheter tip is shown. When used in conjunction with an LST catheter, the support frame 210 may be manufactured using superelastic nickel titanium or nitinol (NiTi), shape memory NiTi, or stainless steel. Although the LST catheter does not require a shape memory material, it can provide the additional benefit of enabling the support frame 210 to recover its shape if deformed during use, or if the support frame 210 is expanded by a clot during a first retrieval and needs to be easily recovered to be returned through the guide sheath for a second retrieval. When used in conjunction with a CSB catheter, the shape memory material enables the support frame 210 to self-expand as it exits the distal end of the catheter tip and approaches a clot for retrieval. The shape memory alloy used may include an austenite finish temperature of less than approximately 30 degrees Celsius.

[0072] The support frame 210 can be manufactured by taking a raw tubing of the material as discussed above and laser cutting the material to produce the desired configuration of the support frame 210, as will be further described below. The raw tubing can have an outer diameter of approximately 2.00 mm, a wall thickness of approximately 0.05 mm, and an inner diameter of approximately 1.90 mm. The support frame 210 can also be manufactured with a light electropolishing or other such surface treatment. A matte finish can provide the benefit of enhanced adhesion to a polymer catheter jacket.

[0073] The support frame 210 may include a longitudinal axis 111, a collapsed delivery configuration ( Figures 1A to 1C), expansion deployment configuration ( FIG. 10B to FIG. 10C or Fig. 11C ), and a plurality of interconnecting struts 218 defining an axial series of expansion units 221. The interconnecting struts 218 may be joined at opposing pairs of x-connectors 217 that are spaced 180 degrees apart around the longitudinal axis 111. Each opposing pair of x-connectors 217 may be rotated 90 degrees around the longitudinal axis 111 relative to an adjacent opposing pair of x-connectors 217, such as Figure 1A Such a rotational configuration may provide enhanced flexibility of the support frame 210 across multiple planes compared to many conventional support frame designs.

[0074] like Figure 1B to Figure 1C As shown in particular, the support frame 210 may include distal strut angles 219 between struts 218 on opposite sides of the longitudinal axis 111. The distal strut angles 219 may be configured as an obtuse angle so that they can provide enhanced flexibility and compressibility during clot retrieval, as further described below. The struts 218 may also include a curved profile to aid in the flexibility of the support frame 210. That is, when the support frame 210 is placed in a compressed state ( Fig. 10C and Fig. 11C ), a series of expansion units 221 can be shortened longitudinally. Thus, the support frame 210 may include an axial length 225 ( Figure 1C ), the axial length may be smaller in the expanded deployment configuration than in the collapsed delivery configuration, as shown below with respect to FIG. 10A to FIG. 10C and FIG. 11A to FIG. 11C Further discussion.

[0075] like Figure 1B Specifically shown, the axial series of expansion units 221 may include opposing pairs of units spaced 180 degrees apart about the longitudinal axis 111. Each opposing pair of units may also be rotated 90 degrees about the longitudinal axis 111 relative to an adjacent opposing pair of units.

[0076] When in the collapsed delivery configuration, the distal end 114 of the support frame 210 may include a substantially circular cross-section with a center substantially coincident with the longitudinal axis, such as Figure 1A to Figure 1B As specifically shown and as further described below.

[0077] The support frame 210 may also include a proximal collar 115 at its proximal end 112. The proximal collar 115 may be used to attach the support frame 210 to a braided shaft of a clot retrieval catheter. The proximal collar 115 may include a ring member 116 that is formed by at least one seam 117 ( Figure 1A) (such as an angled seam) circumferentially separated, which facilitates assembly of the proximal loop 115. In some embodiments, the ring member 116 can be configured to be connected to a braided segment of a tubular catheter shaft. For example, the ring member 116 can be configured to be press-fit onto the braided segment, or can be laser welded to the braided segment (e.g., fit under or over the braided segment). In other examples, the ring member 116 can be adhesively bonded to the braided segment. In some embodiments, the ring member 116 can be integrally formed with and / or laser welded to a laser-cut proximal catheter support structure, rather than a braided segment.

[0078] like Figure 1A to Figure 1B As shown, the support frame 210 may include a port 213 at the distal end 114, the port 213 having an offset port strut 220. At least a portion of the offset port strut 220 may be located in a plane that forms an acute angle 222 relative to the longitudinal axis 111. As shown, the offset port strut 220 may be connected to one or more struts 218 via one or more y connectors 223. The benefit of the offset port strut 220 is that it allows a larger space for clots to enter the catheter end. Compared to many conventional support frame designs, this can provide easier and more effective clot retrieval from the treatment site and can reduce the risk of clot shearing or breakage during retrieval. The offset port can also allow for increased clot clamping force due to the larger area of ​​the port compared to the circular cross-section of the catheter.

