Method and system for reducing limb ischemia

Abstract

Devices and methods are provided for minimizing and / or preventing limb ischemia, such as for minimizing and / or preventing limb ischemia resulting from possibly occluding blood vessels when a medical device is inserted into the vasculature of a patient. The device may include a tubular member and one or more radially expandable features (such as balloons and / or hydrostatic bones, etc.) configured to expand at a target location to allow blood to flow around and / or through the radially expandable features.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to US 63 / 340,358 filed on May 10, 2022, the entire contents of which are incorporated herein by reference in their entirety. Technical Field

[0003] The present disclosure relates to methods, devices and systems for preventing limb ischemia, such as limb ischemia caused by the use of mechanical circulatory support devices. Background Art

[0004] Limb ischemia is a rapid and sudden decrease in limb perfusion that often threatens limb viability. It can occur as a result of blood obstruction due to indwelling sheaths and / or catheters, partial occlusions (e.g., atherosclerotic stenosis), and / or persistent occlusions due to small vessels and / or large sheaths. It can also occur as a result of occlusive problems.

[0005] Limb ischemia is associated with mortality, and some literature suggests that the rate of limb ischemia may be high. Therefore, in addition to negatively affecting patients, it may also have a negative impact on ongoing clinical trials. Summary of the invention

[0006] In various aspects, a device may be provided. The device may include a tubular member. The device may include one or more radially expandable features disposed on an outer surface of the tubular member. The one or more radially expandable features may be configured to selectively expand from a contracted configuration to an expanded configuration to allow blood in a patient's blood vessel to flow around and / or through the one or more radially expandable features from a point upstream of the one or more radially expandable features to a point downstream of the one or more radially expandable features.

[0007] The one or more radially expandable features may include one or more balloons. The one or more radially expandable features may extend along a portion of the length of the tubular member. Each radially expandable feature may have the same axial length. In some embodiments, at least one of the one or more radially expandable features may have a different axial length than another of the one or more radially expandable features.

[0008] The one or more radially expandable features may include a plurality of radially expandable features. Each radially expandable feature may be circumferentially spaced apart from an adjacent radially expandable feature by the same distance. In certain embodiments, each of the plurality of radially expandable features may be circumferentially spaced apart from an adjacent radially expandable feature. The circumferential separation distance of adjacent radially expandable features of a first adjacent pair may be different from the circumferential separation distance of adjacent radially expandable features of a second adjacent pair.

[0009] The central axis of each radially expandable feature may be parallel to the central axis of the tubular member. At least one radially expandable feature may be arranged on the outer surface of the tubular member in a spiral pattern. At least one radially expandable feature may have an elliptical or circular cross-sectional shape. At least one radially expandable feature may have a polygonal cross-sectional shape.

[0010] Each radially expandable feature may be fluidly connected to a fluid source. Each radially expandable feature may be operably connected to a connector. The radially expandable features may include a hydrostatic skeleton.

[0011] In various aspects, a device may be provided. The device may include a tubular member, and may include a hydrostatic bone coupled to the tubular member. The hydrostatic bone may be configured to selectively expand ("expand") or contract ("compress"). The hydrostatic bone may be configured to expand from a contracted configuration to an expanded configuration to create at least a first channel to allow blood to flow through the first channel from a point upstream of the hydrostatic bone to a point downstream of the hydrostatic bone.

[0012] The hydrostatic bone can be configured to selectively expand or contract to create at least a first channel and a second channel. The cross-sectional area of ​​the first channel can be the same as the cross-sectional area of ​​the second channel. The cross-sectional area of ​​the first channel can be different from the cross-sectional area of ​​the second channel. The cross-sectional area of ​​the first channel can be controlled separately from the cross-sectional area of ​​the second channel. The tubular member can be configured to slidably receive the second tubular member. The device can include a valve located at the proximal end of the tubular member, the valve being operably connected to the second channel.

[0013] The hydrostatic skeleton may extend completely around the circumference of the tubular member. The hydrostatic skeleton may extend only partially around the circumference of the tubular member. The hydrostatic skeleton may be coupled to the distal end of the tubular member. At least a portion of the hydrostatic skeleton may extend along the axial length of the tubular member. When the hydrostatic skeleton expands, the diameter of the first channel may increase. The hydrostatic skeleton may include a plurality of annular rings.

