Flow-reducing vascular implant

Abstract

A flow-reducing implant for reducing a rate of blood flow through a blood vessel is expandable in the blood vessel. The implant may include a balloon-expandable longitudinal portion and a shape-memory longitudinal portion forming a tapered shape at distal and / or proximal ends of the implant. An embolic device may be used to surround a throat of the implant to facilitate thrombus formation. A longitudinal end of the implant may be inhibited from expanding to maintain a tapered shape and expansion of the implant.

Description

Attorney Docket No. A0013430W001FLOW-REDUCING VASCULAR IMPLANTFIELD

[0001] The present technology is generally related to flow-reducing vascular implants, such as, but not limited to, a coronary sinus reducer.BACKGROUND

[0002] A flow-reducing implant is an implantable medical device that can be used in clinically appropriate situations to aid in the management of patients with severe angina symptoms refractory to optimal medical therapy and not amenable to further revascularization. One type of flow-reducing implant comprises a flow-reducing throat providing a restriction within the coronary sinus outflow with the intention of increasing the pressure and / or diverting flow for the purpose of driving higher perfusion to the capillary bed.SUMMARY

[0003] The techniques of this disclosure generally relate to flow-reducing implants, such as for a coronary sinus.

[0004] In one aspect, the present disclosure provides a flow-reducing implant for reducing a rate of blood flow through a blood vessel. The flow-reducing implant includes a balloon-expandable longitudinal portion having proximal and distal end segments. The balloon-expandable longitudinal portion is configured to plastically deform into an expanded configuration due to expansion of a balloon inside the balloon-expandable longitudinal portion. The flow-reducing implant further includes a shape-memory longitudinal portion coupled to and extending longitudinally from at least one of the proximal and distal end segments of the balloon-expandable longitudinal portion. The shape-memory longitudinal portion includes a pre-defined tapered segment configured to rebound to a tapered shape after being deformed.

[0005] In another aspect, the present disclosure provides a flow-reducing implant for reducing a rate of blood flow through a blood vessel. The flow-reducing implant includes a balloon-expandable longitudinal portion having first and second end portions. The flowreducing implant further includes first and second shape-memory longitudinal portions.1CORE / 3514225.010901 / 238815728.1Attorney Docket No. A0013430W001The first shape-memory longitudinal portion is coupled to the first end portion of the balloon-expandable longitudinal portion and extends outward longitudinally therefrom. The second shape-memory longitudinal portion is coupled to the second end portion of the balloon-expandable longitudinal portion and extends outward longitudinally therefrom. Each of the shape-memory portions are configured to contact the bodily lumen when the flow-reducing implant is in an expanded configuration such that a void is defined therebetween.

[0006] In yet another aspect, the present disclosure provides a flow-reducing implant for reducing a rate of blood flow through a blood vessel. The flow-reducing implant includes an implant body configurable between a collapsed configuration and an expanded configuration. The implant body has proximal and distal end portions and a throat portion therebetween when in the expanded configuration. The flow-reducing implant further includes an embolic device. Each of the end portions are configured to contact the blood vessel when the implant body is in the expanded configuration such that a void is defined between the blood vessel and the throat portion. The embolic device is configured to surround the throat portion of the implant body and fill the void to induce thrombosis.

[0007] In yet another aspect, the present disclosure provides a flow-reducing implant for reducing a rate of blood flow through a blood vessel. The flow-reducing implant includes a balloon-expandable longitudinal portion having a distal end portion and being configured to plastically deform into an expanded configuration due to expansion of a balloon therein. The flow-reducing implant further includes an over-molded longitudinal portion comprising a polymer material over-molded on the distal end portion of the balloon-expandable longitudinal portion. The over-molded longitudinal portion is configured to resist radial expansion. The balloon-expandable longitudinal portion is configured to induce endothelialization and anchor the flow-reducing implant within the blood vessel when in the expanded configuration. The over-molded longitudinal portion is configured to restrict the flow of blood through the blood vessel such that a backpressure is induced within the blood vessel following an implantation of the flow-reducing implant therein.

[0008] The details of one or more aspects of the disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and2CORE / 3514225.010901 / 238815728.1Attorney Docket No. A0013430W001advantages of the techniques described in this disclosure will be apparent from the description and drawings, and from the claims.BRIEF DESCRIPTION OF DRAWINGS

[0009] FIG. 1 A is a longitudinal section of an implanted flow-reducing implant according to an embodiment.

[0010] FIG. IB is a perspective view of the flow-reducing implant of FIG. 1 A

[0011] FIGS. 2A-2D are longitudinal sections depicting stages or steps of an implantation process for the flow-reducing implant of FIG. 1 A.

[0012] FIG. 3 A is a cross section of an implanted flow-reducing implant according to an embodiment.

[0013] FIG. 3B is similar to FIG. 3 A, but the flow-reducing implant is restricted.

[0014] FIG. 4A is a perspective view of the flow-reducing implant of FIG. 3 A.

[0015] FIG. 4B is a perspective view of the flow-reducing implant of FIG. 3B.

[0016] FIG. 5A is a longitudinal section of an implanted flow-reducing implant according to an embodiment.

[0017] FIG. 5B is a perspective view of the flow-reducing implant of FIG. 5 A.

[0018] FIG. 6A is a longitudinal section of an implanted flow-reducing implant according to an embodiment.

[0019] FIG. 6B is a perspective view of the flow-reducing implant of FIG. 6A.

[0020] FIG. 7A is a cross section of an implanted flow-reducing implant according to an embodiment.

[0021] FIG. 7B is a perspective view of the flow-reducing implant of FIG. 7A.

[0022] FIG. 8A is a longitudinal section of an implanted flow-reducing implant system according to an embodiment.

[0023] FIG. 8B is similar to FIG. 8A, but shows an alternative flow-reducing implant embodiment.

[0024] FIG. 8C is a perspective view of the flow-reducing implant of FIG. 8 A.

[0025] FIG. 9 is a front elevation of an embolic coil shown in FIGS. 8A and 8B.

