Endovascular variable aortic control catheter

Endovascular variable aortic control catheters (EVACC) are provided that are adapted to augment upstream blood pressure and regulate downstream blood flow for patients in shock. The EVACC devices provide improved treatment for truncal wounds, which may be used for example on a battlefield, thereby increasing survivability of injured soldiers. The devices are a catheter-based system having a proximal hand piece for controlled deployment of the device through a delivery sheath. A collapsible, wire framework supports an expandable and collapsible occlusion barrier. The wire basket and occlusion barrier expand to fit within the lumen of the aorta. Various movable elements are used to adjust an adjustable passageway to regulate controlled anterograde blood flow.

FIELD OF THE INVENTION

This disclosure relates generally to endovascular aortic occlusion devices deployed within the aorta. More particularly, the invention relates to endovascular aortic occlusion devices adapted for augmenting blood pressure and controlling blood flow downstream of the occluded region.

BACKGROUND

Death from the complications of truncal hemorrhage continues to exist as a high probability in an overwhelming number of cases in both the military and civilian medical spheres. Existing systems and procedures used to control truncal hemorrhage frequently contribute to a patient's ultimate death through inability to maintain adequate blood flow to vital organs. It is well recognized that without controlled distal reperfusion, hemodynamic collapse is common, particularly where open aortic cross-clamping is used to stop hemorrhage. The ability to rapidly deliver effective, variable, and adaptive control of aortic flow for hemorrhaging patients will save innumerable lives.

Mitigation of battlefield injury and hemorrhage is a high priority of U.S. military trauma surgeons and researchers. Uncontrolled blood loss is recognized as the leading cause of death in 90 percent of the potentially survivable battlefield cases and in 80 percent of those who died in a military treatment facility. “Bleed-outs,” especially those caused by groin or neck wounds, challenge medics, corpsmen and physicians who can do little to stop blood loss caused by major arterial injuries.

Two devices, the Combat Ready Clamp and Abdominal Aortic Tourniquet, have been built to treat truncal injuries. The Combat Ready Clamp is primarily for treating junctional hemorrhage (i.e. between the trunk and an extremity). The Combat Ready Clamp is ineffective against wounds involving the genital region or the loss of both legs. The Abdominal Aortic Tourniquet functions as a large blood pressure cuff which wraps around the lower torso to minimize extremity bleeding.

Limiting or stopping blood flow through the major blood vessel of the body, the aorta, is an established method for slowing the rate of blood loss in a severely injured patient with ongoing bleeding. In the military, this aortic occlusion has traditionally been achieved using a large aortic clamp inserted into the chest cavity via a large incision between the ribs. This dramatic and extremely invasive maneuver is typically a “last ditch” effort. The clamping of the aorta excludes the systemic circulation, by definition, thus causing an ischemia. The goal of the aortic clamping procedure is to keep the patient's remaining blood circulating to the heart, lungs, and brain for precious minutes until bleeding below the aortic clamp is controlled and the patient can be resuscitated and systemic circulation restored. Because of the inherent morbidity of the aortic clamp maneuver, it is often reserved for only the sickest or moribund patients who have lost vital signs and are essentially already dead.

Recently, balloon catheters used in endovascular surgery have been repurposed to fully occlude the aorta by inflation of a balloon in the lumen of the aorta, as an alternative to aortic clamping. This procedure is referred to as Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA). REBOA has the potential to achieve effective aortic occlusion with less morbidity. Therefore, REBOA may be used earlier in the clinical course of the bleeding patient.

As with aortic clamping, REBOA can be used to increase blood pressure to vital organs while slowing ongoing blood loss. However, currently available FDA-approved balloon catheters used for REBOA can only reliably achieve complete occlusion or no occlusion. As such, attempting to wean a patient from complete balloon occlusion by slowly deflating the balloon is not achievable. When aortic occlusion is used in the course of treatment of a hemorrhaging patient, the physician must begin to wean the patient off complete occlusion as early as possible. Using REBOA, when the balloon is inflated, everything below the balloon quickly starts to die due to lack of blood flow. When the balloon is deflated to initiate flow, hemodynamic collapse is a possibility. Additionally, variation in patient size (height, weight, aortic diameter) limits the ability of a single REBOA catheter to effectively occlude aortic flow in all patients.

Currently, REBOA is performed utilizing devices largely intended for other purposes, specifically the FDA-approved CODA® balloon catheter (Cook Medical Technologies, LLC, Bloomington, Ind.) for occluding large blood vessels and molding of aortic endoprostheses. While effective at complete aortic occlusion, the CODA® balloon catheter is not ideally suited for partial vessel occlusion or controlled distal reperfusion during gradual deflation based on its inherent design characteristics, particularly an inability to create a variable and sustained pressure gradient across the balloon. An example of this type of device is disclosed by Eliason et al., U.S. Patent Application Publication No. 2013/0102926, published Apr. 25, 2013, which is incorporated by reference herein in its entirety. The invention of Eliason et al. is directed to a method for placing an aortic occlusion device without having to rely on fluoroscopy to ensure proper placement. The system of Eliason et al. relies on the use of an inflatable balloon to provide occlusion, and thus, has only marginal ability to control variability in flow from upstream to downstream of the occlusion device. Moreover, the system of Eliason et al. is unable to provide controlled anterograde blood flow (i.e., distal reperfusion).

It is well recognized that without controlled distal reperfusion, hemodynamic collapse is common. In particular, hemodynamic collapse has a high probability of occurrence when open aortic cross-clamping is used to staunch blood flow. Although complete occlusion can stop distal blood loss, complete occlusion also causes supraphysiologic blood pressure spikes to everything upstream of the occlusion balloon. These blood pressure spikes can worsen concomitant injuries to tissue beds proximal to the balloon (e.g. traumatic brain injury, pulmonary contusions and hemorrhage, or traumatic amputations of the upper extremities). Additionally, upon uncontrolled release of complete occlusion, the blood volume supplying the heart, lungs, and brain is rapidly redistributed to the lower half of the body effectively reducing the circulating blood volume. Additionally, peripheral vasodilation and the washout of toxic metabolites, which have built up in the ischemic tissues, can result in myocardial suppression and further deterioration of hemodynamics. As a result, the growing clinical experience with REBOA in its current form reveals negative physiologic effects.

The current compliant balloon architecture poses technical challenges for incremental restoration of distal reperfusion necessary to prevent hemodynamic collapse following complete aortic occlusion. As an alternative to compliant balloon architectures, there exist fixed-diameter, non-compliant balloon catheter designs (e.g., ARMADA® by Abbott Laboratories Corp., North Chicago, Ill.). However, these catheters are intended and approved for vessel dilation (angioplasty), typically for narrowed vessels (e.g., atherosclerosis). Additionally, a fixed-diameter, non-compliant balloon catheter must be sized appropriately to properly occlude each patient's aorta. Consequently, although the non-compliant balloon is less susceptible to change in shape due to blood pressure spikes, the inability to change diameter outside of a narrow range impedes its ability to serve as an adaptable device to support both complete occlusion and partial occlusion. Therefore, the relatively fixed diameter of non-compliant balloon catheters limits their real-world applicability across a range of normal aortic diameters.

