Tetralogy of Fallot
Overview
Plain-Language Overview
Tetralogy of Fallot is a congenital heart defect that affects the heart's structure and function. It involves four key abnormalities that disrupt normal blood flow through the heart and lungs. This condition primarily impacts the cardiovascular system, leading to reduced oxygen levels in the blood. Children with this defect often experience cyanosis, which is a bluish tint to the skin due to low oxygen. The heart has to work harder to pump blood, which can cause shortness of breath and fatigue. Early diagnosis and management are important to address these symptoms and improve quality of life.
Clinical Definition
Tetralogy of Fallot is a congenital cardiac malformation characterized by four anatomical defects: ventricular septal defect (VSD), pulmonary stenosis, overriding aorta, and right ventricular hypertrophy. The primary pathophysiology involves obstruction of right ventricular outflow due to pulmonary stenosis, causing right-to-left shunting of deoxygenated blood through the VSD into the systemic circulation. This results in hypoxemia and cyanosis. The condition is usually caused by abnormal development of the infundibular septum during embryogenesis. Clinically, it presents with cyanotic spells, clubbing, and a characteristic harsh systolic murmur. It is a major cause of cyanotic congenital heart disease in infants and children and requires surgical correction for definitive management.