Guide catheters for accessing cardiac sites

Abstract

A method and apparatus for introducing a cardiac lead to an implantation site that includes a catheter body having an outer wall and a distal leader and having a proximal portion extending from the first proximal end to a second distal end. An inner member is positioned within an outer lumen of the catheter body and is spaced from the outer wall to form a first inner lumen for receiving a guide tool inserted therein and a second lumen for receiving the cardiac lead while the guide tool is positioned within the first inner lumen. A distal end of the inner member forms a first opening at a distal end of the first inner lumen and a second opening at a distal end of the second inner lumen, the first opening and the second opening positioned proximal the distal leader.

1 . A guide catheter for introducing a cardiac lead having a distal fixation mechanism through a pathway from an incision to an implantation site, comprising: 
 an elongated catheter body extending between a first proximal end and a first distal end, the catheter body including an outer wall and a distal leader and having a proximal portion extending from the first proximal end to a second distal end, the distal leader extending distally from the second distal end, and the outer wall extending along the proximal portion and the distal leader and forming an outer lumen extending through the proximal portion and the distal leader; and    an inner member positioned within the outer lumen and having a third distal end, the inner wall spaced from the outer wall to form a first inner lumen for receiving a guide tool inserted therein to aid in steering the catheter body through the pathway and a second lumen for receiving the cardiac lead while the guide tool is positioned within the first inner lumen, the third distal end forming a first opening at a distal end of the first inner lumen and a second opening at a distal end of the second inner lumen, the first opening and the second opening positioned proximal the distal leader.    
   
   
       2 . The guide catheter of  claim 1 , wherein the outer wall includes a tapered portion for directing advancing of a distal tip of the guide tool from a retracted position proximal the third distal end to an extended position within the outer lumen of the distal leader while a distal tip of the lead is positioned in the retracted position, and for directing advancing of the distal tip of the lead from the retracted position to the extended position while the distal tip of the guide tool is positioned in the retracted position.  
   
   
       3 . The guide catheter of  claim 1 , wherein the distal fixation mechanism includes one of a fixation helix adapted to be screwed through a vessel wall into the myocardium, a hook, and a prong adapted to be extended through the vessel wall into the myocardium.  
   
   
       4 . The guide catheter of  claim 1 , further comprising a tubular member extending within the outer lumen along the proximal portion, wherein the inner member is formed by the tubular member.  
   
   
       5 . The guide catheter of  claim 1 , wherein the outer wall includes a tapered portion extending from a tapered portion proximal end to the second distal end so that a lumen opening formed at the second distal end is axially aligned with and has a diameter approximately equal to a diameter of the outer lumen formed by the outer wall along the distal leader, and wherein the third distal end is proximal the tapered portion.  
   
   
       6 . The guide catheter of  claim 1 , wherein the guide tool is one of a guidewire, a stiffening stylet, and a steerable stylet.  
   
   
       7 . The guide catheter of  claim 1 , wherein the distal fixation mechanism includes one of a fixation helix adapted to be screwed through a vessel wall into the myocardium, a hook, and a prong adapted to be extended through the vessel wall into the myocardium.  
   
   
       8 . A method of introducing a cardiac lead having a distal fixation mechanism through a pathway from an incision to an implantation site, comprising: 
 positioning one of a guide tool and the lead in a first inner lumen of a guide catheter formed by an inner member positioned within a portion of an outer lumen extending through a proximal portion of the guide catheter, the inner member formed by an outer wall of the guide catheter and spaced from the outer wall;    positioning the other of the guide tool and the lead in a second inner lumen of the guide catheter formed by the inner member and the outer wall;    advancing the guide catheter through the pathway;    advancing a distal tip of the guide tool from a retracted position proximal to a distal end of the inner member to an extended position within and extending outward from a portion of the outer lumen formed by the outer wall along a distal leader extending distally from the proximal portion of the guide catheter and to the implantation site;    advancing the guide catheter over the guide tool to the implantation site;    advancing the guide tool from the extended position to the retracted position; and    advancing the fixation mechanism of the lead from the retracted position to the extended position.    
   
   
       9 . The method of  claim 8 , further comprising fixedly engaging the fixation mechanism at the implantation site.  
   
   
       10 . The method of  claim 8 , wherein the outer wall includes a tapered portion extending from a tapered portion proximal end to a distal end of the proximal portion of the guide catheter so that a lumen opening formed at the distal end of the proximal portion is axially aligned with and has a diameter approximately equal to a diameter of the outer lumen formed by the outer wall along the distal leader, and wherein the distal end of the inner member is proximal the tapered portion and the tapered portion directs the advancing of the guide tool and the lead between the retracted position and the extended position.  
   
   
       11 . The method of  claim 8 , wherein the guide tool is one of a guidewire, a stiffening stylet, and a steerable stylet.  
   
   
       12 . The method of  claim 8 , wherein the inner wall is formed by a tubular member extending within the outer lumen along the proximal portion of the guide catheter.  
   
   
       13 . The method of  claim 8 , wherein the distal fixation mechanism includes one of a fixation helix adapted to be screwed through a vessel wall into the myocardium, a hook, and a prong adapted to be extended through the vessel wall into the myocardium.  
   
   
       14 . The method of  claim 8 , wherein the inner member is formed by a tubular member  
   
   
       15 . A guide catheter for introducing a cardiac lead having a distal fixation mechanism through a pathway from an incision to an implantation site, comprising: 
 an elongated catheter body extending between a first proximal end and a first distal end, the catheter body including an outer wall and a distal leader and having a proximal portion extending from the first proximal end to a second distal end, the distal leader extending distally from the second distal end, and the outer wall extending along the proximal portion and the distal leader and forming an outer lumen extending through the proximal portion and the distal leader; and    an inner member positioned within the outer lumen and having a third distal end, the inner wall spaced from the outer wall to form a first inner lumen for receiving a guide tool inserted therein to aid in steering the catheter body through the pathway and a second lumen for receiving the cardiac lead while the guide tool is positioned within the first inner lumen, the third distal end forming a first opening at a distal end of the first inner lumen and a second opening at a distal end of the second inner lumen, the first opening and the second opening positioned proximal the distal leader, wherein the outer wall includes a tapered portion extending from a tapered portion proximal end to the second distal end so that a lumen opening formed at the second distal end is axially aligned with and has a diameter approximately equal to a diameter of the outer lumen formed by the outer wall along the distal leader, and wherein the third distal end is proximal the tapered portion, the tapered portion directing advancing of a distal tip of the guide tool from a retracted position proximal the third distal end to an extended position within the outer lumen of the distal leader while a distal tip of the lead is positioned in the retracted position, and directing advancing of the distal tip of the lead from the retracted position to the extended position while the distal tip of the guide tool is positioned in the retracted position.    
   
   
       16 . The guide catheter of  claim 15 , wherein the distal fixation mechanism includes one of a fixation helix adapted to be screwed through a vessel wall into the myocardium, a hook, and a prong adapted to be extended through the vessel wall into the myocardium.  
   
   
       17 . The guide catheter of  claim 15 , further comprising a tubular member extending within the outer lumen along the proximal portion, wherein the inner wall is formed by the tubular member.  
   
   
       18 . The guide catheter of  claim 15 , wherein the guide tool is one of a guidewire, a stiffening stylet, and a steerable stylet.