Dual-profile steerable catheter with shaft support system for resisting axial compressive loads

Abstract

A catheter includes a steering mechanism for manipulating the distal end of the catheter to obtain a plurality of deflection profiles, a torque transfer system to enhance torque transfer from the handle to the distal tip, and a support system to reduce undesirable deformation of the distal-end region during steering. The torque transfer system includes a flat ribbon within the relatively flexible distal-end region to enhance torque transfer through the distal-end region of the catheter. The support system includes a compression cage and longitudinal struts that are located within the distal-end region of the catheter. The support system can support axial loads and deflect laterally in the direction of the steering, thereby reducing the amount of stretching and compression of the catheter sheath within the deflecting region.

What is claimed is:  
     
         1 . A method of delivering therapeutic treatment to a biological site, comprising: 
 providing a catheter having, 
 a sheath including a proximal region, a distal-end region, and longitudinal centerline,  
 a support system having a proximal end, a distal end and a lumen there between, the support system sized to fit within the distal-end region of the sheath and configured to deflect laterally relative to the centerline and to resist axial compression along the centerline, and  
 a torque transfer system housed within the compression cage and adapted to transfer torsional forces from the proximal region of the sheath to the distal-end region of the sheath;  
   manipulating the distal end region of the catheter until the distal-end region of the catheter is proximate the biological site; and    providing therapeutic treatment to the biological site.    
     
     
         2 . The method of  claim 1 , wherein providing a catheter having a support system includes providing a catheter having a support system including a helical coil defining the lumen and at least one strut secured to one side of the coil throughout the length of the coil.  
     
     
         3 . The method of  claim 2 , wherein providing a catheter having a support system including a helical coil and at least one strut secured to one side of the coil throughout the length of the coil includes providing a catheter having a support system including a pair of struts secured to diametrically opposite sides of the coil.  
     
     
         4 . The method of  claim 2 , wherein providing a catheter having a support system including a helical coil and at least one strut secured to one side of the coil throughout the length of the coil includes providing a catheter having a support system which is formed of a resiliently deformable, shape-memory material.  
     
     
         5 . The method of  claim 1 , wherein providing a catheter having a support system includes providing a catheter having a support system including a linear array of hollow rings defining the lumen and at least one strut secured to one side of each of the rings.  
     
     
         6 . The method of  claim 5 , wherein providing a catheter having a support system including a linear array of hollow rings and at least one strut secured to one side of each of the rings includes providing a catheter having a support system including a pair of struts secured to diametrically opposite sides of each of the rings.  
     
     
         7 . The method of  claim 5 , wherein providing a catheter having a support system including a linear array of hollow rings and at least one strut secured to one side of each of the rings includes providing a catheter having a support system which is formed of a resiliently deformable, shape-memory material.  
     
     
         8 . The method of  claim 1 , wherein providing a catheter includes providing a catheter having at least one steering tendon housed within the sheath, the steering tendon having a first end attached to the distal-end region of the sheath, and a second end located at the proximal region of the sheath.  
     
     
         9 . The method of  claim 8 , wherein manipulating the distal-end region of the catheter includes pulling the at least one steering tendon in a proximal direction to cause the sheath distal-end region to deflect.  
     
     
         10 . The method of  claim 1 , wherein: 
 providing a catheter includes providing a catheter having a handle coupled to the proximal end of the sheath; and    manipulating the distal-end region of the catheter includes rotating the handle.    
     
     
         11 . A method of delivering therapeutic treatment to a biological site, comprising: 
 providing a catheter having, 
 a sheath including a proximal region, a distal-end region, and a longitudinal centerline, and  
 a support system having a helical coil defining a proximal end, a distal end, a lumen there between and at least one strut secured to one side of the coil throughout the length of the coil, the support system sized to fit within the distal-end region of the sheath and configured to deflect laterally relative to the centerline and to resist axial compression along the centerline;  
   manipulating the distal end region of the catheter until the distal-end region of the catheter is proximate the biological site; and    providing therapeutic treatment to the biological site.    
     
