Systems and methods for vascular intervention - Patents.com

Abstract

Various embodiments of an aspiration catheter configured for removing obstructions from a patient's blood vessel and associated methods are disclosed. The aspiration catheter comprises an elongate body having a reinforcing member extending along a first length of the elongate body. In some embodiments, the aspiration catheter comprises one or more of a deformer, such as a moveable deformer, a shaped distal end, and an obstruction gripper for efficiently and effectively holding and removing the obstruction to restore blood flow.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Patent Application No. 63 / 212,514, filed June 18, 2021, and entitled "SYSTEMS AND METHODS FOR VASCULAR INTERVENTION," which is hereby incorporated by reference in its entirety. [Background technology]

[0002] Blood clots can be fatal and can lead to loss of limbs and cognitive function. Furthermore, the longer a clot remains in place, the greater the risk to the patient. For example, clots can be dissolved using thrombolytic or anticoagulant drugs, but the use of such medications can cause significant complications for the patient, including bleeding and stroke. Blood clots can also be removed using devices, but at least some of the currently available clot removal devices require multiple passes to capture and / or remove the clot.

[0003] For example, in the case of acute ischemic stroke (AIS), time is essential for patient outcome because the longer the ischemic semi-infiltrated zone in the brain expands, the more fatal damage the ischemic semi-infiltrated zone can cause to the patient. Therefore, the sooner a physician can remove the thrombus from the neurovascular anatomy, the more likely the penumbra can be limited and the better the patient outcome. One of the limiting factors in this scenario is the number of passes it takes for a physician to completely remove the thrombus and fully recanalize the vessel. The more recanalizations there are, the longer the time the penumbra will expand. Devices and methods for safe and effective thrombus removal as quickly as possible can improve the prognosis of patients with occlusions. Summary of the Invention

[0004] Aspects of the current subject matter include various embodiments of an aspiration catheter and associated methods configured for removing a thrombus from a patient's blood vessel. In one aspect, the aspiration catheter may comprise an elongate body formed of a flexible material and having an inner lumen extending between a proximal body end and a distal body end. The inner lumen may be defined by an inner wall and may form a distal opening at the distal body portion. The aspiration catheter may further comprise a reinforcing member extending along a first length of the elongate body between the proximal reinforcing end and the distal reinforcing end. The distal reinforcing end may be disposed at a second length from the distal body end of the elongate body. The aspiration catheter may comprise a deformer extending along the second length of the elongate body. The deformer may be coupled to the second length such that the distal opening has a first opening diameter when the deformer forms a first configuration and has a second opening diameter when the deformer forms a second configuration, the second opening diameter being greater than the first opening diameter.

[0005] In some variations, the deformer may optionally include one or more of the following features in any feasible combination: The deformer may include an inflatable balloon. The inflatable balloon may extend helically along the second length of the elongate body. The inflatable balloon may be twisted along the second length of the elongate body. The distal opening may form a first suction area when the inflatable balloon is in the first configuration and a second suction area when the inflatable balloon is in the second configuration. The second suction area may be larger than the first suction area. The first and second suction areas may be defined by one or more of a diameter and a cross-sectional area of ​​the distal opening, respectively. The inflatable balloon may contract when in the first configuration and expand when in the second configuration. The deformer may include a shape memory member. The shape memory member may include a Nitinol material that transitions between the first and second configurations based on a temperature of the shape memory member. The shape memory member may include at least one Nitinol wire extending longitudinally along the second length. The shape memory member may comprise a stent retriever. The elongate body may be more flexible along the second length than along the first length. The reinforcing member may comprise one or more of a Teflon liner and a metal wire. The aspiration catheter may further comprise a plurality of LCP fibers extending along the second length of the elongate body. A first LCP fiber of the plurality of LCP fibers may be oriented longitudinally along the elongate body and a second LCP fiber of the plurality of LCP fibers may be oriented circumferentially along the elongate body.

[0006] In another aspect, the aspiration catheter may comprise an elongate body formed of a flexible material and having an inner lumen extending between a proximal body end and a distal body end. The inner lumen may be defined by an inner wall and form a distal opening at the distal body end. The aspiration catheter may further comprise a reinforcing member extending along a first length of the elongate body between the proximal reinforcing end and the distal reinforcing end. The distal reinforcing end may be disposed at a second length from the distal body end of the elongate body. The aspiration catheter may comprise a movable deformer slidably disposed along the inner lumen of the tubular elongate body. The movable deformer may be slidable along the first length of the elongate body. The movable deformer may form a collapsed configuration along the first length to allow the distal opening to form a first opening diameter. The movable deformer may be movable to the second length to form an expanded configuration to allow the distal opening to form a second opening diameter. The diameter of the second opening may be greater than the diameter of the first opening.

[0007] In some variations, the catheter may optionally include one or more of the following features in any feasible combination: The movable deformer may include a Nitinol material that transitions between a collapsed configuration and an expanded configuration based on a temperature of the movable deformer. The movable deformer may include a stent retriever. The movable deformer may include an expander. The aspiration catheter may further include a plurality of LCP fibers extending along a second length of the elongate body. A first LCP fiber of the plurality of LCP fibers may be oriented longitudinally along the elongate body and a second LCP fiber of the plurality of LCP fibers may be oriented circumferentially along the elongate body.

[0008] In another aspect, the aspiration catheter may comprise an elongate body formed of a flexible material and having an inner lumen extending between a proximal body end and a distal body end. The inner lumen may be defined by an inner wall and may define a distal opening at the distal body end. The distal opening may include a periphery extending along one or more planes, the periphery having a shape extending longitudinally relative to a longitudinal axis of the inner lumen. The aspiration catheter may further comprise a reinforcing member extending along the length of the elongate body.

[0009] In some variations, the catheter may optionally include one or more of the following features in any feasible combination: The distal opening may have an aspiration region defined by a periphery of the distal opening. The shape of the periphery may include an angular or triangular shape. The shape of the periphery may include a rounded or sinusoidal shape. The aspiration catheter may further include a plurality of LCP fibers extending along the elongate body. A first LCP fiber of the plurality of LCP fibers may be oriented longitudinally along the elongate body and a second LCP fiber of the plurality of LCP fibers may be oriented circumferentially along the elongate body.

[0010] In another aspect, the aspiration catheter may comprise an elongate body formed of a flexible material and having an inner lumen extending between a proximal body end and a distal body end. The inner lumen may be defined by an inner wall and form a distal opening at the distal body end. The aspiration catheter may further comprise a reinforcing member extending along a first length of the elongate body between the proximal reinforcing end and the distal reinforcing end. The distal reinforcing end may be disposed a second length from the distal body end of the elongate body. The aspiration catheter may comprise an occlusion gripping portion extending along an inner wall of the second length of the elongate body. The occlusion gripping portion may comprise an exposed coil configured to grip the thrombus to retain the thrombus at least partially within the inner lumen.

[0011] In some variations, the catheter may optionally include one or more of the following features in any feasible combination: The aspiration catheter may further include a plurality of LCP fibers extending along a second length of the elongate body. A first LCP fiber of the plurality of LCP fibers may be oriented longitudinally along the elongate body and a second LCP fiber of the plurality of LCP fibers may be oriented circumferentially along the elongate body. The elongate body may be more flexible along the second length than along the first length. The reinforcing member may include one or more of a Teflon liner and a metal wire.

[0012] In another interrelated aspect of the current subject matter, a method of removing a thrombus from a blood vessel of a patient includes inserting a distal portion of an aspiration catheter into the blood vessel. The aspiration catheter may comprise an elongate body formed of a flexible material and having an inner lumen extending between a proximal body end and a distal body end. The inner lumen may be defined by an inner wall and form a distal opening at the distal body end. The aspiration catheter may comprise a reinforcing member extending along a first length of the elongate body between a proximal reinforcing end and a distal reinforcing end. The distal reinforcing end may be disposed a second length from the distal body end of the elongate body. The aspiration catheter may further comprise a deformer extending along the second length of the elongate body. The deformer may be coupled to the second length such that the distal opening has a first opening diameter when the deformer forms a first configuration and the distal opening has a second opening diameter when the deformer forms a second configuration. The diameter of the second opening may be greater than the diameter of the first opening. The method may further include transitioning the deformer between a first configuration and a second configuration and applying a vacuum to the elongate body to aspirate at least a portion of the thrombus into a distal opening having a second opening diameter.

[0013] In some variations, the deformer may optionally include one or more of the following features in any feasible combination. The deformer may include an inflatable balloon. The inflatable balloon may extend helically along the second length of the elongate body. The inflatable balloon may be twisted along the second length of the elongate body. The distal opening may form a first suction area when the inflatable balloon is in a deflated configuration and a second suction area when the inflatable balloon is in an expanded configuration. The second suction area may be larger than the first suction area. The first and second suction areas may be defined by one or more of a diameter and a cross-sectional area of ​​the distal opening, respectively. The inflatable balloon may be deflated when in the first configuration and expanded when in the second configuration. The deformer may include a shape memory member. The shape memory member may include a Nitinol material that transitions between a first configuration and a second configuration based on a temperature of the shape memory member. The shape memory member may include at least one Nitinol wire extending longitudinally along the second length. The reinforcing member may comprise one or more of a Teflon liner and a metal wire. The suction catheter may comprise a plurality of LCP fibers extending along a second length of the elongate body. A first LCP fiber of the plurality of LCP fibers may be oriented longitudinally along the elongate body and a second LCP fiber of the plurality of LCP fibers may be oriented circumferentially along the elongate body.

[0014] In another aspect, a method of removing a thrombus from a blood vessel of a patient includes inserting a distal portion of an aspiration catheter into the blood vessel. The aspiration catheter may comprise an elongate body formed of a flexible material and having an inner lumen extending between a proximal body end and a distal body end. The inner lumen may be defined by an inner wall and form a distal opening at the distal body end. The aspiration catheter may further comprise a reinforcing member extending along a first length of the elongate body between the proximal reinforcing end and the distal reinforcing end. The distal reinforcing end may be disposed a second length from the distal body end of the elongate body. The aspiration catheter may comprise a movable deformer slidably disposed along the inner lumen of the tubular elongate body. The movable deformer may be slidable along the first length of the elongate body. The movable deformer may form a collapsed configuration along the first length to allow the distal opening to form a first opening diameter. The movable deformer may be movable to a second length to form an expanded configuration to allow the distal opening to form a second opening diameter. The second opening diameter may be greater than the first opening diameter. The method may further include transitioning the deformer between the first configuration and the second configuration and applying a vacuum to the elongate body to aspirate at least a portion of the thrombus into the distal opening having the second opening diameter.

[0015] In some variations, the catheter may optionally include one or more of the following features in any feasible combination: The movable deformer may include a Nitinol material that transitions between a collapsed configuration and an expanded configuration based on a temperature of the movable deformer. The movable deformer may include a stent retriever. The movable deformer may include an expander. The aspiration catheter may further include a plurality of LCP fibers extending along a second length of the elongate body. A first LCP fiber of the plurality of LCP fibers may be oriented longitudinally along the elongate body and a second LCP fiber of the plurality of LCP fibers may be oriented circumferentially along the elongate body.

[0016] In another aspect, a method of removing a thrombus from a patient's blood vessel includes inserting a distal portion of an aspiration catheter into the blood vessel. The aspiration catheter may include an elongate body formed of a flexible material and having an inner lumen extending between a proximal body end and a distal body end. The inner lumen may be defined by an inner wall and form a distal opening at the distal body end. The distal opening may include a periphery extending along one or more planes. The periphery may have a shape extending longitudinally relative to a longitudinal axis of the inner lumen. The aspiration catheter may include a reinforcing member extending along a length of the elongate body. The method may include applying a vacuum to the elongate body to aspirate at least a portion of the thrombus into the distal opening and form a suction seal between the periphery of the distal opening and the thrombus.

[0017] In some variations, one or more of the following features may optionally be included in any feasible combination: The distal opening may include an aspiration region defined by a periphery of the distal opening. The shape of the periphery may include an angular or triangular shape. The shape of the periphery may include a rounded or sinusoidal shape. The aspiration catheter may include a plurality of LCP fibers extending along the elongate body. A first LCP fiber of the plurality of LCP fibers may be oriented longitudinally along the elongate body and a second LCP fiber of the plurality of LCP fibers may be oriented circumferentially along the elongate body.

[0018] In another aspect, a method of removing a thrombus from a patient's blood vessel includes inserting a distal portion of an aspiration catheter into the blood vessel. The aspiration catheter may include an elongate body formed of a flexible material and having an inner lumen extending between a proximal body end and a distal body end. The inner lumen may be defined by an inner wall and form a distal opening at the distal body end. The aspiration catheter may include a reinforcing member extending along a first length of the elongate body between a proximal reinforcing end and a distal reinforcing end. The distal reinforcing end may be disposed a second length from the distal body end of the elongate body. The aspiration catheter may further include an occlusion gripping portion extending along an inner wall of the second length of the elongate body. The occlusion gripping portion may include an exposed coil configured to grip the thrombus to retain the thrombus at least partially within the inner lumen. The method may further include applying a vacuum to the elongate body to aspirate the thrombus to the distal opening and gripping the thrombus to retain the thrombus at least partially within the inner lumen.

[0019] In some variations, the catheter may optionally include one or more of the following features in any feasible combination: The aspiration catheter may further include a plurality of LCP fibers extending along a second length of the elongate body. A first LCP fiber of the plurality of LCP fibers may be oriented longitudinally along the elongate body and a second LCP fiber of the plurality of LCP fibers may be oriented circumferentially along the elongate body. The elongate body may be more flexible along the second length than along the first length. The reinforcing member may include one or more of a Teflon liner and a metal wire.

[0020] The details of one or more variations of the subject matter described herein are set forth in the accompanying drawings and the description below. Other features and advantages of the subject matter described herein will become apparent from the description and drawings, and from the claims. [Brief description of the drawings]

[0021] [Figure 1] FIG. 1 is a schematic diagram of normal antegrade cerebral or intracranial circulation with thrombotic occlusion of the left middle cerebral artery. [Diagram 2] FIG. 1 illustrates blood flow circulation after retrograde flow has been established using the retrograde flow system described herein. [Diagram 3] FIG. 1 illustrates the cerebral vasculature with an interventional device, such as a mechanical thrombectomy device, inserted through an exemplary arterial access device. [Figure 4] 13A-13C illustrate an alternative embodiment in which a secondary intervention device is advanced through an arterial access device into a collateral cerebral artery. [Diagram 5] FIG. 1 illustrates an exemplary embodiment of a vascular access and retrograde flow system used to establish retrograde flow during an intervention. [Figure 6] FIG. 1 illustrates another exemplary embodiment of a vascular access and retrograde flow system used to establish retrograde flow during an intervention. [Figure 7] FIG. 1 shows a close-up of the common carotid artery (CCA), internal carotid artery (ICA), and middle cerebral artery with arterial access and thrombectomy devices placed. [Figure 8A] FIG. 1 illustrates an embodiment of an arterial access device or system useful in the methods and systems of the present disclosure. [Figure 8B] FIG. 1 illustrates an embodiment of an arterial access device or system useful in the methods and systems of the present disclosure. [Figure 9A] FIG. 1 illustrates an embodiment of an arterial access device or system useful in the methods and systems of the present disclosure. [Figure 9B] FIG. 1 illustrates an embodiment of an arterial access device or system useful in the methods and systems of the present disclosure. [Figure 10A] 1 illustrates another embodiment of an arterial access device. [Figure 10B] 13A-13C show additional arterial access device configurations having a narrowed distal end. [Figure 11A] FIG. 13 is a diagram showing a sheath stopper tube. [Figure 11B] FIG. 13 is a diagram showing a sheath stopper tube. [Figure 11C]FIG. 13 shows another embodiment of the sheath stopper tube. [Figure 11D] FIG. 13 shows another embodiment of the sheath stopper tube. [Figure 11E] FIG. 13 shows another embodiment of the sheath stopper tube. [Figure 11F] FIG. 13 shows another embodiment of the sheath stopper tube. [Figure 11G] FIG. 13 shows another embodiment of the sheath stopper tube. [Figure 12A] 13A-13C show additional arterial access device configurations with expandable occlusion members. [Figure 12B] 13A-13C show additional arterial access device configurations including an expandable occlusion member and a reduced diameter distal end. [Figure 13] FIG. 1 illustrates a first embodiment of a venous return device useful in the methods and systems of the present disclosure. [Figure 14A] FIG. 1 illustrates an alternative venous return device useful in the methods and systems of the present disclosure. [Figure 14B] FIG. 1 illustrates an alternative venous return device useful in the methods and systems of the present disclosure. [Figure 14C] FIG. 1 illustrates an alternative venous return device useful in the methods and systems of the present disclosure. [Figure 15] FIG. 1 illustrates an example of a retrograde flow system including a schematic diagram of a flow control assembly. [Figure 16A] 1A-1D illustrate embodiments of variable flow resistance members useful in the methods and systems of the present disclosure. [Figure 16B] 1A-1D illustrate embodiments of variable flow resistance members useful in the methods and systems of the present disclosure. [Figure 17] 1 illustrates an arterial access device having a stepped configuration. [Figure 18A] FIG. 13 shows a cross-sectional detail of an exemplary Y-connector of an arterial access device. [Figure 18B] FIG. 13 shows a cross-sectional detail of an exemplary Y-connector of an arterial access device. [Figure 19A] 1 illustrates an exemplary arterial occlusion system and method. [Figure 19B] 1 illustrates an exemplary arterial occlusion system and method. [Figure 19C] 1 illustrates an exemplary arterial occlusion system and method. [Figure 19D] 1 illustrates an exemplary arterial occlusion system and method. [Figure 20A] FIG. 1 is a side cross-sectional view of one embodiment of an aspiration catheter comprising an elongate body having an internal lumen. [Figure 20B] FIG. 20B shows the distal end of the suction catheter of FIG. 20A. [Figure 21A] 1 is a side cross-sectional view of an embodiment of a distal end of an aspiration catheter comprising an inflatable balloon extending along an expandable distal portion of an elongate body and in a deflated configuration. FIG. [Figure 21B] FIG. 21B shows the distal end of the suction catheter of FIG. 21A. [Figure 21C] FIG. 21B is a side cross-sectional view of the aspiration catheter of FIG. 21A with the balloon in an inflated configuration. [Figure 21D] FIG. 21D shows the distal end of the suction catheter of FIG. 21C. [Figure 22A] 1 is a side cross-sectional view of an embodiment of a distal end of an aspiration catheter comprising an inflatable balloon in a deflated configuration, the balloon spiraling along an inflatable distal portion of an elongate body. FIG. [Figure 22B] FIG. 22B shows the distal end of the suction catheter of FIG. 22A. [Figure 22C] FIG. 22B is a side cross-sectional view of the aspiration catheter of FIG. 22A with the balloon in an inflated configuration. [Figure 22D] FIG. 22D shows the distal end of the aspiration catheter of FIG. 22C. [Figure 23A] FIG. 1 is a side cross-sectional view of an embodiment of the distal end of an aspiration catheter comprising an inflatable balloon in a deflated configuration, the balloon twisted along its length and spiraling along the inflatable distal portion of the elongate body. [Figure 23B] FIG. 23B shows the distal end of the suction catheter of FIG. 23A. [Figure 23C] FIG. 23B is a side cross-sectional view of the aspiration catheter of FIG. 23A with the balloon in an inflated configuration. [Figure 23D] FIG. 23D shows the distal end of the suction catheter of FIG. 23C. [Figure 24A] 1 is a side cross-sectional view of an embodiment of a distal end of an aspiration catheter including a deformer extending longitudinally along an expandable distal portion of an elongate body and in an expanded configuration. FIG. [Figure 24B] FIG. 24B shows the distal end of the suction catheter of FIG. 24A. [Figure 24C] 24B is a side cross-sectional view of the aspiration catheter of FIG. 24A, in which the shape memory deformer is in a collapsed configuration. [Figure 24D] FIG. 24D shows the distal end of the aspiration catheter of FIG. 24C. [Figure 25A] 1 is a side cross-sectional view of an embodiment of a distal end of an aspiration catheter including a shape memory deformer extending along an expandable distal portion of an elongate body and in an expanded configuration. FIG. [Figure 25B] FIG. 24B shows the distal end of the suction catheter of FIG. 24A. [Figure 25C] 25B is a side cross-sectional view of the aspiration catheter of FIG. 25A, in which the shape memory deformer is in a collapsed configuration. [Figure 25D] FIG. 25D shows the distal end of the aspiration catheter of FIG. 25C. [Figure 26A] 1 is a side cross-sectional view of an embodiment of a distal end of an aspiration catheter including a movable deformer disposed along an expandable distal portion of an elongate body and in an expanded configuration. FIG. [Figure 26B] FIG. 26B shows the distal end of the suction catheter of FIG. 26A. [Figure 26C] 26B is a side cross-sectional view of the aspiration catheter of FIG. 26A, with the movable deformer proximal to the expandable distal portion and in a folded configuration. [Figure 26D] FIG. 26D shows the distal end of the suction catheter of FIG. 26C. [Figure 27A]13 is a side cross-sectional view of another embodiment of a distal end of an aspiration catheter comprising a movable deformer disposed along an expandable distal portion of an elongate body and in an expanded configuration. FIG. [Figure 27B] FIG. 27B shows the distal end of the suction catheter of FIG. 27A. [Figure 27C] 27B is a side cross-sectional view of the aspiration catheter of FIG. 27A, with the movable deformer proximal to the expandable distal portion and in a collapsed configuration. [Figure 27D] FIG. 27D shows the distal end of the suction catheter of FIG. 27C. [Figure 28A] 1 is a side cross-sectional view of an embodiment of a distal end of an aspiration catheter having an angled periphery of a distal opening of an elongate body. FIG. [Figure 28B] FIG. 28B shows the distal end of the suction catheter of FIG. 28A. [Figure 29A] 1 is a side cross-sectional view of an embodiment of a distal end of an aspiration catheter having a sinusoidal perimeter of a distal opening of an elongate body. FIG. [Figure 29B] FIG. 29B shows the distal end of the suction catheter of FIG. 29A. [Figure 30A] 1 is a side cross-sectional view of an embodiment of a distal end of an aspiration catheter having an obstruction gripping portion. [Figure 30B] FIG. 30B shows the distal end of the suction catheter of FIG. 30A. [Figure 31A] FIG. 2 is a side cross-sectional view of the distal end of an embodiment of an aspiration catheter having liquid crystal polymer (LCP) fibers. [Figure 31B] FIG. 31B shows the distal end of the suction catheter of FIG. 31A. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] Methods and devices are disclosed that allow for safe, rapid and effective retrieval and removal of obstructing material from a patient's blood vessel. For example, various embodiments of an aspiration catheter are disclosed that can be used at least in combination with an arterial access device to access obstructing material (e.g., a thrombus) for removal. The disclosed systems and methods with an aspiration catheter are configured for use in a variety of blood vessels within a patient's body.

