Improved embolism protection devices comprises fibers that can have one configuration for delivery of the device and a second configuration in which the device is deployed for filtering of flow within a vessel. In some embodiments, the fibers can be connected to a fiber support, which is connected to an actuating element. The actuating element controls the transition from the delivery configuration to the deployed configuration. The embolism protection device can comprise a guidewire. The fibers can be attached at one end to a fiber support structure and at another end to the guidewire. A hypotube can be attached to the proximal end of the fibers while the guidewire is attached at the distal end of the fibers with the guidewire extending within a central channel of the hypotube. The hypotube can be used to guide the delivery of treatment structures, such as a balloon and/or a stent.