Patent ID: 8647359

Claim:
A filter assembly for capturing debris within a blood vessel, comprising: an elongate shaft having a proximal end and a distal end; a filter disposed proximate the distal end of the elongate shaft, the filter including a filtering region and an attachment region, the filter having an expanded and a contracted shape; in the expanded shape, the filtering region a major opening defined adjacent the filtering region proximal end and consisting of a single layer of filter membrane defining a filter basket and extending between the major opening and the distal end of the filtering region, the filter membrane having a plurality of apertures defined therein that are configured to allow the passage of blood through the filtering region; the filter membrane further comprising a first generally linearly tapered portion and a second generally linearly tapered portion, the first generally linearly tapered portion defining a first included angle, and the second generally linearly tapered portion extending proximally from a proximal portion of the first tapered portion, the second generally linearly tapered portion defining a second included angle greater than the first included angle; and wherein the first generally linearly tapered portion extends at the first included angle for a length of the first generally linearly tapered portion and the second generally linearly tapered portion extends at the second included angle for a length of the second generally linearly tapered portion; wherein the filter assembly further comprises an expandable frame disposed within and supporting the first generally linearly tapered portion and the second generally linearly tapered portion.