[0026] FIG. 10A is a longitudinal section of an implanted flow-reducing implant according to an embodiment, and includes a balloon catheter.

[0027] FIG. 10B is similar to FIG. 10A, but does not include the balloon catheter.3CORE / 3514225.010901 / 238815728.1Attorney Docket No. A00I3430WO0I

[0028] FIG. 10C is a perspective view of the flow-reducing implant of FIG. 10B.

[0029] FIG. 11 A is a side elevation of another embodiment of a flow-reducing implant received on a balloon of a balloon catheter.

[0030] FIG. 1 IB is a longitudinal section of the flow-reducing implant of FIG. 11 A implanted in a blood vessel.DETAILED DESCRIPTION

[0031] Flow-reducing implant embodiments are described herein. Broadly, these embodiments can be categorized as self-expanding implants (i.e., implants having at least one shape-memory component to enable self-expansion), balloon-expandable implants (i.e., implants which are not self-expanding, and must therefore be expanded manually to plastically deform into a desired shape), or hybrid implants (i.e., implants that include shape-memory and balloon-expandable portions). As will be apparent from the following disclosure, it is believed these devices increase the safety of these devices and their implantation procedures. This is accomplished not only by reducing the probability of medical complications during an implantation procedure and thereafter, but by reducing the duration and complexity of the implantation procedure itself.

[0032] For the purpose of the present disclosure, the term "balloon-expandable" refers to components or materials configured to plastically deform into an expanded configuration due to expansion of a balloon therein. Implants having balloon-expandable portions are intended to be implanted into the body using a balloon catheter having a balloon which can be inflated in order to expand the balloon-expandable portion.

[0033] For the purpose of the present disclosure, the term "shape-memory" refers to components or materials configured to return to an original, pre-defined shape after being deformed. Returning to an original shape may be dependent on or caused by for example, temperature (e.g., a shape-memory material can return to its original shape when heated or cooled to a specific temperature, such as body temperature) or elastic properties (e.g., a shape-memory material can return to its original shape when an external compressive or tensile force is removed). In other words, unless specifically mentioned in certain embodiments, shape-memory and shape-memory materials include, but are not limited to,4CORE / 3514225.010901 / 238815728.1Attorney Docket No. A0013430W001materials that return to their original, predefined shape upon application of a stimulus, such as temperature.

[0034] Referring to FIGS. 1 A and IB, one embodiment of a flow-reducing implant is generally indicated at reference numeral 100. FIG. lAis a longitudinal section depicting the flow-reducing implant 100 received on a balloon 102 of a balloon catheter, generally indicated at 104, with the balloon and the implant in their expanded configurations within a blood vessel 106. FIG. IB is a perspective depicting the expanded flow-reducing implant 100 implanted in the blood vessel 106 with the balloon catheter 104 removed.

[0035] Referring still to FIGS. 1 A and IB, the illustrated implant 100 generally comprises a balloon-expandable longitudinal portion, generally indicated at 108, and a shape-memory longitudinal portion, generally indicated at 110, and is configured (i.e., designed and constructed) to be implanted in the blood vessel 106, as shown. The shapememory longitudinal portion 110 is coupled to the balloon-expandable longitudinal portion 108 at a distal end segment 112 thereof (though in other embodiments it may be coupled to a proximal segment of the balloon-expandable longitudinal portion). In the illustrated embodiment, the balloon-expandable longitudinal portion 108 has a length greater than that of the shape-memory longitudinal portion 110, which facilitates anchoring of the flow-reducing implant 100 on the blood vessel wall 106 during balloon expansion.

[0036] The balloon-expandable longitudinal portion 108 has a body segment 114 and a distal segment 112. The body segment 114 is configured to expand and plastically deform into a cylindrical shape by expansion of the balloon 102, and the distal end segment 112 is configured to expand and plastically deform into a tapered or cone shape by expansion of the balloon. The distal or cone-shaped segment 112 tapers distally to a distal end of the balloon-expandable longitudinal portion 108. The balloon-expandable longitudinal portion 108 may be generally in the form of a vascular stent, known in the art, including one or more interconnected struts 116 forming a mesh-like tube enabling radial expansion and configured to maintain its expanded shape. The struts 116 may be formed from metal, for example, stainless steel or cobalt chromium alloy, or other suitable material. The balloon-expandable longitudinal portion 108 may be of other designs suitable for balloon expansion and plastic deformation in its expanded configuration.5CORE / 3514225.010901 / 238815728.1Attorney Docket No. A0013430W001

[0037] The shape-memory longitudinal portion 110 has a proximal segment 118 coupled to the distal end of the of the balloon-expandable longitudinal portion. In its original, non-deformed configuration, as shown in FIGS. lAand IB, the proximal segment 118 flares distally away from the distal end of the balloon-expandable longitudinal portion 108 (or, described another way, tapers proximally toward the distal end of the balloon-expandable longitudinal portion) to form a cone shape, which may be a mirror-image of the distal end segment 112 of the balloon-expandable longitudinal portion. Together, the distal end segment 112 of the balloon-expandable longitudinal portion 108 and the proximal segment 118 of the shape-memory longitudinal portion 110 have an hourglass shape. The illustrated shape-memory longitudinal portion 110 also include a distal segment 120, which in its original, non-deformed configuration is generally cylindrical and configured to engage the blood vessel 106.

[0038] A throat 122 is defined at the juncture of the hourglass shape of the two segments (i.e., the distal end segment 112 of the balloon-expandable longitudinal portion 108 and the proximal segment 118 of the shape-memory longitudinal portion 110). After implantation and endothelialization of the implant in the blood vessel 106, the inner diameter (ID) at the throat 122 reduces the rate of blood flow through the vessel. After endothelialization, the inner diameter ID of the throat 122 is substantially determinative of the rate of flow through the blood vessel 106.

