Apparatus and method for changing blood flow characteristics in a blood vessel

Abstract

A device (15, 50, 55, 60, 100, 200) for changing a blood flow characteristic in a blood vessel (20), the device (15, 50, 55, 60, 100, 200) comprising: a cuff (10) configured to be positioned surgically around a portion of the blood vessel (20); a first pad (40) on an inner wall of the cuff (10), wherein the pad (40) causes a cross-sectional area of a passageway (25) extending through the cuff (10) to be locally reduced and / or defines a non-linear passageway (25) within the cuff (10).

Description

Technical Field

[0001] This disclosure relates to an apparatus and method for altering the characteristics of blood flow in a blood vessel. The blood vessel is particularly the carotid artery, but can also be any blood vessel (artery or vein). Specifically, the apparatus and method are designed to prevent or at least reduce the risk of cognitive decline. However, those skilled in the art will understand that the invention can be used in other medical applications. Background Technology

[0002] The heart supplies oxygenated blood to the body through a network of interconnected branching arteries, which originate from the aorta, the largest artery in the body. Figure 1 The diagram shows the heart and selected arteries. The portion of the aorta closest to the heart is divided into three regions: the ascending aorta (where the aorta begins to leave the heart and extends in the superior direction), the aortic arch, and the descending aorta (where the aorta extends in the inferior direction). The three main arteries branching from the aorta along the aortic arch are: the brachiocephalic artery, the left common carotid artery, and the left subclavian artery.

[0003] The brachiocephalic artery extends away from the aortic arch and subsequently divides into the right common carotid artery and the right subclavian artery. The right common carotid artery supplies oxygenated blood to the head and neck, while the right subclavian artery primarily supplies blood to the right arm. The left common carotid artery extends away from the aortic arch and supplies blood to the head and neck. The left subclavian artery extends away from the aortic arch and primarily supplies blood to the left arm. Both the right and left common carotid arteries then branch into separate internal and external carotid arteries.

[0004] The descending aorta extends downwards and defines the descending thoracic aorta, and subsequently defines the abdominal aorta before branching into the left and right iliac arteries. The various organs of the body are supplied with blood by arteries that connect to and are fed by the descending aorta.

[0005] During the systolic phase of the heartbeat, the contraction of the left ventricle forces blood into the ascending aorta, increasing pressure within the arteries (called systolic blood pressure). The volume of blood ejected from the left ventricle creates a pressure wave called the pulse wave, which propagates through the arteries that propel the blood. This pulse wave causes the arteries to expand. When the left ventricle relaxes (the diastolic phase of the heartbeat), the pressure within the arterial system decreases (called diastolic blood pressure), allowing the arteries to contract. This is characterized by a series of positive and negative compression waves and positive and negative expansion waves.

[0006] The difference between systolic and diastolic blood pressure is called pulse pressure, which is typically determined by the strength of the heart's contractions, heart rate, peripheral vascular resistance, and diastolic run-off (e.g., blood flowing down a pressure gradient from arteries to veins), among other factors. High-flow organs, such as the brain, are particularly sensitive to excessive pressure and flow pulsations. Over time, other organs, such as the kidneys, liver, and spleen, can also be damaged by excessive pressure and blood flow pulsations.

[0007] To ensure a relatively consistent flow rate to these sensitive organs, the arterial walls expand and contract in response to pressure waves, absorbing some of the pulse wave energy. However, as the vascular system ages, the arterial walls lose elasticity, leading to increased pulse wave velocity and wave reflection throughout the arterial vascular system.

[0008] Arteriosclerosis weakens the ability of the carotid artery and other large arteries to dilate and inhibit blood flow pulsation, leading to increased systolic and pulse pressure. Consequently, as the arterial walls harden over time, the arteries transmit excessive force to the distal branches of the arterial vascular system.

[0009] Studies have shown that persistently high systolic blood pressure, pulse pressure, and / or pressure variability over time (dP / dt) increase the risk of dementia, such as vascular dementia (e.g., impaired blood supply to the brain, intracranial hemorrhage, or high pulse pressure). Without being bound by theory, high pulse pressure is considered a potential underlying cause or aggravating factor for vascular dementia and age-related dementia (e.g., Alzheimer's disease). Thus, the development of vascular dementia and age-related dementia (e.g., Alzheimer's disease) may also be affected by the loss of elasticity in the arterial walls and the resulting stress on cerebral blood vessels. For example, Alzheimer's disease is often associated with neuroinflammatory plaques and tangles present in the brain. Recent research suggests that increased pulse pressure, increased systolic blood pressure, and / or increased pressure variability over time (dP / dt) may lead to intracranial microbleeds, which may contribute to neuroinflammatory plaques and tangles.

