The invention relates to devices for blocking emboli in an aorta from entering arteries.
Devices such as intra-vascular filters may be inserted into a blood vessel prior to or during a procedure or at another time. Such devices may be inserted by way of a catheter that may be threaded through a vein or artery and into, for example, an aorta or other vessel where the device may be released from the catheter and, for example, deployed. The device may filter, deflect, or block emboli or other objects from entering into a blood supply that feeds the brain.
In a first aspect, the present invention provides an intra-vascular device for deflecting emboli, the device having a lateral structure, a filter, and two wires connected to the lateral structure. The lateral structure may circumscribe an elongate shape (e.g., elliptical, oval, or other non-rectilinear shape) with a length between 80 mm and 120 mm, and a width between 30 mm to 45 mm. The lateral structure may be sized such that upon installation of the device in the aortic arch of a human subject, it contacts the upper walls of the aortic arch. Further, a substantially planar, elongate (e.g., elliptical, oval, or other non-rectilinear shape) filter may be attached to the length and width of the lateral structure. The first wire may be attached to the distal end of the lateral structure, and the second wire may be attached to the proximal end of the lateral structure.
In additional embodiments, the lateral structure of the device forms a seal with the walls of the aortic arch, upon installation of the device in the aortic arch. In some embodiments, the filter of the device extends beyond the perimeter circumscribed by the lateral structure, e.g., to form a seal against the blood vessel wall, e.g., aortic arch.
The pores of the filters of the above-devices can be sized such that they are permeable to blood, (e.g., red blood cells (erythrocytes), white blood cells (leukocytes), platelets (thrombocytes), and plasma) but not significantly permeable to emboli, e.g., having a dimension of greater than 50, 100, or 200 μm.
In certain embodiments, the two wires of the device can have the same or differing stiffness (e.g., the first wire can be stiffer than the second, or the second wire can be stiffer than the first) and can be readily malleable. The device can be made from metal, e.g., Nitinol wire. The diameter of the wires and lateral structure of the device can be 1, 0.5, 0.25, 0.1 mm, or less. The lateral structure and/or a first and/or a second wire can be formed by twisting two or more wires together to form a composite wire with the desired thickness (e.g., having a diameter less than about 0.5 mm) and stiffness.
In certain embodiments, a first and/or a second wire is attached to the filter or lateral structure along the length of the lateral structure (e.g., along a midline of the lateral structure). In certain embodiments, the second wire is a hollow tube.
In one embodiment, the first wire of the device has a screw-like mechanism positioned at its distal end, and the filter or lateral structure of the device includes a mating component at its distal end that is suitable to receive the screw-like mechanism. The mating component of the filter or lateral structure of the device may include a bead, e.g., a spherical bead, attached near the distal end of the filter, or additional elements to irreversibly or reversibly connect the lateral structure or filter to the first or second wires (e.g., a screw and recess to accept the screw or a ball and snare mechanism). The additional elements may include one or more (e.g., 2, 3, 4, or more) ball(s), e.g., spherical ball(s), or tip(s) at the distal and proximal ends of the lateral structure. A first and/or second wire of the device may also include a snare that may join with a bead, ball, tip, or other receiving element attached to the filter or lateral structure of the device.
Any of the above embodiments, the devices of the invention can further include radiopaque markers.
In another aspect, the invention features a system for deflecting emboli, which includes any of the aforementioned embodiments of an intra-vascular device having a lateral structure, a filter, and first and second wires; and a catheter, into which the device can be loaded. In some embodiments, the catheter of the system contains a guide wire.
The above systems can further include a protected lip at the distal end of the system. The protected lip can be a dilator (e.g., with a diameter smaller than the catheter), which is positioned distal to the catheter. The systems of the invention may also include a pigtail catheter.
In one embodiment of the system of the invention, when loaded into the catheter, the lateral structure and filter of the device can be compressed, e.g., and positioned behind a dilator, if present. In another embodiment, the lateral structure and filter of the device expands upon retraction of the catheter relative to the device (or advancement of the device relative to the catheter). The catheters described above can have a distal opening that is perpendicular to the length of the catheter or non-perpendicular to the length of the catheter. The angle of the opening can be adjusted to permit delivery of the device in a desired orientation.