Other efforts have been directed to development of potential alternative methods of providing aortic occlusion. For example, Barbut et al., U.S. Pat. No. 6,743,196, issued Jun. 1, 2004, describes a plurality of approaches to support aortic occlusion. Each approach described in Barbut et al. includes a catheter having a distally mounted constricting mechanism. Each constrictor is collapsed to facilitate insertion and then expanded once inserted to obstruct blood flow. Barbut et al. describes a constrictor comprising an outer conical shell and an inner conical shell, each having a distal open base and proximal apex. The outer shell further includes a pre-shaped ring to facilitate expansion. Both shells include ports or openings. Flow through the mechanism is controlled by rotating the inner conical shell such that the ports of each shell communicate.

More recently, VanCamp et al, in U.S. Pat. No. 7,927,346, issued Apr. 19, 2011, describes a device to provide temporary partial aortic occlusion to achieve diversion of blood flow to the brain in patients suffering from cerebral ischemia. The primary thrust of the VanCamp et al. invention is the provision of an occlusion device that does not require fluoroscopy to ensure proper placement. VanCamp's device includes an expandable frame with a planar membrane mounted on a first portion of the frame to occlude blood flow. In one embodiment disclosed in VanCamp et al., the membrane includes a fixed size opening in the center of the planar membrane to allow some blood to flow through the opening. Alternatively, VanCamp also discloses that the membrane itself may be somewhat permeable to blood flow to allow some flow. However, VanCamp is unable to provide variable control of blood flow during use.

In light of the aforementioned considerations and limitations of existing and proposed devices, there exists an urgent and unmet need for a viable solution to allow a physician to address hemorrhagic injuries and carefully regulate blood flow, from complete occlusion to sustained partial occlusion, with an ability to adjust the level of occlusion as the patient's vital signs dictate.

SUMMARY

The present invention, in its several embodiments, comprises a medical device to control blood flow and pressure in a patient having hemorrhagic blood loss from a traumatic truncal wound, hereinafter the endovascular variable aortic control catheter (“EVACC”) or “EVAC device”. The various embodiments of the EVACC enable adaptable and variable aortic occlusion for controlling anterograde blood flow and augmenting blood pressure to vital organs, particularly in patients suffering from significant blood loss. A relevant example is a patient presenting with a traumatic hemorrhagic event, such as a gunshot wound to the abdomen. The EVAC device provides variable levels of aortic occlusion to control distal aortic blood flow and pressure on either side of an occlusion barrier established by the device.

As used herein, the terms “proximal” and “distal” are from the perspective of the physician or other medical professionals, such that “proximal” describes a direction away from a patient, while “distal” describes a direction toward the patient. For example, the end of a device that is inserted into a patient would be considered the “distal end”; the end held by the physician would be considered the “proximal end”.

Further, as used herein, the terms “upstream” and “downstream” describe portions of the vascular system located on either side of the occlusion barrier. “Upstream” is in a direction away from the occlusion barrier toward the heart and associated vascularity; and “downstream” is away from the occlusion barrier to the remaining vascularity, i.e., systemic circulation, in communication with the site of hemorrhage.

Each of the various embodiments described herein is able to achieve more precise regulation of the degree of aortic occlusion and controlled incremental restoration of downstream reperfusion. Accordingly, one object of the various embodiments of the invention is to quickly staunch a source of bleeding. Another object is to reinitiate blood flow to deprived areas of the body while maintaining adequate flow and pressure in the vascularity serving the brain, lungs, and other critical organs.

A further object of the various embodiments of the invention is to allow a physician to safely transition a patient from a state of complete aortic occlusion to a plurality of levels of partial aortic flow and back and forth between complete occlusion and a plurality of levels of partial flow. The invention will allow a physician to wean a patient between various states of partial aortic flow to promote a more effective process for promptly responding to the patient's varying physiologic and vascular conditions.

Yet another object of the various embodiments of the invention is to allow a physician to wean a patient dynamically in real-time to respond to a patient's changing physiologic conditions. A further object of the various embodiments of the invention is to allow controlled distal reperfusion as required to minimize the likelihood of reperfusion injury associated with tissue ischemia associated with aortic occlusion. Another object of the various embodiments of the invention is to support patients suffering from other non-hemorrhagic causes of shock including, but not limited to, sepsis, cardiogenic shock, and spinal shock.

Not all of the objects described above need be accomplished in aggregate by any one or more of the various embodiments of the invention. Each of the objects may be accomplished individually or in combination with other objects by any one of the embodiments according to the invention. Consequently, interpretation of the claims herein should not be limited by any one or more of the objects addressed above.

Thus, in accordance with embodiments of the present invention, an endovascular variable aortic occlusion device is provided that comprises a central guide wire; a distal end potion that includes a first wire framework and an occlusion barrier; a delivery sheath, and a proximal end portion that includes a hand piece having a stationary portion and a movable portion. The first wire framework of the distal end portion is radially expandable and collapsible. The wire framework is configured to radially expand to a sufficient radial circumference to engage with an aortic wall within a lumen of an aorta to secure the device within the aorta. The occlusion barrier surrounds at least a portion of the first wire framework and is attached thereto to provide a cup-shaped occlusion barrier, such that an upper perimeter of the occlusion barrier contacts the aortic wall when the wire framework is radially expanded. The occlusion barrier also includes at least one adjustable passageway therein to facilitate controlled anterograde blood flow. The delivery sheath is extensible and retractable, wherein a collapsed form of the first wire framework is contained therein during delivery of the device into the lumen of the aorta. The movable portion of the hand piece controls a translational movement of the delivery sheath relative to the wire framework to enable unsheathing and radial expansion of the first wire framework. The movable portion of the hand piece may also be configured to adjust the at least one adjustable passageway to regulate controlled anterograde blood flow.

Each of the various embodiments described herein have common elements that support the delivery of an effective occlusion barrier, but each of the embodiments has slightly different movable elements for controlling the adjustable passageway to regulate controlled anterograde blood flow. As appropriate, additional detail associated with each of the described embodiments will focus on the specific movable structural elements that provide control of anterograde (or downstream) blood flow rather than the common elements. Following is a listing of the various embodiments of the invention described herein, named in reference to their movable structural elements that enable flow control: 1) Fenestrated cylindrical conduit (“FCC”); 2) Single aperture reduction (“SAR”); 3) Captive balloon (“CB”); 4) Fenestrated cone (“FC”); 5) Peripheral internal constriction (“PIC”); 6) Lasso aperture closure (“LAC”); 7) Rotating cup (“RC”); and 8) Deformable cup (“DC”).

