Composite vascular shunt

Abstract

A composite vascular shunt includes a tubular mesh frame including a mesh covering and an opening. The tubular mesh frame is collapsible and can be configured to expand from a collapsed shape to a tubular shape when the vascular shunt is deployed. The mesh covering conforms to the shape of the tubular mesh, is surrounded by the tubular mesh frame, and is less porous than the tubular mesh frame. The opening is located within the mesh covering. A delivery wire passes through the opening in order to guide the shunt into position over an aneurysm.

Description

TECHNICAL FIELD

[0001] The present disclosure relates generally to intravascular medical devices. The present disclosure more particularly relates to medical devices for treating vascular trauma and deformities. BACKGROUND

[0002] Current vascular shunts consist of a low-porosity braid deployed across the neck of an aneurysm and not only cover the perimeter of the blood vessel across the neck of the aneurysm but also cover a length of otherwise healthy blood vessel located proximal and distal to the neck of the aneurysm. Thromboembolic complications are often caused by these types of devices. Patients using such devices are long-term medicated to mitigate the risk of device thrombosis.

[0003] An ideal endoluminal shunt would treat only the neck of the aneurysm, thereby minimizing the amount of metal in the lumen of the blood vessel and the likelihood of thromboembolic complications. However, with currently available imaging technology, it is difficult to position a neck-of-aneurysm covering against the neck of the aneurysm under fluoroscopy guidance in three-dimensional space.

[0004] Intravascular devices that minimize the amount of metal in the blood vessel by targeting only the neck of the aneurysm are not commercially available. Commercially available devices that attempt to treat the neck of the aneurysm within the blood vessel, such as various aneurysm embolization systems (e.g., embolic coils). SUMMARY

[0005] The present disclosure describes various examples of intravascular shunt devices designed to minimize the amount of metal in the blood vessel by targeting only the neck of the aneurysm, devices for deploying intravascular shunt devices, and methods for guiding and deploying shunt devices to cover the neck of the aneurysm.

[0006] In one example of the present disclosure, a vascular shunt includes a tubular mesh frame including a mesh covering and an opening. The tubular mesh frame is collapsible and configured to expand from a collapsed shape to a tubular shape when the vascular shunt is deployed. The mesh covering is conformal to the shape of the tubular mesh, surrounded by the tubular mesh frame, and less porous than the tubular mesh frame. The opening is located within the mesh covering.

[0007] In one example, the tubular mesh frame has a circular cross-section. In one example, the mesh covering has a rounded perimeter. In another example, the mesh covering has a circular perimeter. In some examples, the mesh covering is integral with the tubular mesh frame. In other examples, the mesh covering is separate from the tubular mesh frame and attached to the tubular mesh frame. In one example, the mesh covering is attached to the tubular mesh frame by welding. In another example, the mesh covering is attached to the tubular mesh frame by interweaving mesh strands of the mesh covering with mesh strands of the tubular mesh frame.

[0008] In one example of the disclosure, a device for deploying a vascular shunt includes a hollow microcatheter including a tubular outer wall, a distal end, and a proximal end. In one example, the distal end of the microcatheter includes a transverse opening substantially perpendicular to a longitudinal axis of the microcatheter and further includes a longitudinal opening substantially parallel to the longitudinal axis. The longitudinal opening intersects the transverse opening. The device further includes a delivery wire including a distal segment, a proximal segment, and a joint between the distal segment and the proximal segment. At least a portion of the distal segment of the delivery wire is configured to adopt a curved configuration. The distal segment has a smaller cross-section than the proximal segment.

[0009] In one example, the portion of the distal segment of the delivery wire configured to adopt a curved configuration is pre-shaped into a curved configuration and is configured to recover from a straightened configuration to the curved configuration upon deployment of the distal segment of the delivery wire from the microcatheter.

[0010] In another example, the delivery wire includes a pull wire. The pull wire is positioned in a lumen of the delivery wire and terminates at a distal end of the distal segment. A proximal end of the pull wire is pullable to apply a tension force to the pull wire that pulls at least a portion of the distal segment of the delivery wire to a curved configuration.

