SELF-EXPANDING CARDIOVASCULAR OCCLUSION DEVICE

摘要

A self-expanding cardiovascular occlusion apparatus including a predetermined pattern of wire and three collinear bands, whereby pushing the bands together causes the two exposed braided or helical sections between them to flatten to two disk-like shapes. The disks are then forced outward relative to the middle band, causing the exposed braided or wound pattern to invaginate. The final shape is similar to two cones attached end to end. The device is heat treated to maintain this configuration. In use, the device is straightened to its cylindrical form, installed in the distal end of a device pusher which is advanced through a small diameter catheter installed in a blood vessel When the device is expelled from the device pusher, it returns to its expanded shape and lodges in a blood vessel, for example. Once lodged in the vessel, the device will initiate thrombus formation which will occlude the vessel. The final in-situ form of the device with cone-like ends has the ability to adapt to a range of vessel sizes. The wire loops formed when the braid or helical pattern is invaginated can move relative to one another. The result is that each end of the device can conform independently to the shape of the vessel. Since the device returns to the dual-cone shape, it will resist movement in either direction when placed in a vessel. The high number of wires exposed to blood flow help increase the rate of thrombosis and help center the device within the vessel lumen. The configuration of the device also ensures that it occupies a specific predictable length when placed in a vessel, which facilitates site specific embolization Although the primary use of the device is in embolotherapy to occlude a site in the vasculature, it may be used generally to close other sites in the cardiovascular system such as a septal defect. Methods of making and using the apparatus are also disclosed.