In a first embodiment, identified herein as a Fenestrated Cylindrical Conduit (FCC), the EVACC comprises a catheter-based system having a proximal hand piece for controlled deployment and operation of a distal portion of the device, wherein the distal portion is used to both partially and completely occlude the aorta. The distal portion of the EVACC comprises the components necessary to create an occlusion barrier within a targeted blood vessel, e.g., the aorta. In this first embodiment, a cylindrical conduit having a plurality of orifices (i.e., a fenestrated cylindrical conduit) extends proximally from a bottom of the occlusion barrier. Regulation of anterograde blood flow is achieved by translational movement of the delivery sheath relative to the occlusion barrier to change a number of orifices in an uncovered state to adjust an available flow area for blood flow. In one aspect, the occlusion barrier may comprise an expandable and collapsible impermeable membrane that is supported by an expandable and collapsible egg-shaped memory wire architecture. When deployed to occlude a blood vessel, the memory wire architecture expands the impermeable membrane to form a cup-shaped occlusion barrier. The conduit and the occlusion barrier may be formed as a unitary body or may be discreet components joined together (e.g., by glue, thermal fusion, or a mechanical mating arrangement, for example).

The collapsible membrane and associated memory wire architecture are deployed into a vessel through a delivery sheath. During use, when deployed out the end of the delivery sheath, the memory wire architecture and an upper perimeter of the cup of the collapsible membrane expand to the size of the lumen of the blood vessel, e.g., the aorta, creating a barrier or restriction to flow. The cup-shaped occlusion barrier funnels flow into the cylindrical fenestrated conduit. The fenestrated conduit has a plurality of orifices or perforations that can be exposed or covered to support variable downstream flow to systemic circulation. Linear translation of the delivery sheath causes the orifices in the fenestrated conduit to be exposed or covered. Thus, the EVACC is able to control the rate of blood flow through the orifices or fenestrations below the occlusion barrier as well as the blood pressure on either side of the occlusion barrier. Once the occlusion barrier is fully deployed within the aorta, the delivery sheath may be retracted in a controlled and graded fashion to uncover one or more orifices in the fenestrated conduit, thereby allowing blood to flow from a higher-pressure upstream vascular region to a lower pressure downstream systemic vascular region.

In a second embodiment of the invention, identified herein as a Singled Aperture Reduction (SAR), the movable elements for controlling the adjustable passageway to regulate controlled anterograde blood flow is based on aperture reduction and/or enlargement via linear translation of the delivery sheath over a neck of the wire basket architecture. From its top perimeter, the cup of the occlusion barrier narrows to a single circular aperture whose size is variably adjusted by the advancement or retraction of the delivery sheath toward or away from the aperture. As the delivery sheath is moved towards the aperture, the wires of the supporting wire basket architecture are drawn close together to converge, and the diameter of the aperture is likewise reduced, restricting flow through the aperture, and reducing downstream systemic circulation. To increase flow, the delivery sheath is moved away from the aperture, enlarging the aperture and hence, the flow area.

In a third embodiment, identified herein as Captive Balloon (CB), the movable elements for controlling the adjustable passageway to regulate controlled anterograde blood flow include an inflatable obstructive member (e.g., a captive balloon) extending into a single circular orifice, where inflation or deflation of the inflatable obstructive member adjusts a diameter of the portion of the inflatable obstructive member extending into the orifice to change an available flow area for anterograde blood flow. In one aspect, the single orifice may extend into an impermeable cylindrical conduit, such that the captive balloon is within the conduit. Rather than tapering down to a fenestrated conduit, the impermeable cylindrical conduit is internally occupied by a corresponding cylindrical balloon. The cylindrical conduit may have limited expansion. The balloon may be inflated to varying degrees within the conduit to variably occlude the lumen of the conduit, thus increasing resistance to flow and flow restriction. Complete occlusion is accomplished by full inflation of the balloon within the cylindrical conduit.

In a fourth embodiment, identified herein as Fenestrated Cone (FC), the movable elements for controlling the adjustable passageway to regulate controlled anterograde blood flow include a conical conduit having a plurality of orifices (i.e., a fenestrated cone) extends proximally from a bottom of the occlusion barrier. Regulation of anterograde blood flow is achieved by translational movement of the delivery sheath relative to the occlusion barrier to change a number of orifices in an uncovered state to adjust an available flow area for blood flow. The proximal region of the cup of the occlusion barrier tapers to a conically-shaped fenestrated conduit, rather than the cylindrical fenestrated conduit described above. As with the first embodiment, retraction or deployment of the conical portion out of the sheath regulates flow by causing the fenestrations to be covered or exposed and the diameter of the conical portion to be reduced as the sheath is linearly translated to cover more of the conically-shaped conduit.

In a fifth embodiment, identified herein as Peripheral Internal Constriction (PIC), movable elements for controlling the adjustable passageway to regulate controlled anterograde blood flow include a conduit portion comprising an elastomeric wall that extends proximally from the occlusion barrier; and a wire mesh structure comprising a cylindrical, helically-wound braid that is surrounded by the elastomeric wall of the conduit portion. This configuration is akin to a “finger trap” design. The proximal region of the cup of the occlusion barrier tapers to this conduit portion, whose interior incorporates a wire mesh structure (e.g., a helically-wound braid) anchored to a central structural wire. The proximal portion of this conduit portion is open to allow downstream flow. The wire mesh structure or architecture may be constructed of a shape memory material, such that in its native state, the conduit portion is open. Retraction on the cylindrical conduit portion results in elongation and diameter reduction, but does not disrupt the upper perimeter of the occlusion barrier's apposition to the aortic wall. Instead, mechanical retraction of the conduit pulls against a point of fixation on a central structural wire. By elongating and narrowing the conduit portion, flow through the device is variably restricted.

In a sixth embodiment, identified herein as lasso aperture closure (LAC), the movable elements for controlling the adjustable passageway to regulate controlled anterograde blood flow include a lasso aperture constriction. The proximal region of the cup-shaped occlusion barrier narrows to an aperture or orifice that is variably restricted in diameter by the retraction of wires. In one embodiment, a lasso wire is provided that includes a distal end wire segment configured in a semi-circle having two end portions, and a wire portion extending from each end portion and terminating at the movable portion of the hand piece. The first wire framework passes through the semicircle of the distal end wire segment. An overlapping portion extending from the proximal terminal end of the occlusion barrier conforms to the distal end wire segment and thereby forms a single circular orifice at the proximal terminal end of the occlusion barrier. Retraction (or possibly rotation) of the wire portions extending from the end portions controls the size of the orifice. This function is similar to closing of a noose in a lasso.

In a seventh embodiment, identified herein as rotating cup (RC), movable elements for controlling the adjustable passageway to regulate controlled anterograde blood flow include two cup-shaped membranes where a first cup-shaped membrane has a first set of openings and a second cup-shaped membrane has a second set of openings. The adjustable passageway is formed by rotational alignment of the first and second set of openings to coincide, where at least one of the first or the second cup-shaped membrane is coupled to the movable portion of the hand piece. A rotational motion of the movable portion of the hand piece causes a relative rotation between the first and the second cup-shaped membrane to vary a degree of coincidence between the first and second set of openings. In one embodiment, the second (downstream) cup membrane includes a set of openings (e.g., two slots) to allow flow when the openings are uncovered, and is supported by the first wire framework. The first (upstream) cup membrane also includes a set of openings, and is supported by a second wire framework and may be rotated in either direction to cover or uncover the openings in the second cup membrane to restrict or increase blood flow, respectively.

