A prosthetic device for a heart valve comprises a valve portion with prosthetic leaflets capable of reproducing the function of the valve leaflets of a native heart valve, expandable from a collapsed configuration for implantation to a working expanded configuration. The prosthetic device comprises also a containment portion which surrounds the valve portion to contain its expansion in the working expanded configuration. The prosthetic device comprises also a connecting portion which stably connects the valve portion to the containment portion through connecting elements. The containment portion has sub-components (61) with joint mechanisms which allow them to be deformed elastically in a straight configuration.
