Distal embolic protection devices with a variable thickness microguidewire and methods for their use

摘要

A distal embolic protection device for dedicated use in cerebral arterial blood vessels is described. The distal embolic protection device comprises a variable-thickness micro-guidewire and a collapsible filtering device mounted on the microguidewire over two mobile attachment points so that in its collapsed configuration, the thickness of the microguidewire and the filtering device at this region is less than or equal to 0.017 inch (0.432 mm) in thickness to be able to pass through existing conventional microcatheters. The mobile attachment points allow for rotatory and longitudinal mobility of the microguidewire while the filtering device is stable thereby decreasing the risk of trauma to the fragile cerebral arterial blood vessels. Preferably, the filtering device comprises an expansion assembly, e.g., a plurality of struts attached to a filter membrane that are in a folded position which self expand to the desired dimensions within the cerebral blood vessels. Also described are methods of using the distal embolic protection devices of this invention.

主权项

1. A distal embolic protection device for filtering thrombo-embolic material, debris or clots released during percutaneous neurovascular interventional procedures specifically performed in cerebral arterial blood vessels of a human, not attached to a balloon or a stent, and comprising:
a variable thickness microguidewire comprising a thinner segment bordered by thicker segments,
wherein said thinner segment is about 0.008 to 0.010 inch in thickness and has a length,wherein the thicker segments are no more than about 0.017 inch in thickness, a filtering device movable between an expanded configuration and a collapsed configuration, the filtering device configured to be deployed beyond an area of blockage or clot in a cerebral arterial blood vessel, the filtering device configured to be tracked uncovered through a microcatheter having an inner diameter of 0.017 inches from a proximal end of the microcatheter to a distal end of the microcatheter, the filtering device comprising:
an expansion assembly,a filter membrane, andtwo mobile attachment points, one of the mobile attachment points on each end of the filtering device, the mobile attachment points each having a length that covers a portion of the length of the thinner segment of the microguidewire, the lengths of the mobile attachment points together being less than the length of the thinner segment of the microguidewire, a first coil between one of the mobile attachment points and one of the thicker segments; a second coil between the other of the mobile attachment points and the other of the thicker segments; wherein the thinner segment of the microguidewire where the filtering device is mounted comprises a core microguidewire, and wherein each of the thicker segments of the microguidewire comprises the core microguidewire coated by a flexible hypotube, wherein the filtering device is rotatably mounted on the thinner segment of the variable thickness microguidewire between the thicker segments via the mobile attachment points, the filtering device rotationally and longitudinally displaceable relative to and independently of the microguidewire, wherein the thickness of the distal embolic protection device in the collapsed configuration measures no more than about 0.017 inch, wherein the length of the thinner segment of the variable thickness microguidewire is longer than a length of the filtering device in the collapsed configuration, wherein the filtering device is configured to float along the length of the thinner segment of the variable thickness microguidewire.