During catheter procedures, which may include angioplasty or atherectomy, medical catheters often pass through tortuous paths of body lumens. During passage various forces may need to be applied to the medical catheter to deliver it to a target site and perform a desired procedure. In some cases, a medical catheter may be inserted into a patient's body through a hemostatic support catheter, and this can result in relative friction between the support catheter and the medical catheter and therefore increase the force required to advance the medical catheter to a target site. In addition, medical catheters sometimes include fragile components such as fiber optics, electrical components, thin walled tubing or the like. As such, when a user of a medical catheter is performing a procedure, the user can sometimes deform a shaft of the medical catheter while applying the forces required to advance the medical catheter to the target site. Such deformation may, in turn, lead to reduced performance of the medical catheter in certain circumstances. What have been needed are devices and methods which allow a user of a medical catheter to position the medical catheter at a target site without deforming the medical catheter shaft or components disposed within the shaft of the medical catheter. What have been needed are devices and methods that allow a medical catheter having a liquid filled waveguide to withstand the forces required to position the medical catheter while minimizing undesired bulk to the outer profile of the medical catheter.
Some embodiments of a laser ablation catheter that may be used to ablate blockages as well as performing atherectomy in body lumens using high energy and high-power ultraviolet (UV) laser pulses may include a liquid filled waveguide. The liquid filled waveguide may include a catheter tube having an inner layer with a first index of refraction and an optical fluid that may be biocompatible and ultraviolet light transparent disposed within and completely filling an inner lumen of the catheter tube. The optical fluid may have a second index of refraction which is greater than the first index of refraction. The laser ablation catheter may also include a distal optical window which may be ultraviolet grade and elongated in configuration and which may be disposed in liquid sealed relation to a surface of the catheter tube at a distal end of the catheter tube. The distal optical window may also be disposed in optical communication with the optical fluid. The laser ablation catheter may also include a proximal optical window which is disposed in a liquid sealed relation to a surface of the catheter tube at a proximal end of the catheter tube. The proximal optical window may also be in optical communication with the optical fluid. The laser ablation catheter embodiment may further include an outer jacket that is disposed over the outer surface of the catheter tube with a proximal end that is disposed at a proximal portion of the catheter tube and a distal end that is disposed at a distal end of the catheter tube. The outer jacket may be secured relative to the catheter tube such that the outer jacket remains substantially fixed along a longitudinal axis thereof relative to the catheter tube. The outer jacket may also have a tubular configuration having an inner lumen with an inner surface, with the inner surface of the inner lumen being configured to slide over an exterior surface of the catheter tube with a close fit therebetween. The outer jacket may also include a tubular jacket body that includes an inner jacket layer comprised of a first material and an outer jacket layer comprised of a second material with the second material being different than the first material. The outer jacket may optionally have a longitudinal stiffness that is greater than a longitudinal stiffness of the catheter tube at the proximal portion of the catheter tube. The outer jacket may also include a reinforcement which is crush resistant and which may optionally be disposed between the inner jacket layer and the outer jacket layer of the tubular jacket body. In some cases, the tubular jacket body and reinforcement may be configured to increase the stiffness and crush resistance of the laser ablation catheter.
Some embodiments of a laser ablation catheter may include a liquid filled waveguide having a catheter tube with an inner layer with a first index of refraction and an optical fluid disposed within and completely filling an inner lumen of the catheter tube. The optical fluid may have a second index of refraction which is greater than the first index of refraction. A distal optical window may be disposed in optical communication with the optical fluid and disposed in sealed relation to an inner surface of the catheter tube at a distal end of the catheter tube. The liquid filled waveguide may also include a proximal optical window which is disposed in optical communication with the optical fluid and which is also disposed in a liquid sealed relation to the inner surface of the catheter tube at a proximal end of the catheter tube. The laser ablation catheter embodiment may also include an outer jacket which is disposed over an outer surface of the catheter tube. The outer jacket may have a proximal end that is disposed at a proximal portion of the catheter tube and a distal end that is disposed at a distal end of the catheter tube. In some instances, the outer jacket may include a tubular configuration having an inner lumen with an inner surface. The inner surface of the inner lumen of the outer jacket may be configured to slide over an outer surface of the catheter tube with a close fit therebetween. The outer jacket may also have a tubular jacket body that includes a longitudinal stiffness greater than a proximal portion of the catheter tube. The tubular jacket body may also include an inner jacket layer comprised of a first material and an outer jacket layer comprised of a second material. The outer jacket may also have a reinforcement that is crush resistant and disposed between the first layer and second layer of the tubular jacket body. An eccentric guidewire lumen may be disposed adjacent an outer surface of the outer jacket. For some embodiments, the eccentric guidewire lumen may have a proximal port and a distal port. The distal port may be disposed adjacent the distal end of the laser ablation catheter. The laser ablation catheter may also have a distal housing with a primary lumen which has a longitudinal axis that is concentric with a longitudinal axis of the catheter tube. The primary lumen may also be configured to accommodate the distal optical window. The distal housing may also have an eccentric passage which is disposed adjacent the primary lumen and which is configured to accommodate the eccentric guidewire lumen.
