Micro-macro endovascular occlusion device and method

Abstract

The vascular plug includes an upper structure that can expand from a collapsed percutaneous insertion configuration to an expanded deployed or use configuration. The upper structure includes a primary and secondary three-dimensional shape that allows occlusion of a wide range of vessel sizes from small to large through a small, out of proportion, delivery catheter. The plug includes shape memory elements for creating the radial force and the larger secondary three-dimensional twist or helical shaped upper structure required to create the target vessel occlusion.

Description

TECHNICAL FIELD

[0001] The present disclosure relates generally to devices and methods for occluding arterial and venous vessels under a variety of pathological conditions. BACKGROUND

[0002] There are many endovascular devices for occluding blood flow, including coils, detachable balloons, and most recently expandable mechanical occlusion devices, with or without a blood flow impermeable covering. Coils can be covered with fibers or coated with materials such as hydrogels to enhance clot formation. Despite these features, often many coils are required to occlude blood flow, increasing procedural time and potential cost. Coils can also be unreliable in their geometry and vessel space-filling properties after deployment. Furthermore, coils and / or clots can easily migrate distally in high flow conditions such as arteriovenous fistulas in the lung or elsewhere in the body. Vessels occluded by coils can re-open or recanalize, as reported in pulmonary arteriovenous fistulas. Detachable balloons can be difficult to thread through vessels and can prematurely detach. Premature detachment of balloons can lead to migration and occlusion of normal vessels, leading to complications. Balloons can shrink over time, leading to recurrence of the treated vessel pathology, as reported in carotid cavernous fistulas. Detachable, uncovered and membrane-covered expandable mechanical occlusion devices have been recently developed in an attempt to occlude blood flow faster, more durably and with greater spatial precision; commonly referred to as vascular plugs. These include the uncovered detachable Amplatzer vascular plug, made of a self-expanding nitinol mesh, delivered through different sized catheters or sheaths, causing vessel thrombosis. This device can not immediately cause thrombosis, especially for patients with coagulopathy requiring the use of more than one device. This device can be difficult to deliver and precisely deploy. Furthermore, this device can not provide long-term occlusion, especially in pulmonary arteriovenous fistulas where this has been reported. In early studies, covered devices such as the MVP micro-plug can provide immediate occlusion and good long-term occlusion. The MVP is the only covered plug that can be delivered through a microcatheter, which is particularly advantageous when navigating through tortuous anatomy and smaller vessels. The largest MVP microcatheter deliverable covered plug can only treat vessels up to 5 mm in diameter, which is a significant disadvantage. Larger MVP covered plugs require delivery through 4 or 5F (French) catheters depending on the target vessel size; these larger catheters are often too large and stiff to easily thread through the desired vasculature. Using these larger 4 and 5F catheters to target more distal vasculature can lead to technical failures, vasospasm, and vessel injury. With the MVP device, vessels up to 7 mm can be treated through a 4F catheter, and vessels up to 9 mm can be treated through a 5F catheter. Considering its small footprint and vessel anchoring ability, this device can not be suitable for high flow situations where migration can occur. Precise measurement or sizing relative to the target vessel is important. The relatively small length of the rigid nitinol frame is best suited for straight vessel segments or horizontal deployment areas.

[0003] It is desirable to occlude vessels larger than 5 mm with a covered plug through a microcatheter, which is not possible with currently available devices such as the MVP. Microcatheters are typically manufactured with two different inner diameters, 0.021 inch (standard) and 0.027 inch (high flow). Larger 4F and 5F diagnostic catheters typically have inner diameters of 0.040 inch and 0.046 inch, respectively. A 5F diagnostic angiographic catheter is typically used for proximal insertion of the catheter at the origin or proximal to large branch vessels of origin in the neck, chest, abdomen, pelvis, and lower extremities; and can fit both standard and high flow microcatheters. These larger 5F diagnostic catheters are typically difficult to advance further into primary or secondary aortic branch vessels such as the hepatic, splenic, renal, internal carotid, and inferior epigastric arteries, among others. It would be clinically advantageous to be able to occlude vessels larger than 5 mm with a covered vessel plug delivered through a 5F angiographic catheter. The target vessels for occlusion are typically larger than 5 mm, and thus cannot be occluded using microcatheter delivery of a vessel plug with current means and methods. In addition, microcatheters are advantageous for navigating through tortuous anatomy, which is typically difficult or impossible with larger 5F catheters. Venous embolization often requires occlusion of vessels with larger diameters than arteries, often requiring larger guide catheters or sheaths for device delivery, such as the uncovered Amplatzer plug.

[0004] In many cases, it is preferable to occlude the vessel on both the upstream and downstream sides relative to a given arterial or venous vascular lesion, i.e., to mechanically occlude the vessel segment. This can be difficult and / or cumbersome to achieve using currently available devices. For example, it can be desirable to occlude a fusiform aneurysm or abnormal dilation of a vessel on both sides, as the aneurysm can still fill or remain open after occlusion upstream of the artery alone. A fusiform aneurysm is spindle- or football-shaped; it bulges or dilates on all sides of the vessel. After occlusion upstream by a vessel plug, blood flow can backfill through collateral vessels downstream of the artery relative to the fusiform aneurysm, thereby maintaining the aneurysm open. Initial occlusion downstream of the vessel relative to the fusiform aneurysm can result in increased flow and pressure in the aneurysm, leading to rupture. In these cases, it is often safer to occlude distally only under conditions of proximal flow and pressure control (flow stasis) to prevent possible vessel rupture.

[0005] It is often desirable to primarily occlude saccular intracranial or peripheral saccular aneurysms while protecting the parent vessel from which they originate. Saccular aneurysms are blind end vascular outpouchings or sacs that occur from only one side of the vessel. Occlusion or closure of saccular aneurysms is typically achieved by placing multiple coils of different shapes and sizes directly within the aneurysmal sac. In using current methods, while effective, this procedure can be cumbersome, particularly for larger aneurysms, requiring multiple coils to fill the aneurysmal sac. Additionally, coils can compact as the aneurysm recanalizes, which often occurs at the aneurysmal neck or at the junction with the parent vessel. Coils can also prolapse into the parent vessel if the aneurysmal neck is wide. It has been shown that flow disruption within the blind aneurysmal sac leading to thrombosis can be achieved even with uncovered porous or mesh aneurysmal intrasaccular space filling devices, commonly referred to as flow disruptors. It is desirable for an aneurysmal intrasaccular space filling occlusion device that can approximate the typical spheroid or ellipsoid shape of a saccular aneurysm with a single or limited number of devices in order to more rapidly, effectively and possibly more permanently occlude the aneurysmal sac. SUMMARY

[0006] The present invention aims to provide an improved vascular occlusion device and / or related surgical method that solves the above-mentioned problems. In particular, the present invention contemplates an improved vascular occlusion device and / or related surgical method that enables the deployment of a vascular plug through a microcatheter that can assume a larger shape, occluding small, medium or large vessels with the same device delivered through a microcatheter. This is not possible with current devices.

