Medical device suitable for location in a body lumen

Abstract

A medical device suitable for location in a body lumen is movable between a first loaded configuration and a second loaded configuration. The device has an unloaded configuration which is intermediate the first loaded configuration and the second loaded configuration. The device can be a stent for deployment in a blood vessel.

1 . A medical device suitable for location in a body lumen, the device being movable between a first loaded configuration and a second loaded configuration, the device having an unloaded configuration intermediate the first loaded configuration and the second loaded configuration;
 wherein in the unloaded configuration at least part of a longitudinal axis of the device is curved;   wherein when the device is in use in a body lumen which is subject to deformation between an unloaded state and a loaded state, it adopts the first loaded configuration when the body lumen is in the unloaded state, and it adopts the second loaded configuration when the body lumen is deformed to the loaded state; and   wherein the device is configured so that when the device is deformed through an angle of 45 degrees between the first loaded configuration and the second loaded configuration, a maximum strain in the device, at any stage at or between the first and second loaded configurations, is less than or equal to 0.4%.   
     
     
         25 . A device as claimed in  claim 1 , wherein the device is deformable between the first loaded configuration and the second loaded configuration. 
     
     
         26 . A device as claimed in  claim 1 , wherein the device is bendable between the first loaded configuration and the second loaded configuration. 
     
     
         27 . A device as claimed in  claim 1 , wherein the device is twistable between the first loaded configuration and the second loaded configuration. 
     
     
         28 . A device as claimed in  claim 1 , wherein the device is compressible between the first loaded configuration and the second loaded configuration. 
     
     
         29 . A device as claimed in  claim 1 , wherein in the unloaded configuration at least part of the longitudinal axis of the device is curved in a two-dimensional plane. 
     
     
         30 . A device as claimed in  claim 29 , wherein the device has plural curves in the two-dimensional plane. 
     
     
         31 . A device as claimed in  claim 29  wherein the plural curves comprise a sinusoidal or substantially zigzag shape. 
     
     
         32 . A device as claimed in  claim 1 , wherein in the unloaded configuration at least part of the longitudinal axis of the device is curved in three-dimensional space. 
     
     
         33 . A device as claimed in  claim 32 , wherein the curvature is helical. 
     
     
         34 . A device as claimed in  claim 1 , wherein the maximum strain is less than or equal to 0.3%. 
     
     
         35 . A device as claimed in  claim 1 , configured so that when the device is axially compressed by 6% from the first loaded configuration to the second loaded configuration, the maximum strain in the device, at any stage at or between the first and second loaded configurations, is less than or equal to 0.7%. 
     
     
         36 . A device as claimed in  claim 1 , wherein the unloaded configuration is approximately midway between the first loaded configuration and the second loaded configuration. 
     
     
         37 . A device as claimed in  claim 1 , wherein the device comprises means to align the device relative to a body lumen. 
     
     
         38 . A device as claimed in  claim 37 , wherein the alignment means comprises means to visualise the device. 
     
     
         39 . A device as claimed in  claim 1 , wherein the device is suitable for location in a blood vessel. 
     
     
         40 . A device as claimed in  claim 39 , wherein the device comprises a stent suitable for deployment in a blood vessel. 
     
     
         41 . A device as claimed in  claim 40 , wherein the stent has a longitudinal axis with a length of at least 50 mm. 
     
     
         42 . A device as claimed in  claim 1 , wherein the device is made of Nitinol. 
     
     
         43 . A medical device suitable for location in a body lumen, the device being movable between a first loaded configuration and a second loaded configuration, the device having an unloaded configuration intermediate the first loaded configuration and the second loaded configuration;
 wherein in the unloaded configuration at least part of a longitudinal axis of the device is curved;   wherein when the device is in use in a body lumen which is subject to deformation between an unloaded state and a loaded state, it adopts the first loaded configuration when the body lumen is in the unloaded state, and it adopts the second loaded configuration when the body lumen is deformed to the loaded state; and   wherein the device is configured so that when the device is axially compressed by 6% from the first loaded configuration to the second loaded configuration, a maximum strain in the device, at any stage at or between the first and second loaded configurations, is less than or equal to 0.7%.   
     
     
         44 . A device as claimed in  claim 43 , wherein the maximum strain is less than or equal to 0.5%. 
     
     
         45 . A device as claimed in  claim 43 , wherein the device is movable between the first and second loaded configurations according to a feature selected from the following list: deformation, bending , twisting, compression, 
     
     
         46 . A device as claimed in  claim 43 , wherein in the unloaded configuration at least part of the longitudinal axis of the device is curved in three-dimensional space. 
     
     
         47 . A device as claimed in  claim 43 , wherein the device comprises means to align the device relative to a body lumen. 
     
     
         48 . A device as claimed in  claim 47 , wherein the alignment means comprises means to visualise the device. 
     
     
         49 . A device as claimed in  claim 43 , wherein the device comprises a stent suitable for deployment in a blood vessel.