A system for aspiration includes an aspiration catheter including an elongate shaft including an aspiration lumen, and an open distal end, an extension tube, the lumen of the extension tube configured to be hydraulically coupled to the aspiration lumen, a peristaltic pump configured for driving fluid through the extension tube, a compressible portion disposed between the distal end and the proximal end of the extension tube, the compressible portion configured to be coupled to the peristaltic pump, such that operation of the peristaltic pump drives fluid from the aspiration lumen from the distal end of the extension tube to the proximal end of the extension tube, and a controller configured to receive a first signal from the first sensor and configured to vary the operation of the peristaltic pump based at least in part on a first signal received from a first sensor coupled to the aspiration lumen or extension tube related to a change in the characteristic of flow.