In an eighth embodiment, identified herein as deformable cup (DC), the movable elements for controlling the adjustable passageway to regulate controlled anterograde blood flow include two mating cup-shaped membranes, where an inner cup is deformable. The occlusion barrier includes a first cup-shaped membrane bonded to the first wire framework, where interstitial openings are present around a perimeter of the first cup-shaped membrane; and a second cup-shaped membrane positioned upstream relative to the first cup-shaped membrane. The second cup-shaped membrane includes a central aperture in a bottom portion, and the second cup-shaped membrane conforms to a distal surface of the first cup-shaped membrane, and wherein the central aperture in the second cup and the interstitial openings in the first cup do not coincide when mated together. In one aspect, the two mating cups may be supported by a single wire basket architecture. The second cup-shaped membrane may include a flexible impermeable membrane having a central aperture. The aperture may be linearly reciprocated back and forth, creating various toroidal shapes and uncovering or covering the interstitial openings within the downstream cup. In a fully closed state, the second (upstream) cup-shaped membrane adapts to the shape of the first (downstream) cup-shaped membrane, such that the interstitial openings are fully covered by the upstream membrane and flow is occluded. Flow is increased by linear translation of a center wire to lift the center aperture, and a portion of the surrounding circumferential area, of the upstream membrane off the downstream occluding element, causing the interstitial openings between the petals of the first occluding element to be uncovered, thereby allowing flow to occur.

The accompanying drawings numbered herein are given by way of illustration only and are not intended to be limitative to any extent. Commonly used reference numbers identify the same or equivalent parts of the claimed invention throughout the accompanying drawings.

DETAILED DESCRIPTION

Following is a listing of the various embodiments of the endovascular variable aortic control catheter (hereinafter, “EVACC”) described herein, named in reference to movable elements used to control, regulate, and/or modulate anterograde blood flow and identified by their shortened acronym and associated reference numeral.

Turning now toFIGS. 1-3, an endovascular variable aortic control catheter (EVACC)10according to a first embodiment of the present invention is illustrated, wherein anterograde blood flow is controlled or regulated using a fenestrated neck50, hereinafter referred to as EVACC10.

The EVACC10comprises a longitudinal body31having a proximal end (not shown) and a distal end33, a supporting memory wire basket30, and an occlusion barrier40.

The wire basket30includes a plurality of ribs28that may be made of nitinol or other material having similar memory-shape properties. As illustrated, the wire basket30having a radially expanding distal end35, a medial expanded portion37, a radially collapsing proximal end39, and a proximally-extending neck32. The ribs28of the wire basket30are configured to be collapsible (seeFIG. 8A) and further configured to assume an approximately egg-shape when fully deployed and released from a delivery sheath60, as illustrated inFIGS. 1-3. It should be appreciated that other shapes, e.g., spherical or cylindrical, are further contemplated. The ribs28of the wire basket30expands when deployed out the end of the delivery sheath60and will collapse upon retraction back into the delivery sheath60. According to some embodiments, a nose cone25may be coupled to the distal end35of the wire basket30to provide smooth advancement of the EVACC10through the arterial tree during deployment. The nose cone25may be constructed of a radiopaque materials to allow tracking during use with appropriate medical imaging equipment.

The occlusion barrier40comprises a membrane, preferably made of expanded polytetrafluoroethylene (hereinafter, “ePTFE”). Other materials, such as polyester, may also be used to form the occlusion barrier40. The occlusion barrier40is configured to be collapsible (seeFIG. 8A) and further configured to expand to form a cup-like body42, as illustrated inFIGS. 1-3. The deployed occlusion barrier40includes a distal perimeter44, the cup-like body42extending from the distal perimeter edge44, and a proximally-positioned fenestrated neck50.

The fenestrated neck50includes a plurality of orifices or perforations52distributed along its length and is configured to such blood may flow therethrough when the orifices or perforations52not covered by the delivery sheath60. The fenestrated neck50is preferably made of ePTFE, but may be made of other materials to increase rigidity or elasticity during deployment. In one aspect, the occlusion barrier40comprising the cup-like body42and fenestrated neck50form one unitary piece. In another aspect, the occlusion barrier40may comprise a separate cup-like body42and fenestrated neck50, which are joined or bonded by various means, such as glue, thermal fusion or a mechanical mating arrangement.

FIG. 4is a perspective view of the view ofFIG. 3. As shown, the cup-like body42of the occlusion barrier40appears as being comprised of chords of membrane extending between ribs28of the wire basket10. In practice, the perimeter44and the cup-like body42will blossom to appose an inner arterial wall. The blossoming effect occurs as a result of the memory-shape properties of the ribs28of the wire basket10and pressure differential caused by blood flow, which causes the occlusion barrier40to expand in the manner similar to a wind sock.

FIG. 5is a top plan view of the EVACC10, emphasizing the view into the cup-like body42of the occlusion barrier40in a fully deployed state with the J-tip22, the conical tip25and the internal wire basket30.FIG. 6is a bottom plan view of the EVACC10, emphasizing a lengthwise view from the distal end of the EVACC10in a fully deployed state.

The EVACC10may be used with a guide wire20and the delivery sheath60. In that regard, the guide wire20may extend through a lengthwise central axis of the longitudinal body31, the wire basket30, and distally from the distal end33of the longitudinal body31. The delivery sheath60is configured to surround and be in slidable relation with the guide wire20, the wire basket30, and the occlusion barrier40.

Now, in greater detail,FIG. 2is an enlarged view of the EVACC10ofFIG. 1. The guide wire20is a self-centering rigid endovascular guide wire20used to reach a target occlusion location within a patient's vascular system. The endovascular guide wire20includes a J-tip22at a distal end34thereof. The J-tip22ensures that the distal components of the EVACC can be smoothly advanced or retracted within the arterial complex to reach a desired location for occlusion. The J-tip22provides centering of the guide wire20and the delivery sheath60within the lumen of the artery.

Turning now toFIG. 3, a side elevation view of the distal components of the EVACC10in an assembled and deployed state is shown. The ribs28of the wire basket30are fully deployed, expanding the occlusion barrier40to create the cup-like body. The neck32of the memory wire30is deployed beyond the end of the delivery sheath60to expand the fenestrated neck50and the proximal end54of the neck52and uncover the perforations52.

FIGS. 7-9provide illustrations of the EVACC10in use and operation. The description provided regarding use and operation of this first embodiment, the EVACC10, is applicable to the use and operation of the various additional embodiments described herein.

