Cardiac angina attack may appear reflex arm pain, paroxysmal attack, containing nitroglycerin can be relieved. The typical symptom of angina pectoris attack is chest pain, but some patients can radiate to the left chest and left upper extremity, mostly manifested as paroxysmal swelling pain of the left upper extremity. Patients with angina can be relieved after taking nitroglycerin, and the symptoms of pain in the left arm will also be reduced. Some patients with angina, there may be no obvious chest pain symptoms, some patients alone for the left upper limb pain, can be accompanied by numbness sweating and other symptoms. When angina patients have left upper limb pain, they need to distinguish it from cervical spondylosis, frozen shoulder and other diseases, and if necessary, they should carry out electrocardiogram examination in time, and carry out diagnosis and treatment under the guidance of physicians to avoid delaying the condition.