Retrievable stent system

Abstract

A system for treating a body lumen including a first stent configured to be positioned in a body lumen and a second stent configured to be positioned in the lumen of the first stent prior to removing the first stent from the body lumen. The first stent includes a liner disposed radially inward of the tubular scaffold of the first stent to permit tissue ingrowth within a tissue ingrowth region defined between the liner and the tubular scaffold. The retrieval stent is configured to be expanded within the previously implanted first stent to cause tissue to recede from the tissue ingrowth region to facilitate removal of the first stent from the body lumen.

What is claimed is: 
     
         1 . A stent system, comprising:
 a first stent including an inner covering disposed within a lumen of the first stent, wherein the inner covering includes at least first portions attached to an inner surface of the first stent and one or more second portions extending radially inward of the inner surface to define one or more tissue ingrowth regions; and   a second stent configured to be disposed within the lumen of the first stent, the second stent having an outer surface configured to exert a radial outward force on the covering to cause tissue to recede from the one or more tissue ingrowth regions.   
     
     
         2 . The stent system of  claim 1 , wherein the second stent includes an outer covering disposed on the outer surface. 
     
     
         3 . The stent system of  claim 2 , wherein the outer covering is disposed on an entirety of the outer surface of the second stent. 
     
     
         4 . The stent system of  claim 1 , wherein the inner covering includes a plurality of first portions attached to the inner surface of the first stent. 
     
     
         5 . The stent system of  claim 4 , wherein the inner covering includes a plurality of second portions extending radially inward of the inner surface. 
     
     
         6 . The stent system of  claim 1 , wherein the one or more tissue ingrowth region extends circumferentially around the inner surface of the first stent. 
     
     
         7 . The stent system of  claim 1 , wherein the first stent includes a first flared end, a second flared end, and a middle region extending therebetween, wherein the one or more second portions of the inner covering are in the middle region. 
     
     
         8 . The stent system of  claim 7 , wherein the middle region has a first length and the second stent has a second length greater than the first length. 
     
     
         9 . The stent system of  claim 8 , wherein a profile along the outer surface of the second stent matches a profile of the inner surface of the first stent. 
     
     
         10 . The stent system of  claim 9 , wherein the second stent is configured to expand to have an outer diameter greater than an inner diameter of at least the middle region of the first stent. 
     
     
         11 . The stent system of  claim 7 , wherein the middle region of the first stent includes a first inner diameter, and wherein a diameter of the inner covering along the one or more tissue ingrowth regions includes a second inner diameter, and wherein the second inner diameter is greater than 25% of the diameter of the first inner diameter. 
     
     
         12 . The stent system of  claim 1 , wherein the first stent includes a first flared end, a second flared end, and a middle region extending therebetween, wherein the one or more second portions of the inner covering are in the first flared end, the second flared end, and the middle region. 
     
     
         13 . The stent system of  claim 1 , wherein the radial outward force is 0.10N to 2.5N. 
     
     
         14 . The stent system of  claim 1 , wherein the inner covering extends continuously between opposing first and second ends of the first stent. 
     
     
         15 . A system for treating a body lumen, comprising:
 an implantable stent, including:
 an expandable scaffold having a first end region, a second end region and a medial region extending between the first end region and the second end region; and 
 a liner directly attached to the scaffold at a first attachment location and a second attachment location, and wherein the liner is configured to be radially spaced from the inner surface of the expandable scaffold between the first attachment location and the second attachment location to define a tissue ingrowth region between the liner and the inner surface of the expandable scaffold; and 
   a retrieval stent configured to be disposed within a lumen of the implantable stent, wherein the retrieval stent is configured to exert a radially outward force on the liner.   
     
     
         16 . The system of  claim 15 , wherein the radial outward force exerted by the retrieval stent causes tissue ingrowth to recede from the tissue ingrowth region. 
     
     
         17 . The system of  claim 15 , wherein an unattached portion of the liner between the first attachment location and the second attachment location is configured to deflect radially inward from the inner surface of the expandable scaffold to permit tissue ingrowth in the tissue ingrowth region. 
     
     
         18 . The system of  claim 15 , wherein the tissue ingrowth region extends circumferentially around the inner surface of the expandable scaffold. 
     
     
         19 . The system of  claim 15 , wherein tissue ingrowth within the tissue ingrowth region is due to a hyperplastic response. 
     
     
         20 . The system of  claim 19 , wherein the liner is configured to limit the amount of tissue ingrowth into the tissue ingrowth region due to the hyperplastic response.