Patent Publication Number: US-2010130852-A1

Title: Navigation enabled lead delivery catheter

Description:
FIELD 
     The present disclosure relates generally to catheter systems and, more specifically, relates to a navigation enabled lead delivery catheter. 
     BACKGROUND 
     The statements in this section merely provide background information related to the present disclosure and may not constitute prior art. 
     Various devices have been proposed for introducing and/or positioning elongate medical instruments in the human body. For instance, various catheter systems, introducer sheaths, and other elongate tubular members have been proposed for these purposes. More specifically, these devices can include a proximal portion that remains outside the body and a tubular member that extends into the body such that a distal end of the tubular member is located at a desired position. A medical instrument, such as a cardiac pacemaker lead or other vascular instrument, passes longitudinally through a lumen of the tubular member toward the desired position. For instance, in some embodiments, the medical instrument extends through the lumen to be positioned within the patient&#39;s heart, blood vessel, or other portion of the body. Then, the medical professional removes the tubular member of the catheter system, leaving the medical instrument in its intended position within the body. For example, the catheter system can be cut or peeled longitudinally as it is pulled from the body, thereby allowing the medical instrument to move outside the lumen of the catheter system, and leaving the distal end of the medical instrument in its intended position within the body. 
     Although conventional catheter systems have functioned for the intended purposes, some problems remain. For instance, it can be difficult to properly locate and position the distal end of the catheter system into the desired position within the body. As such, the medical instrument may be extended through the lumen of the catheter system into an incorrect position within the body, and the medical instrument may malfunction and/or need to be repositioned. 
     For instance, medical professionals typically manipulate the proximal end of the catheter system by pushing, pulling, and twisting the proximal end, and these forces are transferred longitudinally along the catheter system to thread the distal end into the desired position within the body. However, some catheter systems may not provide sufficient structural rigidity to properly transfer the forces from the proximal end to the distal end, thereby hindering the intended movement of the distal end. 
     Moreover, because the distal end is within the body, and the medical professional cannot view the distal end directly, it can be difficult to position the distal end with a high degree of accuracy. In some cases, navigation tools are used to more accurately locate the distal end. More specifically, these tools can include a coil of wire that is wound around the outside of the distal end. Then, a current is induced within the coil by generating an electromagnetic field from outside the patient. This induced current is detected in order to triangulate and locate the distal end within the body. However, in cases where the catheter system is split longitudinally after the medical instrument is placed, the coil may need to be segmented and the patient&#39;s exposure to the material of the coil should be limited, which can be problematic. 
     SUMMARY 
     This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features. 
     A catheter system for positioning of a medical instrument is disclosed. The catheter system includes a first elongate member having a first lumen. The catheter system also includes a second elongate member that includes a second lumen that receives the medical instrument. The second elongate member is coupled directly to the first elongate member, and the second elongate member is operable to be at least partially segmented generally along a second longitudinal axis thereof to allow movement of the medical instrument outside the second lumen. The second elongate member is selectively collapsible and expandable to change a size of the second lumen. 
     A method of positioning a medical instrument is also disclosed. The method includes positioning a catheter system in a patient. The catheter system includes a first elongate member that includes a first lumen and a second elongate member that includes a second lumen. The second elongate member is coupled directly to the first elongate member. The method also includes expanding the second elongate member to increase a size of the second lumen and extending the medical instrument into the second lumen. Moreover, the method includes segmenting the second elongate member to move the medical instrument outside the second lumen. 
     In still another aspect, a catheter system for positioning of a medical instrument is disclosed. The catheter system includes a first elongate member that includes a first lumen and an outer surface. The catheter system also includes a reinforcing member that reinforces the first elongate member. Furthermore, the catheter system includes a navigation tool with an electrically conductive coil operable for detecting a location of the catheter system. The navigation tool is received in the first lumen. Moreover, the catheter system includes a second elongate member that includes a second lumen that receives the medical instrument and an outer surface. The outer surface of the second elongate member is longitudinally coupled directly to the outer surface of the first elongate member. The second elongate member is operable to be at least partially segmented generally along a second longitudinal axis thereof to allow movement of the medical instrument outside the second lumen. The second elongate member is selectively collapsible and expandable to change a size of the second lumen. Furthermore, the catheter system includes a port member having a first port in fluid communication with the first lumen and a second port in fluid communication with the second lumen. The navigation tool extends through the first port and into the first lumen, and the medical instrument is extendable through the second port and into the second lumen. 
     Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. 
    
    
     
       DRAWINGS 
       The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way. 
         FIG. 1A  is a perspective view of a catheter system according to various teachings of the present disclosure illustrated with a first elongate member and a second elongate member that is in a collapsed state; 
         FIG. 1B  is a perspective view of the catheter system of  FIG. 1A  with the second elongate member illustrated in an inflated state; 
         FIG. 2  is a perspective view of a port member of the catheter system of  FIGS. 1A and 1B ; 
         FIG. 3  is a perspective view of the catheter system of  FIG. 1B  with a navigation tool and a medical instrument extending therethrough; 
         FIG. 4  is a perspective view of the catheter system of  FIG. 1B  shown during a cutting operation; 
         FIG. 5  is a sectional view of the catheter system of  FIG. 1A  shown during a manufacturing operation thereof; 
         FIG. 6  is a sectional view of the catheter system taken along the line  6 - 6  of  FIG. 1B ; and 
         FIG. 7  is a sectional view of the catheter system taken along the line  7 - 7  of  FIG. 1B . 
     
    
    
     DETAILED DESCRIPTION 
     The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features. 
     Referring initially to  FIGS. 1A ,  1 B,  6  and  7 , a catheter system  10  according to various exemplary embodiments is illustrated. The catheter system  10  can include a first elongate member  12  and a second elongate member  14 . The second elongate member  14  can be collapsible and expandable. More specifically,  FIG. 1A  illustrates one exemplary embodiment of the second elongate member  14  in a collapsed state, and  FIG. 1B  illustrates one exemplary embodiment of the second elongate member  14  in an expanded state. As will be discussed in greater detail below, the collapsibility and expandability of the second elongate member  14  can facilitate use of the catheter system  10  for added convenience. 
     The first elongate member  12  can be tubular, hollow, and generally flexible. As such, the first elongate member  12  can include a first lumen  16  ( FIG. 6 ). Also, the first elongate member  12  can include a first longitudinal axis X 1 . Moreover, the first elongate member  12  can include a proximal end  18 , a distal end  20 , and an outer surface  21 . 
     Moreover, in some embodiments, the first elongate member  12  can include a reinforcing member  22 . The reinforcing member  22  can generally reinforce the first elongate member  12 . Accordingly, in some embodiments, the reinforcing member  22  can be embedded the first elongate member  12 . More specifically, in some exemplary embodiments, the reinforcing member  22  can be helical and wind about the first axis X 1  in a helical manner. In other embodiments, the reinforcing member  22  is a braided member such that the reinforcing member  22  includes a plurality of helical members that helically wind about the first axis X 1  and that intersect each other along the axis X 1 . 
     The reinforcing member  22  can be made of any suitable material, such as metal. The other tubular portion of the first elongate member  12  can be made out of any suitable material, such as a polymer. In some exemplary embodiments, the first elongate member  12  can be made from a braided shaft or a spiral cut hypotube, commercially available from  . 
     It will be appreciated that the reinforcing member  22  reinforces the first elongate member  12  to increase the rigidity of the first elongate member  12  such that forces applied at the proximal end  18  (e.g., forces exerted along the axis X 1  and/or rotational forces exerted about the axis X 1 ) can be transferred to the distal end  20  due to the reinforcement supplied by the reinforcing member  22 . Accordingly, the first elongate member  12  can be more easily manipulated, routed along a non-linear path (e.g., a blood vessel), and the like. 
     Furthermore, in some embodiments, the second elongate member  14  is tubular and hollow so as to define a second lumen  24  ( FIG. 7 ) extending along a second longitudinal axis X 2 . Furthermore, the second elongate member  14  includes a proximal end  26  and a distal end  28 . Additionally, the second elongate member  14  includes an inner surface  29  and an outer surface  30 . 