Some embodiments of a laser ablation catheter may include a liquid filled waveguide having a catheter tube with an inner layer with a first index of refraction and an optical fluid disposed within and completely filling an inner lumen of the catheter tube. The optical fluid may have a second index of refraction which is greater than the first index of refraction. The liquid filled waveguide may further have a distal optical window in optical communication with the optical fluid and disposed in sealed relation to an inner surface of the catheter tube at a distal end of the catheter tube. A proximal optical window may further be in optical communication with the optical fluid and disposed in a liquid sealed relation to the inner surface of the catheter tube at a proximal end of the catheter tube. The laser ablation catheter may also have an outer jacket that is disposed over an outer surface of the catheter tube. A proximal end of the outer jacket may be disposed at a proximal portion of the catheter tube and a distal end of the outer jacket may be disposed at a distal end of the catheter tube. For some embodiments, the outer jacket may include a tubular configuration having an inner lumen with an inner surface, the inner surface of the inner lumen being configured to slide over an outer surface of the catheter tube with a close fit therebetween. The outer jacket may also have a tubular jacket body with a longitudinal stiffness greater than a proximal portion of the catheter tube. The tubular jacket body may have an inner jacket layer including a first material and an outer jacket layer including a second material. The tubular jacket body may also have a reinforcement that is crush resistant and disposed between the first layer and second layer of the tubular jacket body.
Certain embodiments are described further in the following description, examples, claims and drawings. These features of embodiments will become more apparent from the following detailed description when taken in conjunction with the accompanying exemplary drawings.
The drawings are intended to illustrate certain exemplary embodiments and are not limiting. For clarity and ease of illustration, the drawings may not be made to scale, and, in some instances, various aspects may be shown exaggerated or enlarged to facilitate an understanding of particular embodiments.
Laser system embodiments discussed herein may generally include a laser which is configured to supply laser energy to a laser ablation catheter which may be operatively coupled to the laser. Such laser ablation catheter embodiments may be disposable in some cases and include a liquid core waveguide used to transmit the laser energy produced by the laser and coupled to the waveguide of the laser ablation catheter. Laser ablation catheters that include liquid core waveguides may sometimes have a low index of refraction coating which may be applied to an inner surface of a fluoropolymer catheter tube of the laser ablation catheter embodiments to yield high levels of transmission of laser energy through an optical fluid disposed within the catheter tube. In some cases, suitable laser energy for use with the laser ablation catheter embodiments discussed herein may have a wavelength in the ultraviolet range and in some particular cases may have a wavelength of about 308 nm. The laser energy may be pulsed as well.
Examples of laser system embodiments and associated laser ablation catheter embodiments are discussed in commonly owned U.S. Pat. No. 9,700,655, filed Oct. 12, 2012, by J. Laudenslager et al. and issued Jul. 11, 2017, titled “Small Flexible Liquid Core Catheter for Laser Ablation in Body Lumens and Methods for Use”, U.S. Patent Publication No. 2015/0105714, serial no. 14/515,435, filed Oct. 15, 2014, by J. Laudenslager et al., titled “Methods and Devices for Treatment of Stenosis of Arteriovenous Fistula Shunts”, now U.S. Pat. No. 9,962,527, issued May 8, 2018, U.S. Patent Publication No. 2017/0143424, serial no. 15/359,412, filed Nov. 22, 2016, by J. Laudenslager et al., titled “Laser Ablation Catheters Having Expanded Distal Tip Windows for Efficient Tissue Ablation,” now U.S. Pat. No. 10,555,772, issued Feb. 11, 2020, and U.S. Patent Publication No. 2019/0290356, serial no. 16/359,889, filed Mar. 20, 2019, by Z. Wood et al., titled “Liquid Filled Ablation Catheter with Overjacket,” each of which is incorporated by reference herein in its entirety.
