MEDICAL DEVICE DELIVERY MEMBER WITH POSITIONING WINDOW
20220240977 · 2022-08-04
Assignee
Inventors
Cpc classification
A61M2025/0042
HUMAN NECESSITIES
A61B2017/12054
HUMAN NECESSITIES
A61B17/3468
HUMAN NECESSITIES
A61B2090/3966
HUMAN NECESSITIES
International classification
Abstract
A delivery member is provided for delivering and deploying an intravascular medical device. The delivery member includes a flexible distal portion including a wound wire coil surrounded by a flexible sleeve and inhibited from extending lengthwise by a support tube positioned through the lumen of the coil. The delivery member can include hypotubes positioned on either side (distally and proximally) from the wound wire coil to which the stretch resistant member and the wound wire coil can be attached. The distal hypotube can include attachment slots for positioning and attaching a loop wire to the distal hypotube. The distal hypotube can further include one or more tube windows for visualization of proper placement of the support tube within a lumen of the distal hypotube.
Claims
1. A delivery member comprising: a distal hypotube comprising: a distal end shaped to receive an implantable medical device; a longitudinal axis from the distal end to a proximal end of the distal hypotube; and a first tube window extending from a lumen of the distal hypotube to an outer surface of the distal hypotube, the first tube window having a length greater than a width, wherein the length is along the longitudinal axis; and a support tube positioned within the lumen of the distal hypotube.
2. The delivery member of claim 1, wherein a distal end of the support tube is positioned such that it is placed within the length of the first tube window and is visible external to the distal hypotube.
3. The delivery member of claim 1, further comprising: a loop wire extended through an opening in the implantable medical device; and a pull wire extended through the lumen, engaged to the loop wire, and movable to retract proximally to disengage the loop wire to deploy the implantable medical device.
4. The delivery member of claim 1, wherein the distal hypotube further comprises a first attachment slot extending from the lumen of the distal hypotube to the outer surface of the distal hypotube, wherein a first end of a loop wire extends at least partially through the first attachment slot.
5. The delivery member of claim 4, wherein the distal hypotube further comprises a second attachment slot extending from the lumen to the outer surface, wherein a second end of the loop wire extends at least partially through the second attachment slot, and wherein the first tube window is positioned proximal to the first attachment slot and the second attachment slot in relation to the distal end of the distal hypotube.
6. The delivery member of claim 1, wherein the length of the first tube window is from approximately 0.10 inches to 0.40 inches, and the width of the first tube window is from approximately 0.02 inches to 0.10 inches.
7. The delivery member of claim 1, wherein the length of the first tube window is from approximately 0.2 inches to 0.30 inches, the width of the first tube window is from approximately 0.035 inches to 0.86 inches.
8. The delivery member of claim 1, wherein the distal hypotube further comprises a spiral cut along the longitudinal axis, and wherein the first tube window is positioned between adjacent cuts of the spiral cut.
9. The delivery member of claim 1, wherein the distal hypotube further comprises a second tube window, and wherein the first tube window and the second tube window are positioned equidistant from the distal end of the distal hypotube.
10. The delivery member of claim 1, wherein a distal end of the first tube window is positioned approximately 22 mm from the distal end of the distal hypotube.
11. A method of manufacturing a delivery member for an implantable medical device, the method comprising: passing a support tube through a lumen of a flexible distal hypotube of the delivery member until a distal end of the support tube is positioned within a length of and viewable through a tube window of the flexible distal hypotube; affixing the support tube to the delivery member; and affixing a loop wire to the flexible distal hypotube, wherein the tube window has a length greater than a width, and wherein the length of the tube window is along a longitudinal axis passing through the lumen.
12. The method of claim 11, wherein affixing the loop wire to the flexible distal hypotube comprises: passing a first end of the loop wire through a proximal end of a first attachment slot of the flexible distal hypotube; pulling the first end of the loop wire from the proximal end of the first attachment slot toward a distal end of the first attachment slot, the distal end having a smaller diameter than the proximal end; attaching the loop wire to the first attachment slot; passing a second end of the loop wire through a proximal end of a second attachment slot of the flexible distal hypotube; pulling the second end of the loop wire from the proximal end of the second attachment slot toward a distal end of the second attachment slot, the distal end having a smaller diameter than the proximal end; and attaching the loop wire to the second attachment slot.
13. The method of claim 12, wherein the tube window is positioned proximal to the first attachment slot and the second attachment slot in relation to the distal end of the flexible distal hypotube.
14. The method of claim 11, further comprising forming the tube window in the flexible distal hypotube by cutting or etching the tube window between adjacent cuts of a spiral cut in the flexible distal hypotube.