[0010] Increased pulse pressure is a hallmark of vascular aging and has recently been identified as a potential risk factor for cognitive decline and dementia due to its destructive effects on the fragile microvascular system of the brain.

[0011] Studies support the link between high blood pressure in middle age and later cognitive decline or dementia.

[0012] Blood pressure is routinely measured and used as an indicator of various potential conditions. However, blood pressure measurement alone is not an appropriate standard for assessing cognitive decline. This is because a patient's blood pressure may rise or fluctuate due to various factors that may not be related to cognitive decline.

[0013] The actual reason why high pulse pressure leads to brain damage may lie in the "intensity" of the carotid artery wave as it travels forward into the brain. Therefore, the increased amplitude of the pulse-generated wave propagating into the brain may be an important risk factor for subsequent cognitive decline.

[0014] Purpose of the invention

[0015] The object of this invention is to fundamentally overcome or at least improve one or more of the above-mentioned disadvantages, or to provide a useful alternative. Summary of the Invention

[0016] In a first aspect, the present invention provides an apparatus for altering blood flow characteristics in a blood vessel, the apparatus comprising:

[0017] A spiral cuff is configured to surgically position around a portion of the blood vessel; a first abutment is defined by the inner wall of the spiral cuff; and a central ridge is located within the spiral cuff, wherein the abutment:

[0018] This results in a localized reduction in the cross-sectional area of ​​the passage extending through the cuff, and / or

[0019] This alters the cross-sectional shape of the passageway extending through the cuff, and / or

[0020] A non-linear pathway is defined within the cuff.

[0021] The cuff is defined by an elastically deformable spiral body, wherein the spiral body is covered within a compliance layer.

[0022] This article discloses a device for altering blood flow characteristics in blood vessels, the device comprising:

[0023] A cuff is configured to be surgically positioned around a portion of the blood vessel;

[0024] The first adjacent structure is located on the inner wall of the cuff.

[0025] Wherein, the adjacency structure:

[0026] Locally reduce the cross-sectional area of ​​the passage extending through the cuff, and / or

[0027] A non-linear (non-linear) pathway is defined within the cuff.

[0028] The pathway is preferably curved around one or more axes that extend generally perpendicular to the direction of blood flow.

[0029] The first adjacent structure is preferably defined by a first pad.

[0030] The device preferably also includes a second pad and a third pad, wherein the three pads are longitudinally separated within the cuff and spaced apart around the circumferential portion of the cuff.

[0031] The three pads are preferably circumferentially spaced at approximately 120 degrees relative to each adjacent pad.

[0032] The device preferably also includes a second pad that is radially opposite to and axially aligned with the first pad, thereby defining the first pair of pads.

[0033] The device also preferably includes a second pair of pads, which are also radially opposite and axially aligned.

[0034] The first pair of pads is preferably longitudinally spaced relative to the second pair of pads to define an expansion cavity within the cuff.

[0035] The device also preferably includes a third pair of pads, which are also radially opposite and axially aligned.

[0036] The first pair of pads is preferably located near the proximal end of the device, while the second pair of pads is preferably located near the distal end of the device, and the first pair of pads and the second pair of pads are aligned in the circumferential direction.

[0037] The third pair of pads is preferably located between the first pair of pads and the second pair of pads, and wherein the third pair of pads is offset by approximately 90 degrees in the circumferential direction.

[0038] These pads are preferably filled with gel.

[0039] The cuff is preferably defined by a generally tubular body.

[0040] The cuff preferably includes a longitudinally extending seam, which allows the cuff to be positioned around the blood vessel.

[0041] The joint is preferably defined by a first longitudinal extension arm and a second longitudinal extension arm that can be selectively fixed to each other.

[0042] The cuff is preferably defined by a spiral body that can elastically deform, wherein the spiral body is covered within a compliant layer.

[0043] The elastically deformable helical body is preferably made of Nitinol. TM It is made of silicone resin, and the compliance layer is preferably made of silicone resin.

[0044] The radially inner surface of the compliance layer is preferably curved, such that when truncated by a plane parallel to and passing through the longitudinal axis of the helical body, the cross-sectional area of ​​the compliance layer is approximately “D” shaped. However, it should be understood that different shapes and sizes can be provided along the length of this compliance layer portion.

[0045] The radial inner surface of the compliance layer preferably includes at least one inwardly extending protrusion.