[0039] Referring to FIGS. 2A-2D, a flow-reducing implant according to another embodiment is generally indicated at reference number 200. FIGS. 2A-2D show the flowreducing implant 200 being installed in stages (e.g., four stages) using a balloon catheter, generally indicated at 202, having a sheath 204, a balloon 206, an inflation lumen 208, and a push tube 210. The stages of implantation shown in FIGS. 2A-2D are generally indicated at reference numbers 200A-200D, respectively. The flow-reducing implant 200 is configured (i.e., designed and constructed) to be implanted in a blood vessel 216, as shown. Flow-reducing implant 200 generally comprises a balloon-expandable longitudinal portion, generally indicated at 212, and a shape-memory longitudinal portion, generally indicated at 214. The shape-memory longitudinal portion 214 is coupled to the balloon-expandable longitudinal portion 212 at a proximal end segment 220 thereof. In the illustrated embodiment, the balloon-expandable longitudinal portion 212 has a length greater than that of the shape-memory longitudinal portion 214, which facilitates6CORE / 3514225.010901 / 238815728.1Attorney Docket No. A0013430W001anchoring of the flow-reducing implant 200 in the blood vessel 216 during balloon expansion, promotes endothelialization, and prevents migration of the flow-reducing implant 200 during retraction of the balloon catheter 202 (e.g., withdrawing the catheter longitudinally proximally).

[0040] As seen best in FIG. 2D, like flow-reducing implant 100, flow-reducing implant 200 includes a throat 222 defined at the juncture of the hourglass shape of the proximal end segment 220 of the balloon-expandable longitudinal portion 212 and a distal segment 224 of the shape-memory longitudinal portion 214. After implantation and endothelialization of the implant in the blood vessel 216, the inner diameter (ID) at the throat 222 reduces the rate of blood flow through the blood vessel. The inner diameter ID of the throat 222 is substantially determinative of the rate of flow through the blood vessel 216, and may be adjusted depending on the needs of the individual receiving the flowreducing implant 200. Also determinative of the rate of blood flow through the blood vessel 216 is the geometry of the shape-memory longitudinal portion 214. For example, the illustrated embodiment of FIG. IB shows the shape-memory longitudinal portion 110 comprising a mesh-like geometry and having a plurality of apertures thereacross; the size and shape of such apertures may be manipulated during the manufacture of the flowreducing implant 100 in order to increase or reduce the rate at which blood flows therethrough (e.g., through the proximal segment 118 thereof).

[0041] Referring to FIG. 2A, at step 200A, the flow-reducing implant 200 is inserted into the blood vessel 216 and located at the desired implantation site (e.g., coronary sinus). The flow-reducing implant 200 is at an axial location with respect to the blood vessel 216 and is aligned therewith (i.e., the catheter 202 and flow-reducing implant are coaxial with the longitudinal axis LA). The balloon-expandable longitudinal portion 212 of the flowreducing implant 200 extends outside the end of the sheath 204, as does a portion of the balloon 206.

[0042] Referring to FIG. 2B, at step 200B, the balloon 206 is inflated using fluid (e.g., saline) delivered thereto via the inflation lumen 208, such that the balloon-expandable longitudinal portion 212 is expanded and comes into contact with the vessel wall 218. The balloon 206 is moved forward (e.g., distally) prior to inflation so that it is aligned with the flow-reducing implant 200. The geometry of the balloon 206 corresponds to the interior geometry of the balloon-expandable longitudinal portion 212 in the expanded7CORE / 3514225.010901 / 238815728.1Attorney Docket No. A0013430W001configuration, such that expansion of the balloon 206 distributes pressure evenly across thereon. The proximal end segment 220 of the balloon-expandable longitudinal portion 212 is expanded as well.

[0043] Referring to FIG. 2C, at step 200C, the balloon 206 is deflated and collapsed to a position entirely within the sheath 204. Because the shape-memory longitudinal portion 214 is still wedged between the sheath 204 and the push tube 210, the balloon 206 can be retracted to a position within the sheath without moving the flow-reducing implant 200 (namely the balloon-expandable longitudinal portion) longitudinally within the blood vessel 216. Inhibiting movement or migration of the flow-reducing implant 200 after its expansion promotes endothelialization.

[0044] Referring to FIG. 2D, at step 200D, the sheath 204 is retracted (e.g., withdrawn longitudinally proximally) such that the flow-reducing implant 200 is released from the catheter 202 entirely, and the shape-memory longitudinal portion 214 is free to expand to its non-deformed shape.

[0045] FIG. 2D shows the shape-memory longitudinal portion 214 fully expanded, but expansion may take a certain amount of time to occur. In the illustrated embodiment, the shape-memory longitudinal portion 214 may be temperature dependent, and returns to its original (i.e., expanded) shape as it approaches body temperature (e.g., when the shapememory longitudinal portion is constructed using a nickel -titanium alloy). In another embodiment, the shape-memory longitudinal portion 214 may be expanded by elastically rebounding from its collapsed configuration (e.g., when the shape-memory longitudinal portion is constructed using spun polytetrafluoroethylene).

[0046] It is envisioned that the flow-reducing implants 100 and 200, along with the disclosed method of implantation, may offer several advantages over existing systems and methods. Namely, a reduction in the complexity of removing the device if necessary, a reduction in the risk of implant dislodgement, and / or the creation of an immediate or near immediate backpressure upon implantation. Flow-reducing implant 100 also provides for adjustments in flow reduction via alterations to the throat diameter, as well as the ability to use a finer mesh on the proximal self-expanding portion of the stent.