[0007] The present invention also aims to provide an improved vascular occlusion device and / or related surgical method that allows the occlusion of vessels smaller and larger than 5 mm, which is the current upper limit of a microcatheter deliverable plug. Preferably, the same design can be used for 4 and 5F deliverable devices to occlude even larger arteries, veins, aneurysms or varicoceles.

[0008] The present invention further contemplates an improved vascular occlusion device and / or related surgical method in which the occlusive vascular plug allows a very large space filling capacity proportional to the diameter of the delivery catheter, facilitating large vessel or large aneurysm occlusion, which is not possible with current devices.

[0009] The present invention also relates to an improved vascular occlusion device and / or related surgical method in which the vascular thrombosis occurs gradually over a period of time, preventing the device from moving in high flow situations, giving the operator time to create a stable intravascular construct.

[0010] The present invention also seeks to provide improved vascular occlusion devices and / or related surgical methods that enable the deployment or installation of one or more vascular occlusion devices or plugs across a given segmental vascular lesion, such as a fusiform aneurysm, in a patient's vascular system, while occluding both downstream and upstream relative to a given vascular pathology.

[0011] The present invention includes improved vascular occlusion devices and / or related surgical methods that allow for the primary treatment of saccular intracranial or peripheral aneurysms.

[0012] The present invention includes improved vascular occlusion devices and / or related surgical methods in which the cumulative radial force exerted by the primary and secondary device structures is improved over currently available microcatheter deliverable vascular plugs.

[0013] The present invention seeks to provide improved vascular occlusion devices and / or related surgical methods in which the devices are easily deployed and configured in tortuous vascular segments.

[0014] More particularly, the present invention seeks to provide space-filling devices and / or related surgical methods for occluding pathological non-vascular spaces, such as those associated with the intestines, bile ducts or ureters.

[0015] The present invention generally contemplates improved vascular occlusion devices and / or related minimally invasive surgical methods.

[0016] The present invention relates to a collapsible tubular structure that self-expands to assume a tubular form and further self-configures to assume a larger secondary spiraling superstructure. This occlusive medical device is intended to address the problems of occluding large arteries and veins through a microcatheter. Coiled or helical shape memory elements are incorporated in an otherwise flexible and conformable tubular plug body to form the plug body into a large space-filling secondary helical or twisted shape. Depending on the size of the target vessel, two consecutively placed parallel or interlocking devices can be required for complete vascular occlusion, such as forming a double helix configuration. Using a 4 and 5F catheter deliverable vascular plug, the same device can be used to occlude even larger vessels at the expense of lower passability and larger external delivery catheter diameter. The secondary plug configuration is essentially a hybrid plug-coil design, resulting in a helical three-dimensional tubular helical superstructure.

[0017] The tubular structure or plug body is typically provided with an external covering or membrane, which can be impermeable or partially permeable. The partially permeable membrane provides gradual occlusion as the perforations in the membrane are blocked and closed by thrombus at a rate dependent on the pore size.

[0018] In another form of the self-expanding occlusive medical device according to the present application, the plug body is uncovered, optionally coated with various thrombogenic materials, such as fibrils or hydrogels, to induce thrombosis by the three-dimensional helical superstructure or stent after deployment.

[0019] The tubular structure is made of shape memory wires of a self-expanding network, wherein the wires selectively slide relative to one another. Such self-expanding or mechanically expanded by a balloon cage or lattice structure is well known in the field of blood vessels.

[0020] The vascular plug or medical occlusive device according to the present application comprises a superstructure that can expand from a collapsed insertion configuration to an expanded deployed or use configuration. The insertion configuration is small enough to be introduced percutaneously into the vascular system of a patient. The expanded deployed or use configuration is large enough to extend across a target blood vessel and engage the endothelial surface of such blood vessel. The superstructure is advanced by a microcatheter or larger catheter attached to a deployment wire. The occlusive device has a primary and secondary shape. The primary shape is a tubular covered or uncovered plug with a lattice-like outer wall made of strands or wires of spring-loaded or shape memory material, such as Nitinol or other metal alloys. The secondary shape is a three-dimensional helical or spiral-like configuration of the primary tubular shape resulting from additional internal shape memory elements or wires incorporated into the otherwise flexible and conformable plug body. The additional shape memory elements of the wires have a coiled base (unstressed) configuration and exert a strong enough shape memory force to twist the tubular structure or plug into a helical or spiral-like configuration. The tubular structure or plug can be attached to the end of a steering tether or wire and released from it after forming the primary and optionally secondary shape by a mechanical detachment mechanism or other means according to the target blood vessel size.

[0021] The vascular occlusive device according to the present application can be covered with an impermeable membrane, uncovered or alternatively coated with various thrombogenic materials, such as fibrils or hydrogels, to induce thrombosis by the three-dimensional helical superstructure or stent after deployment. The porosity of the uncovered plug wall or plug body can be selected to promote thrombosis; the weave pattern or design of the stent body can be varied to reduce the porosity of the plug wall, thereby increasing its throbogenicity. For a low porosity device, flow through it is minimal; a zero porosity device is impermeable to flow. A plug wall with possibly the lowest porosity while still maintaining the desired primary and secondary plug properties and shape is desirable. An uncovered low porosity plug can have a lower overall profile relative to even a thin covered plug.

[0022] The porosity of the wall of the vascular plug or medical occlusion device according to the present application can be adjusted according to different clinical and pathological conditions. A plug with very low porosity will thrombose more easily than a plug with higher porosity, while a plug with high porosity will be less prone to migration than a plug with low porosity under high flow conditions, allowing the operator to use one or more uncovered higher porosity plugs to create an initial stable construct or stent, followed by the placement of one or more covered or very low porosity devices to complete the occlusion of the vessel.

[0023] The intraplug porosity of a given occlusion device or plug can also vary from the upstream portion of the plug to the downstream portion. The upstream portion of the plug can have low porosity to promote stasis and thrombosis, while the downstream portion can have higher porosity to allow blood to flow into and out of the lumen of the plug, facilitating the repositioning or removal of the device prior to final plug deployment. A partially porous covering plug membrane can be placed at the downstream end of the plug to achieve similar results: transient limited flow through the plug body to reduce the opportunity for migration upon subsequent thrombosis.

[0024] An uncovered plug can be coated with an expanding hydrogel material that will activate upon contact with blood after deployment, thereby reducing the porosity of the plug wall over time, causing thrombosis within the plug and the target vessel. A hydrogel-coated plug can be useful in high flow environments, allowing time for the deployment of two stable interlocking plug devices before the assembled construct becomes impermeable to flow. The two plugs or occlusion devices can be inserted simultaneously through two delivery catheters that pass through a single larger guide catheter, or consecutively through one catheter, thereby reducing the opportunity for device migration. In other words, the use of a hydrogel coating will allow the creation of an occlusive plug that will reduce its porosity over time after initial deployment, which can be useful for more easily treating high flow pathologies.

[0025] Mechanical plug compaction after initial deployment can be used to reduce the porosity of an uncovered plug by compressing the braided pattern in the plug wall, thereby reducing the plug wall porosity.

