US Patent 5,893,869
United States Patent and Trademark Office
University of Iowa Research Foundation (Iowa City, IA, US)
A percutaneous filter system for providing temporary filtering of emboli from the blood is disclosed, the filter system including a delivery catheter having a first working access lumen and a second filter deployment/retrieval lumen containing a filtering device which is deployable therefrom. The filtering device includes a deployment/retrieval wire section and a filtering element formed at the distal end of said deployment/retrieval wire section. The filtering element is made of shape memory/superelastic material and is formed to have a distally expanding frustoconical pre-disposed shape which, when the filtering element is deployed by being extended distally from the delivery catheter through the filter deployment/retrieval lumen thereof, defines a filtering channel that is offset from said deployment/retrieval axis and extends about the extended axis of the working access lumen of the delivery catheter. When the filtering element is so deployed within a blood vessel, emboli trapped within the filtering element are funneled toward working access lumen of the delivery catheter and can easily be aspirated or otherwise removed therethrough. With the filtering element in place in its deployed position, other instrumentation may also be passed through the working access lumen of the delivery catheter and the filtering channel to gain access into the blood vessel as desired.
Barnhart, William H. and Lang, Elvira V. Retrievable inferior vena cava filter system and method for use thereof. US Patent 5,893,869 filed February 19, 1997 and issued April 13, 1999. https://ir.uiowa.edu/patents/207