In another aspect, the invention features methods of introducing any of the above devices into a subject by inserting into a blood vessel (e.g., the aortic arch) of the subject a catheter containing the device (the device can be loaded into the catheter prior to or after introduction of the catheter into the subject). The device can be loaded into the catheter by applying force to, e.g., the first wire. Upon retraction of the catheter relative to the device (or advancement of the device relative to the catheter), the lateral structure and filter deploy into the blood vessel at a desired location, for example, into the aortic arch. Furthermore, upon installation in an aortic arch, the lateral structure and/or filter of the above devices can be capable of forming a seal with the walls of the blood vessel (e.g., aortic arch). The device can be positioned within the aortic arch by antagonistically pushing and pulling on the first and the second wires.
In certain embodiments, the device is loaded into a catheter prior to, or after introduction of the catheter into a subject. The catheter can further include a guidewire. A pigtail catheter may also be introduced through the catheter. Further, the pigtail catheter may be inserted over a guidewire that may be retracted through the catheter prior to deployment of the device.
As used herein, the term “substantially planar” refers to a radius of curvature of no more than 80 mm (e.g., no more than 10 mm, 20 mm, 30 mm, 40 mm, 50 mm, 60 mm, or 70 mm).
As used herein, the term “elongate” refers to a shape having a length that is greater than its width.
As used herein, the term “provide structural support” refers to the property contributing to shape and stiffness of the device.
As used herein, the term “wires” refers to any elongated structure (e.g., cords, fibers, yarns, filaments, cables, and threads) fabricated from any non-degradable material (e.g., polycarbonate, polytetrafluorothylene (PTFE), expanded polytetrafluorothylene (ePTFE), polyvinylidene fluoride (PVDF), polypropylene, porous urethane, metal, Nitinol, fluoropolymers (e.g., Teflon®), cobalt chromium alloys (CoCr), and para-aramid (Kevlar®), or textile (e.g., nylon, polyester (e.g., Dacron®), or silk).
As used herein, the term “pigtail catheter” refers to a surgical device that is used to introduce radio-opaque contrast for implant (e.g., a prosthetic aortic valve) confirmation. As used herein, the term “dilator” refers to a surgical instrument that is used to make a bodily orifice, such as a blood vessel, become wider, larger, or more open.
The present invention relates to methods of inhibiting the potentially harmful passage of particulates through the blood stream. Particulates that may be present in blood include, without limitation, blood clots, calcified debris, and emboli. While extremely small particulates may not cause significant harm, passage of larger particulates can result in stroke or other adverse outcomes. The risk of damage resulting from the passage of particulates can increase in association with certain conditions or medical procedures that perturb the vasculature. In order to moderate these risks, the invention features an intra-vascular device having a filter which is used to prevent particles in a blood vessel from passing through the filter, a lateral structure to support the filter, and two wires attached the lateral structure, one each at its distal and proximal ends. The lateral structure is substantially planar and does not include any supporting members that extend above or below the plane of the filter. In preferred embodiments, the two wires attached to the ends of the lateral structure may be used to deflect or control the orientation of the filter, after it has already been positioned within a blood vessel (e.g., the aortic arch). The two wires can be capable of readily moving through a delivery system to deliver the device to a desired location, and they can be pushed and pulled antagonistically to deflect the device.
In some embodiments, after the filter has been installed within the blood vessel and oriented as desired via use of the two wires, these wires may then be detached from the device leaving behind only the filter and its lateral structure in the blood vessel. This detachment may be facilitated by a screw-like mechanism attached to the distal end of a first wire of the device that is suitably mated to an element attached to the distal end of the filter, lateral structure, or another part of the device. The mating element attached to the device capable for conjoining the screw, or a suitable alternative, may be a bead.
In another embodiment, the device features a small ball or tip attached to the lateral structure at both its proximal and distal ends. Such an embodiment allows for attachment of a first and/or second wire to the lateral structure via a snare positioned around each small ball or tip. The snare, when attached to the tip or the ball, allows for deflection or control of the orientation of the device by pushing and pulling on the first and second wires. One, or both, of the wires may be detached from the lateral structure via the removal of the snares from around the attached ball or tip. These additional features of the device may remediate potential entanglement between the first wire and any instrumentation that may be passed between the first wire and the filter, for instance.
One of the wires of the device may be attached or sewn onto the filter or the lateral structure within the same plane or the filter or the lateral structure. For example, the wire may be attached along the middle of the filter and allow for bending of the first wire and filter into a concave shape prior to use. The bent wire may be rigid and attached to the filter, for instance, on its upper side. The filter may alternatively have a hollow tube, made of a stable, flexible material, positioned and attached along the length (e.g., midline) of the filter. The hollow tube may be the second wire of the device. In some embodiments, the tube has a first wire passing through it, capable of moving back and forth within the tube, which results in the overall deflection of the tube and as such, a change in the shape of the filter. Such a tube may include two stoppers, one positioned at each end, to contain and control the movement of the wire within the tube.
