Patent Publication Number: US-2021170144-A1

Title: Centering coiled guide

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation of patent application Ser. No. 15/816,412, filed Nov. 17, 2017 and is a continuation and claims priority to patent application Ser. No. 14/518,545, filed Oct. 20, 2014, entitled CENTERING COILED GUIDE, now U.S. Pat. No. 9,839,766, issued Dec. 12, 2017 the entirety of which is incorporated herein by reference. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     n/a 
     FIELD OF THE INVENTION 
     The present invention relates to a method, device, and system for providing a lumen within a catheter body. The present invention further relates to a method, device, and system for providing a lumen within a catheter body that preserves the flexibility of the catheter body and that is centered within the catheter body. 
     BACKGROUND OF THE INVENTION 
     Catheters are medical devices commonly used for a variety of medical procedures and purposes, including cardiac ablation and treatment techniques. Typically, a catheter used for endocardial procedures include an elongate, flexible body that extends from the device handle. Not only is the flexible body sized to be positioned within the patient&#39;s vasculature, but the flexible body must also be flexible enough to be navigated through the patient&#39;s body and steerable enough to be positioned at the target treatment site. Therefore, the elongate body must contain the necessary device components, such as pull wires, shims, fluid delivery and recovery lumens, electrical wires, and others, depending on the type of the device. Consequently, an elongate body may need to include a plurality of lumens or channels therein to accommodate all these elements and, in many cases, keep them isolated from each other (for example, some components may need to be mechanically, fluidly, thermally, and/or electrically isolated from others). 
     Not surprisingly, these features may significantly add to the manufacturing cost of the catheter body and the device as a whole. Each type of catheter body must be designed and manufactured independently, with very few, if any, designs being a one-size-fits-all design. Additionally, including a plurality of lumens within the catheter body may not only take up valuable and limited space within the body, but may also decrease the overall flexibility and steerability of the body. 
     Therefore, it is desirable to provide a catheter body that includes a central lumen that can be used to center certain components, such as pull wires and guidewire lumens, and that also remains flexible. It is further desired to provide a device that can be incorporated into a simply manufactured catheter body (for example, an extruded tube) to provide these benefits and to reduce manufacturing costs. 
     SUMMARY OF THE INVENTION 
     The present invention advantageously provides a method, device, and system for providing a centered lumen within a catheter body. The present invention further relates to a method, device, and system for providing a lumen within a catheter body that preserves the flexibility of the catheter body and that is centered within the catheter body. A coiled guide lumen defining a longitudinal axis may include a length of wire forming a plurality of coils about the longitudinal axis, the plurality of coils having a variable outer diameter, the coiled guide being sized to be contained within a catheter elongate body, the coiled guide extending from a proximal portion of the catheter elongate body to a distal portion of the catheter elongate body. The plurality of coils may include a plurality of first sections each having a first outer diameter and a plurality of second sections each having a second outer diameter, the second diameter being greater than the first diameter. Each of the plurality of first sections may have a first length and each of the plurality of second sections may have a second length, the second length being greater than the first length. For example, each of the plurality of first sections may include between one and five coils. Alternatively, the first length may be greater than the second length. For example, each of the plurality of second sections may include between one and five coils. The plurality of coils may further include a transition section on each side of each of the plurality of second sections. Additionally, the coiled guide lumen may include a first end and a second end, with a first section being at each of the first end and second end. The wire may have a flat or round cross section. The coiled guide lumen may further include a secondary guide lumen that is passed through coils in the plurality of first sections, such that the secondary guide lumen and the coiled guide lumen are coaxial. The secondary guide lumen may be composed of a material having a low coefficient of friction, such as polyimide. The coiled guide lumen may further include one or more pull wires extending through plurality of first sections. 