[0023] Further disclosed herein are methods and devices that allow safe, rapid and relatively short access to at least the cerebral arteries for the introduction of interventional devices to treat diseased or other conditions in the intracranial vasculature. The disclosed systems and methods are configured for use with at least the cerebral arteries, the neurovasculature, and the intracranial arteries, and these terms may be used interchangeably herein. Additionally, the disclosed methods and devices are configured to more reliably close access sites to the cerebral arteries. The disclosed methods and devices include a vascular access and retrograde flow system that can be safely and rapidly used for neurointerventional procedures.

[0024] The disclosed methods may be used following percutaneous or surgical access to the patient's vasculature. In an embodiment, the access location to the vasculature is in the neck region, such as the carotid artery, including the common carotid artery, the internal carotid artery, or the external carotid artery. The disclosed systems and methods use a neuroprotection system configured to generate reverse flow (also referred to as retrograde flow) through at least a portion of the carotid artery. The neuroprotection system may also be configured to stagnate flow in at least a portion of the carotid artery. To the extent that retrograde flow is generated, it may be generated in a passive or active manner, as described in more detail below. The disclosed systems and methods may utilize suction in the intracranial artery and / or the carotid artery.

[0025] The systems and methods of the present disclosure may be used to treat any of a variety of intracranial and neurovascular conditions, such as, for example, stroke, acute stroke, large vessel occlusion, intracranial atherosclerosis (ICAD), overlapping lesions, aneurysms, arteriovenous malformations (AVMs), arteriovenous fistulas, acute and chronic total carotid occlusion, with a variety of interventional devices, some examples of which are described herein. Additionally, a variety of occlusion devices and methods may be used in connection with occlusion of the access site to achieve hemostasis at the access site. The methods of the present disclosure may be used in connection with or without the placement of a stent in the artery.

[0026] In an exemplary method, an access location is provided or otherwise created at the level of the neck, such as in the region of the carotid artery, including the internal carotid artery, the external carotid artery, and / or the common carotid artery. The access location in one example is in the common carotid artery. An arterial access sheath (also referred to as an arterial access device), such as the arterial access device described herein, is then inserted into the artery through the access location. The sheath is inserted into the artery and threaded through the artery until a distal tip of the sheath is located at a desired location. In one embodiment, the distal tip of the sheath is located in the internal carotid artery. In another embodiment, the distal tip of the sheath is located in the external carotid artery or the common carotid artery. A retrograde flow condition is then optionally established, such as by clamping or occluding a portion of the carotid artery to achieve a pressure differential. A retrograde blood condition causes blood to flow from an artery (such as the carotid artery) into the sheath, where it can be diverted or diverted to a return location, such as an external container, or to the vascular system (veins or arteries). In another embodiment, an active flow condition may be achieved, such as by using a pump or syringe, as described in more detail below. A stasis flow condition may also be achieved, as previously described. A reverse flow condition acts as a neuroprotective system, as described in more detail below. An occlusion device may be applied to the access location to establish hemostasis, such as at the end of a therapeutic procedure, as discussed below. In one embodiment, the occlusion device is pre-placed at the access location prior to introducing any device (such as a guidewire, sheath, or interventional device) into the artery through the access location.

[0027] The arterial access device provides a passageway for inserting an interventional tool into the vasculature so that the interventional tool can be routed to a target treatment location, such as a blood vessel in the brain. In implantation, retrograde flow is used in combination with an interventional tool that includes an aspiration catheter to aspirate material (such as thrombus material) into the interventional device, such as a catheter, and / or into the arterial access sheath. In this regard, the interventional device and / or arterial access device may be inserted such that the distal tip of the device is located just proximal to the location to be aspirated or at any other location relative to the location to be aspirated. After the interventional tool has been used for treatment, the retrograde or stagnant flow condition is stopped to restore antegrade flow. During the procedure, the retrograde flow condition serves as neuroprotection, limiting or preventing material from flowing in an antegrade direction in the area of ​​intervention. As described below, an occlusion device may be placed at the access location during or after the procedure without removing the arterial access device from the access location or replacing the arterial access device with another device.

[0028] FIG. 1 is a schematic diagram showing normal antegrade cerebral circulation with an exemplary disease state (thrombotic occlusion 10) in, for example, the left middle cerebral artery LMCA. It should be understood that other disease states requiring intervention are within the scope of this disclosure. The left middle cerebral artery LMCA branches off from the left internal carotid artery LICA. The middle cerebral artery is a large artery with tree-like branches that bring blood to the entire lateral surface of each hemisphere of the brain. The thrombotic occlusion 10 occludes or restricts blood flow in the left middle cerebral artery. Thus, the blood supply to the brain is significantly interrupted by the presence of the thrombotic occlusion 10 in the left middle cerebral artery, resulting in an ischemic stroke condition.

[0029] In accordance with the use of the methods and systems described herein, a method of treatment includes obtaining vascular access to a cerebral artery and establishing retrograde flow in at least a portion of the cerebral circulation and / or the carotid artery to treat a thrombotic occlusion. In an exemplary procedure, an interventional device comprising a mechanical thrombus removal device (such as a stentriever) is inserted into the cerebral vasculature to remove or otherwise treat the thrombotic occlusion under retrograde flow conditions, as described below. FIG. 2 illustrates the blood flow circulation after retrograde flow has been established using the retrograde flow system described herein. The system comprises an arterial access device 110 that enters the left common carotid artery LCCA (or right common carotid artery) and provides access to the cerebral vasculature. The artery may be clamped. Alternatively, an expandable occlusion member 129 on the arterial access device 110 may be used to occlude an artery of the cerebral vasculature and establish retrograde flow, as described more fully below. For example, various arteries may be occluded, including the common carotid artery, the internal carotid artery, and / or the vertebral artery. Exemplary embodiments of the system and its components are described in detail below.

[0030] 3 illustrates the cerebral vasculature with a mechanical thrombus removal device 15 inserted through an arterial access device 110. The thrombus removal device 15 comprises an elongate catheter that can be advanced through the arterial access device 110 to the location of the thrombus occlusion 10. The thrombus removal device 15 has a distal region that comprises a thrombus engaging member 68 adapted to interact with and remove the thrombus occlusion 10, as will be described more fully below. The types of thrombus removal devices can vary. In another embodiment, the interventional device is an aspiration catheter that is positioned to interact with the target location through the arterial access device 110.

[0031] 4 illustrates another embodiment in which a secondary intervention device, such as a balloon catheter 25, is advanced through an arterial access device 110 into a collateral cerebral artery, such as the anterior cerebral artery ACA. The balloon catheter 25 includes a balloon 30 that is expandable within the collateral cerebral artery to occlude that artery. Occluding the collateral cerebral artery may facilitate aspiration and retrograde flow through the cerebral vasculature.

[0032] FIG. 5 illustrates an exemplary embodiment of a vascular access retrograde flow system 100 that can be used to establish retrograde flow during removal of a thrombus obstruction 10. The system 100 includes an arterial access device 110, a vascular return device, such as a venous return device 115, and a shunt 120 (which may be an extracorporeal shunt) that provides a pathway for retrograde flow from the arterial access device 110 to the venous return device 115. A flow control assembly 125 interacts with the shunt 120. The flow control assembly 125 is configured to regulate and / or monitor retrograde flow through the shunt 120, as described in more detail below. The flow control assembly 125 interacts with an external flow path through the shunt 120, an internal flow path, or both. FIG. 6 illustrates another view of the vascular access retrograde flow system 100 coupled to a patient.

[0033] In one embodiment, as described in more detail below, the arterial access device 110 is at least partially inserted into the common carotid artery CCA and the venous return device 115 is at least partially inserted into a venous return site such as the femoral vein or the internal jugular vein. The venous return device 115 may be inserted into the femoral vein FV through a percutaneous puncture in the groin. The arterial access device 110 and the venous return device 115 are connected to opposite ends of the shunt 120 with connectors.

[0034] As shown in FIG. 7, the distal end of the arterial access device 110 (with optional occlusion member 129, if present) may be placed in the ICA or other portions of the carotid artery. Also, in situations where access to the ICA is extremely tortuous, it may be preferable to place the occlusion member closer to the common carotid artery. As previously mentioned, the ICA may be clamped rather than occluded via an occlusion member. Thus, the artery may be occluded via a location external to the artery and / or via a location internal to the artery. When flow through the internal carotid artery is blocked (with an occlusion member 129 or a clamp such as an umbilical tape, vascular loop, etc.), the natural pressure gradient between the internal carotid artery and the venous system causes blood to flow retrogradely or in a reverse direction from the cerebral vasculature through the internal carotid artery and shunt 120 into the venous system. The flow control assembly 125 regulates, augments, assists, monitors, and / or otherwise regulates retrograde blood flow.

[0035] An interventional device (such as an aspiration catheter or other interventional device) is then deployed through the arterial access device 110 and via the internal carotid artery at a target location, such as the left middle cerebral artery. A distal region of the interventional device 15 is positioned within the middle cerebral artery, such as by interaction with a thrombus occlusion or other disease state. A proximal region of the interventional device protrudes from an access port in the arterial access device 110. This is explained in more detail with reference to FIG. 7, which shows an enlarged view of the common carotid artery CCA, the internal carotid artery ICA, and the middle cerebral artery MCA with the arterial access device 110 and the interventional device 15 deployed. The arterial access device 110 accesses the common carotid artery by a transcervical approach, such as by direct cutting into the common carotid artery CCA or percutaneous puncture of the CCA. The interventional device 15 gains access to the internal carotid artery ICA by insertion through an inner lumen of the arterial access device 110, such as by insertion into a proximal opening that provides access into the arterial access device 110.

[0036] As discussed, the arterial access device 110 provides access to the anterior and middle cerebral arteries through the common carotid artery CCA using a transcervical approach. Transcervical access provides a short length and a less tortuous path from the vascular access point to the target treatment site, thereby mitigating the time and difficulty of the procedure compared to, for example, a transfemoral approach. Furthermore, this access route reduces the risk of emboli from navigation of pathological, angulated or tortuous anatomy of the aortic arch or common carotid artery. In another embodiment, the arterial access device provides access to the basilar artery BA or posterior cerebral artery PCA via a cutdown into the vertebral artery or percutaneous puncture of the vertebral artery.

[0037] In one embodiment, the arterial access device 110 accesses the common carotid artery CCA via a direct surgical transcervical approach, in which the common carotid artery may be clamped or occluded with a tourniquet or other device.

[0038] In another embodiment, transcervical access to the common carotid artery is achieved percutaneously by an incision or puncture in the skin through which the arterial access device 110 is inserted. If an incision is used, the incision is, for example, about 0.5 cm in length. An occlusion member 129, such as an expandable balloon, may be used to occlude the internal carotid artery ICA or the common carotid artery CCA at a location proximal to the distal tip of the arterial access device 110. The occlusion member 129 may be disposed on the arterial access device 110 or on a separate device.

[0039] In another embodiment, the arterial access device 110 accesses the common carotid artery CCA via a transcervical approach, while the venous return device 115 accesses a venous return site other than the femoral vein, such as the internal jugular vein.

[0040] In another embodiment, the system provides retrograde flow from the carotid artery to an external container rather than to the venous return site. The arterial access device 110 is connected to the container via a shunt 120. The shunt 120 communicates with a flow control assembly 125. The retrograde flow of blood is collected in a container 130. If necessary, the blood is filtered and returned to the patient. The pressure in the container 130 may be set to zero pressure (atmospheric pressure) or lower so that blood flows in a retrograde direction from the cerebral vasculature to the container 130. Optionally, to achieve or enhance retrograde flow from the internal carotid artery, flow from the external carotid artery may be blocked by placing a balloon or other occlusion member in the external carotid artery, typically just above its bifurcation with the internal carotid artery.

[0041] In another embodiment, the backflow may be replaced or augmented by applying a suction source to a port (such as a stopcock) in communication with the flow shunt 120. Examples of suction sources include syringes, pumps, etc. The system may also include an active pump as part of the flow control assembly 125, where controls for pump flow rate and / or flow rate monitoring may be included in the assembly.

[0042] In yet another embodiment, the system may be used to deliver intra-arterial thrombolytic therapy, for example, through a side branch of the arterial access device 110. For example, thrombolytic therapy may be infused through the arterial access device 110 into the thrombotic occlusion 10 via the flush line 635. In another embodiment, the system may be used to deliver intra-arterial thrombolytic therapy through a microcatheter inserted into the arterial access device 110. The microcatheter is delivered to the thrombotic occlusion 10 to inject a thrombolytic drug. Thrombolytic therapy may be delivered in conjunction with or as an alternative to mechanical thrombectomy, such as with a thrombectomy device 15.

[0043] In another embodiment, the system 100 may include a means for perfusing the cerebral vasculature and ischemic brain tissue, for example, by a perfusion catheter delivered to a site distal to the thrombotic occlusion 10 via the arterial access device 110. The perfusion catheter is configured to deliver a perfusion solution to a desired location. The perfusion solution may be, for example, autologous arterial blood from the AV shunt 120 or from another artery, an oxygenated solution, or other neuroprotective agents. The perfusion solution may also be cryogenic to cool the brain tissue. This is another strategy that has been shown to minimize brain damage during ischemic periods. The perfusion catheter may also be used to deliver a bolus of intra-arterial thrombolytic agent following thrombolytic therapy. Typically, thrombolytic therapy takes 1-2 hours or more to clear the occlusion after the bolus is administered. Mechanical thrombectomy may also take 1-2 hours to adequately recanalize the occluded vessel. Distal perfusion of the ischemic area may minimize the level of brain damage during stroke treatment procedures.

[0044] Another embodiment of the system 100 includes a means for reperfusing cerebral blood vessels during acute stroke treatment procedures. Cerebral reperfusion, as described by Frazee et al., involves selectively cannulating and occluding the transverse sinus via the internal jugular vein and injecting blood into brain tissue via the superior sagittal sinus during treatment of ischemic stroke. The following articles describing intracerebral retroperfusion are incorporated herein by reference in their entirety: Frazee, JG and X. Luo (1999) "Retrograde Transvenous Perfusion," Crit Care Clin 15(4):777-88, vii and Frazee, JG and X. Luo et al. (1998) "Retrograde Transvenous Neuroperfusion: A Backdoor Treatment for Stroke," Stroke 29(9):1912-6. In addition to protecting the brain tissue, this perfusion creates a retrograde flow gradient in the cerebral arteries. The retrograde perfusion member used with the retrograde flow system 100 may not only provide oxygen to brain tissue, but may also assist in trapping embolic debris within the retrograde shunt during recanalization of the thrombotic occlusion 10.

[0045] Various interventional devices may be used. For example, the interventional device may be a thrombus removal device, such as a stentriever device. A stentriever is, for example, a self-expanding mesh tube attached to a wire that is guided through the arterial access device (and possibly a secondary catheter) into the vasculature so that the device can engage the thrombus or other disease state. The user guides the device through various blood vessels to a treatment location, such as a thrombus in the brain. The stentriever is then used to grab the thrombus, and when the user removes the catheter, the thrombus is extracted. In an exemplary embodiment, the interventional device is any device configured to be delivered to a treatment site and treat, such as by delivering a substance to the site, removing a substance from the site, and / or interacting with the treatment site in any way. For example, a stent, balloon, coil, adhesive, liquid, solid, or gel may be delivered to the treatment site. The thrombus removal device may comprise or be coupled to a microcatheter to aid in the delivery of the device into the distal vasculature.

