Apparatus and methods for closing a septal defect including a flap of tissue partially detached from a septum of a heart. A needle is advanced through a patient's vasculature within a delivery apparatus until the needle is disposed within a first chamber adjacent the septum. The needle is directed through the flap of tissue until the needle is disposed within a second chamber opposite the septum. A filament attached to an intermediate region of the needle is pulled, thereby causing the needle to pivot about the intermediate region such that the ends of the needle straddle the septal opening. A locking element is secured to the filament to secure the flap of tissue against the septum, and the filament is cut. Alternatively, the filament is biased to coil to engage the flap of tissue and secure the needle against the septum to close the opening.