Whether vague left precordial pain can cause sudden death depends on the disease suffered. Vague pain in the left precordial region is most often seen in heart disease and pleural cavity disease. Pleural cavity disease does not usually cause sudden death, and heart disease has a higher risk of causing sudden death. In case of heart disease causing vague pain in the left precordial region, such as coronary artery disease, caused by insufficient blood supply to the heart, it may cause sudden death in severe cases. Therefore, patients with coronary artery disease or those with risk factors for coronary artery disease should pay attention and get timely treatment to prevent sudden death if they have unexplained fatigue and weakness with chest tightness, edema, syncope, frequent panic attacks with gradual worsening of symptoms and even blackness in front of the eyes and weakness of limbs. In addition, pleural cavity diseases such as pleurisy, pneumothorax, pleural effusion and costochondritis, as well as emotional and neurological factors, can also cause vague pain in the left precordial region, but the incidence of sudden death is low. It is suggested that if patients feel vague pain in the left precordial area, they should go to the cardiology department of the hospital as soon as possible to have an electrocardiogram and echocardiogram done to clarify the diagnosis and provide symptomatic treatment.