Patent Application
20230293184
The present invention relate to aneurysm treatment devices and more particularly, to improved delivery systems for embolic implants that prevent premature implant deployment.
Numerous intravascular implant devices are known in the field. Many are deployed mechanically, via systems that combine one or more catheters and wires for delivery. Examples of implants that can be delivered mechanically include embolic elements, stents, grafts, drug delivery implants, flow diverters, filters, stimulation leads, sensing leads, or other implantable structures delivered through a microcatheter. Some obstetric and gastrointestinal implants may also be implanted via similar systems that combine one or more catheters and wires. Devices that may be released or deployed by mechanical means vary greatly in design but can employ a similar delivery catheter and wire system. Many such catheter-based delivery systems include a wire for retention of the implant in the catheter until the time for release of the device. These systems are then actuated by retracting or pulling the wire relative to the catheter. Such a wire is referred to herein as a “pull wire”.
One issue with current catheter-based delivery systems is premature detachment of the implantable device. Premature detachment occurs when the implant is detached from the delivery system before reaching the treatment site. This may occur due to the tortuosity experienced by the delivery system as it passes through the vasculature of the patient, which can cause an increase in friction between the “pull wire” and the delivery system causing the pull wire to move proximally while the delivery system is moving distally.
Accordingly, there is a need for an improved implant delivery system that prevents premature detachment of the implant as it is delivered through tortuous vasculature. This disclosure is directed to this and other considerations.
Various systems and methods of delivering an implant are disclosed. A detachment system can include an outer tubular body defining a longitudinal axis that includes a first lumen, and an inner tubular body that includes a second lumen extending therethrough with the inner tubular body disposed within the first lumen. A pull wire can be at least partially within the second lumen and at least partially within the first lumen, and configured to translate in a proximal direction in relation to the outer tubular body to release the implant. A radial lumen can extend through the outer tubular body and inner tubular body orthogonal to the longitudinal axis. An interference feature can at least partially extend through the radial lumen to inhibit premature detachment of the implant. The interference feature can fracture in response to proximal translation of the inner tubular body to facilitate release of the implant.
In one aspect, a detachment system for delivering an implantable medical device to a target location of a body vessel is disclosed. The detachment system can include an outer tubular body that includes a first lumen that extends therethrough along a longitudinal axis. The detachment system can include an inner tubular body that includes a second lumen extending therethrough along the longitudinal axis. The inner tubular body can be disposed within the first lumen of the outer tubular body. The detachment system can include a pull wire that is disposed at least partially within the second lumen of the inner tubular body and at least partially within the first lumen of the outer tubular body. The pull wire can be configured to translate in a proximal direction in relation to the outer tubular body to release the implantable medical device from a distal end of the detachment system. The detachment system can include a radial lumen that extends through the outer tubular body and the inner tubular body orthogonal to the longitudinal axis. The detachment system can include an interference feature at least partially extending through the radial lumen. The interference feature can be effective to inhibit premature detachment of the implantable medical device as the implantable medical device is delivered by the detachment system to the target location of the body vessel. The interference feature can be configured to fracture in response to proximal translation of the inner tubular body to thereby facilitate release of the implantable medical device from the detachment system.
In some embodiments, the interference feature can include a monofilament suture.
In some embodiments, the interference feature is constructed of polypropylene 8-0.
In some embodiments, the interference feature is secured to an outer wall of the outer tubular body by a method selected from welding the interference feature to the outer wall, melting the interference feature to the outer wall, knotting the interference feature to the outer wall, and gluing the interference feature to the outer wall.
In some embodiments, the interference feature prevents proximal translation of the inner tubular body with respect to the outer tubular body.
In some embodiments, the proximal end of the pull wire can be attached to a proximal end of the inner tubular body. The pull wire can be configured to translate with the inner tubular body as a single unit in relation to the outer tubular body.
In some embodiments, the radial lumen can include an outer radial lumen and an inner radial lumen. The outer radial lumen can be in alignment with the inner radial lumen as the implantable medical device is delivered by the detachment system to the target location of the body vessel. The inner radial lumen can be configured to move out of alignment with respect to the outer radial lumen to thereby fracture the interference feature and facilitate release of the implantable medical device from the detachment system.
In some embodiments, the interference feature can extend through an entire length of the radial lumen and the interference feature can be secured to an outer wall of the outer tubular body at each end of the radial lumen.
In some embodiments, the interference feature is configured to fracture in response to a force between approximately 50 gram-force and approximately 100 gram-force.
In some embodiments, the detachment system can further include a loop wire that includes a loop opening that is positioned approximate a distal end of the outer tubular body. The loop wire and the pull wire can be positioned to secure the implantable medical device to the delivery system.
