The squatting phenomenon is a special forced position, mostly seen in children with precocious tetralogy of Fallot. It appears as a special position of the child walking or playing with legs flexed and squatting for a moment, and then returning to normal walking, with squatting occurring repeatedly. So, what are the aspects to be examined? The following is the examination method of squatting phenomenon: 1, most cases appear cyanosis in the months after birth, severe cases show cyanosis after birth, shortness of breath after activity, children often feel weak, poor activity endurance, in strenuous activity, crying or early morning just wake up can have hypoxic attacks: children suddenly respiratory distress, cyanosis aggravated, serious cases can lead to convulsions, fainting, like squatting during activity is also one of the characteristics of the disease, squatting can increase Squatting can increase the resistance of body circulation, reduce the shunt of right heart blood to the aorta, thus increasing the blood volume of pulmonary circulation and improving the hypoxia; squatting can also reduce the lower body’s return blood volume, reduce the right-to-left shunt at the ventricular level, improve the oxygen content of body circulation and improve the cerebral hypoxia, a few cases can have epistaxis, hemoptysis, embolism or brain abscess and other symptoms. 2. Signs: The child has backward growth and development, cyanosis and pestle finger. There is a grade II-III systolic jet murmur on cardiac auscultation between the second and third ribs at the left edge of the sternum, and the loudness of the murmur is related to the degree of pulmonary artery orifice stenosis, the more severe the stenosis the lighter the murmur, and the second pulmonary artery sound is weakened, split or disappeared. Patients with squatting phenomenon must usually pay more attention to rest, more dietary fiber, eat more fruits, you can eat more apple juice, sugar cane juice, you can eat more back sweet and thick food, for the heart are very helpful.