Left chest pain may be caused by angina pectoris, cystic hyperplasia of the breast, neurosis and intercostal neuritis. 1. Angina pectoris: angina pectoris may lead to the symptom of left chest paresthesia, which usually lasts for only 3 to 5 minutes, and may occur once a day or several times a day, and is often relieved after rest. 2. Cystic hyperplasia of the breast: cystic hyperplasia of the breast occurs in women of childbearing age, these patients may also have symptoms of left chest pain, the patient may also have symptoms of unilateral breast swelling and pain and lumps, these symptoms are often related to the menstrual cycle, before menstruation is obvious, after menstruation to reduce. 3. Neurosis: patients with neurosis may also have symptoms of left chest pain, in addition, patients may also have sleep disorders, dizziness, headache and other symptoms. 4. Intercostal neuritis: intercostal neuritis can also lead to left chest numbness and pain, mainly neuroinflammation, in the onset of the attack can be manifested as pins and needles pain, along the ribs in the direction of the direction of the strip area radiated, can be caused by the cold, fatigue and so on. In addition to the above diseases, other diseases can also lead to the symptoms of left chest pain, if this symptom persists unrelieved, should consult a doctor in time, ask the doctor to deal with.