     The second elongate member  14  can be made of any suitable material, such as a polymeric material. In some embodiments, the second elongate member  14  can be made of a material similar to that of a known percutaneous transluminal coronary angioplasty (PTCA) balloon. 
     As is best illustrated in  FIGS. 1  B and  7 , the second elongate member  14  can be longitudinally coupled directly to the first elongate member  12 . More specifically, the outer surface  30  of the second elongate member  14  can be fixed to the outer surface  21  of the first elongate member  12  such that the second axis X 2  extends substantially in the same direction as the first longitudinal axis X 1 . It will be appreciated that the first and second elongate members  12 , 14  could be coupled in any suitable manner. For instance, in some exemplary embodiments, the first and second elongate members  12 ,  14  can be fixed together with an adhesive  31  that extends along the axis X 1 , X 2 . In other exemplary embodiments, the first and second elongate members  12 ,  14  can be over-molded together. 
     The second elongate member  14  can be configured to be selectively collapsible and expandable to change the size of the second lumen  24  within the second elongate member  14 . More specifically, in some exemplary embodiments, the second elongate member  14  can have a thin wall thickness as compared with the first elongate member  12 . For instance, in some exemplary embodiments, the second elongate member  14  can have a wall thickness between approximately 0.0007″ and 0.0015″ while the wall thickness of the first elongate member  12  is approximately 0.01″. 
     Furthermore, as will be described in greater detail below in relation to  FIG. 4 , the second elongate member  14  can be configured to be at least partially segmented generally along the second longitudinal axis X 2 . For instance, as will be described in greater detail below, the second elongate member  14  can be cut so as to provide access into and out of the second lumen  24 . Also, as will be discussed below, because the second elongate member  14  is collapsible and expandable and segmentable, the catheter system  10  can be more convenient during use. 
     Moreover, in some exemplary embodiments, the catheter system  10  can include an end member  32  ( FIGS. 1A ,  1 B,  6 ). The end member  32  can be tubular and hollow so as to define a third lumen  34  ( FIG. 6 ). The end member  32  can be coupled to the proximal end  26  of the second elongate member  14  such that the third lumen  34  is in fluid communication with the second lumen  24  of the second elongate member  14 . Also, the end member  32  can be longitudinally coupled and fixed to the outer surface  21  of the first elongate member  12 . In some exemplary embodiments shown in  FIG. 6 , the end member  32  can include a recess  35  along the entire longitudinal length of the end member  32 , and the recess  35  receives a portion of the first elongate member  12 . It will be appreciated that the end member  32  can be coupled to the first elongate member  12  and the second elongate member  14  in any suitable fashion. For instance, in some exemplary embodiments, the end member  32  can be fixed to the elongate members  12 ,  14  via an adhesive. In other exemplary embodiments, the end member  32  can be over-molded to the first elongate member  12  and/or the second elongate member  14 . 
     The end member  32  can be made of a material more resistant to deformation (i.e., more rigid) than that of the second elongate member  14 . More specifically, the end member  32  can be configured such that the third lumen  34  retains substantially the same shape regardless of whether the second elongate member  14  is collapsed or expanded. Also, in some exemplary embodiments, the end member  32  can be made of a polymeric material and has a wall thickness of approximately 0.004″. 
     Furthermore, in the exemplary embodiments shown in  FIGS. 1A ,  1 B, and  2 ), the catheter system  10  can include a port member  36 . Generally, the port member  36  includes a main body  39 , a first branch  41 , and a second branch  43  disposed between the main body  39  and the first branch  41 . Also, in some exemplary embodiments, the port member  36  includes a first port  40 , which extends through the first branch  41  and is in fluid communication with a common aperture  38 . Additionally, the port member  36  includes a second port  42 , which extends through the main body  39  and is in fluid communication with the common aperture  38 . Moreover, the end member  36  can include a third port  44 , which extends through the second branch  43  and is in fluid communication with the second port  42 . 