[0011] In one example, a radiopaque marker can be secured to the joint between the distal segment and the proximal segment of the delivery wire. In another example, a radiopaque marker can be secured to a distal end of the distal segment of the delivery wire. In another example, a distal end of the distal segment of the delivery wire can be a coil formed of a radiopaque material. In another example, a radiopaque marker can be secured to the distal end of the microcatheter. In one example, the radiopaque marker secured to the distal end of the microcatheter can be between the proximal ends of the transverse opening and the longitudinal opening. In another example, the radiopaque marker secured to the distal end of the microcatheter includes an open ring shape. In another example, the opening of the open ring shape spans the longitudinal opening of the microcatheter.

[0012] In one example of the disclosure, a method for deploying a vascular shunt includes advancing a microcatheter in a distal direction across a neck of an aneurysm in a blood vessel, advancing a distal tip of a delivery wire out of the microcatheter, rotating the microcatheter so that a curved delivery wire tip exits through a longitudinal slot in the microcatheter, thereby radially aligning a mesh cover with an aneurysm entrance, and guiding the distal tip of the delivery wire into the aneurysm. The method further includes withdrawing the microcatheter in a proximal direction while maintaining the position of the delivery wire so that a self-expanding frame of the vascular shunt opens against an inner wall of the blood vessel and the distal tip of the delivery wire guides the mesh cover of the vascular shunt across the neck of the aneurysm.

[0013] In another example, the method further includes confirming, via the radiological imaging device, that the distal tip of the delivery wire is located within the aneurysm. In another example, the method includes withdrawing the delivery wire into the microcatheter and withdrawing the delivery wire and microcatheter from the patient. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 is a drawing of a shunt according to the present disclosure, showing the main components of the shunt and their relationship to each other.

[0015] Figure 2 is a drawing of a microcatheter for delivering a shunt according to the present disclosure, showing the main components of the microcatheter and their relationship to each other.

[0016] Figure 3 is a drawing of one example of a delivery wire for delivering a shunt according to the present disclosure, showing the main components of the delivery wire and their relationship to each other.

[0017] Figure 4 is a cross-sectional view of one example of a microcatheter with a delivery wire and shunt according to the present disclosure, the delivery wire and shunt being mounted in preparation for placement in a blood vessel.

[0018] Figures 5a-5f is a series of drawings of an aneurysm in a blood vessel according to the present disclosure, showing an example of a sequence of steps for placing a shunt in a blood vessel to occlude the aneurysm.

[0019] Figure 6 is a flowchart showing an example of a sequence of steps for placing a shunt in a blood vessel to occlude the aneurysm.

[0020] Figure 7 is a drawing of a shunt according to the present disclosure in a collapsed configuration.

[0021] Figure 8 is a drawing of a cross-section of a collapsed shunt according to the present disclosure. Figure 7

[0022] Figure 9 is a drawing of another cross-section of a collapsed shunt according to the present disclosure. Figure 7 DETAILED DESCRIPTION

[0023] Various examples of computing devices and methods will now be disclosed in detail with reference to the drawings, wherein like reference numerals indicate like parts, throughout the several views.

[0024] Figure 1 ​​is a diagram of a flow diverter 100. The flow diverter 100 includes a self-expanding tubular mesh frame 102 with high porosity. "High porosity" indicates that the mesh of the component includes more open space than the vessel it covers. A high porosity component thus has a low metal-to-artery ratio. The metal-to-artery ratio is calculated by dividing the cylindrical area covered by the device in the artery by the total cylindrical area of the artery segment containing the device. The tubular mesh frame 102 has an expanded (free) state and a collapsed state. The expanded state is shown. The tubular mesh frame 102 must be compressed externally to enter the collapsed state and return to the expanded state under suitable conditions. In some examples, the tubular mesh frame 102 can automatically return to the expanded state under the action of internal tension as soon as the external constraint is removed. In other examples, the tubular mesh frame 102 can return to the expanded state in response to a thermal input or an electrical signal. One example of such a tubular mesh frame 102 can be made of a shape memory alloy such as nickel-titanium alloy (nitinol).

[0025] A low porosity (high metal-to-artery ratio) mesh covering 104 is combined with the tubular mesh frame 102. The mesh covering 104 is placed over the middle segment of the tubular mesh frame 102. The mesh covering 104 can generally have a circular, rounded, or oblong shape 110. An opening 106 is formed in the center of the mesh covering 104. The opening 106 is large enough to allow a guide device such as a steerable radiopaque guide wire (or microcatheter) to pass through it.