     A system having a centered lumen may include: a coiled guide lumen defining a longitudinal axis, the coiled guide lumen being composed of a length of wire forming a plurality of coils about the longitudinal axis, the coiled guide lumen including one or more first sections having a first diameter and one or more sections having a second diameter, the second diameter being greater than the first diameter; an elongate body including a proximal portion and a distal portion, the coiled guide lumen being within the elongate body and extending between the proximal portion and the distal portion; and a secondary guide lumen extending through the one or more first sections. The system may further include one or more pull wires extending through the secondary guide lumen. The system may further include a band coupled to an interior of the distal portion of the elongate body, and the proximal portion of the elongate body may be coupled to a handle. Each of the one or more pull wires may have a proximal portion and a distal portion, the proximal portion of the one or more pull wires being in mechanical communication with the handle and the distal portion of each of the one or more pull wires being coupled to the band. Alternatively, the system may further include a shim coupled to the band and the distal portion of each of the one or more pull wires may be coupled to the shim. 
     A system having a centered lumen may include: a coiled guide lumen defining a longitudinal axis, the coiled guide lumen being composed of a length of wire forming a plurality of coils about the longitudinal axis, the coiled guide lumen including one or more first sections having a first diameter and one or more sections having a second diameter, the second diameter being greater than the first diameter; an elongate body including a proximal portion and a distal portion, the coiled guide lumen being within the elongate body and extending between the proximal portion and the distal portion; a secondary guide lumen extending through the one or more first sections; and at least one pull wire extending through the secondary guide lumen and being attached at the distal portion of the elongate body. The system may further include an annular band coupled to an interior of the distal portion of the elongate body, and each of the at least one pull wire may be coupled to the annular band. Alternatively, the system may further include a flexible shim coupled to the annular band, and each of the at least one pull wire may be coupled to the flexible shim. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A more complete understanding of the present invention, and the attendant advantages and features thereof, will be more readily understood by reference to the following detailed description when considered in conjunction with the accompanying drawings wherein: 
         FIG. 1  shows an exemplary medical system that includes a treatment catheter including a coiled guide; 
         FIG. 2A  shows a perspective view of a first embodiment of a coiled guide, the coiled guide being formed from a flat wire; 
         FIG. 2B  shows a perspective view of the first embodiment of the coiled guide, the coiled guide being formed from a round wire; 
         FIG. 3A  shows a side view of a section of the first embodiment of the coiled guide, the coiled guide being formed from a flat wire; 
         FIG. 3B  shows a side view of the first embodiment of the coiled guide, the coiled guide being formed from a round wire; 
         FIG. 4A  shows a close-up end view of the first embodiment of the coiled guide, the coiled guide being formed from a flat wire; 
         FIG. 4B  shows a close-up end view of the first embodiment of the coiled guide, the coiled guide being formed from a round wire; 
         FIG. 5  shows a side view of the first embodiment of a coiled guide within a catheter body; 
         FIG. 6  shows a perspective view of a second embodiment of a coiled guide; 
         FIG. 7  shows a side view of the second embodiment of a coiled guide within a catheter body; 
         FIGS. 8A and 8B  show a first and second view of an attachment between a shim and a threaded element; 
         FIG. 9  shows a cross-sectional view of a coiled guide and a first embodiment of a single-deflection steering mechanism within a catheter body; 
         FIG. 10  shows a cross-sectional view of a coiled guide and a second embodiment of a single-deflection steering mechanism within a catheter body; 
         FIG. 11  shows a cross-sectional view of a coiled guide and a first embodiment of a dual-deflection steering mechanism within a catheter body; 
         FIG. 12  shows a cross-sectional view of a coiled guide and a second embodiment of a dual-deflection steering mechanism within a catheter body 
         FIG. 13  shows a cross-sectional view of a coiled guide and a second embodiment of a dual-deflection steering mechanism within a catheter body, with a secondary medical device extending through the coiled guide. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the drawing figures in which like reference designations refer to like elements, an exemplary medical system that includes a treatment catheter including a coiled guide is shown in  FIG. 1  and is generally designated as “ 10 .” The system  10  generally includes a catheter  12  that may be coupled to a control unit  14  or operating console. The catheter  12  may be configured to interact with tissue, such as with one or more electrodes  16 . For example, the catheter  12  may be a treatment catheter that is configured thermally treat tissue. The catheter  12  may also include a coiled guide  20  (which may also be referred to as a “coiled guide lumen  20 ”) extending within and along the length of the catheter, as shown and described in more detail in  FIGS. 2-13 . 
