Stent system for maintaining patency of a body lumen

A system for maintaining patency of a body lumen, comprising:

• a first endoprosthesis having a lumen extending from a first end to a second end, wherein the first endoprosthesis is configured to shift from a straightened configuration to a helical configuration defining a plurality of loops;
• and
• a second endoprosthesis configured to shift from a radially collapsed configuration toward a radially expanded configuration;
• wherein the plurality of loops defines a passage having an inner diameter;
• wherein the second endoprosthesis is configured to be disposed within the passage;
• wherein the second endoprosthesis has an outer diameter in the radially expanded configuration;
• wherein the outer diameter of the second endoprosthesis is within 20% of the inner diameter of the passage.

A method of maintaining patency of a body lumen, comprising:

• advancing a first endoprosthesis into a first body lumen in a straightened configuration;
• deploying the first endoprosthesis within the first body lumen in a helical configuration defining a plurality of loops;
• advancing a second endoprosthesis into the first body lumen in a radially collapsed configuration;
• and
• shifting the second endoprosthesis to a radially expanded configuration within the plurality of loops.