[0026] The present invention provides membrane covered or uncovered vascular occlusion devices that can be delivered to a target site through a microcatheter or even a 4 or 5F catheter and are capable of occluding or filling a larger volume of a blood vessel than is currently possible. The occlusion devices according to the present invention have great clinical benefit for treating a variety of vascular pathologies including but not limited to bleeding blood vessels, aneurysms, varices and venous malformations. Even greater spatial filling capacity can be achieved by assembling the device in situ by interweaving or interlocking two or more consecutively deployed endovascular subunits. Thus, a first deployed occlusion device according to the present invention can assume a helical tubular configuration with a central passage when deployed in a large blood vessel or space, which passage is occluded by inserting and expanding a second occlusion device therein, which second occlusion device preferably has the same or similar helical tubular configuration. This variation of the present invention is useful for occluding large blood vessels, aneurysms or pathologic vascular spaces (e.g. the left atrial appendage) in the context of atrial fibrillation relative to current methods.

[0027] Thus, the present invention contemplates forming an occlusion assembly in situ from a plurality of individual occlusion devices or plugs. More specifically, the method entails assembling or interweaving two or more consecutively deployed devices or endovascular subunits. At least a first of the deployed devices or endovascular subunits has a helical tubular configuration upon expansion from a collapsed insertion configuration. This first deployed device or endovascular subunit expands to engage the endothelium of a target blood vessel or organ. Where the expanded first deployed device or endovascular subunit has a passage or access, at least one second deployed device or endovascular subunit is inserted into the passage or access in at least partially collapsed form and expands to fill and occlude the passage or access. The second deployed device or endovascular subunit can become interlocked with the first deployed device or endovascular subunit, possibly becoming lodged in the helical grooves or interturn gaps or clefts of the first deployed device or endovascular subunit. At times, it can be beneficial or necessary to use a third deployed device or endovascular subunit, which is inserted into a cavity or recess that can be present in the assembly of the first and second deployed devices or endovascular subunits.

[0028] To treat segmental vascular lesions, particularly long segment vascular disease, such as long, fusiform aneurysms, the present invention contemplates an elongated microcatheter deliverable vascular plug or occlusion device that can be expanded to varying degrees to completely span segmental vascular lesions in small and large vessels. This approach almost simultaneously occludes both the downstream and upstream portions of a fusiform aneurysm, minimizing the risk of hemodynamic changes and aneurysm rupture during plug deployment, and also prevents retrograde remodeling of the downstream aneurysm secondary to flow reversal. A safer treatment of segmental vascular lesion issues, particularly for long segment vascular disease (such as long, fusiform aneurysms), is an improved solution that places a continuous device (intravascular capture) in a strategic manner, two such devices are deployed through the same catheter to simultaneously occlude both the proximal and distal ends of the lesion (e.g., a fusiform aneurysm). The first proximal occlusion device is placed to reduce inflow to the lesion, and has a channel or bore (e.g., a doughnut hole of a helical plug configuration) designed to be traversed by the same delivery catheter for placement of one or more downstream occlusion devices relative to the vascular lesion. The catheter is then withdrawn and repositioned to place a second proximal device to close the proximal plug bore. Alternatively, one or more distal occlusion devices and then one or more proximal occlusion devices can be delivered through a microcatheter placed through a 5F inflatable balloon catheter at the proximal end of the vascular lesion to eliminate or reduce blood flow and intravascular pressure (flow stasis). Thus, a microcatheter deliverable occlusion device coaxially placed through a 5F balloon catheter can also solve this problem, as one or more occlusion devices can be placed distally and then proximally with flow stasis. The microcatheter deliverable occlusion device or device placed through a 5F balloon catheter (with flow stasis) can also be used to create a stable intravascular occlusion structure in the presence of high flow, as can be seen in the case of arteriovenous fistulas.

[0029] The present invention contemplates a medical occlusion device having multiple expansion modes, whereby the occlusion device can assume multiple shapes, each having a corresponding outer diameter. The expansion modes are powered or provided by different structural elements. For example, an occlusion device according to the present invention can assume a primary tubular shape, wherein the occlusion device has a self-expanding structure, typically a reconfigurable lattice woven from shape memory alloy wires in the manner of a conventional vascular stent. The primary tubular shape can assume a secondary shape, such as a helix or helix-like configuration, upon further expansion, exemplarily under the force exerted by dedicated shape memory members, such as wires disposed inside or partially inside the tubular structure.

[0030] The present invention contemplates an expandable vascular plug comprising a thrombogenic material disposed on an uncovered plug scaffold, an uncovered partially porous plug wall braid or mesh, or a semi-permeable covering or plug membrane. The thrombogenic material will change the porosity of the plug wall from high to low over time after initial deployment. Alternatively or additionally, the expandable vascular plug can be provided with a hydrogel coating or similar material that swells or expands upon contact with blood.

[0031] The present invention provides improved vascular occlusion devices and / or related methods of surgery that allow for the strategic placement of successive devices for better and safer treatment of long segment vascular lesions, such as elongated fusiform aneurysms (endovascular trapping). The method entails placement of an initial proximal occlusion device to reduce inflow to the lesion. The initial proximal occlusion device has a channel or passageway or plug hole that can be traversed with the same delivery catheter to place one or more downstream secondary occlusion devices relative to the vascular lesion. After deployment of the secondary occlusion devices distal to the first occlusion device, the catheter is withdrawn and used to place a final proximal device to occlude the proximal plug hole, thereby occluding the vascular segment at both ends on either side of each other.

[0032] The present invention provides improved vascular occlusion devices and / or related methods of surgery that allow for the initial treatment of saccular intracranial or peripheral aneurysms. Two covered or uncovered interlocking or intertwining devices can be assembled within the aneurysm sac to create aneurysm occlusion, thereby protecting the parent vessel. Occlusion of the aneurysm sac can alternatively be accomplished using a single improved expanded occlusion device that tapers at both ends, essentially presenting a corkscrew design along the leading and trailing ends of the occlusion device, thereby approximating the typical spheroid or ellipsoid shape of the aneurysm sac. The device outer wall for this purpose can be uncovered, covered with a microporous membrane, or covered with an impermeable membrane. BRIEF DESCRIPTION OF DRAWINGS

[0033] The accompanying drawings are schematic representations of various embodiments of vascular occlusion devices according to the present invention, which can alternatively be used to perform the methods according to the present invention.

[0034] Figure 1A is a schematic side view of the vascular occlusion device of Figure 1B compares to,

[0035] Figure 1B is a schematic side view of the vascular occlusion device of Figure 1A compares to, Figure 1A Figure 1B ​The expanded deployment or use configuration of the device has an axially compressed loop or coil.

[0036] Figure 2 is Figure 1A and 1B is a side view of a vascular occlusion device in a tubular, extended and slightly curled configuration, adapted to be collapsed and inserted into a deployment microcatheter.

[0037] Figure 3 is Figure 1A and 1B is a side view of a shape memory helical shaped wire element included in a vascular occlusion device.

[0038] Figure 4 is a magnified side view of a portion of a vascular occlusion device according to the present invention, showing a shape memory coil incorporated into the wall of a tubular body or within the lumen.

[0039] Figure 5 is a side view of a vascular plug or occlusion device substantially identical to 1A and 1B, showing the device within a schematically depicted blood vessel.