Fluoropolymers such as fluorinated ethylene propylene (FEP), ethylene-tetrafluoroethylene-hexafluoropropylene (EFEP), ethylene tetrafluoroethylene (ETFE) and others may be desirable for use as catheter tubing material in these types of liquid core waveguide applications because catheter tubing formed from these materials may have a high UV transmission and low index or refraction amorphous Teflon AF® coatings may adhere well to such fluoropolymers. In addition, such fluoropolymer catheter tubes may be configured to be very flexible when axial loads are applied to laser ablation catheter embodiments that include catheter tubes made from such materials. As discussed above, catheter tubes which are formed from these materials may be coated with low index of refraction optical coatings in order to create an inner layer on the inner surface of the catheter tube. For some embodiments, the inner layer may have a first index of refraction and an optical fluid disposed within an inner lumen of such catheter tubes may have a second index of refraction which is greater than the first index of refraction resulting in internal reflection at the inner layer and thereby forming a waveguide with a tubular configuration which may be configured for transmission of high energy laser energy through the optical fluid.
In some cases, an optical coating in liquid form may be applied to the inner surface of the catheter tube, and then the optical coating may be thermally “cured” onto the inner surface via an appropriate thermal cycle thereby creating the inner layer. For some embodiments, this thermal cycle may be performed at elevated temperatures. In some instances, such elevated temperatures may possibly degrade and/or distort laser catheter components fabricated from non-fluoropolymer materials whereby physical distortion or softening of the materials may occur due to the high temperatures imposed on these materials. For this reason, it may be useful to perform such thermal cycle embodiments on the catheter tube and the optical coating prior to the addition of any other components of the corresponding laser ablation catheter which may include non-fluoropolymer polymer materials or metals of the laser ablation catheter which may be degraded by the thermal cycle.
Additionally, in some cases, the surface properties of the inner surface of a catheter tube which is formed from a fluoropolymer material may need to be altered in order to improve the adhesion of the optical coating to the inner surface. For example, the inner surface of the catheter tube may be chemically etched, plasma etched, or the like in order to obtain a desired level of adhesion between the catheter tube inner surface and the inner layer optical coating after the curing process.
As discussed above, a catheter tube which is formed from fluoropolymer material may exhibit suitable flexible behavior when subjected to axial loads, the flexibility of the catheter tube allowing for advancement of the respective laser ablation catheter through potential tortuous paths of body lumens of a patient or the like during a catheter procedure. In some cases, however, the flexibility of the catheter tube material may lead to distortion of the catheter tube which may in turn decrease the optical performance of the laser ablation catheter.
Distortion of the catheter tube may occur when a user of the laser ablation catheter applies an inward radial load to the catheter tube during manipulation of the catheter (e.g., fingers distorting/crushing an outside surface of the catheter tube while gripping the laser ablation catheter). In some other cases, distortion of the catheter tube may occur during advancement of the laser ablation catheter through a tortuous path, at which time an axial load is applied to the catheter tube. The axial load may lead to the distortion/kinking of the catheter tube due to insufficient longitudinal stiffness of the catheter tube during advancement through the tortuous path.
It may therefore be useful in some instances to implement devices and methods which increase the longitudinal stiffness and/or crush resistance of the catheter tube in order to avoid distortion of the catheter tube during a laser ablation catheter procedure. Currently some balloon catheters, fiber optic ablation catheters, and atherectomy catheters utilize guidewires which are operatively coupled to the respective catheter in order to increase the longitudinal stiffness and tractability of the catheter. Additionally, support catheters may be used to support these catheters.
For some laser ablation catheter embodiments that include a liquid core waveguide, a guidewire disposed through a central lumen of the catheter tube would significantly decrease the optical performance of the laser ablation catheter. The placement of an additional guidewire lumen in the center of the catheter tube may eliminate or greatly reduce the ability of the catheter to transmit laser energy by total internal reflection. For this reason, it may be useful for the longitudinal stiffness of the catheter tube to be optimized or improved through other means.
