Method and apparatus for stenting

Abstract

A method and an apparatus to create a more favorable flow regime in a lumen. An artificial shape in the lumen is created to at least one of eliminate flow disturbances and enhance aspects of fluid flow through a treatment site.

What is claimed is: 
     
         1 . An expandable medical device for implantation in a body having a longitudinal axis along a direction of blood flow, said device comprising a first device segment directly connected around the circumference to a second device segment, said device having two tapers wherein the first device segment has a diverging configuration and the second device segment has a converging configuration. 
     
     
         2 . The expandable medical device of  claim 1 , wherein the first device segment has an opening having a first diameter and the second device segment has an opening having a second diameter. 
     
     
         3 . The expandable medical device of  claim 2 , wherein the first diameter and the second diameter are the same. 
     
     
         4 . The expandable medical device of  claim 2 , wherein the first diameter is larger than the second diameter. 
     
     
         5 . The expandable medical device of  claim 1 , wherein the device is self-expanding. 
     
     
         6 . The expandable medical device of  claim 1 , wherein the device is balloon-expandable. 
     
     
         7 . The expandable medical device of  claim 1 , wherein a cross-section of any device segment in a plane normal to the longitudinal axis thereof is circular. 
     
     
         8 . The expandable medical device of  claim 1 , further comprising a means for controlling a flow of blood. 
     
     
         9 . The expandable medical device of  claim 1 , wherein the device is configured to minimize a flow disturbance in the body. 
     
     
         10 . The expandable medical device of  claim 5 , wherein the device is re-positionable after delivery. 
     
     
         11 . The expandable medical device of  claim 1 , wherein the device is a stent structurally configured for implantation in a lumen of a blood vessel. 
     
     
         12 . The expandable medical device of  claim 1 , wherein the device further comprises a first straight section located at a first end of the device. 
     
     
         13 . The expandable medical device of  claim 12 , wherein the device further comprises a second straight section located at a second end of the device. 
     
     
         14 . The expandable medical device of  claim 13 , wherein the cross-sectional diameter of each of the straight sections is different. 
     
     
         15 . The expandable medical device of  claim 13 , wherein the cross-sectional diameter of each of the straight sections is the same. 
     
     
         16 . The expandable medical device of  claim 1 , wherein the first or second stent segments or both have a frustoconical shape. 
     
     
         17 . The expandable medical device of  claim 1 , wherein the envelope is configured for substantially eliminating flow separation in a lumen at the deployment site. 
     
     
         18 . The expandable medical device of  claim 1 , wherein the device is configured to change the shape of a lumen to an artificial tapered shape. 
     
     
         19 . The expandable medical device of  claim 1 , wherein the first device segment, second device segment, or both, have a continuous taper. 
     
     
         20 . The expandable medical device of  claim 1 , wherein the first device segment, second device segment, or both, have a stepped taper.