15. The method of claim 11, wherein the length of the tube window is from approximately 0.10 inches to 0.40 inches, and the width of the tube window is from approximately 0.02 inches to 0.10 inches.
16. The method of claim 11, wherein the length of the tube window is from approximately 0.2 inches to 0.30 inches, the width of the tube window is from approximately 0.035 inches to 0.86 inches.
17. The method of claim 11, wherein a distal end of the tube window is positioned approximately 22 mm from the distal end of the flexible distal hypotube.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0046] The above and further aspects of this invention are further discussed with reference to the following description in conjunction with the accompanying drawings, in which like numerals indicate like structural elements and features in various figures. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating principles of the invention. The figures depict one or more implementations of the inventive devices, by way of example only, not by way of limitation.
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DETAILED DESCRIPTION
[0061] During an intravascular treatment, for instance, an aneurysm occlusion treatment, lack of flexibility of a distal portion of a treatment device delivery member can cause the delivery member to pull back from the treatment site or otherwise move out of position while an implant or other medical treatment device is being placed in an aneurysm or other treatment site. A delivery member and engagement system having a more flexible distal portion can therefore provide a stable system for delivering medical devices in neurovascular anatomy in addition to other applications facing a similar challenge. Flexible structures, however, can tend deform, extend, or expand when navigating tortuous anatomy. Deformation of the delivery member can inhibit the delivery member's ability to navigate to a treatment site and/or effectively deploy the medical device. Elongation of the delivery member can result in premature deployment of the medical device.
[0062] An object of the present invention is to provide a delivery member having a highly flexible distal portion that is stretch resistant and structurally stable throughout delivery and deployment of a medical treatment device. For ease of discussion, medical treatment devices are generally referred to herein as an “implant” although, as will be appreciated and understood by a person of ordinary skill in the art, aspects of the present invention can be applied to deliver and deploy medical treatment devices that are not left implanted.
[0063] According to the present invention, in some examples, the highly flexible distal portion of the delivery member can include a coiled wire, an outer sleeve, and an inner stretch resistant support tube. The coiled wire can be formed of a substantially linear wire that is wound in a coil shape and/or a hypotube that is laser cut in a spiral pattern. If the coiled wire is formed from a laser cut hypotube, the spiral can be absent interference cuts connecting windings in the coil so as to provide a more flexible coil. The outer sleeve can inhibit the coiled wire from deforming radially and/or provide a smooth surface against which vascular walls can slide during delivery of an implant. The stretch resistant support tube can inhibit elongation of the coiled wire during delivery of the implant. The combination of the coiled wire, outer sleeve, and stretch resistant support tube can therefore provide a distal portion of a delivery member having greater flexibility and greater stability than at least some known delivery members.
[0064] Turning to the figures, as illustrated in
[0065]
[0066] The coiled section 200 can be formed separately from the proximal hypotube 100 and/or the distal hypotube 300. The separately formed coiled section 200 can be affixed with welds 712, 714 or other appropriate attachment to the proximal tube 100 and/or the distal tube 300. Alternatively, or additionally, at least a portion of the coiled section can be formed from a spiral laser cut portion of a hypotube. A separately formed coiled section 200 can be made more flexible compared to a spiral cut tube by selecting a wire with a particular cross section (e.g. circular) with a particular diameter D, or by selecting a wire with material properties to increase flexibility. Conversely, a laser cut portion can be more easily fabricated by cutting a single hypotube to form the proximal tube 100, coiled section 200, and distal hypotube 300, reducing or eliminating welds 712, 714 or other attachments. In either case, the wire of the coil 200 can have a diameter D measuring within a range including about 0.8 mils and 5 mils (about 20 nm to about 130 nm).
[0067] The coiled section can be formed primarily of a non-radiopaque material such as steel and can include a radiopaque section 216 made of a radiopaque material such as platinum and/or tungsten. The radiopaque section 216 can be positioned between a proximal, non-radiopaque section of the coil 212 and a distal, non-radiopaque section of the coil 214. The radiopaque section 216 can be positioned a predetermined distance from a distal end 304 of the delivery member 10 so that a physician can readily visualize the placement of the distal portion of the delivery member during a treatment procedure. The proximal section 212, radiopaque section 216, and distal section 214 can be concentrically welded.