For some laser ablation catheter embodiments, the longitudinal stiffness of the catheter may be increased with the addition of an outer jacket which may be operatively coupled to the catheter tube waveguide portion of the laser ablation catheter. The outer jacket may be configured such that it slides over the outer surface of the catheter tube and includes a longitudinal stiffness which is greater than a longitudinal stiffness of the catheter tube in some cases. Such outer jacket embodiments may be configured to be resistant to radial loads (crush resistant) which are applied by a user of the laser ablation catheter. Because such outer jacket embodiments may be configured to slide over an outer surface of the catheter tube, the catheter tube and optical coating thereof may be exposed to an appropriate thermal cycle to form the inner layer and resulting optical waveguide properties prior to the attachment of the outer jacket. Thus, the outer jacket may include materials which would otherwise be degraded and/or distorted during application of the thermal cycle to the catheter tube and optical coating.
As discussed above, some laser ablation catheter embodiments discussed herein may be configured to allow for the optical coating and catheter tube to be thermally cycled and subsequently tested prior to the addition of an outer jacket. Thus, the material and/or materials of the outer jacket do not need to be subjected to the thermal cycle and can therefore be appropriately chosen and configured for their mechanical properties such that the outer jacket increases the longitudinal stiffness and crush resistance of the laser ablation catheter without degrading the properties of the finishes of the laser ablation catheter. This process also allows the material and/or materials of the outer jacket 14 to be selected in order to improve properties other than mechanical properties, such as radiation sterilization compatibility and the like.
An embodiment of a laser system 10 including a laser ablation catheter 12 that may be used for tissue ablation, atherectomy as well as other indications is shown in
The laser ablation catheter 12 may include a laser coupler 26 which is disposed at a proximal end 23 of the laser ablation catheter 12 and which is configured to be operatively coupled to the output coupler 22 of the laser system 10. The laser coupler 26 may be configured to reliably position a laser energy input of the laser ablation catheter 12 relative to the output coupler 22 in order to facilitate an effective coupling of the laser energy 21 generated by the laser source 11 into the laser ablation catheter 12 as shown in
In some cases, the laser system 10 may optionally include a support catheter 24 which may have an inner lumen that is configured to readily slide over an outer surface of the laser ablation catheter 12. The laser ablation catheter 12 may thus be configured to readily slide axially back and forth within the inner lumen of the support catheter 24 as well. In some cases, the support catheter 24 may be configured to provide support and guidance to the laser ablation catheter 12 during a laser ablation procedure as shown in
The liquid filled waveguide may also include a biocompatible ultraviolet transparent optical fluid 34 which is disposed within and which completely fills the inner lumen 30 of the catheter tube 28. The optical fluid 34 may have a second index of refraction which is greater than the first index of refraction of the inner layer 32. The different indices of refraction of the materials at an optical boundary 36 disposed between the inner layer 32 and the optical fluid 34 may be configured to allow for total internal reflection at the optical boundary 36 thereby forming an optical waveguide and permitting propagation of high powered laser energy through the waveguide. It may be useful for suitable optical fluid embodiments to efficiently transmit high power laser energy having a wavelength in the UV spectrum and particularly laser energy at wavelengths of about 308 nm with low optical losses and without degradation of the optical fluid embodiment 34. Embodiments of suitable optical fluids 34 may include materials such as purified water, purified saline solutions and the like.
In some instances, the quality and/or efficiency of optical transmission through the waveguide may be dependent upon the surface quality of the optical boundary 36 as shown in
The laser ablation catheter 12 may also include an ultraviolet grade elongated distal optical window 40 as shown in
In some cases, the distal optical window 40 may be polished by conventional methods such as lapping or the like which may leave a square shaped edge disposed about the perimeter of the output surface as illustrated on the distal optical window embodiment 40 shown in
For some embodiments the distal optical window 40 may be disposed within embodiments of a distal housing 37 which may have a generally tubular configuration. The distal housing 37 may be secured to both the distal optical window 40 and to the catheter tube 28 by any suitable means such as adhesive bonding and may be formed from any suitable material including polymers and metals. Some distal housing embodiments, including distal housing embodiment 37′ discussed below, may be formed from a metal such as stainless steel, titanium or the like, and such embodiments may be secured to the distal optical window by crimping the distal housing 37′ to the distal optical window 40 and to the catheter tube 28. The distal housing 37′ when made from such metals may also serve as a radiopaque marker in some cases.