[0046] It should be understood that the thrombus removal device 15 is not limited to a particular embodiment and various embodiments of thrombus removal or treatment devices can be used. For example, the device can be an expandable cage, basket, snare, or grasper used to capture and remove thrombus occlusions. The device can also be a thrombus disruption device used to break up thrombus for easier aspiration and removal. The thrombus disruption device can be, for example, a mechanical disruptor, a sonic or ultrasonic energy source, other energy source, or a hydraulic or vortex energy source to break up thrombus. The thrombus removal device can also include an aspiration means to remove thrombus occlusions.

[0047] Other means for providing flow through a thrombotic occlusion include, for example, recanalization means for delivering a balloon catheter to expand a passageway through the occlusion, or placing a stent through the thrombotic occlusion to create a lumen through the occlusion. The stent device may be a permanently implanted stent or a temporary stent to open the occluded passageway for a period of time until it is retrieved. The occlusion may be removed by the stent or by some other means of thrombus removal. Thrombectomy and recanalization devices may be used in combination with the injection of a thrombolytic agent. Some exemplary stent-related devices and methods are described in U.S. Pat. Nos. 5,964,773 and 5,456,667, which are incorporated herein by reference in their entireties.

[0048] An example of the use of a vascular access retrograde flow system with a thrombus removal device 15 will now be described. The arterial access device 110 is introduced into the common carotid artery CCA of a patient and positioned at least partially (such as at the distal end of the distal sheath) in the distal common carotid artery or internal carotid artery, as shown in FIG. 7. The thrombus removal device 15 is then advanced into the carotid artery through the arterial access device 110, with or without the microcatheter 60. Before further advancing the thrombus removal device 15, an occlusion member 129 on the arterial access device 110 may be expanded to reduce or stop antegrade flow through the vessel. In another embodiment, the retrograde flow is stopped by externally clamping the vessel. Stopping the flow in the vessel helps to prevent thromboemboli or portions thereof from migrating downstream with antegrade flow during positioning of the thrombus removal device 15 or retrieval of the thrombus. The thrombectomy device 15 is then advanced further into the vasculature, either via the microcatheter 60 or by itself within the arterial access device 110, to a location proximal, internal, or distal to the thrombus occlusion 10. During any portion of the procedure, retrograde flow is initiated within the vessel via a retrograde flow system (described below) and / or via active aspiration. In one embodiment, where the device 15 protrudes out of the distal opening of the arterial access device, there is a gap between the outer diameter of the device 15 and the inner diameter of the arterial access device 110. The gap is sized such that there is no seal between the outer diameter of the device 15 and the inner diameter of the arterial access device 110. This allows retrograde blood to flow into the distal opening of the arterial access device where the device 15 protrudes.

[0049] The thrombus removal device 15 is then positioned to contact the thrombus occlusion 10, and possibly even penetrate the thrombus occlusion.

[0050] The thrombus removal device 15 may be used in any suitable manner to engage the thrombus occlusion. For example, the microcatheter 60 or sheath 65 may be advanced through the thrombus occlusion and then retracted to expose the thrombus removal device 15. The thrombus removal device 15 is then retracted into the thrombus occlusion to engage the thrombus occlusion. The thrombus removal device 15 may be rotated as it is moved into the thrombus occlusion. The thrombus removal device 15 may also be used to engage the thrombus occlusion by simply retracting the microcatheter 60 or sheath 65 while expanded within the thrombus occlusion.

[0051] Another method to aid in the mechanical capture of thrombotic occlusions is to coat the devices and device components with a material that aids in the attachment of the thrombotic occlusions, particularly thrombi, to the device or components. This material may be, for example, fibrin or other suitable material.

[0052] It will be appreciated that other mechanical thrombectomy catheters may be used in a similar manner with such vascular access retrograde flow systems. Mechanical thrombectomy devices may include variations of the thrombectomy devices described above, such as expandable cages, wire or filament loops, graspers, brushes, etc. These thrombectomy devices may include suction lumens to reduce the risk of embolic debris causing ischemic complications. Thrombectomy devices may also include a thrombus disruption component, such as a fluid vortex, ultrasonic or laser energy component, balloon, etc., coupled with flushing and suction to remove the thrombus. Some exemplary devices and methods are described in the following U.S. patents and patent publications, all of which are incorporated by reference in their entirety: U.S. Patent No. 6,663,650, U.S. Patent No. 6,730,104, U.S. Patent No. 6,428,531, U.S. Patent No. 6,379,325, U.S. Patent No. 6,481,439, U.S. Patent No. 6,929,632, U.S. Patent No. 5,938,645, U.S. Patent No. 6,824,545, U.S. Patent No. 6,679,893, U.S. Patent No. 6,685,722, U.S. Patent No. 6,436,087, U.S. Patent No. 5,794,629, U.S. Patent Application Publication No. 2008 / 01772 45, U.S. Patent Application Publication No. 2009 / 0299393, U.S. Patent Application Publication No. 2004 / 0133232, U.S. Patent Application Publication No. 2020 / 183783, U.S. Patent Application Publication No. 2007 / 0198028, U.S. Patent Application Publication No. 2006 / 0058836, U.S. Patent Application Publication No. 2006 / 0058837, U.S. Patent Application Publication No. 2006 / 0058838, U.S. Patent Application Publication No. 2003 / 0212384, and U.S. Patent Application Publication No. 2002 / 0133111.

[0053] Exemplary Embodiments of a Retrograde Blood Flow System As discussed, system 100 includes an arterial access device 110, a return flow device 115, and a shunt 120 that provides a pathway for retrograde flow from the arterial access device 110 to the return flow device 115. The system also includes a flow control assembly 125 that interacts with the shunt 120 to regulate and / or monitor retrograde blood flow through the shunt 120. Exemplary embodiments of components of system 100 will now be described. The system may include or be combined with a neuro-interventional device.

[0054] (Arterial Access Device) Figures 8A and 8B show an exemplary embodiment of an arterial access device 110. The device includes a distal sheath 605 (also referred to as a sheath body 605), a proximal extension 610, and an adapter or Y-connector 620 that is fluidly connectable to a fluid path such as a shunt 120, as shown in Figure 8B. The arterial access device 110 may optionally include a sheath stopper 705 (described further below) and a guidewire 611.

[0055] The distal sheath 605 is the portion of the arterial access device 110 that is sized for insertion into the carotid artery and that is actually inserted into the artery during use. The distal sheath 605 is configured to be introduced through an incision or puncture in the wall of a common carotid artery, for example, an open surgical incision or a percutaneous puncture made using the Seldinger technique. The length of the distal sheath may vary. In a non-limiting example, the length is 18 cm or more. In another embodiment, the distal sheath may be in the range of 5 cm to 15 cm, for example, 10 cm to 12 cm. The inner diameter may be in the range of 7 Fr (1 Fr = 0.33 mm) to 10 Fr, for example, 8 Fr. The distal sheath 605 may be, in a non-limiting example, a 4 Fr sheath, a 6 Fr sheath, a 5 Fr sheath, or an 8 Fr sheath. In an embodiment, the distal sheath has an outer diameter of 4 Fr to 8 Fr, or up to 10.5 Fr, or up to 12 Fr.

[0056] If the sheath is introduced via a transcervical approach above the clavicle and below the carotid bifurcation, it is desirable for the sheath 605 to be highly flexible while retaining hoop strength to resist kinking and buckling. To this end, the distal sheath 605 may be circumferentially reinforced with braid, helical ribbon, helical wire, etc. In an alternative embodiment, the distal sheath is configured to be introduced through a percutaneous puncture into the femoral artery, such as in the groin, up the aortic arch into the target common carotid artery CCA.

[0057] FIG. 8A shows disassembled components of the arterial access device 110, including the arterial access sheath 605, the sheath dilator 645, the sheath stopper 705, and the sheath guidewire 611. FIG. 8B shows the arterial access device 110 assembled for insertion over the sheath guidewire 611 into the carotid artery. After the sheath is inserted into the artery and during the procedure, the sheath guidewire 611 and the sheath dilator 645 are removed. A flush line 635 is connected to the arterial access device 110 and may include a live valve 640 at its proximal end. The flush line 635 allows for the introduction of saline, contrast, etc. during the procedure. The flush line 635 may also allow for pressure monitoring during the procedure. In one embodiment, the dilator 645 has a distal region that protrudes 1.5 cm distally beyond the distal end of the sheath 605 when the dilator is positioned within the sheath.

[0058] The proximal extension 610 extends from the Y adapter 620 to the proximal end of the arterial access device 110 (such as at the location of the flush line 635, if present). The proximal extension 610 has an inner lumen in fluid communication with the inner lumen of the sheath 605. The embodiment of FIG. 8A includes a proximal hemostasis valve 625 at the proximal-most end of the arterial access device 110. In an embodiment described below with reference to FIG. 9A (or any embodiment described herein), the arterial access device 110 does not include a hemostasis valve, but may be removably connected to a hemostasis valve. Also, the hemostasis valve may be eliminated from the embodiment of FIGS. 8A and 8B.

[0059] 8A, a Y-adapter 620 (also referred to as a Y-connector) connects a proximal portion of the sheath 605 to the proximal extension 610. The Y-connector 620 may include a valve 670 that is operated to open or close a fluid connection to a connector or hub 680 that may removably connect to or at least partially form a fluid path, such as the shunt 120. That is, the hub is connected to and forms at least a portion of the retrograde shunt 120 (FIGS. 5 and 6).

[0060] A valve 670 (such as a live valve) is disposed immediately adjacent to the inner lumen of the Y adaptor 620 that communicates with the inner lumen of the sheath body 605. FIGS. 18A and 18B are cross-sectional detail views of an example of a Y adaptor 620 including a valve 670 and a hub 680. FIG. 18A shows the valve closed relative to the connector. This is the position the valve would be in during preparation of the arterial sheath. The valve is configured to prevent the possibility of air being trapped during preparation of the sheath. FIG. 18B shows the valve open relative to the connector. This position is used when the flow shunt 120 is connected to the hub 680 to allow blood flow from the arterial sheath to the shunt. This configuration eliminates the need to prime both a flush line and a flow path, instead allowing for a single flush line 635 and live valve 640 preparation. This single preparation is the same as preparation of a conventional introducer sheath that does not have a connection to a shunt line, making it more familiar and convenient for the user. Additionally, the lack of flow paths on the sheath allows for easier handling of the arterial sheath during preparation and insertion into the artery.

[0061] 8A, the sheath body 605 may include a second distal connector 690 separated from the Y adapter 620 by a segment of tubing 665. The purpose of this second distal connector and tubing 665 is to allow the valve 670 to be positioned further proximally from the distal tip of the sheath while still limiting the length of the insertable portion of the sheath 605, thereby reducing the user's exposure level to the radiation source when the flow shunt is connected to the arterial sheath during the procedure. In one embodiment, the distal connector 690 has a suture eyelet to aid in securing the sheath to the patient when positioned.

[0062] In an alternative embodiment of any of the embodiments of the arterial access device 110 described herein, the arterial access device does not include a hemostasis valve at its proximal end. Rather, the arterial access device has an open proximal end without a hemostasis valve (e.g., an unobstructed or completely unblocked proximal opening) to provide wider access than if a hemostasis valve were placed therein. In one embodiment, the proximal opening is sized to accept a catheter with an outer diameter of 0.071 inches, although this may be varied.

[0063] 9A illustrates another embodiment of an arterial access device 110 comprising a sheath body 605 having one or more depth markers 3205 sized and spaced along the sheath body 605 to provide an indication to a user regarding the depth of insertion of the sheath body 605 from the distal most end of the sheath body 605 to each depth marker 3205. In one embodiment, the depth markers are configured to provide an indication of a depth of at least 10 cm. In one embodiment, the sheath body 605 has a length of 18 cm, at least 18 cm, or less than 18 cm.

[0064] With further reference to FIG. 9A, the proximal extension 610 extends from the Y-adapter 620 to a proximal-most end at which a connector part 3210, such as a female Luer connector, is disposed. As previously described, a hemostasis valve is not disposed at the proximal-most end. The connector part 3210 may be configured to be removably attached to a corresponding connector on the proximal end of the arterial access dilator 645. As shown in FIG. 9B, the connector part 3210 may be configured to be removably attached to a rotating hemostasis valve (RHV) 3220 to achieve hemostasis. The RHV may comprise a Y-connector having a fluid line 3225 that communicates with the inner lumen of the arterial access device 110 when connected. The fluid line 3225 may function as a flush line, for example, used for flush fluid, and may comprise a member to control flow, such as a live valve. As previously described, the shunt 120 may be removably and fluidly connected to the arterial access device 110, as shown in FIG. 9B. The proximal end of the distal sheath 605 may have one or more suture eyelets disposed therein.

[0065] The distal tip of the distal sheath 605 may be made entirely or at least partially of a different material than the proximal portion of the sheath, such as a softer or more flexible material. The distal tip of the distal sheath 605 may define a distal-most edge that is disposed or aligned along a plane perpendicular to the longitudinal axis of the sheath. Alternatively, the distal tip of the distal sheath 605 may define a distal-most edge that is disposed or aligned along a plane that is angled (i.e., not normal) to the longitudinal axis of the sheath. In one embodiment, the sheath 605 is a 6 French or 8 French sheath. In one embodiment, the sheath 605 has an inner diameter of 0.071 inches, 0.058 inches, or 0.045 inches, and a length of 58 cm, although these specifications may be varied.

[0066] 9A , the proximal extension 610 (if present) is removably connected to the sheath 605 via at least one coupler or connector assembly 3215. The connector assembly 3215 may be located just proximal to the proximal end of the sheath and distal to the Y-arm 620 at the connection site. In this embodiment, an additional hemostatic valve may be provided at the connection site of the proximal extension 610 to the Y-arm connector 620 such that hemostasis is maintained when the proximal extension is not attached. The proximal extension 610 and the attached Y-connector 620 may then be removed together from the distal sheath 605 at the connector assembly 3215.

[0067] The connector assembly 3215 may comprise any of a wide variety of removably attached connector parts. The arterial access device 110 may comprise a first connector part 3217 (at the proximal end of the distal sheath 605) that is removably attached to a second connector part 3219 at the distal end of the Y-arm adapter 620 or at the distal end of the proximal extension 610. The first connector part 3217 and the second connector part 3219 may be rotary joints that are coupled to each other by a rotary mechanism such as a screw thread. In one embodiment, the connector parts are comprised of one or more Luer connectors. At least one of the connector parts may be a hemostasis valve or a hemostasis valve adapter. For example, the first connector part 3217 may be a hemostasis valve adapter configured to be removably attached to the second connector part 3219. The first connector part 3217 may also be removably attached to a hemostasis valve in one embodiment. The second connector part 3219 may then be removed from the first connector part 3217 to allow removal of the Y-arm adapter 620 and the proximal extension 610. A hemostasis valve assembly may then be attached to the first connector part 3217. In one embodiment, the first connector part 3217 and / or the second connector part 3219 include an automatic hemostasis member that automatically achieves hemostasis when the first connector part is removed from the second connector part. In an exemplary embodiment, the arterial access sheath has an overall length of less than 20 cm or less than 16 cm. In one embodiment, the length of the arterial access sheath has a working length of 11 cm and an outer diameter of 10.5 Fr.

[0068] In one embodiment, the arterial access device 110 has an overall length of 32 cm or greater. In an exemplary embodiment, the overall length of the distal sheath 605 is 16 cm, 20 cm, or other length less than 32 cm. The detachable proximal extension 610 (which also detaches the Y-arm connector or adapter 620 that connects to the shunt 120) allows the length of the arterial access device 110 to be shortened when the proximal extension 610 is removed from the distal sheath 605. In an exemplary method, the arterial access device 110 is used in accordance with a method of treatment with the arterial access device 110 fully assembled with both the proximal extension 610 and the distal sheath 605 attached. In this state, the arterial access device 110 may be used for the introduction of one or more interventional devices into the vasculature by inserting the interventional device through a proximal opening at the proximal end of the proximal extension.

[0069] At some point during the method, such as after treatment via the interventional device is completed, the Y-arm adapter 620 and the proximal extension 610 are removed from the sheath 605 (by decoupling the second connector part 2319 from the first connector part 3217), while the sheath 605 remains inserted into the artery without the Y-arm adapter 620 and the proximal extension 610. Thus, the sheath 605 provides a shorter access path into the artery compared to when the proximal extension 610 is attached to the sheath 605. The shorter access path may then be used to insert one or more devices for accessing and / or intervening within the artery without removing the entire arterial access device 110 and replacing it with a shorter access device. In one embodiment, the sheath 605 is used as an access path for inserting an occlusion delivery system into the artery, such as the occlusion delivery system described below in connection with FIGS. 19A and 19B. An occlusion device is then applied to achieve hemostasis at the access location. The sheath 605 is then removed. Alternatively, the proximal extension may be reconnected to the sheath 605 prior to removal. In one embodiment, the shorter access pathway allows for the insertion and use of one or more devices to access and / or intervene in the artery than if a longer access pathway with both the sheath and proximal extension were attached.

[0070] 10A-10B illustrate an alternative embodiment of the arterial access device 110. The sheath 605 may optionally have a stepped or other configuration with a reduced diameter distal region 630, as shown in FIG. 10B, which shows a close-up view of the distal region 630 of the sheath 605. The distal region 630 of the sheath may be sized for insertion into the carotid artery. The distal region 630 of the sheath typically has an inner diameter ranging from 0.085 inches to 0.115 inches, while the remaining proximal region of the sheath has a larger outer diameter and lumen diameter. The inner diameter typically ranges from 0.110 inches to 0.135 inches. The larger lumen diameter of the proximal region minimizes the overall flow resistance through the sheath. In one embodiment, the reduced diameter distal region 630 has a length of about 2 cm to 4 cm or 3 cm to 5 cm. In another embodiment, the narrowed distal region 630 has a length of about 10 cm to 15 cm. The relatively short length of the narrowed distal region 630 allows this section to be placed in the common carotid artery CCA via a transcervical approach while reducing the risk of the distal end of the sheath 605 contacting the bifurcation B. Additionally, the narrowed distal region 630 allows for a reduced size of the opening for introducing the sheath 605 into the artery while having a minimal impact on the level of flow resistance.

[0071] Referring again to FIG. 10A, the proximal extension 610 has an inner lumen that is fluidly continuous with the inner lumen of the sheath 605. The lumens of the proximal extension 610 and the sheath 605 are connected by a Y-connector 620 that connects the lumen of the flow path 615 to the sheath. In the assembled system, the flow path 615 connects to and forms a first leg of the retrograde shunt 120 (FIGS. 5 and 6). In any embodiment, the proximal extension 610 may have a length sufficient to position the proximal hemostatic valve 625 (or the proximal end of the arterial access device) away from the Y-connector 620 adjacent to the percutaneous or surgical insertion site. By positioning the hemostatic valve 625 away from the percutaneous insertion site, the physician can introduce an interventional system (such as a stent delivery system or other working catheter) within the proximal extension 610 and sheath 605 while remaining out of the fluoroscopic field when fluoroscopy is being performed.

[0072] To facilitate introduction of the sheath 605 into the common carotid artery, a dilator 645 may be provided having a tapered distal end 650. The dilator 645 may be introduced through the hemostasis valve 625 such that the tapered distal end 650 extends through the distal end of the sheath 605, as best seen in FIG. 11A. The dilator 645 may have a central lumen to accommodate a guidewire. Typically, a guidewire is first placed in the vessel and the dilator / sheath combination travels over the guidewire as the guidewire is introduced into the vessel.

