Intravascular trap and method of trapping particles in bodily fluids

A trap for trapping particulate material entrained in a fluid within a channel of a patient's body, comprising a guidewire having a distal segment, a resilient metal fabric and a cover;

• the metal fabric having a first end carried by the distal segment and a second end slidable along the guidewire, the metal fabric being disposed adjacent the outer surface of the guidewire when the second end is spaced proximally of the first end and extending generally outwardly of the guidewire when the second end is slid nearer the first end to define a generally dome-shaped particle-trapping screen which strains the particulate material from fluid passing therethrough, the second end being resiliently biased toward the first end to define the particle trapping screen when the fabric is not constrained;
• the cover being slidable along the guidewire from a first position spaced proximally of the screen toward a second position adjacent the screen, the cover in an expanded configuration defining a recess sized to receive a proximally-facing lip of the screen.

A retrieval system for retrieving particulate material entrained in a fluid within a channel of a patient's body, comprising:

• a) a flexible, elongate shaft adapted to follow a path within the channel;
• b) a medical device carried by the shaft at a distal location along the length of the shaft, the medical device having a collapsed configuration wherein it has a first, reduced diameter, and an expanded configuration wherein it has a second, enlarged diameter, the medical device in its expanded configuration limiting the flow of the particulate material within the channel distally beyond the medical device;
• c) a distally open cover slidable with respect to the shaft from a first position wherein it is spaced proximally of the medical device, thereby permitting the medical device to so limit the flow of the particulate material, to a second position wherein it engages the medical device to form therebetween an enclosure, the medical device and the cover together effectively limiting egress of the particulate material from the enclosure.