RESUMO
To date, no significant association has been reported between atrial septal defects (ASD) and cardiac myxomas. This study reports a 56-year-old woman with cardiac myxoma following transcatheter closure of ASD. She presented with a 3-month history of recurrent dizziness, vertigo, palpitations, and generalized weakness after undergoing ASD occlusion a year earlier. Echocardiography and cardiac computed tomography scans identified a large, mobile mass (7.2 cm × 2.8 cm) in the left atrium, protruding through the mitral valve. The patient underwent median sternotomy and pericardiotomy, and the histopathological examination confirmed the diagnosis of atrial myxoma. The current case illustrates the challenges in determining whether an atrial mass is a benign myxoma or a dangerous thrombus. While there is no definitive link between the implantation of an ASD closure device and the formation of a myxoma, the emergence of this tumor is a potential occurrence.