EMBOLIC PROTECTION DEVICE
An embolic protection device has a collapsible filter element ( 105 ) mounted on a carrier such as a guidewire ( 101 ). The filter element ( 105 ) collapses into the outer end of a catheter ( 118 ) for deployment and retrieval through a vascular system of a patient. The filter element ( 105 ) has a collapsible filter body with a proximal inlet end and a distal outlet end. The proximal inlet end has inlet openings sized to allow blood and embolic material enter the filter body. The outlet end has outlet openings which allow through passage of blood but retain embolic material within the filter body. After use, the catheter ( 118 ) is movable alone the guidewire ( 101 ) to engage the proximal end of the filter element and close the inlet openings before sliding over the filter element from the proximal end to the distal end to progressively collapse the filter body on the guidewire ( 101 ) for retrieval. The filter element ( 105 ) may conveniently be mounted on a tubular sleeve ( 104 ) which is slidable and rotatable on the guidewire ( 101 ) between spaced-apart stops ( 106, 120 ) on the guide wire ( 101 ) which allows some manipulation of the guidewire independently of the filter when the filter is in use.
1 . An embolic protection device, comprising:
a support element for delivery through a vascular system of a patient; and
a foam filter element associated with the support element, the foam filter element being movable between a collapsed stored position for movement through the vascular system, and an expanded position for occluding a blood vessel such that blood passing through the blood vessel is delivered through the foam filter element but embolic material in the blood is retained in the foam filter element.
2 . The embolic protection device of claim 1 , wherein the support element is a guidewire.
3 . The embolic protection device of claim 2 , wherein the guidewire is a hollow guidewire.
4 . The embolic protection device of claim 3 , wherein the hollow guidewire comprises a polymeric or metallic tube.
5 . The embolic protection device of claim 3 , wherein the hollow guidewire comprises a spring.
6 . The embolic protection device of claim 3 , wherein the filter element is overmoulded onto or joined to the hollow guidewire.
7 . The embolic protection device of claim 1 , wherein the foam filter element is flexible and is capable of engaging with a wall of the blood vessel.
8 . The embolic protection device of claim 7 , wherein the foam filter element is capable of engaging with the wall of the blood vessel along a length of a periphery of the foam filter element.
9 . The embolic protection device of claim 1 , wherein the foam filter element comprises a compressible, porous polymeric foam.
10 . The embolic protection device of claim 9 , wherein the compressible, porous polymeric foam has a open cell structure with a density less than 400 kg per cubic meter.
11 . The embolic protection device of claim 10 , wherein the compressible, porous polymeric foam has a open cell structure with a density less than 100 kg per cubic meter.
12 . The embolic protection device of claim 11 , wherein the compressible, porous polymeric foam has a open cell structure with a density less than 50 kg per cubic meter.
13 . The embolic protection device of claim 1 , wherein the filter element further comprises at least one pathway through the filter element for allowing blood cells and other blood constituents to pass therethrough but for capturing emboli of a size greater than a pore size.
14 . The embolic protection device of claim 1 , wherein the filter element has a proximal inlet and a distal outlet, the proximal inlet having a plurality of inlet openings sized to allow blood and embolic material to enter the filter element, and the distal outlet having openings sized to allow through passage of blood but to retain embolic material within the filter.
15 . An embolic protection system, comprising:
an embolic protection device for delivery through a vascular system of a patient, comprising a support element and a foam filter element associated with the support element, the foam filter element being movable between a collapsed stored position for movement through the vascular system, and an expanded position for occluding a blood vessel such that blood passing through the blood vessel is delivered through the foam filter element but material in the blood is retained in the foam filter element; and
a catheter, comprising a housing or pod, wherein the housing or pod maintains the filter element in the collapsed stored position.
16 . The embolic protection system of claim 15 , wherein the filter element moves to the expanded position when the housing or pod is withdrawn from the blood vessel.
17 . A method for providing embolic protection, comprising:
delivering an embolic protection device through a vascular system of a patient, the embolic protection device comprising a support element and a foam filter element associated with the support element, the filter element being movable between a collapsed stored position for movement through the vascular system, and an expanded position for occluding a blood vessel such that blood passing through the blood vessel is delivered through the filter element but material in the blood is retained in the foam filter element; and
engaging the foam filter element with a wall of the blood vessel.
18 . The method for providing embolic protection of claim 17 , wherein the engaging of the foam filter element with a wall of the blood vessel comprises engaging the foam filter element with the wall of the blood vessel along a length of a periphery of the foam filter element.