Generally, there is a reason for the enlargement of the atria, but when there are no obvious symptoms, the heart function is in the compensatory period, and when the long-term enlargement of the atria causes the heart function to lose compensation, then obvious clinical symptoms will appear. The atria include the left atrium and the right atrium. Atrial enlargement does not occur when there is no underlying disease or congenital disease, but when it does occur, it is often caused by certain related diseases. If atrial enlargement is obvious, the physician can find that the apical beat is shifted to the lower left by visual examination, and the palpation shows obvious lifting beat, and the heart murmur boundary is enlarged to the lower left by percussion. The main causes of right atrial enlargement include pulmonary heart disease. Some diseases do not have obvious symptoms in the early stage, when the heart function is often in the compensatory period. Long-term untreated atrial enlargement can slowly lead to cardiac failure and symptoms such as chest tightness, shortness of breath and fatigue. When the discovery of atrial enlargement, it is recommended to consult a doctor in a timely manner, under the guidance of a professional physician to improve the relevant examinations to clarify the cause of the disease, early detection and early treatment, to avoid delays in the condition, resulting in adverse consequences.