This is a case of infundibular pulmonary stenosis, which is a congenital heart defect with an obstruction to the right ventricular outflow tract at the subvalvular level. An isolated pulmonary stenosis occurs in 8 to 12% of all congenital heart defects. Pulmonary stenosis is often associated with many other congenital heart disease, such as tetralogy of Fallot and single ventricle. An isolated infundibular pulmonary stenosis is rare.