Abstract:
A steerable delivery device comprising an outer sheath and an inner sheath disposed within the outer sheath, wherein the outer sheath includes a first tubular element, a steerable portion adapted to be steered, and wherein in a cross section along the steerable portion the first tubular element includes a first section of a first material with a first durometer and a second section of a second material with a second durometer different than the first durometer.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]    This application claims the benefit of U.S. Provisional App. No. 61/699,783, filed Sep. 11, 2012; and is related to and incorporates by reference herein the following applications: U.S. application Ser. No. 12/823,049, filed Jun. 24, 2010, U.S. application Ser. No. 13/463,537, filed May 3, 2012, and U.S. application Ser. No. 13/463,498, filed May 3, 2012, U.S. Prov. App. No. 61/220,160, filed Jun. 24, 2009, U.S. Prov. App. No. 61/220,163, filed Jun. 24, 2009, U.S. Prov. App. No. 61/232,362, filed Aug. 7, 2009, U.S. Prov. App. No. 61/482,018, filed May 3, 2011, U.S. Prov. App. No. 61/555,687 filed Nov. 4, 2011, U.S. Prov. App. No. 61/555,706, filed Nov. 4, 2011. 
     
    
     INCORPORATION BY REFERENCE  
       [0002]    All publications and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0003]      FIGS. 1A-1C  illustrate exemplary inner tubular member  100 .  FIG. 1A  is a top view.  FIG. 1B  is a view rotated 90 degrees relative to the  FIG. 1A  view, and  FIG. 1C  is a view rotated 180 degrees relative to the view in  FIG. 1A  (and 90 degrees relative to the view in  FIG. 1B ). 
           [0004]      FIGS. 2A-2C  illustrate exemplary outer tubular  200  that is part of the delivery device and is disposed outside of and around inner tubular member  100 .  FIG. 2A  is a top view.  FIG. 2B  is a view rotated 90 degrees from the view in  FIG. 2A , and  FIG. 2C  is a view rotated 180 degrees from the view in  FIG. 2A  (and 90 degrees from the view in  FIG. 2B ). 
           [0005]      FIGS. 3A-3E  illustrate views of assembly  300  including the inner and outer tubular members  100  and  200 , respectively, from  FIGS. 1 and 2 . 
       
    
    
