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This application claims the benefit under 35 U.S.C. § 119(e) of provisional application US 62/409,887 filed 19 October 2017 and entitled "Intravascular Trap"; which is fully incorporated herein by reference.

FIELD OF THE INVENTION

The various described embodiments are in the field of intravascular filtration.

BACKGROUND OF THE INVENTION

Intracardiac and intravascular procedures/operations can liberate particulate debris in blood vessels. Particulate debris in the vascular system contributes to complications including vascular occlusion, end-organ ischemia, stroke, and heart attack. Various ways to filter this debris from the vascular system before it arrives at distal organs have been proposed.

Filters deployed in the arterial system capture particulate debris in the blood. In many cases, captured particles escape the filter during diastole and/or during filter removal.

Examples of intravascular filters are described in, for example, US 7,758,606 and US 7,537,600.

SUMMARY OF THE INVENTION

A broad aspect of the invention relates to intravascular filtration. In describing the various embodiments of the invention the term "proximal" indicates a portion of the trap through which blood enters during systole and the term "distal" indicates a portion of the trap through which blood enters during diastole. Use of traps described herein presumes that a location of a source of particulate is known so that the trap can be positioned and oriented correctly.

One aspect of some embodiments of the invention relates to an intravascular trap with no moving parts. Moving parts, as used here, refers to hinges, flaps, doors, valves and other active mechanisms. Optionally, portions of the trap are constructed of materials which are sufficiently flexible that they bend or flex in response to changes in blood pressure and/or flow direction.

In some exemplary embodiments of the invention a body of the trap is constructed primarily of polymeric membrane or mesh. In some embodiments the body of the trap is supported by struts and/or rings. Alternatively or additionally, in some embodiments cords restrict changes in orientation between various parts of the trap.

Another aspect of some embodiments of the invention relates to a trap including a proximal funnel with a wide aperture on the proximal side and a narrow aperture on the distal side. In some embodiments, walls of the funnel are constructed primarily of polymeric membrane or mesh. In some embodiments walls of the funnel guide particle to the narrow aperture while allowing liquid to flow though the wall. Alternatively or additionally, in some embodiments the apertures of the funnel are defined by rigid rings. According to various exemplary embodiments of the invention the diameter of the narrow aperture is narrower than the diameter the wide aperture by a factor of 2, 3, 4, 5, 5.5 or 6 or intermediate or greater ratios. In some embodiments, increasing this ratio contributes to an increase inefficiency of the trap.

Another aspect of some embodiments of the invention relates to a trap including a distal particle filter adapted to guide particles radially outward from the center of the filter during systole. In some embodiments the particle filter includes a center region which is convex towards the proximal side. Alternatively or additionally, in some embodiments the center region of the particle trap is aligned with a center of the narrow aperture of the funnel. In some embodiments the center region of the particle trap and the centers of the two apertures of the funnel are positioned along a linear axis of a blood vessel in which the trap is installed.

Another aspect of some embodiments of the invention relates to a trap including a proximal funnel joined to a distal trap by a common ring.

It will be appreciated that the various aspects described above relate to solution of technical problems associated with retention of particles within an intravascular trap during diastole.

Alternatively or additionally, it will be appreciated that the various aspects described above relate to solution of technical problems related to retention of particles within an intravascular trap during removal of the trap. In some exemplary embodiments of the invention, there is provided an intravascular trap including: (a) a proximal funnel with a wide aperture on the proximal side and a narrow aperture on the distal side; and (b) a particle filter adapted to guide particles radially outward from the center of the filter during systole. In some embodiments the trap includes outer walls connecting the funnel and the filter. Alternatively or additionally, in some embodiments the trap includes a ring which defines the wide aperture. Alternatively or additionally, in some embodiments the ring engages the walls. Alternatively or additionally, in some embodiments the trap includes a ring which defines the narrow aperture. Alternatively or additionally, in some embodiments a diameter of the narrow aperture is narrower than a diameter of the wide aperture by a factor of at least 2. Alternatively or additionally, in some embodiments a distance between the narrow aperture and the wide aperture is at least 0.3 mm. Alternatively or additionally, in some embodiments a distance between the narrow aperture and the wide aperture is less than 30 mm. Alternatively or additionally, in some embodiments the filter includes a center region which is convex towards its proximal side. Alternatively or additionally, in some embodiments a distance between the narrow aperture and the center region is at least 0 mm during systole. Alternatively or additionally, in some embodiments a distance between the narrow aperture and the center region is less than zero during systole. Alternatively or additionally, in some embodiments the trap includes struts adapted to support a portion of the trap. Alternatively or additionally, in some embodiments the trap includes cords adapted to restrict changes in orientation between various parts of the trap.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although suitable methods and materials are described below, methods and materials similar or equivalent to those described herein can be used in the practice of the present invention. In case of conflict, the patent specification, including definitions, will control. All materials, methods, and examples are illustrative only and are not intended to be limiting.

