Stent delivery system with a fixed guide wire
View Patent ↗The present invention is a stent delivery system that uses a short section of a guide wire that is fixedly attached to a distal section of a balloon angioplasty catheter. By not having a guide wire that slides through the balloon of the balloon angioplasty catheter, the balloon on which the stent is mounted can have a reduced diameter. Therefore, the outside diameter of the undeployed stent mounted onto that balloon is also minimized. This provides a minimum profile, i.e., a minimum outside diameter, for the stent. A minimum profile at the distal section of the stent delivery system is highly advantageous for improving the percentage of cases that can be treated by means of direct stenting; i.e., without requiring pre-dilation of a stenosis.
1. A system for placing a stent in a vessel of the human body comprising:
a catheter having a distal section with a balloon located at the distal section;
a balloon expandable stent mounted onto the inflatable balloon, the stent being adapted for implantation into a vessel of the human body; and
an unprotected guide wire attached to and extending distally from the distal section of the balloon catheter.
2. The stent delivery system of claim 1 wherein the guide wire is substantially straight over its entire length.
3. The stent delivery system of claim 1 wherein the guide wire has a distal section that is substantially curved.
4. The stent delivery system of claim 1 wherein the guide wire has an outside diameter that is less than 0.035 inches.
5. The stent delivery system of claim 1 wherein the length of the guide wire extending in a bare manner beyond the distal section of the balloon catheter is less than 5 cm.
6. The stent delivery system of claim 1 wherein the stent is mechanically crimped onto the balloon.
7. The stent delivery system of claim 1 wherein the stent is nested onto the balloon.
8. The stent delivery system of claim 1 wherein the balloon has a longitudinal axis and the balloon is wrapped in a spiral around the balloon's longitudinal axis prior to placement of the stent onto the balloon.
9. The stent delivery system of claim 1 wherein the balloon is folded with a multiplicity of wings as is conventional for a balloon of a balloon angioplasty catheter.
10. The stent delivery system of claim 1 wherein the balloon has a proximal section that has the shape of a frustum of a cone when the balloon is fully inflated and the catheter includes a proximal elastic band that is wrapped around the proximal section of the balloon prior to balloon inflation.
11. The stent delivery system of claim 1 wherein the balloon has a distal section that has the shape of a frustum of a cone when the balloon is fully inflated and the catheter includes a distal elastic band that is wrapped around the distal section of the balloon prior to balloon inflation.
12. The stent delivery system of claim 1 wherein the balloon has a proximal end that is attached to a central tube having a central lumen through which balloon inflation fluid can be injected or removed to respectively inflate or deflate the balloon.
13. The stent delivery system of claim 1 wherein the balloon overhang length beyond each edge of the stent is less than 1.0 mm.
14. The stent delivery system of claim 1 wherein the balloon overhang length beyond each edge of the stent is less than 0.5 mm.
15. The stent delivery system of claim 1 wherein the longitudinal length of the stent when deployed is approximately equal to the length of the cylindrical section of the inflated balloon thereby resulting in an approximately zero length of balloon overhang beyond the edges of the stent.