Extraction device for removing clots

Abstract

Extraction catheters for removing clot material from a patient, systems including these catheters, and methods of making and using these extraction catheters may be configured to remove clot material in a long, continuous strip, which prevents smaller clot fragments from being released back into the vessel. Also described herein are blood collection devices that may allow for safe and easy reperfusion of collected blood.

Description

[0001] Priority claim

[0002] This patent application claims priority to U.S. Provisional Patent Application No. 63 / 334,075, filed on April 22, 2022, entitled “ASPIRATION APPARATUSES FOR CLOT REMOVAL,” which is incorporated herein by reference in its entirety.

[0003] Incorporated by Reference

[0004] All publications and patent applications mentioned in this specification are herein incorporated by reference in their entirety to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference.

[0005] background

[0006] Devices and methods for removing unwanted tissue (e.g., thrombus, atherosclerosis, fluid, polyps, cysts, or other obstructive material) from a body cavity (e.g., a blood vessel, ureter, bile duct, or fallopian tube) can use aspiration to draw the unwanted material into a collection device for removal from the body. In particular, a variety of catheter devices have been developed for use in intraluminal and intravascular procedures for disrupting and removing obstructive material in blood vessels, such as blood clots, thrombus, atherosclerosis, etc.

[0007] In many cases, the procedure can include breaking up the material (e.g., clotted material), typically by infusing a fluid (saline or thrombolytic agent) into the vessel or treatment site to help break up the clot or tissue into a particle size that can then be extracted through a lumen of a treatment device or using an auxiliary catheter connected to a vacuum / suction source. Depending on the method of breaking up and the consistency of the clot or tissue, the particle size can vary. If the material is not completely broken up, larger particles can accumulate in the catheter and clog the extraction lumen.

[0008] However, these surgeries may result in the release of smaller fragments back into the body, which is undesirable. In addition, larger fragments may still clog the device and require more complex surgery, increasing the risk of complications due to blood loss and prolonged surgery time. Therefore, there is a need to more effectively remove material, such as blood clots, from a vessel or body cavity. In addition, it is desirable to have a device that allows larger particles to be extracted without the need to disrupt the clot material, thereby reducing surgery time. Preferably, such an improved device will have a low profile to enable percutaneous use, and will be flexible and torsionable to enable use in a tortuous cavity. In addition, such a device may preferably be designed to be placed over a guide wire.

[0009] Overview of the Disclosure

[0010] Extraction catheters for removing clot material from patients, systems including these catheters, and methods for making and using these extraction catheters are described herein. In particular, these catheters can be configured to remove clots in longer continuous strips, which prevents smaller clot fragments from being released back into the vasculature, which will be problematic. Apparatus (e.g., device and system, particularly including extraction catheters) and methods described herein can be configured to include an inlet (e.g., opening), which is configured and positioned to produce a buffer flow of fluid, which passes through (and in some cases is opposite to) suction into the catheter laterally through a side-facing extraction opening in a manner that applies a rotational momentum or force (e.g., rotational torque) on the clot when the clot is driven against the distal edge of the extraction opening, causing the clot to be continuously cut into strips that can be simultaneously pulled into the extraction chamber of the catheter. Therefore, these generally distal openings can be referred to as buffer flow openings herein. The buffer flow openings may be openings into the vessel and / or they may be openings for applying fluid through a sub-lumen (e.g., separate from and / or through and / or adjacent to the extraction lumen). The methods and apparatus described herein may be particularly well suited for removing clots from larger vessels, including (but not limited to) pulmonary embolism and thrombectomy, including peripheral thrombectomy.

[0011] Compared with other extraction catheters for removing clots, the extraction catheter described herein provides many advantages. In particular, the methods and devices described herein can be configured to apply an entrained flow of a fluid (e.g., blood or other fluids) that rotates (and / or flips) the clot in the vessel and drives the clot against the proximal edge of the extraction opening without violently destroying the clot. Unlike other devices that provide a "jet stream" of a fluid (including blood) intended to destroy and decompose a clot, the device described herein, and in particular the buffer flow opening, is configured to prevent such destruction and decomposition of clot material. In particular, the features of the buffer flow opening described herein define a specific parameter range that results in a gentler rotational motion on the clot that can result in a strip of clot material being cut from the clot. These ranges can include at least some of the buffer flow openings relative to the longitudinal position of the extraction chamber, the size of the buffer flow opening relative to the extraction chamber, the radial position of the buffer flow opening relative to the extraction opening, and / or the number of buffer flow openings. As will be described herein, outside of these ranges, the extraction catheter may not operate effectively, may not provide rotational force, may not cut a strip of clotted material as described herein, and / or may cause clotted material to become clogged or "lollypop" in the extraction opening. The buffered flow openings described herein may also be optimized to minimize blood loss during an extraction procedure and / or to increase the rate at which clotted material is removed.

[0012] For example, an extraction catheter (e.g., a suction catheter) having one or more buffer flow openings is described herein, wherein one or more of the buffer flow openings are located distally of the center (along the longitudinal axis of the distal end region). Typically, the buffer flow opening can be radially opposite to the extraction opening (e.g., radially offset from the longitudinal midline of the extraction opening by more than 90 degrees, such as greater than 100 degrees, greater than 110 degrees, greater than 120 degrees, etc.). Typically, the buffer flow opening can include at least one buffer flow opening that is positioned opposite to the extraction opening and distally of the longitudinal midpoint of the extraction opening. In some examples, the buffer flow opening can have a geometric center of the sum of all buffer flow openings within + / - 20% of the center of the longitudinal midpoint of the extraction opening (and specifically, the geometric center can be offset distally from the longitudinal midpoint of the extraction opening).

[0013] For example, a suction catheter device may include: an elongated body having a suction chamber; a distal region extending from the elongated body, the distal region having an extraction opening extending along the length of a lateral side of the distal region; and one or more buffer flow openings passing through a side of the distal region opposite to the extraction opening, wherein the one or more buffer flow openings collectively have a geometric center along the length of the lateral side of the distal region that is within + / - 20% of the longitudinal center of the extraction opening, wherein the one or more buffer flow openings are configured to apply rotation to the clot material (e.g., transfer rotational momentum) to drive the clot material against the proximal edge of the extraction opening, thereby cutting an elongated strip from the clot material and entraining the elongated strip so that the elongated strip is pulled proximally and downward within the suction chamber.

[0014] A suction catheter device may include: an elongated body having a suction chamber; a distal region extending from the elongated body, the distal region having an extraction opening extending along the length of a side of the distal region; and one or more buffer flow openings, the one or more buffer flow openings passing through a side of the distal region opposite to the extraction opening and / or through the distal end of the distal region, wherein the one or more buffer flow openings collectively have a geometric center along the length of the side of the distal region, the geometric center being distal to the longitudinal center of the extraction opening, wherein the one or more buffer flow openings are configured to impart rotation (e.g., impart angular momentum) to the clot material to drive the clot material against the proximal edge of the extraction opening, thereby cutting an elongated strip from the clot material and entraining the elongated strip so that the elongated strip is pulled proximally and downward within the suction chamber.

[0015] A suction catheter device may include: an elongated body having a suction chamber; a distal region extending from the elongated body, the distal region having an extraction opening extending along the length of a side of the distal region; and a plurality of buffer flow openings ranging from 2 to 20 (e.g., between 2 to 16, between 2 to 10, between 2 to 8, etc.) through a side of the distal region opposite to the extraction opening, wherein the plurality of buffer flow openings together have a geometric center along the length of the side of the distal region, the geometric center being located at the longitudinal center of the extraction opening or distal to the longitudinal center of the extraction opening, wherein the plurality of buffer flow openings are configured to impart rotation (e.g., impart angular momentum) to the clot material to drive the clot material against the proximal edge of the extraction opening to cut an elongated strip from the clot material and entrain the elongated strip so that the elongated strip is pulled proximally and downward within the suction chamber.

[0016] In some examples, a suction catheter device includes: an elongated body having a suction chamber; a distal region extending from the elongated body, the distal region having an extraction opening extending along the length of a side of the distal region; and a plurality of buffer flow openings between 2-20 (e.g., between 2-16, between 2-10, between 2-8, etc.), the plurality of buffer flow openings passing through a side of the distal region opposite to the extraction opening, wherein the plurality of buffer flow openings collectively have a geometric center along the length of the side of the distal region, the geometric center being located at or distal to the longitudinal center of the extraction opening, wherein a ratio between an area of ​​the extraction opening and a combined area of ​​the plurality of buffer flow openings is between 12:1 and 14:1, and further wherein the plurality of buffer flow openings are configured to impart rotation (e.g., angular momentum) to the clot material to drive the clot material against a proximal edge of the extraction opening to cut an elongated strip from the clot material and entrain the elongated strip so that the elongated strip is pulled proximally and downward within the suction chamber.

[0017] In any of these devices, the distal region may be configured to be coupled to a distal end of the elongate body.The distal region may include an extraction opening and one or more buffer flow openings.

[0018] Typically, the common geometric center of one or more buffer flow openings can be within + / - 10% of the longitudinal center of the extraction opening, and in particular can be distal to the longitudinal center of the extraction opening. For example, the common geometric center of one or more buffer flow openings can be located at the longitudinal center of the extraction opening or distal to the longitudinal center. In some examples, the buffer flow openings can include at least one opening distal to the longitudinal center. For example, at least one of the one or more buffer flow openings can be distal to the longitudinal center of the extraction opening.

[0019] Any number of buffer flow openings may be used, including one, two, three, four, five, six, seven, eight, etc. For example, the one or more buffer flow openings may include between 2-8 buffer flow openings.

[0020] Any of the devices described herein may include a surface extending from a catheter and / or from a distal region, which surface can prevent the blockage of the buffer flow opening. The surface may be configured as a projection and / or a shield. For example, any of these devices may include a shield, which extends from an outer surface of an elongated body opposite to the extraction opening and at the distal end of the buffer flow opening, wherein the shield is configured to prevent clot material from entering the buffer flow opening. In some cases, the shield may be expandable, inflatable, etc. In some cases, the shield or projection may be a part of a cavity (e.g., a guide cavity or a diagnostic catheter cavity, etc.). In some cases, the shield or projection may be configured to prevent the clot (at the distal end) from extending backward and entering the buffer flow opening. In some examples, the same or different shields may be configured to prevent the buffer flow opening from being attracted to the wall of the cavity (e.g., the wall of the vessel).

[0021] As described above, generally, the buffer flow opening can be positioned relative to the extraction opening in the radial direction. In some cases, the buffer flow opening can be rotated between 90 and 180 degrees (e.g., between 90 and 145 degrees, between 90 and 180 degrees, etc.) from the longitudinal centerline passing through the extraction opening.

[0022] Any of these devices may include a guiding cavity or a navigation cavity, which extends along the distal region adjacent to the suction cavity relative to the extraction opening. The guiding cavity or the navigation cavity (collectively referred to as the navigation cavity in this article) can be configured to receive a guide catheter or a guide wire. In some cases, the guiding cavity or the navigation cavity can be configured to receive a diagnostic catheter, which can extend a distal extraction catheter.

[0023] In any of these examples, the buffer flow opening may pass through the navigation cavity and / or be blocked or shielded by the navigation cavity; in some examples, the buffer flow opening may be opened / closed by extending or withdrawing an elongated member (such as a diagnostic catheter) in the cavity. When the diagnostic catheter extends distally to the buffer flow opening, these openings may be partially or completely closed or blocked by the diagnostic catheter, thereby allowing the opening to be "closed" or "opened" by longitudinally repositioning the diagnostic catheter. For example, one or more buffer flow openings may extend through the navigation cavity so that the buffer flow opening may be opened or closed by passing the elongated member through the navigation cavity. Alternatively, in some examples, the buffer flow opening may be configured to be opened regardless of the position of the diagnostic catheter. In any of the devices described herein, the contour of the navigation cavity may be configured to protect the buffer flow openings and prevent them from being blocked or blocked by clot material and / or cavity walls. In some examples, the contour of the navigation cavity may be configured to help guide the fluid flow through the buffer flow opening, for example, so that it can more effectively impart rotation on the clot material in or adjacent to the extraction opening. For example, in some cases, the one or more buffer flow openings may include two or more buffer flow openings disposed on either side of the navigation cavity.

[0024] Any of the devices described herein can be optimized so that the flow through the buffer flow opening is configured to entrain the fluid in the suction chamber downward along the length of the suction chamber and impart rotation (e.g., angular momentum) to the clot material against the proximal / proximal edge of the extraction device. For example, any of these devices (e.g., devices, systems, etc.) can be configured so that the opening surface area of ​​the extraction opening is about 10:1 to 18:1 (e.g., 10:1 to 17:1, 10:1 to 16:1, etc.) compared to the sum of the opening surface areas of the buffer flow openings. For example, in some examples, the ratio between the area of ​​the extraction opening and the combined area of ​​one or more buffer flow openings is between 10:1 and 16:1. In some examples, the ratio between the area of ​​the extraction opening and the combined area of ​​one or more buffer flow openings is between 12:1 and 14:1. Outside these ratios, the device may not operate as efficiently and may take significantly longer to extract the clot.

[0025] Typically, the buffer flow opening can be configured to impart rotation on a clot positioned in or adjacent to the side and / or tapered extraction opening. This angular momentum results in driving the clot material against the proximal edge of the extraction orifice, and thus the clot material can be cut; in particular, it can cut the clot material into relatively long and thin strips while controlling the movement of the clot. In large vessels, this may cause the clot to rotate against the proximal edge of the extraction opening. However, even in smaller vessels, the rotational torque, although not rotating the clot due to the size limitations of the vessel, can instead drive the clot against the extraction opening in a manner similar to the carriage of a typewriter, for example, by axially driving the clot material along the edge of the extraction orifice in a distal to proximal direction, then moving the clot material from the proximal side to the distal side and repeating the cutting from the distal side to the proximal side. This movement can be the result of a combination of the extraction force through the extraction opening and the rotational force (e.g., rotational torque) imparted by the flow from the buffer flow opening, which is repeated until the clot is small enough to pass completely through the extraction cavity.

[0026] As described above, any of these devices may include a displacement projection (e.g., a shroud) extending from an outer surface of the distal region that is configured to displace an outer opening of the one or more buffer flow openings from a wall of a vessel into which the distal region is inserted.

[0027] Typically, the distal region of the device may taper at least over the length of the side of the distal region including the extraction opening. Thus, the proximal outer edge region of the extraction opening against which the clot material is driven and rotated (or flipped) may be larger than the distal edge region, e.g., the extraction opening may be wider at the proximal end than at the distal end.

[0028] Typically, the extraction opening can be reinforced around the periphery of the opening and / or radially around any one or both of the distal ends. For example, the extraction opening may include a reinforced lip area. The extraction opening may be enlarged and / or may include a structural reinforcement (wire, etc.). Therefore, the extraction opening may include a reinforced lip area that surrounds at least the proximal edge of the extraction opening. The reinforcement structure can enhance the lip area of ​​the extraction opening, but the extraction opening can still have a non-damaged outer surface that enables the device to be advanced in the vessel when the extraction orifice is effectively opened without cutting or damaging the vessel wall. Alternatively or additionally, in some embodiments, the extraction orifice can be covered, for example, with an elastic membrane that deflects inwardly and / or radially when extraction is applied and clots enter the hole. In embodiments where the extraction orifice is covered, the extraction force required to expose the extraction orifice is less than the force of entrained fluid through the buffer flow opening.

[0029] Although the extraction opening is generally atraumatic (e.g., configured so as not to cut or obstruct the wall of the vessel), in some examples, the extraction opening includes a cutting edge or surface on at least a proximal edge of the extraction opening, preferably in a lip region separated from the sides of the extraction opening. For example, the extraction opening or at least the proximal region can include a cutting surface that is recessed relative to the outer surface and edge, which can be rounded or atraumatic. Alternatively or additionally, the proximal edge region can be thinner than more lateral and / or distal edge regions of the extraction opening, which can facilitate cutting of clot material driven against the proximal edge region.

[0030] Any of the devices described herein may include one or more sensors for detecting the presence of clot material, including detecting that a clot is still present at the extraction opening and / or within the lumen of the extraction catheter. Any of these devices may include a clot sensor configured to detect clot material in communication with the extraction opening and / or within the distal region.

[0031] In any of the devices described herein, the buffer flow opening may include a distal opening at a distal end of the device. The distal opening may be separate from the buffer flow opening on a side wall of the device.

[0032] For example, the present invention describes an aspiration catheter device comprising: an elongated body having a suction chamber; a distal region extending from the elongated body, the distal region having an extraction opening extending along a tapered length of a side of the distal region; and a plurality of buffer flow openings passing through an outer side surface of the distal region opposite to the extraction opening, wherein at least one of the plurality of buffer flow openings is distal to a longitudinal center of the extraction opening; wherein the extraction opening is configured such that a diameter of the suction chamber at a distal edge of the extraction opening is 40% or more of a diameter of the suction chamber at a proximal edge of the extraction opening, and wherein the plurality of buffer flow openings are configured to form a buffer flow region within the suction chamber opposite to the extraction opening to exert a rotational force on the clot material.

[0033] In any of the devices described herein, a plurality of buffer flow openings may include buffer flow openings between 2-20. Devices described herein may include a navigation channel having a cavity extending in the suction chamber and configured to at least partially block a plurality of buffer flow openings. The plurality of buffer flow openings may be positioned between 60 and 120 degrees with the longitudinal midline passing through the extraction opening. Any of these devices may include a navigation channel including a cavity extending along the distal region adjacent to the suction chamber relative to the extraction opening. In any of these devices, one or more additional buffer flow openings extend through the navigation chamber. A plurality of buffer flow openings may include two or more buffer flow openings arranged on both sides of the navigation chamber.

[0034] The navigation cavity can be configured to have a distal end opening in the suction cavity near the distal end region of the cavity. The ratio between the area of ​​the extraction opening and the combined area of ​​the plurality of buffer flow openings can be between 10:1 and 16:1. In some examples, the ratio between the area of ​​the extraction opening and the combined area of ​​the plurality of buffer flow openings is between 12:1 and 14:1.

[0035] The extraction opening may comprise a reinforced lip region surrounding at least a proximal edge of the extraction opening.The extraction opening may be wider at the proximal end than at the distal end.

[0036] Any of the catheters described herein may include a holdup region at the distal end of the aspiration lumen, distal to the aspiration opening.

