Implantable medical device detachment system with flexible braid section

Abstract

The disclosed technology includes a detachment system for delivering an implantable medical device to a target location of a body vessel including a proximal delivery tube, a distal delivery tube, and a braid segment disposed between. The distal tube includes a proximal end, a distal end, and a compressible portion of the tube itself, between the proximal and distal ends which is axially movable from a compressed to an elongated condition. The proximal tube has a proximal end and a distal end. The braid segment is formed from a plurality of wires. An engagement system engages and deploys the implantable medical device engaged at the distal end of the distal tube.

1 . A detachment system for delivering an implantable medical device to a target location of a body vessel (BV), comprising:
 a generally hollow, relatively stiff proximal tube having a proximal end and a distal end, the distal end comprising a flexible section;   a generally hollow, relatively flexible distal tube comprising:   
       a proximal end; 
       a distal end; and 
       a compressible portion of the relatively flexible distal tube itself which is axially movable from a compressed condition to an elongated condition; 
       a flexible braid segment disposed between the proximal end of the relatively flexible distal tube and the flexible section of the distal end of the relatively stiff proximal tube, the flexible braid segment formed from a plurality of wires; and
 an engagement system configured to engage and deploy the implantable medical device disposed at the distal end of the distal tube, 
 
       wherein the flexible braid segment is more flexible than each of the relatively flexible distal tube and the relatively stiff proximal tube. 
     
     
         2 . The detachment system of  claim 1 , wherein the flexible braid segment is concentrically disposed around a polymer liner. 
     
     
         3 . The detachment system of  claim 1 , wherein a polymer sleeve is positioned over at least a portion of the proximal tube, the braid segment, and at least a portion of the distal tube. 
     
     
         4 . The detachment system of  claim 1 , wherein the polymer sleeve includes one or more hydrophilic coatings. 
     
     
         5 . The detachment system of  claim 1 , wherein the polymer sleeve has a wall having a thickness of between approximately 0.02 millimeters and approximately 0.08 millimeters. 
     
     
         6 . The detachment system of  claim 1 , wherein the flexible braid segment includes between approximately 8 and approximately 16 wires. 
     
     
         7 . The detachment system of  claim 1 , wherein the plurality of wires have a pick per inch of between approximately 50 and approximately 100. 
     
     
         8 . The detachment system of  claim 1 , wherein the compressible portion of the relatively flexible distal tube is a spiral-cut portion of the relatively flexible distal tube. 
     
     
         9 . The detachment system of  claim 1 , wherein the flexible section of the distal end of the relatively stiff proximal tube comprises a spiral-cut portion. 
     
     
         10 . The detachment system of  claim 1 , wherein the engagement system is configured to:
 move the compressible portion to the compressed condition when engaging the implantable medical device; and   deploy the implantable medical device when releasing the compressible portion to the elongated condition.   
     
     
         11 . The detachment system of  claim 1 , wherein the compressible portion is adapted to automatically move to the elongated condition when the engagement system is disengaged from the implantable medical device. 
     
     
         12 . A method of detaching an implantable medical device, comprising forming a compressible portion on a proximal end of a relatively flexible distal tube;
 forming a flexible portion on a distal end of a relatively stiff proximal tube;   attaching a flexible braid assembly to the distal end of the relatively stiff proximal tube and the proximal end of the relatively flexible distal tube;   
       sliding a polymer sleeve over at least a portion of the flexible section of the relatively stiff proximal tube, the entirety of the flexible braid assembly, and the entirety of the relatively flexible distal tube; and 
       engaging the implantable medical device with an engagement system, 
       wherein the flexible braid segment is more flexible than each of the relatively flexible distal tube and the relatively stiff proximal tube. 
     
     
         13 . The detachment method of  claim 12 , wherein a polymer sleeve is positioned over at least a portion of the proximal tube, the braid segment, and at least a portion of the distal tube. 
     
     
         14 . The detachment method of  claim 13 , further comprising engaging the polymer sleeve to the implantable medical device. 
     
     
         15 . The detachment method of  claim 13 , further comprising coating the polymer sleeve with one or more hydrophilic coatings. 
     
     
         16 . The detachment method of  claim 12 , further comprising wrapping the flexible braid assembly around a polymer liner prior to attaching the flexible braid assembly to the distal end of the relatively stiff proximal tube and the proximal end of the relatively flexible distal tube. 
     
     
         17 . The detachment method of  claim 12 , wherein the engagement system comprises a locking member, and a loop wire,
 wherein engaging the implantable medical device with the engagement system further comprises using the loop wire with the locking member to engage the implantable medical device; and
 wherein the applying step further comprises applying force to the loop wire to move the compressible portion to a compressed condition. 
   
     
     
         18 . The detachment method of  claim 17 , further comprising:
 applying a force on the locking member;   
       disengaging the implantable medical device; and 
       allowing the compressible portion to return to an elongated condition. 
     
     
         19 . The detachment method of  claim 12 , wherein forming the compressible portion on the relatively flexible distal tube includes spiral-cutting a portion of the relatively flexible distal tube. 
     
     
         20 . The detachment method of  claim 12 , further comprising deploying the implantable medical device by moving the compressible portion to an elongated condition.