[0046] This article discloses a method for altering blood flow characteristics in blood vessels, which includes the following steps:

[0047] Surgically positioning a cuff around a portion of a blood vessel, and

[0048] The blood flow characteristics in a blood vessel are locally altered by means of one or more adjacent structures located within the cuff, these adjacent structures being:

[0049] This reduces the cross-sectional area of ​​the pathway extending through the blood vessel, and / or

[0050] The blood vessel is deformed to define a region that bends around one or more axes that extend generally perpendicular to the direction of blood flow.

[0051] In a second aspect, the present invention provides a method for altering blood flow characteristics in a blood vessel, the method comprising the following steps:

[0052] A spiral cuff is surgically positioned around a portion of a blood vessel, the spiral cuff being defined by an elastically deformable central ridge covered within a compliant layer having at least one abutment structure configured to adjoin the vessel wall; and

[0053] By utilizing one or more adjacent structures located within the cuff, the blood flow characteristics in the blood vessel can be locally altered.

[0054] Reduce the cross-sectional area of ​​the pathway extending through the blood vessel, and / or

[0055] The blood vessel is deformed to define a region that bends around one or more axes that extend generally perpendicular to the direction of blood flow.

[0056] A cable is preferably disposed near the central ridge, extending between the proximal and distal ends of the device. The cable length can be selectively adjusted to change the shape of the helical configuration, such that shortening the cable reduces the pitch of the helical configuration and increases the diameter of the helical configuration.

[0057] The cross-section of the central ridge preferably varies between the proximal and distal ends along the length of the device.

[0058] The cross-section of the spiral cuff preferably varies between the proximal and distal ends along the length of the device.

[0059] The device also preferably includes one or more sensors located on a spiral cuff to obtain data related to blood flow characteristics and / or vascular characteristics within the blood vessel.

[0060] The sensor preferably includes one or more of electrodes, a pressure sensor, and an ultrasonic transmitter.

[0061] One or more sensors are preferably located on the radial interior of the spiral cuff and can be positioned directly adjacent to the blood vessel.

[0062] The sensor is preferably configured to communicate wirelessly with a computer or other such device to transmit information related to the measured blood flow characteristics and / or vascular characteristics.

[0063] The cross-sectional shape of the passage preferably varies between the proximal and distal ends along the length of the device. Attached Figure Description

[0064] Preferred embodiments of the invention will now be described with reference to the accompanying drawings and specific examples, wherein:

[0065] Figure 1 This is a diagram of the human heart;

[0066] Figure 2 This is a schematic diagram of a device for altering blood flow characteristics according to a first embodiment of the present invention;

[0067] Figure 3 yes Figure 2 Another schematic diagram of the device;

[0068] Figure 4 An apparatus for altering blood flow characteristics according to a second embodiment of the present invention is described;

[0069] Figure 5 An apparatus for altering blood flow characteristics according to a third embodiment of the present invention is described;

[0070] Figure 6 An apparatus for altering blood flow characteristics according to a fourth embodiment of the present invention is described;

[0071] Figure 7 This is a side view of the device for altering blood flow characteristics according to the fifth embodiment when deployed;

[0072] Figure 8 yes Figure 7 A three-dimensional view of the device;

[0073] Figure 9 It is based on Figure 7 Another side view of the device used to alter blood flow characteristics;

[0074] Figure 10 yes Figure 7 A cross-sectional side view of a portion of the device;

[0075] Figure 11 yes Figure 7 A cross-sectional side view of a portion of the device when unfolded;

[0076] Figure 12 This is a front view of the device according to the sixth embodiment;

[0077] Figure 13 yes Figure 12 A top view of the device;

[0078] Figure 14 yes Figure 12 and Figure 13 An end view of the device;

[0079] Figure 15 yes Figure 14 Partial details of the end view; and

[0080] Figure 16 yes Figures 12 to 15 A three-dimensional view of the device. Detailed Implementation

[0081] This document discloses several embodiments of devices 15, 50, 55, 60, 100, and 200 for altering blood flow characteristics, which are in the form of an external cuff or strip 10 surgically disposed around the outer wall of a blood vessel 20 (preferably a carotid artery, including the common carotid artery or internal carotid artery). The cuff 10 deforms the arterial wall and thus alters the blood flow characteristics within the channel 9 of the blood vessel 20 by changing the geometry of the blood vessel 20 to change the wall profile of the blood vessel 20 along the length of the cuff 10. Changes in the structure of the container 20 may result in changes in the cross-sectional shape and / or cross-sectional area and / or the curvature of the blood vessel or bending around an axis extending substantially perpendicular to the flow direction (i.e., locally making the blood vessel nonlinear).