[0073] The dilator may be of varying lengths. In one embodiment, the dilator has a length such that when the dilator is disposed within the inner lumen of the sheath 605, the tapered distal end 650, as well as the distal region of the dilator, protrudes outwardly from the distal end of the sheath 605. In an exemplary embodiment, the length of the dilator is 79 cm with a working length of 76 cm, although the length may be varied.

[0074] (Sheath stopper) Optionally, a tubular shaped sheath stopper 705 may be provided that is coaxially received on the outside of the sheath 605, as seen in FIG. 11A. The sheath stopper 705 is configured to act as a mechanical device to prevent the sheath from being inserted too far into the blood vessel. The sheath stopper 705 is sized and shaped to be placed on the sheath 605 so as to cover a portion of the sheath 605 and leave a distal portion of the sheath 605 exposed. The sheath stopper 705 may have a flared proximal end 710 that engages the adapter 620, and a distal end 715. Optionally, the distal end 715 may be beveled, as shown in FIG. 11B.

[0075] The sheath stop 705 can serve a variety of purposes. For example, the length of the sheath stop 705 limits the introduction of the sheath 605 to the exposed distal portion of the sheath 605 such that the insertion length of the sheath is limited to the exposed distal portion of the sheath. In one embodiment, the sheath stop limits the exposed distal portion to a range between 2 cm and 3 cm. In one embodiment, the sheath stop limits the exposed distal portion to 2.5 cm. In other words, the sheath stop may limit the insertion of the sheath into the artery to a range between about 2 cm and 3 cm, or may limit it to 2.5 cm. In another example, the sheath stop 705 may engage a puncture occlusion device (if present) pre-placed in the carotid artery wall to allow the sheath 605 to be withdrawn without dislodging the occlusion device.

[0076] The sheath stopper 705 may be made of a transparent material so that the sheath body can be clearly seen underneath the sheath stopper 705. The sheath stopper 705 may also be made of a flexible material or may have joints or sections that provide increased flexibility so that the sheath can be bent as needed at the appropriate location once inserted into the artery. The sheath stopper may be plastically bendable so that it can be bent into a desired shape so that it retains that shape when released by the user. The distal portion of the sheath stopper may be made of a harder material and the proximal portion may be made of a softer material. In one embodiment, the harder material is 85A durometer and the softer section is 50A durometer. In one embodiment, the harder distal portion is 1-4 cm of the sheath stopper 705. The sheath stopper 705 may be detachable from the sheath if the user desires a greater sheath insertion length. This allows a user to remove the sheath stopper 705, cut it to a shorter length, and reassemble it onto the sheath so that the length of the insertable sheath protrudes from the sheath stopper 705.

[0077] FIG. 11C illustrates another embodiment of a sheath stopper 705 disposed adjacent to a sheath 605 with a dilator 645 disposed therein. The sheath stopper 705 of FIG. 11C may be deformed from a first shape, such as a straight shape, to a second shape different from the first shape. The sheath stopper retains the second shape until a sufficient external force acts on the sheath stopper to change its shape. The second shape may be, for example, non-linear, curved, otherwise contoured, or irregular. For example, FIG. 11C illustrates a sheath stopper 705 having multiple bends as well as straight sections. It should be understood that FIG. 11C illustrates only one example, and the sheath stopper 705 may be formed to have any amount of bends along its longitudinal axis. FIG. 11D illustrates the sheath stopper 705 disposed on the sheath 605. The sheath stop 705 has a greater rigidity than the sheath 605 such that the sheath 605 assumes a shape or contour that matches the contour of the sheath stop 705 .

[0078] The sheath stop 705 may be shaped according to the angle of insertion of the sheath into the artery and the depth of the artery or the size of the patient. This feature reduces the force that the tip of the sheath exerts on the vessel wall, especially when the sheath is inserted into the vessel at a steep angle. The sheath stop may be bent or deformed into a shape that helps orient the sheath coaxially with the artery being entered, even when the angle of entry into the arteriotomy is relatively steep. The sheath stop may be shaped by the operator prior to inserting the sheath into the patient. Alternatively, the sheath stop may be shaped and / or reshaped in situ after the sheath is inserted into the artery. FIGS. 11E and 11F show an example of the use of a malleable sheath stop 705. FIG. 11E shows the sheath stop 705 positioned in the sheath 605 in a straight configuration. The sheath 605 assumes the straight shape of the sheath stop 705 and enters the artery A at a relatively steep angle such that the distal tip of the sheath 605 is tangent or facing the wall of the artery. In FIG. 11F, the user bends the sheath stop 705 to adjust the angle of entry of the sheath 605 so that the longitudinal axis of the sheath 605 is more aligned with the axis of the artery A. In this manner, the sheath stop 705 is formed by the user into a shape that assists in orienting the sheath 605 away from the opposing wall of the artery A and more coaxially with the axis of the artery A relative to the shape of FIG. 11E.

[0079] In one embodiment, the sheath stop 705 is made of a malleable material or has an integral malleable part disposed on or within the sheath stop. In another embodiment, the sheath stop is configured to articulate using an actuator such as a concentric tube, pull wire, or the like. The walls of the sheath stop may be reinforced with ductile wires or ribbons to help the sheath stop retain its shape against external forces such as when it encounters a bend in the artery or ostium. Alternatively, the sheath stop may be constructed of a homogenous malleable tubular material including metals and polymers. The sheath stop body may also be constructed at least in part of a reinforced braid or coil capable of retaining its shape after deformation.

[0080] Another sheath stop embodiment is configured to easily adjust the position of the sheath stopper (relative to the sheath) even after the sheath is placed in the container. One sheath stopper embodiment comprises a tube with slits along most or all of its length so that the sheath stopper can be peeled away from the sheath body, moved forward or backward as needed, and then repositioned along the length of the sheath body. The tube may have a tab or feature at the proximal end so that it can be grasped and more easily peeled away.

[0081] In another embodiment, the sheath stop is a very short tube (such as a band) or ring that resides in the distal section of the sheath body. The sheath stop may have features that allow it to be easily grasped, for example with forceps, and pulled back to a new position or forward as needed to set the sheath insertion length appropriate for the procedure. The sheath stop may be secured to the sheath body either by friction from the tubing or by a clamp that can be opened and closed against the sheath body. The clamp may be a spring-loaded clamp that is normally clamped to the sheath body. To move the sheath stop, the user may open the clamp with their fingers or an instrument, adjust the clamp position, and then release the clamp. The clamp is designed to not interfere with the sheath body.

[0082] In another embodiment, the sheath stop has a feature that allows for suturing the sheath stop and sheath to the patient's tissue to improve fixation of the sheath and reduce the risk of the sheath becoming dislodged. This feature may be a suture eyelet attached or molded into the tube of the sheath stop.

[0083] In another embodiment, as shown in FIG. 8A, the sheath stop 705 includes a distal flange 710 sized and shaped to distribute the force of the sheath stop over a larger area on the vessel wall, thereby reducing the risk of vessel injury or misinsertion of the sheath stop through the arteriotomy and into the vessel. The flange 710 may have a rounded or other atraumatic shape that is large enough to distribute the force of the sheath stop over a large area on the vessel wall. In an embodiment, the flange is inflatable or mechanically expandable. For example, the arterial sheath and sheath stop may be inserted into the surgical site through a small puncture in the skin and then expanded before inserting the sheath into the artery.

[0084] The sheath stop may have one or more notches or indentations 720 along its length patterned in a zigzag configuration to increase the bendability of the sheath stop while maintaining axial strength to allow for forward force of the sheath stop against the arterial wall. The indentations may also be used to facilitate fixation of the sheath to the patient with sutures and to reduce sheath migration. The sheath stop may also include a connector member 730 at its proximal end that corresponds to a feature on the arterial sheath so that the sheath stop may be locked or unlocked from the arterial sheath. For example, the connector member is a hub with a generally L-shaped slot 740 that corresponds to a pin 750 on the hub to create a bayonet mount type connection. In this manner, the sheath stop may be securely attached to the hub reducing the likelihood of the sheath stop being inadvertently removed from the hub unless unlocked from the hub.

[0085] The distal sheath 605 may be configured to establish a curvilinear transition from a generally anterior-posterior approach on the common carotid artery to a generally on-axis luminal direction within the common carotid artery. Arterial access through the arterial wall of the common carotid artery, either from a straight surgical cutdown or percutaneous access, may generally require a larger access angle than other sites of arterial access. This is due to the fact that the common carotid artery insertion site is much closer to the treatment site (i.e., the carotid bifurcation) than other access points. A larger access angle may be required to increase the distance from the insertion site to the treatment site so that the sheath can be inserted at an appropriate distance without the distal tip of the sheath reaching the carotid bifurcation. For example, in femoral artery access, the sheath insertion angle is 15-20 degrees, while in transcarotid artery access, the sheath insertion angle is typically 30-45 degrees or even greater. Thus, the sheath must bend more without kinking and without exerting excessive force on the opposing arterial wall compared to an introducer sheath. Additionally, it is desirable for the sheath tip to not impinge or contact the arterial wall after insertion in a manner that would restrict flow into the sheath. The sheath insertion angle is defined as the angle between the luminal axis of the artery and the longitudinal axis of the sheath.

[0086] The sheath body 605 may be shaped in various ways to allow for the large bending required by the access angle. For example, the sheath and / or dilator may have a combined flexible bending stiffness that is less than that of a typical introducer sheath. In one embodiment, the sheath / dilator combination (i.e., a sheath with a dilator disposed inside the sheath) has a combined flexible bending stiffness of about 80 to 100 N-m 2 ×10 -6 Composite flexibility stiffness (E * I), where E is the elastic modulus and I is the area moment of inertia of the device. The sheath alone has a stiffness of about 30-40 N-m 2 ×10 -6 The dilator alone has a bending stiffness in the range of about 40 to 60 N-m 2 ×10-6 A typical sheath / dilator may have a bending stiffness in the range of 150-250 N-m 2 ×10 -6 The sheath may have a thickness of 0.002" to 0.003" and a width of 0.005" to 0.015" and an outer jacket hardness of between 40 and 55D. In one embodiment, the coil ribbon is 0.003" by 0.010" and the outer jacket hardness is 45D. In one embodiment, the sheath 605 may be preformed with a curve or angle at a set distance from the tip, typically 0.5 to 1 cm. The preformed curve or angle may provide a turn typically within the range of 5° to 90°, preferably 10° to 30°. For initial introduction, the sheath 605 may be straightened with an obturator or other straight instrument, such as a dilator 645, placed within its lumen. After the sheath 605 has been introduced at least partially through a percutaneous or other arterial wall penetration, the occluder may be withdrawn to allow the sheath 605 to recapture its preformed configuration within the arterial lumen. The sheath may be heat set in the angled or curved shape during manufacture to retain the curved or angled shape of the sheath body after being straightened during insertion. A reinforcing structure may also be constructed from Nitinol and heat formed into the curved or angled shape during manufacture. Additional spring members may also be added to the sheath body. For example, a precisely shaped strip of spring steel or Nitinol may be added to the reinforcing layer of the sheath.

[0087] Other sheath configurations have a deflection mechanism that allows the sheath to be positioned and the catheter to be deflected in situ to a desired deployment angle. In yet other configurations, the catheter has a non-rigid configuration when positioned within the lumen of the common carotid artery. Once in place, pull wires or other stiffening mechanisms may be deployed to shape and stiffen the sheath into its desired configuration. One particular example of such a mechanism is commonly known as a "shape-lock" mechanism, as is well described in the medical patent literature.

[0088] Other sheath configurations include a curved dilator inserted into a straight but flexible sheath such that the dilator and sheath curve during insertion, the sheath being flexible enough to conform to tissue anatomy after removal of the dilator.

[0089] Another sheath embodiment is a sheath having one or more flexible distal sections such that once inserted and in an angled configuration, the sheath can bend at large angles without kinking and without exerting undue force on the opposing arterial wall. In one embodiment, there is a distal-most section of the sheath body 605 that is more flexible than the remainder of the sheath body. For example, the bending stiffness of the distal-most section is 2 to 10 times less than the bending stiffness of the remainder of the sheath body 605. In one embodiment, the distal-most section has a bending stiffness of 30 to 300 N-mm 2 and the remainder of the sheath body 605 has a bending stiffness in the range of 500 to 1500 N-mm 2For a sheath configured for a CCA access site, the flexible most distal section constitutes a significant portion of the sheath body that may be expressed as a ratio. In one embodiment, the ratio of the length of the flexible most distal section to the total length of the sheath body is at least one tenth and at most one half of the total length of the sheath body. This variation in flexibility may be achieved in a variety of ways. For example, the outer jacket may vary in hardness and / or material in various sections. Also, the reinforcing structure or material may vary over the length of the sheath body. In one embodiment, the flexible most distal section is in the range of 1 cm to 3 cm. In one embodiment having one or more flexible sections, the less flexible section (relative to the distal most section) may be in the range of 1 cm to 2 cm from the distal most section. In one embodiment, the flexible distal section is in the range of about 30 to 50 N-mm 2 ×10 -6 The less flexible section has a bending stiffness in the range of about 50-100 N-mm 2 ×10 -6In another embodiment, the more flexible section is located between 0.5-1.5 cm for a length of 1-2 cm, forming an articulation section where the sheath enters the artery at an angle but the distal section of the sheath is more easily aligned with the vessel axis. These configurations with variable flexibility sections may be manufactured in several ways. For example, the reinforced less flexible section may vary to have a stiffer reinforcement in the proximal section and a more flexible reinforcement in the distal or articulation section. In one embodiment, the sheath's outermost coating has a hardness of 45D-70D in the proximal section and a hardness of 80A-25D in the outermost distal section. In one embodiment, the flexibility of the sheath varies continuously along the length of the sheath body. FIG. 11G shows such a sheath inserted into an artery. The flexible distal section allows the sheath body to bend and the distal tip to generally conform to the vessel lumen. In one embodiment, the distal section is made with a more flexible reinforcement structure by varying the pitch of the coil or braid or by incorporating hypodermic tubes with a different cut pattern, and the distal section has a different reinforcement structure than the proximal section.

[0090] In one embodiment, the tapered tip of the distal sheath is made of a harder material than the distal sheath body. The purpose of this is to facilitate sheath insertion by allowing a smooth taper on the sheath and to reduce distortion or ovalization changes at the sheath tip during and after insertion of the sheath into the vessel. In one example, the distal tapered tip member is made of a harder material, such as a 60-72D Shore material. In another example, the distal tip is made of another material, such as HDPE, stainless steel, or other suitable polymer or metal. In an additional embodiment, the distal tip is made of a radiopaque material, either as an additive to the polymeric material, such as tungsten or barium sulfate, or as an inherent property of the material (as is the case with most metallic materials).

[0091] In another embodiment, the dilator 645 may have variable stiffness. For example, the tapered distal end 650 of the dilator may be made of a more flexible material than the proximal portion of the dilator to minimize the risk of vascular injury when the sheath and dilator are inserted into the artery. In one embodiment, the flexible distal section may have a stiffness of approximately 45-55 N-m. 2 ×10 -6 The less flexible proximal section has a bending stiffness in the range of about 60 to 90 N-m 2 ×10 -6 The dilator may also have a tapered shape optimized for transcarotid access. For example, the length of the taper and the amount of dilator extending beyond the sheath is preferably shorter than a typical introducer sheath to limit the amount of tip of the sheath and dilator entering the artery. For example, the length of the taper may be 1-1.5 cm and may extend 1.5-2 cm from the end of the sheath body. In one embodiment, the dilator has a radiopaque marker at the distal tip so that the location of the tip is easily visible under fluoroscopy.

[0092] In another embodiment, the introducer guidewire is optimally configured for transcarotid access. Typically, when inserting the introducer sheath into a blood vessel, the introducer guidewire is inserted into the blood vessel first. This may be done by either the micropuncture technique or the modified Seldinger technique. Usually, in the direction of the sheath insertion, there is a long length of blood vessel into which the introducer guidewire may be inserted, for example, the femoral artery. In this case, the user may introduce 10 cm to 15 cm or more of the guidewire into the blood vessel before inserting the sheath. The guidewire is designed to have a flexible distal section so as not to injure the blood vessel when it is introduced into the artery. The flexible section of the introducer sheath guidewire is usually 5 to 6 cm long, and gradually transitions into a stiff section. Inserting the guidewire 10 to 15 cm means that the stiff part of the guidewire is located in the puncture area, allowing it to stably support the subsequent insertion of the sheath and dilator into the blood vessel. However, in the case of transcarotid sheath insertion into the common carotid artery, there is a limit to the amount of guidewire inserted into the carotid artery. In cases where there is carotid disease at the bifurcation or internal carotid artery, it is desirable to insert the wire into the external carotid artery (ECA) to minimize the risk of embolism, so the amount of guidewire insertion may be about 5-7 cm, or about 3-5 cm, stopping before reaching the bifurcation. Thus, the transcarotid sheath guidewire may have a flexible distal section of 3-4 cm and / or a shorter transition section to a stiffer section. Also, the transcarotid sheath guidewire has an atraumatic tip section, but a very distal and short transition section to a stiffer section. For example, the flexible tip section may be 1.5-2.5 cm, followed by a transition section of 3-5 cm in length, followed by a stiff proximal section that constitutes the remainder of the wire.

[0093] In another embodiment, the sheath dilator is configured to be inserted over a 0.018 inch guidewire for percutaneous access. Standard sheath insertion using a micropuncture kit requires first inserting a 0.018 inch guidewire through a 22 Ga needle, then exchanging the guidewire for a 0.035 inch or 0.038 inch guidewire using a micropuncture catheter, and finally inserting the sheath and dilator over the 0.035 inch or 0.038 inch guidewire. A 0.014 inch guidewire may also be used. Some sheaths are insertable over 0.018 inch guidewires, eliminating the need for wire exchange. These sheaths are usually labeled "transradial" because they are designed for insertion into the radial artery, and the dilator taper is usually long enough to allow a sufficient diameter from the 0.018 inch wire to the sheath body. Unfortunately, these existing sheaths are not suitable for transcarotid access due to the limited insertion length of the sheath and dilator. Another drawback is that a 0.018 inch guidewire may not have the necessary support to insert a sheath having a sharper angle into the carotid artery. In an embodiment disclosed herein, the transcarotid sheath system includes a sheath body, a sheath expander, and an inner tube that slidably fits within the sheath expander and has a tapered distal end capable of accommodating a 0.018 inch guidewire.

[0094] To use this embodiment of the sheath system, a 0.018 inch guidewire is first inserted into the vessel through the 22 Ga needle. The coaxially assembled sheath system is then inserted over the 0.018 inch wire. The inner tube is first advanced over the 0.018 inch wire. The wire essentially deforms the inner tube into the equivalent of a 0.035 inch or 0.038 inch guidewire in both outer diameter and mechanical support. The inner tube is secured to the 0.018 inch wire at the proximal end. The sheath and dilator are then inserted into the vessel over the 0.018 inch wire and inner tube. This configuration allows for the same support of the guidewire as a standard introducer sheath, without the need for a long taper on the dilator as with current transradial sheaths, eliminating the wire exchange step. As noted above, this configuration of the sheath system may include a stop feature to prevent inadvertent advancement of the 0.018 inch guidewire and / or inner tube during sheath insertion. Once the sheath is inserted, the dilator, inner tube, and 0.018 inch guidewire are removed.

