A prosthetic device for use in an anatomical orifice or lumen of a patient includes an expandable first stent structure coupled to a valve support structure having at least one leaflet. The stent structure includes a collar provided with at least one groove or opening adapted to engage a tab extending from the valve support structure. Rotation of the stent structure and valve support structure relative to one another assembles the prosthetic valve device. The prosthetic valve device may be used for sutureless treatment of various valvular conditions such as aorta stenosis and mitral valve replacement.