A system can include a delivery catheter comprising a balloon and an implantable prosthetic heart valve. The prosthetic valve can have a plastically expandable and compressible unitary frame comprising first, second, and third rows of angled struts that define two circumferentially extending rows of diamond-shaped cells that extend continuously around the frame, and a valvular structure comprising a plurality of leaflets. A cusp edge portion of each leaflet is connected to the frame by a skirt that is connected to and disposed between the frame and the cusp edge portions of the leaflets, the skirt being connected to consecutive struts in the first, second, and third rows of struts with sutures. The compressed prosthetic heart valve can be mounted around the balloon and radially expanded to the expanded configuration with the balloon inside a patient's body.