Lutembacher's syndrome is a very rare form of congenital heart disease that affects one of the chambers of the heart (commonly the atria) as well as a valve (commonly the mitral valve). It is commonly known as both congenital atrial septal defect (ASD) and acquired mitral stenosis (MS). Congenital (at birth) atrial septal defect refers to a hole being in the septum or wall that separates the two atria; this condition is usually seen in fetuses and infants. Mitral stenosis refers to mitral valve leaflets (or valve flaps) sticking to each other making the opening for blood to pass from the atrium to the ventricles very small. With the valve being so small, blood has difficulty passing from the left atrium into the left ventricle. Septal defects that may occur with Lutembacher's syndrome include: Ostium primum atrial septal defect or ostium secundum which is more prevalent. Lutembacher's syndrome affects females more often than males. It can affect children or adults; the person can either be born with the disorder or develop it later in life. The syndrome was first described by René Lutembacher (1884–1968) of Paris in 1916. To correct Lutembacher's syndrome, surgery is often done. There are several types of surgeries depending on the cause of Lutembacher's syndrome (ASD Primum or ASD Ostium Secundum with Mitral Stenosis): Suturing (stitching) or placing a patch of tissue (similar to skin grafting) over the hole to completely close the opening Reconstructing of the mitral and tricuspid valve while patching any holes in the heart Device closure of ASD (e.g. Amplatzer umbrella or CardioSEAL to seal the hole) Percutaneous transcatheter therapy Transcatheter therapy of balloon valvuloplasty to correct MS Symptoms and signs As Lutembacher's syndrome is known for ASD and MS, most of the symptoms experienced will be associated with ASD and MS. For most people, they will remain asymptomatic (experience no symptoms) but when symptoms are shown, they are due mainly to ASD and will vary depending on the size of the hole in the atria. If the patient has a large ASD, pulmonary congestion (blood or fluid buildup in the lungs) will happen later but if the patient has a small ASD, symptoms will appear early in the disorder. In general, unless the ASD and mitral stenosis causing Lutembacher's syndrome is severe, symptoms may not appear until the second and third decade of the patient's life. As many of the patients