[0079] like Figure 1D to Figure 1E As shown, the support frame 210 can include a collapsed inner diameter 215 ( Figure 1D ), and includes a larger inner diameter 224 ( Figure 1E The collapsed inner diameter 215 enables the support frame 210 to fit within the guide sheath 30 as the catheter is navigated through the vessel 12 toward the treatment site. Fig. 10A ). As follows, FIG. 11A to FIG. 11C As further described, when used in conjunction with an LST catheter, the support frame 210 can maintain its collapsed inner diameter 215 as it exits the distal end 32 of the introducer sheath 30, and then expand from the collapsed inner diameter 215 to the expanded inner diameter 224 when struck by an ingested clot 40. Alternatively, when used in conjunction with a CSB catheter, as will be described below with respect to FIG. 10A to FIG. 10C As further described, the support frame 210 can be heat set so that once the support frame 210 leaves the distal end 32 of the guide sheath 30, the support frame has an expanded inner diameter 224 that is larger than the collapsed inner diameter 215. In some embodiments, when used in conjunction with an LST or CSB catheter, for example, when the support frame 210 is in its expanded deployment configuration ( FIG. 10B to FIG. 10C and Fig. 11C), whose maximum outer diameter can be smaller than the inner diameter 13 of the target vessel 12 at the treatment site, so that the support frame 210 can be independent of the vessel 12 and advanced distally toward the clot 40 without sealing to the vessel. In some embodiments, such as when used in conjunction with a CSB catheter, the maximum outer diameter of the support frame 210 can be larger than the inner diameter 13 of the target vessel 12. In such embodiments, the support frame 210 can be configured to self-collapse when advanced distally through a smaller vessel so that it can provide a seal within the vessel.

[0080] With respect to the various support frames disclosed herein, the inner and outer diameters of the support frame, when in the collapsed delivery configuration and the expanded deployment configuration, can depend on the size of the catheter used in conjunction with the support frame.

[0081] For example, when a support frame is used in conjunction with a 5 Fr low shear tip, the collapsed inner diameter can be approximately 0.054 inches, while the collapsed outer diameter can be approximately 0.066 inches. A support frame of this size can be used in a target vessel having an inner diameter of approximately 1.7 mm in its collapsed configuration, while in its expanded configuration, a support frame of this size can be expanded to seal in a target vessel having an inner diameter of approximately 2.2 mm.

[0082] For example, when the support frame is used in conjunction with a 6 Fr low shear tip, the collapsed inner diameter can be in the range of about 0.068 inches to about 0.074 inches, while the collapsed outer diameter can be in the range of about 0.080 inches to about 0.086 inches. A support frame of this size can be used in a target vessel having an inner diameter of about 2.0 mm to 2.2 mm in its collapsed configuration, and in its expanded configuration, a support frame of this size can be expanded to seal in a target vessel having an inner diameter of about 3.5 mm.

[0083] For example, when the support frame is used in conjunction with an 8 Fr low shear tip, the collapsed inner diameter can be in the range of about 0.082 inches to about 0.095 inches, while the collapsed outer diameter can be in the range of about 0.094 inches to about 0.115 inches. A support frame of this size can be used in a target vessel having an inner diameter of about 2.4 mm to 2.9 mm, and in its expanded configuration, a support frame of this size can be expanded to seal in a target vessel having an inner diameter of about 5.0 mm.

[0084] FIG. 2A to FIG. 2DAnother exemplary expandable support frame 310 for use in a clot retrieval catheter tip is shown. The support frame 310 may include one or more features that are the same or similar to those described above with respect to the support frame 210. In addition, the manufacture of the support frame 310 may be the same or similar to the manufacture of the support frame 210, as discussed above. The support frame 310 may also be manufactured to be electropolished, pickled to roughen the surface of the support frame 310, and / or heat treated to have an oxide finish.

[0085] The support frame 310 may include a longitudinal axis 111, a collapsed delivery configuration ( FIG. 2A to FIG. 2C ), an expanded deployment configuration, and a plurality of interconnected struts 318 defining an axial series of expansion units 321. The interconnected struts 318 may be joined at opposing pairs of x-connectors 317 that are spaced 180 degrees apart about the longitudinal axis 111. Each opposing pair of x-connectors 317 may be rotated 90 degrees about the longitudinal axis 111 relative to an adjacent opposing pair of x-connectors 317. Such a rotational configuration may provide enhanced flexibility of the support frame 310 across multiple planes compared to many conventional support frame designs.

[0086] The support frame 310 may also include distal strut angles 319 between struts 318 on opposite sides of the longitudinal axis 111, such as Figure 2C As shown in detail, the distal strut angle 319 can be configured as an acute angle due to the increased length of its x-connector strut 317. The acute distal strut angle 319 can provide increased expansion of the support frame 310 compared to many conventional support frame designs, and the increased length of the x-connector strut 317 can provide less restricted bending.

[0087] like Figure 2C As shown, the interconnecting struts 318 may also include a curved profile to facilitate flexibility of the support frame 310. That is, when the support frame 310 is placed in a compressed state, the series of expansion units 321 may be shortened longitudinally. Figure 2C As shown, the support frame 310 may include an axial length 325 that may be smaller in the expanded deployment configuration than in the collapsed delivery configuration, as described below with respect to FIG. 10A to FIG. 10C and FIG. 11A to FIG. 11C The support frame 210 is further discussed in detail.