The laser ablation catheter 12 may also include a proximal optical window 46 (see
In some instances, the materials which form the respective components of the waveguide (including the catheter tube 28, the inner layer 32, and the optical fluid 34) may be chosen such that each material is not degraded by a thermal cycle which the waveguide may be subjected to during the formation of the inner layer 32 as discussed above. For example, the catheter tube 28 may be formed from FEP, a material which will easily endure a 204 degrees centigrade (for about a 120 minute duration in some cases) thermal cycle that may be useful to the “cure” an inner layer 32 which may in turn be formed from an amorphous Teflon AF®/Fluorinert FC-40® solution or such a solution using any other suitable solvent in place of the Fluorinert FC-40 solvent as well. However, in some cases and for some indications, catheter tubes 12 formed from thermally suitable materials such as FEP may lack the longitudinal stiffness and crush resistance which are desirable in order to minimize/avoid distortion/optical damage to the waveguide during a procedure using the laser ablation catheter 12. In some cases, the catheter tube 28 may also be made from or include fluoropolymers such as ETFE. For some embodiments, the addition of an outer jacket 14 to the catheter tube 28 of the laser ablation catheter 12 may allow for the separate processing of some waveguide components (including the catheter tube 28 and inner layer 32) and add longitudinal stiffness and crush resistance to the structure of the laser ablation catheter.
Referring to
In some cases, the catheter tube 28 may have an axial length 70 (see
With regard to the interface between the catheter tube 28 and outer jacket 14 with the laser coupler 26, and referring to
Referring to
As shown in
In some cases, the distal end 44 or distal portion 61 of the catheter tube 28 may be secured to the distal optical window 40, or an outer surface thereof, with an adhesive bond and with a distal end 44 of the catheter tube 28 disposed proximally of the distal end 45 of the distal optical window 40 as shown in
Still referring to
For such embodiments, the distal housing 37′ may be secured to the catheter tube 28 with a distal end 39′ of the distal housing 37′ disposed proximally of the distal end 45 of the distal optical window 40. In some cases, the distal end 39′ of the distal housing 37′ may be disposed about 0.05mm to about 0.5 mm proximally of the distal end 45 of the distal optical window 40. In some cases, the catheter tube 28 may be secured to the distal optical window 40 with the distal end 44 of the catheter tube 28 disposed proximally of the distal end 45 of the distal optical window 40. In some instances, the distal end 44 of the catheter tube 28 is disposed about 2 mm to about 3 mm proximally from the distal end 45 of the distal optical window 40.
In some cases, the distal end 56 of the outer jacket 14 may be secured to the outside surface of a distal portion 61 of the catheter tube 28 with the distal end 56 of the outer jacket 14 disposed proximally of the distal end 44 of the catheter tube 28. Some embodiments may have the distal end 56 of the outer jacket 14 disposed under an inside surface of the proximal stepped section 41′ and crimped in place as shown in the embodiment of
In some instances, the distal end 56 of the outer jacket 14 may be disposed about 1 mm to about 2 mm proximally of the distal end 44 of the catheter tube 28. For some embodiments, the outer jacket 14 may be secured to the catheter tube 28 with an adhesive bond. For some embodiments, the outer surface of the outer jacket 14 may be configured to taper distally to a reduced outer transverse dimension at the distal end 56 of the outer jacket 14. For some embodiments, a radiopaque marker band 47′ may be disposed on an outside surface of the distal optical window 40 and inside the stepped inner lumen of the proximal section 41′ of the distal housing 37′ as shown in the embodiment of FIG. B. In some cases, a proximal end of the radiopaque marker band 47′ may be disposed adjacent the distal end 44 of the catheter tube 28. For some embodiments, the crimpable metal of the distal housing 37′ may include titanium, stainless steel or any other suitable crimpable metal or alloy.