[0040] Figure 6 is Figure 4 is an end view of the device.

[0041] Figure 7A and 7B is a schematic side view of a vascular plug or occlusion device according to the present invention, showing different number of turns of the helical body member due to its different lengths.

[0042] Figure 8 is a schematic side view of a short vascular plug according to the present invention in an expanded configuration with minimal number of helical turns.

[0043] Figure 9 shows the plug of Figure 8 in different orientations.

[0044] Figure 10 is a schematic side view of a pair of interwoven and interlocked short vascular plugs according to the present invention.

[0045] Figure 11A is a side view of a vascular occlusion device of Figure 1A and 1B in a slightly curled configuration.

[0046] Figure 11B is a partial side view of a vascular occlusion device in a partially expanded and partially helical configuration, existing in a blood vessel that is too small to allow full expansion.

[0047] Figure 12is a partial side view of a pair of partially expanded vaso-occlusive devices in a double helix configuration deployed to fully occlude a blood vessel that is larger than the primary device diameter but smaller than the fully expanded secondary diameter.

[0048] Figure 13A and 13B is a side view of a pair of plugs or vaso-occlusive devices similar to Figure 12 deployed in series to occlude a blood vessel that is too small to allow the plugs or devices to fully expand. Figure 13B shows Figure 13A the internal shape memory element not depicted in

[0049] Figure 14A , 14B and 14C are side views of vaso-plugs or occlusive devices according to the present invention showing different states or degrees of secondary expansion or distortion as determined by the size or diameter of the blood vessel lumen in which the plugs or occlusive devices are deployed.

[0050] Figure 15 is a side view of a tapered helical plug or modified helical design that minimizes or eliminates the open central passage of a fully formed plug.

[0051] Figure 16A is a traditional fiber coil used clinically.

[0052] Figure 16B is an end view of a fully formed covered plug helix according to the present invention, the plug helix containing central thrombogenic fibers to promote closure of the open central passage or "doughnut hole".

[0053] Figure 16C is an end view of a fully formed uncovered plug helix, with thrombogenic fibers distributed through the interstices of the plug.

[0054] Figure 17A is a coil covered with an expanding hydrogel used clinically.

[0055] Figure 17B is an uncovered helical vaso-plug or occlusive device according to the present invention.

[0056] Figures 18A-18D depicts successive stages in a surgical procedure to isolate a fusiform aneurysm with a vaso-plug or occlusive device according to features of the present invention.

[0057] Figure 19A is a schematic longitudinal cross-sectional view of a blood vessel with a saccular aneurysm arising therefrom, depicting a plug or occlusive device deployed within the aneurysm sac.

[0058] Figure 19Bis a schematic longitudinal cross-sectional view of a blood vessel having a saccular aneurysm arising therefrom, depicting two deployed interlocking or intertwined plugs or occlusion devices within the aneurysmal sac.

[0059] Figure 20A is a schematic longitudinal cross-sectional view of a blood vessel having a saccular aneurysm arising therefrom, comprising a single deployed improved helical tapered occlusion device of longer length to occlude a saccular aneurysm having more of an elliptical shape.

[0060] Figure 20B is a schematic longitudinal cross-sectional view of a blood vessel having a saccular aneurysm arising therefrom, comprising a single deployed improved helical tapered occlusion device of shorter length to occlude a saccular aneurysm having more of a spherical shape.

[0061] Figure 21 is a schematic longitudinal cross-sectional view of the left atrial appendage of the heart, comprising two consecutively deployed interlocking or intertwined vascular occlusion devices, so as to occlude or block the left atrial appendage in accordance with the present invention in a method in accordance with features of the present invention.

[0062] Figure 22 is a schematic longitudinal cross-sectional view of the left atrial appendage of the heart, comprising a single deployed improved occlusion device, so as to occlude or block the left atrial appendage in accordance with the present invention in a method in accordance with features of the present invention. The improved occlusion device is tapered at both ends, essentially a tapered tubular helical design along the leading and trailing ends of the occlusion device, approximating the typical conical or elliptical shape of the left atrial appendage of the heart. DETAILED DESCRIPTION

[0063] The vascular occlusion device or plug of the present invention, such as plug 20 Figure 1A and 1B may be delivered through microcatheter 18, which can occlude a wide range of blood vessel sizes from small to large, which is not possible with currently available microcatheter delivery devices. This design allows for occlusion of blood vessels smaller and larger than 5 mm, which is the upper limit of current microcatheter deliverable plugs.

[0064] In an expanded deployed configuration as shown in Figure 1A and 1B the self-expanding and self-forming vascular plug or occlusion device 20 takes the expanded form of a three-dimensional helical tubular structure 22, optionally covered with an impermeable or partially permeable membrane 23, which allows for occlusion of large blood vessels through microcatheter 18, which is not possible with currently available devices.

[0065] Figure 1A shows the relative separation or separation of the coiled sections or windings 19 of the plug or occlusion device 20, while Figure 1BThe relative compression of the coiled section or winding 19 of the plug is shown, which can be achieved by retracting or advancing or deploying the line 21. Microcatheters (e.g., microcatheter 18) are small delivery catheters, typically manufactured with two different inner diameter sizes: 0.021 inches (standard) and 0.027 inches (high flow). Larger 4F and 5F delivery catheters can also be used to deliver larger diameter vascular plugs, typically with inner diameters of 0.040 inches and 0.046 inches, respectively. Therefore, the same design can be used for larger 4F and 5F delivery devices to occlude even larger arteries, veins, or aneurysms.

[0066] Vascular plug or occlusion device 20 includes a primary subunit in the form of a self-expanding tubular structure 22 (in Figure 2 (Seen in a spiral from the beginning), it is designed to optimize flexibility, conformability, and compressibility. The self-expanding tubular structure 22 is constructed of a shape memory material (such as nitinol or other metal alloys). More specifically, the tubular structure 22 is a mesh, network, or lattice of shape memory metal wires or strands 17 that are interconnected and selectively slide relative to each other so that the configuration of the tubular member 22 can change from a nearly linear configuration (not shown) that is tightly stretched when confined within the delivery conduit 18 to a more flexible configuration. Figure 2 The diagram shows an extended tubular form. This lattice is well-known in the medical industry because stents are often made from this structure.

[0067] The plug or occlusion device 20 also includes one or more secondary subunits, which are elongated shape memory shaped wires 24 made of a stiffer, coiled metal alloy (e.g., nitinol). Figure 1A , 1B 3). Each forming line 24 extends longitudinally through the tubular subunit or structure 22 of the primary cover to form or force the tubular subunit 22 into a helical or spiral configuration 92. Figure 1A , 1B ), which inherently possesses a higher degree of sophistication than primary subunits or tubular structures 22 ( Figure 2 A larger diameter and providing enhanced or increased outward radial force for pressing the primary subunit or tubular structure 22 against the endothelial surface and holding the plug or occlusion device 20 in the desired or target vascular location.

