Left atrial occlusion devices and methods of implantation. The left atrial occlusion devices can have a plurality of flexible elongate members forming a distally open cage configuration when expanded. The distal ends of the elongate members can optionally be atraumatic. Also disclosed is a method of occluding a left atrial appendage that includes expanding an expandable member against the left atrial appendage to seal off the left atrial appendage from blood flow from the left atrium, and determining if blood is flowing from within the left atrial appendage to a location outside the left atrial appendage.