FIG. 7is a simplified illustration of a method used to deploy the EVACC10in a patient62. The central guidewire20and is inserted into an incision (not shown) in the femoral artery64and guided through the exterior iliac artery65, the common iliac artery66, the abdominal aorta67, the thoracic aorta68, and up to the aortic arch69or until reaching a targeted occlusion location (illustrated as being at about the thoracic aorta68). The delivery sheath60with the EVACC10may then be directed over a proximal end of the guide wire20, along the length of the guide wire20to the targeted occlusion location. The EVACC10is preferably inserted into the arterial tree through a 7-French sheath or smaller. According to some embodiments, delivery sheath60and EVACC10are preferably deployed through a percutaneous introducer catheter (not shown) directly into the femoral artery.

During initial insertion into the arterial tree and through advancement to the desired occlusion site within the thoracic aorta68, the central guide wire20, the wire basket30, the occlusion barrier40, and the fenestrated neck50are initially enclosed in the delivery sheath60, in a manner similar to vena cava filter deployment catheters. Once so positioned at the occlusion, the guide wire20and the EVACC10may remain stationary while the delivery sheath60is retracted, thereby deploying the wire basket30and the occlusion barrier40. With the wire basket30and occlusion barrier40unrestrained by the delivery sheath60, the wire basket30and occlusion barrier40assume natural, opened positions within the lumen of the thoracic aorta68such that the cup-like body42of the occlusion barrier and ribs28of the radially expanding distal end35of the wire basket30(and possibly of the medial expanded portion37and the radially collapsing proximal end39) appose the inner wall of the thoracic aorta68, thereby creating a sealing portion buttressed by the unfurling of the occlusion barrier40.

The degree to which the fenestrated neck50is opened to allow flow is controlled by a hand piece70connected to a proximal portion of the EVACC10(outside the patient62). An exemplary version of a hand piece70used to manipulate and control the distal components of the EVACC10is shown inFIG. 1. The hand piece70comprises a stationary distal grip71and a rotatable proximal grip72. Proximal grip72is rotatable on threaded guide74to manipulate the distal components of the EVACC during and after deployment. Additional wire assemblies (not shown) may be threaded through a center lumen (not shown) of the threaded guide74to provide additional methods for actuating the distal components.

The degree of occlusion and flow control may be manipulated by covering and exposing the perforations52of the fenestrated neck50via advancement and retraction of the delivery sheath60. The advancement and retraction of the delivery sheath60may be accomplished by rotary manipulation of the rotatable grip72of hand piece70to advance a threaded guide74in either a proximal or a distal direction. The stationary distal grip71and rotatable proximate grip72of the hand piece70are rotated in opposite directions to linearly translate the threaded guide74, which is attached via pull wires (not shown) to the sheath60and/or the fenestrated cylindrical conduit50.

The EVACC10and the additional embodiments described herein may be equipped with blood pressure measuring capabilities proximal and distal to the occlusion barrier40for measuring downstream and upstream blood pressure, respectively. The blood pressure measuring capabilities may comprise a manometer mounted on the EVACC10or a channel communicating with a transducer at the proximal end and a port at the distal end of the EVACC10. Blood pressure measuring may also be accomplished by use of a fiber optic in vivo pressure transducer as described in U.S. Pat. Nos. 5,392,117 and 5,202,939, each of which is incorporated herein by reference in its entirety, or a Radi PRESSUREWIRE as described in U.S. Pat. Nos. Re 35,648; 5,085,223; 4,712,566; 4,941,473; 4,744,863; 4,853,669; and 4,996,082, each of which is incorporated herein by reference in its entirety.

With the inclusion of upstream and downstream pressure sensors, upstream and downstream blood pressure measurements may then be recorded and displayed via a monitor at a proximal end of the EVACC10. A control device or module (not shown) may be programmed with various preferred treatment and operational parameters. The control device may then provide automated control of the operational parameters including: 1) blood pressure, upstream and downstream of the occlusion barrier40, and 2) flow diversion through the uncovered perforations52of the fenestrated neck50. For example, the control device can include a set pressure threshold to maintain upstream blood pressure to a desired level.

Data communicated to the pressure monitor from pressure sensors may be transferred or transmitted to the control device, which then sends control signals to a separate electrically-powered rotary unit to linearly translate the threaded guide74and the delivery sheath60. The translational movement of the delivery sheath60by the threaded guide74controls exposure of perforations52in the fenestrated cylindrical conduit50. The threaded guide74retracts or extends the delivery sheath60to uncover or cover the perforations52, thereby adjusting the diversion of flow from upstream to downstream and causing modification of blood pressure on each side of the occlusion barrier40.

In the field, where a separate automated control device may not be available, the hand piece70can be manually rotated to obtain desired upstream and downstream blood pressures. An audible alarm may be incorporated into the pressure monitor to sound when blood pressures exceeds desired thresholds. In one aspect, the rotary unit, pressure monitor, and control device may be integrated into the hand piece70of the EVACC10.

The EVACC10, and the additional embodiments described herein, are configurable to provide adaptive control of the means for flow regulation. Adaptive control is described in the context of the EVACC10, but is intended to extend to the functionality of the additional embodiments described herein. In each embodiment, adaptive control is accomplished via manipulation of the various movable elements used for anterograde blood flow control.

Hence, in the case of the EVACC10, adaptive control may be accomplished via the exposure or covering of the perforations52based on continuous dual pressure measurements both upstream and downstream of the occlusion barrier40. Estimates of systemic flow may be determined via algorithms correlated to each EVACC10based on the pressure measurements. The real-time availability of both flow measurements and pressure measurements may then be used to inform either physician decisions or automated adaptive control of the EVACC10according to specified operational parameters. For example, just as a tourniquet is periodically released to allow flow to avoid further tissue damage, the EVACC10may operate via the automated control device to periodically adjust flow downstream of the occlusion barrier40to avoid ischemia, or, to reduce downstream flow to divert flow to the brain and other vital organs upstream of the occlusion barrier40.

Turning now toFIGS. 8A through 8C, the deployment of the occlusion barrier40and wire basket30is shown. InFIG. 8A, the EVACC10has been positioned within the thoracic aorta68at a desired location. InFIG. 8B, the delivery sheath60has been retracted from over the wire basket30, allowing the ribs28of the wire basket30and the cup-like body42of the occlusion barrier40to expand slightly. InFIG. 8C, the entire wire basket30and occlusion barrier40have been deployed out the delivery sheath60within the thoracic aorta68and the fenestrated neck50has been exposed outside the delivery sheath60providing an initial level of flow wherein the occlusion barrier40is operating in a full open state.

Turning now toFIGS. 9Athough9C, the manipulation of flow using the EVACC10is illustrated. InFIG. 9A, the wire basket architecture30and occlusion barrier40are both collapsed within the lumen of the delivery sheath60while positioned at a desired occlusion location. Note that the various arrows indicate the general distribution of blood flow during each of the described states, where blood is indicated by the dotted markings.