     The catheter  12  may include an elongate body  22  having a distal portion  24  and a proximal portion  26 , and defining a lumen  28  therebetween. The proximal portion  26  of the elongate body  22  may be coupled to or otherwise in mechanical, electrical, and/or fluid communication with a handle  30 , which may be, in turn, coupled to or otherwise in mechanical, electrical, and/or fluid communication with the control unit  14 . The control unit  14  may include one or more energy sources (such as radiofrequency or laser) and/or cryogenic fluid for cryotreatment, vacuums, fluid reservoirs, computers, user input devices, displays, and processors. The handle  30  may include one or more steering controls  32  that are in mechanical communication with the distal portion  24  of catheter  12 . The one or more steering controls  32  may be used, for example, to navigate the catheter  12  through the patient&#39;s vasculature and/or to modify the size, configuration, and/or operation of a treatment element or assembly at the distal portion  24 . 
     The coiled guide  20  may define a longitudinal axis  38  and may be located within the elongate body lumen  28  and may extend from the proximal portion  26  to the distal portion  24  of the elongate body  22 . The coiled guide  20  may be affixed to an inner surface of the elongate body  22 , for example, by adhesive or chemical or thermal bonding. Alternatively, the coiled guide  20  may not be affixed within the elongate body  22 . In this configuration, the catheter  12  may include a stopper at the proximal end of the elongate body  22  (not shown). In use, the coiled guide  20  may provide one or more channels or lumens along the length of the elongate body  22  for device components, such as pull wires  40 , electrical wires  42 , secondary medical devices  44  (such as a mapping catheter, as shown in  FIG. 13 ), or the like. The distal end of the elongate body  22  may include an opening  48  through which a secondary medical device  44  or other component may exit the elongate body  22 . For example, a mapping catheter  44  may extend out of the elongate body  22  and toward a target mapping or treatment site. 
     Referring now to  FIGS. 2A-13 , the coiled guide  20  is shown in greater detail. Referring specifically to  FIGS. 2A-5 , a first embodiment of the coiled guide  20  is shown. The coiled guide  20  may include a variable outer diameter, with one or more sections  50  having a first outer diameter OD 1  and one or more sections  52  having a second outer diameter OD 2 , with the second outer diameter OD 2  being greater than the first outer diameter OD 1 . Further, there optionally may be a transition section  54  on either side of the larger-diameter sections  52  that each includes a decreasing outer diameter (that is, an outer diameter that transitions from the second outer diameter OD 2  to the first outer diameter OD 1 ). The transition section  54  may include as few as one coil, in which case the diameter of the transition section coil may be greater than the first outer diameter OD 1  but less than the second outer diameter OD 2 ). Each of the smaller-diameter sections  50  may include several coils or may include as few as one coil, with each coil being a wrap of wire  56  about 360° (±15°) of the longitudinal axis  38 . As a non-limiting example, each of the smaller-diameter sections  50  may include between one and five coils, inclusive, whereas each of the larger-diameter sections  52  may include five or more coils. Each end  58  of the coiled guide  20  may include at least one terminal coil  60  that has an outer diameter that is the same or approximately the same as the first outer diameter OD 1 . Although referred to as a “wire,” the coiled guide  20  may be formed from any deformable material that can be coiled about a longitudinal axis and maintain its shape. For example, the coiled guide  20  may be made from an elongate flat strip of metal. Further, to enhance flexibility, the wire  56  may be wound such that there is a small gap between adjacent coils. The width of the gap may be chosen based on the device in which the coiled guide  20  is used and/or the procedure in which the device is used. 
