Lutembacher's syndrome is a rare cardiovascular defect comprising of mitral stenosis and atrial septal defect. A combination of acquired mitral stenosis and congenital atrial septal defect is the most well-recognized pattern. As atrial septal defect acts as a pressure relieving gateway, signs and symptoms of mitral stenosis may be attenuated and/or delayed in such patients. We have presented a case with Lutembacher's syndrome that was incidentally diagnosed as having such defect during outpatient check-up for upper respiratory infection.