[0088] Also like Figure 2C Specifically, the axial series of expansion units 321 may include opposing pairs of units spaced 180 degrees apart about the longitudinal axis 111. Each opposing pair of units may also be rotated 90 degrees about the longitudinal axis 111 relative to the adjacent opposing pair of units. In some embodiments, the support frame 310 may be modified to have a variable spacing relative to the expansion units 321, such as Figure 2D Variable cell spacing can allow for gradual expansion during compression of the support frame 310 and can provide enhanced lateral flexibility at the proximal end of the support frame 310 (e.g., near the proximal collar 115), as discussed further below. It should be understood that any of the various support frames disclosed herein can be modified to have variable cell spacing.

[0089] When in the collapsed delivery configuration, the distal end 114 of the support frame 310 may include a substantially circular cross-section with a center substantially coincident with the longitudinal axis, such as Figure 2A and Figure 2C As specifically shown and as further described below.

[0090] The support frame 310 may also include a proximal collar 115 at its proximal end 112. The proximal collar 115 may be used to attach the support frame 310 to a braided shaft of a clot retrieval catheter. The proximal collar 115 may include a ring member 116 that is circumferentially separated by at least one seam 117, such as an angled seam, which facilitates assembly of the proximal collar 115.

[0091] like Figure 2A and Figure 2C As shown, the support frame 310 may include a port 313 at the distal end 114, the port 313 having an offset port strut 320. At least a portion of the offset port strut 320 may be located in a plane that forms an acute angle 322 relative to the longitudinal axis 111. The benefit of the offset port strut 320 is that it can allow for more space for clots to enter the catheter tip. This can provide easier and more efficient clot retrieval from the treatment site compared to many conventional support frame designs, and can reduce the risk of clot shearing or breakage during retrieval.

[0092] Similar to the support frame 210, as described above with respect to Figure 1D to Figure 1EAs described, the support frame 310 may include a collapsed inner diameter when in a collapsed delivery configuration, and include a larger expanded inner diameter in an expanded deployment configuration when the support frame 310 is placed in a compressed state. In some embodiments, when used in conjunction with an LST or CSB catheter, for example, when the support frame 310 is in its expanded deployment configuration, its maximum outer diameter may be less than the inner diameter 13 of the target vessel 12 at the treatment site, so that the support frame 310 can be independent of the vessel 12 and advanced distally toward the clot 40 without sealing to the vessel. In some embodiments, for example, when used in conjunction with a CSB catheter, the support frame 310 may have an outer diameter greater than the inner diameter of the target vessel 12, and be configured to self-collapse when advanced distally through the target vessel. For example, the catheter tip including the support frame 310 may be configured such that when the support frame 310 is advanced through a vessel 12 that may decrease distally relative to its inner diameter, the radial collapse force is reduced, while still maintaining a high enough resistance to compression so that the tip remains open under full vacuum when occluded. This may allow a catheter having support frame 310 to be used in a wide range of vessel sizes.

[0093] Figures 3A to 3G Another exemplary expandable support frame 410 for use in a clot retrieval catheter tip is shown. Support frame 410 may include one or more features that are the same or similar to those described with respect to support frames 210 and 310. In addition, the manufacture of support frame 410 may be the same or similar to the manufacture of support frames 210 and 310. Support frame 410 may also be manufactured to be electropolished, pickled to roughen the surface of support frame 410, and / or heat treated to have an oxide finish.

[0094] The support frame 410 may include a longitudinal axis 111, a collapsed delivery configuration ( FIG. 4A to FIG. 4C ), an expanded deployment configuration, and a plurality of interconnected struts 418 defining an axial series of expansion units 421. The interconnected struts 418 may be joined at opposing pairs of x-connectors 417 that are spaced 180 degrees apart about the longitudinal axis 111. Each opposing pair of x-connectors 417 may be rotated 90 degrees about the longitudinal axis 111 relative to an adjacent opposing pair of x-connectors 417. Such a rotational configuration may also provide enhanced flexibility of the support frame 410 across multiple planes compared to many conventional support frame designs.

[0095] In some embodiments, the interconnecting pillars 418 may be connected to opposing pairs of u connectors 417i (eg, Figure 3D As shown), s connector 417ii (as Figure 3E as shown) and / or m / w connector 417iii (as shown Figure 3FThe use of different connector types and / or shapes between the interconnecting struts 418 can provide variations in the lateral flexibility of the support frame 410. It should be understood that different connector types and / or shapes can be used in the various support frames disclosed herein.

[0096] The support frame 410 may also include distal strut angles 419 between struts 418 on opposite sides of the longitudinal axis 111, such as FIG. 3C to FIG. 3F As shown in detail, the distal support angle 419 can be due to its x connector support 417 ( Figure 3A ) is configured as an acute angle. The acute distal strut angle 419 can provide increased expansion of the support frame 410 compared to many conventional support frame designs, and the increased length of the x-connector struts 417 can provide less restricted bending.

[0097] like FIG. 3A to FIG. 3F As shown, the support frame 410 may also include one or more additional v-struts 423. The additional v-struts 423 may allow for increased radial force and compression resistance, particularly in light of the acute distal strut angles 419, compared to many conventional support frame designs.

