It refers to combination of congenital atrial septal defect with acquired mitral stenosis. Recibido 9 abril 2010, aceptado 26 mayo 2010 rev chil cardiol 2010. Typically, the lefttoright shunt is an atrial septal defect asd of the ostium secundum variety. Lutembachers syndrome is a very rare form of congenital heart disease that affects one of the. Here, we will discuss a case of a pregnant lady who developed breathlessness during her third trimester of pregnancy and on detailed examination and investigation, she was found to be having lutembacher s syndrome. It is commonly known as both congenital atrial septal defect asd and acquired mitral stenosis ms. Lutembacher syndrome is defined as a combination of mitral stenosis and a left toright shunt at the atrial level. Lutembachers syndrome is the combination of mitral valve stenosis and a secundumtype atrial septal defect. Lutembacher syndrome is defined as a combination of mitral stenosis and a lefttoright shunt at the atrial level.