An expandable, bistable open cell design incorporates the following features: a first relatively stiff portion (152) having first and second ends and a first relatively flexible portion (154) connected to the first and second ends of the first relatively stiff portion, the first relatively stiff portion and the first relatively flexible portion substantially surrounding a first open area (156) of the stent structure; a second relatively stiff portion (158) having first and second ends and a second relatively flexible portion (160) connected to the first and second ends of the first relatively stiff portion, the first relatively stiff portion and the first relatively flexible portion substantially surrounding a second open area (162) of the stent structure; and an opening (110) formed through the first relatively stiff portion and the second relatively flexible portion such that the opening connects the first and second open areas, thereby creating first and second intermediate ends (152a, 152b) of the first relatively stiff portion and first and second intermediate ends (160a, 160b) of the second relatively flexible portion. The first intermediate end (152a) of the relatively stiff portion is connected to the first intermediate end (160a) of the relatively flexible portion so as to create a first inward apex (170), the second intermediate end (152b) of the relatively stiff portion is connected to the second intermediate end (160b) of the relatively flexible portion so as to create a second inward apex (172), and the stent structure is configured such that, in a collapsed configuration, the first inward apex (170) is in contact with the second inward apex (172) and, in an expanded configuration, the first inward apex is biased to move in a first circumferential direction and the second inward apex is biased to move in a second circumferential direction that is different than the first circumferential direction.