[0098] like Figure 3B As shown, the interconnecting struts 418 may also include a curved profile to facilitate flexibility of the support frame 410. That is, when the support frame 410 is placed in a compressed state, the series of expansion units 421 may be shortened longitudinally. FIG. 3C to FIG. 3F As shown, the support frame 410 may include an axial length 425 that may be smaller in the expanded deployment configuration than in the collapsed delivery configuration, as described below with respect to FIG. 10A to FIG. 10C and FIG. 11A to FIG. 11C The support frame 210 is further discussed in detail.

[0099] Also like FIG. 3C to FIG. 3F Specifically shown, the axial series of expansion units 421 may include opposing pairs of units spaced 180 degrees apart about the longitudinal axis 111. Each opposing pair of units may also be rotated 90 degrees about the longitudinal axis 111 relative to an adjacent opposing pair of units.

[0100] When in the collapsed delivery configuration, the distal end 114 of the support frame 410 may include a substantially circular cross-section with a center substantially coincident with the longitudinal axis, such as Figure 3A and FIG. 3C to FIG. 3F As shown in detail, and as discussed further below.

[0101] The support frame 410 may include a proximal collar 115 at its proximal end 112. The proximal collar 115 may be used to attach the support frame 410 to a braided shaft of a clot retrieval catheter. The proximal collar 115 may include a ring member 116 that is circumferentially separated by at least one seam 117, such as an angled seam, which facilitates assembly of the proximal collar 115.

[0102] like Figure 3A and FIG. 3C to FIG. 3F As shown, the support frame 410 may include a port 413 at the distal end 114, the port 413 having an offset port strut 420. At least a portion of the offset port strut 420 may be located in a plane that forms an acute angle 422 relative to the longitudinal axis 111. The benefit of the offset port strut 420 is that it allows a larger space for the clot to enter the catheter tip. Compared with many conventional support frame designs, this can provide easier and more efficient clot retrieval from the treatment site and can reduce the risk of clot shearing or breakage during retrieval. For hard, fibrin-rich clots that cannot be completely aspirated through the inner diameter of the catheter, the offset port can provide a larger surface area to increase the clot holding force and enable the tip to grab the clot and retract it from the vessel and into a larger guide catheter positioned more proximally in the vessel.

[0103] In some embodiments, the port 413 of the support frame 410 (or the port of any other support frame disclosed herein) can be arranged in two planes, such as in the shape of two opposing struts 413a and 413b. The two opposing struts 413a, 413b can be configured to follow the shape of the distal-most struts of the support frame 410 so that the surface area of ​​the port 413 can be arranged in two planes. In such embodiments, the port 413 can have an increased surface area over a shorter length and can allow suction from two opposing sides of the distal tip of the catheter.

[0104] Similar to support frames 210 and 310, support frame 410 can include a collapsed inner diameter when in a collapsed delivery configuration, and a larger expanded inner diameter in an expanded deployment configuration when support frame 410 is placed in a compressed state. In some embodiments, when used in conjunction with an LST or CSB catheter, for example, when support frame 410 is in its expanded deployment configuration, its maximum outer diameter can be less than the inner diameter 13 of a target vessel 12 at a treatment site, such that support frame 410 can be independent of vessel 12 and advanced distally toward clot 40 without sealing to the vessel. In some embodiments, such as when used in conjunction with a CSB catheter, support frame 410 can have an outer diameter greater than the inner diameter of target vessel 12 and be configured to self-collapse when advanced distally through the target vessel. For example, a catheter tip including support frame 410 can be configured such that when support frame 410 is advanced through a vessel 12 that may decrease distally relative to its inner diameter, the radial collapse force is reduced while still maintaining a high enough resistance to compression that the tip remains open under full vacuum when occluded. This can allow a catheter with support frame 410 to be used in a wide range of vessel sizes.

[0105] FIG. 4A to FIG. 4C Another exemplary expandable support frame 510 for use in a clot retrieval catheter tip is shown. The support frame 510 may include one or more features that are the same or similar to those described with respect to the support frames 210, 310, and 410. When used in conjunction with an LST or CSB catheter, the manufacture of the support frame 510 may be the same or similar to the manufacture of the support frames 210, 310, and 410 as discussed above. The support frame 510 may also be manufactured to be electropolished, pickled to roughen the surface of the support frame 510, and / or heat treated to have an oxide finish.

[0106] The support frame 510 may include a longitudinal axis 111, a collapsed delivery configuration ( FIG. 4A to FIG. 4C ), an expanded deployment configuration, and an axial series of hoop ribs 517 extending in a plane offset from the longitudinal axis 111. The hoop ribs 517 may include a curved profile, a non-planar cross-section, and a distal unconnected peak 518. The support frame 510 may also include a port 513 that, when the support frame 510 is placed in a compressed state ( Fig. 10C and Fig. 11C ), the mouth has a larger expanded inner diameter.

[0107] When the support frame 510 is in compression during clot ingestion, the distal unconnected peaks 518 of each of the ribs 517 can move proximally. This feature can allow the clot 40 to collect more easily in the support frame 510 during retrieval than many conventional support frame designs.

