Self-healing atrial defects are basically of the secondary foramen ovale type, and if the diameter of the defect is less than 8 mm, the age of self-healing is usually before the age of 3 years, and the probability of self-healing decreases between the ages of 3 and 5 years, whereas primary foramen ovale and venous sinus atrial defects are basically impossible to self-heal. In secondary foraminal atrial defects, if the diameter of the foramen ovale is less than 3 mm and the defect occurs after the infant is 3 months of age, the probability of spontaneous healing is very high within 1.5 years of age. If the diameter of the foramen ovale is 3-8 mm, the majority of the defects are likely to resolve spontaneously within one and a half years of age. If the diameter of the foramen magnum exceeds 8 mm, the probability of spontaneous healing decreases, and treatment should be aggressive as prescribed by the physician. Although there is a possibility that secondary foramen ovale defects can heal spontaneously, if the defects remain unclosed in a child older than 3 years, the child is susceptible to pneumonia and heart failure, which can be life-threatening in severe cases. Therefore, parents should bring their children to the hospital regularly for follow-up and receive appropriate treatment according to the doctor’s advice.