A prosthetic heart valve can include an outer support assembly, an inner valve assembly, which define between them an annular space, and a pocket closure that bounds the annular space to form a pocket in which thrombus can be formed and retained. Alternatively, or additionally, the outer support assembly and the inner valve assembly can be coupled at the ventricle ends of the outer support assembly and the inner valve assembly, with the outer support assembly being relatively more compliant in hoop compression in a central, annulus portion than at the ventricle end, so that the prosthetic valve can seat securely in the annulus while imposing minimal loads on the inner valve assembly that could degrade the performance of the valve leaflets.