The main causes of sudden cardiac death include ischemic heart disease, hypertension combined with left ventricular hypertrophy, and other cardiovascular diseases. 1. Ischemic heart disease accounts for about three quarters of all sudden deaths, and most patients are over 30 years old and have a history of coronary heart disease, such as myocardial infarction. 2. Hypertension combined with left ventricular hypertrophy is another major cause of sudden death. This kind of patients with long-term hypertension secondary to myocardial injury can easily lead to heart failure, and patients with heart failure have a greater chance of sudden death. 3. Other cardiovascular diseases, such as non-atherosclerotic coronary artery anomalies, hypertrophic cardiomyopathy, sick sinus node syndrome, and aortic coarctation may lead to sudden cardiac death.