[0014] In various aspects, a method may be provided. The method may include positioning a tubular member within a blood vessel, the tubular member having an outer surface and at least one radially expandable member coupled to the outer surface. The method may include expanding at least one radially expandable feature from a collapsed configuration to an expanded configuration to allow blood to flow around and / or through (e.g., through an opening or channel created by the feature) the at least one radially expandable feature from a point upstream of the at least one radially expandable feature to a point downstream of the at least one radially expandable feature.

[0015] The step of expanding the at least one radially expandable feature may include expanding a portion of the blood vessel surrounding the at least one radially expandable feature.

[0016] The step of expanding from the collapsed configuration to the expanded configuration may include simultaneously expanding all of the plurality of radially expandable features. The step of expanding from the collapsed configuration to the expanded configuration may include selectively expanding less than all of the plurality of radially expandable features.

[0017] The step of expanding from the contracted configuration to the expanded configuration may occur automatically based on the received information. The received information may be a determination that an ischemic event is occurring or may be occurring. The received information may be a value from a sensor.

[0018] The method may include measuring pressure within the vessel, such as upstream and / or downstream of the radially expandable feature, etc. At least one radially expandable feature may include a balloon. At least one radially expandable feature may include a hydrostatic bone. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the general description of the invention given above and the detailed description of the embodiments given below, serve to explain the principles of the invention.

[0020] Figure 1A is a schematic diagram of the device positioned within a blood vessel.

[0021] Figure 1B A cross section of the device in Figure 1 is shown.

[0022] Figure 1C is a cross-sectional view of a device according to another embodiment of the present disclosure.

[0023] Figure 2A is a schematic diagram of the device positioned within a blood vessel.

[0024] Figure 2B-2C yes Figure 2A Schematic diagram of a cross section of various embodiments of the device.

[0025] Figure 2D is a schematic diagram of another embodiment of a device positioned within a blood vessel.

[0026] Figure 2E-2F yes Figure 2D Schematic diagram of a cross section of various embodiments of the device.

[0027] Figure 2G is a schematic diagram of another embodiment of a device positioned within a blood vessel.

[0028] Figure 3is a flow chart of the method. DETAILED DESCRIPTION

[0029] The following description and accompanying drawings merely illustrate the principles of the present invention. It will therefore be appreciated that a person skilled in the art will be able to design various arrangements which, although not explicitly described or shown herein, embody the principles of the present invention and are included within its scope. In addition, all examples cited herein are primarily for illustrative purposes to help the reader understand the principles of the present invention and the concepts contributed by the inventors to advancing technology, and should be understood as not being limited to these specifically cited examples and conditions. In addition, unless otherwise specified (e.g., "otherwise" or "or alternatively"), the word "or" used herein refers to a non-exclusive or. Similarly, the various embodiments described herein are not necessarily mutually exclusive, as some embodiments may be combined with one or more other embodiments to form new embodiments.

[0030] Many innovative teachings of the present application will be described with particular reference to currently preferred exemplary embodiments. However, it should be understood that such embodiments only provide some examples of many advantageous uses of the innovative teachings herein. In general, the statements in the present application specification do not necessarily limit any of the various claimed inventions. In addition, some statements may be applicable to some inventive features, but not to other features. Those skilled in the art and those taught by this article will appreciate that the present invention is also applicable to various other technical fields or embodiments.

[0031] Limb ischemia is a rapid and sudden decrease in perfusion to a patient's limb and can occur due to obstruction of blood flow due to indwelling sheaths and / or catheters, partial occlusions (e.g., atherosclerotic stenosis), and / or continuous occlusions due to small vessels and / or large sheaths. Limb ischemia can also occur due to locking devices.

[0032] In some cases, in order to solve limb ischemia, a small diameter catheter can be inserted at the distal end to provide antegrade blood flow to the ischemic limb. For example, the catheter can be inserted into the dorsalis pedis artery or the posterior tibial artery. As will be appreciated, antegrade blood flow can be introduced at any appropriate time (for example, at the time of initial ECMO cannulation, or when a mechanical circulatory support device is implanted, or at a later time, such as after ischemia is found). In some cases, conventional solutions may not be available for all patients. For example, some patients may not have a large enough dorsalis pedis artery or posterior tibial artery for catheter introduction.

