Aspiration thrombectomy supported by an oscillating metal probe within the catheter allows continuous aspiration of large thrombi without catheter obstruction. Thrombus aspiration assisted by an ultrasound-driven probe (frequency 26 kHz) and by an electric motor-driven probe (frequency 40 Hz) was compared in two different in vitro models: aspiration of large clots from a Petri dish and recanalization of thrombotic occlusions in a flow model. Comparable results were found for a 1 mm ultrasound-driven probe and a 0.5 mm motor-driven probe. The motor-driven device, however, seems to be more appealing for in vivo application because of its simplicity, probe flexibility, absence of thermal effects, and low cost.