Patent ID: 7942852

Claim:
A method for aspirating matter from the lumen of a blood vessel comprising: receiving an elongate catheter having proximal and distal ends and comprising: a first lumen extending from the proximal end of the catheter and having a chamber terminating in an open distal port at the distal end of the catheter; an elongate second lumen separate from the first lumen and extending from the catheter proximal end to a distal region of the catheter adjacent the catheter distal end; a side port in the distal region of the catheter communicating directly between the first and second lumens; and a valving mechanism disposed within the catheter distal region and operable within the catheter between open and closed configurations to selectively provide open or closed fluid communication through the side port between the chamber and the second lumen, the valving mechanism comprising a sealing member disposed within the first lumen and being slidable across the side port to selectively prevent or permit fluid flow between the chamber and the second lumen; while maintaining fluid communication closed between the chamber and the second lumen by the valving mechanism, applying negative pressure to a proximal end of the second lumen to accumulate a reservoir of vacuum within the second lumen; advancing the catheter intraluminally within the vessel to place the distal port immediately adjacent matter to be aspirated; and operating the valving mechanism to open communication between the chamber and the second lumen thus creating a sudden reduction in pressure within the chamber and at the distal port; whereby the sudden reduction of pressure within the chamber may cause the matter to be aspirated into the catheter through the distal port.