| 摘要 |
<p>An implantable medical device, such as a vena cava filter (10) has first and second ends (14, 16). At one end (14) there is provided a material capture element (18) which has a generally closed conical deployed shape and a narrow end disposed at or proximate the first end (14) of the device (10). The material capture element (18) includes a wide end (22) which faces the second end (16) of the device (10), the material capture element (18) having a zone (32) of wider radial dimension which provides a first vessel contact site of the device (10). A plurality of wire tethers (40) are coupled to the material capture element (18) at its wide end and extend to the second end (16) of the device (10). The wire tethers (44) define a substantially open passageway for blood and particulate material and are provided with portions (50) of wider radial dimension which provide a second vessel contact site of the device (10). The first and second contact sites (32, 50) are spaced from one another in the longitudinal dimension of the device, to provide orientational stability of the device within a vessel (12). A first retrieval element (26) is disposed at the first end of the device and coupled to the narrow end of the material capture element (18), while a second retrieval element (28) is disposed at the second end of the device and coupled to the wire tethers (40). The medical device (10) can, as a result, be retrieved from either end and can also be repositioned once having been deployed in a vessel (12).</p> |