In some embodiments, the outer tubular body can further include a compressed distal portion that is held in compression by tension in the loop wire and the can be configured to provide a force distally to the implantable medical device upon release of the implantable medical device from the distal end of the detachment system.
In another aspect a method is disclosed. The method can include providing an outer tubular body that includes a first lumen extending therethrough along a longitudinal axis. The method can include providing an inner tubular body including a second lumen extending therethrough along the longitudinal axis. The method can include positioning the inner tubular body within the first lumen of the outer tubular body. The method can include forming a radial lumen that can extend radially through the outer tubular body and the inner tubular body orthogonal to the longitudinal axis. A pull wire can be extended through the second lumen of the inner tubular body and into the first lumen of the tubular body. A proximal end of the pull wire can be secured to a proximal end of the inner tubular body. An interference feature can be extended at least partially through the radial lumen such that the interference feature extends through an outer wall of the outer tubular body and an inner wall of the inner tubular body. The method can include securing an implantable medical device to the outer tubular body such that proximal translation of the pull wire can release the implantable medical device from the outer tubular body. The method can include preventing, with the interference feature, release of the implantable medical device while the implantable medical device is delivered through vasculature to a treatment site. The method can include translating the inner tubular body proximally to thereby fracture the interference feature and facilitate release of the implantable medical device from the detachment system.
In some embodiments, the radial lumen can include an outer radial lumen and an inner radial lumen. The outer radial lumen can be in alignment with the inner radial lumen as the implantable medical device is delivered by the detachment system to the target location of the body vessel. The inner radial lumen can be configured to move out of alignment with respect to the outer radial lumen to thereby fracture the interference feature and facilitate release of the implantable medical device from the detachment system.
In some embodiments, the method can include affixing a loop wire to the outer tubular body and positioning a loop opening in the loop wire approximate a distal end of the outer tubular body and through a locking portion of the implantable medical device.
In some embodiments, the interference feature can be configured to fracture in response to a force between approximately 50 gram-force and approximately 100 gram-force.
In some embodiments, the method can include preventing proximal translation of the inner tubular body with respect to the outer tubular body while the implantable medical device is delivered through vasculature to the treatment site.
In some embodiments, the method can include securing the interference feature to the outer wall of the outer tubular body using a method selected from welding the interference feature to the outer wall, melting the interference feature to the outer wall, knotting the interference feature to the outer wall, and gluing the interference feature to the outer wall.
In some embodiments, extending the interference feature through the radial lumen can include extending a body of the interference feature through an entire length of the radial lumen and attaching first and second ends of the interference feature to the outer wall at respective ends of the radial lumen.
In some embodiments, the body of the interference feature can be a monofilament suture.
In some embodiments, the pull wire can translate proximally with the inner tubular body as a single unit.
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.
The following description of certain examples of the invention should not be used to limit the scope of the present invention. The drawings, which are not necessarily to scale, depict selected embodiments and are not intended to limit the scope of the invention. The detailed description illustrates by way of example, not by way of limitation, the principles of the invention. Other examples, features, aspects, embodiments, and advantages of the invention will become apparent to those skilled in the pertinent art from the following description, which is by way of illustration, one of the best modes contemplated for carrying out the invention. As will be realized, the invention is capable of other different or equivalent aspects, all without departing from the invention. Accordingly, the drawings and descriptions should be regarded as illustrative in nature and not restrictive.
Any one or more of the teachings, expressions, versions, examples, etc. described herein may be combined with any one or more of the other teachings, expressions, versions, examples, etc. that are described herein. The following-described teachings, expressions, versions, examples, etc. should therefore not be viewed in isolation relative to each other. Various suitable ways in which the teachings herein may be combined will be readily apparent to those skilled in the pertinent art in view of the teachings herein. Such modifications and variations are intended to be included within the scope of the claims.
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 ±10% of the recited value, e.g. “about 90%” may refer to the range of values from 81% to 99%. In addition, as used herein, the terms “patient,” “host,” “user,” and “subject” refer to any human or animal subject and are not intended to limit the systems or methods to human use, although use of the subject invention in a human patient represents a preferred embodiment.
Turning to the figures,
Respective proximal ends of a loop wire 400 can be attached to the outer tubular body 90 of the detachment system 10. Disposed at a distal end of loop wire 400 can be a loop opening 405. Loop opening 405 can be passed through a locking portion 18 (e.g., aperture) of an implantable medical device 12. After loop opening 405 is positioned through locking portion 18, a distal end 144 of pull wire 140 can be positioned through the loop opening 405, thereby securing the implantable medical device 12 to the detachment system 10. Just distal of where respective proximal ends of loop wire 400 are attached to the outer tubular body 90, the outer tubular body 90 can include a compressed distal portion 300. The compressed distal portion 300 can be formed from spiral-cuts 306 formed in the outer tubular body 90, which can be formed by a laser cutting operation. Additionally, or alternatively, the compressible distal portion 300 can be formed of a wound wire, spiral ribbon, or other arrangement allowing axial adjustment according to the present invention. Preferably, compressible distal portion 300 is in the elongated condition at rest and automatically or resiliently returns to the elongated condition from a compressed condition, unless otherwise constrained. In some embodiments, the implantable medical device 12 can be an embolic coil.