[0047] Referring now to FIGS. 3A-4B, another flow-reducing implant according to an embodiment of the present disclosure is disclosed, and generally indicated at reference number 300. Like the flow-reducing implant 100 of FIGS. 1 and 2, flow-reducing implant8CORE / 3514225.010901 / 238815728.1Attorney Docket No. A0013430W001300 includes a balloon-expandable longitudinal portion 302 and a shape-memory longitudinal portion 304. In the illustrated embodiment, the shape-memory longitudinal portion 304 is coupled to the balloon-expandable longitudinal portion 302 at a distal end segment 306 of the balloon-expandable longitudinal portion; however, it may be coupled at either the distal segment or a proximal end segment 308. FIGS. 3 A and 4A show flowreducing implant 300 in an expanded configuration prior to rebounding of the shapememory longitudinal portion 304, meaning that flow-reducing implant 300 has been implanted, but the shape-memory longitudinal portion has not yet returned to its original shape. FIG. 3B and 4B show flow-reducing implant 300 after the shape-memory longitudinal portion 304 has rebounded. The balloon-expandable longitudinal portion 302 may be constructed as a stent, such as described above with respect to FIGS. 1 A and IB (e.g., a bare metal stent), configured to anchor flow-reducing implant 300 to the blood vessel 310 at the wall thereof such that the implant does not shift longitudinally therein.

[0048] Flow-reducing implant 300 has a first lumen 314 within the shape-memory longitudinal portion 304 and a second lumen 316 within the balloon-expandable longitudinal portion 302. Following the implantation of flow-reducing implant 300 (e.g., after the balloon-expandable longitudinal portion 302 has been expanded and the balloon removed), the shape-memory longitudinal portion 304 is configured to retract. By retracting, the first lumen 314 narrows, in turn reducing the rate of blood flow therethrough.

[0049] Flow-reducing implant 300 can be delivered using existing techniques, so an operator (e.g., a medical professional such as a surgeon) is not required to learn new skills in order to use it. Additionally, because the shape-memory longitudinal portion 304 contracts shortly after implantation of flow-reducing implant 300, there is an instantaneous or near-instantaneous backpressure induced in the blood vessel 310. It is believed the complexity of removing the balloon with which flow-reducing implant 300 is installed is also significantly reduced, as the device maintains an open internal geometry until the balloon is removed. Flow-reducing implant 300 can also be re-opened if needed for subsequent procedures, wherein the shape-memory longitudinal portion 304 narrows again automatically.

[0050] Referring now to FIGS. 5A and 5B, another flow-reducing implant according to an embodiment of the present disclosure is shown, and is generally indicated at9CORE / 3514225.010901 / 238815728.1Attorney Docket No. A0013430W001reference number 500. Flow-reducing implant 500 generally comprises first, second, and third shape-memory hoops 502, 504, 506, respectively, spaced apart longitudinally along the length of implant. Each of the shape-memory hoops 502, 504, 506 are coupled by a graft material 509 configured to at least partially restrict the flow of blood therethrough. For the purposes of the present disclosure, the term "graft material" refers to materials (e.g., fabric) which are at least partially impervious to blood. Graft materials will most frequently be referred to with respect to their use as a layer or covering for redirecting and / or restricting the flow of blood. Such materials are commonly used as graft materials in stent-grafts, which are known in the art. The graft material may be synthetic, such as woven polyester or expanded PTFE.

[0051] Flow-reducing implant 500 has a collapsed configuration (wherein each of the shape-memory hoops 502, 504, 506 are collapsed) and an expanded configuration (wherein each of the shape-memory hoops are expanded). FIGS. 5 A and 5B show flowreducing implant 500 in the expanded configuration. When in the expanded configuration, the first and third shape-memory hoops 502, 506, located at end segments 508 of flowreducing implant 500, have a substantially similar diameter which is approximately equal to (e.g., slightly larger than) the diameter of the blood vessel 510 in which it is implanted. The second shape-memory hoop 504 has a diameter less than the first and third shape memory hoops 502, 506, such that a throat 512 is defined therebetween. When in the collapsed configuration, each of the shape-memory hoops 502, 504, 506 has a reduced diameter with respect to their diameters when in the expanded configuration. Additionally, the shape memory hoops 502, 504, 506 may be substantially elliptic when in the collapsed configuration such that they may be laid down within a catheter sheath of minimal diameter. This reduces the footprint of the catheter needed to deliver flow-reducing implant 500, thereby reducing the invasiveness of its implantation.

[0052] Because movement of flow-reducing implant 500 from the collapsed configuration (e.g., compressed within a catheter sheath) to the expanded configuration (e.g., implanted) is accomplished automatically, a balloon is not necessary for its installation. This may offer several advantages over existing systems, such as a simpler, safer, and faster implantation procedure.

[0053] In alternative embodiments, the flow-reducing implant 500 may include a central balloon-expandable portion in place of the second shape-memory hoop 504. In this10CORE / 3514225.010901 / 238815728.1Attorney Docket No. A0013430W001embodiment, the balloon-expandable portion has a diameter similar to that of the aforementioned second shape-memory hoop (e.g., a reduced diameter) such that blood flow is restricted and a backpressure induced. Because the shape-memory hoops at the end segments of flow-reducing implant 500 expand automatically, a straight balloon can be used to expand the balloon-expandable portion therebetween. The balloon-expandable portion can be adjusted after implantation of the device, allowing for observations of device performance to inform subsequent device adjustments.

[0054] Referring to FIGS. 6A and 6B, another flow-reducing implant according to an embodiment of the present disclosure is shown, and is generally indicated at reference number 600. Flow-reducing implant 600 is a self-expanding implant with a substantially conical geometry.

[0055] Flow-reducing implant 600 generally comprises first and second shapememory hoops 602, 604, respectively, a graft material therebetween, a plurality of arms 606 on the second shape-memory hoop. The flow-reducing implant 600 is configured to have an expanded configuration, and a collapsed configuration. When in the expanded configuration, the first shape-memory hoop 602 has a diameter approximately equal to (e.g., slightly larger than) the diameter of a blood vessel 608 in which it is inserted, and the second shape-memory hoop 604 has a smaller or reduced diameter RD (e.g., less than the diameter of the first shape-memory hoop). The arms 606 extend transversely outward from the second hoop 604, and are spaced apart radially thereon.