[0108] like Figure 4C As particularly shown, at least a portion of each of the hoop ribs 517 may lie in a plane that forms an acute angle 522 relative to the longitudinal axis 111 .

[0109] like Figure 4A As shown, each of the hoop ribs 517 may also be connected to the proximal collar 115 at a connection point 519. This feature may help minimize the stiffness of the support frame 510. The proximal collar 115 may be used to attach the support frame 510 to a braided shaft of a clot retrieval catheter. The proximal collar 115 may include a ring member 116 that is circumferentially separated by at least one seam 117, such as an angled seam, which facilitates assembly of the proximal collar 115.

[0110] like Figure 4C As shown, the support frame 510 may include an axial length 525 that may be smaller in the expanded deployment configuration than in the collapsed delivery configuration, as described below with respect to FIG. 10A to FIG. 10C and FIG. 11A to FIG. 11C The support frame 210 is further discussed in detail.

[0111] Similar to the above Figure 1D to Figure 1E As discussed above, support frame 210, support frame 510 may include a larger expanded inner diameter 224 ( Figure 1E ) and a smaller delivery inner diameter 215 ( Figure 1D The collapsed inner diameter 215 enables the support frame 210 to fit within the guide sheath 30 as the catheter is navigated through the vessel 12 toward the treatment site. Fig. 10A ). As follows, FIG. 11A to FIG. 11C As further described, when used in conjunction with an LST catheter, the support frame 510 can maintain its collapsed inner diameter 215 as it exits the distal end 32 of the introducer sheath 30, and then expand from the collapsed inner diameter 215 to the expanded inner diameter 224 when struck by an ingested clot 40. Alternatively, when used in conjunction with a CSB catheter, as will be described below with respect to FIG. 10A to FIG. 10C As further described, the support frame 510 can be heat set so that once the support frame 510 exits the distal end 32 of the introducer sheath 30, the support frame has an expanded inner diameter 224 that is greater than the collapsed inner diameter 215. When used in conjunction with an LST or CSB catheter, when the support frame 510 is in its expanded deployed configuration, its maximum outer diameter can be less than the inner diameter 13 of the target vessel 12 at the treatment site, so that the support frame 510 can be independent of the vessel 12 and advanced distally toward the clot 40 without sealing to the vessel.

[0112] When in the collapsed delivery configuration, the distal end 114 of the support frame 510 may include a substantially circular cross-section with a center substantially coincident with the longitudinal axis 111, as shown in FIG. Figure 4A and Figure 4C As specifically shown and as further described below.

[0113] FIG. 5A to FIG. 5C Another exemplary expandable support frame 610 for use in a clot retrieval catheter tip is shown. The support frame 610 may include one or more features that are the same or similar to those described with respect to the support frames 210, 310, 410, and 510. When used in conjunction with an LST or CSB catheter, the manufacture of the support frame 610 may be the same or similar to the manufacture of the support frames 210, 310, 410, and 510 discussed above. The support frame 610 may also be manufactured to be electropolished, pickled to roughen the surface of the support frame 610, and / or heat treated to have an oxide finish.

[0114] The support frame 610 may include a longitudinal axis 111, a collapsed delivery configuration ( FIG. 5A to FIG. 5C ), an expanded deployment configuration, and an axial series of hoop ribs 617 extending in a plane offset from the longitudinal axis 111. The hoop ribs 617 may include a curved profile, a non-planar cross-section, and a distal unconnected peak 618. The support frame 610 may also include a port 613 that allows the support frame 610 to be placed in a compressed state ( Fig. 10C and Fig. 11C ), the mouth has a larger expanded inner diameter.

[0115] When the support frame 610 is in compression during clot ingestion, the distal unconnected peaks 618 of each of the ribs 617 can move proximally. This feature can allow the clot 40 to accumulate more easily in the support frame 610 during retrieval than many conventional support frame designs.

[0116] like Figure 5C As particularly shown, at least a portion of each of the hoop ribs 617 may lie in a plane that forms an acute angle 622 relative to the longitudinal axis 111 .

[0117] like Figure 5A As shown, at least one hoop rib 617 can be directly connected to the proximal collar 115 at a connection point 619. One or more other hoop ribs 617 can alternatively be connected to one or more connector ribs 620 at one or more connection points 619. The connector ribs 620 can extend from the ring member 116 connected to the proximal end 112 of the support frame 610. The connector ribs 620 can diverge from the ring member 116 in an offset plane that is substantially perpendicular to the offset plane of the hoop ribs 617, as shown in FIG. Figure 5CAs shown in detail, connector ribs 620 can help increase the flexibility of support frame 610 during stapling and can allow for more symmetrical expansion during clot retrieval compared to many conventional support frame designs.

[0118] like Figure 5C As particularly shown, one or more of the hoop ribs 617 may also include a first curve 623 and a second curve 624 to facilitate flexibility of the support frame 610 during expansion and clot retrieval.

[0119] Similar to other support frames discussed herein, support frame 610 may also include an axial length that may be smaller in the expanded deployment configuration than in the collapsed delivery configuration, as described below with respect to FIG. 10A to FIG. 10C and FIG. 11A to FIG. 11C Further discussion.

