Transcatheter valve prosthesis having an external skirt for sealing and preventing paravalvular leakage

A heart valve prosthesis comprising:

• a stent having a compressed configuration for delivery within a vasculature and an expanded configuration when deployed at a target location, the stent including a plurality of crowns and a plurality of struts that define a plurality of openings, wherein endmost crowns and endmost openings are disposed about a circumference of an inflow end of the stent, each endmost crown being a curved segment extending between a pair of opposing struts;
• a prosthetic valve component disposed within and coupled to the stent, the prosthetic valve component being configured for deployment within a native heart valve;
• and
• a skirt coupled to and covering an outer circumferential surface of an inflow end of the stent, the skirt longitudinally extending over at least the endmost openings of the stent;
• and
• wherein when the stent is in the compressed configuration at least one endmost crown is configured to be positioned radially inwards with respect to a first endmost crown directly adjacent to and on a first side of the endmost crown positioned radially inwards and a second endmost crown directly adjacent to and on an opposing second side of the endmost crown positioned radially inwards, thereby forming a circumferentially-extending gap between the first endmost crown and the second endmost crown, the circumferentially-extending gap extending in a circumferential direction between the first endmost crown and the second endmost crown, wherein no portion of the endmost crown positioned radially inwards is disposed within the circumferentially-extending gap when the stent is in at least the compressed configuration, and
• wherein when the stent is in the expanded configuration the at least one endmost crown is positioned radially inwards with respect to the first endmost crown and the second endmost crown.