As used herein, the terms "comprising" and "including" or grammatical variants thereof are to be taken as specifying inclusion of the stated features, integers, actions or components without precluding the addition of one or more additional features, integers, actions, components or groups thereof. This term is broader than, and includes the terms "consisting of and "consisting essentially of as defined by the Manual of Patent Examination Procedure of the United States Patent and Trademark Office. Thus, any recitation that an embodiment "includes" or "comprises" a feature is a specific statement that sub embodiments "consist essentially of and/or "consist of the recited feature.

The phrase "consisting essentially of or grammatical variants thereof when used herein are to be taken as specifying the stated features, integers, steps or components but do not preclude the addition of one or more additional features, integers, steps, components or groups thereof but only if the additional features, integers, steps, components or groups thereof do not materially alter the basic and novel characteristics of the claimed composition, device or method.

The phrase "adapted to" as used in this specification and the accompanying claims imposes additional structural limitations on a previously recited component.

The term "method" refers to manners, means, techniques and procedures for accomplishing a given task including, but not limited to, those manners, means, techniques and procedures either known to, or readily developed from known manners, means, techniques and procedures by practitioners of architecture and/or computer science.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to understand the invention and to see how it may be carried out in practice, embodiments will now be described, by way of non-limiting example only, with reference to the accompanying figures. In the figures, identical and similar structures, elements or parts thereof that appear in more than one figure are generally labeled with the same or similar references in the figures in which they appear. Dimensions of components and features shown in the figures are chosen primarily for convenience and clarity of presentation and are not necessarily to scale. The attached figures are:

Fig. la is a perspective view of an intravascular trap according to some exemplary embodiments of the invention;

Fig. lb is an exploded view of the intravascular trap depicted in Fig. la; Fig.2a is a schematic side view of an intravascular trap according to some exemplary embodiments of the invention deployed in a blood vessel during systole;

Fig. 2b is a schematic side view of an intravascular trap as in Fig. 2a deployed in a blood vessel during diastole; and

Fig. 3is a schematic side view of an exemplary assembly including an intravascular trap according to an embodiment of the invention installed on a catheter.

DETAILED DESCRIPTION OF EMBODIMENTS

Embodiments of the invention relate to intravascular traps and methods of installation and use thereof.

Specifically, some embodiments of the invention can be used to trap particles freed into the bloodstream as a result of a cardiac procedure (e.g. angioplasty, TAVI, intravascular operation, heart operation or stent placement).

The principles and operation of an intravascular trap according to exemplary embodiments of the invention may be better understood with reference to the drawings and accompanying descriptions.

Before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details set forth in the following description or exemplified by the Examples. The invention is capable of other embodiments or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting.

Exemplary intravascular trap

Fig. la is a perspective view of an intravascular trap according to some exemplary embodiments of the invention indicated generally as 100.

Depicted exemplary trap 100 includes a proximal funnel 40 with a wide aperture 42 (ring 50) on the proximal side and a narrow aperture (46; Fig. lb) on the distal side and a particle filter 30 adapted to guide particles radially outward from the center of the filter during systole.

Also visible in Fig. la are insertion cannula70 and struts 80 and 82.

In some embodiments insertion cannula 70 is used to place trap 100 into a blood vessel through the wall of the vessel. Alternatively or additionally, in some embodiments struts 80 and/or 82 support flexible parts of trap 100. Fig. lb is an exploded view of the intravascular trap depicted in Fig. la which illustrates outer walls 34 of filter 30, connecting funnel 40 and filter 30 by means of a common ring at wide aperture 50. In some embodiments ring 50 defines a shape and/or size of hole 42. In some embodiments the ring which defines wide aperture 42 (ring 50) is constructed of a shape memory material (e.g. Nitinol). Alternatively or additionally, in some embodiments the ring 50 at wide aperture 42 applies force to an interior wall of a blood vessel to hold trap 100 in place. In the depicted embodiment when funnel 40 and filter 30 are assembled, the ring 50 at wide aperture 42 engages walls 34. In some embodiments narrow aperture 46 is also defined by a ring. In some embodiments the ring which defines narrow aperture 46 is constructed of a shape memory material (e.g. Nitinol). Alternatively or additionally, in some embodiments a diameter of narrow aperture 46 is narrower than a diameter wide aperture 42 (ring 50) by a factor of at least 2, at least 3, at least 4, at least 5 at least 6 or intermediate or larger factors. Alternatively or additionally, in some embodiments a distance between narrow aperture 46 and wide aperture 50(as measured along a line connecting their centers) is at least 0.3 mm, at least 3 mm, at least 5 mm, at least 10 mm, at least 15 mm, at least 20 mm, at least 25 mm, at least 30 mm or intermediate or greater distances. Alternatively or additionally, in some embodiments the distance between narrow aperture 46 and wide aperture 42 (ring 50) is less than 30 mm, lessthan25 mm, less than 20 mm, less than 15 mm, less than 10 mm, less than 7.5 mm, less than 5 mm, less than 3 mm, less than 0.3 mm or intermediate or lesser distances.

