Expandable implant devices for filtering blood flow from atrial appendages

Abstract

Implant devices for filtering blood flowing through the ostium of an atrial appendage have component structures one or more of which are expandable. Devices with component structures in their unexpanded state have a compact size suitable for intra-cutaneous delivery to an atrial appendage situs. The expandable component structures are expanded in situ to deploy the devices. A device may have sufficiently short axial length so that most or almost all of the device length may fit within the ostium region. An expandable component structure in the device may include a blood-permeable filter element. The device may be deployed so that this component structure covers the ostium so as to direct the blood flow to pass through the filter element. The filter elements used in the devices may have hole size distributions selected to filter out harmful-size emboli. The filter elements may be embedded in elastic material so that hole-size distributions remain substantially unaffected by expansion of the device structures. Anchors attached to a component structure engage tissue surrounding the device and maintain the devices in position. The anchors may include inflatable anchors which engage interior walls of the atrial appendage.