Plugging the gaps

An implant that permanently seals holes in the heart has been developed by
Peter Block and his colleagues at Emory University in Atlanta. The device has
two collapsible polyester patches attached to the ends of a small metal
rod—like a double-ended umbrella. When collapsed, the implant can be
threaded through a vein in the leg and into the heart. One of the patches plugs
the hole and the other rests against nearby tissue to anchor the implant. The
procedure takes half an hour, says Block, and tissue grows into the polyester
patches within a month.