Multi-purpose valve

Claim 1

A multi-purpose valve ( 5 ) for use as a therapeutic device, comprising a band ( 1 ) having when in situ the shape of a conical spiral formed by multiple, successive, helical turns, in such a way that at a first pressure difference across the valve, the helical turns of the band abut one another and seal the cone, whereas at a second pressure difference across the valve, which is larger in the direction towards the tip of the conical spiral than the first pressure difference, the valve is extended axially such that said turns separate from another so as to allow flow therebetween, characterised in that he valve is constituted by one single band ( 1 ) of a thermodynamic metal alloy with shape memory, with said conical shape as a memorised shape, and with transition temperature in the range for the normal body temperature of a mammal, with the result that the band has a linear shape below the transition temperature and assumes the memorised, conical shape above the transition temperature, making the valve percutaneously implantable.