Stent delivery system
One preferred embodiment includes a stent delivery system including a retractable sheath and an outer stability sheath. The stability sheath freely rotates relative to the retractable sheath, relieving compression forces caused by twisting of stability sheath in when in a tortuous conformation.
1. A stent delivery system, comprising:
a first tubular member having a distal end sized and shaped to receive a stent;
a second tubular member longitudinally slidable over said first tubular member;
a third tubular member at least partially disposed over said second tubular member, said third tubular member rotatable relative to said first tubular member and to said second tubular member, a disc member provided near the proximal end of the third tubular member; and
a handle body defining a cavity in which the disc member of said third tubular member is positioned to permit free rotation of the third tubular member relative to the handle body and said second tubular member when in use for stent delivery, the handle body coupled to said second tubular member to retract said second tubular member relative to said first tubular member, wherein the handle body includes at least three different controls for retracting said second tubular member relative to said first tubular member, each of the at least three different controls configured to provide the user with a different retraction ratio.
2. The system of claim 1 , the disc member being a circular disc member and the cavity being a circular cavity.
3. The system of claim 1 , wherein the disc member is bonded to the third tubular member.
4. The system of claim 1 , wherein the disc member is integrally formed with the third tubular member.
5. The system of claim 1 , further comprising a strain relief member at least partially disposed over the third tubular member.
6. The system of claim 5 , wherein the inner surface of the strain relief member includes a low friction coating.
7. The system of claim 6 , wherein the outer surface of the third tubular member includes a low friction coating.
8. The system of claim 5 , further comprising a lubricant disposed between the inner surface of the strain relief member and the outer surface of the third tubular member.
9. The system of claim 1 , wherein the handle body is configured to retract said second tubular member relative to said first tubular member to uncover and deploy the stent.
10. A stent delivery system, comprising:
a first tubular member having a distal end sized and shaped to receive a stent;
a second tubular member longitudinally slidable over said first tubular member;
a stability sheath at least partially disposed over said second tubular member, said stability sheath including a plurality of circumferential crumple zones, each crumple zone longitudinally compressible relative to said first tubular member and to said second tubular member;
a strain relief member at least partially disposed over the stability sheath at a location proximal the plurality of crumple zones; and
a handle body coupled to said second tubular member to retract said second tubular member relative to said first tubular member, wherein the handle body includes at least three different controls for retracting said second tubular member relative to said first tubular member, each of the at least three different controls configured to provide the user with a different retraction ratio.
11. The system according to claim 10 , wherein the plurality of crumple zones are positioned at the proximal end of the stability sheath adjacent the strain relief member.
12. The system according to claim 10 , wherein the plurality of crumple zones in combination compress longitudinally a length at least equal to the length of the stent to be deployed.
13. The system according to claim 10 , wherein the plurality of crumple zones longitudinally compress by folding or buckling, each crumple zone having a decreased thickness relative to a thickness of the stability sheath adjacent the plurality of crumble zones.
14. The system according to claim 10 , wherein each crumple zone is formed by a circumferential crease in the stability sheath.
15. The system according to claim 10 , wherein each crumple zone is formed by perforations in the stability sheath.
16. The system of claim 10 , wherein a proximal end of the stability sheath extends into an interior of the handle body.