A heart valve prosthesis (1), including: a stent framework (2), which can be transferred from a collapsed state into an expanded state, in which the stent framework (2) extends along an axis (A′), wherein the stent framework (2) has a plurality of struts (20, 24), which form a plurality of cells (21a, 21b, 25) connected to one another; and a heart valve (3), which is fixed to the stent framework (2). In accordance with the invention, the thickness (d′) of the struts varies in the peripheral direction (U) of the expanded stent framework (2).