If the ECG examination found the existence of left bundle branch conduction block, need to actively clarify the causes of left bundle branch conduction block, for the treatment of specific diseases, common diseases are coronary heart disease, hypertensive heart disease, heart failure, etc., as follows: 1, coronary heart disease: to actively improve myocardial ischemia, given to stabilize atherosclerotic plaques of medications, at the same time should be given to the long term antiplatelet aggregation of drugs to prevent thrombosis, but also to give long-term ACEI or ARB drugs to improve the prognosis of the patients. It is also necessary to give long-term ACEI or ARB drugs to improve the prognosis of patients.2, hypertensive heart disease: to give long-term, standardized blood pressure-lowering drugs, actively control the level of blood pressure, and give drugs to inhibit myocardial remodeling.3, heart failure: if heart failure occurs, the patient should actively control the heart failure.