     Optionally, a secondary guide lumen  66  may be inserted through the coiled guide  20 , as shown in  FIGS. 3A and 3B . For simplicity, a single unit of coiled guide  20  is shown (that is, one length of a larger-diameter portion  52 , with a transition coil  54  and a smaller-diameter coil  50  on either side). The secondary guide lumen  66  may be an elongate tube that is made of a biocompatible and has a low coefficient of friction (for example, μ≤0.5), such as polyimide. Additionally, the secondary guide lumen  66  may be sized to be passed through the coils of the smaller-diameter sections  50 . As a non-limiting example, one or more pull wires  40  (as shown in  FIGS. 5 and 7 ) and/or a secondary medical device  44  (as shown in  FIG. 13 ) may be passed through the secondary guide lumen  66 . The coiled guide  20  is configured such that the secondary guide lumen  66  and/or any other components passed through the smaller-diameter sections  50  may be centered within the elongate body  22 . This may facilitate accurate steering using the one or more pull wires  40  and/or precise placement of a secondary medical device  44  at the treatment site. Further, the low-friction material of the secondary guide lumen  66  may allow the internal components and/or a secondary medical device  44  to slide freely within the secondary guide lumen  66 . The Still further, other device components may be passed through the larger-diameter sections  52 , such as electrical wires  42  and/or fluid lumens (not shown). Thus, the larger-diameter sections  52  may also provide lumen functionality, similar to the smaller-diameter sections  50 . However, the device components passed through the larger-diameter sections  52  may not be centered within the elongate body  22 . 
     The variable diameter of the coiled guide  20  can be seen, for example, in  FIGS. 4A and 4B . The outer diameters OD 1 , OD 2  may be any diameters that are suitable for the device in which the coiled guide  20  is used and/or for the internal components of the device and the way in which the device is steered and operated. 
     The coiled guide  20  shown in  FIGS. 2A, 3A, and 4A  may be made from a flat wire  56 , whereas the coiled guide  20  shown in  FIGS. 2B, 3B, and 4B  may be made from a round wire  56 A. Otherwise, the coiled guide  20  shown in  FIGS. 2B, 3B, and 4B  may include the same features as the coiled guide  20  shown in  FIGS. 2A, 3A, and 4A . 
     Referring now to  FIGS. 6 and 7 , a second embodiment of the coiled guide  20  is shown. The coiled guide  20  of  FIG. 6  may have the same functionality as the first embodiment of the coiled guide  20  shown in  FIGS. 2A-5 . However, each of the smaller-diameter sections  50  may have a length L 1  that is greater than the length L 2  of each of the larger-diameter sections  52 . In contrast, the first embodiment of the coiled guide  20  may include smaller diameter sections  50  that each has a length L 1  that is less than the length L 2  of each of the larger-diameter sections  52 . The larger-diameter sections  52  and the transition sections  54  may each include as few as one coil, whereas the smaller-diameter sections  50  may each include a plurality of coils. As a non-limiting example, each of the larger-diameter sections  52  may include between one and five coils, inclusive, whereas each of the smaller-diameter sections  50  may include five or more coils. The embodiment shown in  FIG. 6  may be desirable when it is important that a high degree of flexibility be maintained in the elongate body  22 . Like the first coiled guide  20  embodiment shown in  FIGS. 2A-5 , the second coiled guide  20  embodiment shown in  FIG. 5  may alternatively be formed from a flat wire  56  or a round wire  56 A. Further, as shown in  FIG. 7 , a secondary guide lumen  66  and/or other device components may be passed through the coiled guide  20  as shown and described in  FIGS. 2A-5 . 