[0037] For example, the suction catheter device may include: an elongated body having a suction chamber; a distal region extending from the elongated body, the distal region having an extraction opening extending along a tapered length of a side of the distal region; and a plurality of buffer flow openings passing through a side of the distal region opposite to the extraction opening, wherein at least one of the plurality of buffer flow openings is distal to a longitudinal center of the extraction opening; wherein the extraction opening is configured so that a diameter of the suction chamber at a distal edge of the extraction opening is 40% or more of a diameter of the suction chamber at a proximal edge of the extraction opening, and wherein the plurality of buffer flow openings are configured to form a buffer flow region within the suction chamber opposite to the extraction opening to apply a rotational force (e.g., an angular force) on the clot material to drive the clot material against the proximal edge of the extraction opening to cut a strip from the clot material without breaking the clot material.

[0038] The buffer flow opening can be a hole formed through the side wall of the distal region (distal end), which passes vertically through the distal region between the outer surface and the inner surface, or in some cases, the buffer flow opening can be oriented to slightly (e.g., proximally) guide the flow. Although generally, the apparatus and method described herein can be configured to have a buffer flow opening through the side wall of the distal region of the extraction catheter, any of the methods and apparatus described herein can include an outlet for the buffer flow opening, which is opposite to the extraction opening as described herein, but the entrance to the buffer flow opening can be, for example, closer to the distal end region and more proximally positioned. Generally, these devices can be configured to draw blood from the cavity in which the device is positioned. In some examples, the device can be configured to apply a fluid (e.g., blood, saline, etc.) from an external source. For example, any of the methods and apparatus described herein can be configured to apply a fluid from a fluid line to a buffer flow opening, and the buffer flow opening described herein refers to the outlet of the buffer flow opening (e.g., the inlet can be proximal, included outside the patient, and the outlet can be connected to a fluid line extending proximally).

[0039] In general, methods of using devices such as those described above are described herein. For example, methods are described herein that include causing clot material to roll relative to an extraction opening when removing clot material. In some examples, the method includes a method of removing clot material, the method comprising: positioning an elongated extraction opening of an aspiration catheter to be adjacent to a clot within a lumen of a vessel, wherein the extraction opening extends on a side of a distal region of the aspiration catheter, and further, wherein the aspiration catheter includes one or more buffer flow openings passing through a side of the distal region opposite to the extraction opening; applying suction through a suction cavity of the aspiration catheter to draw the clot and fluid from the extraction opening into the aspiration catheter and drawing the fluid through the one or more buffer flow openings, wherein one or more buffer flow openings are configured relative to the extraction opening so that the fluid flow entering the aspiration catheter imparts a rotational force (e.g., an angular force) on the clot, thereby driving the clot against a proximal edge of the extraction opening, cutting the clot against the proximal edge, and flipping the clot relative to the extraction opening.

[0040] Applying suction can include applying a suction force greater than 10 mmHg (e.g., a difference of approximately 10 mmHg or greater between atmospheric pressure and the pressure within the catheter). Applying suction can include drawing fluid through one or more buffer flow openings, the one or more buffer flow openings collectively having a geometric center at a longitudinal center within 10% of the longitudinal midpoint of the extraction opening or distal to the longitudinal center (e.g., where at least one of the buffer flow openings is positioned distal to the longitudinal center of the extraction opening, etc.). In some examples, applying suction includes drawing fluid through one or more buffer flow openings, the one or more buffer flow openings collectively having a geometric center at a longitudinal midpoint of the extraction opening or distal to the longitudinal midpoint of the extraction opening.

[0041] Any of these methods may include cutting an elongated strip of clot material from the clot as the clot material is driven against the proximal edge of the extraction opening and transforms (e.g., flips or moves / reciprocates axially back and forth) relative to the extraction opening. One or more buffer flow openings may be configured to draw fluid into the aspiration conduit so that the fluid entrains the strip of clot material, which is cut when the clot material is driven against the proximal edge of the extraction opening.

[0042] Applying suction through the aspiration catheter to draw fluid through the one or more buffer flow openings may include entraining the fluid flow down the length of the aspiration lumen without substantially disrupting the cut clot within the aspiration lumen.

[0043] In any of these methods, a clot outside of the extraction catheter may be rolled and / or flipped by flow driven by the buffer flow opening and the extraction opening. Flipping the clot relative to the extraction opening may include rotating the clot within the vessel against the extraction opening of the aspiration catheter.

[0044] As described above, any of these devices and methods may include the use of one or more clot sensing sensors. Accordingly, any of these methods may also include automatically shutting off or reducing suction when a clot is no longer detected adjacent to the extraction opening or within the distal region.

[0045] Also described herein are methods of removing clots in relatively long strands. Unlike previously described systems that may include breaking up clots by using a "jet" of one or more fluids before, during, or after extraction, the methods and devices described herein may be configured to instead remove relatively long lengths of clot strips. For example, the present invention describes a method for removing clot material, which includes: positioning an elongated extraction opening of an aspiration catheter to a clot within a cavity adjacent to a vessel, wherein the extraction opening extends on a side of a distal region of the aspiration catheter, and further wherein the aspiration catheter includes one or more buffer flow openings passing through a side of the distal region opposite to the extraction opening; applying suction through a suction cavity of the aspiration catheter to draw the clot against a proximal edge of the extraction opening of the aspiration catheter, while simultaneously drawing fluid through one or more buffer flow openings so that a strip of clot material is cut off by the proximal edge of the aspiration catheter, wherein the buffer flow openings are configured such that the fluid drawn into the aspiration catheter through the one or more buffer flow openings entrains the strip of clot material to draw the strip of clot material down and proximally along the aspiration catheter without substantially destroying the strip of clot material.

[0046] In any of these methods, positioning the elongated extraction opening can include spacing one or more buffer flow openings away from a wall of the vessel.

[0047] Any of these methods may include applying suction by applying a pressure greater than 10 mmHg (e.g., a difference greater than 10 mmHg relative to the pressure in the atmosphere and / or the vascular). Typically, the buffer flow opening may be positioned or configured so that at least one buffer flow opening (e.g., or at least 2 buffer flow openings, at least 3 buffer flow openings, at least half of the buffer flow opening, etc.) is distal to the longitudinal midpoint of the extraction opening. In some examples, applying suction may include drawing fluid through one or more buffer flow openings, which one or more buffer flow openings have a longitudinal center within + / -20% (e.g., + / -10%, etc.) of the longitudinal midpoint of the extraction opening or a geometric center distal to the longitudinal center. Applying suction may include drawing fluid through one or more buffer flow openings, which one or more buffer flow openings have a geometric center that is located at the longitudinal midpoint of the extraction opening or distal to the longitudinal midpoint. In any of these devices and methods, at least one buffer flow opening may be located distal to the longitudinal midpoint of the extraction opening so as to provide a rotational force as described herein.

[0048] Any of these methods may include cutting an elongated strip of clot material from the clot as the clot is driven against a proximal edge of the extraction opening and flipped relative to the extraction opening.

[0049] One or more buffer flow openings can be configured relative to the extraction opening such that fluid flow entering the aspiration catheter imparts a rotational force on the clot, driving the clot against the proximal edge of the extraction opening. The methods described herein may include automatically shutting off or reducing aspiration when clot material is no longer detected adjacent to the extraction opening or within the distal region.

[0050] Also described herein are extraction collection and reperfusion devices and methods of using them to extract clotted material from the vascular system in a manner that simplifies the safe return of aspirated blood to the patient and minimizes exposure of the blood to low negative pressure. These devices generally include an assembly that includes at least an upper chamber and a lower chamber. When connected to an extraction catheter, the upper chamber can receive and maintain a vacuum to allow extraction. Additionally, the upper chamber can contain a filter element that can filter the clotted material removed from the patient. In some embodiments, the upper chamber can be separated into two chambers connected via a tube fluid. In other embodiments, the filter element can be located in the lower chamber between the reperfusion valve and the reperfusion line. Blood can be transferred to the lower chamber in a manner that does not damage the blood or cause bubbling. Devices and methods of using them can allow blood to be returned immediately or almost immediately for reperfusion without the need for multiple transfers and without delaying the aspiration procedure.

[0051] For example, described herein is a device for perfusing collected blood and clots, the device comprising: an upper chamber, a lower chamber, a filter element located within the upper chamber and / or the lower chamber, wherein the filter element is configured to capture clots; a vacuum inlet that opens into the upper chamber and is configured to be coupled to a vacuum source; an extraction inlet that opens into the upper chamber, the extraction inlet being configured to be coupled to an extraction line through an extraction valve; a reperfusion outlet from the lower chamber, the reperfusion outlet being configured to be coupled to a reperfusion line (and flow from the reperfusion outlet to the reperfusion line can be controlled by a reperfusion valve); and a vacuum release valve in fluid communication with the upper chamber, wherein the reperfusion valve is configured to open when the vacuum release valve is open. In some examples, the reperfusion valve is configured to open only when the vacuum release valve is open.

[0052] Any of these devices may include a fine filter in fluid communication with the refill outlet.The coarse filter may be configured to be manually removed from the upper chamber by opening the top of the upper chamber.

[0053] Any of the devices for perfusing collected blood described herein may include an impermeable septum between an upper chamber and a lower chamber and one or more partition valves configured to form an opening through the impermeable septum. The partition valve may be configured to open automatically (e.g., when the pressure between the upper chamber and the lower chamber is normalized to approximately the same pressure and when the weight of the blood in the upper chamber exceeds the rupture pressure of the one or more valves). For example, the one or more partition valves may include one or more umbrella valves configured to open when the fluid pressure against the valve exceeds the rupture pressure. Alternatively, in some examples, the device may be configured such that the partition valve is actively controlled to open, for example, when the system detects that a sufficient amount of blood is in the upper chamber and when the pressure difference between the upper chamber and the lower chamber is approximately normalized (by directly detecting the pressure in the upper chamber and / or the lower chamber or by detecting that the vacuum release valve in the upper chamber is opened). In some examples, the device may include a processor configured to coordinate opening of the isolation valve and the vacuum release valve.

[0054] In any of these examples, the lower chamber can include a pressure regulator opening. In some examples, the pressure regulator opening is configured to vent to atmosphere. Alternatively or additionally, the lower chamber can be configured to maintain a pressure below atmospheric pressure, for example, so that the upper and lower chamber pressures can be quickly normalized, and the upper chamber can maintain some negative pressure (e.g., vacuum) even when blood is transferred from the upper chamber to the lower chamber.

[0055] Typically, the pressure within the lower chamber may be controlled to prevent or minimize bubbling, and may be configured such that the refill valve will not open until the pressure within the lower chamber is approximately at atmospheric pressure.

[0056] In any of these devices, the device can be configured so that blood, and in particular captured clot material, can be directly visualized. For example, the upper chamber and the lower chamber can be configured to allow direct visualization of blood passing through the walls of the upper chamber and the lower chamber. In some examples, the device can include a separate filtration (coarse filtration) chamber located upstream of the upper chamber, which chamber (e.g., in a planar configuration) is configured to allow direct visualization of the clot material as it is strained. The filtration chamber can be opened to allow removal of clot material from the coarse filter without destroying the device.

[0057] Any of these devices may include a refill fluid line in fluid communication with a refill outlet through a refill valve. Similarly, any of these devices may include a vacuum source coupled to a vacuum inlet.

[0058] In some examples, the device for perfusing the collected blood includes separate (separated) upper and lower chambers, each of which can be pressure controlled to allow transfer from the upper chamber to the lower chamber by gravity. The lower chamber can also be configured to allow easy reperfusion of the collected blood back into the patient directly or indirectly, including by collection in a syringe or other container for subsequent reperfusion.

[0059] For example, a device for perfusing collected blood may include: an upper chamber; a lower chamber; an impermeable partition between the upper chamber and the lower chamber; a partition valve configured to form an opening through the impermeable partition; a vacuum inlet that opens into the upper chamber and is configured to be connected to a vacuum source; an extraction inlet that opens into the upper chamber; a reperfusion outlet that exits the lower chamber; and a pressure regulating opening that opens into the lower chamber, the pressure regulating opening being configured to maintain the pressure in the lower chamber higher than the pressure in the upper chamber and higher than the bubble pressure of the blood, wherein the partition valve is configured to open to allow blood to flow from the upper chamber into the lower chamber.

[0060] Any of these devices can include a coarse filter in fluid communication with the upper chamber. The coarse filter is configured to have holes that are sized to limit the ability of clots to pass through, but can allow blood (including cells, such as red blood cells, etc.) to pass unimpeded. In some examples, the coarse filter can be a mesh, and / or can have holes that are large enough to allow liquid blood to pass easily but small enough to prevent the passage of clot material. In some examples, the coarse filter is removable to allow manual removal of blood clots.

[0061] As described above, in some examples, the device includes a clot collection and visualization chamber that includes a coarse filter and is in fluid communication with the upper chamber through an extraction inlet.

[0062] In some examples, the pressure regulating opening in the lower chamber can be one or more openings to the atmosphere. The opening can be direct or can be covered with a filter to prevent contamination. Alternatively, in some examples, the lower chamber can include a connection to a vacuum source (or a second vacuum source), and the lower chamber can be maintained at a pressure closer to atmospheric pressure than the upper chamber, while still maintaining above a pressure that will cause increased bubbling. In some examples, the pressure regulating opening includes a valve that controllably connects the lower chamber to a negative pressure source.

[0063] Any of these means may include, for example, one or more pressure sensors in the upper chamber and / or the lower chamber. Alternatively, in some examples, no additional sensors are included.

[0064] The apparatus may include a vacuum relief valve in fluid communication with the upper chamber and / or the lower chamber.As described above, the one or more partition valves may include one or more umbrella valves configured to open when fluid pressure on the valve exceeds a rupture pressure.

[0065] Typically, the upper chamber and the lower chamber can be configured to allow direct visualization of blood through the walls of the upper chamber and the lower chamber. The device can include a reperfusion fluid line in fluid communication with the reperfusion outlet through a reperfusion valve. The device can also include a fine filter in fluid communication with the reperfusion line. Any of these devices can include a vacuum source coupled to the vacuum inlet.

[0066] For example, a device for perfusing collected blood may include: an upper chamber; a lower chamber; an impermeable partition between the upper chamber and the lower chamber; one or more partition valves configured to form an opening through the impermeable partition; a coarse filter in fluid communication with the upper chamber; a vacuum inlet that opens into the upper chamber and is configured to be connected to a vacuum source; a vacuum release valve in the upper chamber; an extraction inlet that opens into the upper chamber; and a vacuum release valve between the extraction inlet and an extraction valve extending from the extraction inlet. an extraction valve between the lines; a reperfusion outlet located in the lower chamber and configured to be in fluid communication with the reperfusion fluid line through the reperfusion valve; a pressure regulating opening leading to the lower chamber, the pressure regulating opening being configured to maintain the pressure in the lower chamber higher than the pressure in the upper chamber and higher than the bubbling pressure of the blood; and a fine filter in fluid communication with the reperfusion line, wherein one or more isolation valves are configured to open when the vacuum release valve is opened to allow blood to flow from the upper chamber into the lower chamber.

[0067] The present invention also describes a method for reperfusing blood during a clot removal procedure, the method comprising: filling an upper chamber of a reperfusion system with a vacuum; opening an extraction valve and drawing blood from a patient into the upper chamber through an extraction inlet, and filtering clot material from the blood using a coarse filter in fluid communication with the upper chamber; collecting blood from the upper chamber in a lower chamber after filtering the clot material, wherein collecting blood from the upper chamber in the lower chamber comprises: opening a partition valve separating the upper chamber from the lower chamber when the vacuum in the upper chamber is released to approximately the pressure of the lower chamber, so that blood is discharged from the upper chamber into the lower chamber by gravity; opening a reperfusion valve in fluid communication with the lower chamber after the pressure in the lower chamber is approximately at atmospheric pressure; and returning blood from the lower chamber to the patient.

[0068] In any of these methods, opening the partition valve may include controlling the partition valve to open when the pressure in the upper chamber is substantially the same as the pressure in the lower chamber. In some examples, opening the partition valve may include automatically opening the partition valve when the pressure in the upper chamber is substantially the same as the pressure in the lower chamber and the weight of the fluid on the partition valve is greater than a rupture pressure of the partition valve. Collecting blood from the upper chamber in the lower chamber may include releasing pressure in the upper chamber by opening a vacuum release valve.

[0069] Any of these methods may include filtering the blood with a fine filter before returning the blood from the lower chamber to the patient. Any of these methods may include removing clotted material from the coarse filter. Any of these methods may include refilling the upper chamber with a vacuum to allow further extraction after the blood is collected in the lower chamber.

[0070] Filling the upper chamber of the reperfusion system with a vacuum may include operating a vacuum source coupled to the upper chamber through a vacuum inlet. In some examples, the method may include keeping the vacuum source continuously open while opening the extraction valve, collecting blood, and opening the reperfusion valve.

[0071] For example, a method for reperfusing blood during a clot removal procedure may include: filling an upper chamber of a reperfusion system with a vacuum; opening an extraction valve and drawing blood from a patient into the upper chamber through an extraction inlet leading to the upper chamber, and filtering clot material from the blood using a coarse filter in fluid communication with the upper chamber; normalizing the pressure between the upper chamber and the lower chamber; opening a partition valve separating the upper chamber from the lower chamber so that blood flows from the upper chamber into the lower chamber; refilling the upper chamber with a vacuum to allow further extraction; opening a reperfusion valve in fluid communication with the lower chamber; and returning blood from the lower chamber to the patient.

[0072] The lower chamber may be maintained at atmospheric pressure. The lower chamber may be maintained at a pressure between atmospheric pressure and blood bubble pressure (e.g., about 600 mmHg). Any of these methods may include removing clotted material from a coarse filter.

[0073] All methods and apparatus described herein are contemplated herein in any combination and may be used to achieve the benefits as described herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0075] A better understanding of the features and advantages of the methods and apparatus described herein will be obtained by referring to the following detailed description setting forth illustrative embodiments and the accompanying drawings, in which:

[0076] Figure 1 One example of an aspiration catheter as described herein is shown.

[0077] Figure 2A A suction catheter (such as Figure 2A A perspective view of an example of a distal region of a catheter shown.

[0078] Figure 2B Shows Figure 2A Opaque view of the distal region of the aspiration catheter.

[0079] Figure 3A is a top view of another example of a distal region of an aspiration catheter.

[0080] Figure 3B is a perspective view of the distal region of the aspiration catheter showing the flow lines entering the aspiration catheter when suction is applied.

[0081] Figure 3C yes Figure 3B A side cross-sectional view of the aspiration catheter is shown.

[0082] Figure 4A An aspiration catheter without a buffer flow opening is shown, showing blockage of clotted material ("lollipop formation") at the extraction opening on the side of the aspiration catheter.