[0082] Devices 15, 50, 55, 60, 100, and 200 are preferably disposed around the lateral side of the common carotid artery. Their intended function is to alter the transmission of arterial blood pressure to the cerebral microvascular system and to absorb excess energy from the arterial pulse.

[0083] The devices 15, 50, 55, 60, 100, and 200 of each embodiment all include components arranged around the blood vessel during the surgical procedure.

[0084] In the various embodiments described herein, this device 15, 50, 55, 60, 100, 200:

[0085] This causes the shape of the cross-sectional region of the blood vessel 20 to be locally reduced or altered; and / or

[0086] The vessel 20 extending through the passage 25 is deformed, wherein the passage is non-linear and typically bends or turns (bents) around one or more axes that extend generally perpendicular to the direction of blood flow (i.e., locally makes the vessel non-linear).

[0087] First Embodiment

[0088] exist Figure 2 and Figure 3 In the first embodiment depicted, device 15 includes a cuff 10 that forces a portion of blood vessel 20 into a curved or flexed profile having a curvature about one or more axes extending generally perpendicular to the direction of blood flow (i.e., the blood vessel 20 locally becomes non-linear). As depicted, cuff 10 includes an outer stent 30 made of a suitable biocompatible material such as stainless steel or nitinol. The stent 30 may be formed as two halves and positioned around the blood vessel and attached to each other. Alternatively, the stent may be manufactured as a single component that is sufficiently compliant to allow it to wrap around the blood vessel before subsequently attaching the two opposite sides to define the generally tubular cuff 10.

[0089] Multiple adjacent structures (in the form of pads or cushions 40) are located on the radially inner wall of the cuff 10. The pads 40 are preferably gel pads 40 and may be defined by a single gel pad 40 or multiple independent gel pads 40. Figure 2 and Figure 3 In the embodiment shown, within the wall of the generally locally cylindrical stent 30, the gel pad 40 causes the blood vessel 20 to deform, forcing the blood vessel 20 to adopt a curved profile. Figure 1 The curved portion of the deformed blood vessel 20, schematically depicted in the diagram, has a central concave region and an adjacent convex region, causing the blood flow path to deviate significantly from linearity.

[0090] Pad 40 is not limited to gel pads, but can be made of other materials such as polymers of varying hardness or inflatable pads.

[0091] The gel pad 40 serves two purposes. First, the gel pad 40 defines the desired deformation within the wall of the blood vessel 20. Second, since the outer wall of the blood vessel 20 is in direct contact with the gel pad 40, the gel pad 40 inhibits the energy carried by the blood flow when it comes into contact with the wall of the blood vessel 20.

[0092] Due to the deformation of the blood vessel 20, blood flow is forced to take a non-linear path within the cuff 10. Therefore, the pressure wave traveling axially within the blood vessel 20 is supported against the wall of the blood vessel 20 by the gel pad 40. The gel pad 40 absorbs some of the energy carried by the blood flow.

[0093] Furthermore, the deformation of blood vessel 20 causes the reflected portion of the pressure wave to be non-axial relative to blood vessel 20. This typically results in the reflected wave making contact with the wall of blood vessel 20 at several other locations, which can also reduce the energy intensity carried by the pressure wave downstream of cuff 10.

[0094] exist Figure 2 and Figure 3 In the first embodiment, the gel pad 40 and cuff 10 are arranged to introduce curvature into the blood vessel 20, but maintain a generally circular cross-sectional area within the blood vessel 20, such that the blood vessel 20 maintains approximately its native diameter. In an alternative embodiment, in addition to introducing curvature into the blood vessel 20, the cuff 10 may also alter the cross-sectional area (cross-sectional area) or shape of the blood vessel 20. For example, the blood vessel may be locally flattened along its length to an oval or elliptical cross-section, having a cross-sectional area smaller than the natural cross-sectional area of ​​the blood vessel 20. The modified cross-section of the blood vessel 20 can be of any shape, but typically the entire cross-section is flattened and widened.

[0095] Since the strip-shaped cross-sectional profile (once flattened) is more easily deformed, this partial flattening of the blood vessel 20 can hopefully increase the vessel's ability to bend.

[0096] The diameter (and length) of the passage 25 through the tubular stent 30, relative to the natural outer diameter of the blood vessel 20, defines the amount of tortuosity of the blood vessel (which can be achieved by a given cuff 10).