InFIG. 9A, with the EVAC10positioned at a desired location, flow continues to the site of hemorrhage with no occlusion or regulation of flow. Now, inFIG. 9B, the wire basket architecture30and occlusion barrier40are fully deployed out the distal end of the delivery sheath60. In this configuration, the occlusion barrier40is deployed to appose the interior wall of the aorta A, but the fenestrated cylindrical conduit50is still fully covered by the delivery sheath60, thereby causing full occlusion of downstream blood flow, with all existing flow redirected to upstream portions of the vascular. Now, inFIG. 9C, the delivery sheath60has been retracted to expose a portion of the fenestrated cylindrical conduit50and the perforations52, providing an adjusted level of flow through the occlusion barrier40, through the fenestrated conduit50and out the perforations52and downstream to support systemic circulation. Note that partial occlusion may distribute blood flow to other upstream elements of the vascular, while still allowing downstream flow.

The delivery sheath60may be advanced or retracted over the fenestrated cylindrical conduit50to continually adjust flow from fully occluded to various levels of partial occlusion. This ability to continually redistribute flow as required by a patient's physiologic status allows a surgeon to maximize the probability of survival and minimize potential negative outcomes, such as hemodyamic collapse, when weaning the patient off full or partial occlusion.

Now, several alternative embodiments are described in detail in the following paragraphs. In each alternative embodiment, the device is deployed and used in a similar fashion as described for the EVACC10. However, in each alternative embodiment, the structure, configuration, and operation of movable elements used for flow control will differ to varying degrees.

Referring now toFIG. 10, a second embodiment of the EVACC100is illustrated. The EVACC100comprises an anterograde blood flow control based on a single aperture reduction and includes a wire basket130and an occlusion barrier140. The egg-shaped memory wire basket130supports a flexible cup-shaped occlusion barrier140having a perimeter144and a cup-shaped body142that narrows to a single aperture150having a maximum deployed diameter. The maximum deployed diameter of the single aperture150establishes the maximum flow rate through the occlusion barrier140. The diameter of the single aperture150is reduced by the advancement of a delivery sheath160towards the single aperture150, causing ribs132of the wire basket130to converge. As the ribs132converge, the diameter of the aperture150is reduced, thereby restricting flow through the aperture150. As the delivery sheath160is retracted, the ribs132diverge to a deployed, memory state and the single aperture150is enlarged, thereby allowing increased flow. The EVACC100is fully occluded when the delivery sheath160is advanced to cover and envelop the single aperture150.

Referring now toFIG. 11, an exploded view of the EVACC100with additional components are shown. The additional components may include a central guide wire120having J-tip122, a tapered nose cone125for receiving the distal end134of a wire basket130, and a delivery sheath160. The wire basket130converges to a distal end134, which is captured within a base of the tapered conical tip125.

FIG. 12is a perspective view of the EVACC100from the distal end to the proximal end. The ribs132extend through the single aperture150to deploy the occlusion barrier140via the wire basket130. The occlusion barrier140is extended by the ribs132of the wire basket130to establish the perimeter144of the occlusion barrier140.

FIG. 13is another perspective view of the EVACC100from the proximal end to the distal end. The aperture150is joined to the supporting wires133so that as the supporting wires133are retracted into the sheath160, the aperture150reduces in size. Once the supporting wires133have been fully retracted into the sheath160to up to the aperture150, the aperture150is closed and flow is fully occluded. As with other embodiments, the amount of flow may be adjusted by advancing or retracting the sheath160over the aperture150and supporting wires133from a fully occluded state to a partially occluded state, thereby causing the aperture150to vary in size. In other versions of the EVACC100, the aperture150may have a different size, which would modify the total flow through the aperture150in a fully deployed state.

Referring now toFIG. 14, an EVACC200according to a third embodiment of the invention is shown and includes an anterograde blood flow control employing a captive balloon concept.FIG. 14includes elements similar to those previously described in other embodiments including a central guide wire220, a J-tip222, a cone shaped tip225, a wire basket230, an occlusion barrier240, and a delivery sheath260. The wire basket230includes ribs233that extend proximally to form a throat232; the occlusion barrier240includes a cup-like body241, a distal perimeter244, and an occlusion barrier neck242extending proximally from the cup-like body241. The occlusion barrier neck242and extended throat232are sized to receive an inflatable balloon250. The extended occlusion barrier neck242is sized to expand less than the perimeter244of the occlusion barrier240. Consequently, the occlusion barrier neck242constrains expansion of the balloon250such that full expansion of the balloon250within the throat232and occlusion barrier neck242causes the lumen within the occlusion barrier neck242to be fully occluded by the balloon250. Flow may be adjusted by deflating or inflating the balloon250within the occlusion barrier neck242; this changes the available flow area.

Referring now toFIG. 15, individual components of the EVACC200with additional components are shown. Additional components include the endovascular guide wire220having J-tip222, a tapered nose cone225for receiving the distal end of the wire basket230, the extended throat232, the occlusion barrier240, the corresponding inflatable balloon250, and the delivery sheath260.

Referring now toFIG. 16, a perspective view from the distal end to proximal end of the EVACC200in a fully deployed state. The captive balloon250is fully inflated, creating full occlusion.

Likewise,FIG. 17is another perspective view of the EVACC200from the proximal end to the distal end of the extended occlusion barrier240. The balloon250extends into the cup-like body241of the extended occlusion barrier240. The balloon250resides within the throat232, which resides within the extended occlusion barrier neck252. Unlike other described embodiments, rather than adjusting flow by advancing and retracting the sheath260, flow is adjusted by inflating or deflating the balloon250. Hence, flow may be adjusted from a fully occluded state to a partially occluded state, and back.

Referring now toFIG. 18, an EVACC300according to a fourth EVACC embodiment having anterograde blood flow controlled or regulated using a fenestrated cone concept hereinafter the EVACC300is shown. The EVACC300is substantially similar to the previously described EVACC10(FIG. 1) with the exception of the occlusion barrier340, which tapers down to a conically-shaped fenestrated conduit350, rather than a fenestrated neck50. As with the EVACC10(FIG. 1), advancing or retracting of the conically-shaped fenestrated conduit350with respect to the delivery sheath360regulates flow by causing perforations352to be covered or exposed and the diameter of the conically-shaped portion of the fenestrated conduit350to be enlarged or reduced as retracted into the delivery sheath360.

FIG. 19is a component view of the EVACC300, comprising an endovascular wire320having a J-tip322, a tapered nose cone325for receiving the distal end334of a wire basket330, an occlusion barrier340having a conically-shaped fenestrated conduit350with perforations352, and a delivery sheath360. The occlusion barrier340comprises a cup-shaped body342having an upstream perimeter344. The wire basket330includes a throat assembly332, which expands to deploy the fenestrated conduit350. The fenestrated conduit350includes a downstream end orifice354.

Referring now toFIG. 20, a perspective view from the distal end to the proximal end of the occlusion barrier340of the EVACC300is illustrated revealing the perforations352.

InFIG. 21, a perspective view from the proximal end to the distal end illustrates the conically-shaped fenestrated conduit350and associated perforations352. Flow is adjustable from a fully occluded state to a partially occluded state by advancing or retracting the delivery sheath360over the conically shaped fenestrated conduit350.

