The present invention relates to a self-expanding device for sealing a defect in a wall, such as a septal defect. The device of the present invention has a helical shaped periphery formed from an elastic wire and at least one eyelet. The eyelet has a non-circular (“asymmetric”) shape which allows the eyelet to slide along a guiding mandrel. The non-circular shaped eyelet and mandrel prevent rotation of the eyelet relative to the mandrel thereby ensuring a consistent deployed shape. The present invention also incorporates a self-articulating catheter tip which can be bent to a variety of angles to enhance the ease of delivery. The tip is articulated by varying the position of the closure device within the articulated portion of the catheter.