     The port member  36  can be made out of any suitable material, such as a polymeric material. Also, the port member  36  can be generally rigid. Additionally, the port member  36  can include a thin walled portion  35  which extends longitudinally along the main body  39 . As will be discussed in greater detail below, the thin walled portion  45  can be segmented (e.g., cut). The port member  36  can also include one or more coupling members, such as luer locks or other couplings disposed adjacent respective ends of the first branch  41 , the second branch  43 , and the main body  39 . 
     The port member  36  can also be operatively coupled to the first and second elongate members  12 ,  14  as well as the end member  32 . For instance, in some exemplary embodiments, the end member  32  is received within the common aperture  38 , and the end member  32  extends into the main body  39  ( FIGS. 1A and 1B ). In some exemplary embodiments, the second and third ports  42 ,  44  are in fluid communication with the third lumen  34  of the end member  32  and, thus, the second lumen  24  of the second elongate member  14 . Moreover, the proximal end  18  of the first elongate member  12  can be received within the common aperture  38  and into the first port  40  such that the first port  40  is in fluid communication with the first lumen  16  of the first elongate member  12 . 
     It will be appreciated that the port member  36  can be coupled to the end member  32 , the first elongate member  12 , and the second elongate member  14  in any suitable fashion. For instances, in some exemplary embodiments, an adhesive is used for these purposes. In other exemplary embodiments, the port member  36  is over-molded to the end member  32  and/or the first elongate member  12 . 
     It will also be appreciated that the end member  32  is optionally included in the catheter system  10 . For instance, in some exemplary embodiments, the second elongate member  14  can be coupled directly to the port member  36  such that the second elongate member  14  is received within the common aperture  38  and such that the second and third ports  42 ,  44  are in fluid communication with the second lumen  24  of the second elongate member  14 . Moreover, it will be appreciated that the third port  44  and the second branch  43  are optional. For instance, in some exemplary embodiments, the port member  36  includes only the main body  39  and the first branch  41 . 
     Accordingly, operation of the catheter system  10  will be described in greater detail. As shown in  FIG. 3 , the first and second elongate members  12 ,  14  are inserted into a patient (shown schematically at  46 ) through a prepared incision  48 . In some exemplary embodiments, the second elongate member  14  is collapsed as shown in  FIG. 1A  as the catheter system  10  is inserted through the incision  48 . Also, in some exemplary embodiments, the outer surface  21 ,  30  of the first and second elongate members  12 ,  14  are at least partially coated with a lubricant to reduce friction as the first and second elongate members  12 ,  14  are inserted into the incision  48  and threaded into the patient  46 . 
     Furthermore, in some exemplary embodiments, the location of the distal end  20  of the first elongate member  12  is detected to ensure that the distal end  20  is in a predetermined position within the patient  46 . In some embodiments, placement and location of the distal end  20  within the patient  46  is performed using a navigation tool  52 . It will be appreciated that the navigation tool  52  could be used to detect the position of any suitable portion of the catheter system  10 . 
     In some exemplary embodiments, the navigation tool  52  can be elongate and includes an electrically conductive coil  54  on one end thereof. The navigation tool  52  can be of any suitable type, such as the navigation tool  52  disclosed in Applicant&#39;s co-pending U.S. patent application Ser. No. ______, filed ______, which is incorporated herein by reference in its entirety. Thus, the navigation tool  52  can be used in conjunction with a locating device  53 . The locating device  53  can include microprocessors, computer memory, and other computer components for calculating and detecting the position of the coil  54 , and thus, the position of the navigation tool  52  within the patient  46 . Also, the locating device  53  can be used in combination with Johnson &amp; Johnson&#39;s CARTO XP EP Navigation and Ablation System, commercially available from Johnson &amp; Johnson of New Brunswick, N.J. Furthermore, the locating device  53  can be used in combination with the FLUOROMERGE or AXIEM Electromagnetic Tracking Systems, commercially available from Medtronic Surgical Navigation Technologies, Inc. of Minneapolis, Minn. 
