Biomaterial

A medical device for placement in a gastrointestinal tract, the device comprising:

• a valve member comprising a biomimetic viscoelastic polymeric foam material, the valve member having a proximal outer support region with a rim;
• at least four valve leaflets;
• a main body region extending between the support rim and the valve leaflets, the main body region having a generally concave outer face and a generally convex inner face the valve member having a normally closed configuration in which the leaflets are engaged at a region of co-aption of the valve leaflets and an open configuration;
• the main body region of the valve member having a first thickness, the valve leaflets at the region of co-aption having a second thickness which is greater than the first thickness to define a reinforced region which extends in a longitudinal direction;
• and
• a support member which is configured to engage with a wall of the gastrointestinal tract, the rim of the valve being mounted to the support member.