The device may have a non-symmetric design with respect to the orientation of the wires to the lateral structure. In an alternative embodiment, the device has a symmetric design, which allows for the filter to be oriented in an upright, concave manner or an inverted, convex manner. The device may also feature one or more ends that may be thinner or narrower than the rest of the device. The narrowing of the ends of the device may terminate in a rounded knob shape but not a point.
The lateral structure of the device provides, e.g., structure to the filter, and can facilitate control of the filter within the anatomy of the primary blood vessel. For example, this lateral structure can permit an operator to control the orientation of the device within the primary blood vessel to press the device against certain features of the primary blood vessel (e.g., to press the device against the orifice of one or more secondary blood vessels or against the walls of the primary blood vessel). The devices of the invention may feature a lateral structure that is a spring ring wire frame made of, for example, a flexible material. This spring ring frame can be shaped into an oval or elliptical shape. In some embodiments, the devices of the invention can also feature an outer lateral structure connected to an internal lateral structure to form a skeleton with, for example, an elliptical shape. The outer lateral structure can provide additional structural support for the device and can facilitate the creation of a seal between the filter of the device and a blood vessel wall. Alternatively, the filter itself may create a seal against the blood vessel wall by extending beyond the perimeter of the lateral structure.
The device of the invention may include a filter, a lateral structure with no supporting members extending beyond its plane, and two wires. The device can filter and/or deflect emboli or other large objects from entering protected secondary vessels. The device may be capable of collapse along its longitudinal axis for ease of delivery to the treatment site. The device may further be compatible with common delivery methods used in interventional cardiology (e.g., TAVI procedures). The device may be integrated into a delivery, e.g., a catheter, system. In some embodiments, the device may be detachable from the delivery wires. Upon retrieval, the device may be retracted in an orientation substantially similar to the original deployment orientation.
Any of the lateral structures or delivery wires of the devices of the invention can be fabricated in whole or in part from, e.g., Nitinol or other metal wire, superelastic or shape memory alloy material, readily malleable material, or nylon. The metal wire may include, e.g., tantalum or platinum. The diameter of the wire of the devices may be less than or equal to 1.0 mm (e.g., 1.0, 0.5, 0.25, 0.1 mm, or less). The thickness or diameter of the wire of the lateral structures and/or delivery wires may have different thicknesses to confer differing properties such as rigidity or flexibility. For instance, the lateral structures of the devices can be stiffened by the inclusion of one or more (e.g., 1, 2, 3, 4, 5, or more) twists of the wire. Furthermore, multiple wires of a certain gauge can be wound together to increase the stiffness of the lateral structure (e.g., the lateral structure can include 2, 3, 4, 5, or more wires of to increase the stiffness of the intra-vascular device).
The filters of the intra-vascular device of the invention can include a mesh (e.g., a mesh fabricated with Nitinol or other metal wire, nylon, or a combination of both) or perforated film. In devices where a mesh is present, the filter mesh can be rectilinear (e.g., square) or rhomboid. In devices where the pores of the filter are rectilinear or rhomboid, one or both lateral dimensions of the pore can be between 50 and 1000 microns (e.g., 100, 200, 300, 400, 500, 600, or more microns). When a perforated film is present, the pores formed in the perforated film include a varied or unvaried shape, have a varied or constant density across the film, and/or have a constant or varied size. The size of the pores of the filter allows the passage of blood cells (e.g., red blood cells (erythrocytes), white blood cells (leukocytes), platelets (thrombocytes), and plasma), while being impermeable to emboli or other undesirable particles larger than the pore dimensions. Emboli filtered by the filter of the present invention are typically emboli or other endothelial particles larger in one or more dimensions than an aperture of the mesh of the filter. Emboli filtered by the intra-vascular device of the present invention may be sized to have a dimension greater than 50 μm, e.g., 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 200 μm, 300 μm, 400 μm, 500 μm, or 1000 μm or more.