[0097] Second Embodiment

[0098] Figure 4 The device 50 of the second embodiment is depicted. In this embodiment, three gel pads 40 are arranged circumferentially around the cuff 10. The gel pads 40 are spaced approximately uniformly in the longitudinal direction. The gel pads 40 are offset approximately 120 degrees circumferentially relative to each adjacent gel pad 40. The radial spacing of the gel pads 40 forces blood flow to follow a more circuitous (non-linear) path. Moreover, this arrangement facilitates several contact points at which axial pressure waves carried by the blood flow are forced to contact the wall of the blood vessel 20 at a position supported by a gel pad 40.

[0099] Because of the presence of three gel pads 40, when viewed axially through the vessel 20, there is a restricted cross-sectional area within the vessel 20 that is unaffected by any one of the gel pads 40. In some arrangements, due to the degree of deformation provided by the gel pads 40, there may be no straight site passing through the vessel 20. However, because the gel pads 40 are axially spaced, each gel pad 40 only partially restricts or alters the shape of a local cross-sectional area of ​​the vessel 20. Therefore, since the local cross-sectional area of ​​the vessel 20 does not change significantly relative to its natural cross-sectional area at any location, the volumetric blood flow through the device 50 is not significantly affected. Thus, the device 50 can deflect and / or absorb some of the energy carried by the pressure wave without significantly impeding the volumetric blood flow rate.

[0100] As in Figure 4 As shown, the stent is defined by a tube surrounding the blood vessel and has longitudinal slits defining two arms 35. The arms 35 can be secured to each other by welding, suturing, gluing, stapling, corresponding male and female engagement formations, or some other means that allow the arms 35 to be quickly attached to each other during surgery. It should be understood that in embodiments where the stent is made of a metallic material such as nitinol, this engagement may not be necessary.

[0101] Third Embodiment

[0102] exist Figure 5 The third embodiment of the device 55 is depicted. The third embodiment is functionally similar to the second embodiment described above. However, it has three pairs of gel pads 40. The first pair of gel pads 42 are arranged radially opposite each other at the first (proximal) end 52 of the device 55. The second pair of gel pads 46 are arranged radially opposite each other approximately at the second (distal) end 56 of the device 55.

[0103] The third pair of gel pads 44 is disposed in the longitudinal central region 54 of the device 55 and adjacent to the first pair of gel pads. The third pair of gel pads 44 is offset axially by approximately 90 degrees relative to the first pair of gel pads 42 and the second pair of gel pads 46.

[0104] Each pair of gel pads 42, 44, 46 locally flattens the vessel 20, causing the vessel 20 to locally adopt an oval or elliptical outline, or at least a non-circular outline. In this way, at the junction between each pair of gel pads 42, 44, 46, the pressure wave contacts the stepped change portion in the geometry of the vessel 20.

[0105] Similar to the second embodiment described above, when viewed axially through the blood vessel 20, there is a restricted cross-sectional area within the blood vessel 20 that is unaffected by any of the gel pads 40 and is located at the radial center of the blood vessel 20.

[0106] Fourth embodiment

[0107] exist Figure 6 The fourth embodiment of the device 60 is depicted. This fourth embodiment is similar to the third embodiment described above, but the middle pair of gel pads is omitted. Thus, in the fourth embodiment, there is a first pair of gel pads 62 and a second pair of gel pads 66, the first pair of gel pads being located at a first end 64 of the device 60, and the second pair of gel pads 66 being located at the opposite second end 68 of the device 60.

[0108] In the fourth embodiment, the space between the grouped gel pads 62, 66 defines an expansion cavity 70 located in the longitudinal central region of the device 60. The expansion cavity 70 allows the blood vessel 20 to locally expand or bulge, thereby causing a remodeling of the vessel's geometry and potentially reducing pressure within the vessel 20. The expansion of the portion of the blood vessel 20 located within the expansion cavity 70 can occur permanently within the device 60, or thereby alter the blood pressure within the vessel.

[0109] In a variant of the fourth embodiment not shown in the figure, the gel pads 62 and 66 may be offset at an angle of approximately 90 degrees relative to each other in the circumferential direction, and the expansion cavity 70 is located therebetween.

[0110] Although the pads described in the various embodiments have been depicted as separately formed components, it should be understood that these pads may be integrally formed with the cuff 10.

[0111] Fifth embodiment

[0112] exist Figures 7 to 11 The fifth embodiment of the device 100 is depicted. The device 100 has a generally spiral body or cuff 110 and, in a manner similar to the embodiments described above, is intended to be disposed externally around the lateral side of the common carotid artery or internal carotid artery.