Regarding the construction of certain embodiments of the outer jacket 14, some outer jacket embodiments 14 which are discussed herein may include a manipulation section 49 (see
For some embodiments, the manipulation section 49 may have a proximal terminus 55 (see
The laser ablation catheter 12 may also include a connector strain relief 82, and a jacket strain relief 84 (see
For some embodiments, the jacket strain relief 84 may be monolithically formed from a suitable resilient polymer material such as nylon, polyether block amides including Pebax®, polyurethanes including Pellathane®, silicone rubber, or the like. The jacket strain relief 84 may also be made from materials such as fluoropolymers including PCTFE, ETFE or the like which may be particularly resistant to certain sterilization methods such as radiation sterilization. Alternatively, the jacket strain relief 84 may be formed from multiple layers of materials including nylon and Pebax®. For some embodiments the jacket strain relief 84 may have an inner diameter 85 (see
In some cases, the outer jacket 14 may have a tubular configuration and may include an inner lumen 88 that has an inner surface 48. As discussed above, the inner lumen 88 (see
Referring to
The outer jacket 14 may include the tubular jacket body 68 that may optionally have a longitudinal stiffness greater than a longitudinal stiffness of the catheter tube 28 at the proximal portion 54 (see
In some cases, the outer jacket embodiment 14 may include a reinforcement 114 that is crush resistant and that is disposed along the tubular jacket body 68 as depicted in
In some cases, the reinforcement 114 may act to increase the hoop strength of the respective outer jacket 14. In general, the jacket body 68 and reinforcement 114 may also be configured in dimensions, materials, and features that increase the longitudinal stiffness and crush resistance of a respective laser ablation catheter embodiment 12. Some reinforcement embodiments 114 may include coils or braids which provide axial stiffness and crush resistance to the outer jacket 14, while still allowing for flexibility of the outer jacket 14 and respective laser ablation catheter 12 during an ablation procedure.
Referring again to
For some embodiments of the outer jacket 14, the first material of the inner jacket layer 138 may be made from a lubricious polymer such as a polyimide-PTFE hybrid material or may be made from polymers that include a lubricious low friction additive such as PTFE powders, FEP powders, HDPE powders and the like. In some cases, the lubricious low friction additive known by the trade name Mobilize manufactured by Compounding Solutions, 258 Goddard Road, Lewiston, Me. may be included with the first material of the inner jacket layer 138. For some embodiments, the first material of the inner jacket layer 138 and second material of the outer jacket layer 144 may include nylons, polyether block amides including Pebax®, polyurethanes including Pellethane® or the like. The first material of the inner jacket layer 138 and second material of the outer jacket layer 144 may also include fluoropolymers such as ETFE, PCTFE and the like. The Shore hardness of the first material and the second material, particularly those that include Pebax®, may be about 70D Shore hardness to about 74D Shore hardness in some cases. For some embodiments, portions of the inner jacket layer 138 may be thermally fused or adhesively bonded to respective portions of the outer jacket layer 144. Thus, the filament structure of the reinforcement 114 may be enclosed or otherwise encapsulated by material of the jacket body 116.
The reinforcement ribbon 174 may be formed from any suitable flexible resilient material, for example the reinforcement ribbon 174 could be formed from a metal such as stainless steel, superelastic alloys such as nickel titanium alloy or the like. For some embodiments the reinforcement ribbon 174 may be formed from a polymer such as polycarbonate, Kevlar® para-aramid synthetic fiber material or from any suitable natural protein fiber such as silk or the like.
In use, embodiments of the laser ablation catheter 12 may be guided to a suitable treatment site within a patient's body by a variety of techniques.
Such a procedure may be initiated by introducing a guide sheath into the patient's femoral artery, or any other suitable vessel access site, by methods such as the Seldinger technique or any other suitable method. A guidewire 35 (see
Any of the suitable laser ablation catheter embodiments discussed herein may include an eccentric guidewire lumen that may be used to slidingly accommodate a guidewire 35 that may be useful in some situations for guidance of suitable laser ablation catheter embodiments.
For the embodiment shown, the eccentric guidewire lumen 130 may include a nominal longitudinal axis 139 extending along a distal section of the laser ablation catheter 12′. In some cases, this nominal longitudinal axis 139 may be parallel to or substantially parallel to a longitudinal axis 140 of the catheter tube 28 (shown in
The distal housing 37″ also includes an eccentric passage 149 which is disposed adjacent to the primary lumen 148 and which is configured to accommodate the eccentric guidewire lumen 130 and components thereof such as the guidewire lumen sleeve 145 which may be disposed within eccentric passage 149. The guidewire lumen sleeve 145 may also terminate distally at a distal end of the eccentric passage 149 such that the respective distal ends of the guidewire lumen sleeve 145 and eccentric passage 149 are axially coextensive.