     Referring now to  FIGS. 8A-12 , non-limiting embodiments of a steering mechanism are shown.  FIGS. 8A and 8B  show a means of attachment between a threaded assembly  70  in the distal portion  24  of the elongate body  22  to which a shim  72  may be coupled. For example, the threaded element  70  may be, may define, or may include a threaded annular band. The threaded element  70  is shown in  FIGS. 8A and 8B  as an assembly having a proximal portion  70 A and a distal portion  70 B. The proximal portion  70 A may be hollow and may include threading  74  on an inner surface, and the distal portion  70 B may be hollow or at least partially hollow and at least a portion of the inner surface may also include threading  74 . That is, the threading  74  may extend entirely or partially within the distal portion  70 B. The threaded element  70  is shown in  FIGS. 9-12  as an annular band. The threaded element  70  may be coupled to the interior of the elongate body  22  so that it does not move within the elongate body  22  when a pull force is exerted on the pull wire  40 . Further, the threaded element  70  may be composed of rigid material, such as metal or plastic. The shim  72  may be a flattened plate that includes threading  76  on two of its edges, the threading  76  being rotatably matable with (that is, able to be screwed into) the threading  74  within the threaded element  70 . Further, the shim  72  may be dimensioned such that the shim  72  is securely attached within the threaded element  70  when the shim  72  is screwed in. The shim  72  may be composed of a flexible and resilient material, such as thin layer of metal or plastic. 
       FIGS. 9 and 10  each show a steering method embodiment in which the distal portion  24  of the elongate body  22  may be deflected in a single direction, and  FIGS. 11 and 12  each show a steering method embodiment in which the distal portion  24  of the elongate body  22  may be deflected in two directions. The pull wire  40  may be attached to, such as welded or bonded to, a surface of the shim  72  so that a pull force exerted on the pull wire  40  may cause the shim  72 , and therefore the distal portion  24  of the elongate body  22 , to deflect toward the side of the shim to which the pull wire  40  is attached. Thus, the elongate body  22  may be deflectable in a single direction. The shim  72  may have an at least substantially continuous width, as shown in  FIGS. 8A and 8B , or it may be tapered as shown in  FIGS. 9 and 11 , with the distal end being wide enough to be screwed into the threaded element  70 . The narrower diameter of the proximal portion of the shim  72  may enhance flexibility of the shim  72 . 
     In the alternative embodiment shown in  FIG. 10 , the pull wire  40  may be attached directly to the band  70 , but may produce the same one-directional deflection as the embodiment shown in  FIG. 9 . 
     The embodiment shown in  FIG. 11  is similar to the embodiment shown in  FIG. 9 , except the catheter  12  may include two pull wires  40 ,  40 A attached to the shim  72 . For example, one pull wire  40  may be attached to one face of the shim  72  and a second pull wire  40 A may be attached to the opposite face of the shim  72 . A pull force exerted on the pull wire  40  may cause the shim  72 , and therefore the distal portion  24  of the elongate body  22 , to deflect toward the side of the shim  72  to which the pull wire  40  is attached. Similarly, a pull force exerted on the pull wire  40 A may cause the shim  72 , and therefore the distal portion  24  of the elongate body  22 , to deflect toward the side of the shim  72  to which the pull wire  40 A is attached. Thus, the elongate body  22  may be deflectable in two directions. 
     In the alternative embodiment shown in  FIG. 12 , the pull wires  40 ,  40 A may be attached directly to the band  70 , but may produce the same dual-directional deflection as the embodiment shown in  FIG. 11 . 
     When the coiled guide  20  is used in a catheter, the elongate body  22  of the catheter may be manufactured in a simple, efficient, and cost-effective process. For example, instead of complicated extrusion, a plurality of elongate bodies  22  may be manufactured in a single, continuous extruded tube having a single lumen. The continuous extruded tube may then be cut into a plurality of working lengths, each length becoming a catheter elongate body. After extrusion, one or more coiled guides  20  may be inserted into an elongate body to provide the elongate body with one or more lumens through which various device components and/or secondary medical devices may be passed. 
     It will be appreciated by persons skilled in the art that the present invention is not limited to what has been particularly shown and described herein above. In addition, unless mention was made above to the contrary, it should be noted that all of the accompanying drawings are not to scale. A variety of modifications and variations are possible in light of the above teachings without departing from the scope and spirit of the invention, which is limited only by the following claims.