Radially-expandable stent and delivery system

A self-expanding radially expandable stent for implantation within a body lumen comprising:

• an elongated generally tubular body defining a passageway having a longitudinal axis, the body comprising at least one circumferential support section having a length along the longitudinal axis;
• each of the circumferential support sections comprising a substantially continuous element including a plurality of primary bends interconnected by struts, the primary bends being located on alternating ends of the support section around the circumference of the body, each of the struts connecting successive primary bends on opposite ends of the support section and having a midpoint generally located therebetween, wherein the stent is radially compressible into a compressed state and radially expandable into an expanded state in which the struts and primary bends in each of the support sections are arranged in a zigzag pattern;
• and
• means for reducing bending stress at the primary bends when the stent is in the compressed state.

A delivery system for implantation of a radially-expandable stent within a body lumen comprising:

• an inner tube having a proximal end and a distal end, the inner tube having an inner tube lumen formed therein, the inner tube lumen having an opening at the distal end of the inner tube;
• a cover sheath having a proximal end and a distal end, the cover sheath comprising a wall defining a cover sheath lumen, the inner tube located within the cover sheath lumen;
• a stent positioned about the inner tube at the distal end of the cover sheath;
• a first guidewire opening in the inner tube lumen, the first guidewire opening spaced from the distal end of the inner tube;
• a second guidewire opening in the wall of the cover sheath, the second guidewire opening located proximate the first guidewire opening;
• and
• a guide element having a distal end located within the inner tube lumen, the guide element extending between the first and second guidewire openings.

A method of deploying a stent within a body lumen comprising:

• a) providing a radially expandable stent on a delivery system comprising:
• an inner tube having a proximal end and a distal end, the inner tube having an inner tube lumen formed therein, the inner tube lumen having an opening at the distal end of the inner tube and a first guidewire opening in the inner tube lumen, the first guidewire opening spaced from the distal end of the inner tube;
• a stent positioned on the exterior surface of the inner tube at the distal end of the inner tube;
• a cover sheath having a proximal end and a distal end, the cover sheath comprising a wall defining a cover sheath lumen, the inner tube and stent located within the cover sheath lumen, the cover sheath further including a second guidewire opening in the wall of the cover sheath, the second guidewire opening located proximate the first guidewire opening in the inner tube;
• and
• a guide element having a distal end located within the inner tube lumen, the guide element extending between the first and second guidewire openings, wherein the guide element comprises a guide lumen formed in the distal end of the guide element;
• b) positioning a guidewire within a body lumen, wherein a proximal end of the guidewire extends out of the body lumen;
• c) inserting the proximal end of the guidewire into the inner tube lumen at the distal end of the inner tube;
• d) advancing the proximal end of the guidewire through the inner tube lumen towards the first guidewire opening and the distal end of the guide element, wherein at least a portion of the proximal end of the guidewire is advanced into the guide lumen in the distal end of the guide element;
• e) advancing the proximal end of the guidewire through the first and second guidewire openings;
• f) advancing the distal end of the inner tube and the stent over the guidewire towards the distal end of the guidewire, wherein the stent is positioned at a desired location within the body lumen;
• and
• g) deploying the stent at the desired location within the body lumen.

A method of deploying a stent within a body lumen comprising:

• a) providing a radially expandable stent on a delivery system comprising:
• an inner tube having a proximal end and a distal end, the inner tube having an inner tube lumen formed therein;
• a stent positioned on the exterior surface of the inner tube at the distal end of the inner tube;
• an expandable balloon located on the inner tube;
• an inflation lumen in fluid communication with the balloon, the inflation lumen extending from the proximal end of the delivery system to the balloon;
• and
• a cover sheath having a proximal end and a distal end, the cover sheath comprising a wall defining a cover sheath lumen, the inner tube, stent, and balloon located within the cover sheath lumen;
• b) positioning the inner tube, stent, balloon and cover sheath within a body lumen;
• c) moving the cover sheath proximally relative to the distal end of the inner tube to deploy the stent with the body lumen;
• and
• d) inflating the balloon within the stent.

A method of deploying a stent within a body lumen comprising:

• a) providing a radially expandable stent on a delivery system comprising:
• an inner tube having a proximal end and a distal end;
• a stent positioned on the exterior surface of the inner tube at the distal end of the inner tube;
• a cover sheath having a proximal end and a distal end, the cover sheath including a cover sheath lumen, the inner tube and stent located within the cover sheath lumen;
• and
• a support tube having a proximal end and a distal end, the support tube including a support tube lumen containing at least a portion of the proximal end of the cover sheath, the cover sheath being movable in the proximal and distal directions within the support tube lumen and the position of the inner tube being fixed relative to the position of the support tube;
• b) positioning a guide catheter within a body lumen;
• c) advancing the distal ends of the inner tube and the cover sheath through the guide catheter;
• d) fixing the position of the support tube relative to the guide catheter, wherein the positions of the distal end of the inner tube and the stent within the body lumen are also fixed relative to the guide catheter;
• and
• e) moving the cover sheath proximally to release the stent on the distal end of the inner tube, thereby deploying the stent within the body lumen.