[0083] Figure 4B-4C The effect of the buffer flow opening on clot extraction is shown, showing the application of a rotational force on the clot material such that the clot material is driven against the proximal opening edge of the extraction opening, forming a strip of clot that is moved into the aspiration lumen for removal from the body.

[0084] Figure 5A-5G An example of removing a clot model using an aspiration catheter including a buffer flow opening as described herein is shown. Based on the configuration of the buffer flow opening, a rotational force is applied to the clot through the extraction chamber, causing the clot to be driven against the proximal edge region of the extraction opening, including rotating (and flipping) the clot to allow a strip of clot model material to be cut off.

[0085] Figure 6A-6E An example of a distal region of an aspiration catheter device is shown. Fig. 6A An example of a distal region including a single buffer flow opening is shown. Figure 6B An example is shown having two buffer flow openings positioned distal to the transverse midline of the extraction opening. Figure 6C An example is shown having two buffer flow openings positioned at approximately the transverse midline of the extraction opening. Fig.6D An example is shown with an open distal end that serves as the only buffer flow opening. Fig. 6E An example of a distal region is shown that includes four buffer flow openings on either side of an inner guide channel in which a diagnostic guide catheter may be positioned.

[0086] Figure 7A-7E Examples of distal regions of aspiration catheters as described herein are shown, including buffer flow openings of varying sizes, numbers, and locations.

[0087] Figure 8A-8C An example of a distal region of an aspiration catheter including a flow opening that is not properly configured to function as a buffer flow opening is shown. Fig. 8A (a single opening, located proximal to the longitudinal center of the extraction opening) and Figure 8B (The opening on the same side as the extraction opening is located proximal to the extraction opening) In both figures, the generated flow fails to exert a rotational force on the clotted material. Figure 8C In the embodiment shown, two openings located approximately at the longitudinal center of the extraction opening and radially offset by about 90 degrees from the transverse centerline of the extraction opening failed approximately 50% of the time.

[0088] Figure 9A-9E An example of a distal region including an opening being tested to determine the proper longitudinal position of the opening is shown, and the time required to extract tissue is shown.

[0089] Figure 10A-10C Examples of different distal regions including buffer flow openings with different sized openings (surface areas) are shown.

[0090] Fig.11 is a table showing different relative size openings of the buffer flow openings compared to the size of the extraction opening (eg, ratio of total area of ​​the buffer flow opening to the extraction).

[0091] Fig.12 is a table showing the test results of different relative size openings of the buffer flow opening compared to the size of the extraction opening from Table 11 on the extraction flow rate of captured clot material.

[0092] Fig.13 yes Fig.12 A graph of the data is shown.

[0093] Figures 14A-14D Examples of different distal regions of an aspiration catheter having different numbers of buffer flow openings (all normalized to the same total opening area) are shown.

[0094] Fig.15 It is shown that the use Figure 14A-14B A graph showing the effect of different numbers of buffer flow openings on the time to extract a clot model in the distal region shown.

[0095] Fig.16 An example distal region of an aspiration catheter is shown including a buffer flow opening and a shield region to offset the buffer flow opening from a wall of a lumen and / or clotted material within the lumen during use.

[0096] Fig.17 An example of an aspiration catheter is schematically shown, the aspiration catheter comprising a displacement protrusion extending from an outer surface of a distal region, the displacement protrusion being configured to displace an outer opening of a buffer flow opening from a wall of a vessel. Fig.17A is to show that using Fig.17 A graph of catheter pressure versus time is shown.

[0097] Fig.18 An example of an aspiration catheter including a mechanical repositioner is schematically shown.

[0098] Figures 19A-19D An example of an aspiration catheter including a buffer flow opening that operates on clot material as described herein is shown.

[0099] Fig. 20A An example of a clot strip collected using an aspiration catheter with a buffer flow opening as described herein is shown.

[0100] Fig. 20B Schematically shows a method similar to that used to collect Fig. 20A The distal region of the aspiration catheter of the clot strip aspiration catheter shown in FIG.

[0101] Fig.21A and Fig. 21B Schematically illustrated is a tip including a buffer valve opening configured to have an outlet opposite to a longitudinal midline of the extraction opening (and at least one outlet distal to the longitudinal midline of the extraction opening) and to apply a buffer flow from a proximal fluid source (e.g., an external fluid source).

[0102] Fig. 21C The schematic diagram shows the use of Fig.21A and Fig. 21B An example of a device with a buffered flow opening configuration is shown.

[0103] Fig.21D and Fig.21E Shown are top and bottom views, respectively, of one example of a buffered flow device as described herein.

[0104] Fig.21F Shows such as Figure 21D-Figure 21E An example of a proximal (e.g., handle) region of a device of a buffered flow aspiration catheter device.

[0105] Figure 21G Shown through Fig.21F (pass Fig.21F Cross-section of the proximal portion of the suction catheter (taken along line AA in FIG. ).

[0106] Fig.21H is similar to Figure 21D-21GA side view of an example of a distal region of an aspiration catheter in contact with clot material is shown in FIG.

[0107] Fig.21I Schematically shows Fig.21H Operation of the handle area of ​​the suction catheter.

[0108] Fig. 22 A method of removing clotted material using an aspiration catheter device including a buffer flow opening as described herein is schematically illustrated.

[0109] Fig.23A A cross section transverse to the long axis through the distal region of an example aspiration catheter is shown, illustrating the region of buffer flow beneath the aspiration opening.

[0110] Fig. 23B A side view of a distal region of an example of an aspiration catheter including a buffer flow opening that maintains a region of buffer flow below the extraction opening is shown.

[0111] Fig.24A A side view of a distal region of an example of an aspiration catheter including a buffer flow opening is shown, illustrating the offset of the aspiration opening relative to the centerline of the lumen of the catheter shaft.

[0112] Figure 24B1 and Figure 24B2 Shown are side-facing and end-facing views of an aspiration catheter as described herein.

[0113] Fig.24C1 and Fig.24C2 Shown are side-facing and end-facing views of an aspiration catheter as described herein.

[0114] Fig.24D1 and Fig.24D2 Shown are side-facing and end-facing views of an aspiration catheter as described herein.

[0115] Fig.25 An example distal region of an aspiration catheter including a buffer flow opening is shown, wherein the distal tip region includes a vortex region (tip retention region) in the region of the aspiration lumen distal to the aspiration opening.

[0116] Fig.26 A cross-section through the distal region of an example aspiration catheter transverse to the long axis is shown, the distal region including a region within a buffer flow region that is shielded by an internal (e.g., navigation) lumen within the aspiration lumen to prevent clogging by clot material.

[0117] Figure 27A-27BAn example of an aspiration catheter as described herein is shown that is configured to apply external saline in addition to (or in some examples, instead of) applying a buffer flow through one or more buffer flow openings (e.g., from a proximal end of the device).

[0118] Fig.28A and Fig.28B An example of an aspiration catheter as described herein is shown that is configured to apply external saline in addition to (or in some examples, instead of) applying a buffer flow from a distal end of an auxiliary lumen (e.g., a navigation lumen) through one or more buffer flow openings. Fig.28A yes Fig.28B Schematic diagram of the catheter shown in , with a portion of the distal end cut away to show internal details.

[0119] Fig.29 A schematic diagram of an example of a distal end of an aspiration catheter configured to apply external saline in addition to (or in some examples, instead of) applying a buffer flow through one or more buffer flow openings is shown. Fig.29 A portion of the distal region of the midcatheter is shown cut away to reveal internal detail.

[0120] Fig.30 Another example of a distal end of an aspiration catheter configured to apply external saline in addition to (or in some examples, instead of) applying a buffer flow through one or more buffer flow openings is schematically shown. Fig.30 A portion of the distal region of the midcatheter is shown cut away to reveal internal detail.

[0121] Fig.31 Another example of an aspiration catheter configured to apply an external fluid (in this example) is shown. The fluid can be blood that enters the extraction tip of the extraction catheter from an area distal to the clot of the vessel using an extendable lumen.

[0122] Fig.32 One example of a device for collecting and / or perfusing blood, such as during a clot capture procedure, is schematically illustrated.

[0123] Figure 33A-Figure 33E An example of a method of operating a device for collecting and / or reperfusing blood into a patient is shown, e.g. Fig.32 The device shown in .

[0124] Fig.34 One example of a device for collecting and / or perfusing blood, for example during a clot capture procedure, including a partition valve is schematically illustrated.

[0125] Figures 35A-35BThe operation of one example of a partition valve (shown as an umbrella valve in this example) is shown.

[0126] Figure 36A-Figure 36E The operation of a device (e.g., Fig.34 An example of a method of the device shown in ).

[0127] Fig.37 Examples of devices for collecting and / or perfusing blood, such as during a clot capture procedure, are schematically illustrated.

[0128] Fig.38 An example of a method of reperfusing blood during a clot removal procedure is schematically illustrated.

[0129] Detailed Description

[0130] The extraction methods and apparatus described herein may include an extraction catheter and a reperfusion device. These devices may be used together (eg, as part of the same system) or separately.

[0131] Typically, the extraction catheters described herein (also equivalently referred to as suction catheters) are configured to remove clot material from a patient. These extraction catheters can be configured to remove clots in longer strips, which can prevent or reduce the risk of releasing smaller clot fragments back into the vasculature. Longer strips can also allow postoperative analysis, including more accurately determining the amount of clots removed and the characteristics of clots. The extraction catheters described herein can also be configured to prevent the catheter from being blocked by clots, which can occur when the size of the clot material is larger than the extraction opening into the extraction catheter, which is usually the case. This type of clot is generally referred to as "forming a lollipop-shaped piece". The extraction catheters described herein can use one or more buffer flow openings to impart a rotational force on the clot at the extraction opening; in some cases, this can cause the clot material to rotate or flip relative to the extraction opening, thereby driving the clot material against the proximal edge of the extraction opening. The buffer flow opening can also generate an entrained flow of fluid (e.g., blood) in the suction chamber of the catheter, thereby attracting the cut strip of clot material into the suction chamber. Additionally, these extraction catheters may be configured to remove clots more quickly and may remove less blood from the patient.

[0132] Typically, the apparatus described herein (e.g., devices and systems including extraction catheters) may include a laterally positioned extraction opening that may be on the tapered side of the distal region of the catheter. The tapered shape may help the device navigate the cavity of the vessel. The distal region (sometimes referred to herein as the distal end region or simply referred to as the distal end) may be formed by a generally soft material. In some examples, the catheter may include one or more cavities. At least one cavity may be configured as a suction portion (or extraction cavity) communicated with the extraction opening. In some examples, the extraction catheter may also include a second cavity, which may be referred to as a guide cavity or a diagnostic catheter cavity, which may extend distally through the extraction opening. The guide cavity may be configured to allow a guide wire, a guide catheter, a diagnostic catheter, etc. to pass through. The guide cavity may lead to the extraction cavity. In some examples, the guide cavity at least partially leads to the extraction cavity, so that when other elongated members (e.g., guide wires, guide catheters, diagnostic catheters, etc.) are not present in the guide cavity, fluid may pass through the distal opening from the outside of the catheter and enter the extraction cavity.

[0133] Any of the devices described herein may include one or more buffer flow openings that are configured to prevent blockage and drive the clot material against the proximal edge of the extraction opening. In some examples, the buffer flow opening can be configured to generate a rotational force on the clot material at the extraction opening, which can help prevent blockage and / or cut off a strip of clot material so that the clot material strip can be entrained into the cavity. As described in detail herein. The buffer flow opening can be configured in this manner based on one or more of the following: the longitudinal position relative to the extraction opening, the radial position relative to the extraction opening, the number of openings, and / or the total size of the opening relative to the size of the extraction opening.

[0134] A common problem with many venous thrombectomy catheters that use extraction to remove blood clots from the pulmonary artery is that the clot blocks the distal end of the catheter, resulting in a lollipop effect. The catheter then needs to be removed from the patient and unblocked during surgery before the device can remove the remaining clot in the patient's body. This often happens when the blood clot is larger than the extraction lumen of the catheter (the blood clot is removed through the extraction lumen of the catheter). If the catheter is not sharp enough to core the blood clot, the blood clot is wedged into the distal end of the catheter. Once the distal extraction opening of the catheter is blocked, the flow rate tends to zero, and the dynamic interaction (coring) between the clot and the end of the clot stops. Although in some cases, the catheter (e.g., extraction opening) can be made sharp enough to allow coring of the clot; however, this sharpness can cause other problems and may cause vascular trauma or perforation. The extraction catheter described herein, which includes one or more buffer flow openings, can provide effective clot extraction and / or shearing while ensuring that the end and the clot orifice are non-traumatic. The extraction catheters described herein may include a distal region of the catheter that, in combination with the configuration of one or more buffer flow openings, can bias clot material to a proximal edge region of the extraction opening where shearing can occur without obstructing flow through the catheter.

[0135] The distal tip region can also be configured to act as an integrated dilator and atraumatic tip, allowing the user to advance the extraction catheter from the right femoral vein through the heart and into the pulmonary artery. It can also allow the user to move the catheter and extract at the same time if necessary.

[0136] Figure 1 One example of an extraction ("suction") catheter as described herein is shown. In any of the devices described herein, the distal end region 118 of the extraction catheter 100 is configured to be atraumatic and can taper from a distal to proximal direction, which can facilitate insertion and advancement through a vessel and through the heart. The distal region 118 extends from the distal end of the elongated catheter body 110. The distal region 118 of the extraction (suction) catheter can have an extraction opening 104 on the side. The extraction catheter can also include a distal opening 105 into a guide lumen. In some examples, the lumen and distal opening can be sufficient to allow a 4Fr catheter to be advanced and rotated through the lumen, and the 4Fr catheter can be placed over a guide wire during surgery. Figure 1 In the illustrated example, a diagnostic catheter 106 is shown extending distally from a guide lumen and protruding from a distal opening 105 ; a guide wire 111 protrudes from the lumen of the diagnostic catheter 106 .

[0137] The distal region (e.g., "tip") 118 can be made of an elastomer (e.g., 55D TPU) that is soft enough to pass through the heart without causing vascular damage, while being stiff enough to resist collapse under a full vacuum. In some examples, the distal region can be made of a more flexible material, and reinforcement members can be used to increase the hoop strength in the area of ​​the extraction opening 104. This is particularly useful in Figure 2A , which shows an example of a distal region 218 including a hoop strength support 212. The hoop strength support 212 may be a stainless steel reinforcement member, such as a partial ring or a harder plastic overmolded portion.

[0138] exist Figure 2A and Figure 2B In the embodiment of the present invention, the tip 218 has an extraction opening 204 on its inclined (conical) face through which clots can be extracted. The opening is elongated along the long axis (longitudinal axis) of the catheter and is wider at the proximal end than at the distal end. The entire edge of the extraction opening 204 or only the proximal edge 208 of the opening can be configured to have additional raised material around it to help resist collapse under vacuum. The raised area can be configured as a lip 220 (which can be referred to as a reinforced lip, which is reinforced by including additional material, and / or can be reinforced by including stronger and / or harder materials). These design elements can allow the extraction opening to create a shear quadrant (proximal edge 208) through which clots can be sheared when the vacuum is turned on. The proximal edge area at Figure 2B , and is likely where most of the clot shearing occurs. As will be described in more detail, one or more buffer flow openings and the tip shape can result in flow dynamics at the tip that drive clot material against this proximal edge region during extraction.

[0139] exist Figure 2A and Figure 2B In the embodiment of the present invention, the distal region 218 may also include the distal opening 205 as described above. The distal region 218 may also include one or more buffer flow openings 214.

[0140] The extraction opening can generally be shaped to produce a relatively high velocity flow through the proximal edge of the tip. During extraction, a tip opening that is wider at the more proximal edge ("proximal quadrant") and substantially wider than the distal quadrant can allow a higher flow velocity to occur through this proximal edge region of the opening. For example, Figure 3A A top view of an example of a tip as described herein looking down on an extraction opening 304 is shown. In this example, the tip region includes a distal opening 316 leading to an extraction cavity and a guide cavity. An array of buffer flow openings 307 is located radially opposite the extraction opening 304. A proximal edge 308 (or proximal quadrant) is indicated.

[0141] The shape of the extraction opening combined with the location, shape and size of the buffer flow opening can increase the force on the clot at the proximal edge of the extraction opening, such as Figure 3B as shown by the streamlines shown. The buffer flow opening can be positioned to help maintain a high flow rate in the device as the clot approaches the extraction opening, and can keep the clot biased toward the sheared proximal edge of the extraction opening. In this example, a small buffer flow opening is positioned on the opposite side of the end relative to the orifice (e.g., radially offset from the longitudinal midline of the extraction opening) so that when the flow rate through the extraction opening begins to decrease as the clot begins to block the extraction opening, the buffer flow opening can increase the flow rate to impart a rotational force on the clot, rotate and / or flip the clot relative to the extraction opening, and help ensure that the clot material remains moving and is cut against the proximal edge. This can prevent flow through the catheter from stopping and can prevent the catheter from clogging, even when removing long strips of clot. The buffer flow opening creates a "fluid cushion" to ensure that the catheter does not clog and that there is continuous flow through the catheter and into the catheter. This also Figure 3C , clot material 355 is shown being driven against the proximal edge 308 of the extraction opening 307. Flow 380 from the buffer flow opening 307 can combine with the flow from the extraction opening 304 to impart a rotational force on the clot material 355.

[0142] For example, during extraction, when there is no clot near the extraction opening, most of the flow can be generated through the orifice, and the buffer flow opening can provide relatively little flow into the extraction catheter. As clotted material approaches the distal region of the catheter and is attracted to the extraction opening, flow through the buffer flow opening can begin to increase, thereby creating a fluid buffer that will drive the clot against the proximal edge of the extraction opening at the end and maintain flow in the extraction catheter, such that continuous flow moves in the lumen of the catheter to transport the clot proximally toward the collection chamber.

[0143] The buffer flow openings can be configured to be positioned slightly distal to the proximal edge of the extraction opening (and in some examples, at least one opening can be distal to the longitudinal midline of the extraction opening), and can be in multiple locations, with different shapes or positions. Examples of locations and sizes of effective buffer flow openings are as follows. The buffer flow openings can generally form a "flow pillow" that distributes the flow over a larger area. Thus, the buffer flow openings can have an optimal size, number, and location to maintain flow through the extraction opening without negatively affecting clot engagement.

[0144] For example, Figure 4A An example of a catheter 401 is shown having an extraction opening on the side of the distal region that does not include any buffer flow openings. Figure 4A , clotted material 434 has become blocked (“lollipopped”) onto extraction opening 404 .