[0068] The coiled section 200 can be surrounded by a flexible sleeve or fused sleeve 500, referred generically herein as a “sleeve.” The sleeve 500 can inhibit the coil 200 from expanding radially and/or from engaging vascular walls during navigation. The sleeve 500 can include a polymer. The polymer can include additives to increase the lubricity of the sleeve 500 so that the sleeve can easily slide through a body vessel. As illustrated in
[0069] The stretch resistant support tube 600 can be positioned to inhibit elongation of the coil 200 during intravascular navigation. The stretch resistant support tube 600 can include a tube sized to fit within the lumen 208 of the coil 200. The stretch resistant tube 600 can also be sized to extend through the entirety of the length of the coil 200, extend with a lumen 108 of the proximal tube 100 and within the lumen 308 of the distal tube 300. The stretch resistant support tube 600 can be attached to the proximal tube 100 and the distal tube 300 at adhesive joints 702, 704 or other appropriate attachment. The stretch resistant support tube 600 can remain unattached to the coiled section 200 such that the stretch resistant support tube 600 and coiled section 200 are able to move independently from each other to some extent.
[0070] The delivery member 10 can include a mechanical engagement system for engaging a medical device 12 during delivery to a treatment site, and the delivery member 10 can be actuated mechanically to deploy the medical device 12. Mechanically actuated engagement systems can include one or more inner elongated members or pull wires extending through the delivery member that can be manipulated at the proximal end by a physician to deploy a medical treatment device. Such a wire or inner elongated member is referred to herein generically as a “pull wire.” When reference is made herein to an engagement system, the engagement system can include the combination of a loop wire 400 and a pull wire 140.
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[0073] The first attachment slot 310 can have a distal end 312 and a proximal end 314. As can be seen, a diameter 313 of the distal end 312 can be smaller than a diameter 315 of the proximal end 314 of the first attachment slot 310. This tapered (or teardrop) design can facilitate the attachment of the loop wire 400 to the distal hypotube 300. For example, if the proximal end 314 is larger in diameter, the loop wire 400 can be fed through more easily. Once through the larger proximal diameter 315, the loop wire 400 can be pulled toward the distal end (312) of the first attachment slot (310). In some examples, the transition between the proximal end 314 and the distal end 312 can be slightly tapered such that, as the loop wire 400 is pulled toward the distal end 312, the loop wire 400 can be wedged within the first attachment slot. The second attachment slot 316 can be similar in all regards to the first attachment slot 310. For example, the second attachment slot 316 can have a distal end 322 and a proximal end 324, and a diameter 323 of the distal end 322 can be smaller than a diameter 325 of the proximal end 324 of the second attachment slot 316.
[0074] When the loop wire 400 is fed through the attachment slot 310,316, and pulled toward the distal end 312,322, the loop wire 400 can be attached to the distal hypotube 300 via an attachment 408,409.
[0075] The first attachment 408 can be a weld that holds the loop wire 400 to the first attachment slot 310. In some examples, the loop wire 400 can comprise metallic materials, such as stainless steel, cobalt-chrome alloy, titanium, nickel-titanium alloy (nitinol), and the like. Similarly, the distal hypotube can comprise metallic materials, such as stainless steel, cobalt-chrome alloy, titanium, nitinol, and the like. This can enable the first attachment 408 to be a metallic weld attaching the loop wire 400 to the first attachment slot 310. In some examples, the loop wire 400 can comprise a polymer material, such as nylon, polypropylene, silk, polyester, and the like. The loop wire can include braided or monofilament wires. The first attachment 408 can be a thermoplastic weld at the first attachment slot 310.
[0076] Additionally, or alternatively, the first attachment 408 can be an epoxy holding the end of the loop wire 400 to the first attachment slot 408. As stated above, the second attachment slot 316 can include a second attachment 409 to attach the loop wire 400 to the second attachment slot 316. The second attachment 409 can be similar to the first attachment 408.
[0077] In some examples, the first attachment 408 can be a knot in the loop wire 400. As described above, the first attachment slot 310 can have a proximal end 314 that is larger in diameter than the distal end 312. The loop wire 400 can be pulled through the first attachment slot 310, tied into a knot, and then pulled toward the distal end 312. The knot can be larger than the distal diameter 313 so that the loop wire 400 cannot be pulled back through the first attachment slot 310 once a knot is tied in the loop wire 400. In other examples, the loop wire 400 can be tied into a knot first, then the knot can be fed through the proximal end of 314 of the first attachment slot 310, and then the loop wire 400 can be pulled toward the distal end 312. In these examples, a knot diameter can be approximately equal to the first diameter 315 of the first attachment slot 310. This would enable the loop wire 400 to be fed through the proximal end 314 but prohibit the loop wire 400 from being pulled through the distal end 312 of the first attachment slot 310. The second attachment 409 can similarly be a knot in the opposite end of the loop wire 400.