Alternatively or additionally, in some embodiments filter 30 of trap 100 includes a center region 36 which is convex towards its proximal side. The convex nature of center region 36 creates a circumferential trough 38 at the distal end of trap 30 in which trapped particles tend to collect during systole.

Alternatively or additionally, in some embodiments a distance "D" (Fig. 2a) between narrow aperture 46 and center region 36 is at least 0 mm, at least 1 mm at least 2 mm, at least 5 mm, at least 7.5 mm, at least 10 mm, at least 12.5 mm, at least 15 mm or intermediate or greater distances during systole.

Alternatively or additionally, in some embodiments a distance "D" (Fig. 2a) between narrow aperture 46 and center region 36is less than zero during systole, less than 1mm, less than 2 mm, less than 5 mm, less than 7.5 mm, less than 10 mm, less than 12.5 mm, less than 15 mm or intermediate or lesser distances. In some embodiments (not depicted) center region 36 protrudes through narrow aperture 46 into funnel 40.

In some embodiments trap 100 includes struts 85 (Fig. lb) adapted to support a portion of the trap.

For example, in some embodiments wide aperture 42 and/or narrow aperture 46 are supported by rings.

Alternatively or additionally, in some embodiments struts 82 are attached to walls 44 of funnel 40. In those embodiments which employ struts 82, they reduce a tendency of the funnel to invert during diastole. According to various exemplary embodiments of the invention attachment of struts 82 to walls 44 of funnel 40 is on an inner surface of walls 44 and/or on an outer surface of walls 44. Alternatively or additionally, attachment of struts 82 to walls 44 of funnel 40 is by gluing, sewing, heat welding, riveting or other methods.

Alternatively or additionally, in some embodiments struts 80 are attached to walls 34 of filter 30. In those embodiments which employ struts 80, they reduce a tendency of the filter to move towards funnel 40 during diastole. According to various exemplary embodiments of the invention attachment of struts 80 to walls 34 of filter 30 is on an inner surface of walls 34 and/or on an outer surface of walls 34. Alternatively or additionally, attachment of struts 80 to walls 34 of filter 30 is by gluing, sewing, heat welding, riveting or other methods. Alternatively or additionally, in some embodiments the struts 85 apply force to an interior wall of a blood vessel to hold trap 100 in place.

Alternatively or additionally, in some embodiments trap 100 includes cords 65 adapted to restrict changes in orientation between various parts of the trap.

In some embodiments cords 67 connect wide aperture 42 (ring 50) to center region 36 of filter 30. According to these embodiments, cords 67 restrict motion of center region 36 of filter 30 during systole. Alternatively or additionally, in some embodiments cords 68 connect a circumference of aperture 46 of funnel 40 to center region 36 of filter 30. According to these embodiments, cords 68 restrict motion of center region 36 of filter 30 during systole.

Exemplary use scenario

Fig. 2a is a schematic side view, indicated generally as 200, of an intravascular trap according to some exemplary embodiments of the invention deployed in a blood vessel 201 during systole. In the depicted embodiment a ring 50 installed at wide aperture 42 defines the shape/size of a hole 42 which conforms to the inner walls of blood vessel 201. Systolic blood flow is depicted by arrows 210, 211 and 212 for simplicity.

Particles following the path indicated by arrow 211 proceed through wide aperture 42 (ring 50) and narrow aperture 46 across distance "D" to center region 36 which deflects them to circumferential trough 38.

Particles following the path indicated by arrow 210 or 212 proceed through wide aperture 42 (ring 50) and strike an inner side of wall 44 which guides them to narrow aperture 46. The particles then proceed across distance "D" and find their way to circumferential trough 38.

As a result, particles accumulate in circumferential trough 38.

Fig. 2b is a schematic side view, indicated generally as 202, of an intravascular trap as in Fig. 2a deployed in blood vessel 201 during diastole. Diastolic blood flow is depicted by arrows 220, 221 and 222 for simplicity.

Arrow 221 proceeds through center region 36, across distance "D" through narrow aperture 46 and wide aperture without carrying any particles with it.

Arrows 220 and 222 pass through circumferential trough 38 where they move particles accumulated there towards an outer side of wall 44. These particles are deflected back towards an inner side of wall 34. The general flow direction causes them to accumulate in proximity to wide aperture 42 (ring 50) but outside wall 44 of the funnel.

In the next systolic cycle, these particles will be guided by walls 44 and 34 back to trough 38. This back and forth oscillation continues until the trap is removed. The probability that any particles will exit the trap via narrow aperture 46 is low. Any particles that do escape are likely to re-enter the trap in the next systolic cycle.