[0068] Device 20 forms itself into the primary tubular shape of subunit 22. Figure 2 ) and secondary helical or helical configurations 92 ( Figure 1A , 1B The ability to treat blood vessels of various sizes using a single device is a key feature of nickel-titanium alloys. The unique shape memory and superelasticity of nickel-titanium alloys make them ideal for producing secondary helical or spiral configurations. Figure 1A , 1B) and generate outward radial forces sufficient to anchor the vascular plug or occlusive device 20 to the endothelium of the target blood vessel, which opposes the downstream directed force exerted on the device during implantation, which is in part dependent on the permeability of any membrane 23 covering the device.

[0069] The coiled Nitinol forming wire or wires 24 can be fully incorporated into the wall 26 of the plug or occlusive device 20, for example, braided into the mesh or lattice of the tubular structure 22 along with the wires or strands 17, or freely float within the lumen thereof or partially incorporated or attached to the lattice wall 26 of the tubular structure 22 at two or more spaced points. Illustratively, each forming wire 24 can be connected to the end or closed points 25 and 27 of the tubular structure 22. Under its own internal force, the body or wall 26 of the tubular structure 22 exerts sufficient radial force to maintain a primary tubular shape but is flexible enough to assume a helical or spiral configuration 92 in response to the stronger spring force of the incorporated coiled Nitinol forming wire or spine 24.

[0070] Preferably, the device 20 includes a single forming wire 24 that forms the inner or small diameter curve of the helical or spiral configuration 92 (see Figure 1B and 6 ). The forming wire 24 is preferably attached to the tubular structure 22 at the ends 25 and 27 and braided or partially braided into the lattice of the tubular wall 26, or optionally free-floating within the lumen of the tubular structure 22. The internal spring force of the wall 26 maintains the tubular structure 22 in an open tube form and the helical or spiral secondary configuration 92 with the forming wire 24. In addition to forming the secondary shape, i.e., the helical or spiral configuration 92, the Nitinol forming wire 24 incorporated into the plug or occlusive device 20 substantially contributes to the outward radial force needed for device anchoring.

[0071] If the target blood vessel is too small for the primary self-expanding tubular subunit 22 to form a large secondary helical or spiral configuration 92 ( Figure 1A , 1B ), then the at least one internal helical wire or spring memory element 24 still plays a key role, i.e., to increase the radial force exerted on the tubular structure 22 of the device 20 for better vascular anchoring. The flexibility and conformability of the primary self-expanding tubular subunit or structure 22 is needed to create the helical, twisted or spiral configuration 92 of the tubular secondary design structure. The compressibility of the tubular subunit or structure 22 in the substantially cylindrical or minimally coiled configuration ( Figure 2 ) or the expanded or secondary helical or spiral configuration 92 ( Figure 1A , 1B ) is desirable to accommodate different blood vessel sizes.

[0072] The body or wall 26 of the tubular structure 22 can be laser cut from a Nitinol tube or created from braided or woven strands 17 made from Nitinol or other suitable metal alloys, including but not limited to cobalt-chromium alloys. Figure 14A

[0073] The braided design of the plug wall 26 allows for increased flexibility, conformability, and compressibility to facilitate the creation of a secondary plug shape, a helix or helical configuration 92. Figure 4 In addition to the method of plug body construction and design, the alloy that makes up the plug body and particularly its outer wall 26 can be selected to optimize the same properties. In contrast to an alternative design where the coiled Nitinol shape wire 24 is free within the lumen of the plug, the braided plug body or wall 26 can also facilitate the direct partial or complete incorporation of the coiled Nitinol shape wire 24 into the weave or braid of the plug wall 26. The shape wire can be fixed or able to move or slide relative to its point of attachment or anchoring within the plug wall or along its inner surface.

[0074] Where the vascular plug or occlusion device 20 includes a membrane covering 23, the membrane can be made from, but is not limited to, PTFE, TecoThane, Nylon, PET, Carbothane (Bionate), Fluoropolymers, SIBS, and PGLA. In addition to the uncovered downstream end that allows blood to enter and exit the plug body, the primary tubular plug subunit or structure 22 is preferably covered with an impermeable membrane 23 to facilitate plug repositioning or removal prior to final mechanical detachment. The upstream portion of the plug covering 23 is preferably impermeable to flow, while the downstream portion of the plug or occlusion device 20 can be porous or uncovered.

[0075] In another vascular plug or occlusion device 120, the plug body wall 126 is not covered Figure 17B The upstream portion 112 of the vascular plug or occlusion device 120 has a low porosity to facilitate stasis and thrombus formation, while the downstream portion 114 has a higher porosity to allow blood to flow into and out of the plug lumen (not designated) to enable the device 120 to be repositioned or removed prior to its final deployment.

[0076] ​Any plug or occlusion device 20 disclosed herein with very low porosity is more prone to thrombosis, while a plug or occlusion device 20 with higher porosity is less prone to migration under high flow conditions; higher porosity allows the operator to create an initial stable construct or scaffold with one or more uncovered plugs 20, followed by placement of one or more covered or very low porosity devices 20 to complete the vessel occlusion. Altering the weave pattern in the plug wall 26 or utilizing a porous plug covering or membrane 23 can alter the porosity of the plug wall 26.

[0077] In another vascular plug or occlusion device 220 (see Figure 16B , 16C , 17A), the plug body wall 226 is not covered with an impermeable membrane, but is coated with a variety of thrombogenic materials, including but not limited to small fibers 71 Figure 16B ) or hydrogels 75 Figure 17A to induce vessel thrombosis. As shown in Figure 16C , the thrombogenic fibers 171 can be distributed throughout the voids in the wall 174 of the uncovered plug 172 to promote vessel thrombosis.

[0078] Figure 17A Coil 73 covered with hydrogel 75 is depicted in Figure 17B . As shown, the braided or woven wire 117 of plug or occlusion device 120 can be coated with hydrogel 119 in a similar manner. An uncovered plug 120 coated with hydrogel 119 or similar substance can be valuable in high flow situations to prevent migration of the device over time as vessel thrombosis occurs. A hydrogel-coated plug 20 or 120 can be useful in high flow environments, allowing time to deploy two stable interlocking devices 20 or 120, inserted simultaneously through two delivery catheters or consecutively through one catheter, with the hydrogel 119 reducing the chance of device migration Figure 9 , 10 , 11, 12, 13). Commercially available hydrogel coatings can swell 80% in three minutes and reach maximum swelling after 20 minutes of contact with blood. Swelling of hydrogel 75 results in a 3-4 fold increase in effective size of the traditional coil 73 relative to baseline Figure 17A .

[0079] The tubular structure 22 of the vascular plug or occlusion device 20 is inserted into the delivery catheter 18 Figure 2 in a collapsed form Figure 1A , 1BThe plug or occlusion device 20 is inserted into the proximal end (not shown) of the delivery catheter 18 and advanced through the catheter using the advance line 21. This procedure is performed after the catheter is in place, with the distal tip (unspecified) at or near the target device deployment location, and the conventional guidewire (not shown) removed. Once the plug or occlusion device 20 reaches the distal end of the delivery catheter 18, the plug is unsheathed, for example by pulling back the delivery catheter 18 while securing or retaining the advance line 21. This method of inserting and ejecting the plug or occlusion device 20 from the catheter 18 is applicable to any plug or occlusion device described herein.

