BIORESORBABLE SCAFFOLD FOR TREATMENT OF BIFURCATION LESION
Bioresorbable scaffolds for treatment of bifurcation lesion are described herein. Generally, an expandable scaffold may be fabricated from a high molecular weight isotropic PLLA material, wherein the scaffold incorporates one or more strain relief features which are configured to allow side branch treatment.
1 . (canceled)
2 . An expandable stent, comprising:
an implantable stent scaffold having a lumen defined therethrough;
wherein the implantable stent scaffold comprises a delivery configuration and a deployed configuration;
wherein the implantable stein scaffold is expandable from the delivery configuration into the deployed configuration;
wherein the implantable stent scaffold comprises at least one open cell defined along a wall of the implantable stein scaffold;
wherein the at least one open cell is expandable from a first cell configuration into a second cell configuration by an expansion device introduced therein; and
wherein the implantable stent scaffold is comprised of a bioresorbable polymer characterized by a molecular weight from about 259,000 g/mol to 2,120,000 g/mol and a crystallinity from about 20% to 40%.
3 . The stent of claim 1 , further comprising one or more struts, wherein the one or more struts is capable of being elongated from about 2% to 120% without cracking, fracturing, or failing during expansion of the open cell.
4 . The stent of claim 3 , wherein the one or more struts each define a strain relief area which is configured to stretch during expansion of the open cell.
5 . The stent of claim 1 , wherein the open cell is configured to be expanded into the second cell configuration having a shape selected from the group consisting of a hole, a flap, a window, a slot, and combinations thereof.
6 . The stent of claim 5 , wherein the open cell is configured to be expanded into a hole having a diameter between about 2.0 mm to 4.5 mm.
7 . The stern of claim 1 wherein the bioresorbable polymer is further characterized by a crystallinity from about 27% to 35%.
8 . The stent of claim 1 wherein the bioresorbable polymer is further characterized by crystalline regions and amorphous regions.
9 . The stern of claim 8 , wherein the crystalline regions are isotropic.
10 . The stent of claim 8 , wherein the crystalline regions are longitudinally oriented.
11 . The stent of claim 8 , wherein the crystalline regions are circumferentially oriented.
12 . The stent of claim 1 , wherein the physical properties of the bioresorbable polymer are isotropic.
13 . The stent of claim 1 , wherein the bioresorbable polymer is further characterized by a solvent content of less than about 100 ppm.
14 . The stent of claim 1 , wherein the bioresorbable polymer is further characterized by an intrinsic viscosity from about 4.3 dL/g to 8.4 dL/g
15 . The stent of claim 1 , wherein the bioresorbable polymer is further characterized by an elastic modulus from about 1000 MPa to 3000 MPa.
16 . The stent of claim 1 , wherein an applied load at failure of the implantable stent scaffold is from about 100 N to 300 N.
17 . The stent of claim 1 , wherein the bioresorbable polymer is configured to curve up to 180° about a 1 cm curvature radius without fracture formation or failure.
18 . The stent of claim 1 , wherein the implantable stent scaffold is characterized. by a radial strength of at least about 10 N per 1 cm length at about 20% compression
19 . The stent of claim 1 , wherein the implantable stent scaffold is characterized by a radial strength of at least about 0.1 N to 5 N per 1 cm at 20% compression.
20 . The stent of claim 1 , wherein the implantable stent scaffold is configured to withstand a strain of at least 150% without failure.
21 . The stent of claim 1 , wherein the implantable stent scaffold is configured to self-expand from the delivery configuration into the deployed configuration.