A rare combination of a congenital heart defect and ostium secundum atrial septal defect with an acquired stenosis of the mitral valve. Although patients may be asymptomatic, electrocardiography contributes to early detection. Common signs and symptoms include fatigue, exertional dyspnea, heart murmur, and palpitations. Percutaneous transcatheter therapies have had successful outcomes in eligible patients. When severe coexisting conditions are present, such as congestive heart failure and pulmonary hypertension, outcomes may not be favorable.