Method of producing low profile stent and graft combination
View Patent ↗Large diameter self-expanding endoprosthetic devices, such as stents and stent grafts for delivery to large diameter vessels, such as the aorta, are disclosed having very small compacted delivery dimensions. Devices with deployed dimensions of 26 to 40 mm or more are disclosed that are compacted to extremely small dimensions of 5 mm or less, enabling percutaneous delivery of said devices without the need for surgical intervention. Compaction efficiencies are achieved by combining unique material combinations with new forms of restraining devices, compaction techniques, and delivery techniques. These inventive devices permit consistent percutaneous delivery of large vessel treatment devices. Additionally, small endoprosthetic devices are disclosed that can be compacted to extremely small dimensions for delivery through catheter tubes of less than 1 mm diameter.
1. A method of compacting an endoprosthesis into a compacted dimension comprising
providing a self-expanding endoprosthesis comprising a stent-element;
providing at least one internally tapered die proportioned to compact the endoprosthesis, the tapered die including multiple raised flutes and grooves therein to define a tapered surface;
passing the endoprosthesis through the tapered die to reduce its dimensions, the raised flutes and grooves causing the endoprosthesis to fold into uniform pleats in its compacted dimension.
2. The method of claim 1 that further comprises
passing the endoprosthesis through the tapered die at least one additional time.
3. The method of claim 2 that further comprises allowing the endoprosthesis to expand before passing it through the at least one tapered die at least one additional time.
4. The method of claim 1 that further comprises
subsequently passing the endoprosthesis through a second taper die having a smaller diameter.
5. The method of claim 1 that further comprises passing the endoprosthesis through a tapered die having a larger diameter prior to compacting in the at least one tapered die.
6. The method of claim 1 that further comprises
providing the stent-element with forward facing apices and rearward facing apices;
providing a tether line attached to or aligned with one or more of the apices;
pulling the endoprosthesis through the at least one tapered die using the tether line.
7. The method of claim 6 that further comprises
providing an actuation mechanism;
attaching the tether line to the actuation mechanism to pull the endoprosthesis through the at least one tapered die.
8. The method of claim 6 that further comprises
providing multiple tether lines;
aligning the tether lines with only forward facing apices so that when the tether lines are pulled through the grooves only the forward facing apices are visible on the outside of the compressed endoprosthesis.
9. The method of claim 1 that further comprises
positioning the flutes evenly around the tapered die so as to produce a uniform spacing of pleats around the compressed endoprosthesis.
10. The method of claim 9 that further comprises
providing a uniform spacing of grooves within the at least one endoprosthesis;
providing a tether line to correspond with each groove; and
passing the endoprosthesis through the tapered die using the tether lines.
11. The method of claim 1 that further comprises cooling the endoprosthesis prior to passing through the tapered die.