Bioabsorbable stents with reinforced filaments
According to an aspect of the present invention, a stent is provided, which contains at least one filament that has a longitudinal axis and comprises a bioabsorbable polymeric material. Polymer molecules within the bioabsorbable polymeric material are provided with a helical orientation which is aligned with respect to the longitudinal axis of the filament. The stent is at least partially bioabsorbed by a patient upon implantation or insertion of the stent into the patient.
1. A stent comprising:
at least one filament comprising a bioabsorbable polymeric material that has been molecularly oriented by longitudinally elongating and twisting the material at a temperature below its melting temperature,
wherein the stent is bioabsorbable by a patient upon implantation or insertion of the stent into the patient, and wherein the bioabsorbable polymeric material is elongated and twisted in the same process step, and
wherein the at least one filament comprises a therapeutic agent.
2. The stent of claim 1 , wherein the therapeutic agent is disposed within the at least one filament.
3. The stent of claim 1 , wherein the at least one filament is coated with the therapeutic agent.
4. The stent of claim 1 , wherein the therapeutic agent is covalently linked to a delivery substance.
5. The stent of claim 4 , wherein the delivery substance comprises polymer molecules.
6. The stent of claim 1 , wherein the therapeutic agent is non-covalently linked to a delivery substance.
7. The stent of claim 1 , wherein the stent has a length, and wherein the at least one filament is helically wound along at least a portion of the length of the stent.
8. The stent of claim 1 , wherein the stent comprises a plurality of filaments.
9. The stent of claim 8 , wherein the plurality of filaments are helically wound along at least a portion of the length of the stent.
10. The stent of claim 9 , wherein a plurality of filaments are helically wound in a first direction and a plurality of filaments are helically wound in an opposite direction.
11. The stent of claim 8 , wherein the plurality of the filaments are knitted filaments.
12. The stent of claim 8 , wherein the plurality of filaments are braided and helically wound along at least a portion of the length of the stent.
13. The stent of claim 1 , wherein the at least one filament is a braided filament.
14. The stent of claim 1 , wherein the at least one filament is a knitted filament.
15. The stent of claim 1 , wherein the oriented bioabsorbable polymeric material comprises a single bioabsorbable polymer or a blend of bioabsorbable polymers.
16. The stent of claim 1 , wherein the oriented bioabsorbable polymeric material comprises a polymer selected from poly(α-hydroxy acid) homopolymers, poly(α-hydroxy acid) copolymers and blends thereof.
17. The stent of claim 1 , wherein the oriented bioabsorbable polymeric material comprises a polymer selected from polyglycolide, poly-L-lactide, poly-D-lactide, poly-DL-lactide, and blends thereof.
18. The stent of claim 1 , wherein the oriented bioabsorbable polymeric material has a crystallinity ranging from 0.1 to 20%.
19. The stent of claim 1 , wherein the stent is selected from a coronary vascular stent, a peripheral vascular stent, a urethral stent, a ureteral stent, a biliary stent, a tracheal stent, a gastrointestinal stent and an esophageal stent.