[0056] When in the collapsed configuration, each of the shape-memory hoops 602, 604 have a reduced diameter (not shown) compared to their diameters when in the expanded configuration. Additionally, the shape memory hoops 602, 604 may be substantially elliptic when in the collapsed configuration such that they may be laid down or flattened within a catheter sheath of minimal diameter. The arms 606 are configured to fold inward (i.e., toward a position parallel with the longitudinal axis LA) so that they may be maintained in the catheter sheath as well. These features reduce the footprint of the catheter needed to deliver flow-reducing implant 600, thereby reducing the invasiveness of its implantation.

[0057] After the flow-reducing implant 600 is delivered to the blood vessel 608, it is configured to automatically expand such that the first shape-memory hoop 602 contacts an inner wall 610 of the blood vessel, and the plurality of arms 606 extend outwardly to11CORE / 3514225.010901 / 238815728.1Attorney Docket No. A0013430W001anchor the device thereto. Flow-reducing implant 600 has a reduced footprint when compared to existing systems.

[0058] Referring now to FIGS. 7A and 7B, another flow-reducing implant according to an embodiment of the present disclosure is shown, and is generally indicated at reference number 700. Flow-reducing implant 700 comprises two end sections, each generally indicated at 702, and a center section, generally indicated at 704 therebetween. The flow-reducing implant 700 is configurable between a collapsed configuration and an extended configuration. The two end sections 702 may be formed from a sinusoidal wire or weld pattern, for example. The center section 704 is formed from the sinusoidal wire 706, for example, having a second weld pattern 710 that is different from the first weld pattern 708. The different weld patterns 708, 710 exhibit different capacities to withstand internal, radial pressure from within the flow-reducing implant 700 that impart radial deformation to the sections 704, 702. In this way, each section (i.e., center section 704 and end sections 702) can be tailored to expand to a predetermined diameter (or internal cross-sectional area) at a desired pressure. This is particularly useful when used in conjunction with a semi-compliant balloon.

[0059] In the collapsed configuration, each section (i.e., the two end sections 702 and the center section 704) has a substantially similar inner diameter, such that the flowreducing implant 700 has a cylindrical geometry. In the expanded configuration, each of the end sections 702 taper from a large diameter at the end segments (e.g., a diameter approximately equal to or slightly greater than the vessel diameter) to a reduced diameter RD where they join with the center section. The taper may be linear as illustrated, but may also be curved or other shapes. The center section 704 can be expanded to have a diameter of any value between its collapsed diameter and the diameter of a blood vessel 712 in which the flow-reducing implant 700 is implanted.

[0060] Referring now to FIGS. 8A-8C, a flow-reducing implant system is shown, as well as a variant of flow-reducing implant system (FIG. 8B; corresponding reference numbers are labeled similarly). The flow-reducing implant system generally includes a flow-reducing implant 800, 800' which may be similar to existing flow-reducing implants in that it has two expandable portions on opposite end segments 802, 802' (e.g., proximal and distal end segments) of the implant configured to expand and having a narrowed throat 804, 804' therebetween (e.g., a throat segment), thereby forming an hourglass shape.12CORE / 3514225.010901 / 238815728.1Attorney Docket No. A0013430W001In addition, flow-reducing implant system includes one or more embolic coils 806, 806' (broadly, embolic device(s)) disposed around (e.g., circumferentially about) the throat 804, 804'. Referring to FIG. 9, an enlarged example of an embolic coil 806, 806' is shown. The embolic coil includes a plurality of fiber enlacements 807 located thereon for enhancing thrombus generation. When implanted, the embolic coil(s) 806, 806' are received in and at least partially fill an open space or void 808, 808' defined between the blood vessel 810, 810' and the throat 804, 804' of the implant 800, 800'. This is depicted in FIGS. 8A and 8B, showing embolic coils 806, 806' in the void 808, 808'. While the illustrations depict the coils 806, 806' as being present only above and below the throat 804, 804', this is simply for ease of understanding with respect to illustration; the coils are located circumferentially around the throat such that a substantially uniform distribution thereof is found throughout the void.

[0061] The embolic coils 806, 806' are configured to block blood flow and induce generate thrombosis in the area where they are deposited (e.g., within the void 808, 808'). By locating embolic coils 806, 806' within the void 808, 808' and around the throat 804, 804' of the flow-reducing implant 800, 800', thrombus fills the void, increasing the implants' flow-reducing properties by reducing the diameter of the blood vessel 810 in the area around the void. In one or more embodiments, such as shown in FIG. 8B, graft material 820 may be included on flow-reducing implant 800' to further restrict the flow of blood through the reduced-diameter RD lumen defined by the throat 804'.

[0062] An exemplary method of impaling the flow-reducing implant system of FIGS.8A-8C will now be described. Two guidewires (e.g., a first guidewire and a second guidewire) may be deployed distal of the intended delivery site. The flow-reducing implant is received in a sheath catheter, which is delivered to the target site using the first guidewire. Once positioned at the treatment site (e.g., within the coronary sinus) the sheath is partially collapsed to expand the distal portion 802, 802' of the flow-reducing implant 800, 800' such that the reduced-diameter lumen defined by the throat segment 804, 804' and the proximal expandable portion of the flow-reducing implant are still in the sheath. The embolic coil 806, 806' is delivered — using the second guidewire and / or catheter — past the non-expanded proximal portion to the throat 804, 804'. The embolic coil 806, 806' is then deployed around the throat 804, 804'. The expanded distal portion 802' inhibits the embolic coil(s) 806', from moving distally past the implant 800, 800'. The13CORE / 3514225.010901 / 238815728.1Attorney Docket No. A0013430W001sheath is then retracted to enable expansion of the proximal portion 802, 802' of the implant, thereby capturing the embolic coil(s) 806, 806' around the throat segment 804, 804' and in the void 808, 808'.

