Stents and related methods

Abstract

Stents are disclosed herein. In some embodiments stents within the scope of this disclosure may comprise a first flared end and second flared end. In some embodiments, a profile of each of the first flared end and the second flared end may circumscribe a portion of separate elliptical arcs. In some embodiments, the stents are formed from braided or woven wires having a constant pitch along a middle region and continuously varying pitches along the first flared end and the second flared end. Methods of manufacturing stents are disclosed herein. Methods of using stents are also disclosed herein.

1 - 20 . (canceled) 
     
     
         21 . A stent comprising:
 a hollow cylindrical body having an interior dimension and an exterior dimension and comprising a middle region that extends to a first flared end and also extends to an opposing second flared end,   the first flared end comprising a first inner shoulder, a first crest, a first outer taper, and a first opening, wherein the first inner shoulder extends from one end of the middle region to the first crest, wherein a diameter of the first crest is greater than a diameter of the middle region, wherein the first outer taper extends from the first crest to the first opening, wherein the first opening provides a first boundary between the interior dimension and the exterior dimension,   the hollow cylindrical body characterized by a longitudinal plane that bisects the hollow cylindrical body along its longitudinal axis, characterized by a first perpendicular plane that encompasses a circle defined by the first crest, and wherein the first perpendicular plane is perpendicular to the longitudinal plane,   wherein a profile of at least a portion of the first inner shoulder, the first crest, and at least a portion of the first outer taper circumscribes a portion of a first elliptical arc that lies in the longitudinal plane, wherein the first elliptical arc includes an upper antipodal point of the first ellipse, wherein a lower antipodal point of the first ellipse is outwardly offset along the longitudinal plane relative to the first perpendicular plane and the middle region.   
     
     
         22 . The stent of  claim 21 , wherein the second flared end comprises a second inner shoulder, a second crest, a second outer taper, and a second opening, wherein the second inner shoulder extends from one end of the middle region to the second crest, wherein a diameter of the second crest is greater than a diameter of the middle region, wherein the second outer taper extends from the second crest to the second opening, wherein the second opening provides a second boundary between the interior dimension and the exterior dimension, 
     
     
         23 . The stent of  claim 22 , wherein the hollow cylindrical body is further characterized by a second perpendicular plane that encompasses a circle defined by the second crest, the second perpendicular plane also perpendicular to the longitudinal plane, and
 wherein a profile of at least a portion of the second inner shoulder, the second crest, and at least a portion of the second outer taper circumscribes a portion of a second elliptical arc of a second ellipse that lies in the longitudinal plane, wherein the second elliptical arc includes an upper antipodal point of the second ellipse, wherein a lower antipodal point of the second ellipse is outwardly offset along the longitudinal plane relative to the second perpendicular plane and the middle region.   
     
     
         24 . The stent of  claim 21 , wherein a diameter of the first opening is greater than the diameter of the middle region, but less than the diameter of the first crest. 
     
     
         25 . The stent of  claim 21 , wherein the hollow cylindrical body comprises braided or woven wires having a uniformly varying pitch along the first inner shoulder that is continuously decreasing from the middle region to the first crest. 
     
     
         26 . The stent of  claim 21 , wherein the hollow cylindrical body comprises braided or woven wires having a uniformly varying pitch along the first outer taper that is continuously increasing from the first crest to the first opening. 
     
     
         27 . The stent of  claim 21 , wherein the lower antipodal point of the first ellipse is outwardly offset along the longitudinal plane relative to the first perpendicular plane and the middle region by about 5 degrees to about 60 degrees. 
     
     
         28 . The stent of  claim 21 , wherein the first outer taper comprises a suture line that surrounds the first opening, wherein the suture line is configured to facilitate stretching and elongation of the hollow cylindrical body when the suture line is pulled in the direction of the longitudinal axis and outwardly away from the first perpendicular plane. 
     
     
         29 . The stent of  claim 21 , wherein the braided or woven wires comprise a uniformly varying pitch along the first outer taper that is configured to allow the braided or woven wires at the first opening to expand equal to the diameter of the first crest. 
     