     
         12 . The method of  claim 11 , wherein providing a catheter having a support system including a helical coil and at least one strut secured to one side of the coil throughout the length of the coil includes providing a catheter having a support system including a pair of struts secured to diametrically opposite sides of the coil.  
     
     
         13 . The method of  claim 11 , wherein providing a catheter having a support system including a helical coil and at least one strut secured to one side of the coil throughout the length of the coil includes providing a catheter having a support system which is formed of a resiliently deformable, shape-memory material.  
     
     
         14 . The method of  claim 11 , wherein: 
 providing a catheter includes providing a catheter having at least one steering tendon housed within the sheath, the steering tendon having a first end attached to the distal-end region of the sheath, and a second end located at the proximal region of the sheath; and    manipulating the distal-end region of the catheter includes pulling the at least one steering tendon in a proximal direction to cause the sheath distal-end region to deflect.    
     
     
         15 . The method of  claim 11 , wherein: 
 providing a catheter includes providing a catheter having a handle coupled to the proximal end of the sheath; and    manipulating the distal-end region of the catheter includes rotating the handle.    
     
     
         16 . A method of delivering therapeutic treatment to a biological site, comprising: 
 providing a catheter having, 
 a sheath including a proximal region, a distal-end region, and a longitudinal centerline, and  
 a support system having a linear array of hollow rings defining a proximal end, a distal end, a lumen there between and at least one strut secured to one side of each of the rings, the support system sized to fit within the distal-end region of the sheath and configured to deflect laterally relative to the centerline and to resist axial compression along the centerline;  
   manipulating the distal end region of the catheter until the distal-end region of the catheter is proximate the biological site; and    providing therapeutic treatment to the biological site.    
     
     
         17 . The method of  claim 16 , wherein providing a catheter having a support system including a linear array of hollow rings and at least one strut secured to one side of each of the rings includes providing a catheter having a support system including a pair of struts secured to diametrically opposite sides of each of the rings.  
     
     
         18 . The method of  claim 16 , wherein providing a catheter having a support system including a linear array of hollow rings and at least one strut secured to one side of each of the rings includes providing a catheter having a support system which is formed of a resiliently deformable, shape-memory material.  
     
     
         19 . The method of  claim 16 , wherein: 
 providing a catheter includes providing a catheter having at least one steering tendon housed within the sheath, the steering tendon having a first end attached to the distal-end region of the sheath, and a second end located at the proximal region of the sheath; and    manipulating the distal-end region of the catheter includes pulling the at least one steering tendon in a proximal direction to cause the sheath distal-end region to deflect.    
     
     
         20 . The method of  claim 16 , wherein: 
 providing a catheter includes providing a catheter having a handle coupled to the proximal end of the sheath; and    manipulating the distal-end region of the catheter includes rotating the handle.    
     
     
         21 . A catheter comprising: 
 a sheath including a proximal region, a distal-end region, and a longitudinal centerline; and    a support system having a proximal end, a distal end and a lumen there between, the support system sized to fit within the distal-end region of the sheath and configured to deflect laterally relative to the centerline and to resist axial compression along the centerline;    wherein the support system comprises a helical coil defining the lumen and at least one strut secured to one side of the coil throughout the length of the coil.    
     
     
         22 . A catheter comprising: 
 a sheath including a proximal region, a distal-end region, and a longitudinal centerline; and    a support system having a proximal end, a distal end and a lumen there between, the support system sized to fit within the distal-end region of the sheath and configured to deflect laterally relative to the centerline and to resist axial compression along the centerline;    wherein the support system comprises a linear array of hollow rings defining the lumen and at least one strut secured to one side of each of the rings.    
     
     
         23 . A catheter comprising: 
 a sheath including a proximal region, a distal-end region, and a longitudinal centerline;    a support system having a proximal end, a distal end and a lumen there between, the support system sized to fit within the distal-end region of the sheath and configured to deflect laterally relative to the centerline and to resist axial compression along the centerline; and    a ribbon isolation sleeve having a proximal end coupled to the distal-end of the support system.