[0063] Another flow-reducing implant is shown at FIGS. 10A-10C, and is generally indicated at reference number 1000. The flow-reducing implant 1000 is configurable between a collapsed configuration and an expanded configuration. The flow-reducing implant includes a first (e.g., distal) end segment 1002, and a second (e.g., proximal) end segment 1004. Flow-reducing implant 1000 is a balloon-expandable implant, and is configured to be delivered to and expanded within a blood vessel 1006 via a balloon catheter 1008 having a balloon 1010. In the illustrated embodiment, the first end segment 1002 has a substantially conical geometry when in the expanded configuration, while the second end segment 1004 has a substantially cylindrical geometry when in the expanded configuration. The first end segment 1002 defines a first lumen 1012 and the second end segment defines a second lumen 1014, the first lumen having a reduced diameter RD which is less than a diameter of the second lumen. The first end segment 1002 is configured to restrict the flow of blood through the flow-reducing implant 1000.

[0064] Flow-reducing implant 1000 can be delivered using existing techniques, so an operator is not required to learn new skills in order to use it. Additionally, because the first end segment 1002 has a substantially conical shape immediately after expansion thereof, there is an instantaneous or near-instantaneous backpressure induced in the blood vessel 1006.

[0065] Referring to FIGS. 11 A and 1 IB, another embodiment of a flow-reducing implant is generally indicated at reference numeral 1100. The flow-reducing implant 1100 is configurable between a collapsed configuration (FIG. 11 A) and an expanded configuration (FIG. 11B). The implant 1100 includes a balloon-expandable longitudinal portion or body portion 1104 and a distal end portion 1102. The balloon-expandable longitudinal portion 1104 is configured to plastically deform into an expanded configuration due to expansion of a balloon 1110 therein. The balloon-expandable longitudinal portion 1104 is configured to induce endothelialization and anchor the flowreducing implant 1100 within the blood vessel when in the expanded configuration. The distal end portion 1102 includes polymer material over-molded thereon that is configured to resist radial expansion, particularly when the balloon-expandable longitudinal portion is14CORE / 3514225.010901 / 238815728.1Attorney Docket No. A0013430W001expanding due to expansion of an internal balloon. Accordingly, the over-molded distal end portion is configured to restrict the flow of blood through the blood vessel such that a backpressure is induced within the blood vessel following an implantation of the flowreducing implant 1100 therein. The polymer material and its shape on the distal end (e.g., tapering, blunt shape) may be atraumatic to inhibit vessel trauma when tracking through the blood vessel. Suitable, non-limiting examples of materials include polyesters, polyamides, polyether block amides, and combinations thereof, including blends.

[0066] The flow-reducing implant 1100 can be delivered using existing techniques, so an operator is not required to learn new skills in order to use it. Additionally, because the over-molded distal end section 1102 has a reduced interior area or cross-sectional dimensional immediately after expansion of the body portion 1104 due to the polymer restricting expansion, there is an instantaneous or near-instantaneous backpressure induced in the blood vessel 1106.

[0067] While the systems and methods above have been described and disclosed in certain terms and have disclosed certain embodiments or modifications, persons skilled in the art who have acquainted themselves with the disclosure, will appreciate that it is not necessarily limited by such terms, nor to the specific embodiments and modification disclosed herein. Thus, a wide variety of alternatives, suggested by the teachings herein, can be practiced without departing from the spirit of the disclosure, and rights to such alternatives are particularly reserved and considered within the scope of the disclosure.

[0068] Not all of the depicted components illustrated or described may be required. In addition, some implementations and embodiments may include additional components. Variations in the arrangement and type of the components may be made without departing from the spirit or scope of the claims as set forth herein. Additional, different or fewer components may be provided and components may be combined. Alternatively, or in addition, a component may be implemented by several components.

[0069] The above description illustrates embodiments by way of example and not by way of limitation. This description enables one skilled in the art to make and use aspects of the invention, and describes several embodiments, adaptations, variations, alternatives and uses of the aspects of the invention, including what is presently believed to be the best mode of carrying out the aspects of the invention. Additionally, it is to be understood that the aspects of the invention are not limited in its application to the details of construction15CORE / 3514225.010901 / 238815728.1Attorney Docket No. A0013430W001and the arrangement of components set forth in the following description or illustrated in the drawings. The aspects of the invention are capable of other embodiments and of being practiced or carried out in various ways. Also, it will be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.

[0070] It will be apparent that modifications and variations are possible without departing from the scope of the invention defined in the appended claims. As various changes could be made in the above constructions and methods without departing from the scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

[0071] In view of the above, it will be seen that several advantages of the aspects of the invention are achieved and other advantageous results attained.

