A stent crimping assembly is provided for crimping a stent from a first diameter to a reduced second diameter. The crimping assembly includes a plurality of movable wedges disposed about a rotational axis to form a wedge assembly. Each wedge includes a respective first side and a second side converging to form a tip portion. The tip portions are arranged to collectively form an iris about the rotational axis thereof. The iris defining a crimp aperture about which the movable wedges are disposed. Each wedge is associated with a stationary structure and an rotational actuation unit such that during rotation of the actuation unit about the rotational axis, the iris is caused to rotate about the rotational axis, relative the stationary structure, for inward movement of the wedges to decrease the size of the aperture and outward movement of the wedges to increase the size of the aperture.