Tell me about tetralogy of fallot here?

Congenital heart dis: This is a congenital heart defect knows at "tetralogy" because the initial description discussed four findings: 1) ventricular septal defect, 2) overriding aorta, 3) pulmonary stenosis, 4) right ventricular hypertrophy. The cause is abnormal conotruncal septation, giving too much to the outflow to the aorta and not enough to the outflow to the lungs. This defect always requires surgical repair.