For some embodiments, the eccentric passage 149 may be disposed within an eccentric abutment structure 146 of the distal housing 37″. The eccentric abutment structure 146 extends radially outward from a nominal tubular surface surrounding the primary lumen 148 of the distal housing 37″. The distal housing 37″ may also optionally include a proximal cylindrical section 147 that is disposed proximal to the eccentric abutment structure 146 of the eccentric passage 149. The proximal cylindrical section 147 may have a generally circular outer cross section profile free of any eccentric abutment structure and may provide, in some circumstances, a symmetric cylindrical cross section that is amenable to inwardly crimping an outer surface thereof. The distal housing embodiment 37″ may be made from a crimpable material such as stainless steel, nickel titanium alloy, titanium, or the like.
In some cases, the eccentric passage 149 of the distal housing 37″ may have a discharge axis 139′ that may be angled towards the longitudinal axis 140 of the catheter tube and/or longitudinal axis 150 of the primary lumen 148. The discharge axis 139′ may include the longitudinal axis of the eccentric passage 149 of the distal housing 37″ irrespective of the orientation of the nominal longitudinal axis 139 of the eccentric guidewire lumen 130 disposed proximally of the distal housing 37″. That is, the angular orientation of the eccentric passage 149 may differ from the angular orientation of the nominal eccentric guidewire lumen 130. In some cases, wherein the nominal longitudinal axis 139 of the eccentric guidewire lumen 130 is parallel to the longitudinal axis 140 of the catheter tube 28, the discharge axis 139′ may form an angle 151 with the nominal longitudinal axis 139 of the eccentric guidewire lumen 130 of up to about 5 degrees. In some cases, the discharge axis 139′ may form an angle 151 with the nominal longitudinal axis 139 of the eccentric guidewire lumen 130 of up to about 2.5 degrees. In some cases, the discharge axis 139′ may form an angle 151 with the nominal longitudinal axis 139 of the eccentric guidewire lumen 130 of about 2 degrees to about 5 degrees.
In some instances, the distal port 134 of the eccentric guidewire lumen 130 may be disposed about 0 mm to about 2 mm proximally from the distal end 45 of the distal optical window 40 or about 0 mm to about 2 mm proximally from the distal end 136 of the laser ablation catheter 12′ generally. For some embodiments, the proximal port 132 may be disposed about 150 mm to about 400 mm proximally from the distal end 45 of the distal optical window 40 or from the distal end 136 of the laser ablation catheter 12′ generally. In some cases, the proximal port may be disposed about 150 mm to about 250 mm from the distal end 45 of the laser ablation catheter 12′, more specifically, about 150 mm to about 200 mm from the distal end 45 of the laser ablation catheter 12′.
For some embodiments, the eccentric guidewire lumen 130 may be surrounded by a guidewire lumen sleeve 145 that extends axially from the proximal port 132 to the distal port 134. The guidewire lumen sleeve 145 may be made from a low friction material which is secured to the outer jacket 14′ with a guidewire base 143 that may include a polymer or other material similar to that of the outer jacket layer 144 of the outer jacket 14′. The guidewire base 143 may serve to bond the guidewire lumen sleeve 145 to the outer jacket 14′ and provide a smooth outer contour at the junction between the guidewire lumen sleeve 145 and the outer jacket layer 144 of the outer jacket 14′.
As discussed above, laser ablation catheters embodiments which are configured with an outer jacket can be manufactured such that the waveguide and associated materials (catheter tube and the inner layer) may be thermally cycled separately from the other components of the laser ablation catheter embodiments. Thus, the laser ablation catheter 12 (or laser ablation catheter 12′) which is configured with an outer jacket 14 (or outer jacket 14′) may be made as follows. The inside surface 33 of the catheter tube 28 may be coated with an optical coating having a first index of refraction. An appropriate thermal cycle may then be applied to the catheter tube 28 and the optical coating to adhere the optical coating to the inner surface 33 of the catheter tube 28 thereby forming the inner layer 32.