[0095] FIG. 12A illustrates another embodiment of the arterial access device 110. This embodiment is substantially the same as the embodiment shown in FIG. 8A, except that the distal sheath 605 includes an occlusion member 129 for occluding flow through, for example, the common carotid artery. Any of the arterial access device embodiments may include an occlusion member. If the occlusion member 129 is an expandable structure such as a balloon, the sheath 605 may include an inflation lumen in communication with the occlusion member 129. The occlusion member 129 may be an inflatable balloon, but may also be an inflatable cuff, a cone-shaped or other circumferential member that flares outward to engage the inner wall of the common or internal carotid artery to block flow beyond it, a membrane-coated braid, a slotted tube that expands radially when compressed axially, or a similar structure that can be deployed by mechanical means, or the like. In the case of balloon occlusion, the balloon may be compliant, non-compliant, elastic, reinforced, or have a variety of other properties. In one embodiment, the balloon is an elastic balloon that is closely received over the outside of the distal end of the sheath prior to inflation. Upon expansion, the compliant balloon can expand to conform to the inner wall of the common carotid artery. In one embodiment, the compliant balloon can expand to a diameter at least twice that of the undeployed configuration, and frequently can be deployed to a diameter at least three times that of the undeployed configuration, and more preferably can be deployed to a diameter at least four times that of the undeployed configuration or greater.

[0096] As shown in FIG. 12B, the distal sheath 605 with the occlusion member 129 may have a stepped or other configuration with a reduced diameter distal region 630. The distal region 630 may be sized for insertion into the carotid artery where the remaining proximal region of the sheath 605 has a larger outer diameter and lumen diameter. The inner diameter typically ranges from 0.110 inches to 0.135 inches. The larger lumen diameter of the proximal region minimizes the overall flow resistance of the sheath. In one embodiment, the reduced diameter distal section 630 has a length of about 2 cm to 4 cm or 3 cm to 5 cm. In another embodiment, the reduced diameter distal section 630 has a length of about 10 cm to 15 cm. The relatively short length of the reduced diameter distal section 630 allows this section to be placed into the common carotid artery CCA via a transcervical approach with reduced risk of the distal end of the sheath 605 contacting bifurcation B. In another embodiment, shown in FIG. 28, the reduced diameter distal section 630 is tapered or stepped and has a length of approximately 10 cm to 15 cm such that the distal tip is positioned in the internal carotid artery ICA.

[0097] In situations with sharp sheath insertion angles and / or short lengths of sheath inserted into the artery, such as those found in transcarotid access procedures, the distal tip of the sheath is likely to be partially or completely positioned against the vessel wall, thereby restricting flow into the sheath. In one embodiment, the sheath is configured to center the tip within the lumen of the vessel. One such embodiment includes a balloon, such as the occlusion member 129 described above. In another embodiment, the balloon may not be occlusive to flow, but may center the tip of the sheath away from the vessel wall, such as an inflatable bumper. In another embodiment, an expandable feature is located at the tip of the sheath and is mechanically expanded when the sheath is in place. Examples of mechanically expandable features include braided or helical structures, or longitudinal struts that radially expand when shortened.

[0098] In one embodiment, occlusion of the vessel proximate the distal tip of the sheath may be performed from outside the vessel, such as with a Rummel tourniquet or a vessel loop proximate the sheath insertion site. In an alternative embodiment, an occlusion device may be fitted externally to the vessel around the sheath tip, such as, for example, an elastic loop, an inflatable cuff, or a mechanical clamp that is tightened around the vessel and the distal sheath tip. In a flow reversal system, this method of occlusion of the vessel minimizes areas of static blood flow, thereby reducing the risk of thrombus formation, and also ensures that the sheath tip is axially aligned with the vessel and is not partially or completely blocked by the vessel wall.

[0099] In one embodiment, the distal portion of the sheath body may have side holes so that flow into the sheath is maintained even if the tip of the sheath is partially or completely blocked by the arterial wall.

[0100] (Venous return device) 13, the venous return device 115 comprises a distal sheath 910 and a channel 915 that connects to and forms the legs of the shunt 120 when the system is in use. The distal sheath 910 is adapted to be introduced through an incision or puncture into a venous return location, such as the jugular or femoral vein. The distal sheath 910 and channel 915 may be permanently attached or may be attached using a conventional luer fitting, as shown in FIG. 13. Optionally, as shown in FIG. 14A, the sheath 910 may be joined to the channel 915 by a Y-connector 1005. The Y-connector 1005 may comprise a hemostatic valve 1010 that allows for the insertion of a dilator 1015 to facilitate introduction of the venous return device into the internal jugular or other vein. Similar to the arterial access dilator 645, the venous dilator 1015 has a central guidewire lumen, so that the venous sheath and dilator combination may be placed over a guidewire. Optionally, the venous sheath 910 may include a flush line 1020 having a live valve 1025 at its proximal or distal end.

[0101] An alternative configuration is shown in Figures 14B and 14C. Figure 14B shows the components of a venous return device 115, including a venous return sheath 910, a sheath dilator 1015, and a sheath guidewire 611. Figure 14C shows the venous return device 115 as assembled for insertion over the sheath guidewire 611 into a central vein. Once the sheath is inserted into the vein, the dilator and guidewire are removed. The venous sheath may include a hemostatic valve 1010 and a flow channel 915. A live valve 1025 at the end of the flow channel allows for flushing of the venous sheath through the flow channel before use. This configuration allows the sheath to be prepared from a single point, similar to a conventional introducer sheath. Connection to the flow shunt 120 is made using a connector 1030 (such as a hemostatic valve) on the live valve 1025. The venous flow device 115 may include one or more eyelets that can be used to attach to sutures for securing the venous flow device 115 to the patient.

[0102] To reduce overall system flow resistance, the arterial access flow channel 615, the Y-connector 620 (FIG. 8A), the venous return flow channel 915, and the Y-connector 1005 (FIG. 13 or 14) may each have a relatively large flow lumen inner diameter, typically in the range of 0.100 inches to 0.200 inches, and a relatively short length, typically in the range of 10 cm to 20 cm. A low flow resistance in the system is desirable because it allows for maximizing fluid flow in the portion of the procedure where the risk of emboli is greatest. The low flow resistance of the system also allows for the use of variable flow resistance to control the flow rate in the system, as described in more detail below. The dimensions of the venous return sheath 910 may be approximately the same as those described for the arterial access sheath 605 above. In the venous return sheath, an extension for the hemostasis valve 1010 is not required.

[0103] (Retrograde shunt or flow channel) The shunt 120 may be formed of a single tube or multiple connected tubes that are in fluid communication between the arterial access catheter 110 and the venous return catheter 115 to provide a pathway for retrograde blood flow therebetween. As shown in Figures 5 and 6, the shunt 120 is connected at one end to the flow passage 615 of the arterial access device 110 and at an opposite end to the flow passage 915 of the venous return catheter 115.

[0104] In one embodiment, the shunt 120 may be formed of at least one tube in communication with the flow control assembly 125. The shunt 120 may be any structure that provides a fluid pathway for blood flow. The shunt 120 may have a single lumen or multiple lumens. The shunt 120 may be removably attached to the flow control assembly 125, the arterial access device 110, and / or the venous return device 115. Prior to use, a user may select a shunt 120 having a length most appropriate for use at the arterial access location and venous return site. In one embodiment, the shunt 120 may include one or more extension tubes that can be used to vary the length of the shunt 120. The extension tubes may be modularly attached to the shunt 120 to achieve a desired length. The modular aspect of the shunt 120 allows the user to lengthen the shunt 120 as needed depending on the venous return site. For example, in some patients, the internal jugular vein IJV is small and / or tortuous. The risk of complications at this site may be higher than some other sites due to its proximity to other tissue structures. Furthermore, hematomas in the neck may lead to airway obstruction and cerebrovascular complications. Therefore, for such patients, it may be desirable to place the venous return site at a site other than the internal jugular vein (IJV), such as the femoral vein. A femoral venous return site has a lower risk of serious complications, can be achieved percutaneously, and can provide alternative venous access to the central vein if the internal jugular vein (IJV) is not available. Furthermore, femoral venous return modifies the layout of the retrograde shunt so that the shunt control can be located closer to the "working area" of the intervention where the device is introduced and the contrast injection port is placed.

[0105] In one embodiment, the shunt 120 has an inner diameter of 3 / 16 inch (4.76 mm) and a length of 40-70 cm. As mentioned above, the length of the shunt can be adjusted and may vary from that described herein.

[0106] In one embodiment, the shunt may have a port that can be connected to a suction source, such as a syringe, suction pump, or the like.

[0107] In an additional embodiment, the shunt may include a member for connection to an active pump, such as, for example, a peristaltic pump, a diaphragm pump, an impeller pump, or a syringe pump.

[0108] (Flow Control Assembly - Regulating and Monitoring Retrograde Flow) The flow control assembly 125 interacts with the retrograde shunt 120 to regulate and / or monitor retrograde flow from the common carotid artery to a venous return site, such as the internal jugular vein, or to an external reservoir. In this regard, the flow control assembly 125 allows a user to achieve a higher maximum flow rate than existing systems and to selectively adjust, set, or otherwise regulate the retrograde flow rate. To regulate the retrograde flow rate, various mechanisms may be used, as described more fully below. The flow control assembly 125 allows a user to configure the retrograde blood flow in a manner suitable for various treatment regimens, as described below.

[0109] In general, the ability to control the continuous retrograde flow rate allows the physician to tailor the protocol to the individual patient and stage of the procedure. Retrograde blood flow rate is typically controlled over a range from a low rate to a high rate. The high rate may be at least two times higher than the low rate, typically at least three times higher than the low rate, and often at least five times higher than the low rate, or even higher. In one embodiment, the high rate is at least three times higher than the low rate. In another embodiment, the high rate is at least six times higher than the low rate. While it is generally desirable to have a high retrograde blood flow rate to maximize extraction of emboli from the carotid artery, patients vary in their ability to tolerate retrograde blood flow. Thus, by having a system and protocol that allows for easy adjustment of the retrograde blood flow rate, the treating physician may determine when the flow rate exceeds the patient's tolerance level and set the retrograde blood flow rate accordingly. For patients who cannot tolerate a continuous high retrograde flow rate, the physician may choose to turn on the high flow rate only for short, critical portions of the procedure where the risk of emboli is highest. Over short intervals, such as between 15 seconds and 1 minute, patient tolerance is usually not a factor.

[0110] In certain embodiments, the continuous retrograde blood flow rate may be controlled at a baseline flow rate ranging from 10 ml / min to 200 ml / min, typically 20 ml / min to 100 ml / min. These flow rates are acceptable for the majority of patients. During most of the procedure, the flow rate is maintained at the baseline flow rate, but when the risk of emboli release increases, the flow rate may be increased above baseline for short periods of time to improve the ability to capture such emboli. For example, the retrograde blood flow rate may be increased above baseline during introduction of a stent catheter, during deployment of a stent, before and after stent expansion, during removal of a common carotid artery occlusion, etc.

[0111] The flow control system may be cycled between a relatively low flow rate and a relatively high flow rate to "flush" the carotid artery in the region of the carotid bifurcation before re-establishing antegrade flow. Such a cycle may be established with a high flow rate that is about 2-6 times greater, typically about 3 times greater, than the low flow rate. Such cycles are typically in the range of 0.5 to 10 seconds, usually 2 to 5 seconds in length. The total duration of the cycle is in the range of 5 to 60 seconds, usually 10 to 30 seconds.

[0112] FIG. 15 illustrates an example of a system 100 having a schematic diagram of a flow control assembly 125 disposed along the shunt 120 such that retrograde blood flow passes through or communicates with at least a portion of the flow control assembly 125. The flow control assembly 125 may include various controllable mechanisms for regulating and / or monitoring retrograde flow. Such mechanisms may include various means for controlling retrograde flow, including one or more pumps 1110, valves 1115, syringes 1120, and / or variable resistance elements 1125. The flow control assembly 125 may be manually controlled by a user and / or automatically controlled via a controller 1130 to vary the flow through the shunt 120. For example, varying the flow resistance may control the amount of retrograde blood flow through the shunt 120. The controller 1130, described in more detail below, may be integrated into the flow control assembly 125 or may be a separate component in communication with components of the flow control assembly 125.

[0113] Additionally, the flow control assembly 125 may include one or more flow sensors 1135 and / or tissue data sensors 1140 (described in more detail below) to detect one or more aspects of retrograde flow. A filter 1145 may be positioned along the shunt 120 to remove emboli before blood is returned to the venous return site. If the filter 1145 is positioned upstream of the controller 1130, the filter 1145 may reduce the likelihood of emboli entering the controller 1130 and clogging the variable flow resistance element 1125. It should be understood that the various components of the flow control assembly 125 (including the pump 1110, valve 1115, syringe 1120, variable resistance element 1125, sensors 1135 / 1140, and filter 1145) may be positioned at various locations along the shunt 120 and at various upstream or downstream locations relative to one another. The components of the flow control assembly 125 are not limited to the locations shown in FIG. 15. Additionally, the flow control assembly 125 need not include all of the components, but may include various sub-combinations of the components. For example, a syringe may optionally be used within the flow control assembly 125 for flow regulating purposes, or may be used outside the assembly for purposes other than flow regulation, such as introducing a fluid, such as a radiopaque contrast agent, antegrade through the shunt 120 into an artery.

[0114] Both the variable resistance element 1125 and the pump 1110 may be coupled to the shunt 120 to control the retrograde flow rate. The variable resistance element 1125 controls the flow resistance while the pump 1110 provides active displacement of blood through the shunt 120. Thus, the pump may be actuated to drive retrograde flow without relying on the perfusion trunk and venous pressures of the ECA and ICA. The pump 1110 may be any type of pump including a peristaltic tube pump or a positive displacement pump. The pump 1110 may be activated and deactivated (manually or automatically via the controller 1130) to selectively effectuate the displacement of blood through the shunt 120 and control the flow rate through the shunt 120. Displacement of blood through the shunt 120 may also be achieved in other ways including the use of a suction syringe 1120. Alternatively, a suction source such as a vacutainer, a vacloc syringe, or wall suction may be used. The pump 1110 may be in communication with the controller 1130.

[0115] One or more flow control valves 1115 may be positioned along the path of the shunt. The valves may be manually actuated or automatically actuated (via controller 1130). The flow control valves 1115 may be, for example, one-way valves that limit antegrade flow through the shunt 120, check valves, or high pressure valves that occlude the shunt 120, for example, during high pressure contrast injection (intended to enter the arterial vasculature in an antegrade direction).

[0116] The controller 1130 communicates with components of the system 100, including the flow control assembly 125, to enable manual and / or automatic regulation and / or monitoring of retrograde flow through the components of the system 100 (e.g., including the shunt 120, the arterial access device 110, the venous return device 115, and the flow control assembly 125). For example, a user may actuate one or more actuators on the controller 1130 to manually control the components of the flow control assembly 125. Manual controls may include switches, dials, or similar components located directly on the controller 1130, or components located remotely from the controller 1130, such as a foot pedal or similar device. The controller 1130 may also automatically control the components of the system 100 without requiring input from a user. In one embodiment, a user may program software in the controller 1130 to enable such automatic control. The controller 1130 may control the actuation of mechanical portions of the flow control assembly 125. The controller 1130 may include circuitry or programming that interprets signals generated by the sensors 1135 / 1140 such that the controller 1130 can control operation of the flow control assembly 125 in response to such signals generated by the sensors.

[0117] The flow control assembly 125 may include an active pump actuator that interfaces with components within the shunt to allow active retrograde pumping of blood, such as a pump head for a roller pump, a rotary motor for an impeller type pump, etc. The controller 1130 will provide control of the pump speed.

[0118] The representation of the controller 1130 in FIG. 15 is merely exemplary. It should be understood that the controller 1130 may vary in appearance and structure. In FIG. 15, the controller 1130 is shown as being integrated into a single housing. This allows a user to control the flow control assembly 125 from one location. It should be understood that any components of the controller 1130 may be separated into separate housings. Additionally, FIG. 15 shows the controller 1130 and the flow control assembly 125 as separate housings. It should be understood that the controller 1130 and the flow control regulator 125 may be integrated into a single housing or split into multiple housings or components.

[0119] (Flow Status Indicator) The controller 1130 may include one or more indicators that provide a visual and / or audio signal to the user regarding the status of retrograde flow. An audio indication is advantageous to remind the user of the flow status without the user having to visually check the flow controller 1130. The indicator may include a speaker 1150 and / or a light 1155, or any other means for communicating the status of retrograde flow to the user. The controller 1130 may communicate with one or more sensors of the system to control the activation of the indicator. Alternatively, the activation of the indicator may be directly tied to the user activating one of the flow control actuators 1165. The indicator need not be a speaker or a light. The indicator may simply be a button or switch that visually indicates the status of retrograde flow. For example, a button in a certain state (such as pressed or down) may visually indicate that retrograde flow is in a high state. Alternatively, a switch or dial pointing to a particular labeled flow state may visually indicate that retrograde flow is in the labeled state.

[0120] The indicator may provide a signal indicative of one or more conditions of retrograde flow. In one embodiment, the indicator identifies only two distinct conditions: a "high" flow condition and a "low" flow condition. In another embodiment, the indicator identifies more than two flow rates, including a "high" flow rate, a "medium" flow rate, and a "low" flow rate. The indicator may be configured to identify any amount of the distinct conditions of retrograde flow, or may identify a scale signal corresponding to a condition of retrograde flow. In this regard, the indicator may be a digital or analog meter 1160 that indicates a value of retrograde flow rate, such as ml / min or any other unit.

[0121] In one embodiment, the indicator is configured to indicate to the user whether the retrograde flow is in a "high" flow state or a "low" flow state. For example, the indicator may illuminate in a first manner (e.g., brightness level) and / or emit a first audio signal when the flow rate is high, and then change to a second illumination manner and / or emit a second audio signal when the flow rate is low. Alternatively, the indicator may illuminate and / or emit an audio signal only when the flow rate is high or only when the flow rate is low. Considering that some patients may not be able to tolerate high flow rates or may not be able to tolerate high flow rates for extended periods of time, it may be desirable for the indicator to provide a notification to the user when the flow rate is high. This may serve as a fail-safe feature.

[0122] In another embodiment, the indicator provides a signal (audio and / or visual) when the flow rate changes state, such as when the flow rate changes from high to low and / or vice versa. In another embodiment, the indicator provides a signal when there is no retrograde flow, such as when the shunt 120 is blocked or when one of the valves in the shunt 120 is closed.