     Accordingly, the locating device  53  can generate a variable electromagnetic field about the patient  46 , and the electromagnetic field can induce a current within the coil  54  of the navigation tool  52 . The induced current is dependent upon the position of the coil  54  relative to the locating device and within the electromagnetic field. Accordingly, the locating device  53  can triangulate the coil  54  to, thereby, detect the position of the navigation tool  52  within the patient  46 . Also, the locating device  53  can rely on imaging technology (X-ray, MRI, CT, etc.) to produce visual feedback of the position of the navigation tool  52  within the patient  46 . 
     Thus, the navigation tool  52  can be inserted into the first elongate member  12  of the catheter system  10  via the second port  42  of the port member  36 . More specifically, the navigation tool  52  can be extended into the first port  40 , and into the first lumen  16 , and threaded along the first axis X 1 . It will be appreciated that the navigation tool  52  could be inserted into the first elongate member  12  either before or after the first elongate member  12  is inserted into the patient  46 . In either case, the navigation tool  52  can be used to detect the position of the distal end  20  of the first elongate member  12  and to move the distal end  20  into a predetermined position within the patient  46 . It will be appreciate that the distal end  28  of the second elongate member  14  can be disposed in a predetermined and known position relative to the distal end  20  of the first elongate member  12 , and as such, the navigation tool  52  can be used to similarly move the distal end  28  of the second elongate member  14  into a predetermined position within the patient  46 . 
     Also, in some exemplary embodiments, a working fluid  51  is then introduced into the second lumen  24  via the third port  44  of the port member  36 . The working fluid  51  flows into the second lumen  24  and applies fluid pressure against the inner surface  29  of the second lumen  24  to expand the second elongate member  14  from a collapsed state ( FIG. 1A ) to an expanded state ( FIG. 1B ). The working fluid  51  could be of any suitable type, such as saline. 
     Once the second elongate member  14  is sufficiently expanded, the medical instrument  50  can be inserted into the second lumen  24 . More specifically, the medical instrument  50  is threaded into the second port  42  of the port member  36 , through the third lumen  34  of the end member  32 , and is received in the second lumen  24  of the second elongate member  14 . The medical instrument  50  can be threaded along the second lumen  24  until it extends out of the distal end  28  of the second elongate member  14  toward a desired location within the patient. Then, in some exemplary embodiments, the medical instrument  50  can be attached to tissue (not shown) of the patient  46  in any suitable, known fashion. 
     It will be appreciated that the medical instrument  50  could be of any suitable type. For instance, in some exemplary embodiments, the medical instrument  50  is a pacemaker lead. 
     In another embodiment, the working fluid  51  is not used to expand the second elongate member  14 , and instead, insertion of the medical instrument  50  causes expansion of the second elongate member  14 . More specifically, as the medical instrument  50  progressively extends along the axis X 2 , the medical instrument  50  pushes the inner surface  29  of the second elongate member  14  outward radially to expand the second elongate member  14 . Also, the inner surface  29  of the second lumen  24  can include a lubricant for reducing friction and facilitating movement of the medical instrument  50  along the axis X 2  of the second elongate member  14 . 
     Once the medical instrument  50  is in the desired position with the patient  46 , the catheter system  10  can be removed from the medical instrument  50 . More specifically, in some exemplary embodiments illustrated in  FIG. 4 , a blade  56  can be used to at least partially segment (e.g., cut) the port member  36 , the end member  32 , and the second elongate member  14 . In some embodiments, the port member  36  is pulled away from and out of the patient  46  to withdraw the first and second elongate members  12 ,  14 , and the blade  56  simultaneously cuts (i.e. slits) longitudinally along the thin walled portion  45  of the port member  36 , along the end member  32 , and through the wall thickness of the second elongate member  14  generally parallel to the second longitudinal axis X 2 . As such, the medical instrument  50  can be moved out of the port member  36 , the end member  32 , and the second lumen  24  of the second elongate member  14 . Accordingly, the catheter system  10  is removed from the patient  46  while the blade  56  simultaneously cuts, and the catheter system  10  can be removed from the medical instrument  50 , leaving the medical instrument  50  in its desired position within the patient  46 . 