[0033] The inventors have recognized that when ischemic events are quickly identified and resolved, there may be better patient outcomes. The inventors have also recognized the benefits of promoting and providing distal limb perfusion to patients with arterial occlusions by expanding the vasculature surrounding at least a portion of a fully introduced cannula (e.g., an introducer sheath). For example, as described herein, expanding the vasculature surrounding at least a portion of a cannula may allow blood flow (e.g., retrograde blood flow) to flow around and alongside the cannula. In this regard, the disclosed devices and methods may address the unmet needs of currently existing distal limb perfusion technologies. The disclosed devices and methods may also reduce the number of insertion points in a patient's body, which may reduce the risk of infection, sepsis, bleeding, hematoma, ischemia, and pseudoaneurysm.

[0034] In various aspects, devices and methods can be provided for promoting and providing distal limb perfusion and reducing limb ischemia. Figure 1A , the device 100 may include a tubular member 110 that may be inserted into the vasculature of a patient. Figure 1A As shown, the tubular member can be designed to be inserted at the access point 20, through the skin 22, and into the blood vessel 10. In some embodiments, the tubular member can be a sheath, cannula and / or catheter, although other suitable tubular members can also be used. The tubular member can be composed of any suitable material, such as nickel-titanium alloy, medical grade polymers (such as polyurethane, etc.), and / or combinations thereof. In other embodiments, the tubular member can be made of other suitable materials.

[0035] As described herein, the tubular member can be configured to selectively expand at least a portion of the vasculature of the patient surrounding the tubular member. Figures 1A-1C As shown, the tubular member may include one or more features 120 configured to expand radially to move at least a portion 12 of the blood vessel 10 away from the tubular member, thereby allowing blood to flow 140 between the tubular member and the blood vessel from a point 141 upstream of the feature to a point 142 downstream of the feature. For example, in some embodiments, the feature may have a collapsed configuration (such as when the tubular member is inserted into a patient's body, etc.) and an expanded configuration (such as when the tubular member is inserted into a patient's body, etc.). Figure 1A (e.g., the case shown, where one or more features are expanded to move a portion 12 of the vessel away from the sheath). As will be appreciated, when the features are in the expanded configuration, the diameter of the tubular member (e.g., the distance from the center of the tubular member to the outermost portion of the expandable features) is greater than the diameter of the tubular member when the features are in the collapsed configuration.

[0036] The features may be made of any suitable material, such as nickel-titanium alloys, medical grade polymers (such as polyurethane), or other suitable materials, etc. As will be appreciated, the features may be made of expandable materials. In some embodiments, the features may each include a balloon that may be expandable, such as via controlled addition of fluid from a fluid source 132. In some embodiments, the device may include a controller 130 that selectively expands and / or contracts the features by adding and / or removing fluid from the features. In some embodiments, the fluid may be saline, although other suitable fluids such as gases, etc. may also be used. In some embodiments, the fluid may pass through one or more lumens in the tubular member (not shown). In this regard, the fluid source may be fluidly coupled to the features via one or more lumens in the tubular member.

[0037] like Figures 1A-1C As shown, the tubular member may include a plurality of features 120 extending around the periphery of the tubular member. Figure 1B , the features may be configured such that each feature 120 may be disposed on the outer surface 112 of the tubular member 110. The inner surface 114 of the tubular member may define a cavity 116 extending therethrough.

[0038] The number of features can vary. Figure 1B As shown, the device may have three features. Figure 1C In the embodiment of the present invention, the device is shown as having five features. However, any number of features may be present. For example, in some embodiments, the tubular member may have one or more expandable features.

[0039] In different embodiments, the arrangement of radially expandable features may be different. In certain embodiments, one or more radially expandable features may extend along a portion of the axial length 122 of the tubular member. In certain embodiments, each radially expandable feature may have the same axial length. In certain embodiments, the radially expandable features may not be the same. For example, at least one radially expandable feature may have a different axial length than another. In another example, at least one radially expandable feature may have a different diameter than another radially expandable feature. In certain embodiments, the central axis of each radially expandable feature may be parallel to the central axis of the tubular member. In certain embodiments, the radially expandable features may be arranged in a spiral pattern (or a partial spiral pattern) on the outer surface of the tubular member.