Disposed orthogonally to the longitudinal axis L-L can be a radial lumen 150 that extends through the outer tubular body 90 and the inner tubular body 190. For example, the radial lumen can be formed by creating apertures within an outer tubular body wall 96 of outer tubular body 90 and inner tubular body 190 such that radial lumen 150 runs through respective lumens 708, 712. Radial lumen 150 can include an outer radial lumen 152 and an inner radial lumen 154, which are in alignment and collectively form radial lumen 150 while the detachment system 10 is delivered to a treatment site, as shown in
Now turning to
As shown in
The compressible portion 306 can have a difference in length (distance of compression) when measured in the compressed configuration and the original, uncompressed configuration of about 0.5 mm to about 0.75 mm. Greater elastic force E can be achieved by using a greater distance of compression. The distance of compression can be determined by the sizing of the loop wire 400, the shape of the locking portion 18, and the shape of the distal end 304 of the compressible distal portion 300.
In block 616, the method can include providing an inner tubular body 190. Inner tubular body can include a second lumen extending therethrough along the longitudinal axis L-L. In block 620, the method can include positioning the inner tubular body 190 within the first lumen 708 of the outer tubular body 90. In block 624, the method can include forming a radial lumen 150 that extends radially through the outer tubular body 90 and the inner tubular body 190. The radial lumen can be disposed orthogonal to the longitudinal axis L-L.
In block 628, a pull wire can be extended through the second lumen 712 of the inner tubular body 190 and into the first lumen 708 of the outer tubular body 90. In block 632, a proximal end 142 of the pull wire 140 can be secured to a proximal end 192 of the inner tubular body 190. As discussed, the pull wire can be attached to the tubular body 190 using any method known to a person having skill in the pertinent art, for example by welding or gluing the proximal end 142 of the pull wire 140 to the proximal end 192 of the inner tubular body 190.
In block 636, an interference feature 210a, 210b can be extended at least partially through the radial lumen 150. The interference feature can extend through an outer wall 96 of the outer tubular body 90 and an inner wall 196 of the inner tubular body 90.
In block 640, an implantable medical device 12 can be secured to the outer tubular body such that proximal translation of the pull wire can release the implantable medical device from the outer tubular body 90.
In block 644, the interference feature can prevent release of the implantable medical device while the implantable medical device 12 is delivered through the vasculature to a treatment site. In block 648, the method can include translating the inner tubular body 190 proximally, thereby fracturing the interference feature 210a, 210b and facilitating release of the implantable medical device 12 from the detachment system 10.
According to some embodiments, the radial lumen can include an outer radial lumen 152 and an inner radial lumen 154. The outer radial lumen 152 can be in alignment with the inner radial lumen 154 as the implantable medical device 12 is delivered by the detachment system 10 to the target location of the body vessel. The inner radial lumen 154 can be configured to move out of alignment with respect to the outer radial lumen 152 to thereby fracture the interference feature 150 and facilitate release of the implantable medical device from the detachment system 10.
According to some embodiments, the interference feature 210a, 210b is configured to fracture in response to a force between approximately 50 gram-force and approximately 100 gram-force.
According to some embodiments, the method can include preventing proximal translation of the inner tubular body 190 with respect to the outer tubular body 90 while the implantable medical device 12 is delivered through vasculature to the treatment site.
According to some embodiments, securing the interference feature 210a, 210b to the outer wall 96 of the outer tubular body 90 using a method selected from welding the interference feature 210a, 210b to the outer wall 96, melting the interference feature 210a, 210b to the outer wall, knotting the interference feature 210a, 210b to the outer wall 96, and gluing the interference feature to the outer wall 96.
According to some embodiments, extending the interference feature 210a, 210b through the radial lumen 150 can further include extending a body 216 of the interference feature 210a, 210b through an entire length L1 of the radial lumen 150 and attaching first and second ends 212, 214 of the interference feature 210a, 210b to the outer wall 96 at respective ends of the radial lumen 150.
According to some embodiments, the body 216 of the interference feature 210a, 210b can be a monofilament suture. According to some embodiments, the pull wire 140 translates proximally with the inner tubular body 190 as a single unit.
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 implantation system and associated methods, including alternative geometries of system components, alternative materials, additional or alternative method steps, etc. Modifications apparent to those skilled in the pertinent art are intended to be within the scope of the claims which follow.
