Embolic protection device
An embolic protection device for use in a patient's blood vessel, such as the aorta, has an approximately cylindrical outer structure made of a filter mesh material and an approximately conical inner structure also made of a filter mesh material. On the downstream end of the embolic protection device, the wider end of the conical inner structure is joined to the cylindrical outer structure. The upstream end of the embolic protection device is open for blood to flow between the conical inner structure and the cylindrical outer structure. The space between the conical inner structure and the cylindrical outer structure defines a collection chamber for captured emboli. The narrow upstream end of the conical inner structure has a catheter port with a resilient seal that is sized for passage of a catheter shaft. The filter mesh material may be self-supporting or it may be supported on a resilient-framework or an inflatable framework.
1. An embolic protection device having an upstream end and a downstream end, said embolic protection device comprising:
a cylindrical outer sleeve comprising a filter mesh material; and
an inner structure comprising a filter mesh material and including a resilient seal having a plurality of flaps configured to form a sliding seal around a catheter shaft as the catheter shaft is introduced through a downstream end of the embolic protection device;
wherein a downstream end of the inner structure is attached to a downstream end of the cylindrical outer sleeve and the resilient seal of the inner structure is located at an upstream end of the inner structure; and
wherein emboli generated upstream of the embolic protection device flow into and are trapped within a collection chamber defined between the cylindrical outer structure and base of the inner structure.
2. The embolic protection device of claim 1 , wherein the cylindrical outer sleeve comprises a framework supporting the mesh.
3. The embolic protection device of claim 1 , wherein the plurality of flaps of the inner structure overlap.
4. The embolic protection device of claim 1 , further comprising a graspable structure attached to the downstream end of the embolic protection device.
5. The embolic protection device of claim 1 , wherein the device is coated with an anti-thrombogenic coating, such as heparin.
6. The embolic protection device of claim 2 , wherein the supporting framework comprises a self-expanding material.
7. The embolic protection device of claim 6 , wherein the self-expanding material comprises a shape-memory alloy.
8. The embolic protection device of claim 1 , wherein the mesh filter material has pore size in the range from 0.1 mm to 1 mm.
9. A method for advancing a catheter over an aortic arch, said method comprising:
providing an embolic protection device comprising a cylindrical outer sleeve including a filter mesh material and an inner structure including a filter mesh material and having a resilient seal comprising a plurality of flaps, wherein a wide base of the inner structure is attached to a downstream end of the cylindrical outer sleeve and the resilient seal of the inner structure is located at an upstream end of the cylindrical outer sleeve;
positioning the embolic protection device in the aorta and covering the aortic vessels with the upstream end of the cylindrical outer sleeve facing the heart; and
advancing the catheter from the downstream end of the embolic protection device through the resilient seal toward the heart;
wherein emboli generated upstream of the emboli protection device flow into and are trapped within a collection chamber defined at the downstream end of the embolic protection device between an inner surface of cylindrical outer structure and an outer surface of the inner structure.
10. The method as in claim 9 , wherein the cylindrical outer sleeve covers the aortic vessels.
11. The method as in claim 9 , wherein positioning comprises releasing the embolic protection device from a compressed condition so that the device self-expands within the aorta.
12. A method as in claim 11 , wherein the embolic protection device is self-supporting in its expanded configuration.
13. A method as in claim 7 , wherein the cylindrical outer structure and the inner structure comprise each comprise a framework supporting the filter mesh material.
14. A method as in claim 9 , further comprising retrieving the embolic protection device, wherein the embolic material remains trapped in the collection chamber during the retrieval.
15. A method as in claim 12 , wherein retrieving comprises retracting retraction members on the upstream and downstream ends of the emboli protection device to collapse the device.