A thrombus retrieval device (10) includes a flexible catheter (12), a retrieval wire (26) fixed to the distal end (14) of the catheter (12) and which extends out of the catheter (12) at first and second apertures in the wall of the catheter (12). A trap element (28) typically made of a porous fabric material, is attached to the catheter (12) from the distal end (14) across the location of the apertures. The trigger wire (26) can be pulled in a proximal direction, which causes the catheter (12) to twist so as to form a loop. The trap element (28), attached to the catheter at location in which it loops, forms a net for trapping thrombi or other obstructions within a patients lumen.