Referring now toFIG. 22, a side elevation view of an EVACC400according to a fifth embodiment of the invention is shown, where anterograde blood flow is controlled or regulated using a peripheral internal constriction (PIC)450. As shown, a central guide wire420is configured to move the EVACC400through the vascular to a targeted location. A distal tapered nose cone425is slidably received onto the central guide wire420. At its base, the nose cone425is sized to receive a distal end434of the wire basket430, where each support wire431converges to form a tip at the distal end434. The wire basket430is partially enveloped by an occlusion barrier440made of appropriate collapsible and expandable material, such as ePTFE, polyester or other material having similar characteristics. Upon deployment within an artery, the wire basket430and the occlusion barrier440expand to create a cup-shaped body442. The cup-shaped body442expands to appose the inner arterial wall. The occlusion barrier440includes an upper perimeter444and an extended neck446. The PIC450, which is a wire mesh451comprising a cylindrical, helically-wound braid, is positioned within the lumen of the extended neck446and the extended neck446and PIC450are joined to each other. The extended neck446includes a downstream orifice454that is deployed out the end of the delivery sheath460to allow flow when the occlusion barrier440is deployed and the extended neck446open.

Referring now toFIG. 23, the individual components of the EVACC400are illustrated and described in greater detail. The notable difference includes the PIC450and the extended neck446of the occlusion barrier440. In use, the PIC450is lengthened to reduce an inner diameter or shortened to increase the inner diameter. In one aspect, the extended neck446may be constructed of ePTFE, polyester, or other appropriate material having sufficient elasticity to accommodate the manipulation of the PIC450from a closed state to an open state.

Referring now toFIG. 24, a perspective view from the distal end to the proximal end of occlusion barrier440of the EVACC400is provided. The PIC450is deployed within the lumen of the extended neck446of the occlusion barrier440. The wire basket430expands to deploy the occlusion barrier440, creating the cup-like body442and extended neck446. The perimeter444of the occlusion barrier440apposes and conforms to the shape of the interior of the blood vessel, thereby funneling flow into the extended neck446and through the proximal orifice454. The distal end434of the wire basket430is captured within the conical tip425.

Turning now toFIG. 25, a perspective view from the proximal end to the distal end of the EVACC400in a fully deployed state is provided. Flow control is achieved by the PIC450in conjunction with the extended neck446and the occlusion barrier orifice454.

In a fully deployed state, the EVACC400is actuated by the retraction or extension of an inner pull wire456that causes the PIC450to dilate or contract its diameter. The diameter of the proximal orifice454will increase or decrease in size as well, in correlation to the lengthening or shortening of the PIC450. The individual wires431of the PIC430are threaded together, wherein extending the PIC430causes individual wires431to rotate and mesh more closely together, thereby increasing resistance to flow caused by the restriction within the extended neck446. Thus, upstream and downstream blood pressure and flow through the EVACC400may be adjusted and controlled. The material used to form the extended neck446will have sufficient elasticity to stretch and narrow in correlation with the PIC450.

Referring now toFIG. 26, in an EVACC500according to a sixth embodiment of the invention having anterograde blood flow controlled or regulated using a lasso wire550is shown. A wire basket530narrows to a throat532that may be variably occluded by the retraction of wires550configured to narrow the aperture554when tension is placed on the lasso wires550. The EVACC further includes a central guide wire520having a J-tip522for guiding the EVACC500to a target location within a patient's vasculature. A distal end534of the wire basket530is captured within a tapered cone525. The wire basket530, which may be constructed using shape memory materials, is enveloped by and bonded to an occlusion barrier540forming an expandable and collapsible cup-like body542. The occlusion barrier540may be made of ePTFE, polyester or other similar material. The cup-like body542, when deployed, includes a perimeter544, which will appose the interior wall of the blood vessel, and a proximal orifice554through which flow will be diverted when in an open state. A lasso wire550is slidably joined with the proximal orifice554. Manipulation of the lasso wire550causes the proximal orifice554to either increase or decrease in diameter, thereby regulating flow through the proximal orifice554and establishing a pressure differential across the proximal orifice554. The occlusion barrier540and wire basket530is delivered to a specific location in the vascular by the delivery sheath560.

Referring now toFIG. 27, an enlarged exploded front elevation view of the individual distal components of the EVACC500is provided. The EVACC500comprises an endovascular guide wire520having a J-tip522, a tapered nose cone525for receiving a distal end534of the wire basket530, a lasso wire550, an occlusion barrier540deployed to form a cup-like body542having a perimeter544and a downstream orifice554. A delivery sheath560facilitates the ease of advancing the occlusion barrier540to a targeted location.

Referring now toFIG. 28, a perspective view from the distal end to the proximal end into the interior of the cup542of the EVACC500is provided. A lasso wire550extends to and is slidably bonded within a rim552of the proximal aperture554. The throat532of the EVACC500blossoms through the aperture554and continues to form the wire basket530.

Referring now toFIG. 29A, a perspective view from the proximal end to the distal end of the EVACC500emphasizes the proximal aperture554of the occlusion barrier540in a fully deployed state, extended out of the delivery sheath560.

Referring now toFIG. 29B, an enlarged view of the occlusion barrier540of the EVACC500in a fully deployed state is shown in greater detail. The cup-like body542includes an aperture554at a downstream end. The throat532expands to fully deploy and open the proximal aperture554to allow flow. The lasso wires550extended into the aperture554such that retraction of the wires550cause the aperture554to be cinched down to a smaller size, thereby reducing flow through the proximal aperture554.

Referring now toFIG. 30, in an EVACC600according to a sixth alternative embodiment of the invention, where anterograde blood flow is controlled or regulated using a rotating mated cups concept. The EVACC600comprises two mating cup-shaped membranes640,650supported by a dual wire basket630,652. The first membrane640is supported by and bonded to first wire basket630. The second membrane640includes a first set of openings643(e.g., two slots) that serve as passageways to allow blood flow when uncovered. The second membrane650is supported by and bonded to a separate (second) wire basket652. The first membrane650, which includes a second set of openings653(e.g., two slots), is rotatable to cover the first set of slots643to varying degrees so as to increase or restrict blood flow downstream of the occlusion barrier640. When the first and second sets of openings643,653coincide flow through the occlusion barrier640occurs.

Referring now toFIG. 32A, an enlarged perspective view from the proximal end of the distal end of the EVACC600fully deployed out the delivery sheath660illustrates the arrangement of the first wire basket630enveloping the first membrane640. In this state, the first set of openings643are covered by the second membrane650.FIG. 32Bis the same view but with the second membrane650having been rotated such that the first set of openings643are uncovered to allow anterograde flow through the first set of openings643and to the downstream vasculature.FIG. 33Ais equivalent toFIG. 32Ain a closed state, but a perspective view from the distal end to the proximal end;FIG. 33Bis equivalent toFIG. 32Bin an open state but a perspective view from the distal end to the proximal end.

