Cobrahead malformation of the Amplatzer septal occluder device: an avoidable compilation of percutaneous ASD closure.

During deployment of an Amplatzer atrial septal occluder device to close a secundum ASD, the right atrial disk and waist of the device twisted, resulting in the cobrahead malformation. Postulated mechanisms for this complication include twisting of the device during loading into the delivery catheter and catching of leading edge of the device on the LA free wall or appendage, causing twisting during deployment. Retrieval of the device into the catheter and even removal of the device from the patient to allow manual untwisting may be required to allow the device to return to its original conformation for successful redeployment.