[0123] (Flow Actuator) The controller 1130 may include one or more actuators that a user can press, toggle, manipulate, or otherwise actuate to adjust the retrograde flow rate and / or monitor the flow rate. For example, the controller 1130 may include a flow control actuator 1165 (one or more buttons, knobs, dials, switches, etc.) that a user can actuate to selectively change aspects of the retrograde flow. For example, in the illustrated embodiment, the flow control actuator 1165 is a knob that can be rotated to various discrete positions, each corresponding to the controller 1130 causing the system 100 to achieve a particular retrograde flow state. Those states include, for example, (a) off, (b) low flow, (c) high flow, and (d) suction. It should be understood that the aforementioned states are merely exemplary and that different states or combinations of states may be used. The controller 1130 achieves the various retrograde flow states by interacting with one or more components of the system, including sensors, valves, variable resistance elements, and / or pumps. It should also be understood that the controller 1130 may also include circuitry and software to regulate retrograde flow rate and / or monitor flow rate such that the user does not have to actively activate the controller 1130.

[0124] The off state corresponds to a state in which there is no retrograde blood flow through the shunt 120. When the user sets the flow control actuator 1165 to off, the controller 1130 stops retrograde flow, such as by tightening a valve or closing a live valve in the shunt 120. The low-flow and high-flow states correspond to low and high retrograde flow rates, respectively. When the user sets the flow control actuator 1165 to low or high flow, the controller 1130 interacts with components of the flow control regulator 125, including the pump 1110, the valve 1115, and / or the variable resistance element 1125, to increase or decrease the flow rate as appropriate. Finally, the aspiration state corresponds to opening the circuit to a suction source, such as a vacutainer or aspiration unit, when active retrograde flow is desired. The aspiration source may be coupled to any portion of the circuit, including the shunt 120 or the arterial access device 110.

[0125] The system may be used to vary the blood flow between various states including active, passive, suction, and off states. The active state corresponds to a system that uses a means to actively drive retrograde blood flow. Such active means include, for example, a pump, a syringe, a vacuum source, etc. The passive state corresponds to when retrograde blood flow is driven by the ECA and ICA perfusion trunk pressure and possibly venous pressure. The suction state corresponds to a system that uses a suction source, such as a vacutainer or suction unit, to drive retrograde blood flow. The off state corresponds to a system where retrograde blood flow is zero, such as the result of a live valve or valves being closed. The low and high flow rates may be either passive or active flow states. In one embodiment, the particular values ​​(e.g., ml / min) of either the low and / or high flow rates may be pre-set and / or pre-programmed into the controller such that the user does not actually set or input the values. Rather, the user simply selects "high flow" and / or "low flow" (e.g., by pressing an actuator such as a button on the controller 1130), and the controller 1130 interacts with one or more components of the flow control assembly 125 to cause the flow to achieve a predetermined high or low flow value. In another embodiment, the user sets or inputs values ​​for the low and / or high flow, for example, into the controller. In another embodiment, the low and / or high flow rates are not actually set. Rather, external data (such as data from the tissue data sensor 1140) is used as a criteria to affect the flow rate.

[0126] The flow control actuator 1165 may be multiple actuators, such as one actuator, such as a button or switch, to switch the state from low flow rate to high flow rate, and another actuator to close the flow loop to an off state, for example, during injection of contrast where the contrast is directed forward into the carotid artery. In one embodiment, the flow control actuator 1165 may include multiple actuators. For example, one actuator may be operated to switch the flow rate from low to high, another actuator may be operated to temporarily stop the flow, and a third actuator (such as a live valve) may be operated to aspirate using a syringe. In another example, one actuator may be operated to switch to a low flow rate and another actuator may be operated to switch to a high flow rate. Alternatively, the flow control actuator 1165 may include multiple actuators to switch the state from low flow rate to high flow rate, and additional actuators to fine-tune the flow rate within the high flow rate state and the low flow rate state. When switching between low and high flow rates, these additional actuators may be used to fine-tune the flow rate within these states. Thus, it should be appreciated that within each state (i.e., high flow and low flow states), various flow rates may be dialed in. A wide variety of actuators may be used to achieve control over the flow conditions.

[0127] The controller 1130 or individual components of the controller 1130 may be located in various locations relative to the patient and / or relative to other components of the system 100. For example, the flow control actuator 1165 may be located near a hemostasis valve where any interventional tools are introduced into the patient to facilitate access to the flow control actuator 1165 during introduction of the tool. The location may vary based on whether a transfemoral or transcervical approach is used, for example. The controller 1130 may have a wireless connection and / or an adjustable length wired connection to the rest of the system 100 to allow remote control of the system 100. The controller 1130 may have a wireless connection with the flow control regulator 125 and / or an adjustable length wired connection to allow remote control of the flow control regulator 125. The controller 1130 may also be integrated into the flow control regulator 125. Where the controller 1130 is mechanically connected to components of the flow control assembly 125, a tether having mechanical actuation capability may connect the controller 1130 to one or more of the components. In one embodiment, the controller 1130 is located a sufficient distance from the system 100 to allow for placement of the controller 1130 outside of the radiation field when fluoroscopy is used.

[0128] The controller 1130 and any of its components may interact with other components of the system (pumps, sensors, shunts, etc.) in various ways. For example, any of a variety of mechanical connections may be used to enable communication between the controller 1130 and the components of the system. The controller 1130 may also communicate electrically or magnetically with the components of the system. Electromechanical connections may also be used. The controller 1130 may include control software that enables the controller to perform functions that control the components of the system. The controller itself may be a mechanical, electrical, or electromechanical device. The controller may be mechanically, pneumatically, or hydraulically actuated, or may be electromechanically actuated (e.g., in the case of solenoid actuation of flow control states). The controller 1130 may include a computer, computer processor, and memory, as well as data storage capabilities.

[0129] (Sensor) As previously mentioned, the flow control assembly 125 may include or interact with one or more sensors in communication with the system 100 and / or the patient's tissue structures. Each of the sensors may be configured to respond to a physical stimulus (including, for example, heat, light, sound, pressure, magnetism, motion, etc.) and transmit a result signal for measurement or display or to operate the controller 1130. In one embodiment, the flow sensor 1135 interacts with the shunt 120 to sense an aspect of the flow through the shunt 120, such as blood flow rate or volumetric flow rate. The flow sensor 1135 may be directly coupled to a display that directly displays the volumetric flow rate or flow rate value. Alternatively, the flow sensor 1135 may provide data to the controller 1130 for displaying the volumetric flow rate or flow rate.

[0130] The type of flow sensor 1135 may be varied. The flow sensor 1135 may be a mechanical device such as a paddle wheel, a flapper valve, a rotating ball, or any mechanical component that responds to flow through the shunt 120. The movement of the mechanical device in response to flow through the shunt 120 may serve as a visual indication of the fluid flow and may calibrate a scale as a visual indication of the fluid flow rate. The mechanical device may be coupled to an electrical component. For example, a paddle wheel may be disposed within the shunt 120 such that the fluid flow rotates the paddle wheel. The greater the rate of fluid flow, the greater the rotational speed of the paddle wheel. The paddle wheel may be magnetically coupled to a Hall effect sensor to detect the rotational speed, which is indicative of the fluid flow rate through the shunt 120.

[0131] In one embodiment, the flow sensor 1135 is an ultrasonic or electromagnetic flow meter capable of measuring blood flow without contacting the blood through the wall of the shunt 120. The ultrasonic or electromagnetic flow meter may be configured such that it does not need to contact the inner lumen of the shunt 120. In one embodiment, the flow sensor 1135 at least partially comprises a Doppler flow meter, such as a transonic flow meter, that measures fluid flow through the shunt 120. It should be understood that any of a wide variety of sensor types may be used, including ultrasonic flow meters and transducers. Additionally, the system may comprise multiple sensors.

[0132] The system 100 is not limited to using a flow sensor 1135 disposed within the shunt 120 or a sensor that interacts with the venous return device 115 or the arterial access device 110. For example, the tissue data sensor 1140 may communicate with or interact with a patient's tissue structure, such as a patient's neural tissue structure. In this aspect, the tissue data sensor 1140 may sense a measurable tissue aspect that is directly or indirectly related to the rate of retrograde flow from the carotid artery. For example, the tissue data sensor 1140 may measure blood flow conditions in the brain (e.g., flow rate in the middle cerebral artery) and communicate such conditions to a display and / or controller 1130 for adjusting the retrograde flow rate based on predetermined criteria. In one embodiment, the tissue data sensor 1140 includes a transcranial Doppler ultrasound (TCD), which is an ultrasound test that uses reflected sound waves to evaluate blood flowing in the brain. The use of a TCD results in a TCD signal that is communicated to the controller 1130 for controlling the retrograde flow rate to achieve or maintain a desired TCD profile. The tissue data sensor 1140 may be based on any physiological measurement, including retrograde flow velocity, blood flow through the middle cerebral artery, TCD signals of embolic particles, or other neuromonitoring signals.

[0133] In one embodiment, the system 100 constitutes a closed-loop control system. In a closed-loop control system, one or more sensors (such as the flow sensor 1135 or tissue data sensor 1140) sense or monitor certain aspects of the system 100 or tissue (e.g., retrograde flow rate and / or nerve monitoring signals). The sensors provide relevant data to the controller 1130, which continuously adjusts aspects of the system as needed to maintain a desired retrograde flow rate. The sensors communicate feedback to the controller 1130 about how the system 100 is operating, which the controller 1130 interprets and activates components of the flow control regulator 125 to dynamically compensate for disturbances in the retrograde flow rate. For example, the controller 1130 may include software that causes the controller 1130 to send signals to components of the flow control assembly 125 to adjust the flow rate such that the flow rate remains constant despite different blood pressures from the patient. In this embodiment, the system 100 does not need to rely on the user to determine when, how long, and / or at what value to set the retrograde flow rate to either a high or low state. Rather, software within the controller 1130 may govern such factors. In a closed loop system, the controller 1130 may control components of the flow control assembly 125 to establish a level or state of retrograde flow (either an analog level or a discrete state such as high, low, baseline, intermediate, etc.) based on the retrograde flow rate sensed by the sensor 1135.

[0134] In one embodiment, the tissue data sensor 1140 (measuring a physiological measure of the patient) transmits a signal to the controller 1130, which adjusts the flow rate based on the signal. For example, the physiological measure may be based on flow velocity through the MCA, a TCD signal, or other cerebrovascular signal. In the case of a TCD signal, the TCD may be used to monitor changes in cerebral flow and detect microemboli. The controller 1130 may adjust the flow rate to maintain the TCD signal within a desired profile. For example, the TCD signal may indicate the presence of a microemboli (a "TCD hit"), and the controller 1130 may adjust the retrograde flow rate to maintain the TCD hit below a hit threshold.

[0135] In the case of MCA flow, the controller 1130 may set the retrograde flow rate to the "maximum" flow rate tolerated by the patient as assessed by perfusion to the brain. Thus, the controller 1130 may control the retrograde flow rate to optimize the level of protection for the patient without relying on user intervention. In another embodiment, the feedback is based on the state of the devices in the system 100 or the interventional tool being used. For example, a sensor may notify the controller 1130 when the system 100 is in a high-risk state (e.g., when an interventional catheter is positioned within the sheath 605). The controller 1130 then adjusts the flow rate to compensate for such a condition.

[0136] The controller 1130 may be used to selectively increase retrograde flow in various ways. For example, it has been observed that a larger retrograde flow rate results in a larger drop in blood flow to the brain. Most importantly, the ipsilateral MCA may not be adequately compensated with collateral flow from the Circle of Willis. Thus, a prolonged high retrograde flow rate may not provide sufficient blood flow to the patient's brain, leading to the patient's intolerance as indicated by neurological symptoms. Studies have shown that MCA blood flow velocity below 10 cm / sec is a threshold at which the patient is at risk of neurological blood insufficiency. There are other indicators to monitor adequate perfusion to the brain, such as EEG (electroencephalogram) signals. However, high flow rates may be tolerated, even up to a complete cessation of MCA flow for short periods of time, from about 15 seconds to 1 minute.

[0137] In this manner, the controller 1130 can optimize capture of embolic debris by automatically increasing the retrograde flow only during limited periods corresponding to periods of high risk of embolic development during the procedure. These high-risk periods include periods during which an interventional device (such as the thrombus removal device 15) crosses the thrombus occlusion 10. During periods of low risk, the controller may return the retrograde flow rate to a lower baseline level. This lower level may correspond to low retrograde flow in the ICA or little antegrade flow in patients with a high perfusion pressure ratio of the ICA to the ECA.

[0138] In flow regulation systems where the flow state is manually set by the user, there is a risk that the user will not pay attention to the state of retrograde flow (high or low) and will inadvertently maintain the circuit at a high flow rate. This can lead to adverse patient reactions. In one embodiment, as a safety mechanism, the initial flow rate is a low flow rate. This serves as a fail-safe measure for patients who cannot tolerate high flow rates. In this regard, the controller 1130 may bias the system back to a low flow rate after a predetermined period of time at the high flow rate. Biasing to a low flow rate may be accomplished by electronics or software, or may be accomplished using mechanical components or a combination thereof. In one embodiment, the flow control actuator 1165 of the controller 1130 and / or the valve 1115 and / or the pump 1110 of the flow control regulator 125 are spring loaded toward a state that achieves a low flow rate. The controller 1130 is configured to allow the user to override the controller 1130 to manually return the system to a low flow rate state, if desired.

[0139] In another safety feature, the controller 1130 includes a timer 1170 (FIG. 15) that records the time for which the flow rate has been at the high flow rate. The controller 1130 may be programmed to automatically return the system 100 to the low flow rate after a predetermined period of time at the high flow rate (e.g., 15, 30, or 60 seconds or more). After the controller returns to the low flow rate, the user may initiate another predetermined period of high flow rate, if desired. Additionally, the user may override the controller 1130 to transition the system 100 to the desired low (or high) flow rate.

[0140] In an exemplary procedure, the retrograde flow level is initially set to a low flow rate, then switched to a high flow rate for a discrete period during a critical stage of the procedure, optimizing capture of embolic debris while avoiding patient tolerance issues. Alternatively, the flow rate is initially set to a high flow rate, and then the patient's tolerance to that level is checked before proceeding with the remainder of the procedure. If the patient shows signs of intolerance, the retrograde flow rate is reduced. The patient's tolerance may be determined automatically by the controller based on feedback from the tissue data sensor 1140, or by the user based on patient observation. Adjustments to the retrograde flow rate may be made automatically by the controller or manually by the user. The user may also monitor flow velocity through the middle cerebral artery (MCA), for example using a TCD, and set the maximum level of retrograde flow that maintains the MCA flow velocity above a threshold. The entire procedure may be performed without changing the flow rate state. If the MCA flow rate changes during the procedure or the patient develops neurological symptoms, adjustments may be made accordingly.

[0141] (Exemplary Mechanisms Regulating Reflux) The system 100 is configured to regulate retrograde flow in a variety of ways. Any combination of the pump 1110, valve 1115, syringe 1120, and / or variable resistance element 1125 may be controlled manually by a user or automatically by the controller 1130 to regulate the retrograde flow rate. This allows the system 100 to regulate the retrograde flow in a variety of ways, such as by controlling active flow components (e.g., pumps, syringes, etc.), reducing flow restriction, switching to a suction source (pre-set vac-lock syringe, vacutainer, suction system, etc.), or any combination thereof.

[0142] In situations where an external container or reservoir is used, retrograde flow may be increased in a variety of ways. The reservoir has a head height that is the height of the blood in the reservoir and the height of the reservoir relative to the patient. Retrograde flow into the reservoir may be adjusted by setting the height of the reservoir to increase or decrease the amount of pressure gradient from the CCA to the reservoir. In one embodiment, the reservoir is elevated to increase the reservoir pressure to a pressure greater than the venous pressure. Alternatively, the reservoir may be placed below the patient, such as lowered to floor level, to reduce the reservoir pressure to a pressure less than the venous pressure or atmospheric pressure.

[0143] Variable flow resistance within the shunt 120 may be provided in a wide variety of ways. In this regard, the flow resistance element 1125 may vary the size or shape of the shunt to change the flow conditions and thereby the flow rate. Alternatively, the flow resistance element 1125 may reroute blood flow through one or more alternative flow paths within the shunt to change the flow conditions. Several exemplary embodiments of the flow resistance element 1125 are now described.

[0144] In a non-limiting embodiment, the flow resistance through the shunt 120 may be altered by providing two or more alternative flow paths. As shown in Figures 16A and 16B, the flow through the shunt 120 passes not only through the main lumen 1700 but also through the secondary lumen 1705. The secondary lumen 1705 is longer and / or has a smaller diameter than the main lumen 1700. As a result, the secondary lumen 1705 has a higher flow resistance than the main lumen 1700. By passing blood through both of these lumens, the flow resistance is minimized. Blood can flow through both lumens 1700, 1705 due to the pressure loss in the main lumen 1700 across the inlet and outlet of the secondary lumen 1705. This has the advantage of reducing blood stagnation. As shown in FIG. 20B, by blocking flow through the main lumen 1700 of the shunt 120, flow can be diverted entirely to the secondary lumen 1705, thereby increasing flow resistance and decreasing blood flow rate. It should also be understood that additional flow lumens may be provided in parallel to allow for three, four, or more separate flow resistances. The shunt 120 includes a valve 1710 that controls flow to the main lumen 1700 and the secondary lumen 1705, which may be controlled by the controller 1130 or manually by the user. The embodiment of FIG. 16A and FIG. 16B is advantageous in that this embodiment does not require a small lumen size to achieve a desired retrograde flow rate, as with other embodiments of the variable flow resistance mechanism. This is advantageous in that a larger lumen size is less likely to clog and cause a blood clot in the blood flow line than a smaller lumen size.

[0145] (Occluded) Prior to withdrawal of the sheath 605 at the end of the procedure, any type of occlusion member, including a self-occluding member, may be placed around the penetration in the wall of the common carotid artery. The occlusion member may be placed at or near the beginning of the procedure, but optionally, the occlusion member may be placed as the sheath is withdrawn and released from the distal end of the sheath onto the wall of the artery (such as the common carotid artery) where the penetration occurs. The use of a self-occluding member is advantageous because it substantially affects a rapid occlusion of the penetration in the common carotid artery as the sheath is being withdrawn. Such rapid occlusion can reduce or eliminate unintended blood loss at the end of the procedure or during accidental dislodging of the sheath. Furthermore, such a self-occluding member can reduce the risk of arterial wall dissection during access. Furthermore, the self-occluding member may be configured to exert a frictional or other retaining force against the sheath during the procedure. Such a retaining force can be advantageous and reduce the likelihood of accidental dislodging of the sheath during the procedure. The self-occluding element eliminates the need for vascular surgical occlusion of the artery with sutures after removal of the sheath, reduces the need for a large surgical field, and greatly reduces the surgical skill required for the procedure.

[0146] The disclosed systems and methods may use a wide variety of occlusion members, such as mechanical members that include an anchor portion and an occlusion portion, such as a self-occluding portion. The anchor portions may include hooks, pins, staples, clips, teeth, sutures, etc., that engage the exterior surface of the common carotid artery around the penetration to secure the self-occluding member when the penetration is fully open. The self-occluding member may also include a spring-like or other self-occluding portion that will close the anchor portion upon removal of the sheath to draw the tissue of the arterial wall together to provide occlusion. Typically, this occlusion is sufficient such that no further measures need to be taken to occlude or seal the penetration. However, optionally, it may be desirable to provide a secondary seal of the self-occluding member after the sheath is withdrawn. For example, the self-occluding member and / or tissue tract in the region of the member may be treated with a hemostatic material, such as a bioabsorbable polymer, collagen plug, adhesive, sealant, clotting factor, or other clotting promoter. The tissue or self-occluding member may also be sealed using other sealing protocols, such as electrocautery, suturing, clipping, stapling, etc. In the alternative, the self-occluding member may be a self-sealing membrane or gasket material that is attached to the outer wall of the blood vessel with clips, adhesives, bands, or other means. The self-sealing membrane may have an internal opening, such as a slit or cross-cut, that is normally closed to blood pressure. These self-occluding members may be designed to be placed in an open surgical procedure or to be deployed percutaneously. The occlusion example described below may be modified to deliver an expandable collagen plug that spreads or expands when placed in the artery to fill the arterial opening and achieve hemostasis.