[0145] Figure 4B and Figure 4C An example of an extraction catheter 400 including a plurality of buffer flow openings as described herein is shown. As the clot approaches the end, these buffer flow openings allow for continued flow, imparting a rotational force 436 on the clot 434, and creating a flow buffer to ensure that the clot does not form a lollipop on the end of the extraction catheter 400. As shown, the clot material is driven by the suction flow from both the extraction openings and the buffer flow openings, causing the clot material 434 to rotate against the proximal edge of the extraction opening to shear and cut a strip of clot material, which is then entrained by the flow into the extraction lumen without clogging.

[0146] Figure 5A-5G Another example of a model clot material 534 is shown, which, when suction is applied through an extraction lumen of an aspiration catheter 500 having multiple buffer flow openings, is rotated and flipped as it is driven against the proximal edge of the extraction openings. Figure 5A-5G The movement of the clotted material is shown as it rotates against the proximal edge of the extraction opening. Figure 5A When the extraction opening is close enough to the clot material, the clot material is attracted to the extraction opening. The flow of fluid (e.g., blood) from the buffer flow opening into the catheter 500 causes the clot material to be pulled proximally against the proximal edge of the extraction opening, causing the clot material to move proximally relative to the distal end region, such as Figure 5B Flow from the extraction chamber and the buffer flow opening causes the clot material 534 to flip relative to the extraction opening, as shown in FIG. Figure 5C and Figure 5D As the clotted material rotates (e.g., flips) relative to the extraction opening, it continues to be driven against the proximal edge of the extraction opening, causing the strip (or strips) of material to be cut off and pulled into the suction lumen of the catheter 500, as shown. Figure 5E-5G as shown, until all clotted material is removed.

[0147] As described above, configuration of one or more parameters of the openings may allow the openings to be Figure 4B-4C and Figure 5A-5G, so that they act as buffer flow openings. These parameters can be optimized so that the buffer flow opening applies an appropriate rotational force to the clot material adjacent to the extraction opening and so that the removal of the clot material is fast enough (e.g., so that the time to extract the clot is below a target level, which can minimize blood loss and surgical time). These parameters of the buffer flow openings can include the longitudinal (e.g., axial) position of one or more buffer flow openings relative to the extraction opening, the radial position of the buffer flow opening relative to the extraction opening, the relative relationship of the total size of all openings of the buffer flow opening relative to the size of the extraction opening, and the number of openings. For example, one or more buffer flow openings can generally be positioned so that they are distal to the distal edge region of the extraction opening, and more specifically, at least one of the buffer flow openings should be distal to the longitudinal midline of the extraction opening and / or so that the average longitudinal position of the buffer flow openings is at the midline of the extraction opening or distal to the midline. In addition, the buffer flow opening can be positioned radially (relative to the extraction opening) such that the buffer flow opening is radially offset from the longitudinal centerline of the extraction opening by more than 90 degrees (e.g., greater than 100 degrees, greater than 110 degrees, greater than 120 degrees, between 90-180 degrees, between 100-180 degrees, etc.). The angle of the buffer flow opening relative to the centerline of the extraction opening can be measured from the middle of the buffer flow opening.

[0148] Typically, the relative relationship between the size of the extraction opening and the sum of the sizes of the buffer flow openings can be between about 10:1 and 18:1 (e.g., between about 11:10 and 17:1, between about 10:1 and 16:1, between about 12:1 and 16:1, between about 12:1 and 14:1, etc.). Typically, too large a buffer flow opening does not work. Typically, the applied vacuum can be greater than about 510 mmHg (e.g., the difference between the pressure in the vessel and the pressure in the extraction chamber can be greater than 250 mmHg).

[0149] Figure 6A-6E An example of a distal region (tip) including a buffer flow opening is shown. Fig. 6A A first example of a tip having a single buffer flow opening 614 is shown, which is positioned distal to the centerline 644 of the extraction opening 604. Fig. 6A In the embodiment, the buffer flow opening is blocked by the diagnostic catheter 606 extending through the guide cavity. Therefore, the buffer flow opening can be opened or closed by inserting or removing the diagnostic catheter. When the diagnostic catheter does not cover the buffer flow opening, the buffer flow opening can pass through the guide cavity to allow fluid from outside the end to enter the extraction cavity. In some examples, such as Figure 6B and Figure 6C As shown, the buffer flow opening is radially offset from the guide passage (and any diagnostic catheter that may be present). Figure 6BIn FIG. 6 , two buffer flow openings 614 , 614 ′ are positioned distally of the centerline 644 of the extraction opening 604 . Figure 6C , two buffer flow openings 614 , 614 ′ are positioned distally of a centerline 644 of the extraction opening 604 .

[0150] In any of the aspiration catheters described herein, the buffer flow opening may be the distal opening 616, such as Fig.6D In this example, the only buffer flow opening is the distal opening; in some examples, a lateral buffer flow opening opposite to the extraction opening may also be included.

[0151] Fig. 6E A perspective view of an example of an end having four buffer flow openings is shown, all positioned at or distal to the midline of the extraction opening and all radially offset approximately 160 degrees from the longitudinal midline of the extraction opening so that they are not blocked by the presence of a diagnostic catheter 606, as shown.

[0152] Figure 6A-6E The buffer flow openings in are all circular openings. In some examples, the buffer flow openings can be other shapes, including elliptical, rectangular, triangular, etc. In addition, the buffer flow openings described herein are mainly formed directly by the wall of the end (and / or any guide cavity). In some examples, the buffer flow openings can have an output leading to the extraction cavity at the position indicated above (e.g., usually at the distal end of the proximal opening and in particular, at the longitudinal midline of the extraction opening or at the distal end of the longitudinal midline), and the input entering the buffer flow opening can be located more proximally, including extending (e.g., by a buffer flow channel) to the proximal end of the device or extending to the more proximal region of the catheter. The buffer flow channel can be preferred, wherein, for example, the flow from the buffer flow opening is applied forward, rather than being applied only by the applied extraction from the extraction cavity.

[0153] Figure 7A-7E Examples of buffer flow openings having different locations, orientations, numbers, and shapes are shown. In general, the parameters of the buffer flow openings may be selected so as to minimize blood loss and minimize the time required to remove a clot from a vessel. Fig. 7A An example of a tip having two buffer flow openings 714 located approximately at the midline of the extraction opening is shown (similar to Figure 6C ), where each opening has a diameter of approximately 1 mm. Figure 7B An example is shown in which the buffer flow opening 714 is an elongated slot having dimensions of 0.7 mm x 8 mm. Figure 7C An example of an array of 9 buffer flow openings (3 x 3) 714 positioned distal to the midline of the extraction opening is shown. Each buffer flow opening has a diameter of 0.7 mm. Fig.7DAn example of the end of an array with 20 buffer flow openings (4×5) 714 is shown, each having a diameter of approximately 0.5 mm. Fig. 7E Shows something like Figure 6B An example of a distal end having two buffer flow openings 714 positioned distal to the midline of the extraction opening, each buffer flow opening having a diameter of about 1 mm. Figure 7A-7E to determine the characteristics of the buffer flow opening that best removes clotted material with minimal blood loss.

[0154] Figure 8A-8C An example of a tip having an opening 817 is shown that does not operate as a buffer flow opening to generate rotational forces and buffer flow as described herein. Fig. 8A , the tip includes a very large opening 817 and cannot induce rotational forces or buffer flow. Figure 8B A tip having two smaller openings 817 located proximal to the extraction opening is shown (at Figure 8B In the embodiment, the opening is also positioned at the same radial position as the extraction opening, and similar results are observed when the opening is positioned radially offset from the extraction opening), which also fails to generate rotational force and buffer flow. Figure 8A-B Neither of the ends can quickly remove the clot and prevent the formation of a lollipop-like piece. Figure 8C The tip shown results in a moderate success rate, clogging (eg, forming a lollipop) approximately 50% of the time. In this example, opening 817 is positioned at the midline (eg, longitudinal midline) of the extraction opening and is radially offset 90 degrees from the long axis (longitudinal axis) of the extraction opening.

[0155] Typically, the buffer flow opening should be located distal to the extraction opening. Figure 9A-9E As shown, when the buffer flow opening is positioned at the midline (e.g., center 944) of the extraction opening and / or distal to the midline (e.g., center 944), the effectiveness of the buffer flow opening in preventing clogging and removing the clot material strip is significantly increased. Figure 9A-9E The distal end shown was used to estimate the time required to remove the clotted material (extraction time), as shown. In this example, for the distal end shown, the results showed that generally the closer the buffer flow opening was to the center of the opening 944, the faster the clotted material was removed. In addition, the more distal examples were able to generate greater rotational forces on the clotted material, thereby preventing blockages and allowing the removal of longer strips of clotted material.

[0156] Figure 10A-10C Tips with different relative opening sizes for the buffer flow opening (relative to the extraction opening) are shown. Fig. 10A The opening is a single hole with a diameter of 4 mm (similar to Fig. 8AThe hole shown in FIG. 1 is about 12.57 mm 2 .exist Figure 10A-10C In each of the extraction openings, the extraction opening has a width of about 35.63 mm. 2 area. Fig. 10A The ratio of extraction openings to additional openings (e.g., buffer flow openings) in is about 2.83:1 (thus, the additional openings are about 35.3% of the extraction opening area). Fig. 10B In the present invention, an array of 9 openings was tested, each with a diameter of 0.5 mm, with a gap of about 1.76 mm for additional openings (e.g., buffer flow openings). 2 The total open area of Fig. 10B The ratio of extraction openings to additional openings (e.g., buffer flow openings) in is about 20:1, and the additional opening area is about 4.9% of the extraction opening area. Fig. 10C In the test, two openings were tested, each with a diameter of 1 mm, with about 1.57 mm for additional openings (e.g., buffer flow openings). 2 Therefore, Fig. 10C The ratio of extraction openings to additional openings (eg, buffer flow openings) in is approximately 23:1, and the additional opening area is approximately 4.4% of the extraction opening area. Fig. 10A The end shown does not work, and Fig. 10B and Fig. 10C The opening at the end shown does serve as a buffer flow opening.

[0157] The effect of the size of the buffer flow opening on the ability of the tip to provide rotational force, prevent clogging, and quickly remove a strip of clotted material was examined for various buffer flow opening sizes. Fig.11 The table of shows examples of tips having a ratio of the opening area of ​​the buffer flow relative to the opening area of ​​the extraction opening. Fig.11 In the Figure 1, the ratio of the extraction opening size to the buffer flow opening size between 8 and 22 is listed, and the corresponding hole diameter and area are shown. These tips were tested in multiple experiments and the time to remove clots (no clogging) was measured, as shown in Figure 1. Fig.12 and Fig.13 shown. Fig.13 Graphically shows Fig.12 The results are shown in the table of . In these tests, a model clot material (e.g., 10cc of Flarp) was used in a vessel with a diameter of 22mm. A vacuum of 740mmHg was applied, and clot capture was recorded by video and analyzed frame by frame.

[0158] When only the time to extract the entire clot is considered, the ratio of the extraction opening area to the buffer flow opening area (total) exhibits an optimal range of between about 10:1 and 18:1 (e.g., between about 11:1 and 17:1, between about 10:1 and 16:1, between about 12:1 and 15:1, between about 12:1 and 14:1, etc.).

[0159] Similar experiments were performed to determine the optimal number of holes to use. In this set of experiments, the ratio of the extraction opening area to the buffer flow opening area was maintained at 12:1, with the number of holes varied between 2 and 8, and the holes were symmetrically distributed around the center line 1444 of the extraction opening, as shown in FIG. Figures 14A-14D The results are shown in the form of graphs. Fig.15 , it is shown that the time to aspirate an equivalent clot is approximately the same for between 2-4 buffer flow openings. After four, the value increases slightly with each additional pair of holes added. The number of holes can be greater than 8. In some examples, 1 to 26 holes can be used (e.g., 1 to 20 holes, 2 to 20 holes, etc.).

[0160] Any of the devices described herein can be configured to prevent clot material and / or vascular wall material from blocking the buffer flow opening. For example, any of these devices may include an extension (e.g., a shield) extending from the outer surface of the elongated body to prevent the buffer flow opening from becoming blocked. In some cases, the extension is a protrusion extending relative to the extraction opening, which is slightly distal to the buffer flow opening to prevent clot material from entering the buffer flow opening and / or prevent the cavity wall from covering (and blocking) the buffer flow opening.

[0161] For example, Fig.16 An example of a protrusion or shield 1662 is shown forming a distally facing wall around the buffer flow opening 1614. In this example, the protrusion is a T-shaped protrusion extending beyond the outer surface of the tip, which can allow space to be maintained with the vessel (lumen) wall and can prevent clot material from extending and covering the opening.

[0162] In some examples, the buffer flow opening may include a distal opening (eg, a distal tip opening from which a diagnostic catheter may exit). Other examples may include using a membrane / mesh / filter material over the buffer flow opening.

[0163] Thus, in any of these examples, the one or more raised protrusions within the tip may also create an area beneath the clot through which fluid may pass to keep the clot moving. In some examples, the raised protrusions may be the outer surface of a guide lumen (e.g., a tube through which a navigation catheter / diagnostic catheter passes). Alternatively, as Fig.16 As shown, the protrusion may be formed from one or more features built into the tip itself.

[0164] Thus, clogging of the aperture (buffer flow opening) can be prevented by including a raised barrier on the exterior of the tip that can create a mechanical stop to keep clots away from clogging the aperture. These clot barriers can be passive (e.g., rigid) or active (e.g., expandable, such as a balloon or spring-based member that can be controllably expanded and / or retracted from the proximal end of the device).

[0165] Instead of or in addition to the buffered flow openings described herein, any of these aspiration conduits may include a mechanical method for generating a continuous flow. For example, Fig.17 An example of a catheter 1700 is shown that includes an additional pressure source (e.g., bellows 1717) at the proximal end of the catheter that can rapidly increase and decrease the vacuum level in the shaft to create turbulence, thereby ensuring that the catheter is not blocked by a clot 1734 that is blocked to the end of the catheter, for example, by applying a force (F) to pump the bellows and change the pressure within the extraction lumen (e.g., by inserting ... Fig.17A shown).

[0166] Alternatively or additionally, Fig.18 Another example of a catheter 1800 having a mechanical connection system is shown having a distal member (e.g., a mechanical repositioner 1881) that can mechanically (rather than merely by flow) reposition the clot 1834 to prevent blockage of the extraction opening and ensure continuous flow.

[0167] In practice, the devices described herein including the buffer flow openings configured as described above can be used to remove blood clots in vivo. For example, Figures 19A-19D An example of an aspiration catheter is shown that includes a distal tip having multiple (e.g., 4) buffer flow openings positioned at or distal to the midline of the extraction opening, as shown above. The clotted material is positioned within the vessel, obstructing the vessel. Fig.19A As shown, the distal end of the aspiration catheter is initially shown positioned adjacent to the clotted material. Activating the aspiration causes the clotted material to be drawn into the aspiration opening of the aspiration catheter, proximally pulling the clot against the proximal edge of the aspiration opening, and cutting off a strip of material, as shown. Fig.19B The buffer flow opening delivers a flow that imparts a rotational force on the clot material, causing the clot material to flip (in Fig.19C ) and continues to be driven against the proximal edge of the extraction opening ( Fig.19D) until the clot material is removed. In smaller diameter vessels, where there is no room for the clot to flip or roll along the distal-to-proximal axis, the combination of the rotational force from the flow through the buffer flow opening and the extraction from the extraction opening moves the clot in a manner similar to the carriage of a typewriter; initially pulled proximally and driven against the proximal edge of the extraction opening (to cut), and then returned in the distal direction and pulled proximally again to allow further cutting. In this example, the clot was approximately 10 g (75 cc) and the side branch flow was approximately 25 cc / sec.

[0168] Typically, the aspiration catheters described herein have a tip (distal region) similar to that described above, e.g. Fig. 20B , which includes a tapered side with an extraction opening 2104 into the extraction chamber and located between 2-4 buffer flow openings 2114, clot material is removed in a long strip by driving the clot material against the proximal edge 2108. Fig. 20A shows the use of something like Fig. 20B An example of a strip of clotted material being removed at the end is shown. The clotted material 2034 is not significantly broken up, but is removed in long strips.

[0169] Any of the devices and methods described herein may include a buffer flow opening wherein an outlet of the buffer flow opening is separated from an inlet of the buffer flow opening by a longitudinal distance, rather than an opening as shown above wherein both the inlet of the opening and the outlet of the opening are within an end region of the device (and in some examples, the inlet may be directly opposite the outlet of the buffer flow opening).

[0170] For example, Figure 21A-21B A tip for a device as described herein is shown, wherein the buffer flow opening has an outlet positioned as described herein, wherein the buffer flow opening (outlet) is opposite the extraction opening such that at least one of the buffer flow opening outlets 2184 extends distally beyond the centerline of the extraction opening. The inlet can lead to a lumen 2188, which can be connected to a fluid source, such as Fig. 21C to provide a buffered stream. Fig. 21C In the embodiment of the present invention, an external buffer flow fluid 2189 is provided to the buffer flow opening outlet through the inlet. The device can be the same as the device described herein in other aspects. The flow through the buffer flow outlet can be coordinated with the application of extraction (for example, they can be turned on at the same time, or the buffer flow can be applied after the extraction starts).

