Angioplasty device with embolic filter
An angioplasty device has a filter associated with it to capture embolic particles that may be broken free during an angioplasty procedure. In one embodiment the embolic filter has a frame in which struts are connected to end rings and to each other by a plurality of interconnected oval members. In another embodiment the device includes an actuator at the proximal end of an actuator wire. By rotating a knob on the device, the physician can smoothly tension the wire by a predetermined amount to prevent the filter from opening too much or too little. Various other embodiments of filter frames are also disclosed.
1. A percutaneous transluminal angioplasty device, comprising an elongated catheter having proximal and distal ends and an outer side wall;
a treatment means attached to the catheter adjacent to the distal end thereof for treating a stenosis in a vessel;
a frame supporting an embolic filter, the frame being attached to the catheter between the treatment means and the distal end of the catheter, the frame being collapsible for insertion into a blood vessel, and the frame being expandable to an expanded position to deploy the embolic filter to capture emboli related into a bloodstream by operation of the treatment means, comprising:
a proximal ring;
a distal ring;
a plurality of longitudinally extending struts, each strut having a longitudinal axis and a width measured transverse to the longitudinal axis, wherein each strut of the plurality of struts comprises:
a proximal end attached to the proximal ring;
a distal end attached to the distal ring;
a midsection;
first, second, and third zones of weakness, each zone of weakness comprising:
a set of oval shaped members spaced along the longitudinal axis of the strut, formed in the strut, and circumscribing an oval opening, the oval opening having a long axis that is substantially transverse to the longitudinal axis of the strut; and
at least one connecting link formed in the strut and extending between adjacent oval shaped members of the zone of weakness, wherein each connecting link has a width, and the width of each connecting link is less than the width of the strut in which it is formed,
wherein the oval members of the first zone of weakness are formed in the strut adjacent the proximal end of the strut,
wherein the oval members of the second zone of weakness are formed in the strut adjacent the distal end of the strut,
wherein the oval members of the third zone of weakness are formed in the midsection of the strut, and
wherein each oval shaped member of the first, second, and third zones of weakness corresponds to a flex point that permits radial movement of its associated strut while restricting lateral movement of its associated strut,
wherein each oval shaped member is configured for longitudinal elongation to permit expansion of the frame, and
wherein the frame further comprises at least one expandable and resilient radial connector, each radial connector radially connecting two adjacent struts by attaching at a point along the third zone of weakness.
2. The percutaneous transluminal angioplasty device of claim 1 , wherein the treatment means comprises an angioplasty balloon.
3. The percutaneous transluminal angioplasty device of claim 1 , wherein the treatment means comprises a stent.
4. The percutaneous transluminal angioplasty device of claim 1 , wherein the treatment means comprises a mechanical thrombectomy device.
5. The percutaneous transluminal angioplasty device of claim 1 , wherein each of the plurality of struts are formed from a shape-memory material that urges the struts into a collapsed position.
6. The percutaneous transluminal angioplasty device of claim 5 , wherein the shape-memory material comprises nitinol.
7. The percutaneous transluminal angioplasty device of claim 5 , further comprising an actuator wire extending through the catheter and having proximal and distal ends, wherein the distal end of the actuator wire exits the distal end of the catheter and attaches to one of the proximal or distal rings, wherein the one of the proximal or distal rings attached to the distal end of the actuator wire is a movable ring and the one of the proximal or distal rings not attached to distal end of the actuator wire is a fixed ring, and wherein when the frame is in the collapsed position, pulling on the proximal end of the actuator wire moves the movable ring toward the fixed ring, and wherein movement of the movable ring toward the fixed ring causes the plurality of struts to expand radially outward, thereby expanding the frame to the expanded position.
8. The percutaneous transluminal angioplasty device of claim 7 , wherein, when the frame is in the expanded position, releasing the proximal end of the actuator wire permits the shape-memory material of the struts to return the struts to their normal, collapsed position, collapsing the frame.
9. The percutaneous transluminal angioplasty device of claim 7 , wherein the catheter further comprises an aperture in an outer side wall located between the movable ring and the fixed ring, wherein the distal end of the actuator wire exits the catheter through the aperture.
10. The percutaneous transluminal angioplasty device of claim 1 , wherein each radial connector attaches two adjacent struts by extending between a connecting link of the third zone of weakness of each of the two adjacent struts.
11. The percutaneous transluminal angioplasty device of claim 10 , wherein each strut of the plurality of struts is predisposed to bend radially outwardly at a bending point, wherein the bending point comprises a selected oval member of the third zone of weakness of each strut, wherein the selected oval member is positioned between the distal ring and connecting link at which a radial connector is connected to the strut.
12. The percutaneous transluminal angioplasty device of claim 1 , wherein each radial connector comprises two legs and an arcuate head portion, each leg having a first end connected to one of the adjacent struts and a second end connected to an arcuate head portion.
13. The percutaneous transluminal angioplasty device of claim 12 , wherein the arcuate head portion of each radial connector circumscribes an arc of greater than 180°.
14. The percutaneous transluminal angioplasty device of claim 12 , wherein each radial connector is configured for radial expansion about and between a closed position and an open position, and wherein, when the plurality of radial connectors are positioned in the open position, the plurality of radial connectors cooperate to form a sinusoidal ring.
15. The percutaneous transluminal angioplasty device of claim 1 , wherein a filter mesh overlies a distal portion of the struts, and wherein, in the expanded position, the struts expand radially outward, radially expanding the filter mesh.
16. The percutaneous transluminal angioplasty device of claim 15 , wherein each strut of the plurality of struts is predisposed to bend radially outwardly at a bending point, wherein the bending point comprises a selected oval member of the third zone of weakness of each strut, wherein the selected oval member is positioned between the distal ring and a point at which a radial connector is connected to the strut, and wherein a proximal edge of the filter mesh is attached to the plurality of radial connectors.