[0113] The device 100 has a spiral profile, which allows it to be positioned around the blood vessel 20 with minimal disturbance during the procedure. The elasticity of the device 100 allows the blood vessel 20 to be radially positioned in the central passage 25, which extends longitudinally through the spiral configuration of the device 100.

[0114] Device 100 includes materials such as medical-grade Nitinol TMThe central ridge 120 may be made of another suitable metal, metal alloy, or polymer resilient deformable material. The ridge 120 is sheathed within a silicone cover 130 or another suitable polymer cover. The silicone 130 is compliant and reduces the risk of any damage to the outer wall of the blood vessel 20. Although the device is depicted with a silicone cover 130, it may alternatively be manufactured without a cover 130, such that the ridge 120 defines the outer surface for adjoining the blood vessel 20.

[0115] Device 100 is a single-piece device without hinge components, which is constructed in an open spiral configuration with a preferred total length of about 45 mm, but can also be set to other lengths, in the range of 20-55 mm for the common carotid artery, but longer or shorter for other vessels 20.

[0116] As in Figure 7 As depicted, device 100 is designed to fit around the lateral side of the common carotid artery or internal carotid artery and bias the artery along its length (smoothly and continuously). For example, an 8 mm diameter common carotid artery will be biased approximately 6 degrees from its long axis multiple times as it passes through device 100. Artery 20 returns to its natural path upon exiting device 100. The inner spiral diameter of the defining central passage 25 of device 100 is chosen to be smaller than the local arterial outer diameter in order to properly bias the artery. However, because device 100 deforms the artery only at the point of contact, i.e., along the spiral configuration, it does not substantially change the cross-sectional area or shape of the artery, as the device does not completely encircle the artery at any point. If the pitch is small enough, device 100 can reduce the diameter of the artery. In this case, it can bias and reduce the cross-sectional area of ​​the artery. The pitch of device 100 can be constant or variable. If the helix pitch is small enough, the device 100 can behave like a continuous tube with very small gaps or no gaps between adjacent peaks of the helical configuration.

[0117] like Figure 10 The central spiral ridge 120, as depicted in the text, is made by Nitinol TM The winding plate portion is made such that the ridge 120 is wound around a longitudinal helical axis. Thus, the ridge 120 is elastically deformable and capable of unwound to wind the blood vessel 20 before springing back to the natural diameter of the device 100. The helical ridge 120 is preferably pre-formed as a self-supporting helical configuration and is manufactured, for example, in a heat-setting process.

[0118] refer to Figure 10The cross-sectional shape of the silicone coating 130 is typically contoured such that its outline is oblong, elliptical, oval, or other such configurations. This creates a gradual deformation of the blood vessel 20 and reduces the risk of damage to the blood vessel 20. It also helps to create a gradual transition within the blood vessel 20 from an area with its natural diameter to an area deformed by the device 100.

[0119] exist Figure 11 In one embodiment illustrated, the radially outer surface of the silicone resin 130 may be defined by a portion of a cylinder or tube, such that the radially outer surface is partially parallel to the longitudinal axis of the device 100. Conversely, the radially inner surface of the silicone resin 130 is curved, and when cut by a plane parallel to and passing through the longitudinal axis of the helical configuration, the cross-sectional area of ​​the silicone resin 130 is approximately “D” shaped.

[0120] Device 100 is designed to locally alter a blood vessel by changing its shape and / or diameter and / or flow direction. For example, device 100 can reduce the natural cross-sectional area of ​​the blood vessel by about 5% to 30%, preferably between about 10% and 20%, and most preferably about 15%. However, the reduction in cross-sectional area may be higher, reaching 50%. To accommodate blood vessels with different cross-sectional areas, device 100 is manufactured in different helical diameters, and the device 100 with the most suitable size is selected before surgery to achieve optimal fit with the patient's vascular geometry and the expected limitations of the cross-sectional area. It is envisioned that device 100 can be provided in about 12 different sizes, and the preferred size can be determined by imaging before surgery. Another method to reduce the passage 25 in device 100 is to change the silicone covering 130 to a thicker or thinner version on the inside of the device. Furthermore, the device can be shortened and the inner diameter increased by placing a cable at one end and pulling it from the other end. For this purpose, the nitinol ridge can be a hollow tube. As described below in the sixth embodiment, the cable can be shortened or lengthened by rotating a screw at one end of the device.