     It will be appreciated that the port member  36 , the end member  32 , and/or the elongate member  14  can be segmented in any suitable fashion. For instance, in other exemplary embodiments, the second elongate member  14  is scored generally along the second axis X 2 , such that the second elongate member  14  can be peeled along the axis X 2  along the scoring without the use of the blade  56 . 
     It will also be appreciated that the catheter system  10  can be segmented in any direction other than along the second axis X 2 . Moreover, it will be appreciated that the catheter system  10  can be only partially segmented along the axis X 2  in order to remove the catheter system  10  from the medical instrument  50 . 
     Accordingly, the catheter system  10  allows the medical instrument  50  to be accurately positioned within the patient  46  such that the medical instrument  50  is more likely to operate in an intended fashion. Also, because the medical instrument  50  is isolated from the navigation tool  52 , the medical instrument  50  can be easily removed from the catheter system  10  simply by cutting through the relatively thin wall of the second elongate member  14 . Furthermore, because exposure to the material of the coil  54  of the navigation tool  52  is unlikely because it is not segmented during removal of the catheter system  10 . 
     Manufacturing of the catheter system  10  will now be described with reference to  FIG. 5 . In the exemplary embodiment represented in  FIG. 5 , the catheter system  10  is manufactured by first fixing the first elongate member  12  to the second elongate member  14 . As discussed above, the first and second elongate members  12 ,  14  can be secured using an adhesive  31 . Then, the second elongate member  14  is collapsed so as to reduce the size of the second lumen  24 . In some embodiments, the second elongate member  14  is folded, pleated, or otherwise collapsed onto the outer surface  21  of the first elongate member  12 . Next, the first and second elongate members  12 ,  14  are positioned within a removable sleeve  60  that encompasses the first and second elongate members  12 ,  24 . In some exemplary embodiments, the removable sleeve  60  biases and retains the second elongate member  14  in its collapsed position. Subsequently, heat is applied to the assembly in a known heat treating process, such that the second elongate member  14  substantially retains its shape in the collapsed position. Accordingly, the heating of the second elongate member  14  can set the second elongate member  14  in the collapsed position. In some exemplary embodiments, the sleeve  60  remains on the first and second elongate members  12 ,  14  until the catheter system  10  is ready to be inserted into the patient  46  and is removed thereafter. Accordingly, the sleeve  60  can act as a packaging for the catheter system  10 . In other exemplary embodiments, the sleeve  60  can be a temporary sleeve  60  that is only used during the heating step represented in the exemplary embodiment of  FIG. 5 . Thus, the sleeve  60  is removed after heating, and the first and second elongate members  12 ,  14  are placed in a different sleeve  60  for packaging purposes. In either case, the sleeve  60  is removed before the catheter system  10  is inserted into the patient  46 . 
     Certain terminology is used herein for purposes of reference only, and thus is not intended to be limiting. For example, terms such as “upper,” “lower,” “above,” “below,” “top,” “upward,” and “downward” refer to directions in the drawings to which reference is made. Terms such as “front,” “back,” “rear,” and “side,” describe the orientation of portions of the component within a consistent but arbitrary frame of reference which is made clear by reference to the text and the associated drawings describing the component under discussion. Such terminology may include the words specifically mentioned above, derivatives thereof, and words of similar import. Similarly, the terms “first,” “second,” and other such numerical terms referring to structures do not imply a sequence or order unless clearly indicated by the context. 
     When introducing elements or features and the exemplary embodiments, the articles “a,” “an,” “the” and “said” are intended to mean that there are one or more of such elements or features. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements or features other than those specifically noted. It is further to be understood that the method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed. 
     The description of the disclosure is merely exemplary in nature and, thus, variations that do not depart from the gist of the disclosure are intended to be within the scope of the disclosure. Such variations are not to be regarded as a departure from the spirit and scope of the disclosure.