[0040] As will be appreciated, in certain embodiments, the radially expanding features may be spaced apart along the axial length of the tubular member, rather than just circumferentially spaced apart from one another.

[0041] The device can include a plurality of radially expandable features. These features can be arranged in various ways relative to each other. For example, each radially expandable feature can be circumferentially separated from adjacent radially expandable features by the same distance. In some embodiments, the circumferential separation distance of adjacent pairs in a plurality of adjacent radially expandable features is different from the circumferential separation distance of different adjacent pairs in a plurality of adjacent radially expandable features.

[0042] The shapes of the radially expandable features can be different. The radially expandable features can have an elliptical or circular cross-sectional shape, a polygonal cross-sectional shape, or a combination thereof. Each feature can have the same cross-sectional shape. In certain embodiments, at least one feature has a different cross-sectional shape than another feature.

[0043] As will be appreciated, the features can be attached to the tubular member in any suitable manner. For example, the features can be glued, bonded or otherwise affixed thereto. In these embodiments, the features can be non-removable from the tubular member. As will be appreciated, in some embodiments, the features can also be integrally formed with the tubular member. In other embodiments, the features can be configured to be attached to the tubular member before the tubular member is inserted into a patient's blood vessel (e.g., by a clinician).

[0044] In certain embodiments, Figures 2A-2C As shown, the radially expanding feature can be configured as a hydrostatic skeleton. Figure 2A In certain embodiments, the apparatus 200 may include a tubular member 110 having a hydrostatic bone 220 coupled to the tubular member. As will be appreciated, the hydrostatic bone may be attached in a manner similar to the features described herein. The hydrostatic bone may be comprised of any suitable flexible material, such as polyurethane or Teflon, etc., that may expand to a certain pressure corresponding to a particular outer diameter. As will be appreciated, in view of the above, the hydrostatic bone may be connected to a fluid source and controller that may selectively add fluid and / or remove fluid from the bone, thereby selectively expanding the hydrostatic bone to allow blood to flow around the tubular member. As in the above examples, the hydrostatic bone may have a contracted and expanded configuration.

[0045] In some embodiments, the hydrostatic bone can be configured to be selectively inflated or deflated to create at least the first channel 222 (see Figure 2B and Figure 2E), thereby allowing blood to flow through the first channel 140 from a point 141 located upstream of the hydrostatic bone to a point 142 located downstream of the hydrostatic bone. As will be appreciated, similar to the above example, expansion of the hydrostatic bone can also increase the diameter of the patient's vasculature surrounding the expanded bone.

[0046] In some embodiments, the maximum diameter (e.g., maximum effective diameter, etc.) of the first channel can be 1 Fr, 3 Fr, 5 Fr, 7 Fr, 9 Fr, 10 Fr, 11 Fr, 12 Fr, 13 Fr, 15 Fr, 17 Fr, 20 Fr, or 23 Fr. In some embodiments, the hydrostatic bone can be configured to selectively expand or contract to create at least the first channel 222, and optionally the second channel 223 (see Figure 2C and Figure 2F ). In some embodiments, the maximum diameter of the second channel (e.g., maximum effective diameter, etc.) can be 1 Fr, 3 Fr, 5 Fr, 7 Fr, 9 Fr, 10 Fr, 11 Fr, 12 Fr, 13 Fr, 15 Fr, 17 Fr, 20 Fr, or 23 Fr. As will be appreciated, the first channel and / or the second channel can have any suitable diameter. It will be further appreciated that the hydrostatic bone can be formed to have other suitable numbers of channels. In embodiments having more than one channel, the effective diameter of the first channel and the second channel can be the same, although the diameters can also be different. As will be further appreciated, the first channel and / or the second channel can have any suitable shape.

[0047] When initially deployed and in a collapsed configuration, the hydrostatic bone will have a minimum cross-section. When expanded and in an expanded configuration, the hydrostatic bone may have a cross-sectional area that is no greater than the cross-sectional area of ​​the tubular member. In certain embodiments, the hydrostatic bone may have a cross-sectional area that is smaller than the cross-sectional area of ​​the tubular member. Figure 2B , shows a relatively small hydrostatic bone having a single channel (e.g., only the first channel 222). In other embodiments, the hydrostatic bone can have the same diameter as the tubular member. In still other embodiments, such as Figure 2D-2F As shown, the hydrostatic bone can have a cross-sectional area greater than that of the tubular member. Figure 2D and 2E , a hydrostatic bone having a larger cross-sectional area relative to the tubular member is shown.