[0072] The invention may be further described by reference to the following numbered paragraphs:1. A flow-reducing implant for reducing a rate of blood flow through a blood vessel, comprising: a balloon-expandable longitudinal portion having proximal and distal end segments, wherein the balloon-expandable longitudinal portion is configured to plastically deform into an expanded configuration due to expansion of a balloon inside the balloon-expandable longitudinal portion; and a shape-memory longitudinal portion coupled to and extending longitudinally from at least one of the proximal and distal end segments of the balloon-expandable longitudinal portion, wherein the shape-memory longitudinal portion includes a pre-defined tapered segment configured to rebound to a tapered shaped after being deformed.2. The flow-reducing implant set forth in paragraph 1, wherein the shapememory longitudinal portion is coupled to the distal end segment of the balloonexpandable longitudinal portion, and wherein the pre-defined tapered segment is configured to retract in cross section to its tapered shape after delivery of the flowreducing implant into the blood vessel.3. The flow-reducing implant set forth in any one of paragraphs 1 or 2, wherein the shape-memory longitudinal portion is further configured to reduce blood flow16CORE / 3514225.010901 / 238815728.1Attorney Docket No. A0013430W001through the blood vessel due the pre-defined tapered segment, such that a backpressure is induced within the blood vessel after implantation of the flow-reducing implant.4. The flow-reducing implant of paragraph 1, wherein the pre-defined tapered segment of the shape-memory longitudinal portion is coupled to the distal end segment of the balloon-expandable longitudinal portion.5. The flow-reducing implant of paragraph 4, wherein the pre-defined tapered segment of the shape-memory longitudinal portion is configured to expand and flare distally away from the distal end segment of the balloon-expandable longitudinal portion.6. The flow-reducing implant of any one of paragraphs 4 or 5, wherein the distal end segment of the balloon-expandable longitudinal portion tapers distally toward the pre-defined tapered segment of the shape-memory longitudinal portion.7. The flow-reducing implant of any one of paragraphs 4-6, wherein a juncture of the distal end segment of the balloon-expandable longitudinal portion and the pre-defined tapered segment of the shape-memory longitudinal portion defines a throat of the flow-reducing implant.8. The flow-reducing implant of any one of paragraphs 4-7, wherein the balloon-expandable longitudinal portion include a body segment extending proximal of the distal end segment is configured to engage the blood vessel when expanded by a balloon.9. The flow-reducing implant set forth in paragraph 8, wherein the body segment has a length greater than a length of the shape-memory longitudinal portion.10. The flow-reducing implant of paragraph 1, wherein the pre-defined tapered segment of the shape-memory longitudinal portion is coupled to the proximal end segment of the balloon-expandable longitudinal portion.11. The flow-reducing implant of paragraph 10, wherein the pre-defined tapered segment of the shape-memory longitudinal portion is configured to expand and flare proximally away from the proximal end segment of the balloon-expandable longitudinal portion.12. The flow reducing implant set forth in any one of paragraphs 10 or 11, wherein the proximal end segment of the balloon-expandable longitudinal portion flares distally away from the distal end segment of the shape-memory longitudinal portion.17CORE / 3514225.010901 / 238815728.1Attorney Docket No. A0013430W00113. The flow-reducing implant of any one of paragraphs 10-12, wherein a juncture of the proximal end segment of the balloon-expandable longitudinal portion and the pre-defined tapered segment of the shape-memory longitudinal portion defines a throat of the flow-reducing implant.14. The flow-reducing implant of paragraph 4, wherein the shape-memory longitudinal portion and the balloon-expandable longitudinal portion are configured to form an hourglass shape when the shape-memory longitudinal portion is expanded, and wherein the balloon-expandable longitudinal portion is configured to promote an endothelialization response when in the expanded configuration.15. A flow-reducing implant for reducing a rate of blood flow through a blood vessel, comprising: a balloon-expandable longitudinal portion having first and second end portions; first and second shape-memory longitudinal portions; wherein the first shapememory longitudinal portion is coupled to the first end portion of the balloon-expandable longitudinal portion and extends outward longitudinally therefrom; wherein the second shape-memory longitudinal portion is coupled to the second end portion of the balloonexpandable longitudinal portion and extends outward longitudinally therefrom; and wherein each of the shape-memory portions are configured to contact the bodily lumen when the flow-reducing implant is in an expanded configuration such that a void is defined therebetween.16. A flow-reducing implant for reducing a rate of blood flow through a blood vessel, comprising: an implant body configurable between a collapsed configuration and an expanded configuration, wherein the implant body has proximal and distal end portions and a throat portion therebetween when in the expanded configuration; andan embolic device, wherein each of the end portions are configured to contact the blood vessel when the implant body is in the expanded configuration such that a void is defined between the blood vessel and the throat portion, wherein the embolic device is configured to surround the throat portion of the implant body and fill the void to induce thrombosis.17. The flow-reducing implant set forth in paragraph 16, wherein the embolic device comprises an embolic coil.18. A method of reducing a rate of blood flow through a blood vessel, the method comprising: inserting a flow-reducing implant into the blood vessel using a balloon catheter, the flow-reducing implant comprising: a balloon-expandable longitudinal18CORE / 3514225.010901 / 238815728.1Attorney Docket No. A0013430W001portion having proximal and distal end portions and a throat portion therebetween, wherein the balloon-expandable longitudinal portion is configured to plastically deform into an expanded configuration due to expansion of the balloon therein; wherein each of the end portions are configured to contact blood vessel when the flow-reducing implant is in the expanded configuration such that a void is defined therebetween around the throat portion; expanding the distal end portion of the balloon-expandable longitudinal portion by inflating the balloon therein; inserting an embolic coil around the throat portion; and expanding the proximal end portion of the balloon-expandable longitudinal portion by inflating the balloon therein, wherein the embolic coil is maintained in the void after the proximal end portion is expanded such that the embolic coil induces the formation of thrombus in the void.19. A flow-reducing implant for reducing a rate of blood flow through a blood vessel, the flow-reducing implant comprising: a balloon-expandable longitudinal portion having a distal end portion and being configured to plastically deform into an expanded configuration due to expansion of a balloon therein; and an over-molded longitudinal portion comprising a polymer material over-molded on the distal end portion of the balloon-expandable longitudinal portion, wherein the over-molded longitudinal portion is configured to resist radial expansion; wherein the balloon-expandable longitudinal portion is configured to induce endothelialization and anchor the flow-reducing implant within the blood vessel when in the expanded configuration; wherein the over-molded longitudinal portion is configured to restrict the flow of blood through the blood vessel such that a backpressure is induced within the blood vessel following an implantation of the flowreducing implant therein.20. The flow-reducing implant set forth in paragraph 19, wherein the overmolded longitudinal portion is atraumatic for blood vessel tracking.

[0073] It should be understood that various aspects disclosed herein may be combined in different combinations than the combinations specifically presented in the description and accompanying drawings. It should also be understood that, depending on the example, certain acts or events of any of the processes or methods described herein may be performed in a different sequence, may be added, merged, or left out altogether (e.g., all described acts or events may not be necessary to carry out the techniques). In addition, while certain aspects of this disclosure are described as being performed by a single19CORE / 3514225.010901 / 238815728.1Attorney Docket No. A0013430W001module or unit for purposes of clarity, it should be understood that the techniques of this disclosure may be performed by a combination of units or modules associated with, for example, a medical device.

[0074] In one or more examples, the described techniques may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored as one or more instructions or code on a computer-readable medium and executed by a hardware-based processing unit. Computer-readable media may include non-transitory computer-readable media, which corresponds to a tangible medium such as data storage media (e.g., RAM, ROM, EEPROM, flash memory, or any other medium that can be used to store desired program code in the form of instructions or data structures and that can be accessed by a computer).