[0121] exist Figures 7 to 9 In the embodiments depicted, the length of device 100 is a multiple of approximately 1.5 times the pitch. It should be understood that the length of device 100 can be some other multiple of the pitch, for example, between approximately 1 and 2 times the pitch. In more extreme cases, the coil can be up to 30 times the pitch or greater. Alternatively, device 100 can be configured to a fixed length, independent of the pitch.

[0122] refer to Figure 9Multiple inwardly extending protrusions 140 may be formed on the inner wall of the silicone resin covering 130. These protrusions 140 help to further deform the blood vessel 20 locally. These protrusions 140 may be intermittently spaced along the length of the helical configuration and all point radially inward.

[0123] It should be understood that Nitinol TM The ratio of the cross-sectional area of ​​ridge 120 to silicone 130 can vary beyond the embodiments depicted in the figures. For example, by providing Nitinol in a thicker cross-sectional area... TM This can increase the hardness of the device by 100. It should be understood that the cross-section of nitinol can vary along its length, so for example, the ends are hard and the middle is soft.

[0124] The fifth embodiment of the spiral configuration device 100 is similar to that described above. Figure 4 The embodiments are operated in a manner similar to those of the fifth embodiment. As shown in the accompanying drawings, a pad 40 is provided in a construction that is functionally similar to the helical configuration of the fifth embodiment. Similarly, the silicone resin (of the fifth embodiment) located on the inner surface of the helical configuration provides cushioning to the outer wall of the blood vessel in a manner similar to that of the pad 40 in the first to fourth embodiments.

[0125] Sixth Embodiment

[0126] exist Figures 12 to 16 The sixth embodiment of the device 200 is depicted, which is a variation of the fifth embodiment of the device 100. The device 200 has a generally spiral-shaped body or cuff 210 and is disposed externally around the outside of the common carotid artery or internal carotid artery (or other suitable blood vessel) in a manner similar to the embodiments described above.

[0127] The radial inner wall of the cuff 210 can be smooth or textured.

[0128] The device 200 has a spiral profile, which allows it to be positioned around the blood vessel 20 with minimal disturbance during the procedure. The flexibility of the device 200 allows the blood vessel 20 to be radially positioned within the central passage 25 that extends longitudinally through the spiral configuration.

[0129] The device 200 includes components such as medical-grade Nitinol. TM A central ridge 220 is made of stainless steel, or other suitable metal, metal alloy, or polymer elastic deformable material. This ridge 220 is sheathed within a silicone resin 230 or another biocompatible polymer cover. The silicone resin cover 230 is compliant and reduces the risk of any damage to the outer wall of the blood vessel 20.

[0130] refer to Figure 12 The tension line or cable 240 extends, for example, through the helical configuration, adjacent to the central ridge 220. In this preferred embodiment, the tension line 240 is secured to the central ridge 220 by means of a plurality of spaced anchor points 250. The anchor points 250 can be configured in various different forms, such as lugs 250 with eyelets, for receiving the line 240. Similarly, the tension line 240 can pass through the center of the hollow ridge 220.

[0131] refer to Figure 14 and Figure 15 The cable 240 has an adjustment mechanism 260 located at one end of the device 200. This adjustment mechanism 260 can be in the form of interacting threads and nuts, a worm gear drive, a slotted screw of the hose clamp type, or some other mechanism configured to selectively mechanically shorten the length of the cable 240. By shortening the cable 240, since the ends of the cable are attached to the central ridge 220 and intermittently attached to the anchor point 250, shortening the cable 240 results in a reduction in the length and an increase in the diameter of the helical configuration. This has the effect of radially expanding the device 200 surrounding the blood vessel.

[0132] The radial expansion or contraction of the helical configuration can be performed manually during installation, or alternatively, it can be performed remotely or mechanically during a postoperative procedure, as will be discussed below. For example, cable 240 can be adjusted intermittently or occasionally, such as remotely or mechanically during a keyhole surgical procedure (a minimally invasive surgical procedure). Such adjustments can be performed to accommodate changes in the blood vessels, changes in the patient's blood flow characteristics, or for any other purpose.

[0133] refer to Figure 12 The device 200 includes a radio component 280 and a copper coil winding 290, or other such antenna.

[0134] The radio component can receive signals, such as guiding the expansion or contraction of the spiral configuration in diameter.

[0135] refer to Figure 13 The device 200 also includes a tag 300 containing a sensor that is positioned relative to other associated components on the helical configuration to enable measurements of radially opposing sides of the helical configuration. One such component may be a mirror or reflector 320 for ultrasonic purposes, or an LED receiver 330.

[0136] Various sensors or communication devices can be mounted on the spine 220 or the silicone resin covering 230, such as platinum electrodes 340, pressure sensors 360, and ultrasonic transmitters 380.