[0026] In some examples, the mesh covering 104 can be integrated as part of the tubular mesh frame 102. In one example, the mesh covering 104 can be woven from the same filaments as the tubular mesh frame 102 but in a tighter manner. In other examples, the mesh covering 104 can be a separate element that is attached to the tubular mesh frame 102. In one such example, the mesh covering 104 can be attached to the tubular mesh frame 102 by welding. In another such example, the mesh covering 104 can be attached to the tubular mesh frame 102 by adhesive. In another example, the filaments of the mesh covering 104 can be interwoven with the filaments of the tubular mesh frame 102. In another such example, the mesh covering 104 can be attached to the tubular mesh frame 102 by temporarily or locally melting either the mesh covering 104 or the tubular mesh frame to fuse them together (as opposed to welding, which temporarily melts both to form a bond). In another such example, the mesh covering 104 can be attached to the tubular mesh frame 102 by sandwiching the mesh covering 104 between layers of the tubular mesh frame 104, or vice versa.

[0027] Figure 7The shunt 100 in a collapsed state is shown. The collapsed portion 700 is formed in the tubular mesh frame 102 and the mesh cover 104 to accommodate the distal end 302 of the delivery line 300 when the shunt is advanced through the microcatheter 200 for placement over the aneurysm (further details regarding the tools and techniques used for delivery and placement of the shunt 100 are provided below). Figure 8 A cross-section of the collapsed diverter 100, extending only through the tubular mesh frame 102, is shown. The collapsed portion 100 can be seen more clearly in this cross-sectional view. Figure 9 A cross-section of the collapse diverter 100 passing through the center of the opening 106 is shown. Thus, the collapse portion 700, the opening 106, the tubular mesh frame 102, and the mesh cover 104 can be seen.

[0028] Figure 2 A microcatheter 200 for delivering a shunt 100 is shown. The microcatheter 200 has a tubular outer wall 202, a distal end 204, a proximal end 206, and a longitudinal axis 210 that approximately coincides with the center of the tubular outer wall 202 along its length. The distal end includes a lateral opening 208 and a longitudinal opening 212. In some examples, the lateral opening 208 may be substantially perpendicular to the longitudinal axis 210. In some examples, the lateral opening 208 may be angled to the longitudinal axis 210.

[0029] The longitudinal opening 212 may be a slot or a similar shape having a long dimension along the length of the microcatheter 200 and a short dimension along the circumference (or other non-circular periphery) of the microcatheter 200. One end of the longitudinal opening 212 intersects 214 with a transverse opening 208 located at the distal end 204 of the microcatheter 200. The other end of the longitudinal opening may be square (i.e., including right-angled corners with or without radius), semi-circular, or elliptical.

[0030] The distal end 24 of the microcatheter 200 may also include a radiopaque marker 218. The radiopaque marker 218 allows clinicians to visualize the location of the distal end 204 of the microcatheter 200 within the patient's vascular system using radiographic instruments. For example, clinicians may use fluoroscopy, digital subtraction angiography, rotational angiography, computed tomography (CT), cone-beam CT, etc., to visualize the location of the radiopaque marker 218. In some examples, the radiopaque marker 218 may be a circular band or annular shape. In some other examples, the circular band may be an open ring shape, wherein the opening in the ring is aligned with the longitudinal opening 212.

[0031] Figure 3A manipulable delivery line 300 for delivering a shunt 100 is shown. The delivery line 300 is deployed within a microcatheter 200. The delivery line 300 includes a distal segment 302, a proximal segment 304, and a connector 306 located between the distal segment 302 and the proximal segment 304. At least a portion of the distal segment 302 of the delivery line 300 is configured to adopt a curved configuration. The distal segment 302 has a smaller cross-section than the proximal segment 304. In some examples, the distal segment 302 is slidable relative to the proximal segment 304. This allows the tip of the delivery line to retract after the shunt has been placed across the neck of the aneurysm. In some examples, both the distal segment 302 and the proximal segment 304 have circular cross-sections. In other examples, the distal segment 302 and the proximal segment 304 may have non-circular cross-sections. For example, either the distal segment 302 or the proximal segment 304 may have an elliptical, rectangular, oval, triangular, or quadrilateral cross-section. Furthermore, in some examples, the non-circular cross-section of either the distal segment 302 or the proximal segment 304 may not have a consistent angular orientation along the length of the delivery line 300. The distal segment 302 includes a terminal 310. In some examples, the terminal 310 may include a radiopaque marker 314.

