Whether or not the foramen ovale is a serious illness should be determined by the size of the foramen ovale, the presence or absence of symptoms such as lack of oxygen to the brain and headaches. The foramen ovale usually closes about 1 year after birth, and if it does not close by the age of 3 years, it is called patent foramen ovale. When the foramen ovale is not closed, blood flow may go from the left atrium to the right atrium. When the aperture of the foramen ovale is small, the blood flow from the left side to the right side of the shunt is relatively small, usually does not have too much impact on the function of the heart, usually does not lead to lack of oxygen, headaches and other symptoms, this situation does not require special treatment, and does not need to take medication, only regular review. If the foramen ovale is large, or if the child is slow to grow and develop, or if there is cyanosis when crying, or if there are unexplained headaches, then prompt medical attention should be sought, and the patient may need to be treated with atrial septal defect occlusion, which may be beneficial to these patients. In the case of patent foramen ovale, further examination and, if necessary, surgical treatment can be performed in a regular hospital to avoid the effects of disturbed blood flow to the heart caused by patent foramen ovale.