Lying down with a feeling of pressure on the heart, considering coronary heart disease, heart failure or pleural effusion, etc., it is recommended that the patient go to the hospital in time to clarify the cause of the disease. 1. Coronary heart disease: coronary atherosclerotic heart disease, refers to atherosclerosis of the coronary arteries caused by narrowing or occlusion of the lumen, resulting in myocardial ischemia, hypoxia or necrosis of the common cardiovascular system diseases. When the patient lies down, the return blood volume increases, resulting in increased cardiac volume load, making people feel a sense of pressure on the heart. 2. Heart failure: It is a syndrome of circulatory dysfunction mainly caused by myocardial diastolic or systolic dysfunction due to insufficient cardiac output to maintain the metabolic needs of the tissues under the condition of moderate venous return. Etiologies include myocarditis, cardiomyopathy, and others. When the patient lies down, the return blood volume increases, causing the volume load of the heart to increase, resulting in a feeling of pressure on the heart. 3. Pleural effusion: Pleural effusion is a disease in which fluid retention in the pleural cavity occurs as a result of increased formation and decreased absorption of fluid in the pleural cavity. Pleural effusion can be caused by congestive heart failure, tuberculosis, liver cirrhosis, cancerous lymphatic obstruction and other diseases. Patients with pleural effusion may feel pressure on the heart when lying down. If you feel unwell, it is recommended to go to the hospital in time to avoid delay.