Exemplary assembly on catheter

Fig. 3 is a schematic side view of an exemplary assembly including a deployable intravascular trap according to an embodiment of the invention installed on a catheter depicted generally as 300.

In the drawing wide aperture 42 (ring 50) is connected to struts 320 mounted on catheter 310 and walls 34 and 44 are folded back along the catheter.

In some embodiments struts 320 are attached at one end to catheter 310 and are connected to ring 50 at the other end. Alternatively or additionally, in some embodiments struts 320 are constructed of a shape memory material (e.g. Nitinol).

Struts 320 support the shape of the trap and are the supporting part of the trap shape.

In some embodiments outer walls 34 of filter 30 are attached on one side to catheter 310 and on the other side are connected to ring 50.

In some embodiments walls 44 of funnel 40 are attached to ring 50.

During use catheter 310, with the intravascular trap assembled thereupon, is inserted via a peripheral blood vessel and guided to the target. In some embodiments catheter 310 also carries another device (e.g. stent or angioplasty balloon).

The catheter introduced to the vascular system at a location which may be remote from the point of operation the deployable trap is opened remotely from the point of operation and can be folded back to the catheter remotely from the point of operation.

At the end of the procedure the trap is retracted onto catheter 310 and removed. Exemplary materials

According to various exemplary embodiments of the invention walls 44 of funnel 40 and/or walls 34 of filter 30 and/or trough 38 of filter 30 and/or center region 36 of filter 40 are constructed of material made of polyurethane, PTFE or ePTFE with a pore size selected to allow blood flow through but restrict flow of debris or emboli floating in the body lumen or cavity. Pore size of from about 20 to about 300 microns, preferably from about 50 to about 150 microns

According to various exemplary embodiments of the invention cords 67 and/or 68 are constructed of thread made of nylon, polyester, PVDF or polypropylene having diameters from about 100 to about 1000 microns (e.g. common Surgical suture thread).

According to various exemplary embodiments of the invention struts 80 and/or 82 are constructed of shape memory material, such as Nitinol. According to various exemplary embodiments of the invention rings 50 and/or 46 are constructed of shape memory material, such as Nitinol

Exemplary parameters

According to exemplary embodiments of the invention the trap is engineered to withstand forces typically applied during systole and diastole. For example, a typical maximal force exerted on the trap during systole is about 1.6Kg. Alternatively or additionally, a typical maximum force exerted on the trap during diastole is about l .OKg.

According to various exemplary embodiments of the invention the diameter of wide aperture/ring 50 is in the range of 2 to 30 mm; 5 to 25 mm or 7 to 22 mm. Alternatively or additionally, according to various exemplary embodiments of the invention a total length of the trap is in the range of 5 to 50 mm; 10 to 40 mm or 20 to 30 mm.

Exemplary advantages

Exemplary trap 100 has no hinges so it is less prone to mechanical failure than many previously available alternatives. Alternatively or additionally, the simplicity of the described embodiments contributes to ease of folding, Ease of folding, in turn, contribute to simplification of trap insertion within the blood vessel the trap and by that to simplify the delivery of the trap to the blood vessel .

The trap has a unique design (shape).

It is expected that during the life of this patent many biocompatible materials and insertion techniques will be developed and the scope of the invention is includes all such new technologies a priori.

Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims.

Specifically, a variety of numerical indicators have been utilized. It should be understood that these numerical indicators could vary even further based upon a variety of engineering principles, materials, intended use and designs incorporated into the various embodiments of the invention. Additionally, components and/or actions ascribed to exemplary embodiments of the invention and depicted as a single unit may be divided into subunits. Conversely, components and/or actions ascribed to exemplary embodiments of the invention and depicted as sub-units/individual actions may be combined into a single unit/action with the described/depicted function.

Alternatively, or additionally, features used to describe a method can be used to characterize an apparatus and features used to describe an apparatus can be used to characterize a method. It should be further understood that the individual features described hereinabove can be combined in all possible combinations and sub-combinations to produce additional embodiments of the invention. The examples given above are exemplary in nature and are not intended to limit the scope of the invention which is defined solely by the following claims.

Each recitation of an embodiment of the invention that includes a specific feature, part, component, module or process is an explicit statement that additional embodiments of the invention not including the recited feature, part, component, module or process exist.

Specifically, the invention has been described in the context of cardiac surgery/ procedures but might also be used in other surgical procedures.

All publications, references, patents and patent applications mentioned in this specification are herein incorporated in their entirety by reference into the specification, to the same extent as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated herein by reference. In addition, citation or identification of any reference in this application shall not be construed as an admission that such reference is available as prior art to the present invention.

The terms "include", and "have" and their conjugates as used herein mean "including but not necessarily limited to".