Unitary body systems and devices and methods to use the same for retroperfusion. In an exemplary device embodiment of the present disclosure, the device comprises a unitary body having a wall and a lumen defined therethrough, a first portion terminating at a first end and configured for at least partial placement within a mammalian artery, a first one-way valve positioned at or near an end of the first portion opposite the first end, a second portion terminating at a second end and configured for at least partial placement within a mammalian vein, and a second one-way valve positioned at or near an end of the second portion opposite the second end.