[0080] A number of well-known mechanisms (such as threads or interlocks) or electrolytic separation mechanisms may be used to release the plug 20 after the desired primary or secondary shape has been formed. This method for detachably attaching the plug or occlusion device 20 to the feed line 21 is applicable to any plug or occlusion device described herein. The plug or occlusion device 20 may be withdrawn and removed for any reason prior to final separation, including but not limited to improper sizing.

[0081] The plug or occlusion device 20 can be manufactured in various diameters and lengths to suit clinical purposes or vascular lesions. The plug or occlusion device 20 can be fully formed in a helical or spiral configuration. Figure 1A , 1B The total diameter of 5) can be twice the diameter of a cylindrical Seia unit or a tubular structure 22. Figure 2 For example, when fully formed into a curled or spiral shape ( Figure 1A , 1B When 5), the 4mm diameter tubular plug 22 will have a total outer diameter greater than 8mm, possibly in the range of at least 10mm. A fully formed helical or spiral configuration 92 ( Figure 1A , 1B The outer diameter of the plug or closure device is equal to the two diameters of the subunit or tubular structure 20 plus the width of the central open channel or passage 28. Figure 6 The diameter of the open central channel 28 is preferably smaller than that of a single primary tubular subunit or structure 22. The formation and diameter of the open central channel 28 vary depending on the size of the tumor-bearing vessel, the diameter of the primary device, and the compressibility of the entire plug configuration.

[0082] The plug or occlusion device 20 of different lengths, or the primary subunit or tubular structure 22 in its deployed configuration, can be provided based on clinical indications. Figure 2 Occlusive segmental vascular lesions or large fusiform aneurysms will benefit from longer-term devices (20a). Figure 7A In other applications, a shorter device 20b is indicated. Figure 7B The minimum length required to achieve a fully formed secondary spiral or helical shape is determined by the length required for the plug or closure device 20c to form a single 360-degree spiral. Figure 8 ).

[0083] After initial deployment (but before release), the clamping of the occlusion device 20 (or any modifications thereof described herein) can be achieved via delivery line 21, which produces a fully formed secondary shape from a partially twisted configuration according to the size of the tumor-bearing vessel. Delivery line 21 pushes the proximal-positioned coil or turn of the helical or spiral configuration 92 toward the more distally positioned coil or turn in the distal direction. Figure 1A and 1B The image depicts different degrees of compression of the device 20 in a fully extended spiral or helical configuration 92. The open central channel or "donut hole" passage 28 can be provided by a fully formed coiled or spiral plug 20 with a cover or membrane 23 (see...). Figure 6 The potential central channel or "donut hole" passage 28 can be occluded with a second plug or occlusion device 20', thereby creating an even more stable occlusion assembly. Figure 10 Alternatively, based on the remaining flow and the open central passage or pathway 28 ( Figure 6 The size of the coil is determined for this purpose.

[0084] In another form of the vascular plug or occlusion device 220 ( Figure 16B Thrombogenic fibers 71 are incorporated into the outer surface of the plug wall 26 to help close the open central channel or "donut-shaped" channel 28. Thrombogenic fibers 71 may attach to a helical nitinol coil or be incorporated into a secondary subunit 24 within the plug wall 26, forming a helical or spiral configuration 92 with an internal curve (see [link]). Figure 1A and 1B ), strategically positioning fiber 71 in the central channel or passageway 28 ( Figure 6 In this process, it promotes the formation of thrombi in the lumen. Figure 16B ).

[0085] The presence of a central channel or passage 28 is advantageous under high flow conditions to allow for a more stable final superstructure or component, preventing the first inserted vascular plug or occlusion device 20 from shifting before final occlusion is achieved with the second device 20'. Figure 10 See also Figure 12 , 13A Placing device 20 in a blood vessel slightly larger than the diameter of the primary subunit or tubular structure 22 results in a partially twisted or spiral secondary shape 30. Figure 11B This may result in some residual flow around the device. This is achieved by using the same delivery microcatheter 18 to pass through the first deployed plug 30 (see...). Figure 1A , 1B And place a second parallel partial helical plug or blocking device 32 interlocked with the first device 30 to produce a double helix configuration 34. Figure 12) to achieve complete occlusion.

[0086] Figure 13A and 13B Two interwound vascular plugs or occlusion devices 36, 38 of the type described above are depicted, each having shape memory wire or spine elements 40, 42 ( Figure 13B ) that tend to form the respective device into a helix or helix-like configuration. The devices 36 and 38 have the same or different diameters dl and d2 and are deployed consecutively, preferably through the same microcatheter, to achieve occlusion of a vessel 44 that is larger than the diameter dl, d2 of either of the devices 36, 38 but too small to form a maximum secondary helix shape of sufficient size to occlude the vessel.

[0087] Alternatively, if the target vessel TBV is smaller than the deployed tubular structure 46 of the primary plug or occlusion device 47 ( Figure 14A ), neither the partially coiled ( Figure 14B ) nor the fully expanded twisted shape ( Figure 14C ) can be formed and occlusion is achieved only by the deployed or substantially linear configuration of the primary vascular plug or occlusion device 47. The overall device configuration in the deployed occluded state is therefore dependent on the target vessel size at the implant site. In the deployment of the plug or occlusion device 47 in a vessel with a diameter smaller than the diameter d3 of the primary plug or occlusion device 47, the primary tubular shape or structure 46 remains in a substantially linear or straight form ( Figure 14A ). The vascular plug or occlusion device 47 is biased to obtain a twisted or helix-like configuration 50 ( Figure 14C ) in response to the outward force exerted by the shape memory nitinol wire or spine 52 within the plug wall 54 or within the lumen of the device. The twisted and curved extent of the secondary configuration 48 of the partially expanded vascular plug or occlusion device 47 ( Figure 14B ) makes this device very suitable for placement in a curved vessel or vessel segment where it conforms to the overall vessel shape and course. In vessels larger than the diameter d3 of the vascular plug or occlusion device 47 ( Figure 14A ) but smaller than or equal to twice the diameter d3, a partially twisted or partially expanded helix configuration 48 of the vascular plug or occlusion device 47 is naturally formed, possibly requiring a second parallel device 47 (to create a double helix configuration) or coil placement to eliminate any residual flow ( Figure 14B ). In vessels slightly larger than twice the diameter d3, a fully formed helix or helix-like configuration 50 of the vascular plug or occlusion device 47 is formed ( Figure 14C ) and a second centrally placed device or coil 47 can be required to eliminate any residual flow, this contingency being depicted in Figure 10In one embodiment, two plugs or occlusion devices 20 and 20' are shown, wherein device 20 is deployed and expanded into a helical or spiral form as shown, and plug 20' is subsequently inserted into a bore extending through a central passage (not designated) of the helical configuration of the deployed device 20.

[0088] It should be noted that the vascular plug or occlusion device 154 can be designed to have a fully expanded helical or spiral configuration tapered at opposite ends 156 and 158 as shown in Figure 15 In one embodiment, two plugs or occlusion devices 20 and 20' are shown, wherein device 20 is deployed and expanded into a helical or spiral form as shown, and plug 20' is subsequently inserted into a bore extending through a central passage (not designated) of the helical configuration of the deployed device 20.