[0147] In one embodiment, the occlusion member is a suture-based vaso-occlusion device that can provide dilation of the arteriotomy puncture, thereby eliminating the need for prior dilation of the arteriotomy puncture with a separate device or procedural sheath dilator. The suture-based vaso-occlusion device may have one or more sutures placed across the vascular access site such that when the suture ends are tied after removal of the sheath, the sutures provide hemostasis at the access site. The sutures may be applied prior to insertion of a procedural sheath through the arteriotomy or after removal of the sheath from the arteriotomy. The device may maintain temporary hemostasis at the arteriotomy after placement of the sutures, before and during placement of the procedural sheath, and after withdrawal of the procedural sheath, before tying the sutures. Some exemplary suture-based vaso-occlusion devices are described in U.S. Patent Nos. 7,001,400 and 7,004,952, which are incorporated herein by reference in their entireties.

[0148] In one embodiment described with reference to FIGS. 19A-19D, a system and method are shown for hemostasis at a puncture site in an artery, such as the carotid artery, using a hemostatic delivery device 1902, which is an elongated body configured to deploy a device configured to achieve hemostasis. A user places an introducer sheath 1905 (which may be a separate sheath or may be the arterial access device 110) at an access location in the artery, such as the neck. The introducer sheath may be deployed percutaneously into the artery. The access location may extend through the skin 1910 and the outer wall of the carotid artery CA. A distal end of the sheath 1905 is placed in a lumen 1915 of the carotid artery CA. The user then inserts the hemostatic delivery device 1902 through the introducer sheath 1905 having a hemostatic member coupled, such as to a distal end or region of the hemostatic delivery device, as shown in FIG. 19B. The hemostatic member may be, for example, an inflatable hemostatic member 1920. The hemostatic delivery device 1902 is deployed through the sheath 1905 such that the hemostatic member 1920 is disposed outside the distal tip of the sheath 1905 and within the lumen 1915 .

[0149] 19C and 19D, the hemostatic member 1920 is deployed. After the hemostatic member 1920 is deployed outward, the hemostatic device 1902 may be pulled proximally to engage the hemostatic member 1920 with the wall of the artery. The introducer sheath 1905 may then be removed leaving the expandable hemostatic member 1920 seated in position 1925 forming an entrance into the carotid artery CA, and hemostasis may be achieved. An external tensioning member, such as a clip 1920, may be placed on the skin surface to maintain tension to hold the expandable hemostatic member 1920 in place. Exemplary occlusion systems are described in U.S. Pat. No. 7,993,366, incorporated by reference.

[0150] (Intervention Device - Suction Catheter) A wide variety of interventional devices may be used in conjunction with the disclosed system, such as for insertion through the arterial access device 110. For example, the interventional device may be an aspiration catheter formed with an elongated body, with an optional proximal end and a distal end, with at least one opening formed at or near the proximal end and at least one opening formed at or near the distal end, and with a lumen therethrough. In a non-limiting example, the aspiration catheter has an inner diameter of 0.071 inches, 0.058 inches, 0.045 inches, or in a range thereabout. In another non-limiting example, the aspiration catheter has a length of 58 centimeters or about 58 centimeters. The aspiration catheter may have an overall length of about 67 cm or about 63 cm and / or a working length of about 62 cm or 58 cm. The aspiration catheter may have an outer diameter of about 0.069 inches or about 0.082 inches. In one embodiment, the interventional device is a 0.088 inch catheter with respect to the inner lumen of the catheter. The distal sheath 605 of the arterial access device 110 may have an inner diameter of 0.088 inches, or an inner diameter of 0.058 inches. Alternatively, in non-limiting examples, the inner diameter may be in the range of 0.07 inches.

[0151] Various interventions may be used with the disclosed system, such as inserting an interventional device through the arterial access device 110 to perform a treatment. For example, the interventional device may include an aspiration catheter to perform localized aspiration at a location distal to the sheath 605 of the arterial access device 110, such as to capture and remove a thrombus within the blood vessel. For example, the aspiration catheter may be sized and shaped or otherwise configured to be inserted through the hemostasis valve 625, as well as the proximal extension 610 and the sheath 605, to access a treatment site within the blood vessel. The aspiration catheter may use a previously placed guidewire or other device to facilitate placement of the distal opening of the aspiration catheter proximate the obstruction. Once the distal opening of the aspiration catheter is positioned at or near the treatment site, the aspiration catheter may be used to apply suction to the thrombus to capture and remove it from the patient. For example, the aspiration catheter may be connected to a source of aspiration, such as a pump or syringe.

[0152] In some embodiments, the arterial access device 110 and aspiration catheter may be configured to access any number of various blood vessels, including the common carotid artery CCA and / or the femoral artery. For example, the aspiration catheter may be introduced into the vasculature for retrieval of occlusion (e.g., thrombus) from either the carotid artery access site or the femoral artery access site. As described above, the arterial access device 110 may include a flow control assembly 125 and a shunt 120 connectable to a mechanism for passive or active backflow. For example, backflow may be performed during aspiration of occlusion using any of the aspiration catheter embodiments described herein.

[0153] 20A-20B illustrate an embodiment of an aspiration catheter 2100 having an elongate body 2110 and an inner lumen 2112 extending between a distal body end 2114 and a proximal body end 2116 of the elongate body 2110. In some embodiments, the elongate body 2110 is formed of a flexible material. The proximal body end 2116 may be configured to connect to a suction source, such as an active or passive suction mechanism (e.g., a pump, a syringe). The inner lumen 2112 may be defined by an inner wall 2126. The distal body end 2114 has a distal opening 2120 defined at least in part by the inner lumen 2112. The distal opening 2120 may provide localized suction at a location distal to the distal-most end of the arterial access device 110, such as to capture and remove thrombus from a blood vessel.

[0154] 20A-20B, the distal opening 2120 has a suction region 2122 in fluid communication with a suction source for applying suction to an obstruction, such as a thrombus, to capture and remove the obstruction. For example, the suction region 2122 may be defined as the cross-sectional area of ​​the inner lumen 2112 at the distal body end 2114. As such, the suction region 2122 may be determined based on the diameter of the distal opening 2120 and / or the circumference 2124 of the inner lumen 2112 at the distal body end 2114. The inner lumen 2112 may be defined by an inner wall 2126.

[0155] For example, as the circumference 2124 defining the distal opening 2120 increases, the suction area 2122 increases, thereby increasing the amount of suction force that can be applied to the thrombus. The greater the suction force by the aspiration catheter 2100, the more efficient and effective the retrieval and removal of the thrombus by the aspiration catheter 2100. Reliably capturing and removing the thrombus is important to return blood flow to the vessel and reduce the adverse effects of the occlusion on the body. At least some of the current occlusion retrieval / removal devices require at least two attempts to capture the occlusion for removal. Unsuccessful attempts to remove the occlusion result in longer periods of time during which blood flow along a portion of the body is stopped, increasing the likelihood of adverse physical and / or cognitive effects. However, while a larger suction area 2122 can improve the treatment of the occlusion and patient outcomes, the size and shape of the suction catheter 2100, including the distal body end 2114 of the aspiration catheter 2100, may be limited by the arterial access device 110 and the one or more blood vessels along which the aspiration catheter 2100 travels to treat the occlusion.

[0156] Described below are various embodiments of the aspiration catheter 2100 having various distal features (e.g., deformers, distal opening periphery, obstruction gripping portion) that provide improved suction area 2122 and / or obstruction capture / removal to achieve more efficient and effective aspiration of thrombus and restoration of blood flow along one or more diseased blood vessels. As described in more detail below, some embodiments of the aspiration catheter 2100 have an expandable distal portion, such as when positioned at a treatment location. Such expansion of the distal portion can increase the suction area 2122 provided by the aspiration catheter 2100 at the treatment location to achieve greater suction force. As a result, the aspiration catheter can be inserted into and travel along one or more blood vessels with a smaller diameter while still efficiently and effectively capturing and removing thrombus from the patient. In some embodiments, the suction catheter 2100 has a distal end (e.g., distal body end 2114) that has a shape that provides a longer length to the periphery 2124 of the distal opening 2120, thereby creating a larger suction area 2122 without changing the diameter of the distal opening 2120. Various suction catheters 2100 are described herein that have other features and functions, such as an obstruction gripper.

[0157] In some embodiments, the aspiration catheter 2100 has at least one reinforcing member to reduce flexibility and increase structural strength along at least a portion of the elongate body 2110 to aid in advancement and positioning of the aspiration catheter 2100. For example, the reinforcing member may extend along a first length of the elongate body 2110 between a proximal reinforcing end and a distal reinforcing end. For example, the proximal reinforcing end may be disposed at or adjacent to the proximal body end 2116 of the elongate body 2110. Further, the distal reinforcing end may be disposed a second length from the distal body end 2114 of the elongate body 2110. Thus, in some embodiments, the second length of the elongate body 2110 may remain flexible and define an expandable distal portion of the elongate body 2110, as described in more detail below.

[0158] For example, the expandable distal portion may be expanded at or adjacent to the obstruction to increase the diameter of the distal opening 2120, thereby increasing the area of ​​suction 2122 that may be applied to the obstruction to efficiently and effectively capture and remove the obstruction. Such capture of the obstruction may include activating a suction source to apply a vacuum to the distal opening 2120. Capture of the obstruction by the suction device 2100 may include holding the obstruction at and / or within the distal opening 2120 (e.g., using suction and / or obstruction capture functions). For example, the obstruction may be captured at or within the distal opening 2120 and / or distal portion. The suction catheter 2100 may then be withdrawn once the obstruction has been sufficiently removed and / or captured to allow blood flow back to the affected vessel.

[0159] The embodiments of the suction catheter 2100 described herein may be made of one or more of a variety of materials, including a variety of materials to achieve desired characteristics. For example, one or more reinforcing members may be made of metal wire and / or Teflon material. In some embodiments, at least a distal portion of the elongate body 2110 of the suction catheter 2100 may be made of a flexible material, such as a tie layer. For example, the flexible material forming at least a portion of the expandable distal portion may be elastic to allow circumferential expansion at the distal opening 2120.

[0160] In some embodiments, at least a distal portion of the elongate body 2110 may include one or more liquid crystal polymer (LCP) fibers, which may promote wall strength without significantly affecting flexibility. Various embodiments of the aspiration catheter 2100 to achieve improved capture and / or removal of obstructing material to efficiently and effectively restore blood flow are described in more detail below.

[0161] 21A-21D illustrate an embodiment of an aspiration catheter 2200 comprising an embodiment of an elongate body 2110 having an expandable distal portion 2230. The aspiration catheter 2200 of Figures 21A-21D may have the same or similar features and functions as described above with respect to the aspiration catheter 2100 of Figures 20A-20B. Additionally, the expandable distal portion 2230 of the elongate body 2110 may be flexible and deformable such that the distal opening 2120 increases in diameter, thereby increasing the suction area 2122 of the distal opening 2120, as described in more detail below.

[0162] As shown in FIG. 21A, the suction catheter 2200 may include one or more reinforcing members 2240 extending along the first length 2250 of the elongate body 2110. For example, the reinforcing member 2240 may include a metal wire 2241 that extends helically along the inner wall 2126 of the first length 2250 of the elongate body 2110. Additionally, the reinforcing member 2240 may include a Teflon liner 2242 that extends along the inner diameter of the helical metal wire 2241, as shown in FIGS. 21A and 21C. For example, the reinforcing member 2240 may extend along the first length 2250 of the elongate body 2110 between a proximal reinforcing end and a distal reinforcing end. For example, the proximal reinforcing end may be disposed at or adjacent to the proximal body end 2116 of the elongate body 2110. The distal reinforcing end may be disposed a second length 2255 away from the distal body end 2114 of the elongate body 2110. In this manner, the second length 2255 may remain flexible and define at least a portion of the expandable distal portion 2230 of the elongate body 2110. Additionally, each of the one or more reinforcing members 2240 may extend along various lengths of the elongate body 2110 proximate the second length 2255 without departing from the scope of the present disclosure.

[0163] In some embodiments, one or more LCP fibers may extend along the flexible second length 2255 of the elongate body 2110 and help increase wall strength without significantly affecting the flexibility of the elongate body 2110 along the second length.

[0164] As shown in FIGS. 21A-21D, the suction catheter 2200 may include a deformer, such as an inflatable balloon 2260, coupled to and extending along the second length 2255 of the elongate body 2110. For example, the inflatable balloon 2260 may extend along the longitudinal axis of the elongate body 2110 and along the outer wall of the elongate body 2110. For example, the inflatable balloon 2260 may be retained (e.g., glued) to the elongate body 2110 at one or more locations, such as at the distal end and / or proximal end of the second length 2255. In some embodiments, the inner diameter of the inflatable balloon 2260 may be approximately the same as the outer diameter of the elongate body 2110 (e.g., along the second length). As shown in FIG. 21A, the inflatable balloon 2260 may form a deflated configuration. Also, as shown in FIG. 21C, the inflatable balloon 2260 may form an inflated configuration. In the expanded configuration, the expandable distal portion 2230 (e.g., the second length 2255 of the elongate body 2110) can deform distally and increase in diameter, thereby increasing the diameter of the distal opening 2120 compared to when the inflatable balloon 2260 is in the deflated configuration.

[0165] 21A and 21C, the inflatable balloon 2260 can be in fluid communication with a fill line 2262 extending from a proximal end of the elongate body 2110 and can provide a fluid (e.g., saline, contrast solution) to the inflatable balloon 2260 to enable the inflatable balloon 2260 to form an inflated configuration. The fill line 2262 can also provide a fluid passageway for ejecting a fluid to enable the inflatable balloon 2260 to form a deflated configuration.

[0166] For example, as shown in FIG. 21B, when the inflatable balloon 2260 is in a deflated configuration, the distal opening 2120 forms a first suction region 2122a and has a diameter approximately the same as the diameter of the elongate body 2110 along the first length 2250. As shown in FIG. 21D, in an expanded configuration, the inflatable distal portion 2230 may increase in diameter such that the distal opening 2120 forms a second suction region 2122b (e.g., having a second opening diameter) that is larger than the first suction region 2122a (e.g., having a first opening diameter). For example, as the fill line supplies fluid to the inflatable balloon 2260 and the inflatable balloon 2260 expands, the inflatable balloon 2260 may expand radially, thereby deforming and radially expanding the inflatable distal portion 2230. The radial expansion of the expandable distal portion 2230 results in a larger diameter distal opening 2120 (e.g., the diameter of the second opening is larger than the diameter of the first opening) and a larger suction area 2122 (compared to when the balloon 2260 is in a deflated configuration), allowing the suction catheter 2200 to apply a greater suction force to retrieve the obstruction material. Suction may be activated when the balloon 2260 is in an inflated configuration to capture the obstruction material at or within the expandable distal portion 2230 for removal from the blood vessel.

[0167] 22A-22D illustrate another embodiment of the suction catheter 2300 having an embodiment of an expandable distal portion 2230. The suction catheter of FIGS. 22A-22D may have the same or similar features and functions as described above with respect to the suction catheter 2200 of FIGS. 21A-21D. Additionally, as shown in FIGS. 22A and 22C, the inflatable balloon 2360 of the suction catheter 2300 may extend helically around and along the second length 2255. As such, the inflatable balloon 2360 of FIGS. 22A-22D may have a smaller diameter and a longer length as compared to the inflatable balloon 2260 of FIGS. 21A-21D.

[0168] 22B, when the inflatable balloon 2360 is in a deflated configuration, the distal opening 2120 can form a first suction region 2122a and has approximately the same diameter as the diameter of the elongate body 2110 along the first length 2250. In an expanded configuration, as shown in FIGS. 22C and 22D, the inflatable distal portion 2230 can deform distally and increase in diameter as a result of the inflatable balloon 2360 forming an expanded configuration, such that the distal opening 2120 forms a second suction region 2122b that is larger than the first suction region 2122a.

[0169] 23A-23D illustrate another embodiment of the suction catheter 2400 comprising an embodiment of the elongate body 2110 having an expandable distal portion 2230. The suction catheter 2400 of FIGS. 23A-23D may have the same or similar features and functions as described above with respect to the suction catheter 2100 of FIGS. 21A-21D. Additionally, the inflatable balloon 2460 of the suction catheter 2400 shown in FIGS. 23A-23D may extend helically around and along the second length 2255 and may be twisted along at least a portion of the length of the balloon 2460 that extends helically about the second length 2255. The inflatable balloon 2460 of FIGS. 23A-23D may thereby have a smaller diameter and a longer length as compared to the inflatable balloon 2260 of FIGS. 21A-21D. Further, due to the twisting of the inflatable balloon 2460, the inflatable balloon 2460 of Figures 23A-23D can have a longer length as compared to the inflatable balloon 2260 of Figures 22A-22D. For example, a longer balloon length can contribute to a greater expansion of the expandable distal portion 2230 to create a larger suction area 2122, such as when the inflatable balloon 2460 is in an expanded configuration, as shown in Figures 23C and 23D. Figures 23A and 23D show the inflatable balloon 2460 twisted and spiraling around the second length 2250 in an expanded configuration.

[0170] In some embodiments, the second length 2255 may be between about 1 millimeter (mm) and about 5 mm in length. In some embodiments, the second length 2255 may be between about 0.5 and 2 times the diameter of the elongate body 2110. In some embodiments, the inflatable balloon may be spirally wrapped about 1 to about 5 times around the second length 2255 of the elongate body 2110. The inflatable balloon may be made of a variety of materials, such as one or more of a biocompatible or compliant material, such as polyurethane or silicone.

[0171] In some embodiments of the suction catheter, a balloon is not used to deform (e.g., expand) the expandable distal portion 2230, as discussed in more detail below. For example, the suction catheter may include a deformer having a shape memory deformer disposed along and / or coupled to the second length 2255. For example, the shape memory deformer may be configured to form a folded configuration and an expanded configuration, such as to form a larger suction area 2122 when the shape memory deformer is in the expanded configuration. For example, when the shape memory deformer is in the folded configuration along the second length 2255, the distal opening 2120 can form a first suction area 2122a and have approximately the same diameter as the diameter of the elongate body 2110 along the first length 2250. In the expanded configuration, the shape memory deformer can deform the expandable distal portion 2230 to a larger diameter such that the distal opening 2120 forms a second suction area 2122b that is larger than the first suction area 2122a.