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[0083] The combination of the coil 200, sleeve 500, and stretch resistant support tube 600 can provide a highly flexible distal portion of a delivery member 10 suitable for navigating tortuous anatomy, including neurovascular blood vessels. The stretch resistant support tube 600 can support the coil 200 to prevent the coil 200 from significantly extending during navigation of a blood vessel, thereby reducing tension on a pull wire 140 extending therethrough and reducing the likelihood of premature deployment of an attached medical treatment device.
[0084] The proximal tube 100 can include a flexible section 106 having material removed to increase flexibility of the flexible section 106. The flexible section 106 can be cut in a spiral pattern. The spiral pattern of the flexible section 106 can lack interference cuts connecting windings within the spiral. The stretch resistant support tube 600 can extend through the flexible section 106 and be attached to the proximal tube 100 in the proximal direction from the flexible section 106. The stretch resistant support tube 600 can thereby inhibit elongation of the flexible section 106 of the proximal tube 100 and coiled section 200. The sleeve 500 can cover at least a portion of the flexible section 106 to inhibit deformation of the flexible section and/or reduce friction with vasculature and the flexible section 106 during intravascular navigation. In some examples, the sleeve 500 can cover about 10 cm of the proximal tube 100 approximate and/or including the distal end 104 of the proximal tube 100.
[0085] The distal hypotube 300 can include a compressible portion 306. The compressible portion 306 can be axially adjustable between an elongated condition and a compressed condition. The distal hypotube 300 can also be flexible such that the distal hypotube 300 can provide a stable system for delivering medical devices in neurovascular anatomy. The distal hypotube 300 can include a spiral cut 307, formed by a laser cutting operation for example, to create the compressible and/or flexible construct. Additionally, or alternatively, the compressible portion 306 can be formed of a wound wire, spiral ribbon, or other arrangement allowing axial adjustment according to the present invention. Preferably, the compressible portion 306 is in the elongated condition at rest and automatically or resiliently returns to the elongated condition from a compressed condition, unless otherwise constrained.
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[0087] Illustrations in the above-described figures depict generally hollow or tubular structures 100, 200, 300, 500, 600 according to the present invention. When used herein, the terms “tubular” and “tube” are to be construed broadly and are not limited to a structure that is a right cylinder or strictly circumferential in cross-section or of a uniform cross-section throughout its length. For example, the tubular structure or system is generally illustrated as a substantially right cylindrical structure. However, the tubular system may have a tapered or curved outer surface without departing from the scope of the present invention.
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[0089] In step 820, the stretch resistant member can be positioned in the lumen of the wire coil. In step 820, the stretch resistant member that is positioned can be substantially tubular. In step 830, the first hypotube, wire coil, and second hypotube can be attached to each other. In step 840, the stretch resistant member is attached to the first hypotube and the second hypotube. The first hypotube, wire coil, and second hypotube can be attached as illustrated and described herein or by other means as would be understood by a person of ordinary skill in the art. Steps 820, 830, and 840 need not be performed in that order and can be performed simultaneously. For instance, the stretch resistant member can be attached to one of the first and second hypotubes as indicated in step 840, then the hypotube to which the stretch resistant member is attached can be attached to the wire coil as indicated in step 830, then the stretch resistant member can be positioned through the wire coil as indicated in step 820, then the other of the hypotubes can be attached to the wire coil as indicated in step 830, then the stretch resistant member can be attached to that other hypotube as indicated in step 840.
[0090] In step 850, the wire coil can be covered with the flexible sleeve. The flexible sleeve can cover some or all of the outer surface of the wire coil. Step 850 can also include the step of fusing the flexible sleeve to the wire coil and/or otherwise affixing the flexible sleeve to the delivery member. If the second hypotube has a flexible section, in step 850, the flexible sleeve can also be positioned to cover at least a portion of the flexible section.
[0091] In step 860, an implant can be detachably attached to the distal end of the first hypotube. In step 860, the implant can be attached by positioning a loop wire within the first hypotube, positioning a pull wire to extend through the first hypotube, coiled wire, and second hypotube, and securing the implant with the loop wire and the pull wire. The pull wire can be extended from the proximal end of the second hypotube. If the first hypotube has a compressible portion, in step 860, the compressible portion can be compressed, and the implant can be attached to delivery member while the compressible portion is compressed.
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[0093] In step 920, the system can be moved through a catheter to a treatment site such as the site of an aneurysm or other abnormality in a blood vessel. In step 930, the system can be flexed as it is moved through the catheter. In step 940, the coiled section of the system can be prevented from deforming by the flexible sleeve and the stretch resistant member; the flexible sleeve can inhibit the coiled section from deforming radially while the stretch resistant member can inhibit the coil from extending longitudinally.
