Methods and systems for attaching a radiopaque marker to a prosthetic heart valve to indicate a location of a commissure of the prosthetic heart valve are disclosed. As one example, a prosthetic heart valve can include a frame, a plurality of leaflets arranged within the frame, and at least one commissure comprising an attachment member comprising a central portion and a flap extending outward from the central portion, the flap folded over a radially outward facing side of the central portion, and the attachment member arranged across a selected cell of the frame. The commissure further comprises commissure tabs of two adjacent leaflets coupled to a radially inward facing side of the central portion, and a radiopaque marker arranged on the flap of the attachment member, between the flap and the radially outward facing side of the central portion.