In male patients, vague pain in the left chest is caused by the following conditions: first, myocardial ischemia. Especially if the patient has a history of hypertension or diabetes mellitus and atherosclerosis, the patient may have coronary artery spasm or stenosis after a long period of time, and may have vague pain in the precordial region or induced after exertion. Normally, we should pay attention to low-salt and low-fat diet, and apply drugs for secondary prevention of coronary heart disease. Secondly, some patients with pleural thickening or pulmonary fibrosis and pulmonary nodular disease left after lung tissue infection may also show vague chest pain, which may be aggravated after activity and even accompanied by cough and sputum, and chest CT examination can also make a clear diagnosis. Patients with pulmonary fibrosis or pulmonary nodular disease may also have vague chest pain, which may worsen after activity and may even be accompanied by coughing and coughing.