[0048] refer to Figure 2C, the outer surface 112 of the tubular member 110 may form a portion of the first channel 222. Also, as seen, in some embodiments, the bone may include a plurality of channels, including, for example, a first channel 222 and a second channel 223. In some embodiments, the bone may include a separator 225 so that at least two channels can be controlled separately. As will be appreciated, in some embodiments, the separator may include a membrane separating the first channel and the second channel. In other embodiments, the separator may be part of the bone and may itself be expandable. In some embodiments, the cross-sectional areas of the first channel and the second channel may be the same. In some embodiments, the cross-sectional areas of the first channel and the second channel may be different.

[0049] In certain embodiments, the diameter of the first channel can increase as the hydrostatic bone expands.

[0050] In certain embodiments, the cross-sectional area of ​​the first channel can be controlled separately from the cross-sectional area of ​​the second channel. Figure 2C As shown, a membrane or separator 225 can fluidically separate the portion of the bone surrounding the first channel 222 from the portion surrounding the second channel 223, thereby allowing each portion to be controlled separately. In some embodiments, the device simply has two separate hydrostatic bones, each with a single channel.

[0051] In some embodiments, the tubular member 200 can be configured to slidably receive an additional tubular member 230 (such as a catheter, etc.). This can be received, for example, through a channel or cavity 202 (see Figure 2A In some embodiments, the maximum diameter (eg, maximum effective diameter, etc.) of the channel or cavity 202 may be 9 Fr, 10 Fr, 11 Fr, 12 Fr, 13 Fr, 15 Fr, 17 Fr, 20 Fr, or 23 Fr.

[0052] In some embodiments, the device can include a valve 212 at the proximal end 118 of the tubular member 110. The valve can be operably coupled to the channel or cavity 202. The valve can be configured to receive an additional tubular member 230. In some embodiments, the tubular member 110 and the additional tubular member 230 can be integrally formed.

[0053] The hydrostatic bone can be coupled to the distal end of the tubular member at or near the distal end. In some embodiments, the hydrostatic bone can extend completely around the periphery of the tubular member. In some embodiments, the hydrostatic bone can extend only partially around the periphery of the tubular member.

[0054] In some embodiments, there may be only a single hydrostatic bone. In some embodiments, there may be multiple hydrostatic bones.

[0055] refer to Figure 2D , it can be seen that at least a portion of the hydrostatic skeleton 220 can extend along the axial length 122 of the tubular member.

[0056] In some embodiments, the hydrostatic bone 220 can include a plurality of axially spaced rings 240, each of which can be in contact with the tubular member 110. In some embodiments, each ring can be individually controlled (e.g., selectively expanded via a fluid). In some embodiments, the entire bone is controlled as a collective unit. In some embodiments, two or more rings can be separated by a connector 241 that can allow fluid to pass from one ring to a connected ring. In some embodiments, the connector can also maintain a specified distance between adjacent rings.

[0057] In certain embodiments, the rings may form a single channel extending through the hydrostatic bone (see e.g. Figure 2E ). In some embodiments, such as in Figure 2F As can be seen, one or more rings may define two channels.

[0058] Although shown and described as allowing blood to flow through the channels of the hydrostatic bone, it will be appreciated that the channels can be configured to allow other devices to pass through. Figure 2G , the hydrostatic bone can be configured to allow an additional tubular member 250 to extend at least partially through the hydrostatic bone. In some embodiments, the tubular member 250 can extend through the entire hydrostatic bone. The additional tubular member can extend through one or more rings 240 of the hydrostatic bone. In some embodiments, the tubular member 250 can extend through only one of the channels of the hydrostatic bone.

[0059] In various aspects, the devices used herein can be used to reduce and / or prevent limb ischemia, as depicted by the methods provided herein. Figure 3 , method 300 may include positioning a tubular member 310 within a blood vessel. In certain embodiments, the tubular member may allow passage of one or more medical devices, such as a mechanical circulatory support device for treating a patient, etc. As will be appreciated, in certain circumstances, the tubular member may reduce and / or prevent blood flow through the blood vessel in at least a portion of the blood vessel, which may result in ischemia.