Referring now toFIG. 34AandFIG. 34B, a top plan view of the EVACC600emphasizes the mating of the first and second sets of openings643,653of the first and second membranes640,650, respectively, and illustrates the J-tip622.FIG. 34Ashows the EVACC600in a fully closed state, whereby the flow is fully restricted.FIG. 34Bshows the EVACC600in an open state, whereby the second membrane650is in a rotated position such that the first set of openings643of the first membrane640are fully uncovered, allowing maximum blood flow.

Referring now toFIG. 35AandFIG. 35B, a bottom plan view of the EVACC600is provided.FIG. 35Ashows the EVACC600in a fully closed state. The first set of openings643of the first membrane640are aligned such that flow is blocked by the second membrane650.FIG. 35Bshows the EVACC600in a fully open state, where the first set of openings643are uncovered from the second membrane650such that fluid may pass unrestricted through the EVACC600.

Referring now toFIG. 36A, an EVACC700according to a seventh alternative embodiment of the invention is shown where anterograde blood flow is controlled or regulated using a deformable mating cups concept. The EVACC700comprises two occluding barriers (e.g., cup-shaped membranes)740,750supported by a wire basket730. The first occluding barrier740is positioned downstream of (proximally to) the second occluding barrier750. The first occluding barrier740has multiple interstitial openings743around its perimeter. The second occluding barrier750, which is positioned upstream of the first occluding barrier740, comprises a flexible membrane that adapts to the shape of the wire basket730, and thus, the shape of the first occluding barrier740. In a closed state, the interstitial openings743of the first occluding barrier740are covered by the second occluding barrier750and anterograde blood flow through the EVACC700is minimized or stopped.

Referring now toFIG. 36B, flow is increased by linear translation of a guide wire720to lift a center wire portion726of the second occluding barrier750off the first occluding barrier740, causing the interstitial openings743of the first occluding barrier740to be uncovered.FIG. 36Bshows the EVACC700in an open state with interstitial openings743uncovered. The EVACC700includes a central aperture752that acts as a choke or restriction on flow. The aperture752size may be varied to change the amount of flow. However, the size of the aperture752correlates with the size of a bottom center portion of the first occluding barrier740such that flow may be effectively stopped when the second occluding barrier750is laid flush against the interior of the first occluding barrier740.

Referring now toFIG. 37, a semi-exploded view of components of the EVACC700is shown. Central guide wire720having J-tip722allows the EVACC700to be carefully deployed through a patient's vascular to reach a desired occlusion location. Tapered cone725is slidably received on the central guide wire720and likewise is sized to receive the distal tip734of the wire basket730. The second occluding barrier750having a center wire structure726and orifice727is slidably received on the central guide wire720. The first occluding barrier740is likewise slidably received on the central guide wire720to mate with the second occluding barrier750. Both the first occluding barrier740and the second occluding barrier750are disposed within the interior of the wire basket730. The assembly is delivered to a desired location for occlusion via the delivery sheath760.

Referring now toFIG. 38AandFIG. 38B, a top plan view of the EVACC700is provided.FIG. 38Ashows the EVACC700in a closed state, with interstitial openings743covered such that flow is restricted.FIG. 38Bshows the EVACC700in an open state, with the second occluding barrier750lifted at its center such that the aperture752rises off the first occluding barrier740. As a result, the interstitial openings743are uncovered, allowing blood flow to pass through the aperture752and through the interstitial openings743to the remainder of the downstream vascular network.

Referring now toFIG. 39AandFIG. 39B, a bottom plan view of the EVACC700is provided.FIG. 39Ashows the EVACC700in a fully closed state. The interstitial openings743of the first occluding barrier740aligned with the second occluding barrier740such that flow is blocked by the second occluding barrier750.FIG. 39Bshows the device700in a fully open state, whereby the interstitial openings743are uncovered such that blood flow may occur, constrained by the size of the orifice752.

Referring now toFIG. 40A, a cross-sectional view of the EVACC700inFIG. 38Ataken along section line3-3is shown.FIG. 40Ashows the EVACC700in a fully closed state, in which fluid flow is blocked. Referring now toFIG. 40B, a cross-sectional view of the EVACC700inFIG. 38Btaken along section line4-4is shown.FIG. 40Bshows the EVACC700in an open state. The wire portion726of the second occluding barrier750is in a lifted position, causing the interstitial openings743between the petals745of the first occluding barrier740to be uncovered and allowing blood to flow through the aperture752and the interstitial openings743to the remainder of the vascular.

Referring now toFIG. 41A, an enlarged perspective view of the interior of the EVACC700in a fully closed state is shown.FIG. 41Bis the same perspective view but with the second occluding barrier750raised to allow flow.FIG. 42AandFIG. 42Bcorrespond toFIGS. 41A and 41B, but from the proximal end to distal end perspective view.

Although not specifically shown, applicable to several embodiments described herein, the EVACC may include one or more pressure sensors that communicate blood pressure measurements to an external display, an external control device, or both. The display provides pressure readings to the surgeon to inform the surgeon's operational decisions. Alternatively, the pressure data may be processed by the external control device, and then used by the control device to determine a desired level of flow restriction. For example, the control device can operate a rotary unit, such as a small stepper motor, to operate the central threaded guide, which may be configured to a) linearly translate the sheath back and forth over perforations in a fenestrated conduit, b) linearly translate a tension wire to constrict or expand a lasso, or c) pressurize or depressurize a captive balloon, for example. Additionally, the EVACC may also incorporate and provide automated control of the degree of flow restriction via an active control algorithm that determines adjustments based on the patient's physiologic status as determined by blood pressure, other relevant metrics, and the assessment of the surgeon. A visual display and associated operational dashboard provides an active touch interface for use by the surgeon or a surgeon's assistant to actively control the operation of the EVACC once deployed. Where an automated control system is provided, the display provides relevant operational parameters and allows automated control to be overridden by the surgeon or assistant. The display may include icons that are selectable by touch, keyboard, mouse, voice, or gesture. The interactive features will allow the surgeon or assistant to quickly select various desired flow and pressure conditions to achieve certain physiologic objectives and set desired operating parameters.

Although driven by a need to address treatment of soldiers injured on the battlefield, the EVACC, in its several embodiments described herein, has applicability that extends beyond military and civilian trauma victims. Any patient with significant risk of hemorrhage will benefit from use of the EVACC to support regulation of distal aortic flow to augment vital perfusion to critical organs. In addition, patients that require increased diversion of blood flow to other portions of their body, such as the brain, can use the device, initially deployed to allow full flow, to gradually restrict downstream flow, and increase flow and pressure to those targeted areas. This approach for augmenting central aortic pressure to perfuse the heart, lungs and brain would extend beyond hemorrhagic shock to include any patient with hypotension and shock that needed augmentation of pressure to keep vital organs alive while other therapeutic measures were undertaken or to support physiology during transport to definitive care.

In addition, although shown and described herein as applicable to use in human subjects, the EVACC is likewise adaptable to use in animal subjects.

The present invention has been particularly shown and described with respect to certain preferred embodiments and features thereof. However, it should be readily apparent to those of ordinary skill in the art that various changes and modifications in form and detail may be made without departing from the spirit and scope of the inventions as set forth herein and the appended claims.