The causes of frequent feeling of chest tightness and breathlessness are as follows: 1. If patients often feel chest tightness accompanied by breathlessness, they should first consider respiratory diseases, such as chronic bronchitis, bronchiectasis asthma, chronic obstructive pulmonary disease, pulmonary hypertension, and even pulmonary heart disease, when there are symptoms of decreased blood oxygen saturation, high partial pressure of carbon dioxide, and decreased partial pressure of oxygen. 2. Cardiogenic diseases, such as coronary heart disease The symptoms of coronary artery insufficiency, stenosis, and spasm can cause ischemia and lack of oxygen in cardiac muscle cells, which can lead to chest tightness, shortness of breath, and dyspnea. 3, endocrine metabolic diseases, such as thyroid dysfunction and adrenocortical dysfunction, can also have this symptom. 4, cardiac neurosis Patients with cardiac neurosis will also have this clinical manifestation when they have plant nerve dysfunction.