[0089] In treating long segment vascular lesions, particularly useful in long segment vascular disease, such as elongated fusiform aneurysm 77 Figures 18A-18D It is contemplated that successive vascular plugs or occlusion devices 72, 76, 78, 80 be placed in a strategic manner (e.g., endovascular capture); this is accomplished by placing an initial proximal occlusion device 72 having a helical or spiral expanded configuration as shown in Figure 18A to reduce inflow into the aneurysm or lesion 77. Possible delivery catheters 79 include: microcatheters with inner diameters of 0.021 inch (standard) and 0.027 inch (high flow), and larger 4F and 5F delivery catheters for deployment of even larger diameter vascular plugs, which typically have inner diameters of 0.040 inch and 0.046 inch, respectively. The occlusion device 72 is designed to be passed through the plug bore, passage or access 28 (open central passage or space around partially twisted device, as shown in Figure 18B and 18C ) with the same delivery catheter 79 or a second delivery catheter 74 Figure 6shown) for placement of one or more downstream occlusion devices 76 and 78 relative to a vascular lesion or aneurysm 77. Subsequently, the catheter 79 or 74 is withdrawn through the aperture, channel or passageway 28 of the first placed proximal occlusion device 72 and used to place a final second proximal device 80 to close the aperture, channel or passageway 28 of the proximal occlusion device Figure 18D ). The vascular plugs or occlusion devices 72, 76, 78, 80 can all have a helical or spiral expanded configuration (not separately designated) and an internal spine 24 (see Figure 1A , 1B etc.) that is straight in the collapsed configuration of the respective plug or occlusion device 72, 76, 78, 80 within the catheter 79 or 74 and shapes the tubular outer wall 26 in the expanded configuration 92 into a helical or spiral deployed use configuration. Figure 1A , 1B While the plugs or occlusion devices 72, 76, 78, 80 are depicted as having less than two full (360°) turns or windings in the expanded helical or spiral configuration (not separately designated), it is understood that any of the devices can have more turns or windings. For example, the devices 72 and 76 can have three full turns while the devices 76 and 78 have two turns.

[0090] As shown in Figs. Figure 19A , 19B , 20A, 20B, one or the other form of vascular plug or occlusion device 20 also allows for a preliminary treatment of a saccular aneurysm 82. Instead of occluding the parent vessel, one or possibly two (covered or uncovered) interlocking or interwound occlusion devices 20 can be assembled within the aneurysm sac 82 Figure 19B ), resulting in aneurysm occlusion and thus protection of the parent vessel. Figure 19A Deployment of a single device 20 with about a single 360° winding or turn within a saccular aneurysm 82 is shown. Figure 19B Additional deployment of a second interwound device 20" is shown so that the two devices 20 and 20" together occlude or close the aneurysm sac 82. As shown in Figs. Figure 20A Occlusion of the aneurysm sac 82 can also be accomplished with a plug or occlusion device 154 (see also Figs. Figure 15 ), as shown in Figs. Figure 15 and 20A The plug or occlusion device 154 tapers at both ends 168 and 170. Essentially, the plug or occlusion device 154 presents a tapered tubular helical design along the leading end 170 and trailing end 168 of the occlusion device 154 and thus can also approximate the typical spheroid or ellipsoid shape of the aneurysm sac 82 depending on the length of the sac. Figure 20B The shorter device 154' depicted in Fig. Figure 20AThe longer device 154 depicted is more elliptical in shape. The device is delivered through a catheter 74 through the appropriate blood vessel through the patient's vasculature and into the sac aneurysm 82 where expansion is automatically achieved by the internal spring stress of the interwoven and oppositely sliding shape memory alloy wires or strands 152, 152' of the plug or occlusion device 154, 154'.

[0091] As Figure 21 depicted in the middle, two devices 20 and 20' can be assembled to one another to form an interlocking or interwound unit to occlude a large vessel space, such as the left atrial appendage 84, in the clinical setting of Figure 21 atrial fibrillation. Alternatively, occlusion of the left atrial appendage can be accomplished with a tapered or helical occlusion device 154 as shown in the bottom. Figure 22 The device 154 tapered at both ends 68 and 70 approximates the conical or elliptical shape of the left atrial appendage of the heart.

[0092] Described herein are covered self-expanding vascular plugs 20, 20' for occluding blood vessels. The plug design demonstrates the ability to form an expanded helical or spiral secondary shape from a tubular primary shape and configuration 92, allowing occlusion of a wide range of vessel sizes from small to large by microcatheter; this is not possible with current microcatheter deliverable plug designs. Currently, the largest diameter vessel that can be occluded by a microcatheter deliverable plug is 5 mm. The helical design described herein with the ability to create a large secondary shape, i.e., a spiral or helical configuration 92, also a feature of the improved occlusion device 120, 154, has the potential to occlude vessels much larger than currently possible with microcatheters. As discussed above with reference to Figure 19A , 19B , 20A, 20B, one or more devices 20, 20', 154 can also be placed directly within the lumen of a sac aneurysm 82, occluding its lumen while protecting the parent vessel.

[0093] In addition to the most distal portion of the plug, the vascular plug or occlusion device 20 is preferably covered with a thin, impermeable membrane 23 to allow blood to flow into or out of the device, enabling the device to be repositioned or removed prior to deployment. In another form of the device 20, the plug body is not covered with an impermeable membrane (uncovered), covered with a porous membrane or coated with a variety of thrombogenic materials, such as small fibers or hydrogels, to induce thrombosis through the three-dimensional helical superstructure or scaffold after deployment. The latter design (uncovered, covered with porous membrane, covered with fibers, or covered with hydrogels) can be valuable in high flow situations to prevent the initial device from migrating with vessel thrombosis over time. Similar results can be obtained by varying the plug wall weave pattern to vary the plug porosity or by covering the plug with a porous membrane.

[0094] One or more devices 20, 20', 120, 154 can be deployed through the same microcatheter 18 as needed to create stable interlocking subunits or constructs Figure 12 , 13A , 13B, 14A, 18C, 18D, 19B) to occlude large blood vessels or aneurysms 44, 77, 82. The helical or spiral configuration 92 allows for safe treatment of fusiform aneurysms 77 by initial complete segment occlusion across the entire aneurysm length with a single long device, or by sequential occlusion, first reducing inflow to the fusiform aneurysm with a proximal plug 72, then passing through the first plug with a delivery catheter 74 through an open channel or plug hole 28, then occluding distally with one or more plugs 76, 79, then completing proximal occlusion after withdrawal of the delivery catheter and placement of a final interlocking plug 80. Figures 18A-18D ).