[0094] In step 950, the medical treatment device can be deployed. In the case that the medical treatment device is an implant, in step 950 the implant can be detached. In step 960, the distal tube can extend to push the medical treatment device away from the distal tube. In the case that the medical treatment device is an implant detached in step 950, in step 960, the detached implant can be ejected away from the distal tube in response to the expansion of the distal tube.
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[0096] In step 1040, the loop wire can be attached to the first attachment slot. This attachment can be made in a number of ways, as described herein. The loop wire can be welded to the first attachment slot. In other examples, the loop wire can be affixed to the first attachment slot via an epoxy. In other examples, the loop wire can include a knot tied into the first end of the loop wire. The knot can be tied prior to pulling the first end of the loop wire through the proximal end of the first attachment slot. In this case, the knot can be approximately the same size as the diameter of the proximal end of the first attachment slot. This can enable the knot to be fed through the proximal end but prohibit the knot from being pulled back through the distal end. The knot can be tied after pulling the first end of the loop wire through the proximal end of the first attachment slot. The knot can be larger than one or both of the proximal and the distal end of the first attachment slot so that the loop wire cannot be pulled back through the first attachment slot. The first end of the loop wire can be attached at the distal end of first attachment slot, or the first end of the loop wire can be attached at any other location in the first attachment slot that is narrower than the proximal end (see, for example,
[0097] In step 1050 through step 1070, the method steps outlined above for steps 1020 through 1040 can be repeated for a second attachment slot. For example, a second end of the loop wire can be positioned in a second attachment slot similar to the process described above for the first end of the loop wire and the first attachment slot.
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[0099] The placement of the support tube 600 can be important—as improper placement can lead to manufacturing difficulties. For example, if the support tube 600 is placed too proximal, proper support at the junction between the distal tube 300 and coiled section 200 may not be achieved; if the support tube 600 is placed too distal, the support tube 600 can interfere with the placement of the attachments (e.g., attachments 408,409) at the attachment slots (e.g., first attachment slot 310 and second attachment slot 316). The present disclosure provides a solution assist in placement of the support tube 600 by using one or more tube windows 720, as shown in
[0100] Referring to
[0101] In some examples, the delivery member 10 can include a second tube window 722, which can be similar to the first tube window 720, such that the position of the support tube 600 within the lumen 308 can be viewed at different angles. In examples with two tube windows, the first tube window 720 and the second tube window 722 can be positioned equidistant from the distal end 304 of the distal hypotube 300. Throughout this disclosure, when reference is made to a singular “tube window,” it can be referred to as “tube window 720”; but it will be appreciated that any description of a tube window 720 can apply equally to the first tube window or the second tube window 722. The tube window 720 can be formed into the distal hypotube 300 by cutting or etching the tube window 720 into the distal hypotube 300. In some examples, the tube window 720 can be cut or etched between adjacent cuts of a spiral cut 307 in the distal hypotube 300.
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[0106] At block 1110, method 1100 can include passing a support tube 600 through a lumen 308 of a flexible distal hypotube 300 of the delivery member 10. The support tube 600 can be advanced until a distal end 752 of the support tube 600 is positioned within a length (L) of and viewable through a tube window 720 of the flexible distal hypotube 300.
[0107] At block 1115, method 1100 can include affixing the support tube 600 to the delivery member 10. As described above, the support tube 600 can be affixed to the delivery member 10, for example via an adhesive that is placed between the support tube 600 and (i) the distal hypotube 300 and (ii) a coiled section 200 of the delivery member 10. At block 1120, method 110 can include affixing a loop wire 400 to the flexible distal hypotube 300. In some examples, the method of affixing the loop wire can be performed according to steps 1020 to 1070 described above with reference to
[0108] As used herein, the terms “about” or “approximately” for any numerical values or ranges indicate a suitable dimensional tolerance that allows the part or collection of components to function for its intended purpose as described herein. More specifically, “about” or “approximately” may refer to the range of values±20% of the recited value, e.g. “about 90%” may refer to the range of values from 71% to 99%.
[0109] The descriptions contained herein are examples of embodiments of the invention and are not intended in any way to limit the scope of the invention. As described herein, the invention contemplates many variations and modifications of the delivery system, delivery member, and engagement system, including alternative configurations of components, alternative materials, alternative medical treatment devices, alternative means for deploying the medical treatment device, alternative geometries of individual components, alternative means for attaching component parts, etc. These modifications would be apparent to those having ordinary skill in the art to which this invention relates and are intended to be within the scope of the claims which follow.