[0172] In some embodiments, the shape memory deformer may include at least one Nitinol material, such as Nitinol wire, extending along the second length 2255. For example, the Nitinol wire may be configured to form a folded configuration when the Nitinol wire is at or below a first temperature (e.g., body temperature) and to form an expanded configuration when the Nitinol wire reaches and / or exceeds the first temperature. Other temperatures may be pre-set to cause the Nitinol wire to form the folded and expanded configurations. For example, some embodiments of the aspiration catheter may include a thermally and / or electrically conductive wire that may extend between the shape memory deformer and a power source. Thereby, in some embodiments, an electric current may be provided along the conductive wire to increase the temperature of the Nitinol wire to transition the Nitinol wire to the expanded configuration. Other shape memory members and formations of Nitinol material are within the scope of this disclosure.

[0173] 24A-24D illustrate another embodiment of an aspiration catheter 2500 comprising an embodiment of an elongate body 2110 having an expandable distal portion 2230. The aspiration catheter 2500 of FIGS. 24A-24D has the same or similar features and functions as described above with respect to the aspiration catheter 2100 of FIGS. 21A-21D. However, instead of an inflatable balloon 2260 extending along the second length 2255 to deform (e.g., expand) the expandable distal portion 2230, the aspiration catheter 2500 of FIGS. 24A-24D includes a shape memory deformer 2570 that is transitionable between a collapsed configuration, as shown in FIGS. 24C-24D, and an expanded configuration, as shown in FIGS. 24A-24B.

[0174] For example, the shape memory deformer 2570 may comprise at least one nitinol wire 2572 extending longitudinally along the second length 2255 of the elongate body 2110. As shown in FIGS. 24A-24D, the nitinol wire 2572 may extend longitudinally at multiple radial positions along the second length 2255. In some embodiments, the nitinol wire 2572 may extend along the inner wall 2126 of the inner lumen 2112 of the elongate body 2110 and / or along the outer wall of the elongate body 2110. An additional material sheath 2574 may extend over the nitinol wire 2572 to position the nitinol wire 2572 between the material sheath 2574 and the second length 2255 of the elongate body 2110. As discussed above, the shape memory deformer 2570 may transition between a collapsed configuration and an expanded configuration based on the temperature of the shape memory deformer 2570. In some embodiments, the nitinol wire 2572 may bend radially outward to form an expanded configuration when the nitinol wire 2572 reaches body temperature, as shown in Figures 24A and 24B.

[0175] For example, when the shape memory deformer 2570 is in a collapsed configuration along the second length 2255, as shown in Figures 24C and 24D, the distal opening 2120 can form a first suction region 2122a and have approximately the same diameter as the diameter of the elongate body 2110 along the first length 2250. In an expanded configuration, the shape memory deformer 2570 can deform the expandable distal portion 2230 to a larger diameter such that the distal opening 2120 forms a second suction region 2122b that is larger than the first suction region 2122a.

[0176] 25A-25D illustrate another embodiment of an aspiration catheter 2600 comprising an embodiment of an elongate body 2110 having an expandable distal portion 2230. The aspiration catheter 2600 of FIGs. 25A-25D has the same or similar features and functionality as any one of the embodiments of the aspiration catheter disclosed herein. For example, the aspiration catheter 2600 may comprise an embodiment of a shape memory deformer 2670 that is transitionable between a collapsed configuration, as shown in FIGs. 25C-25D, and an expanded configuration, as shown in FIGs. 25A-25B.

[0177] As shown in FIGS. 25A-25D, the shape memory deformer 2670 may comprise a stent retriever 2675 disposed along the second length 2255, such as embedded between the inner wall 2126 of the elongate body 2110 and a sheath of material 2574. For example, the stent retriever 2675 may comprise at least one Nitinol wire 2572 extending in one or more directions and at one or more angles relative to the longitudinal axis of the inner lumen 2112. As shown in FIGS. 25A and 25C, the stent retriever 2675 may comprise a braided or woven Nitinol wire 2572. As described above, the shape memory deformer 2670 may transition between a collapsed configuration and an expanded configuration based on the temperature of the shape memory deformer 2670. For example, the braided nitinol wires 2572 of the stent retriever 2675 can move closer to being parallel to the longitudinal axis of the inner lumen 2112 when moving to a collapsed configuration, as shown in Figure 25C. Additionally, the nitinol wires 2572 of the stent retriever 2675 can move to be more angled relative to the longitudinal axis when moving to an expanded configuration, as shown in Figure 25A, such as when the nitinol wires 2572 reach a preset temperature (e.g., body temperature).

[0178] For example, when the shape memory deformer 2670 is in a collapsed configuration along the second length 2255, the distal opening 2120 can form a first suction region 2122a and have approximately the same diameter as the diameter of the elongate body 2110 along the first length 2250. In an expanded configuration, the shape memory deformer 2670 can deform the expandable distal portion 2230 to a larger diameter such that the distal opening 2120 forms a second suction region 2122b that is larger than the first suction region 2122a.

[0179] 26A-26D show another embodiment of the suction catheter 2700 having an expandable distal portion 2230 of the elongate body 2110. The suction catheter 2700 of FIGS. 26A-26D has the same or similar features and functions as any one of the embodiments of the suction catheter disclosed herein. Furthermore, the suction catheter 2700 of FIGS. 26A-26D includes a movable deformer 2770 that is movable relative to the elongate body 2110. For example, the movable deformer 2770 can form a folded configuration, as shown in FIGS. 26C-26D, when disposed along the first length 2250 (including the reinforcing member 2240) of the elongate body 2110, and can form an expanded configuration, as shown in FIGS. 26A-26B, when disposed along the flexible second length 2255 having the expandable distal portion 2230 of the elongate body 2110.

[0180] For example, the movable deformer 2770 may comprise a movable stent retriever 2775 positionable to be slidably controlled by a physician (e.g., via a connecting feature 2776) along the first length 2250 and / or the second length 2255. For example, the movable stent retriever 2775 may comprise at least one Nitinol wire 2572 extending in one or more directions and at one or more angles relative to the longitudinal axis of the inner lumen 2112. As shown in FIGS. 26A and 26C, the movable stent retriever 2775 may comprise a radially expandable braided or braided Nitinol wire 2572 (e.g., formed into an expandable basket) such that when the movable stent retriever 2775 is positioned along the flexible second length 2255, the movable stent retriever 2775 can radially expand to enlarge the distal opening 2120 and form a larger suction area 2122. For example, the movable stent retriever 2775 may form an expanded configuration when the movable stent retriever 2775 reaches a preset temperature (e.g., body temperature). Retrieval and removal of obstruction material (using suction) can be performed with the stent retriever positioned along the second length 2255.

[0181] 27A-27D illustrate another embodiment of an aspiration catheter 2800 having an expandable distal portion 2230 of the elongate body 2110. The aspiration catheter 2800 of FIGS. 27A-27D has the same or similar features and functionality as any one of the embodiments of the aspiration catheter disclosed herein, including a movable deformer 2870 that is translatable relative to the elongate body 2110. For example, the movable deformer 2870 can form a folded configuration, as shown in FIGS. 27C-27D, when positioned along the first length 2250 of the elongate body 2110 (including the reinforcing member 2240), and can form an expanded configuration, as shown in FIGS. 27A-27B, when positioned along the second length 2255 of the elongate body 2110.

[0182] For example, the movable deformer 2870 may comprise a movable dilator 2877 positionable to be slidably controlled by a physician within the inner wall 2126 of the elongate body 2110 along the first length 2250 and / or the second length 2255. For example, the movable dilator 2877 may comprise a tubular body having a plurality of longitudinal slits 2878 forming a distal extension 2879. At least a distal end of the movable dilator 2877 having the distal extension 2879 may be formed of a shape memory material (e.g., Nitinol) such that when the distal extension 2879 is positioned along the flexible second length 2255, the slits 2878 cause the distal extension 2879 to radially expand, thereby expanding the distal opening 2120 to form a larger suction area 2122, as shown in FIGS. For example, the movable dilator 2877 may form an expanded configuration when the movable dilator 2877 reaches a preset temperature (e.g., body temperature). Retrieval and removal (using suction) of obstruction material may be accomplished with the movable dilator 2877 disposed along the second length 2255.

[0183] For example, the movable deformer 2870 may be restricted from deforming (e.g., expanding) when disposed along the second length 2255 (e.g., non-stretchable / non-deformable) and allowed to deform (e.g., expand) when disposed along the first length 2250 (e.g., stretchable / deformable) after reaching a preset temperature. Thus, a user can wait to move the movable deformer (such as the expandable movable deformer 2770 and / or 2870) to a position along the second length 2255 when deformation and expansion of the expandable distal portion 2230 is desired. A vacuum source can apply a vacuum along the elongate body and / or along the movable deformer (such as the expandable deformer 2770 and / or 2870) to suck at least a portion of the occlusion into the movable deformer in the expanded configuration.

[0184] 28A-B illustrate another embodiment of an aspiration catheter 2900 having an embodiment of a distal opening 2120 that has a fixed diameter and therefore does not expand. Additionally, the aspiration catheter 2900 of FIGS. 28A-B has the same or similar features and functions as any one of the embodiments of the aspiration catheter disclosed herein, such as including one or more reinforcing members 2240 along at least a portion of the elongate body 2110. However, instead of having an expandable distal portion to form a larger suction area 2122, the aspiration catheter 2900 of FIGS. 28A-B includes a shaped distal end 2980. The shaped distal end 2980 includes a periphery 2124 that forms a suction seal between the periphery 2124 and the obstruction such that a vacuum may be applied to the elongate body 2110 to aspirate at least a portion of the obstruction into the distal opening 2120. The periphery 2124 may extend outwardly in a single plane, such as forming a multiple angled shape 2981 (eg, a triangle) that extends longitudinally relative to the longitudinal axis of the inner lumen 2112, as shown in FIG. 28A.

[0185] For example, the periphery 2124 may have at least four angled features 2981 that are approximately equally spaced along the periphery 2124. Such multiple angled features 2981 along the periphery 2124 may increase the length of the periphery 2124, for example, as compared to when the periphery 2124 extends along a single plane. The longer length of the periphery 2124 of the distal opening 2120 may thereby create a larger three-dimensional suction area 2122 as compared to a distal opening 2120 having a periphery 2124 that extends along a single plane (e.g., a two-dimensional suction area 2122). As discussed above, by increasing the suction area 2122 of the distal opening 2120, a greater suction force may be applied to the obstruction, thereby allowing for more efficient and effective retrieval and removal of the obstruction (and restoration of blood flow). Various shapes can be formed along the periphery 2124 of the distal opening 2120 to increase the length of the periphery 2124 and the suction area 2122 .

[0186] 29A-29B illustrate another embodiment of an aspiration catheter 3100 having a fixed diameter (non-expanding) distal opening 2120 and an embodiment of a shaped distal end 2980. As described above, the shaped distal end 2980 has a periphery 2124 that forms a suction seal between the periphery 2124 and an obstruction such that a vacuum is applied to the elongate body 2110 to aspirate at least a portion of the obstruction into the distal opening 2120. The periphery 2124 may extend outwardly in a single plane, such as forming a plurality of rounded shapes 3181 (e.g., circular, sinusoidal) that extend longitudinally relative to the longitudinal axis of the inner lumen 2112, as shown in FIG.

[0187] For example, the periphery 2124 may include at least four rounded shapes 3181 that are approximately equally spaced along the periphery 2124. Such multiple rounded shapes 3181 along the periphery 2124 may increase the length of the periphery 2124, for example, as compared to a periphery 2124 that extends along a single plane. The longer length of the periphery 2124 of the distal opening 2120 may thereby create a larger three-dimensional suction area 2122 as compared to a distal opening 2120 having a periphery 2124 that extends along a single plane (e.g., a two-dimensional suction area 2122). As discussed above, by increasing the suction area 2122 of the distal opening 2120, a greater suction force may be applied to the obstruction, thereby allowing for more efficient and effective retrieval and removal of the obstruction (and restoration of blood flow). Other shapes and configurations may be formed along the periphery 2124 of the distal opening 2120 to increase the length of the periphery 2124 and the suction area 2122 without departing from the scope of the present disclosure. Additionally, while the elongate body 2110 is shown as having a circular cross-section, it may have other shapes, such as elliptical. As such, the periphery 2124 and / or the distal opening 2120 may form a circular, elliptical, or other shape without departing from the scope of the present disclosure.

[0188] 30A-30B illustrate another embodiment of an aspiration catheter 3200 having a fixed diameter (non-expanding) distal opening 2120 and an embodiment of an obstruction gripping portion 3290. As shown in FIG. 30A, a first length 2250 of the elongate body 2110 includes a reinforcing member 2240, such as a helical metal wire 2241, embedded within an inner wall 2126 of the elongate body 2110. As also shown in FIG. 30A, a second length 2255 extending along a distal end of the elongate body 2110 may include an obstruction gripping portion 3290 having an internal exposed coil 3292 extending along the inner wall 2126 and configured to engage and capture a thrombus, such as by rotating the aspiration catheter 3200 to capture and remove the thrombus. In some embodiments, the internal exposed coil 3292 has the same or similar material and / or construction as the reinforcing member 2240 extending along the first length 2250. For example, the internal exposed coil 3292 may be made of one or more of stainless steel and nitinol. In some embodiments, the internal exposed coil 3292 extends from about 1 centimeter (cm) to about 2 centimeters along the second length 2255. In some embodiments, LCP fibers extend along the second length 2255 to provide additional wall strength.

[0189] For example, during use of the aspiration catheter 3200, suction can be applied to the elongate body 2110, which can pull adjacent thrombus at least partially through the distal opening 2120. The aspiration catheter 3200 can then be rotated to allow the internal exposed coil 3292 of the occlusion gripping portion 3290 to fragment the thrombus into smaller pieces for aspiration and / or capture a portion of the thrombus to enable reliable removal of the thrombus from the vasculature.

[0190] Any one of the aspiration catheters described herein may include LCP fibers along at least the second length 2255 to promote wall strength without significantly reducing the flexibility of the elongated body 2110 along the second length 2255. For example, wall strength of an aspiration catheter is important for efficient and effective navigation of the aspiration catheter along one or more of the various blood vessels to reach the thrombus. Additionally, an aspiration catheter may have a thin wall thickness to achieve a desired size and flexibility, but such a thin wall may adversely affect the ability of the aspiration catheter to withstand high pressure injection. Thus, by adding one or more layers of LCP fibers along at least the portion of the elongated body 2110 that does not include a reinforcing member, the LCP fibers may provide structural support without significantly reducing flexibility or increasing wall thickness.

[0191] Additionally, as the catheter diameter increases, the cross-sectional strength of the catheter wall may be increased and structural support may be required. Increasing the thickness of the catheter wall may provide additional structural support, but may result in a stiffer catheter and a smaller diameter inner lumen 2112. For this reason, LCP fibers may be added to at least a portion of the aspiration catheter without significantly affecting the flexibility of the catheter along such portion. The LCP fibers may extend in a variety of directions and configurations, including longitudinally and / or at angles relative to the longitudinal axis of the inner lumen 2112.

[0192] 31A-31B illustrate another embodiment of an aspiration catheter 3300 including a plurality of LCP fibers 3395 extending along the length of the elongate body 2110. For example, the LCP fibers 3395 include at least one longitudinally oriented LCP fiber 3395a and at least one circumferentially oriented LCP fiber 3395b, as shown in FIG. 31A. The LCP fibers can form at least one layer along the length of the elongate body 2110. For example, a first layer includes circumferentially oriented LCP fibers 3395b and a second layer includes longitudinally oriented LCP fibers 3395a. Various numbers of layers of LCP fibers 3395 oriented in one or more directions are within the scope of the present disclosure.

[0193] For example, longitudinally oriented LCP fibers 3395a can provide additional tensile strength and circumferentially oriented LCP fibers 3395b can increase burst strength. Such additional tensile strength and increased burst strength can be achieved along at least the portion of the elongate body 2110 along which the LCP fibers extend. In some embodiments, the LCP fibers may extend along the length of the elongate body 2110 with one or more reinforcing members 2240, such as metal wires 2241, as shown in FIG.

[0194] Although the present specification contains many specifics, these should not be construed as limiting the scope of the invention as claimed or as being claimed, but rather as a description of features specific to a particular embodiment. Certain features described herein in the context of separate embodiments may be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment may be implemented in multiple embodiments separately or in any suitable subcombination. Furthermore, although features may be described above as acting in a particular combination and may initially be claimed as such, one or more features from the claimed combination may in some cases be deleted from the combination, and the claimed combination may be directed to a subcombination or a variation of the subcombination. Similarly, although operations are depicted in the figures in a particular order, this should not be understood as requiring such operations to be performed in the particular order shown, or in a sequential order, or all of the operations depicted, to achieve desired results.

[0195] Although various method and apparatus embodiments have been described in detail herein with reference to specific versions, it should be understood that other versions, embodiments, methods of use, and combinations thereof are possible, and therefore the spirit and scope of the appended claims should not be limited to the description of the embodiments contained herein.

Claims

1. A suction catheter configured to remove a thrombus from a patient's blood vessel, An elongated body formed of a flexible material and having an inner lumen extending between a proximal body end and a distal body end, the inner lumen being defined by an inner wall and forming a distal opening at the distal body end, the elongated body; A reinforcing member extending along a first length of the elongated body between a proximal reinforcing end and a distal reinforcing end, the distal reinforcing end being disposed at a second length from the distal body end of the elongated body, the reinforcing member; A deformator extending along the second length of the elongated body, the deformator having a first opening diameter when the deformator forms a first configuration and a second opening diameter when the deformator forms a second configuration, the second opening diameter being larger than the first opening diameter, the deformator coupled to the second length; A suction catheter comprising:

2. The suction catheter according to claim 1, wherein the deformator comprises an inflatable balloon.

3. The suction catheter according to claim 2, wherein the inflatable balloon extends spirally along the second length of the elongated body.

4. The suction catheter according to claim 2, wherein the inflatable balloon is twisted along the second length of the elongated body.

5. The distal opening forms a first suction region when the inflatable balloon is in the first configuration and a second suction region when the inflatable balloon is in the second configuration, the second suction region being larger than the first suction region, the suction catheter according to claim 2.

6. The suction catheter according to claim 5, wherein the first suction region and the second suction region are each defined by one or more of the diameter and cross-sectional area of the distal opening.

7. The suction catheter according to claim 5, wherein the inflatable balloon contracts when in the first configuration and expands when in the second configuration.

8. The suction catheter according to claim 1, wherein the deformator comprises a shape memory member.

9. The suction catheter according to claim 8, wherein the shape memory member comprises a nitinol material that transitions between the first configuration and the second configuration based on the temperature of the shape memory member.

10. The suction catheter according to claim 8, wherein the shape memory member includes at least one nitinol wire extending in the longitudinal direction along the second length.

11. The suction catheter according to claim 8, wherein the shape memory member includes a stent retriever.

12. The suction catheter according to claim 1, wherein a portion of the elongated body along the second length has greater flexibility than a portion along the first length.

13. The suction catheter according to claim 1, wherein the reinforcing member includes one or more of a Teflon liner and a metal wire.

14. The suction catheter according to claim 1, further comprising a plurality of LCP fibers extending along the second length of the elongated body.

15. The suction catheter according to claim 14, wherein a first LCP fiber of the plurality of LCP fibers is oriented longitudinally along the elongated body, and a second LCP fiber of the plurality of LCP fibers is oriented circumferentially along the elongated body.

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