     
         30 . A stent comprising:
 a hollow cylindrical body having an interior dimension and an exterior dimension and comprising a middle region that extends to a first flared end and also extends to an opposing second flared end,   the first flared end comprising a first inner shoulder, a first crest, a first outer taper, and a first opening, wherein the first inner shoulder extends from one end of the middle region to the first crest, wherein a diameter of the first crest is greater than a diameter of the middle region, wherein the first outer taper extends from the first crest to the first opening, wherein a diameter of the first opening is greater than the diameter of the middle region but less than the diameter of the first crest, and wherein the first opening provides a first boundary between the interior dimension and the exterior dimension,   the second flared end comprising a second inner shoulder, a second crest, a second outer taper, and a second opening, wherein the second inner shoulder extends from one end of the middle region to the second crest, wherein a diameter of the second crest is greater than a diameter of the middle region, wherein the second outer taper extends from the second crest to the second opening, wherein a diameter of the second opening is greater than the diameter of the middle region but less than the diameter of the second crest, and wherein the second opening provides a second boundary between the interior dimension and the exterior dimension,   wherein a profile of at least a portion of the first inner shoulder, the first crest, and at least a portion of the first outer taper circumscribes a portion of a first arc that lies in the longitudinal plane, and wherein a profile of at least a portion of the second inner shoulder, the second crest, and at least a portion of the second outer taper circumscribes a portion of a second arc that lies in the longitudinal plane.   
     
     
         31 . The stent of  claim 30 , wherein the hollow cylindrical body comprises braided or woven wires having a constant pitch along a length of the middle region, the braided or woven wires having a uniformly varying pitch along the first inner shoulder, the braided or woven wires having a constant pitch at the first crest, the braided or woven wires having a uniformly varying pitch along the first outer taper, the braided or woven wires having a uniformly varying pitch along the second inner shoulder, the braided or woven wires having a constant pitch at the second crest, and the braided or woven wires having a uniformly varying pitch along the second outer taper. 
     
     
         32 . The stent of  claim 31 , wherein the uniformly varying pitch along the first and second inner shoulders is continuously decreasing from the middle region to the first and second crests, respectively. 
     
     
         33 . The stent of  claim 31 , wherein the uniformly varying pitch along the first outer taper is continuously increasing from the first crest to the first opening and wherein the uniformly varying pitch along the second outer taper is continuously increasing from the second crest to the second opening. 
     
     
         34 . The stent of  claim 31 , wherein the uniformly varying pitch along the first outer taper is configured to allow the braided or woven wires at the first opening to expand equal to the diameter of the first crest and wherein the uniformly varying pitch along the second outer taper is configured to allow the braided or woven wires at the second opening to expand equal to the diameter of the second crest. 
     
     
         35 . The stent of  claim 31 , wherein individual braided or woven wires are braided or woven starting from the second flared end, through the middle region, through the first flared end, to the first opening, back through the first flared end, back through the middle region, and back through the second flared end. 
     
     
         36 . The stent of  claim 35 , wherein for braided wires a beginning and an end of each of the individual braided wires overlap with each other or a different wire end underneath a crossover wire along the second outer taper and not at the second opening of the second flared end, and wherein for woven wires a beginning and an end of each of the individual woven wires overlap with each other underneath a crossover wire along the second outer taper and not at the second opening of the second flared end. 
     
     
         37 . The stent of  claim 35 , wherein for braided wires a beginning and an end of each of the individual braided wires overlap with each other or a different wire end underneath a crossover wire along the middle region, and wherein for woven wires a beginning and an end of each of the individual woven wires overlap with each other underneath a crossover wire along the middle region. 
     
     
         38 . A method of making a stent, the method comprising:
 providing a first mandrel having an outer cylindrical surface with a constant cylindrical shape and having a diameter equal to the diameter of a desired middle region of a stent; and   braiding or weaving wire comprised of shape-memory material around the outer cylindrical surface of the first mandrel to form braided or woven wires of the stent, wherein the braided or woven wires have a first end region, a middle region, and a second end region, wherein the middle region comprises a constant pitch and the first and second end regions have continuously varying pitches.   
     
     
         39 . The method of  claim 38 , further comprising:
 providing a second mandrel having a shape similar to a desired shape of the stent when the stent is in an unstretched and unelongated state, wherein the second mandrel comprises a middle cylindrical region, a first flared end, and a second flared end, wherein a diameter of the middle cylindrical region matches the diameter of the outer cylindrical surface of the first mandrel, and wherein a first crest of the first flared end and a second crest of the second flared end each have a diameter greater than the diameter of the middle cylindrical region;   removing the braided or woven wire from the first mandrel;   placing the braided or woven wire over the second mandrel so that the first end region aligns with the first flared end of the second mandrel, the middle region aligns with the middle cylindrical region of the second mandrel, and the second end region aligns with the second flared end of the second mandrel; and   heat-setting the braided or woven wires.   
     
     
         40 . The method of  claim 39 , further comprising:
 removing the braided or woven wire from the second mandrel;   providing a third mandrel having a shape similar to the second mandrel;   placing the braided or woven wire over the third mandrel; and   coating the braided or woven wire.