Shapeable or Steerable Guide Sheaths and Methods for Making and Using Them

Abstract

Apparatus and methods are provided for providing access to a body lumen, e.g., to deliver a pacing lead within a patient's heart. The apparatus includes a tubular member including a proximal end, a distal end sized for insertion into a body lumen, and a lumen extending therebetween. An elongate member extends from the distal end of the tubular member. An expandable sheath extends along at least a portion of the elongate member, the sheath being expandable from a contracted condition to facilitate insertion into a body lumen, and an enlarged condition wherein the sheath at least partially defines a lumen communicating with the tubular member lumen. A stylet or other shaped element is insertable into the elongate member for changing a shape of at least a distal tip of the elongate member, e.g., for accessing side branches extending from a body lumen, e.g., within a patient's coronary venous system.

1 . An apparatus for providing access to a body lumen, comprising:
 a tubular member comprising a proximal end, a distal end sized for insertion into a body lumen, a lumen extending between the proximal and distal ends;   an elongate member extending from the distal end of the tubular member, the elongate member terminating in a distal tip, the elongate member comprising a distal portion biased to assume a first nonlinear shape;   an expandable sheath extending along at least a portion of the elongate member, the sheath being expandable from a contracted condition to minimize a profile of the sheath to allow insertion along with the elongate member into a body lumen, and an enlarged condition wherein the sheath at least partially defines a lumen communicating with the tubular member lumen; and   an elongate element insertable into the distal portion of the elongate member for changing a shape of the distal portion.   
     
     
         2 . The apparatus of  claim 1 , wherein the element comprises one or more lumens extending between proximal and distal ends thereof, and wherein the elongate element is insertable into the lumen for changing the shape of the distal portion. 
     
     
         3 . The apparatus of  claim 1 , wherein the elongate element comprises a stylet biased to assume a second nonlinear shape different than the first nonlinear shape. 
     
     
         4 . The apparatus of  claim 1 , wherein the elongate element comprises a stylet that is malleable to a desired shape before insertion into the distal portion. 
     
     
         5 . A method for accessing a side branch of a body lumen using an apparatus including a tubular proximal portion and an expandable distal portion, the distal portion comprising an expandable sheath, the method comprising:
 advancing the distal portion into a patient's body to access a first location within a body lumen;   advancing a stylet into the distal portion to change a shape of the distal portion to a nonlinear shape;   accessing a branch extending from the first location using the distal portion in the nonlinear shape; and   advancing the distal portion into the branch to access a target location.   
     
     
         6 . The method of  claim 5 , further comprising advancing an elongate instrument through the proximal portion and the expandable sheath to deliver the instrument to the target location. 
     
     
         7 . The method of  claim 6 , further comprising removing the apparatus from the body lumen, while maintaining the instrument at the target location. 
     
     
         8 . The method of  claim 5 , wherein the distal portion is biased to a first nonlinear shape, and wherein advancing the stylet causes the distal portion to change from the first nonlinear shape to another shape to access the branch. 
     
     
         9 . The method of  claim 5 , wherein accessing the branch comprises manipulating the apparatus with the distal portion in the nonlinear shape to direct the distal portion and stylet into the branch, and advancing the distal portion over the stylet into the branch. 
     
     
         10 . The method of  claim 5 , wherein the branch extends at an acute angle from the first location, and wherein the nonlinear shape of the distal portion defines an acute angle for accessing the branch. 
     
     
         11 . The method of  claim 5 , wherein the first location comprises a vessel within a patient's coronary venous system, and the target location is an implantation site.