[0120] Similar to the above Figure 1D to Figure 1E As discussed above, support frame 210, support frame 610 may include a larger expanded inner diameter 224 ( Figure 1E ) and a smaller delivery inner diameter 215 ( Figure 1D ). When used in conjunction with an LST or CSB catheter, support frame 610 may include one or more of the same or similar features as support frame 510, as discussed above.

[0121] When in the collapsed delivery configuration, the distal end 114 of the support frame 610 may include a substantially circular cross-section with a center substantially coincident with the longitudinal axis 111, as shown in FIG. Figure 5A and Figure 5C As specifically shown and as further described below.

[0122] FIG. 6A to FIG. 6C Another exemplary expandable support frame 710 for use in a clot retrieval catheter tip is shown. The support frame 710 may include one or more features that are the same or similar to those described with respect to the support frames 210, 310, 410, 510, and 610. When used in conjunction with an LST or CSB catheter, the manufacture of the support frame 710 may be the same or similar to the manufacture of the support frames 210, 310, 410, 510, and 610 discussed above. The support frame 710 may also be manufactured to be electropolished, pickled to roughen the surface of the support frame 710, and / or heat treated to have an oxide finish.

[0123] The support frame 710 may include a longitudinal axis 111, a collapsed delivery configuration ( FIG. 6A to FIG. 6C), an expanded deployment configuration, and an axial series of hoop ribs 717 extending in a plane offset from the longitudinal axis 111. The hoop ribs 717 may include a curved profile, a non-planar cross-section, and a distal unconnected peak 718. The support frame 710 may also include a port 713 that allows the support frame 710 to be placed in a compressed state ( Fig. 10C and Fig. 11C ), the mouth has a larger expanded inner diameter.

[0124] When the support frame 710 is in compression during clot ingestion, the distal unconnected peaks 718 of each of the ribs 717 can move proximally. This feature can allow the clot 40 to accumulate more easily in the support frame 710 during retrieval than many conventional support frame designs.

[0125] like Figure 6C As particularly shown, at least a portion of each of the hoop ribs 717 may lie in an offset plane 721 that forms an acute angle 722 relative to the longitudinal axis 111 .

[0126] like Fig. 6A As shown, at least one hoop rib 717 can be directly connected to the proximal collar 115 at a connection point 719. One or more other hoop ribs 717 can alternatively be connected to one or more connector ribs 720 at one or more connection points 719. The connector ribs 720 can extend from the ring member 116 connected to the proximal end 112 of the support frame 710. The connector ribs 720 can diverge from the ring member 116 in an offset plane 727 that is substantially perpendicular to the offset plane 721 of the hoop ribs 717, as shown in FIG. Figure 6C As shown in detail, connector ribs 720 can help increase the flexibility of support frame 710 during stapling and can allow for more symmetrical expansion during clot retrieval compared to many conventional support frame designs.

[0127] The support frame 710 may also include one or more support ribs 726 extending from the ring member 116 in a plane that is substantially parallel to an offset plane 727 of the connector ribs 720. The support ribs 726 may have no connection points to any of the series of hoop ribs 717 or the connector ribs 720, which may allow for a greater degree of expansion and more symmetrical expansion than many conventional support frame designs.

[0128] like Figure 6C As particularly shown, one or more of the hoop ribs 717 may also include a first curve 623 and a second curve 624 to facilitate flexibility of the support frame 710 during expansion and clot retrieval.

[0129] Figure 7 and Figure 8An example of a catheter shaft profile 110 is shown when the support frame described herein is in its expanded deployed configuration and used in conjunction with a CSB or LST catheter.

[0130] Figure 7 An example of a catheter shaft profile 110 is shown. The shaft profile 110 may include a circular profile that is symmetrical about a longitudinal axis 111. That is, the shaft 110 may include an end segment 810 that includes a proximal end 812, a distal end 814, and a funnel profile 816 disposed between the proximal end 812 and the distal end 814. The funnel profile 816 and the segments distal and proximal to the funnel profile 816 may be symmetrical about the longitudinal axis 111. The symmetrical nature of the shaft profile 110 may be based on the support frame being heat-set so that when leaving the distal end 32 of the guide sheath 30 ( Fig. 10B ), the support frame can expand to an expanded inner diameter 224.

[0131] Figure 8 Another example of a catheter shaft profile 110 is shown. The funnel profile 816 can include a center 818 that is radially offset from the longitudinal axis 111. That is, the center 818 can be centered relative to the offset axis 811, thereby configuring the funnel profile 816 to be offset relative to the longitudinal axis 111.

[0132] Fig. 9 A possible sequence of approaching an obstructive clot 40 using a large-bore clot retrieval catheter 100 used in conjunction with the support frame design disclosed herein is shown. As the catheter 100 collapses within the guide sheath 30 or other access catheter, the clot 40 can be approached. When the vasculature 10 becomes too narrow and / or tortuous to navigate further distally with the guide sheath 30, the catheter 100 can be deployed to advance further distally independently. The catheter 100 can be highly flexible, enabling it to navigate the M1 or other tortuous regions of the neurovascular system to reach the obstructive clot. As discussed herein, the catheter 100 can have an expanded outer diameter that is slightly smaller than the outer diameter of the target vessel, enabling the catheter to be independently navigated distally after deployment, or the catheter can be sized to be larger than the target vessel and can be configured to compress radially so that it can be used to treat smaller sized vessels.