[0137] In this preferred embodiment, the electrode 340 and the pressure sensor 360 extend radially inward through the surface of the silicone cover 230, so that the electrode 340 and the pressure sensor 360 can be configured to make direct contact with the wall of the blood vessel 20.

[0138] refer to Figure 15 The central ridge 220 can be made from a sandwiched nickel-titanium spiral configuration 400.

[0139] The sensors and adjustment mechanisms of device 200 can be controlled via a printed circuit board (PCB), such as... Figure 15 The doubled-up flex PCB 410 is depicted in the image.

[0140] In the various embodiments described herein, the length of the cuff 10 is typically about 40mm–50mm, although it may be longer or shorter.

[0141] When processed by the devices of the first to fourth embodiments described above, the diameter of the blood vessel 20 can be reduced by about 3% to 30%, preferably about 5% to 15%, and most preferably about 10% by each pad.

[0142] exist Figures 2 to 6 In one embodiment, the inner diameters of devices 15, 50, 55, and 60 are changed by altering the dimensions of the silicone resin covering 130. Figures 7 to 16 In some embodiments, the inner diameter of the helical configuration can be changed by altering the size (particularly the thickness) of the silicone cover 120 or the size of the ridge 130.

[0143] Alternatively, the inner diameter can be changed by a mechanism such as shortening the cable, for example, as described with respect to the sixth embodiment.

[0144] It should be understood that the cross-section of the silicone cover 130 may be constant between the proximal and distal ends. Alternatively, the cross-section of the silicone cover 130 may vary between the proximal and distal ends. Similarly, the cross-section of the central ridge 220, preferably made of nitinol, may vary.

[0145] Advantageously, when positioned around a blood vessel 20 (such as the carotid artery), the cuff 10 does not significantly affect the blood flow rate because the autoregulation of blood flow helps maintain the blood flow rate of the natural volume.

[0146] Although the invention has been described with reference to specific examples, those skilled in the art will understand that the invention can be implemented in many other forms.

Claims

1. A device for altering blood flow characteristics in a blood vessel, the device comprising: A spiral-shaped cuff is configured to be surgically positioned around a portion of the blood vessel; The first adjacent structure is defined by the inner wall of the spiral cuff; and a central ridge, located within the spiral cuff, wherein the adjacent construction: This results in a localized reduction in the cross-sectional area of ​​the passage extending through the cuff, and / or This alters the cross-sectional shape of the passageway extending through the cuff, and / or A non-linear pathway is defined within the cuff. The cuff is defined by a spiral body that is elastically deformable and open at both ends, wherein the spiral body is covered within a compliant layer.

2. The apparatus according to claim 1, wherein, The elastically deformable helical body is made of Nitinol™, and the compliance layer is made of silicone.

3. The apparatus according to claim 1 or 2, wherein, The radial inner surface of the compliance layer is curved, such that when cut by a plane parallel to and passing through the longitudinal axis of the helical body, the cross-sectional area of ​​the compliance layer is approximately "D" shaped.

4. The apparatus according to claim 1 or 2, wherein, The radial inner surface of the compliance layer includes at least one inwardly extending protrusion.

5. The apparatus according to claim 1 or 2, wherein, A cable is positioned adjacent to the central ridge, extending between the proximal and distal ends of the device. The length of the cable can be selectively adjusted to change the shape of the helical configuration, thereby shortening the cable reduces the pitch of the helical configuration and increases the diameter of the helical configuration.

6. The apparatus according to claim 1, wherein, The cross-sectional area of ​​the passage varies between the proximal and distal ends along the length of the device.

7. The apparatus according to claim 1, wherein, The cross-sectional shape of the passage varies between the proximal and distal ends along the length of the device.

8. The apparatus according to claim 1, wherein, The cross-section of the spiral cuff varies between the proximal and distal ends along the length of the device.

9. The apparatus according to any one of claims 1, 2, 6-8, further comprising one or more sensors located on the spiral cuff to obtain data relating to blood flow characteristics and / or vascular characteristics within the blood vessel.

10. The apparatus according to claim 9, wherein, The sensor includes one or more of electrodes, a pressure sensor, and an ultrasonic transmitter.

11. The apparatus according to claim 9, wherein, The one or more sensors are located radially inside the spiral cuff and can be positioned directly adjacent to the blood vessel.

12. The apparatus according to claim 9, wherein, The sensor is configured to communicate wirelessly with a computer or other such device to transmit information related to the measured blood flow characteristics and / or vascular characteristics.

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