Abstract: A system is provided that includes N populated frame assemblies (PFAs) having a folded nested state and an unfolded state. The N PFAs have a nesting height when in the folded nested state that is less than a sum of a height of all PFAs of the N PFAs, where the N is a non-zero integer number greater than one. The embodiments also include a frame assembly and a method of manufacture.

Abstract: Disclosed herein is an expandable sheath that can be used in conjunction with a catheter assembly to introduce a prosthetic device, such as a heart valve, into a patient. The disclosed herein sheath can minimize trauma to the vessel by allowing for temporary expansion of a portion of the introducer sheath to accommodate the delivery apparatus, followed by a return to the original diameter once the prosthetic device passes through. Some aspects can include a sheath comprising an inner layer comprising a reinforcing layer comprising a plurality of struts that can be encapsulated within a polymer layer comprising a tether portion and an outer layer disposed over the inner layer. The disclosed sheath is configured to locally expand from a predetermined first diameter d1 to an expanded second diameter d2 during application of a radial outward force by passage of a medical device through the sheath.