[0095] Microcatheters commonly used in clinical practice have inner lumen diameters of 0.021 inch or 0.027 inch. The use of microcatheters allows access in tortuous vessels that would not be possible with larger 4 and 5F outer diameter delivery catheters, which typically have inner diameters of 0.040 inch and 0.046 inch, respectively. However, the same spiral plug design 20, 92 can be used to deliver even larger occlusion devices through these larger lumen catheters. The unique large space-filling capacity of the present helical tubular design can be used to occlude large arteries, veins, and aneurysms through small microcatheters, with a clear advantage over current methods. The ability to form larger secondary shapes from primary subunits according to the needs of the overall target vessel size is a key innovation. Multiple devices 20 can be deployed to form interwoven or interlocking structures or assemblies Figure 12 , 13A , 13B, 14A, 18C, 18D, 19B) that complete the occlusion of the vessel and occlude even larger vessel cross-sectional areas and volumes. Having a tapered end 68 and 70 as shown in Figure 15 , Figure 20A and 20B The improved device 154 with tapered ends 68 and 70 provides a mirror-symmetric helical design that eliminates the open central channel or passageway 28 present in the non-tapered version of the occlusion device 20. The improved tapered or helical design 154 can also be ideal for placement in a sac aneurysm 82 or occlusion of the left atrial appendage 84, resulting in a spheroid or ellipsoid shape. The occlusion device 20 can be made in various lengths (e.g., to Figure 1A and 1B with Figure 7A , 7B, 8, 9, depending on the anticipated need for secondary distortion or fully formed helical shaped configuration dictated by the target vessel size. The length and diameter of the primary subunit or tubular structure 22 can vary to adapt the device to different indications. The minimum device length is partially dependent on the need to form a fully formed secondary shape to create a 360 degree turn, which is an important consideration for occluding larger vessels. Longer lengths can be used to treat long segmental vascular lesions or to fill large vessel spaces, as can be seen in large aneurysms 77, 82.

[0096] While one or more second shaped wires can illustratively extend in a helical shape along the outer curve of the helical configuration 92, proximate the helical portion (not designated) of the outer wall 26 that engages the vessel endothelium when the device 20 is deployed, it should be appreciated that the outward force generated by such shaped wire can be generated by manipulating the internal shape memory of the wire or strand 17 of the tubular structure 22. Further, the large volume or cross-sectional area of the secondary helical or helical shaped configuration 92 of the vascular plug or occlusion device 20 (or 20', 20", 120, 154, etc.) naturally hinders device migration. Endothelial tissue naturally inserts into the continuous elongated gap or groove (not labeled) between adjacent turns or windings 19 of the device, thereby preventing downstream movement of the device. Such inserted endothelial tissue can be pinched or wedged between adjacent turns or windings 19, for example, during compression of the device 20 (or 20', 20", 120, 154, etc.), i.e., during the change in configuration from Figure 1A to Figure 1B Such pinching or wedging further aids in anchoring the helical or helical shaped configuration 92 at the selected deployment site in the target vessel. The physical size of the device 20 (or 20', 20", 120, 154, etc.) limits the requirement to generate excessive radial force, as the device will adhere to the endothelial wall of the vessel (44).

[0097] The plug or occlusion device 20 (or 20', 20", 120, 154, etc.) of the present invention can be used to occlude pathologic non-vascular spaces associated with the intestines, biliary ducts or ureters.

Claims

1. A medical device comprising an upper structure expandable from a collapsed insertion configuration sufficiently small to be introduced percutaneously into a patient's vasculature to a fully expanded coiled-in-use configuration sufficiently large to extend through a target blood vessel and engage the endothelial surface of such vessel, said upper structure in said insertion configuration being in the form of a collapsed self-expanding tubular structure expandable to said fully expanded coiled-in-use configuration, said fully expanded coiled-in-use configuration being a three-dimensionally twisted form of said tubular structure, said coiled-in-use configuration having tapered ends and proximal and distal convolutions, said tubular structure's outer wall tapering to a point at opposite ends in said coiled-in-use configuration to eliminate an open central passage formed by said three-dimensionally twisted form, said tubular structure being selectively expandable to any of a plurality of intermediate forms between a cylindrical configuration and said fully expanded coiled-in-use configuration, whereby said upper structure can engage the endothelium of a plurality of vessel sizes from small to large after minimally invasive delivery through a delivery catheter of a small fraction of the diameter of said tubular structure, the diameter of said tubular structure's outer wall again being a small fraction of the diameter of said fully expanded coiled-in-use configuration.

2. The medical device of claim 1 wherein said upper structure comprises an inner wire of shape memory material operatively connected to said tubular structure to form said tubular structure into said three-dimensionally twisted form.

3. The medical device of claim 2 wherein said inner wire is connected to said tubular structure at one or more points along the length of said outer wall.

4. The medical device of claim 2 wherein said inner wire is a crimped shaped wire incorporated into said outer wall.

5. The medical device of claim 2 wherein said inner wire is a crimped shaped wire disposed free in the lumen of said outer wall.

6. The medical device of claim 2 wherein said inner wire is a crimped shaped wire partially attached to a portion of said outer wall.

7. The medical device of claim 2 wherein said inner wire is a crimped shaped wire interwoven with said outer wall.

8. The medical device of claim 1 wherein said fully expanded coiled-in-use configuration has a diameter sufficiently large to extend through and occlude the largest blood vessels of the human cardiovascular system.

9. The medical device of claim 1 wherein said tubular structure is at least partially surrounded by a membrane.

10. The medical device of claim 1 wherein said tubular structure is at least partially covered by a membrane.

11. The medical device of claim 9 wherein said membrane is made of a flow impermeable material.

12. The medical device of claim 9 wherein at least a downstream portion of said membrane is made of a porous material.

13. The medical device of claim 9 wherein at least a trailing portion of said membrane is made of a porous material.

14. The medical device of claim 1, wherein the tubular structure is at least partially covered with a thrombogenic material such that the device, when implanted or deployed in a blood vessel, causes gradual vascular thrombosis, reducing the chance of flow-related device migration.

15. The medical device of claim 14, wherein the thrombogenic material is selected from the group consisting of small fibers and hydrogels.

16. The medical device of claim 1, wherein the three-dimensionally twisted form of the tubular structure has a plurality of turns of corresponding outer diameters, the plurality of turns of corresponding outer diameters including at least one central turn intermediate two opposite ends, the at least one central turn having an outer diameter greater than a maximum outer diameter of proximal turns, the fully expanded coiled configuration having an arcuate shape tapering from the at least one central turn to the two opposite ends.

17. The medical device of claim 16, wherein the tubular structure has a cross-section and associated outer diameter tapering from the at least one central turn to the two opposite ends.

18. The medical device of claim 16, wherein the three-dimensionally twisted form of the tubular structure has an overall shape of an ellipsoid or an ovoid.

19. The medical device of claim 1, wherein the upper structure further comprises an inner thread made of a shape memory material and attached to an outer wall of the tubular structure at two mutually spaced locations, the inner thread being further attached to the outer wall at at least one additional location between the two mutually spaced locations.

20. The medical device of claim 19, wherein the inner thread is slidably attached to the outer wall of the tubular structure at the at least one additional location.

21. The medical device of claim 20, wherein the inner thread is woven into the outer wall of the tubular structure at the at least one additional location.

22. The medical device of claim 1, wherein the three-dimensionally twisted form of the tubular structure is helical.

23. A kit comprising the medical device of claim 1 and further comprising an expandable plug configured for interweaving or interlocking with the medical device of claim 1, the medical device and the expandable plug being deployable in cooperation with each other for large vessel occlusion and catheter delivery.

Images