[0060] Thus, the method may also include expanding 320 the at least one radially expandable feature from a contracted configuration to an expanded configuration to expand the portion of the vessel and allow blood to flow around or through the at least one radially expandable feature from a point upstream of the at least one radially expandable feature to a point downstream of the at least one radially expandable feature. In certain embodiments, the expandable feature may include a hydrostatic skeleton, and the method may include allowing blood to flow through one or more channels of the expanded hydrostatic skeleton.

[0061] In certain embodiments, expanding from the collapsed configuration to the expanded configuration may include simultaneously expanding 322 all of the plurality of radially expandable features. Expanding from the collapsed configuration to the expanded configuration may also include selectively expanding 324 less than all of the plurality of radially expandable features.

[0062] In certain embodiments, expanding the at least one radially expandable feature may include inflating the at least one expandable feature by providing a fluid from a fluid source to the expandable feature.

[0063] In some embodiments, expanding from the collapsed configuration to the expanded configuration may include receiving 326 information and then, based on the received information, automatically expanding 328 from the collapsed configuration to the expanded configuration. Figure 1A , the disclosed device may include one or more sensors 102 (such as one or more pressure sensors positioned within a vessel along the device, etc.). In certain embodiments, based on information received from the sensors, the method may include automatically expanding the feature from a contracted configuration to an expanded configuration. In certain embodiments, one or more processors may determine that an ischemic event is occurring or may be occurring based on values ​​from one or more sensors (or from another device, such as a monitoring patch or mechanical circulatory support device, etc.), and based on this determination, automatically expand one or more features from a contracted configuration to an expanded configuration. As will be appreciated, the method may include collecting the necessary data to allow such automatic corrections to occur, such as measuring 330 pressure within the vessel, such as upstream and / or downstream of the radially expandable feature.

[0064] After completing the medical procedure or support (e.g., by a device inserted into the patient's vasculature via the tubular member), the method may include removing the tubular member from the patient. In this regard, the method may then include deflation 340 of at least one expandable feature such that the at least one feature returns to a collapsed state. This step may also include ensuring that all radially expandable features are in a collapsed configuration. The method may ultimately include removing 350 the tubular member from the blood vessel and closing the access point.

[0065] Embodiments of the present disclosure are described in detail in the drawings, where similar reference numbers identify similar or identical elements. It should be understood that the disclosed embodiments are merely disclosed examples and can be embodied in various forms. Well-known functions or structures are not described in detail to avoid obscuring the present disclosure with unnecessary detailed descriptions. Therefore, the specific structural and functional details disclosed herein should not be interpreted as restrictive, but only as the basis for the claims, and as a representative basis, teaching those skilled in the art to use the present disclosure in a variety of ways with substantially any appropriate detailed structure.

[0066] Although various embodiments are shown and described in detail herein, these embodiments incorporate the teachings of the present invention, those skilled in the art can easily design many other different embodiments, which still incorporate these teachings. Therefore, although the above content is directed to various embodiments of the present invention, other and further embodiments of the present invention can be designed without departing from its basic scope.

Claims

1. A device comprising: Tubular components; as well as One or more radially expandable features are arranged on the outer surface of the tubular member, and the one or more radially expandable features are configured to selectively expand from a contracted configuration to an expanded configuration to allow blood within a patient's blood vessel to flow around and / or through the one or more radially expandable features from a point upstream of the one or more radially expandable features to a point downstream of the one or more radially expandable features.

2. A device according to claim 1, wherein the one or more radially expandable features include one or more balloons.

3. The device of claim 1, wherein the one or more radially expandable features extend along a portion of the length of the tubular member.

4. The device of claim 1, wherein each radially expandable feature has the same axial length.

5. The device of claim 1, wherein at least one of the one or more radially expandable features has a different axial length than another of the one or more radially expandable features.

6. The device of claim 1, wherein the one or more radially expandable features comprises a plurality of radially expandable features.

7. The device of claim 6, wherein each of the plurality of radially expandable features is circumferentially spaced apart from adjacent radially expandable features by the same distance.