An elongated distal optical window 40 may then be attached to a distal portion 61 of the catheter tube 28. The catheter tube 28 may then be filled with a biocompatible ultraviolet transparent optical fluid 34 having a second index of refraction. A high energy laser coupler 26 may then be attached to a proximal portion 54 of the catheter tube 28 with the laser coupler 26 having a laser coupler body, a window connector body being disposed within the optical coupler body, and the proximal optical window 46 disposed within and secured to the window connector body with the proximal optical window 46 being in optical communication with the optical fluid 34 as shown in
The outer jacket 14 may include the inner lumen 88 having the inner surface 48 which is configured to slide over an outer surface 50 of the catheter tube 28 with a close fit therebetween. In some cases, the close fit between the outer surface 50 of the catheter tube 28 and the inner surface 48 of the inner lumen 88 of the outer jacket 14 includes a dimensional clearance 98 (see
The outer jacket 14 or any other suitable outer jacket embodiment, such as outer jacket 14′, discussed herein may then be secured to the catheter tube 28 such that the outer jacket 14 remains substantially fixed in relation to the longitudinal axis 60 the catheter tube 28, with the outer jacket 14 being configured to increase the longitudinal stiffness and crush resistance of the laser ablation catheter 12. The proximal portion 74 of the outer jacket 14 may be adhesively bonded to the catheter tube 28 thereby forming the proximal bond section 78 utilizing any suitable adhesive 76 such as cyanoacrylate, epoxy, U.V. cured adhesives, or the like. The distal portion 64 of the outer jacket 14 may be adhesively bonded to the catheter tube 28 thereby forming a distal bond section 79 utilizing any suitable adhesive 76 such as cyanoacrylate, epoxy, U.V. cured adhesives or the like. For some embodiments the axial length 81 of the proximal bond section 78 may be about 0.039 inches to about 3 inches (see
Similar to the method description above with regard to use of laser catheter embodiment 12, in use, embodiments of the laser ablation catheter 12′ may be guided to a suitable treatment site within a patient's body by a variety of techniques.
As discussed above, such a procedure may be initiated by introducing a guide sheath into the patient's femoral artery, or any other suitable vessel access site, by methods such as the Seldinger technique or any other suitable method. The guidewire 35 which may be configured with a length, flexibility and outer diameter suitable for the intended indication, such as a coronary guidewire 35 may then be introduced into the guide sheath. Guidewire 35 may then be distally advanced through the guide sheath to the intended treatment site. The laser ablation catheter 12′ may then be distally advanced through the guide sheath and over the guidewire 35 with the guidewire 35 disposed within eccentric guidewire lumen 130 until the distal end of the laser ablation catheter 12′ is disposed adjacent the blockage 25 as shown in
Embodiments illustratively described herein suitably may be practiced in the absence of any element(s) not specifically disclosed herein. Thus, for example, in each instance herein any of the terms “comprising,” “consisting essentially of,” and “consisting of” may be replaced with either of the other two terms. The terms and expressions which have been employed are used as terms of description and not of limitation and use of such terms and expressions do not exclude any equivalents of the features shown and described or portions thereof, and various modifications are possible. The term “a” or “an” can refer to one of or a plurality of the elements it modifies (e.g., “a reagent” can mean one or more reagents) unless it is contextually clear either one of the elements or more than one of the elements is described. Thus, it should be understood that although embodiments have been specifically disclosed by representative embodiments and optional features, modification and variation of the concepts herein disclosed may be resorted to by those skilled in the art, and such modifications and variations are considered within the scope of this disclosure.
With regard to the above detailed description, like reference numerals used therein refer to like elements that may have the same or similar dimensions, materials and configurations. While particular forms of embodiments have been illustrated and described, it will be apparent that various modifications can be made without departing from the spirit and scope of the embodiments of the invention. Accordingly, it is not intended that the invention be limited by the forgoing detailed description.
This application is a national stage application under 35 U.S.C. section 371, which claims the benefit of priority to PCT Application No. PCT/US2021/019199, filed Feb. 23, 2021, by Brian MARSH et al., and titled “LASER ABLATION CATHETER WITH OUTER JACKET SUPPORT,” which claims priority from U.S. provisional patent application serial number 62/980,968 filed Feb. 24, 2020, by Brian MARSH et al., and titled “LIQUID FILLED LASER ABLATION CATHETER WITH FULL LENGTH OUTER JACKET SUPPORT”, each of which is incorporated by reference herein in its entirety.
Filing Document | Filing Date | Country | Kind |
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PCT/US2021/019199 | 2/23/2021 | WO |
Number | Date | Country | |
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62980968 | Feb 2020 | US |