[0171] Figure 21D-Figure 21IAnother aspiration catheter as described herein is shown that provides an external fluid to an area near a buffer flow opening on an aspiration tip so that the fluid can be drawn into the buffer flow opening and withdrawn back through the extraction lumen of the extraction catheter, thereby causing the clot to be lifted upward toward the proximal edge of the extraction opening as the clot passes through the opening. The infusion of the external fluid can be used in areas of the body with limited fluid within the vessel (e.g., peripheral veins) where the clot inflow has been reduced due to the proximal end. Fig.21D and Fig.21E Top and bottom views of the distal end of a catheter having an extraction opening 2104 positioned on a tapered side of the distal end of the aspiration catheter are shown. Four buffer flow openings 2114 are positioned about the longitudinal midline of the extraction opening 2104 on a side of the catheter opposite the extraction opening. A navigation lumen 2115 is positioned between the buffer flow openings 2114 and extends parallel to the longitudinal axis of the extraction lumen. In this embodiment, the navigation lumen 2115 is a reinforced flexible lumen attached to the inner wall of the extraction lumen 2116 of the aspiration catheter. The navigation lumen 2115 is configured to accommodate a navigation catheter 2117 that is compatible with a 0.035" guidewire. The positioning of the navigation lumen 2115 assists in tracking the aspiration catheter and serves as a shield to reduce the possibility of a clot entering the extraction opening 2104 and blocking the buffer flow opening 2114. In Figure 21D-Figure 21E In FIG. 2 , the infusion lumen 2115 is positioned next to the navigation lumen 2115. The infusion lumen 2118 may also be attached to the inner wall of the extraction lumen 2116. It should be understood that the lumen may also be attached to the outer wall of the catheter body. The infusion lumen 2118 may also be constructed of a flexible, lay-flat tube so that when not in use, the lumen will lie relatively flat against the wall with minimal impact on the contour or area within the extraction lumen 2116. Figure 21D-Figure 21E In the embodiment, the infusion lumen 2118 is composed of a flexible reinforced polymer tube. The distal end of the infusion lumen 2118 is positioned just proximal to the proximal edge 2108 of the extraction opening 2104. The distal end of the infusion lumen is blocked, and at least one infusion distal opening 2119 is opened through the side walls of the infusion lumen 2118 and the extraction lumen 2116, so that the infusion lumen is in fluid communication with the vascular. Fig.21F The proximal handle of the aspiration catheter is shown. Within the handle, the extraction lumen 2116 is routed to the extraction port 2116', and the infusion lumen 2118 is routed to the infusion port 2118'. The infusion lumen port 2118' can be configured to accommodate standard syringe luer locks. The navigation port 2115' is positioned between the extraction port 2116' and the infusion port 2118'. Figure 21G A cross-sectional view of the extraction lumen of the aspiration catheter is shown, illustrating how the infusion lumen 2118 and the navigation lumen 2115 are positioned within the extraction lumen 2116. Fig.21H and Fig.21IHow to connect this embodiment of the present invention and how to infuse external fluid into the vessel proximal to the buffer flow opening 2114 is shown. The external fluid chamber 2120 is connected to the infusion port 2118'. In some embodiments, the chamber is positively pressurized. In other embodiments, the chamber is passive, and when opened, the negative pressure generated by the vacuum pressure applied to the extraction chamber 2116 draws the fluid out of the chamber. Fig.21H and Fig.21I The arrows shown in show the flow of the external fluid.

[0172] Fig. 22 An example of a method of removing clotted material using a tip including one or more buffer flow openings as described herein is shown. Fig. 22 At 2201, the method may include initially positioning a distal end of an aspiration catheter proximate to the clot material. A navigation catheter (e.g., a diagnostic catheter and / or a guidewire) may be used to position a distal region of the catheter proximate to the clot material within the lumen of the vessel such that the extraction opening faces toward or proximate to the clot material (and may face away from the nearest wall of the vessel). The catheter may be rotated eccentrically around the diagnostic catheter and / or the guidewire to aid in orientation and positioning relative to the clot material and the vessel wall.

[0173] At 2203, suction can be applied through the extraction opening to draw the clot material toward the extraction opening; while the flow flowing through one or more buffer flow openings can apply rotation (e.g., rotational force) to the clot material at the extraction opening, thereby driving the clot material against the proximal edge of the extraction opening. At 2205, suction (extraction) can continue while the clot material is cut into one or more strips against the proximal edge of the extraction opening, so that the clot material is rotated and driven by the combination of the flow from the extraction opening and the buffer flow opening. At 2207, the process can continue to remove the long strand of material until the clot material is removed. The catheter can be repositioned during or after the process. Extraction can be applied continuously or can be stopped periodically to remove the clot material from the collection chamber, as described in detail below.

[0174] Buffer Flow Area

[0175] In any of the examples described herein, the operation of the extraction catheter to remove clot material (particularly large clots) by rolling and peeling the clot (as opposed to breaking the clot) can benefit from maintaining a region of buffer flow in a portion of the extraction tip opposite the extraction opening. The buffer flow region can be established by a buffer fluid flow as described above and / or as shown in the following examples. Fig.23A and Fig. 23BA buffer flow region 2324 is shown which can aid in the extraction of large clots, for example by rolling the clot material against the proximal edge of the extraction opening to compress and / or "peel" the clot material so that the clot material can enter the extraction lumen without clogging or forming a lollipop. Fig.23A , a buffer flow region 2324 (shown as the area within the dashed outline) is along the bottom of the suction cavity (extraction cavity) 2316 opposite the extraction opening 2304 and can be formed by the buffer flow openings 2314, 2314', 2314". When suction is applied from the proximal end through the suction cavity, fluid (e.g., blood) from the vessel can flow through these buffer flow openings in 2304, 2306, 2308. The flow can be slightly deflected by the navigation cavity 2312 passing through the suction cavity 2316. In Fig.23A In the embodiment of the present invention, the catheter can also include a contrast lumen 2312 which can terminate proximal to the extraction opening 2304 .

[0176] Fig. 23B Shows Fig.23A 23. A side view of the distal end region of the extraction catheter of FIG. 23. The region of buffer flow 2324 is shown as being within the dashed region opposite the extraction opening 2304 (e.g., on the "bottom" half of the suction chamber opposite the extraction opening). As mentioned above, this buffer flow region can be formed by fluid flow through the distally located buffer flow openings 2314, 2314'. Fig. 23B In the example shown, the distal tip region includes four buffer flow openings (two on either side of the longitudinal midline) on either side of the enclosed extraction lumen 2312 extending through the length of the device, at the "bottom" of the suction lumen. An example of a buffer flow 2364 is shown in FIG. Fig. 23B In this example, the distal end of the suction lumen at the distal tip is closed, thereby forming a vortex chamber 2322. The vortex chamber may be equivalently referred to as a holding area in this article.

[0177] In any of the devices and methods described herein, the location and size of the buffer flow opening can help establish a buffer flow area that is configured to cause the clot material to roll against the proximal end of the extraction opening, thereby preventing the clot material from breaking and enhancing capture. Generally, these methods and devices can compress the clot material and / or roll the clot material against the proximal edge of the extraction opening without significantly eroding or damaging the clot material and without clogging. Therefore, this technique for extracting and extending the clot can minimize the possibility of embolism. In contrast, as described above, these methods and devices cut off long strips of clot material and / or change the shape of the clot material to present long strips without significantly breaking the clot material.

[0178] exist Figure 23A-23BIn the method and apparatus, the buffer flow area can be generated by the relative arrangement of the buffer flow opening and the extraction opening. In any of these methods and apparatuses, the ratio of the buffer flow opening (total buffer flow opening) to the extraction opening may be between about 5% and about 10% (e.g., between about 6% and 9%, between about 7% and 8%, etc.). The ratio of the buffer flow opening to the extraction chamber cross-section may be, for example, between about 5% and about 15% (e.g., between about 8% and 13%, between about 10% and 12%, etc.). Each individual buffer flow opening may be about 1%-3% (e.g., about 2%) of the cross-sectional size of the suction chamber. As discussed and illustrated above, the offset positioning of the buffer flow opening relative to the extraction opening may also be particularly beneficial.

[0179] In any of the devices described herein, the positioning of the extraction lumen relative to the long axis of the catheter (and in particular, relative to the extraction lumen) can significantly enhance the buffered flow effects described herein. For example, any of these devices can include an extraction orifice 2404, which can be generally positioned on the tapered outer side of the catheter, such as Fig.24A As shown, the distal-most edge of the extraction opening does not pass through the longitudinal centerline 2450 of the extraction cavity. Fig.24A The positioning of the orifice centerline 2452 is shown, which is a line extending through the longitudinal center of the extraction orifice 2404 and parallel to the long axis of the midline of the extraction chamber 2450. In some examples, the farthest side and edge of the extraction opening are on the tapered side of the suction chamber, but the extraction opening does not extend beyond about half (e.g., between 40% and 60%) of the transverse diameter of the suction chamber. The offset extraction orifice can bias the clot entrainment toward the side of the shaft (extraction catheter) opposite to the buffer flow opening. The buffer flow region 2424 can extend from a more distal region toward a more proximal direction, where the direction of the flow is angled relative to the direction of the clot entering the extraction opening (e.g., between about 90 degrees and 160 degrees, between about 100 degrees and about 150 degrees, etc.). This can allow the buffer flow openings 2414, 2414' to increase their flow rate when the extraction orifice begins to become blocked by clots, helping to prevent blockage and imparting a rotational force on the clot to rotate the clot against the proximal edge of the extraction opening. The distal edge of the extraction opening can be at or slightly above the midline of the extraction lumen 2450. This configuration can also prevent clot material from blocking or forming a lollipop.

[0180] Figure 24B1-Figure 24B2 , Fig. 24C1-Fig. 24C2 and Figure 24D1-Figure 24D2An example of a device is shown in which the extraction orifice extends on the tapered side of the extraction conduit such that the diameter of the extraction lumen measured at the distal edge of the extraction opening 2404 extends at least 40% (e.g., 45%, 50%, 55%, 60%, etc.) of the diameter of the extraction lumen measured at the proximal edge of the extraction opening. Figure 24B1 A side view of a device is shown with an extraction opening 2404 extending approximately 40% of the diameter of the suction lumen; the diameter of the suction lumen measured at the distal edge of the extraction opening 2404 extends 60% of the diameter of the suction lumen measured at the proximal edge of the extraction opening. Figure 24B1 , longitudinal centerline 2450 is shown as a dashed line, while line 2455 extending from the distal edge of the extraction opening is shown as a solid line. Figure 24B1 Also shown is the distance between the midline and the distal edge 2444, as well as the radial distance 2446 from the proximal edge of the extraction opening to the distal edge of the extraction opening, which is approximately 40% of the diameter of the suction lumen. Figure 24B2 Shows Figure 24B1 24, showing the extraction opening 2404 and showing how far the extraction opening extends radially into the suction lumen. The extraction opening extends about 40% of the diameter of the suction lumen (eg, from the top edge of the suction lumen). Fig.24C1 2404' that extends approximately 50% of the diameter of the aspiration lumen (transverse to the long axis of the aspiration lumen); the diameter of the aspiration lumen measured at the distal edge of the aspiration opening 2404' extends 50% of the diameter of the aspiration lumen measured at the proximal edge of the aspiration opening. Fig.24C1 , the longitudinal centerline 2450 of the suction lumen is shown as a dashed line, while line 2444' extends from the distal-most edge of the extraction opening (shown as a solid line). Fig.24C1 Also shown is the distance between the midline and the distal edge 2455', as well as the radial distance 2446' from the proximal edge of the extraction opening to the distal edge of the extraction opening, which is approximately 50% of the diameter of the extraction lumen. Fig.24C2 Shows Fig.24C1 24 , showing the extraction opening 2404 'and showing how far the extraction opening extends radially into the suction cavity. In this example, the extraction opening extends about 50% of the diameter of the suction cavity (eg, from the top edge of the suction cavity). Fig.24D1 2404'" which extends approximately 60% of the diameter of the suction lumen (transverse to the long axis of the suction lumen); the diameter of the suction lumen measured at the distal edge of the extraction opening 2404' extends 40% of the diameter of the suction lumen measured at the proximal edge of the extraction opening. Fig.24D1, the longitudinal centerline 2450 of the suction chamber is shown as a dotted line, which is spaced apart from a line 2444", which extends from the farthest edge of the extraction opening (shown as a solid line). Fig.24D1 Also shown is the distance between the midline and the distal edge 2455", as well as the radial distance 2446" from the proximal edge of the extraction opening to the distal edge of the extraction opening, which is approximately 60% of the diameter of the suction lumen. Fig.24D2 Shows Fig.24D1 24 is a distal end view of a device showing an extraction opening 2404" and showing how far the extraction opening extends radially into the suction lumen. In this example, the extraction opening extends approximately 60% of the diameter of the suction lumen (e.g., from the top edge of the suction lumen).

[0181] In practice, when the diameter of the suction lumen measured at the distal edge of the extraction opening extends 40% or more (e.g., 45% or more, 50% or more, 55% or more, 60% or more, etc.) of the diameter of the suction lumen measured at the proximal edge of the extraction opening, the suction catheter described herein can work surprisingly better, for example, forming a buffer flow region opposite the extraction opening, as described and demonstrated above. This configuration of the extraction opening and the suction lumen can leave an area of ​​the diameter of the suction lumen (opposite the extraction opening) that is separated from the flow entering the suction lumen through the large extraction opening; this separated area can form Figure 23A-23B The flow in this region may be the result of flow into the aspiration chamber through the buffer flow opening, which may cause rotational forces on the clot material within the aspiration opening, thereby driving the rotation and cutting of the clot material strip that may be aspirated as described herein.

[0182] In any of these examples, the device can be configured such that the distal tip region 2527 of the catheter connected to the aspiration lumen (extraction lumen) is closed to prevent fluid (or more likely, clot material) from entering the aspiration lumen and / or blocking the tip region. Fig.25 As shown, this can create an end retention region 2522, which can be beneficial. Fig.25 In the embodiment of the present invention, the end holding region 2522 is a dead end with a holding volume. This volume can be filled with a fluid (e.g., blood) and can redirect the flow from the distal end toward the proximal end as part of the buffer flow region. For example, in Fig.25 In the case of Fig. 23BAnd the distal end region shown in Figure 24, including the extraction opening 2504 and four offset buffer flow openings 2514, 2514' (two on either side of the guide channel in the suction chamber). In this example, the distal end region 2527 generates a terminal vortex by preventing the distal end of the distal side of the extraction opening 2504 from flowing out (acting as a "dead end"), and provides a flow barrier to bias the clot to one side of the axis where the proximal edge of the extraction opening is located. The vortex region (terminal holding region) is also used to block the flow, so that the flow from the buffer flow openings 2514, 2514' is blocked. The closed distal region can also be referred to as a shield region at the distal end of the device.

[0183] In any of these examples, the buffer flow opening can be protected or guarded by one or more structures in the suction chamber. The buffer flow opening can therefore be configured so that the flow entering the suction chamber forms a buffer flow area. Figure 23A-23B , Figure 24 and Fig.25 As shown, the buffer flow opening is adjacent to the navigation cavity (and in some cases, the contrast cavity) and is partially shielded by the navigation cavity. Fig.26 An example of a cross section through the distal region (tip region) of an extraction catheter (such as those described herein) is shown, the cross section passing through a region transverse to the extraction opening 2604. Fig.26 , the portion shows a pair of buffer flow openings 2614, 2614' adjacent to the navigation lumen 2612 (e.g., on either side of the navigation lumen 2612) extending from proximal to distal on one side of the catheter's aspiration lumen. This can protect or shield the buffer flow opening 2614 adjacent to the navigation catheter lumen 2624'. Fig.26 In the embodiment of the present invention, the contrast chamber 2612 also enters this area and can protect the buffer flow opening. Therefore, the buffer flow opening is protected from being blocked or blocked by the clot material attracted into the suction chamber. The flow entering the buffer flow opening can also be redirected by the navigation chamber and / or contrast chamber or other structure in the suction chamber 2616 to help form and maintain the buffer flow area 2624 from the fluid streams 2604, 2606, 2608 entering the buffer flow opening.

[0184] Typically, the buffer flow opening can provide a low pressure, relatively high flow rate leading to the suction chamber. These low pressure, high flow rate buffer flow openings can buffer and redirect clot material relative to the extraction opening and extraction chamber as described herein without destroying or breaking the clot material. Typically, the pressure applied by the buffer flow opening is derived from the suction applied by the suction chamber (and can be proportional to the suction applied by the suction chamber). The buffer flow opening can be any suitable size (as described above) and can be operated to maintain a relatively low pressure.

[0185] The aspiration lumen can be of any suitable diameter (e.g., about 10F or greater, 12F or greater, 14F or greater, 16F or greater, between about 6F and 30F, between 8F and 28F, between 12F and 28F, etc.). In some cases, the aspiration device can be relatively narrow and can include an aspiration lumen but not a separate navigation lumen (e.g., for navigating a catheter, a navigation shaft, a guidewire, etc.) and / or a contrast lumen.

[0186] As mentioned above, any of these devices can be configured to apply an external fluid through one or more buffer fluid openings. For example, saline can be provided from a proximal saline source and applied through one or more distal buffer fluid openings. In some cases, the fluid forming the buffer fluid region can be discharged from the internal navigation cavity and / or contrast cavity. In some examples, the external fluid can be a saline solution that can be infused into the extraction (suction) cavity. The fluid can be pumped in or can be attracted (by applying suction through the suction cavity, which can pull the external fluid from the proximal source into the suction cavity). As with any of these devices, the cavity of the device (e.g., suction cavity, navigation cavity, contrast cavity, etc.) can be primed, for example, with saline before the operation begins.

[0187] Fig.27A and Fig.27B An example using an external fluid is shown. Fig.27A In the embodiment, the contrast chamber 2712 includes one or more buffer fluid openings 2745, which can apply external fluid to form a buffer flow area on the side of the suction chamber opposite the extraction opening 2704. The contrast chamber can include a tube fixed within the suction chamber (or on one side of the suction chamber), or it can be a removable tube or member that can be inserted / removed laterally. Fig.27A In the embodiment, the distal region also includes buffer fluid openings 2714, 2714'. Fig.27A As shown, the contrast lumen can be used to deliver fluid (eg, saline) into the continuous flow region that forms the buffer flow region. In Figure 27, the distal end of the aspiration lumen is closed, but the navigation lumen 2712 also extends distally out of the device.

[0188] In some examples, a lumen (such as a contrast lumen) can be configured as a dual-purpose lumen that can both inject contrast media to the distal exterior of the device (e.g., exterior of the extraction opening 2704) and provide an external fluid to provide a buffer flow. In some examples, the shaft can be rotatable or rotatable so that the direction of an opening (e.g., a buffer flow opening 2745) can be adjusted based on whether the contrast lumen is delivering contrast media or a buffer flow.

[0189] Fig.27B An example of a device in which the navigation cavity 2712 can be configured to deliver additional buffered streams is shown. Fig.27BIn, the extraction conduit may include one or more side openings 2747. Fig.27B The illustrated aspiration catheter also includes four offset buffer flow openings 2714, 2714' and a contrast lumen 2712. In use, the device can apply suction from the suction lumen and output from the extraction opening 2704, and can also apply fluid (e.g., saline) as part of the continuous flow (when suction is applied) or as needed to help prevent clot material from blocking the extraction opening and / or to prevent clot material from blocking the extraction opening.

