A positive cardiac foam test is not normal, indicating that the patient may have a patent foramen ovale or atrial septal defect. 1. Unenclosed foramen ovale: It is a congenital anomaly of the heart structure, and it can be positive in cardiac foaming test when it is examined by a doctor. Usually, patients with patent foramen ovale are asymptomatic, but when the pressure of the right atrium exceeds that of the left atrium, it will easily lead to obvious right-to-left abnormal shunting of blood flow in the heart, which can be manifested as unexplained headache, dizziness, dyspnea, limb weakness and so on. 2. Atrial septal defect: also belongs to a congenital heart developmental defect, the cause is not clear, and the cardiac foam test can be positive. There may be no obvious signs in childhood, but in adulthood, it is easy to be accompanied by weakness, palpitation (rapid heartbeat, often accompanied by panic), shortness of breath, swelling of limbs and other symptoms. In addition to a positive cardiac foam test, X-ray examination shows enlargement of the right atrium and right ventricle, color Doppler echocardiography shows horizontal wind flow in the atria and two-dimensional echocardiography shows atrial septal echogenicity loss, and overloading of the right heart. It is recommended that those with positive cardiac foam test should undergo further detailed examination in order to clarify the cause of the disease and then follow the doctor’s instructions to prevent further aggravation of the disease.