wing the device of FIGS. 6A-6C deployed in a channel of a patient's vascular system to occlude a Patent Ductus Arteriosus; [0020]FIGS. 9A and 9B are a side view and an end view, respectively, of a medical device in accordance with yet another embodiment of the invention; [0021]FIG. 10A is a side view of one molding element suitable for forming the invention of FIGS. 9A and 9B; [0022]FIG. 10B is a