8. A device according to claim 6, wherein each of the plurality of radially expandable features is circumferentially separated from an adjacent radially expandable feature, and wherein the circumferential separation distance of the plurality of adjacent radially expandable features of a first adjacent pair is different from the circumferential separation distance of the plurality of adjacent radially expandable features of a second adjacent pair.

9. The device of claim 1, wherein the central axis of each radially expandable feature is parallel to the central axis of the tubular member.

10. The device of claim 1, wherein at least one radially expandable feature is arranged in a helical pattern on the outer surface of the tubular member.

11. The device of claim 1, wherein at least one radially expandable feature has an elliptical or circular cross-sectional shape.

12. The device of claim 1, wherein at least one radially expandable feature has a polygonal cross-sectional shape.

13. The device of claim 1, wherein each of the at least one radially expandable feature is fluidly connected to a fluid source.

14. The device of claim 1, wherein each of the at least one radially expandable feature is operably connected to a connector.

15. The device of claim 1, wherein the at least one radially expandable feature comprises a hydrostatic bone.

16. An apparatus comprising: Tubular components; as well as A hydrostatic bone coupled to the tubular member, the hydrostatic bone configured to selectively expand from a contracted configuration to an expanded configuration to create at least a first passageway to allow blood to flow through the first passageway from a point upstream of the hydrostatic bone to a point downstream of the hydrostatic bone.

17. The apparatus of claim 16, wherein the hydrostatic bone is configured to selectively expand or contract to create at least the first and second channels.

18. The device of claim 17, wherein the cross-sectional area of ​​the first passage is the same as the cross-sectional area of ​​the second passage.

19. The device of claim 17, wherein the cross-sectional area of ​​the first passage is different from the cross-sectional area of ​​the second passage.

20. The device of claim 17, wherein a cross-sectional area of ​​the first passage is controlled separately from a cross-sectional area of ​​the second passage.

21. The device of claim 17, wherein the tubular member is configured to slidably receive a second tubular member.

22. The device of claim 17, further comprising a valve at the proximal end of the tubular member, the valve operably coupled to the second passageway.

23. The apparatus of claim 17, wherein said hydrostatic skeleton extends completely around the circumference of said tubular member.

24. The apparatus of claim 17, wherein said hydrostatic bone extends only partially around a circumference of said tubular member.

25. The apparatus of claim 17, wherein the hydrostatic bone is coupled to a distal end of the tubular member.

26. The apparatus of claim 17, wherein at least a portion of said hydrostatic bone extends along an axial length of said tubular member.

27. The device of claim 17, wherein a diameter of said first channel increases when said hydrostatic bone expands.

28. The apparatus of claim 17, wherein said hydrostatic skeleton comprises a plurality of annular rings.

29. A method comprising: positioning a tubular member within a blood vessel, the tubular member having an outer surface and at least one radially expandable member coupled to the outer surface; The at least one radially expandable feature is expanded from a contracted configuration to an expanded configuration to allow blood to flow around and / or through the at least one radially expandable feature from a point upstream of the at least one radially expandable feature to a point downstream of the at least one radially expandable feature.

30. The method of claim 29, wherein the step of expanding the at least one radially expandable feature comprises expanding a portion of the blood vessel surrounding the at least one radially expandable feature.

31. The method of claim 29, wherein expanding the at least one radially expandable feature from a contracted configuration to an expanded configuration comprises simultaneously expanding all of the plurality of radially expandable features.

32. The method of claim 29, wherein expanding the at least one radially expandable feature from a contracted configuration to an expanded configuration comprises selectively expanding less than all of the plurality of radially expandable features.

33. The method of claim 29, wherein expanding the at least one radially expandable feature from the contracted configuration to the expanded configuration occurs automatically based on the received information.

34. The method of claim 33, wherein the received information is a determination that an ischemic event is occurring or may be occurring.

35. The method of claim 33, wherein the received information is a value from a sensor.

36. The method of claim 29, further comprising measuring pressure within the blood vessel.

37. The method of claim 29, wherein the location is upstream of the one or more radially expandable features.

38. The method of claim 29, wherein the location is downstream of the one or more radially expandable features.

39. The method of claim 29, wherein the at least one radially expandable feature comprises a balloon.

40. The method of claim 29, wherein the at least one radially expandable feature comprises a hydrostatic bone.

Images