The present invention relates to a medical device and method of forming the medical device. In particular, the present invention relates to a medical device having a tubular membrane structure over a radially expandable structural frame, and to a method of forming the tubular membrane on the radially expandable structural frame. In one aspect, a structural frame is placed over a spinning mandrel and a fiber is electro-statically spun over at least a portion of the structural frame forming a membrane. A transfer sheath may be used between the mandrel and structural frame to prevent the electro-statically spun fiber from adhering to the mandrel. In another aspect, a first membrane is spun over the mandrel before the structural frame is placed over the mandrel. In this aspect, at least a portion of the structural frame is sandwiched between the membranes. The membrane or membranes and structural frame form a fiber spun frame assembly. The fiber spun frame assembly may be coated with an elastic polymer. In addition, the membrane or membranes may go through some post processing to achieve desired characteristics or configurations.