[0190] Figure 28A-28B Another example of an apparatus configured to apply saline as part of the buffer flow fluid is shown. The aspiration lumen can apply a continuous fluid flow from the distal region, through at least the proximal half of the extraction opening 2804 (and in some examples, from the distal half of the extraction opening or distal to the distal half of the extraction opening) to roll up and "peel off" the clot material without breaking it up, so that the clot material can be drawn into the aspiration lumen even if the clot material blocks the extraction opening.

[0191] exist Fig.28A In , device 2800 is an aspiration catheter that includes an aspiration lumen 2816 extending distally to proximally. The catheter also includes a navigation lumen (which may be referred to as a continuous flow lumen) that may be built into the shaft of the catheter or may be insertable in some examples. The navigation lumen 2812 may also be configured to allow passage of a guidewire 2811, as shown, or in some examples, a navigation catheter (not shown). In Fig.28A In the embodiment of the present invention, a guide wire is inserted through the navigation catheter and extends distally out of the distal opening 2816. In this example, the navigation lumen (continuous flow lumen) can terminate in the distal region of the distal tip before the distal end, so that the distal end 2857 of the navigation lumen is adjacent to the distal region of the extraction opening 8204, adjacent to the distal end of the extraction opening, or just distal to the distal end of the extraction opening. For example, the opening 2857 can be positioned so that it is opposite to the extraction orifice 2804 and can terminate somewhere between the proximal edge of the orifice and the region just distal to the distal edge of the extraction orifice 2804.

[0192] The distal end (distal opening 2816) of the device can be configured so that the guide wire can leave the end, but closed and / or sealed on the end of the guide wire, as shown. For example, the inner diameter (ID) of the end of the device 2816 can be configured so that the guide wire (e.g., 0.035GW) passes through the device, but it can limit the fluid flow (e.g., the saline injected) to leave the end distally. On the contrary, the fluid can leave the distal end (with or without the guide wire) and can be redirected by the interior of the distal end region so that the fluid is guided proximally and is drawn out via the vacuum applied during the clot removal.

[0193] In some examples, the distal tip 2816 can be closed by a membrane or by a pre-set "pinch" that can allow a guidewire (e.g., a 4F catheter or guidewire) to be inserted through it, but can also restrict fluid from leaving the tip. Any of these devices can also include additional buffer flow openings (in Fig.28A Not shown in the example, but present in Fig.28B middle). Fig.28B Another example of an extraction catheter 2800' is shown, in which a navigation lumen 2812 is configured to pass saline as part of a buffer flow. When suction is applied, a buffer flow can be provided through the buffer flow openings 2814, 2814' positioned as described above. In some cases, additional fluid can be applied through the navigation lumen as needed, for example, to help prevent blockage of the extraction orifice 2804 or adhesion of clot material. For example, additional saline can provide a continuous flow that can help roll and / or compress clot material to prevent blockage of the extraction orifice.

[0194] Fig.29 and Fig.30 An alternative example of an aspiration catheter is shown that includes a navigation lumen configured to deliver saline as part of the buffer flow into the distal region of the catheter, similar to Fig.28A and Fig.28B The example shown in Fig.29 , the navigation lumen 2912 extends into the distal region of the extraction catheter within the aspiration lumen such that the distal end 2957 of the navigation lumen is positioned opposite the distal end of the extraction orifice (extraction opening 2904). The guide wire 2911 is shown extending through the navigation lumen 2912 and out of the distal end 2916 of the extraction catheter. Figure 28A-28B As mentioned, the distal end 2916 can be configured to close or seal to prevent the passage of fluids, but to allow passage of a guide wire and / or a guide catheter (e.g., a navigation catheter). Fig.29 In the example, the distal region of the navigation cavity 2912 may also include one or more lateral openings (e.g., configured as buffer flow openings 2954 for allowing fluid (such as saline) to flow out of the navigation cavity and into the aspiration cavity). These one or more lateral openings (in this example, multiple small lateral openings are shown) can be oriented away from the extraction opening 2904 to better help establish a buffer flow region opposite the extraction opening 2904. In addition, as Figure 28A-28BAs shown, the distal end 2957 of the navigation lumen can also be open and allow fluid to pass when suction is applied in the aspiration lumen and / or when fluid is driven from the proximal end of the navigation lumen (by applying positive pressure) into the closed distal region 2922 and redirecting the flow proximally. Typically, one or more buffer flow openings 2954 (e.g., ports) on the navigation lumen can be configured to be cross-positioned with the distal region of the extraction opening, which is generally true for the buffer flow openings, so that they can be from the buffer flow region extending along the long axis of the aspiration lumen to drive the clot to rotate against the proximal edge region of the extraction opening.

[0195] Fig.30 Similar to Fig.29 The illustrated example includes a navigation cavity 3012 having a distal opening 3507 that is positioned distal to or opposite to the distal region of the extraction opening 2904. Fig.30 In the embodiment, one or more elongated buffer flow openings 3054 are formed through the lateral opening of the navigation catheter. Fig.29 As shown, in Fig.30 The aspiration catheter shown in FIG. 1 can be used with or without a guidewire in the navigation lumen. In general, the buffer flow opening through the navigation lumen into the aspiration lumen can have a variety of different shapes and sizes to allow fluid (e.g., saline) discharged from the navigation lumen to be dispersed in the distal end region, which is opposite to the location where the clot enters the extraction opening.

[0196] Fig.31Another example of a suction catheter is shown, in which the device is configured so that fluid can be drawn into the suction chamber from an area distal to the catheter (such as a clot distal to the catheter) through an inner cavity (e.g., similar to a navigation cavity). In this example, the suction catheter 3100 includes an extendable cavity 3159, which can extend the distal end of the suction catheter distally. The extendable cavity can draw fluid from the outside of the catheter (e.g., on the distal side of the clot) into the suction chamber and draw out ports 3154 (e.g., one or more buffer flow openings) on the outer side of the extendable cavity 3159. In some examples, the area near these ports of the extendable cavity can be closed, so that the fluid can be drawn into the suction chamber from the extendable cavity (and from the area distal to the clot in the vessel 3157) by suction of the suction chamber to form a buffer flow area adjacent to the extraction opening 3104. When the extraction catheter is close to the clot 3155, the extendable cavity can be advanced distally out of the extraction catheter so that the lateral buffer flow opening is positioned adjacent to the distal end of the extraction opening (or positioned slightly distal to the extraction opening). Thus, in this example, the cavity can be dynamically advanced distally of the blood clot 3155 and blood can be drawn from the distal portion of the vessel 3157 into the aspiration tip to provide the fluid required to keep the blood clot moving and the catheter flowing during extraction. As mentioned above, the proximal end of the extendable cavity is closed to ensure that fluid is pulled out of the distal opening of the extendable cavity.

[0197] Suction chamber

[0198] In addition to the catheter device described herein, a blood collection (extraction) device configured to re-perfuse the collected blood is also described. The catheter and apparatus for removing thrombus from the vascular system may include an elongated extraction catheter, such as those described above. Suction can be applied by the catheter to extract and discharge thrombus from the target site in the vascular system, through the cavity of the device, where thrombus can be collected in vitro. In some cases, extraction / suction is provided by pulling the attached syringe into a vacuum. In other configurations, extraction / suction is applied from a suction pump attached to the catheter.

[0199] Blood collection chamber devices (devices, systems, etc., including blood collection devices) are described herein, in which extracted thrombotic material and fluid blood can be collected for detection and measurement. In particular, these devices can be configured to achieve effective and safe reperfusion of collected (and filtered) blood. In some configurations, a suction pump is connected to the blood collection chamber, and the blood collection chamber is then connected to a catheter. The collection chamber may include a valve or may be connected in series with the device to selectively open a fluid path from the catheter to the chamber to allow extraction / suction to be applied directly from the catheter (e.g., an extraction catheter). The blood collection chamber described herein may alternatively be referred to as a vacuum chamber, a vacuum accumulator, a vacuum box, or a vacuum reservoir.

[0200] The blood collection chamber can be configured to allow direct visualization of the clot and / or blood collected. For example, all or part of the blood collection chamber can be formed by clear (transparent or at least translucent) material so that the collected blood and / or thrombus can be visualized. Any of these devices can be calibrated to indicate the volume of the collected blood and / or thrombus. For example, the device can include a scale (e.g., a mark) to allow the volume of the extracted material to be measured. Any of these devices can include one or more filters (e.g., a coarse filter and / or a fine filter) to separate the fluid blood from the collected solid-semisolid thrombus. The filter can be removable, particularly a coarse filter, so that the filtered thrombus can be removed, cleaned (e.g., rinsed with saline), measured, photographed and / or physically examined by a doctor or used for further testing.

[0201] Typically, these devices can be configured to be sized to collect and hold a manageable volume in a surgical area, on top of a bed rail, or on an IV pole. Additionally, these devices can have a sufficiently small volume to allow a suction pump to quickly (e.g., within a minute) reach an internal vacuum. These devices can have a sufficiently large volume to provide sufficient vacuum accumulation so that applying extraction / suction in a 5 second burst does not reduce the chamber vacuum by more than 50% or less. These devices can be appropriately sized so as not to allow excessive extraction (risking bleeding the patient). For example, these devices can be configured to limit blood removal to 500cc or less of blood. In some examples, the blood collection chamber can be approximately 500cc.

[0202] In addition, the blood collection device described herein can be configured to allow reperfusion of the collected fluid blood. Although this can be as simple as an openable cover that allows the collected fluid to be removed with a syringe and a fine filter, more specifically, the device described herein can be adapted to filter and process blood so that the blood can be used immediately and easily quickly in an operating room and near the patient (or directly connected to the patient) in a manner that prevents blood bubbling and / or interference. In some examples, the filtered blood can be configured to be drawn from the bottom side wall via an unnecessary syringe valve. This can allow fluid blood to be drawn from the blood collection device by a syringe for reperfusion to the patient through a blood return circuit placed in the vascular system. In some cases, the blood return circuit can be directly connected to the device.

[0203] Any of these devices can be illuminated to enhance visualization of blood and / or removed clots. Any of these devices can include a separate clot collection chamber in series with the device. The device, particularly the clot collection portion (which can include a coarse filter), can be configured to measure the weight and / or volume of clot material collected.

[0204] Any of these devices can be heated and / or cooled. In particular, the area of ​​the device configured for collecting blood can be temperature-regulated. As described in detail below, the device can generally include an upper chamber, which is configured to be filled with vacuum and connected in series with an extraction conduit, and the upper chamber is fluidically connected to a lower blood collection area, which is configured to be communicated with the reperfusion part. Blood can generally be configured to be transferred between an upper chamber (upper tank or vacuum chamber) and a lower chamber (lower tank or blood collection chamber) by gravity. In some examples, the upper chamber and the lower chamber can be formed by the same (or different) tank, and can be separated by one or more passive or active valves, which maintain the negative pressure (e.g., vacuum) in the upper chamber, and only when the pressure between the two chambers is standardized in a manner to prevent or limit blood bubbling, blood is transferred to the lower chamber.

[0205] Any of these blood collection devices can be configured to allow the introduction of medications, such as heparin. Any of these devices can be configured to allow saline flushing. In some examples, the device can include one or more sealable but openable covers or doors, or allow manual emptying and / or cleaning of the contents.

[0206] Typically, these devices can be configured to operate safely and provide a fail-safe mode, including one or more automatic or self-closing valves such that when the blood collection chamber reaches a critical collection volume of collected blood, the extraction through the catheter into the device is stopped. This can include the use of sensors, including mechanical sensors and / or electrical sensors. In some examples, the device can include a float valve that blocks the extraction outlet when the contents position the float valve near the extraction outlet.

[0207] In general, there is an unmet need for a blood collection device having a vacuum chamber that allows blood to be collected and refilled into a patient. Currently available blood collection chambers typically collect blood in the same chamber as the vacuum. This may result in degassing and bubbling of the collected blood. This may also result in some degree of hemolysis. In addition, this may require a larger volume of the vacuum chamber, requiring longer time to fill the chamber before and between uses. The blood collection device described herein may be particularly useful for collecting blood into a vacuum chamber while minimizing the vacuum level applied to the blood and / or the time the blood remains under vacuum. The blood collection device described herein may also be configured to allow blood to be stored in a vacuum tank so that the blood can be effectively refilled and with minimal risk of damage to the blood or injury to the patient.

[0208] Fig.32 An example of a blood collection device configured for reperfusion is shown. In this example, the blood collection device is configured for use with a thrombus extraction catheter, such as (but not limited to) Figure 1 - The extraction (e.g., suction) catheter depicted in FIG. 21. Fig.32In the embodiment, the device may optionally include a vacuum source (e.g., a vacuum pump 3221) that can be connected to a vacuum line 3219. In this example, the vacuum line 3219 is connected to an outlet on a vacuum tank 3225 via a vacuum outlet 3218. The vacuum tank 3225 has a vacuum release valve 3217 (a valve that selectively opens / closes the valve to the atmosphere). In this example, the tank 3225 is divided into an upper chamber portion 3241 and a lower chamber portion 3243, which are separated by a permeable solid / liquid filter 3223, dividing the tank 3225 into an upper portion and a lower portion. Solids can be collected on the top of the filter. Fluids can pass through the filter and be collected in the bottom portion of the tank. The tank has an extraction inlet 3215. An extraction line 3211 is connected to the extraction inlet. An on / off valve 3213 is present on the extraction line (or at the extraction inlet). The extraction line can be connected to an extraction catheter inserted into the vasculature and positioned at the target / treatment site. The device also includes a reperfusion valve 3227 at the bottom and / or bottom sidewall of the canister (which can be connected to or form part of the reperfusion outlet). The reperfusion line in communication with the fluid collection bottom portion of the canister can be connected to a reperfusion circuit or collection / delivery container (e.g., bag, syringe, etc.). Fig.32 In the embodiment, the reperfusion line 3231 is connected to the reperfusion valve (and can be connected to the blood return circuit) and is also connected in series with a fine filter that can be used to further remove blood impurities.

[0209] In some examples, such as Figure 33A-Figure 33E As shown, by first turning on the pump (vacuum source 3321) and "filling" the tank 3225 to a vacuum at a desired vacuum level (e.g., less than 1 atm), e.g. Fig.32 The blood collection device shown in can be used with a suction catheter ( Fig.33B Alternatively, the vacuum may remain on, but at a reduced level, and / or may be configured to maintain the vacuum at a predetermined level within the canister; either of these devices may include a sensor to detect the pressure within the upper region of the canister. At the start of the procedure, the canister may first be emptied of all solids and fluids ( Fig.33A Once filled, the pump can be turned off, maintaining the filled vacuum in the canister. Once the extraction catheter is positioned at the target site in the vasculature, the extraction valve 3313 can be opened, and fluid blood 3343 and thrombotic material (clot material) 3344 can be drawn out of the vasculature through the extraction catheter and extraction line and into the canister ( Fig.33C ). Clotted material 3344 from the extraction conduit can collect on top of the extraction filter (e.g., coarse filter) 3323, while fluid (e.g., blood 3343) can pass through the filter and collect in the bottom portion of the canister, such as Fig.33DAs shown. At various times during the procedure, the extraction can be reduced or turned off by closing the extraction valve 3313. The extraction can be repeated until the physician removes all desired thrombi, or until the canister reaches its maximum fill point, or the maximum amount of fluid blood has been extracted, or until the canister reaches its maximum holding state, or until the "vacuum fill" in the canister is depleted to a minimum level. Once the procedure is complete, and / or once it is determined to stop or pause the extraction, the extraction valve 3313 can be closed, and the blood intended for reperfusion, now stored under vacuum conditions in the bottom of the canister, can be ready for reperfusion. For example, the vacuum release valve 3317 can be opened to reduce the canister vacuum to a minimum amount or return it to full atmospheric conditions ( Fig.33E ). Thereafter, the reperfusion valve 3327 can be opened and the collected fluid blood can be returned to the patient. The reperfusion valve 3327 can then be closed and the solid clot material 3344 can be removed (e.g., in this example, an optional cover or door can be opened to allow removal of solid thrombus and / or a solid / fluid filter with thrombus). For example, the thrombus (clot material) can be flushed with saline, inspected, measured, and cleared from the coarse filter 3323. The filter can be replaced and the cover or door closed. The vacuum release valve 3317 can then be closed and the suction pump can refill the vacuum in the canister and the physician can perform an additional extraction thrombectomy.

[0210] As mentioned above, in some cases, the suction pump 3321 can remain in continuous operation until the atmospheric valve is opened. In some cases, the atmospheric valve can be selectively opened to minimize the amount or time of maintaining fluid blood under vacuum conditions.

[0211] Often it will be particularly useful to separate the vacuum canister into separate vacuum and blood collection sections. For example, Fig.32 and Figure 33A-Figure 33E The device may include an additional partition after the coarse filter. The partition may divide the canister into an upper chamber or vacuum chamber and a lower chamber or blood storage chamber. The partition may include one or more one-way valves that allow fluid blood to pass when opened so that fluid blood can be transferred from the vacuum chamber to the blood storage chamber. The one-way valve may be configured to operate automatically (e.g., spontaneously) and / or may be controlled to open.

[0212] In some examples, the bottom chamber (e.g., blood storage chamber) may include a pressure regulating opening. In some examples, the pressure regulating opening is a small hole or opening open to the atmosphere. In some examples, the pressure regulating opening may be a valved opening that allows the pressure in the lower chamber to be controlled. Therefore, the device may include one or more sensors for detecting the pressure in the lower chamber. A one-way valve (which may be referred to as a separation valve in this article) is usually positioned on a partition between the upper chamber and the lower chamber. In some examples, the separation valve may be automatically operated by allowing fluid blood to enter the lower chamber from the upper (vacuum) chamber above via the deadweight of the fluid, which may cause the one-way valve to bend and open. When the upper chamber (vacuum chamber) is filled with vacuum and the lower chamber is open to the atmosphere, the one-way valve may remain closed due to the pressure difference between the bottom chamber at atmospheric pressure and the upper chamber under vacuum.

[0213] For example, Fig.34 An example of a blood collection device comprising a canister partitioned into an upper chamber 3441 for maintaining a vacuum and a lower chamber 3443 for maintaining filtered blood is shown. Fig.32 As shown in , the device can include or be configured to be connected to a vacuum source 3421 that applies a vacuum to fill an upper (vacuum) chamber 3441. The vacuum source can be connected to the upper chamber via a vacuum line 3419, which is connected to the upper chamber via a vacuum outlet 3418. The upper (e.g., vacuum) chamber can also include a vacuum release valve 3417 and can be filled with vacuum by the vacuum source. The upper chamber can also be connected to an extraction line connected to an extraction conduit. In Fig.34 In, the extraction pipeline can be connected to the upper chamber through the extraction inlet 3415, and the vacuum applied to the suction conduit can be adjusted by the extraction inlet valve 3413.