In various embodiments, it is desirable to track the progress of all or a portion of the device of the present invention or of a treatment apparatus used in conjunction with the device of the present invention. A variety of mechanisms for tracking the progress of all or a portion of a device, e.g., by visualizing progress, are contemplated. Methods of tracking include, without limitation, X-ray, fluoroscopy, ultrasound, echocardiography, MRI (magnetic resonance imaging), direct angioscopy, near infrared angiology, intra-vascular ultrasound, CT (computerized tomography) scan, and/or any other suitable imaging technology.
In certain instances, a device may require one or more modifications to facilitate one or more methods of tracking the progress of all or a portion of the device. In particular embodiments, one or more radiopaque elements are attached to, included in, or integrated with the device. For example, portions of the lateral structure or filter can be constructed out of Drawn Filled Tubing (DFT wire). Such wire can contain a core of tantalum and/or platinum and an outer material of Nitinol. In certain embodiments, the DFT wire can be incorporated into all or a portion of the intra-vascular device lateral structure, wires, or filter. In embodiments where radiopaque wire (e.g., DFT wire) is used in the filter, it can be used throughout the filter or in a certain subset thereof.
In particular embodiments, including some in which multiple radiopaque elements are attached to, included in, or integrated with a device, it is possible to detect both the progress and particular orientation of all or a portion of a device. In still more particular embodiments, a plurality of radiopaque elements are attached to, included in, or integrated with the filter in a manner that is irregular in two or three dimensions of one or more conformations of the filter, such that the location, orientation, and/or conformation of the filter is indicated upon detection of the radiopaque elements.
The invention also features methods of use of the intra-vascular devices having a filter which is used to prevent particles in a blood vessel from passing through the filter, a lateral structure to support the filter, and two wires attached the lateral structure, one each at its distal and proximal ends. The devices of the invention may be inserted into an aortic arch of a subject. The length of the device may be from approximately 80 mm to 120 mm, or otherwise as may be necessary to approximate a distance between an upper wall of an ascending aorta of a subject, upstream of an opening of an innominate artery and at an upper wall of a descending aorta of a subject downstream of an opening of a left subclavian artery. The width of the device may be from 30 mm to 45 mm or otherwise as may approximate an internal diameter of an aorta of a subject. The device may be introduced into a blood vessel of a subject in a collapsed form and contained within a catheter. A pigtail catheter may also be introduced through the catheter to enable visualization and positioning of the device. The pigtail catheter may be inserted over a guide wire, which can be subsequently retracted through the catheter before the device is deployed. The first wire of the device may be utilized to advance the device through the catheter. Upon reaching the desired location within the blood vessel of a subject, the catheter may be retracted, enabling the lateral structure and filter of the device to assume an extended form upon its release or deployment from the catheter. The position of the device in the desired location, such as the aortic arch, can be adjusted by antagonistically pushing and pulling of the first and second wires of the device. In the desired position, the device may extend the filter attached to the lateral structure so that the filter assumes a position approximately midway between an upper wall of the aortic arch and a lower wall of the aortic arch, and extends over the distance between the branch arteries of the aorta. The positioned device filters embolic material from entering the branch arteries of the aorta.
In one embodiment, a device according to an embodiment of the present invention can be used for protection of the brain from emboli prior to, during, and/or after an invasive intracardiac procedure, such as balloon aortic valvuloplasty, balloon mitral valvuloplsty, electrophysiological studies, with or without ablation of ectopic rhythmic sites, insertion of automatic defibrillators, percutaneous valve repair or replacement, or other procedures. Embodiments of the device can be used, for example, in subjects with severe aortic atheroma for brain protection during routine heart catheterization, or for endovascular “cleaning” of atheromatous or thrombotic material. Such an embodiment could be used in subjects with high risk or propensity to form intracardiac clots, for example subjects with hematological disease, arrhythmia of the heart, artificial heart subjects, assist-device subjects, mechanical valve replacement subjects, subjects following intracardiac repair of a pathology, or subjects with congenital heart disease such as patent foramen ovale, and so forth. Other applications of blood particulate filters, medical procedures that benefit from the use of blood particulate filters, and patients at risk of damage resulting from blood particulates are known in the art.
A device according to an embodiment of the present invention can be used, for example, temporarily for acute conditions. For example, the device can be inserted for the duration, or the known duration, of the condition. For example, the device may be inserted temporarily to protect against cardio embolic stroke or embolic stroke. The device of the present invention may be used to reduce the risk of damage resulting from blood particulates, such as emboli in subjects from suffering conditions associated with an elevated risk thereof, such as acute myocardial infarction (AMI). Thus, in further embodiments, the device may be inserted for the duration of a procedure or treatment. In other embodiments, the device may be inserted for a long-term period, or permanently.
