The disease was first described in its entirety by French internist Etienne Fallot in 1988, hence the name Tetralogy of Fallot. The first successful reduction surgery was performed by Dr. Alfred Blalock at Johns Hopkins University in 1945, and the first intracardiac repair was performed by Dr. Lillehei at the University of Minnesota in 1954. The “quadruplets” that make up the criteria for tetralogy of Fallot are: ventricular septal defect, right ventricular outflow tract obstruction, aortic span, and right ventricular hypertrophy. These “four malformations” are all caused by a basic morphologic abnormality. –The septal defect is nonrestrictive because it results from the forward and rightward displacement of the funnel or cone of the heart and the septum, that is, from the malalignment of the upper and lower ventricles during the embryogenesis of the heart. The septal hypoplasia and the forward and leftward displacement of the septum eventually lead to right ventricular outflow tract obstruction. Rightward shift of the aortic root results in aortic straddling. The common comorbid malformations in Tetralogy of Fallot are atrial septal defect, patent ductus arteriosus, complete atrial septal defect and multiple ventricular septal defects, left superior vena cava malformation, anomalous origin of the left anterior coronary artery, and anomalous origin of the right and left pulmonary arteries. The symptoms of tetralogy of Fallot are determined by the degree of right ventricular outflow tract obstruction. At birth, the degree of cyanosis is mild in the pediatric population. However, the hypertrophy of the right ventricular funnel progressively increases with age, thus increasing the degree of cyanosis in children during the period from 6 months to 12 months of life, even leading to episodes of hypoxia. A small percentage of children present with severe cyanosis at birth or shortly after birth, and in such cases their outflow tract obstruction is mainly due to hypoplasia of the pulmonary valve annulus. In cases of tetralogy of Fallot with pulmonary valve or pulmonary trunk atresia, pulmonary artery flow is primarily dependent on the PDA and multiple collateral main pulmonary arteries (MAPCAs). Untreated older cases of tetralogy of Fallot can lead to pestle and mortar fingers, shortness of breath, poor exercise tolerance, brain abscess, cerebral embolism, pulmonary embolism, and erythrocytosis because of prolonged cyanosis. MAPCAs can cause congestive heart failure. The main signs of tetralogy of Fallot are cyanosis, cardiac signs: normal S1, single S2, and right ventricular outflow tract obstruction causing a characteristic systolic murmur that disappears during episodes of hypoxia. In the presence of larger and more numerous MAPCAs, a continuous murmur can be heard in the dorsal and bilateral lung fields. The pestle finger develops gradually from 6 months after birth. It may disappear after radical surgery. The combination of a hypertrophied right ventricle with an upward-pointing apex and a narrowed pulmonary artery trunk with a depressed left upper edge of the heart shows the characteristic “bootstrapped heart” on an orthogonal radiograph. The main purpose of cardiovascular imaging in tetralogy of Fallot is to provide information for surgical procedures. Cardiac catheterization can be performed if the anatomy of the pulmonary artery is needed, if the echocardiogram does not show the coronary arteries, or if multiple ventricular septal defects are suspected. Cardiac catheterization provides a better picture of the type and extent of right ventricular outflow tract stenosis. Aortography can accurately demonstrate the collateral arteries of the main pulmonary artery, and cephalic obliquity shows stenosis of the right and left pulmonary artery branches. Hemodynamic parameters are of little significance and should not stimulate the right ventricular outflow tract to avoid hypoxic episodes. Hypoxic episodes are most often seen in infancy and often occur during feeding and crying. The child presents with a sudden increase in cyanosis, dyspnea, fast and then slow frequency, bradycardia, reduced or absent heart murmurs, and in severe cases, convulsions, coma and even death. The hypoxic attack must be treated urgently, including knee-chest position, oxygenation, sedation, sodium bicarbonate supplementation, release of right ventricular outflow tract spasm (morphine 0.1 mg/kg/dose, intravenous injection, or propranolol 0.05-0.1 mg/kg/dose, intravenous drip), and elevation of body circulation blood pressure (phenylephrine 0.05-0.1 mg/kg/dose, intravenous drip). Most children with tetralogy of Fallot are born with insignificant cyanosis and do not require treatment. Surgical intervention is necessary if arterial oxygen saturation is reduced to 75% to 80%, and episodes of hypoxia are usually considered to be an indication for surgery. In the absence of these special circumstances, most medical centers consider the age of 1 to 2 years to be the time period for elective radical surgery. If cardiovascular imaging shows that the sum of the diameters of the pulmonary arteries before the first branch vessel from the right and left pulmonary arteries divided by the diameter of the descending aorta at the level of the transverse septum is greater than 1.2 to 1.3, radical surgery is safe. Otherwise, it is best to perform a second-stage surgery. Most experts believe that it is best to perform early complete radical surgery, which has the advantages of normal organ growth and development, elimination of hypoxia, not over resecting the right ventricular muscle bundle, better distant left ventricular function, and a reduced incidence of arrhythmias in the distant future. The current surgical mortality rate for tetralogy of Fallot is only 5% in some cardiovascular centers. The outcome of surgery for tetralogy of Fallot is determined by the diameter of the pulmonary artery and the presence or absence of stenosis in the surrounding pulmonary arteries, anatomic abnormalities in the coronary arteries, and the presence or absence of multiple ventricular septal defects, which can have serious consequences in the event of a missed diagnosis. Therefore, preoperative cardiovascular angiography is necessary.