An aspiration system includes an elongate tubular member having a lumen; an aspiration catheter configured to be inserted through the lumen of the elongate tubular member, and including a tubular aspiration member having a proximal end, a distal end, and a lumen, and configured to at least partially extend out of the lumen of the elongate tubular member at the distal end of the elongate tubular member; an elongate support member coupled to the tubular aspiration member and extending between a proximal end of the aspiration catheter and the proximal end of the tubular aspiration member; and an annular sealing member coupled to the tubular aspiration member and configured to create a seal against an inner surface of the elongate tubular member, when a vacuum sufficient to cause aspiration is actively applied to the lumen of the elongate tubular member.