[0214] The coarse filter 3423 can be connected in series with the upper chamber 3441. Fig.34 In the example shown, a coarse filter 3423 is located in the upper chamber. In some examples, the coarse filter is connected in series with the extraction line before the upper chamber. The apparatus also includes a partition 3442 that separates the upper chamber from the lower chamber. Fig.34 In the example shown, the diaphragm includes a separation valve 3433, which is a one-way valve that can be configured to automatically open when the pressure between the upper chamber and the lower chamber is normalized and when blood is present in the upper chamber. In some examples, the separation valve can be controlled to open (or manually opened), for example, by a controller that determines when blood is present in the upper chamber and can cause the pressure in the upper chamber and the lower chamber to normalize. For example, the controller (blood collection controller) can control the vacuum release valve 3417, the vacuum pump (or vacuum pump valve, Fig.3434, between the vacuum source 3421 and the vacuum outlet 3418) and the opening of the pressure regulating opening 3445 on the lower chamber. The lower chamber can be slightly larger than the upper chamber (e.g., the upper chamber can have a volume of about 400 ml, while the lower chamber has a volume of about 500 ml, etc.)

[0215] The lower blood collection chamber 3443 may include a pressure regulating opening 3445, as described above; in some examples, the pressure regulating opening is an opening to atmosphere. The lower chamber may also be fluidly connected to a refill valve 3477, which connects the lower chamber to a refill line 3431. A fine filter 3429 may be within the lower chamber or in series with the lower chamber (e.g., in series with the refill line).

[0216] For example, aspiration thrombectomy can be performed as described above using a blood collection device for reperfusion similar to Fig.34 34. The embodiment shown. In this example, the upper chamber can be filled with a vacuum. Because the upper chamber can be relatively small (e.g., less than 400cc volume, less than 350cc volume, less than 300cc volume, less than 250cc volume, less than 200cc volume, less than 150cc volume, etc.) compared to the total volume of the device (including the volume of the lower chamber, such as 400cc volume or greater, 450cc volume or greater, 500cc volume or greater, etc.), the vacuum chamber (upper chamber) can be filled relatively quickly. The extraction inlet valve can be controlled to apply a vacuum to the catheter connected to the extraction line 3411 to remove fluid and clot material. Blood can be collected and passed through a coarse filter 3423 to collect clot material 3444. In some examples, the system can periodically standardize the pressure between the upper chamber 3441 and the lower chamber 3443 to allow blood in the upper chamber to enter the lower chamber, where the blood can be stored. For example, the device can turn off the vacuum (or prevent vacuum from being applied to the upper chamber) and open the vacuum release valve 3317. The lower chamber can be maintained at atmospheric pressure. Once the pressure in the upper and lower chambers is normalized to be approximately the same relative to the other chambers, the separation valve 3442 can be opened and blood can be transferred from the upper chamber to the lower chamber. The blood can be discharged from the upper vacuum chamber of the tank and then maintained in the bottom chamber at atmospheric pressure.

[0217] This configuration can be particularly advantageous because the vacuum portion of the tank can be minimized because there is no need to store a volume of fluid blood between reperfusions. Due to its optimized volume, the smaller vacuum chamber can be filled to a vacuum more quickly. The blood can be stored in the lower tank at atmospheric pressure, thereby minimizing the time it spends under vacuum and allowing the physician to reperfuse the blood at a time of their choosing (e.g., the blood can be removed via the reperfusion line). Prior to reperfusion, the blood at atmospheric pressure in the storage chamber can be re-aerated and de-bubbled.

[0218] The one-way valve partition valve 3442 can be configured to remain closed when partially separating the bottom (e.g., atmosphere) chamber from the upper (e.g., vacuum) chamber. With the release of some or all of the negative pressure in the vacuum chamber, the partition valve can spontaneously open under the fluid weight of the collected blood. For example, in one example, the one-way partition valve opens at a minimum hydrostatic pressure (e.g., the pressure exerted by a fluid in equilibrium at a given point within the fluid due to gravity).

[0219] The fluid static pressure can be minimal and below a fluid height of, for example, 5 mmHg. In some embodiments, the fluid static pressure that opens the one-way valve (e.g., a "bursting pressure") can be higher than the fluid static pressure required to keep the one-way partition valve open. This will allow for a more complete evacuation of the fluid blood. In some embodiments, the one-way partition valve is configured to open under the fluid weight of the blood, even if there is some partial vacuum in the vacuum canister.

[0220] Examples of various one-way valves and how they can be used as divider valves are shown in the following table (Table 4). In Table 4, the divider valves are umbrella valves of various diameters and with various drainage hole patterns.

[0221] Table 4

[0222]

[0223] In this example test, Configuration #2 showed the best performance in terms of coupling burst pressure to drainage rate. Figure 35A-Figure 35B An example of an umbrella valve as described herein is shown. Fig.35A , the valve is shown closed. Fig.35B An open valve is shown, when the force pushing down on the valve due to the weight of the blood in the upper chamber (arrow) exceeds the bursting pressure of the valve, the valve will open and blood can flow downward. Note that if the pressures between the upper and lower chambers are not normalized (approximately equal), the valve will not open.

[0224] Figure 36A-Figure 36E Shows something like Fig.34In this example, the device includes an upper chamber 3441 and a lower chamber 3443, and the upper chamber (vacuum chamber) can be first filled with vacuum (vacuum source 3421) by turning on the pump (vacuum source 3421) and "filling" the upper chamber 3441 to a desired vacuum level (e.g., less than 1 atm). Fig.36B Once charged, the vacuum can be turned off, or alternatively, the vacuum can remain on, albeit at a reduced level or (via a valve) away from the vacuum chamber. Either of these devices can include a sensor for detecting the pressure within the upper chamber, which can be used to control feedback. At the beginning of the procedure, the upper and lower chambers can first be emptied of all solids and fluids ( Fig.36A Once filled, the pump can be turned off, maintaining the vacuum in the upper chamber. Once the extraction catheter is positioned at the target site in the vasculature, the suction valve 3413 can be opened, and fluid blood 3443 and thrombotic material (clot material) 3444 can be drawn out of the vasculature through the extraction catheter and extraction line and into the upper chamber ( Fig.36C ). Clotted material 3444 from the extraction catheter can collect on top of the extraction filter (e.g., coarse filter) 3423, while fluid (e.g., blood 3443) can pass through the filter and temporarily collect in the bottom of the upper chamber, as shown. Fig.36D At various times during surgery, the extraction can be reduced or turned off by closing the extraction valve 3413, and the pressure between the upper chamber and the lower chamber can be normalized. For example, if the lower chamber includes an opening to atmosphere (e.g., a pressure regulating opening), the vacuum release valve 3417 can be opened to set both the upper chamber and the lower chamber to approximately the same pressure (e.g., atmospheric pressure). This can allow the separation valve 3433 to be opened, as shown. Fig.36E As shown, the blood in the upper chamber can be drained (by gravity) into the lower chamber for storage. Once drained, the partition valve can be closed again, and the upper chamber can be filled with vacuum again, and extraction can continue. At any time thereafter, including when extraction is being performed or applied, blood can be removed from the lower chamber via the refill line 3431, for example by opening the refill valve 3427.

[0225] The extraction can be continued by repeating the above steps. Once the procedure is completed, and / or once it is determined to stop or pause the extraction, the vacuum release valve 3417 can be opened and the solid clot material 3444 can be removed (e.g., in this example, an optional cover or door can be opened to allow the removal of solid thrombi and / or solid / fluid filters with thrombi). For example, the thrombi (clot material) can be rinsed with saline, inspected, measured, and cleared from the coarse filter 3423. The filter can be replaced and the cover or door closed. The vacuum release valve 3417 can then be closed, and the suction pump can refill the vacuum in the canister, and the physician can perform additional extraction thrombectomy.

[0226] Fig.37 Another example of a schematic diagram of an apparatus for collecting blood for reperfusion is shown, the apparatus being similar to Fig.34 The device shown in . This example also includes a tank divided into an upper chamber 3741 and a lower chamber 3743 separated by a partition and a separation valve 3733, however, in this example, the coarse filter is part of a separate clot filtration (coarse filtration) chamber 3757, which is connected in series and upstream of the upper chamber 3741. The clot filtration chamber can be configured (e.g., in a planar configuration) to allow direct visualization of the clot material 3744 as it is filtered, and can be connected distally to an extraction line 3711 connected to an aspiration catheter, and proximally to an extraction inlet 3715 (or inlet valve 3713) of the upper chamber 3741. The filtration chamber 3757 can be opened to allow removal of clot material from the coarse filter without destroying the device. Fig.37 The device in also includes a refill valve 3727 and a refill line 3731 and a separation valve 3733 and a diaphragm 3742 between the upper chamber and the lower chamber. The vacuum source 3721 can optionally be connected to the upper chamber through a vacuum outlet 3718. The upper chamber can also include a vacuum release valve 3717.

[0227] In use, such as Fig.34 and Fig.37 The blood collection device shown can be used as described above. For example, Fig.38A method of reperfusing blood during a clot removal process is schematically illustrated. In this example, at 3802, an upper chamber of a reperfusion system can be filled with vacuum (e.g., to a desired negative pressure / vacuum), for example, by opening a vacuum source and opening a vacuum valve to couple the vacuum source to the upper chamber. At 3804, once the upper chamber is filled with vacuum, an extraction conduit (e.g., a suction conduit) can be used to remove clot material (and blood) by opening an extraction valve between the extraction conduit and the upper channel. At 3806, as the clot material is removed, it can be filtered from the blood by a coarse filter in series with the upper chamber or within the upper chamber. At 3808, at any time during the process, blood can be transferred from the upper chamber to the lower blood storage chamber by normalizing the pressure between the upper chamber and the lower chamber. For example, both the upper chamber and the lower chamber can be normalized to atmospheric pressure, for example, by opening a vacuum release valve in the upper chamber and a pressure regulating opening in the lower chamber (which can be constantly open or can be opened / closed). Once the pressure is normalized, the dividing valve between the two can be opened, allowing blood to drain between the upper and lower chambers; then, at 3812, the dividing valve can be closed and the upper chamber can be filled again, allowing the extraction procedure to continue, repeating the steps of extracting and then draining blood from the upper chamber to the lower chamber. At 3810, the collected blood can be kept warm or cooled and kept at atmospheric pressure so that it can degas; at any point, the collected blood can be withdrawn through the reperfusion line and returned to the patient's body.

[0228] It should be appreciated that all combinations of the foregoing concepts and additional concepts discussed in greater detail below (provided such concepts are not mutually inconsistent) are contemplated as being part of the inventive subject matter disclosed herein and can be used to achieve the benefits described herein.

[0229] The process parameters and order of the steps described and / or illustrated herein are given as examples only and may be varied as desired. For example, although the steps illustrated and / or described herein may be shown or discussed in a particular order, the steps do not necessarily need to be performed in the order illustrated or discussed. The various example methods described and / or illustrated herein may also omit one or more of the steps described or illustrated herein, or include additional steps in addition to the steps disclosed.

[0230] Any of the methods described herein (including user interfaces) may be implemented as software, hardware, or firmware, and may be described as a non-transitory computer-readable storage medium storing a set of instructions that can be executed by a processor (e.g., a computer, a tablet, a smartphone, etc.), which, when executed by the processor, causes the processor to control the execution of any steps, including but not limited to: display, communication with a user, analysis, modification of parameters (including timing, frequency, intensity, etc.), determination, reminders, etc. For example, any method described herein may be performed at least in part by a device including one or more processors having a memory storing a non-transitory computer-readable storage medium that stores a set of instructions for the process of the method. The various exemplary methods described and / or illustrated herein may also omit one or more of the steps described or illustrated herein, or include additional steps in addition to the disclosed steps. In addition, the steps of any method as disclosed herein may be combined with any one or more steps of any other method as disclosed herein. The processor as described herein may be configured to perform one or more steps of any method disclosed herein. Alternatively or in combination, the processor may be configured to combine one or more steps of one or more methods disclosed herein.

[0231] When a feature or element is referred to herein as "on another feature or element", it may be directly on another feature or element, or there may also be intermediate features and / or elements. On the contrary, when a feature or element is referred to as "directly on another feature or element", there are no intermediate features or elements. It will also be understood that when a feature or element is referred to as "connected", "attached" or "coupled" to another feature or element, it may be directly connected, attached or coupled to another feature or element or there may be intermediate features or elements. On the contrary, when a feature or element is referred to as "directly connected", "directly attached" or "directly coupled" to another feature or element, there are no intermediate features or elements. Although described or shown with respect to one embodiment, the features and elements described or shown in this way may be applied to other embodiments. Those skilled in the art will also recognize that references to structures or features that are arranged to be "adjacent" to another feature may have overlapping or portions located below adjacent features.

[0232] The terms used herein are only used for the purpose of describing specific embodiments and are not intended to limit the present invention. For example, as used herein, the singular forms "a", "an", and "the" are also intended to include the plural forms, unless the context clearly indicates otherwise. It will be further understood that when used in this specification, the terms "comprises" and / or "comprising" specify the presence of the features, steps, operations, elements, and / or parts, but do not exclude the presence or addition of one or more other features, steps, operations, elements, parts, and / or combinations thereof. As used herein, the term "and / or" includes any and all combinations of one or more of the relevant listed items and may be abbreviated as " / ".

[0233] For ease of description, spatially relative terms such as "under", "below", "lower", "over", "upper" and the like may be used herein to describe the relationship of one element or feature to another element or feature as illustrated in the accompanying drawings. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the accompanying drawings. For example, if the device in the drawings is reversed, such as an element is described as "below" or "beneath" other elements or features, the element would be oriented "over" other elements or features. Thus, the exemplary term "below" would encompass both orientations of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly. Similarly, the terms "upwardly", "downwardly", "vertical", "horizontal", etc. are used herein for explanation purposes only unless otherwise specifically stated.

[0234] Although the terms "first" and "second" may be used herein to describe various features / elements (including steps), these features / elements should not be limited by these terms unless the context indicates otherwise. These terms may be used to distinguish one feature / element from another feature / element. Therefore, without departing from the teachings of the present invention, the first feature / element discussed below may be referred to as the second feature / element, and similarly, the second feature / element discussed below may be referred to as the first feature / element.

[0235] In this specification and the appended claims, unless the context requires otherwise, the term "comprise" and variations thereof such as "comprises" and "comprising" mean that various components can be used together in methods and articles (e.g., compositions and apparatus, including devices and methods). For example, the term "comprising" will be understood to imply the inclusion of any stated elements or steps but not the exclusion of any other elements or steps.

[0236] In general, any of the devices and methods described herein should be understood to be inclusive, but all or a subset of components and / or steps may alternatively be exclusive and may be expressed as "consisting of" or alternatively "consisting essentially of" the various components, steps, sub-components or sub-steps.

[0237] As used herein in the specification and claims, including in the examples, and unless otherwise expressly stated, all numbers can be read as if beginning with the word "about" or "approximately", even if the term does not appear explicitly. The phrase "about" or "approximately" can be used when describing the amplitude and / or position to indicate that the value and / or position described are within the reasonable expected range of the value and / or position. For example, the numerical value can have a value of + / -0.1% of the stated value (or range of values), + / -1% of the stated value (or range of values), + / -2% of the stated value (or range of values), + / -5% of the stated value (or range of values), + / -10% of the stated value (or range of values), etc. Any numerical value given herein should also be understood to include about or approximately the value, unless the context otherwise indicates. For example, if the value "10" is disclosed, then "about 10" is also disclosed. Any numerical range listed herein is intended to include all subranges contained therein. It should also be understood that when a value is disclosed, "less than or equal to" the value, "greater than or equal to" the value, and possible ranges between values ​​are also disclosed, as appropriately understood by those skilled in the art. For example, if the value "X" is disclosed, "less than or equal to X" and "greater than or equal to X" are also disclosed (e.g., where X is a numerical value). It should also be understood that throughout the application, data is provided in a variety of different formats, and that the data represents endpoints and starting points and ranges for any combination of data points. For example, if a specific data point "10" and a specific data point "15" are disclosed, it should be understood that greater than, greater than or equal to, less than, less than or equal to, and equal to 10 and 15, and between 10 and 15 are considered disclosed. It should also be understood that every unit between two specific units is also disclosed. For example, if 10 and 15 are disclosed, 11, 12, 13, and 14 are also disclosed.

[0238] Although various illustrative embodiments are described above, any of several changes may be made to the various embodiments without departing from the scope of the invention as described in the claims. For example, in alternative embodiments, the order in which the various described method steps are performed may generally be changed, and in other alternative embodiments, one or more method steps may be skipped together. Optional features of the various device and system embodiments may be included in some embodiments and not included in other embodiments. Therefore, the foregoing description is provided primarily for exemplary purposes and should not be construed as limiting the scope of the invention as set forth in the claims.

[0239] The examples and descriptions included herein show specific embodiments in which the subject matter can be practiced by way of illustration and not limitation. As mentioned, other embodiments can be utilized and derived therefrom so that structural and logical replacements and changes can be made without departing from the scope of the present disclosure. For convenience only, such embodiments of the inventive subject matter may be referred to herein individually or collectively by the term "invention", and if in fact more than one is disclosed, it is not intended that the scope of the present application is actively limited to any single invention or inventive concept. Therefore, although specific embodiments have been illustrated and described herein, any arrangement that is considered to achieve the same purpose may replace the specific embodiments shown. The present disclosure is intended to cover any and all modifications or variations of various embodiments. After reading the above description, those skilled in the art will understand the combination of the above embodiments and other embodiments not specifically described herein.

Claims

1. A suction catheter device, comprising: an elongated body having a suction chamber; a distal region extending from the elongated body, the distal region having an extraction opening extending along a tapered length of a side of the distal region; and one or more buffer flow openings through a side of the distal region opposite the extraction opening, wherein the one or more buffer flow openings collectively have a geometric center along the length of the side of the distal region that is within + / - 20% of the longitudinal center of the extraction opening, The one or more buffer flow openings are configured to exert a rotational force on the clot material to drive the clot material against the proximal edge of the extraction opening to cut an elongated strip from the clot material and entrain the elongated strip so that the elongated strip is pulled proximally within the suction cavity.

2. The device according to claim 1, wherein: The common geometric center of the one or more buffer flow openings is within + / - 10% of the longitudinal center of the extraction opening.

3. The device according to claim 1, wherein: The common geometric center of the one or more buffer flow openings is located at or distal to the longitudinal center of the extraction opening.