[0032] In one example, a portion of the distal segment 302 of the delivery line 300 is configured to adopt a curved configuration, pre-set in a curved configuration, and reverts from a straight configuration to a curved configuration upon deployment from the microcatheter. Thus, when the delivery line is in its free state, the segment is in a curved configuration. When the delivery line is inserted into the microcatheter, the inner diameter of the microcatheter constrains the delivery line and forces the curved configuration to straighten. When the delivery line is deployed from the microcatheter, the segment reverts to its pre-set curved configuration. The curved segment may be formed from a flexible, elastic material. For example, the curved segment may be formed from spring steel, or may be heat-treated to form a curved segment in its free state.

[0033] In another example, at least one traction suture 308 is positioned within the lumen 316 of the delivery line 300. One or more traction sutures 308 are attached to the end 310 of the distal segment 302 such that when the traction suture 308 is pulled from the proximal end 318 of the proximal segment 304 of the delivery line 300, it causes at least a portion of the distal segment 302 near the end 310 to bend. This allows clinicians to guide the end 310 of the distal segment 302 of the delivery line 300 into the aneurysm. In some examples, the entire distal segment 302 may bend when the traction suture 308 is pulled. In other examples, a portion of the proximal segment 304 may also bend when the traction suture 308 is pulled.

[0034] The connector 306, located between the distal segment 302 and the proximal segment 304, has a cross-section at least as large as that of the proximal segment 304. The connector 306 is used to push the shunt 100 away from the microcatheter 200 for placement across the aneurysm neck, as will be explained in more detail below. In some examples, the connector 306 may also include a radiopaque marker 312.

[0035] Figure 4 This is a cross-sectional view of a microcatheter 200 having a delivery line 300 and a shunt 100, which are installed in preparation for placement in a blood vessel. The shunt 100 is mounted above the distal segment 302 of the guidewire 300 by guiding the opening 106 over the distal segment 302 until the tubular mesh frame 102 converges with the connector 306 located between the distal segment 302 and the proximal segment 304 of the delivery line 300. The tubular mesh frame 102 of the shunt 100 is then compressed to its collapsed state, preloaded into a guide (not shown), and delivered into the lumen 220 of the microcatheter.

[0036] Figures 5a-5f These are a series of figures illustrating an example of a sequence of steps for placing a shunt 100 into a blood vessel 514 to close an aneurysm 512. Figure 5a At this point, the microcatheter 200 was advanced across the neck 516 of the aneurysm 512. Figure 5b If necessary, check and adjust the longitudinal opening 212 of the microcatheter 200 to be radially aligned with the aneurysm. The distal segment 302 of the delivery suture 300, with its end 310, is then advanced out of the microcatheter 200 and guided through the neck 516 of the aneurysm 512. The delivery suture may have a preset curvature, as described above, or may be guided using a traction suture 308. The delivery suture engages with but is not attached to the implant through the through-hole 106. Figure 5c After confirming that the distal segment 302, distal segment 310, is seated within the aneurysm 512, the shunt 100 can be deployed. The shunt 100 is deployed by retracting the microcatheter 200 while maintaining the position of the delivery line 300.

[0037] exist Figure 5d At this point, the extended tubular frame 102 opens against the interior of the blood vessel 514, and the shunt 100 is guided through its opening 106 along the distal segment 302 of the delivery line 300. Figure 5e At this point, the shunt 100 is fully deployed and extended from the microcatheter 200. Figure 5f At this point, the delivery line 300 is withdrawn into the microcatheter 200, and both the delivery line and the microcatheter can be withdrawn from the patient.

[0038] Figure 6This is a flowchart illustrating the sequence of steps for placing a shunt in a blood vessel to close an aneurysm. At 600, the clinician advances a microcatheter distally across the neck of the aneurysm in the vessel. At 602, the clinician advances the distal end of the delivery line away from the microcatheter and guides the distal end of the delivery line into the aneurysm. At 604, the clinician confirms via a radiographic imaging device that the distal end of the delivery line is located within the aneurysm. The radiographic imaging device may include, for example, fluoroscopy, digital subtraction angiography, rotational angiography, computed tomography (CT), cone-beam CT, etc. At 606, the clinician deploys the shunt from the microcatheter. At 608, while maintaining the position of the delivery line, the clinician withdraws the microcatheter proximally, causing the self-expanding frame of the shunt to open against the inner wall of the vessel, while the distal end of the delivery line guides the mesh cover of the shunt across the neck of the aneurysm. At 610, the clinician withdraws the delivery line into the microcatheter. At position 612, the clinician removes the delivery line and microcatheter from the patient.