[0133] The clot retrieval catheter 100 may have a flexible, elongated body 110 that serves as a shaft with a large inner caliber (in some cases, may be 0.080 inches or larger); and a distal tip segment having a collapsible support frame of the design disclosed herein, such as support frame 210. The large caliber facilitates delivery of the catheter to the target site by a variety of methods. These methods may include over a guidewire, over a microcatheter, with a dilator / access tool, or by itself.

[0134] In many cases, the design of the tip can be configured so that the entire catheter 100 can be delivered (and retrieved) through a common standard 6F sheath / 8F guide, which typically has a lumen of less than 0.090 inches. The tip is self-expanding once it is advanced to an unconstrained position distal to the distal end 32 of the guide sheath 30. Because the catheter can be deployed proximal to a distal obstruction and then advanced to the distal obstruction alone, the support frame of the tip is designed to resist collapse caused by suction forces, has excellent lateral flexibility in both expanded and collapsed states, and has an atraumatic profile that prevents obstruction of vascular bifurcations.

[0135] FIG. 10A to FIG. 10C Exemplary treatment steps for using a clot retrieval catheter expandable support frame of the design disclosed herein in conjunction with a CSB catheter as described above are shown. FIG. 10A to FIG. 10C The use of support frame 210 is shown, but other support frames described herein (e.g., 310, 410, 510, 610, 710) may be used in the same or similar series of treatment steps. Fig. 10A As the catheter tip moves through the target vessel 12 toward the clot 40 ( Fig. 10B ), a support frame 210 within the catheter shaft 110 and within the distal end 32 of the guide sheath 30. As shown, the support frame 210 includes a collapsed inner diameter 215 when within the guide sheath 30 in its collapsed delivery configuration.

[0136] Fig. 10B The support frame 210 is shown transitioning to its expanded deployed configuration as it exits the distal end 32 of the guide sheath 30. As described above, when used in conjunction with a CSB catheter, the support frame 210 can be heat set so that upon exiting the distal end 32 of the guide sheath 30, the support frame 210 can expand to an expanded inner diameter 224 that is greater than the collapsed inner diameter 215. The funnel profile 816 of the support frame 210 can also be symmetrical about the longitudinal axis 111, as described above with respect to Figure 7 However, even when in its expanded deployed configuration, the maximum outer diameter of the support frame 210 can be less than the inner diameter 13 of the target vessel 12 so that the support frame 210 can be independent of the vessel 12 and advanced distally toward the clot 40 without sealing to the vessel.

[0137] Fig. 10C Port 213 of support frame 210 is shown encasing a proximal portion of clot 40. As shown and discussed above, when support frame 210 is placed in a compressed state against and / or around clot 40, it can shorten longitudinally.

[0138] FIG. 11A to FIG. 11CExemplary treatment steps for using a clot retrieval catheter expandable support frame of the design disclosed herein in conjunction with an LST catheter as described above are shown. FIG. 11A to FIG. 11C The use of support frame 210 is shown, but other support frames described herein (e.g., 310, 410, 510, 610, 710) may be used in the same or similar series of treatment steps. Fig.11A As the catheter tip moves through the target vessel 12 toward the clot 40 ( Fig. 11B ), a support frame 210 within the catheter shaft 110 and within the distal end 32 of the guide sheath 30. As shown, the support frame 210 includes a collapsed inner diameter 215 when within the guide sheath 30 in its collapsed delivery configuration.

[0139] Fig. 11B The support frame 210 is shown exiting the distal end 32 of the guide sheath 30. As described above, when used in conjunction with the LST catheter, the support frame 210 can maintain its collapsed inner diameter 215 when exiting the distal end 32 of the guide sheath 30. As shown, the distal end section 810 of the support frame 210 begins to align with the oblique ostial plane 821.

[0140] Fig. 11C The mouth 213 of the support frame 210 is shown enveloping the proximal portion of the clot 40. As shown and discussed above, when the support frame 210 is placed in a compressed state against and / or around the clot 40, it can be longitudinally shortened. In addition, the funnel profile 816 can be radially offset from the longitudinal axis 111, as described above with respect to Figure 8 and similarly to when the support frame 210 is used in conjunction with a CSB catheter ( FIG. 10A to FIG. 10C ), even when in its expanded deployed configuration, the maximum outer diameter of the support frame 210 can be less than the inner diameter 13 of the target vessel 12, so that the support frame 210 can be independent of the vessel 12 and advanced distally toward the clot 40 without sealing to the vessel.