4. The device according to claim 1, wherein: At least one of the one or more buffer flow openings is distal to the longitudinal center of the extraction opening.

5. The device according to claim 1, wherein: The one or more buffer flow openings include between 2-20 buffer flow openings.

6. The device of claim 1 further comprising a shield extending from an outer surface of the elongated body opposite the extraction opening and distal to the buffer flow opening, wherein the shield is configured to prevent clot material from entering the buffer flow opening.

7. The device according to claim 1, wherein: The one or more buffer flow openings are positioned between 60 and 120 degrees from a longitudinal centerline through the extraction opening.

8. The device of claim 1 further comprising a navigation lumen extending along the distal region adjacent to the aspiration lumen opposite the extraction opening.

9. The device according to claim 8, wherein: The one or more buffer flow openings extend through the navigation cavity.

10. The device according to claim 8, wherein: The one or more buffer flow openings include two or more buffer flow openings arranged on both sides of the navigation cavity.

11. The device according to claim 1, wherein: A ratio between an area of ​​the extraction opening and a combined area of ​​the one or more buffer flow openings is between 10:1 and 16:

1.

12. The device according to claim 1, wherein: A ratio between an area of ​​the extraction opening and a combined area of ​​the one or more buffer flow openings is between 12:1 and 14:

1.

13. The device of claim 1, further comprising a displacement protrusion extending from an outer surface of the distal region, the displacement protrusion being configured to displace an outer opening of the one or more buffer flow openings from a wall of a vessel into which the distal region is inserted.

14. The device according to claim 1, wherein: The extraction opening comprises a reinforced lip region surrounding at least the proximal edge of the extraction opening.

15. The device according to claim 1, wherein: The extraction opening is configured such that a diameter of the suction lumen at a distal edge of the extraction opening is 40% or more of a diameter of the suction lumen at the proximal edge of the extraction opening.

16. A suction catheter device, comprising: an elongated body having a suction chamber; a distal region extending from the elongated body, the distal region having an extraction opening extending along a tapered length of a side of the distal region; and one or more buffer flow openings, the one or more buffer flow openings passing through a side of the distal region opposite the extraction opening and / or through a distal end of the distal region, wherein the one or more buffer flow openings collectively have a geometric center along the length of the side of the distal region, the geometric center being distal to the longitudinal center of the extraction opening, The one or more buffer flow openings are configured to exert a rotational force on the clot material to drive the clot material against the proximal edge of the extraction opening to cut an elongated strip from the clot material.

17. A suction catheter device, comprising: an elongated body having a suction chamber; a distal region extending from the elongated body, the distal region having an extraction opening extending along a tapered length of a side of the distal region; and A plurality of buffer flow openings ranging from 2 to 20, the plurality of buffer flow openings passing through a side of the distal region opposite to the extraction opening, wherein the plurality of buffer flow openings collectively have a geometric center along the length of the side of the distal region, the geometric center being located at or distal to the longitudinal center of the extraction opening, wherein the plurality of buffer flow openings are configured to exert a rotational force on the clot material to drive the clot material against a proximal edge of the extraction opening to cut an elongated strip from the clot material.

18. A suction catheter device, comprising: an elongated body having a suction chamber; a distal region extending from the elongated body, the distal region having an extraction opening extending along a tapered length of a side of the distal region; and A plurality of buffer flow openings ranging from 2 to 20, the plurality of buffer flow openings passing through a side of the distal region opposite to the extraction opening, wherein the plurality of buffer flow openings collectively have a geometric center along the length of the side of the distal region, the geometric center being located at the longitudinal center of the extraction opening or distal to the longitudinal center of the extraction opening, wherein a ratio between an area of ​​the extraction opening and a combined area of ​​the plurality of buffer flow openings is between 12:1 and 14:1, and further wherein the plurality of buffer flow openings are configured to exert a rotational force on the clot material to drive the clot material against a proximal edge of the extraction opening to cut an elongated strip from the clot material.

19. A method of removing clotted material, the method comprising: positioning an elongated extraction opening of an aspiration catheter adjacent to a clot within a lumen of a vessel, wherein the extraction opening extends over a tapered side of a distal region of the aspiration catheter, and further wherein the aspiration catheter includes one or more buffer flow openings through a side of the distal region opposite the extraction opening; Suction is applied through the suction chamber of the suction catheter to draw the clot and fluid from the extraction opening into the suction catheter and to draw fluid through the one or more buffer flow openings, wherein the one or more buffer flow openings are configured relative to the extraction opening such that fluid flow entering the suction catheter imparts a rotational force on the clot, thereby driving the clot against a proximal edge of the extraction opening, cutting the clot against the proximal edge, and flipping the clot relative to the extraction opening.

20. The method according to claim 19, wherein: Applying suction includes applying a pressure greater than 10 mmHg.

21. The method according to claim 19, wherein: Applying suction includes drawing fluid through the one or more buffer flow openings, the one or more buffer flow openings collectively having a geometric center located at a longitudinal center within 10% of a longitudinal midpoint of the extraction opening or distal to the longitudinal center.

22. The method according to claim 19, wherein: Applying suction includes drawing fluid through the one or more buffer flow openings, the one or more buffer flow openings collectively having a geometric center located at or distal to a longitudinal midpoint of the extraction opening.

23. The method of claim 19, further comprising slicing an elongated strip of clot material from the clot as the clot is driven against the proximal edge of the extraction opening and flipped relative to the extraction opening.

24. The method according to claim 19, wherein: The one or more buffer flow openings are configured to draw fluid into the aspiration conduit such that the fluid entrains a strip of clot material that is sheared off when the clot material is driven against the proximal edge of the extraction opening.

25. The method of claim 19, wherein: Applying suction through the aspiration catheter to draw fluid through the one or more buffer flow openings includes entraining flow down the length of the aspiration lumen without substantially disrupting the severed clot within the aspiration lumen.

26. The method of claim 19, wherein: Inverting the clot relative to the extraction opening includes rotating the clot within a vessel against the extraction opening of the aspiration catheter.

27. The method of claim 19, further comprising automatically shutting off or reducing suction when a clot is no longer detected adjacent the extraction opening or within the distal region.

28. A method of removing clotted material, the method comprising: positioning an elongated extraction opening of an aspiration catheter adjacent to a clot within a lumen of a vessel, wherein the extraction opening extends on a side of a distal region of the aspiration catheter, and further wherein the aspiration catheter includes one or more buffer flow openings through a side of the distal region opposite the extraction opening; Suction is applied through the suction chamber of the suction catheter to draw the clot against the proximal edge of the extraction opening of the suction catheter, while fluid is simultaneously drawn through the one or more buffer flow openings so that a strip of clot material is cut off by the proximal edge of the suction catheter, wherein the buffer flow openings are configured such that the fluid drawn into the suction catheter through the one or more buffer flow openings entrains the strip of clot material to draw the strip of clot material proximally downward along the suction catheter without substantially destroying the strip of clot material.

29. The method according to claim 28, wherein: Applying suction includes applying a pressure greater than 10 mmHg.

30. The method of claim 28, wherein: Positioning the elongated extraction opening includes spacing the one or more buffer flow openings away from a wall of the vessel.

31. The method of claim 28, wherein: Applying suction includes drawing fluid through the one or more buffer flow openings, the one or more buffer flow openings collectively having a geometric center located at a longitudinal center within 10% of a longitudinal midpoint of the extraction opening or distal to the longitudinal center.

32. The method of claim 28, wherein: Applying suction includes drawing fluid through the one or more buffer flow openings, the one or more buffer flow openings collectively having a geometric center located at or distal to a longitudinal midpoint of the extraction opening.

33. The method of claim 28, further comprising slicing an elongated strip of clot material from the clot as the clot is driven against the proximal edge of the extraction opening and flipped relative to the extraction opening.

34. The method of claim 28, wherein: The one or more buffer flow openings are configured relative to the extraction opening such that fluid flow entering the aspiration catheter imparts a rotational force on the clot, thereby driving the clot against a proximal edge of the extraction opening.

35. The method of claim 28, further comprising automatically shutting off or reducing suction when a clot is no longer detected adjacent the extraction opening or within the distal region.

36. A suction catheter device, comprising: an elongated body having a suction chamber; a distal region extending from the elongated body, the distal region having an extraction opening extending along a tapered length of a side of the distal region; and a plurality of buffer flow openings extending through a side of the distal region opposite the extraction opening, wherein at least one of the plurality of buffer flow openings is distal to a longitudinal center of the extraction opening; wherein the extraction opening is configured such that a diameter of the suction lumen at a distal edge of the extraction opening is 40% or more of a diameter of the suction lumen at a proximal edge of the extraction opening, and The plurality of buffer flow openings are configured to form a buffer flow region within the suction cavity opposite to the extraction opening to exert a rotational force on the clot material.

37. The device according to claim 36, wherein The plurality of buffer flow openings includes between 2-20 buffer flow openings.

38. The device of claim 36, further comprising a navigation channel having a lumen extending within the aspiration lumen and configured to at least partially block the plurality of buffer flow openings.

39. The device according to claim 36, wherein: The plurality of buffer flow openings are positioned between 60 and 120 degrees from a longitudinal centerline through the extraction opening.

40. The device of claim 36, further comprising a navigation lumen extending along the distal region adjacent to the aspiration lumen opposite the extraction opening.

41. The device according to claim 40, wherein One or more additional buffer flow openings extend through the navigation cavity.

42. The device according to claim 40, wherein: The plurality of buffer flow openings include two or more buffer flow openings arranged on both sides of the navigation cavity.

43. The device according to claim 40, wherein: The navigation lumen is configured to have a distal opening within the aspiration lumen proximate the distal tip region of the lumen.

44. The apparatus of claim 36, wherein: A ratio between an area of ​​the extraction opening and a combined area of ​​the plurality of buffer flow openings is between 10:1 and 16:

1.

45. The apparatus of claim 36, wherein: A ratio between an area of ​​the extraction opening and a combined area of ​​the plurality of buffer flow openings is between 12:1 and 14:

1.

46. ​​The apparatus of claim 36, wherein: The extraction opening comprises a reinforced lip region surrounding at least the proximal edge of the extraction opening.

47. The apparatus of claim 36, wherein: The extraction opening is wider at the proximal end than at the distal end.

48. The device of claim 36, further comprising a retention region at the distal end of the aspiration lumen, distal to the extraction opening.

49. A suction catheter device, the device comprising: an elongated body having a suction chamber; a distal region extending from the elongated body, the distal region having an extraction opening extending along a tapered length of a side of the distal region; and a plurality of buffer flow openings extending through a side of the distal region opposite the extraction opening, wherein at least one of the plurality of buffer flow openings is distal to a longitudinal center of the extraction opening; wherein the extraction opening is configured such that a diameter of the suction lumen at a distal edge of the extraction opening is 40% or more of a diameter of the suction lumen at a proximal edge of the extraction opening, and The multiple buffer flow openings are configured to form a buffer flow area within the suction chamber opposite to the extraction opening to exert a rotational force on the clot material, thereby driving the clot material against the proximal edge of the extraction opening to cut a strip from the clot material without breaking the clot material.

50. A device for perfusing collected blood, the device comprising: upper chamber; lower chamber; a coarse filter positioned between the upper chamber and the lower chamber, wherein the coarse filter is configured to capture clots; a vacuum inlet opening into the upper chamber and configured to be coupled to a vacuum source; an extraction inlet, the extraction inlet opening into the upper chamber, the extraction inlet being configured to be coupled to an extraction line through an extraction valve; a reperfusion outlet from the lower chamber, the reperfusion outlet being configured to be coupled to a reperfusion line through a reperfusion valve; and a vacuum relief valve in fluid communication with the upper chamber, Wherein the refill valve is configured to open when the vacuum release valve is opened.

51. The apparatus of claim 50, further comprising a fine filter in fluid communication with the refill outlet.

52. The apparatus of claim 50, wherein: The coarse filter is configured to be manually removed from the upper chamber by opening a top of the upper chamber.

53. The device of claim 50, further comprising an impermeable partition between the upper chamber and the lower chamber and a partition valve configured to form an opening through the impermeable partition.

54. The apparatus of claim 53, wherein: The one or more isolation valves include one or more umbrella valves configured to open when fluid pressure against the valve exceeds a bursting pressure.

55. The apparatus of claim 50, wherein: The lower chamber includes a pressure regulator opening.

56. The apparatus of claim 55, wherein: The pressure regulator opening is configured to vent to atmosphere.

57. The apparatus of claim 50, wherein: The upper chamber and the lower chamber are configured to allow direct visualization of blood passing through the walls of the upper chamber and the lower chamber.

58. The apparatus of claim 50, further comprising a refill fluid line in fluid communication with the refill outlet via a refill valve.

59. The apparatus of claim 50, further comprising a vacuum source coupled to the vacuum inlet.

60. The apparatus of claim 50, wherein: The refill valve is configured to open only when the vacuum release valve is open.

61. A device for perfusing collected blood, the device comprising: upper chamber; lower chamber; an impermeable partition located between the upper chamber and the lower chamber; a partition valve configured to form an opening through the impermeable partition; a vacuum inlet opening into the upper chamber and configured to be coupled to a vacuum source; an extraction inlet, the extraction inlet leading to the upper chamber; a refill outlet, the refill outlet exiting the lower chamber; and a pressure regulating opening that opens into the lower chamber, the pressure regulating opening being configured to maintain the pressure in the lower chamber greater than the pressure in the upper chamber and higher than the bubble pressure of the blood, Wherein, the separation valve is configured to open to allow blood to flow from the upper chamber into the lower chamber.

62. The device of claim 61 further comprising a coarse filter in fluid communication with the upper chamber.

63. The device according to claim 62, wherein The coarse filter is removable to allow manual removal of blood clots.

64. The device of claim 61 further comprising a clot collection and visualization chamber comprising the coarse filter and in fluid communication with the upper chamber via the extraction inlet.

65. The apparatus of claim 61, wherein: The pressure regulating opening includes an opening to atmosphere.

66. The apparatus of claim 61, wherein: The pressure regulating opening includes a valve that controllably connects the lower chamber to a source of negative pressure.

67. The device of claim 61 further comprising a vacuum release valve in fluid communication with the upper chamber.

68. The apparatus of claim 61, wherein: The one or more isolation valves include one or more umbrella valves configured to open when fluid pressure against the valve exceeds a bursting pressure.

69. The apparatus of claim 61, wherein: The upper chamber and the lower chamber are configured to allow direct visualization of blood passing through the walls of the upper chamber and the lower chamber.

70. The apparatus of claim 61 further comprising a refill fluid line in fluid communication with the refill outlet via a refill valve.

71. The apparatus of claim 61 further comprising a fine filter in fluid communication with the reperfusion line.

72. The apparatus of claim 61 further comprising a vacuum source coupled to the vacuum inlet.

73. A device for perfusing collected blood, the device comprising: upper chamber; lower chamber; an impermeable partition located between the upper chamber and the lower chamber; one or more partition valves configured to form an opening through the impermeable partition; a coarse filter in fluid communication with the upper chamber; a vacuum inlet opening into the upper chamber and configured to be coupled to a vacuum source; a vacuum release valve located in the upper chamber; an extraction inlet, the extraction inlet leading to the upper chamber; an extraction valve located between the extraction inlet and an extraction line extending from the extraction inlet; a refill outlet located in the lower chamber and configured to be in fluid communication with a refill fluid line through a refill valve; a pressure regulating opening, the pressure regulating opening opening opening into the lower chamber, the pressure regulating opening configured to maintain the pressure in the lower chamber higher than the pressure of the upper chamber and higher than the bubble pressure of the blood; and a fine filter in fluid communication with the refill line, The one or more partition valves are configured to open when the vacuum release valve is opened to allow blood to flow from the upper chamber into the lower chamber.

74. A method of reperfusing blood during a clot removal procedure, the method comprising: Fill the upper chamber of the reperfusion system with vacuum; opening an extraction valve and drawing blood from the patient into the upper chamber through the extraction inlet, and filtering clot material from the blood using a coarse filter in fluid communication with the upper chamber; collecting blood from the upper chamber in a lower chamber after filtering the clot material, wherein collecting blood from the upper chamber in the lower chamber comprises: opening a separation valve separating the upper chamber from the lower chamber when the vacuum in the upper chamber is released to approximately the pressure of the lower chamber so that blood drains from the upper chamber into the lower chamber by gravity; After the pressure in the lower chamber is at about atmospheric pressure, opening a refill valve in fluid communication with the lower chamber; and Blood is returned from the lower chamber to the patient.

75. The method of claim 74, wherein: Opening the partition valve includes controlling the partition valve to open when a pressure in the upper chamber is substantially the same as a pressure in the lower chamber.

76. The method of claim 74, wherein: Opening the partition valve includes automatically opening the partition valve when a pressure in the upper chamber is substantially the same as a pressure in the lower chamber and a weight of the fluid on the partition valve is greater than a burst pressure of the partition valve.

77. The method of claim 74, wherein: Collecting blood from the upper chamber into the lower chamber includes releasing pressure in the upper chamber by opening a vacuum release valve.

78. The method of claim 74, further comprising filtering the blood with a fine filter before returning the blood from the lower chamber to the patient.

79. The method of claim 74, further comprising removing the clotted material from the coarse filter.

80. The method of claim 74, further comprising refilling the upper chamber with a vacuum to allow further extraction after blood is collected in the lower chamber.

81. The method of claim 74, wherein: Filling the upper chamber of the reperfusion system with a vacuum includes operating a vacuum source coupled to the upper chamber through a vacuum inlet.

82. The method of claim 81 further comprising maintaining the vacuum source continuously open while opening the extraction valve, collecting blood, and opening the refill valve.

83. A method of reperfusing blood during a clot removal procedure, the method comprising: Fill the upper chamber of the reperfusion system with vacuum; opening the extraction valve and drawing blood from the patient into the upper chamber through the extraction inlet, and filtering clot material from the blood using a coarse filter in fluid communication with the upper chamber; normalizing the pressure between the upper chamber and the lower chamber; opening a separation valve separating the upper chamber and the lower chamber so that blood flows from the upper chamber into the lower chamber; refilling the upper chamber with vacuum to allow further extraction; opening a refill valve in fluid communication with the lower chamber; and Blood is returned from the lower chamber to the patient.

84. The method of claim 83, wherein: The lower chamber is maintained at atmospheric pressure.

85. The method of claim 83, wherein: The lower chamber is maintained at a pressure between the atmosphere and the bubble pressure of the blood.

86. The method of claim 83, further comprising removing the clotted material from the coarse filter.

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