There are many reasons for chest tightness and breathlessness, such as cardiac insufficiency, emphysema, asthma and other diseases, which are summarized below. 1. Cardiac insufficiency Coronary heart disease, cardiomyopathy and other diseases lead to a decline in the pumping function of the heart, reducing the effective circulation of blood, which can cause chest tightness and breathlessness. 2. Emphysema Emphysema can easily lead to ventilation or hyperventilation dysfunction, resulting in gas exchange disorders, which can cause chest tightness and breathlessness, especially when the symptoms are obvious during activities. 3. Asthma Due to bronchospasm will appear ventilation dysfunction, asthma is caused by airway hyperresponsiveness. When you have an attack, you will feel tightness in the chest and breathlessness. 4. Other diseases Heavy anemia, uremia and other systemic diseases, or anxiety and other psychological disorders, can also cause chest tightness and shortness of breath, need to be treated for the primary disease. In short, if you have chest tightness and breathlessness, you need to consult the hospital in time, and early diagnosis and treatment for the primary disease.