[0141] The present invention is not necessarily limited to the examples described, the configurations and details of which may vary. The terms "distal" and "proximal" are used throughout the foregoing description and refer to positions and directions relative to the treating physician. Similarly, "distal" or "toward the distal side" refers to a position away from the physician or in a direction away from the physician. Similarly, "proximal" or "toward the proximal side" refers to a position close to the physician or in a direction toward the physician. In addition, unless the context clearly indicates otherwise, the singular forms "a", "an", and "the / said" include plural references.

[0142] As used herein, the term "about" or "approximately" for any numerical value or range indicates a suitable dimensional tolerance that allows a collection of parts or components to achieve its intended purpose as described herein. More specifically, "about" or "approximately" can refer to a value range of ±20% of the recited value, for example, "about 90%" can refer to a value range of 71% to 99%.

[0143] In describing the example embodiments, terminology has been employed for the sake of clarity. Therefore, not all possible combinations are listed, and such variations are generally obvious to those skilled in the art and are intended to fall within the scope of the following claims. Without departing from the scope and spirit of the present invention, it is intended that each term contemplates the broadest meaning understood by those skilled in the relevant art, and includes all technical equivalents that operate in a similar manner to achieve similar purposes. It should also be understood that reference to one or more steps of a method does not exclude the presence of additional method steps or intermediate method steps between those explicitly identified steps. Similarly, some steps of the method may be performed in an order different from that described herein without departing from the scope of the disclosed technology.

Claims

1. A catheter tip, comprising: a. a support frame comprising a longitudinal axis, a collapsed delivery configuration, an expanded deployment configuration, and a plurality of interconnected struts defining an axial series of expansion units, the interconnected struts being joined at opposing pairs of x-connectors spaced 180 degrees apart around the longitudinal axis; b. Each pair of opposite x connectors is rotated 90 degrees about the longitudinal axis relative to an adjacent pair of opposite x connectors; and c. The support frame further comprises a collapsed inner diameter in the collapsed delivery configuration and a larger expanded inner diameter in the expanded deployment configuration when the support frame is placed in a compressed state.

2. The catheter tip of claim 1, the support frame further comprising a proximal collar at a proximal end of the support frame.

3. The catheter tip of claim 1, the interconnecting struts comprising a curved profile.

4. The catheter tip of claim 1, the support frame further comprising a shape memory alloy having an austenite finish temperature of less than about 30 degrees Celsius.

5. The catheter tip of claim 1, wherein the support frame expands from the collapsed inner diameter to the expanded inner diameter when impacted by an ingested clot.

6. The catheter tip of claim 4, the support frame being heat set to have the expanded inner diameter greater than the collapsed inner diameter.

7. The catheter tip of claim 1, wherein the support frame further comprises an axial length that is smaller in the expanded deployment configuration than in the collapsed delivery configuration.

8. The catheter tip of claim 1, wherein the series of expansion units are longitudinally shortened when the support frame is placed in a compressed state.

9. The catheter tip of claim 1, wherein the axial series of expansion units comprises opposing pairs of units spaced 180 degrees apart about the longitudinal axis; and Each opposing pair of cells is rotated 90 degrees about the longitudinal axis relative to an adjacent opposing pair of cells.

10. The catheter tip of claim 1 further comprising an offset port strut at a distal end of the support frame, at least a portion of the offset port strut lying in a plane forming an acute angle relative to the longitudinal axis.

11. The catheter tip of claim 1, the support frame further comprising a maximum outer diameter in the expanded deployed configuration, the maximum outer diameter being smaller than or larger than an inner diameter of a target vessel at a treatment site.

12. The catheter tip of claim 1, wherein in the collapsed delivery configuration, the distal end of the support frame further comprises a substantially circular cross-section with a center substantially coincident with the longitudinal axis.

13. A catheter tip, comprising: a support frame comprising a longitudinal axis, a collapsed delivery configuration, an expanded deployment configuration, and an axial series of hoop ribs extending in a plane offset from the longitudinal axis; The hoop rib comprises a curvilinear profile, a non-planar cross-section, and distal unconnected peaks; and When the support frame is placed in a compressed state, the mouth of the support frame has a larger expanded inner diameter.

14. The catheter tip of claim 13, the support frame further comprising a shape memory alloy having an austenite finish temperature of less than about 30 degrees Celsius.

15. The catheter tip of claim 13, the distal unconnected peak of each of the ribs moving proximally when the support frame is in compression during clot uptake.

16. The catheter tip of claim 13, at least a portion of each of the ribs lying in a plane that forms an acute angle with respect to the longitudinal axis.

17. The catheter tip of claim 13, the support frame further comprising a larger expanded inner diameter in the expanded deployment configuration when radially impacted by an ingested clot, and a smaller delivery inner diameter in the collapsed delivery configuration.

18. The catheter tip of claim 14, the support frame being heat set to have the expanded inner diameter greater than the inner diameter of the collapsed delivery configuration.

19. The catheter tip of claim 13, the distal end of the support frame in the expanded deployed configuration having a circular profile including a center radially offset from the longitudinal axis.

20. The catheter tip of claim 13, wherein the support frame further comprises one or more connector ribs extending from a ring member connected to a proximal end of the support frame, the connector ribs diverging from the ring member in an offset plane that is angled relative to an offset plane of the hoop ribs.

Images