One particular use or outcome of the use, of many embodiments of the present invention includes the prevention of particulates from reaching the brain or preventing blood flow to the brain.
A device of the present invention may be used in conjunction with one or more pharmaceutical compositions, such as a drug known to treat endocarditis or blood clots.
Reference is made to
In some embodiments, the diameter of the dilator 101 positioned within catheter 103 may be sufficiently small such that the guide wire 102 may move past the dilator 101, when both are simultaneously present in the catheter. Once the catheter 103 is partially withdrawn, the IVD 100 may unfold, and the dilator 101 may be withdrawn via the catheter 103. The dilator 101 may be sufficiently flexible to be withdrawn via the catheter 103 despite the continued presence of, for example, various wires within the same catheter 103. In some embodiments, there is sufficient space for a pig tail catheter 104 to be inserted over the guide wire 102, via the catheter 103, into the ascending aorta. Other methods of implanting IVD 100 into a blood vessel are possible.
Reference is made to
In some embodiments, lateral structure 200 may include, or be constructed of Nitinol or other superelastic or shape memory alloy or material. Other materials may be used to make the lateral structure and the skeleton.
In some embodiments, a circular, spring ring wire frame 209 may be made into inner lateral structure 200b having an elongate shape, which may form the part of skeleton 207 of IVD 100. The inner lateral structure 200b may exert a residual outward force 208 which may help it position itself in, for example, an aortic arch 205 and may help prevent particles such as, emboli, from entering the carotid branches 204. The filter 201 may or may not be substantially planar. As depicted in
Reference is made to
In some embodiments, a first wire 202 is attached to the distal end of the device's lateral structure 200 and a second wire 203 is attached to the proximal end of the lateral structure. In some embodiments, the first wire 202 is stiffer than the second wire 203 and upon installation of the device in, for example, an aortic arch 205, these wires (202, 203) may be pushed and pulled antagonistically to deflect IVD 100. These wires (202, 203) may be used to deliver the device to a given location within, for example, a blood vessel and may also be capable of readily moving through a catheter 103.
Reference is made to
In some embodiments, both the first wire and second wire (202, 203) are of equal stiffness. In some embodiments, the guide wire 102 passes through the filter 201 at a distal position. In some embodiments, the catheter 103 presses against the guide wire's (102) passage way at the lateral structure 200 of the filter 201, which may cause the guide wire 102 to release itself from the filter 201 allowing, for example, the catheter 103 to advance further down the blood vessel.
In some embodiments, the end of the catheter 103 positioned inside, for example, a blood vessel, has an opening that is not perpendicular to the longitudinal axis of the catheter 103. Reference is made to
Reference is made to
Reference is made to
Reference is made to
There may be multiple ways of connecting the first and/or second wires (202, 203) to the filter 201 of the IVD 100. In some embodiments, a snare 701 is positioned at the end of the first and/or second wires (202, 203). This snare 701 may be looped onto a tip 700 at the ends of the frame 200 of the filter, allowing the wires (202, 203) to be attached and detached from the filter 201 accordingly. In some embodiments, the first and/or second wires (202, 203) include a screw-like mechanism 401 at their distal extremity. This screw-like mechanism 401 may be able to receivingly conjoin with suitable elements, such as a bead 400 situated on the lateral structure 200, filter 201, or another part of the device. Through screwing and unscrewing the first and/or second wires (202, 203) may be attached or detached respectively, from the rest of IVD 100. Other methods of attaching and detaching the first and/or second wires to IVD 100 may be possible.
In still other embodiments, IVD (100) is adapted for use with other embolism protection devices (e.g., those described U.S. application Ser. Nos. 13/300,936, and 13/205,255; in U.S. Publication Nos. 2008-0255603 and 2011-0106137; and in U.S. Pat. Nos. 8,062,324 and 7,232,453), each of which is hereby incorporated by reference in its entirety.
All publications and patents cited in this specification are incorporated herein by reference as if each individual publication or patent were specifically and individually indicated to be incorporated by reference. Although the foregoing invention has been described in some detail by way of illustration and example for purposes of clarity of understanding, it will be readily apparent to those of ordinary skill in the art in light of the teachings of this invention that certain changes and modifications may be made thereto without departing from the spirit or scope of the appended claims.
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/IB2015/000410 | 1/9/2015 | WO | 00 |
Number | Date | Country | |
---|---|---|---|
61926142 | Jan 2014 | US |