     DETAILED DESCRIPTION  
       [0006]    The disclosure herein relates generally to steerable delivery devices, and is related to the disclosure of U.S. application Ser. No. 13/463,498, filed May 3, 2012. The exemplary delivery devices described herein are similar to those shown in FIGS. 53A-G in U.S. application Ser. No. 13/463,498. In particular, the inner tubular member of the delivery devices herein is similar to inner tubular member 1652 described in reference to FIGS. 35A-G in U.S. application Ser. No. 13/463,498. The exemplary embodiment in FIGS. 35A-G is described generally in paragraph [00178] in U.S. application Ser. No. 13/463,498. 
         [0007]      FIGS. 1A-1C  illustrate exemplary inner tubular member  100 .  FIG. 1A  is a top view.  FIG. 1B  is a view rotated 90 degrees relative to the  FIG. 1A  view, and  FIG. 1C  is a view rotated 180 degrees relative to the view in  FIG. 1A  (and 90 degrees relative to the view in  FIG. 1B ). 
         [0008]    Inner tubular member  100  includes steerable distal section  114  and a proximal section  102 . Proximal section  102  includes a proximal tubular element  116  with a first durometer. In the embodiment shown proximal tubular element  116  has a durometer of 72D and is a Pebax/vestamid material. Steerable distal section  114  includes tubular element  104  and spine  106 . Spine  106  is similar to first portion 1658 from FIGS. 35A-G in U.S. application Ser. No. 13/463,498. Tubular element  104  has a lower durometer than proximal tubular element  116 . In this embodiment tubular element  104  has a durometer of 35D, and is Pebax. Spine  106  has optional proximal and distal cuff portions that extend all the way around the device, and a spine section that extends between the two cuff portions that does not extend all the way around the device. In the spine section spine  106  makes up about ¼ of inner tubular member  100 , and tubular element  104  makes up about ¾ of the inner tubular member  100 . Inner tubular member  100  also includes tensioning member  108  that is secured to the distal end  110  of cuff portion and to the distal end  112  of proximal section  102 . Tensioning member  108  is free floating in between the two points at which it is secured. Tensioning member  108  is directly adjacent to, and in alignment with, the spine section of spine  106  (as can be seen in  FIG. 1C ). In this embodiment tensioning member  108  is a Kevlar line. Spine  106  has a greater durometer than tubular element  104 , and in this embodiment is 72D Pebax. 
         [0009]    As is described in more detail in U.S. application Ser. No. 13/463,498, the lower durometer of tubular element  104  relative to proximal tubular element  116  allows the steerable distal section to bend. Spine  106 , however, due to its higher durometer, reduces shortening in compression and stretching in tension, as can occur in the distal section when it is actuated. For example, the distal section of the inner tubular member may sometimes compress, or shorten, when it is pushed in relative to the outer tubular member to straighten the steerable portion from a bent configuration towards a straighter configuration. The durometers provided are not intended to be limiting but merely illustrative. 
         [0010]      FIGS. 2A-2C  illustrate exemplary outer tubular  200  that is part of the delivery device and is disposed outside of and around inner tubular member  100 .  FIG. 2A  is a top view.  FIG. 2B  is a view rotated 90 degrees from the view in  FIG. 2A , and  FIG. 2C  is a view rotated 180 degrees from the view in  FIG. 2A  (and 90 degrees from the view in  FIG. 2B ). 
         [0011]    Outer tubular member  200  includes a proximal section  202  and steerable, or articulating, distal section  214 . Proximal section  202  has a proximal tubular element  204  with a first durometer. In this embodiment proximal tubular element  204  is a 72D Pebax/Vestamid material. Distal articulating section  214  includes spine  206 , which is structurally the same as the spine in  FIGS. 1A-1C . Spine  206  includes distal and proximal cuffs and a spine section extending between the two optional cuff portions. In this embodiment spine  206  is 72D Pebax. Articulating section  214  also includes first section  208 , second section  210 , and third section  212 , all of which have different durometers. In this embodiment the durometers decrease towards the distal end of the device. In this embodiment first section  208  is 55D Pebax, second section  210  is 40D Pebax, and third section  212  is 35D Pebax. The multiple bands of different durometer materials (three in this embodiment) in the outer tubular member provide for a more uniform radius of curvature when the steerable section is bent. To the contrary, in embodiment in which the tubular element is all one durometer (excluding the spine), the radius of curvature of the steerable section is generally smallest at the most distal location and increases towards the proximal end. This radius of curvature variation essential forms a spiral in the steerable section. Proximal tubular element  204  has a greater durometer than all three sections  208 ,  210 , and  212 . The distal articulating section  214  also includes distal tip  216 . In this embodiment distal tip  216  is the lowest durometer material, and in this embodiment is 20D Pebax. 
         [0012]    The embodiments herein with the outer spine and the multiple durometer steerable sections provides for advantages in bidirectional use. For example, less force is required to bend the multiple durometer arrangement, hence there is less foreshortening or conversely less stretching when the element is used in tension. This advantage would also hold true for unidirectional steering. 
         [0013]    As is described in more detail in the assembly shown in  FIGS. 3A-3C , the spines in the inner and outer tubular members are offset 180 degrees from one another. Tensioning member  108  is therefore also offset 180 degrees from the outer spine. 
         [0014]      FIGS. 3A-3E  illustrate views of assembly  300  including the inner and outer tubular members  100  and  200 , respectively, from  FIGS. 1 and 2 . As can be seen in  FIGS. 3A and 3E , tensioning member  108  is offset 180 degrees from outer spine  206 . The inner and outer spines are also offset by 180 degrees. 
         [0015]    The assembly  300  can be used as is described in the applications incorporated by reference herein. For example, the inner and outer tubular members can be axially moved relative to one another to steer the distal steerable section. When a spine from one tubular member is put in tension, the other spine is put in compression. The dual spine embodiment reduces shortening in one tubular member in compression and stretching in the other tubular member in tension. 
         [0016]    In some embodiments the inner or outer tubular members are formed by positioning the different materials on a mandrel, placing shrink wrap over the different materials, and increasing the temperature, which causes the material to melt together, forming the inner or outer tubular members. The optional cuffs described above can be helpful in securing one or more components together during the manufacturing process. 
         [0017]    Any of the inner and outer tubular members described in U.S. application Ser. No. 13/463,498, filed May 3, 2012 that comprise one or more slots or spines can be made of an elastomeric or polymeric material. For example, in U.S. application Ser. No. 13/463,498, the tubular members shown in FIG. 2, 3, or 4 with slots and spines therein can be made from Pebax.