[0039] To facilitate understanding of the principles and structural features of the disclosed technology, illustrative examples have been explained above. Components described as constituting various elements of the disclosed technology are intended to be illustrative rather than limiting. Many suitable components that will perform the same or similar functions as those described herein are intended to be covered within the scope of the disclosed electronic devices and methods. Such other components not described herein may include, but are not limited to, components developed, for example, after the development of the disclosed technology.

[0040] It should also be noted that, unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “the” used in this specification and the appended claims include plural references.

[0041] "Including" or "containing" means that at least the named component, element, or method step is present in the article or method, but does not exclude the presence of other components, materials, elements, or method steps, even if the other such components, materials, elements, or method steps have the same function as the named ones.

[0042] It should also be understood that referring to one or more method steps does not preclude the existence of additional method steps or intermediate method steps between those explicitly identified steps. Similarly, it should be understood that referring to one or more components in an apparatus or system does not preclude the existence of additional components or intermediate components between those explicitly identified components.

[0043] The designs and functions described in this patent application are intended to be exemplary in nature and are not intended to limit this disclosure in any way. Those skilled in the art will understand that the teachings of this disclosure can be implemented in various suitable forms, including those disclosed herein and additional forms known to those skilled in the art.

[0044] While certain examples of this disclosure have been described in conjunction with what are now considered to be the most practical content and various examples, it should be understood that this disclosure is not limited to the disclosed examples, but rather is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims. Although specific terminology is used herein, it is used only in a general and descriptive sense and not for any purpose of limitation.

[0045] This written description uses examples to disclose certain examples of the technology and also enables any person skilled in the art to practice certain examples of the technology, including making and using any device or system and performing any of the included methods. The patentable scope of certain examples of the technology is defined in the claims and may include other examples that would occur to a person skilled in the art. Such other examples are intended to be within the scope of the claims if they have the same structural elements as the literal language of the claims, or if they include equivalent structural elements that are not substantially different from the literal language of the claims.

Claims

1. A vascular shunt system, comprising Vascular shunts, comprising: A tubular mesh frame, the tubular mesh frame comprising a mesh cover and openings, wherein: The tubular mesh frame is collapsible and configured to expand from a collapsed shape to a tubular shape when the vascular shunt is deployed; The mesh covering is conformable to the shape of the tubular mesh frame and is surrounded by the tubular mesh frame; The opening is located within the mesh cover; and The tubular mesh frame has more holes than the mesh cover; and Delivery device, the delivery device including a lumen housing the vascular shunt, the delivery device comprising: A microcatheter, comprising a tubular outer wall, a distal end, and a proximal end, wherein the distal end includes a transverse opening and a longitudinal opening, wherein the longitudinal opening intersects the transverse opening; and Delivery line, the delivery line including a distal segment, a proximal segment, and a connector located between the distal segment and the proximal segment, the connector being configured to push the vascular shunt, wherein: The distal segment has a smaller cross-section than the proximal segment; and The distal segment is maneuverable from the proximal end of the proximal segment, and at least a portion of the distal segment of the delivery line is configured to adopt a curved configuration.

2. The vascular shunt system of claim 1, wherein the tubular mesh frame has a circular cross-section.

3. The vascular shunt system of claim 1, wherein the mesh cover has a rounded periphery.

4. The vascular shunt system of claim 1, wherein the mesh cover has a circular periphery.

5. The vascular shunt system of claim 1, wherein the mesh cover is integral with the tubular mesh frame.

6. The vascular shunt system of claim 1, wherein the mesh cover is separate from and attached to the tubular mesh frame.

7. The vascular shunt system of claim 6, wherein the mesh cover is attached to the tubular mesh frame by welding.

8. The vascular shunt system of claim 1, wherein the mesh cover is attached to the tubular mesh frame by means of the mesh strands of the mesh cover interlacing with the mesh strands of the tubular mesh frame.

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