[0075] Instructions may be executed by one or more processors, such as one or more digital signal processors (DSPs), general purpose microprocessors, application specific integrated circuits (ASICs), field programmable logic arrays (FPGAs), or other equivalent integrated or discrete logic circuitry. Accordingly, the term “processor” as used herein may refer to any of the foregoing structure or any other physical structure suitable for implementation of the described techniques. Also, the techniques could be fully implemented in one or more circuits or logic elements.CORE / 3514225.010901 / 238815728.1

Claims

Attorney Docket No. A0013430W001WHAT IS CLAIMED IS:

1. A flow-reducing implant for reducing a rate of blood flow through a blood vessel, comprising:a balloon-expandable longitudinal portion having proximal and distal end segments, wherein the balloon-expandable longitudinal portion is configured to plastically deform into an expanded configuration due to expansion of a balloon inside the balloonexpandable longitudinal portion; anda shape-memory longitudinal portion coupled to and extending longitudinally from at least one of the proximal and distal end segments of the balloon-expandable longitudinal portion, wherein the shape-memory longitudinal portion includes a predefined tapered segment configured to rebound to a tapered shaped after being deformed.

2. The flow-reducing implant set forth in claim 1, wherein the shape-memory longitudinal portion is coupled to the distal end segment of the balloon-expandable longitudinal portion, and wherein the pre-defined tapered segment is configured to retract in cross section to its tapered shape after delivery of the flow-reducing implant into the blood vessel.

3. The flow-reducing implant set forth in any one of claims 1 or 2, wherein the shape-memory longitudinal portion is further configured to reduce blood flow through the blood vessel due the pre-defined tapered segment, such that a backpressure is induced within the blood vessel after implantation of the flow-reducing implant.

4. The flow-reducing implant set forth in claim 1, wherein the pre-defined tapered segment of the shape-memory longitudinal portion is coupled to the distal end segment of the balloon-expandable longitudinal portion.

5. The flow-reducing implant of claim 4, wherein the pre-defined tapered segment of the shape-memory longitudinal portion is configured to expand and flare distally away from the distal end segment of the balloon-expandable longitudinal portion.21CORE / 3514225.010901 / 238815728.1Attorney Docket No. A0013430W0016. The flow-reducing implant set forth in any one of claims 4 or 5, wherein the distal end segment of the balloon-expandable longitudinal portion tapers distally toward the pre-defined tapered segment of the shape-memory longitudinal portion.

7. The flow-reducing implant set forth in any one of claims 4-6, wherein a juncture of the distal end segment of the balloon-expandable longitudinal portion and the pre-defined tapered segment of the shape-memory longitudinal portion defines a throat of the flow-reducing implant.

8. The flow-reducing implant set forth in claim 1, wherein the pre-defined tapered segment of the shape-memory longitudinal portion is coupled to the proximal end segment of the balloon-expandable longitudinal portion.

9. The flow-reducing implant set forth in claim 8, wherein the pre-defined tapered segment of the shape-memory longitudinal portion is configured to expand and flare proximally away from the proximal end segment of the balloon-expandable longitudinal portion.

10. The flow-reducing implant of any one of claims 8 or 9, wherein a juncture of the proximal end segment of the balloon-expandable longitudinal portion and the predefined tapered segment of the shape-memory longitudinal portion defines a throat of the flow-reducing implant.

11. The flow-reducing implant set forth in claim 4, wherein the shape-memory longitudinal portion and the balloon-expandable longitudinal portion are configured to form an hourglass shape when the shape-memory longitudinal portion is expanded, and wherein the balloon-expandable longitudinal portion is configured to promote an endothelialization response when in the expanded configuration.

12. A flow-reducing implant for reducing a rate of blood flow through a blood vessel, comprising:a balloon-expandable longitudinal portion having first and second end portions;22CORE / 3514225.010901 / 238815728.1Attorney Docket No. A0013430W001first and second shape-memory longitudinal portions;wherein the first shape-memory longitudinal portion is coupled to the first end portion of the balloon-expandable longitudinal portion and extends outward longitudinally therefrom;wherein the second shape-memory longitudinal portion is coupled to the second end portion of the balloon-expandable longitudinal portion and extends outward longitudinally therefrom; andwherein each of the shape-memory portions are configured to contact the bodily lumen when the flow-reducing implant is in an expanded configuration such that a void is defined therebetween.

13. A flow-reducing implant for reducing a rate of blood flow through a blood vessel, comprising:an implant body configurable between a collapsed configuration and an expanded configuration, wherein the implant body has proximal and distal end portions and a throat portion therebetween when in the expanded configuration; and an embolic device,wherein each of the end portions are configured to contact the blood vessel when the implant body is in the expanded configuration such that a void is defined between the blood vessel and the throat portion,wherein the embolic device is configured to surround the throat portion of the implant body and fill the void to induce thrombosis.

14. The flow-reducing implant set forth in claim 13, wherein the embolic device comprises an embolic coil.

15. A flow-reducing implant for reducing a rate of blood flow through a blood vessel, the flow-reducing implant comprising:23CORE / 3514225.010901 / 238815728.1Attorney Docket No. A0013430W001a balloon-expandable longitudinal portion having a distal end portion and being configured to plastically deform into an expanded configuration due to expansion of a balloon therein; andan over-molded longitudinal portion comprising a polymer material overmolded on the distal end portion of the balloon-expandable longitudinal portion, wherein the over-molded longitudinal portion is configured to resist radial expansion;wherein the balloon-expandable longitudinal portion is configured to induce endothelialization and anchor the flow-reducing implant within the blood vessel when in the expanded configuration;wherein the over-molded longitudinal portion is configured to restrict the flow of blood through the blood vessel such that a backpressure is induced within the blood vessel following an implantation of the flow-reducing implant therein.24CORE / 3514225.010901 / 238815728.1

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