A heart that is larger than the normal cardiothoracic ratio is called cardiac hypertrophy, and the common causes of cardiac hypertrophy are cardiac outlet stenosis, increased peripheral vascular resistance, myocardial hypertrophy, increased blood flow and pressure, and decreased myocardial elasticity. 1. Cardiac outlet stenosis. Heart valve atresia and aortic valve stenosis can lead to narrowing of the heart’s outlets, which can lead to an increase in the size of the heart. 2. Increased peripheral vascular resistance. If you suffer from serious hypertension, it can also lead to increased peripheral vascular resistance, which is also a common cause of cardiac hypertrophy. 3. Myocardial hypertrophy. Patients suffering from cardiac hypertrophy may show signs of cardiac hypertrophy. 4. Increased blood flow and pressure, and decreased myocardial elasticity. If you suffer from hyperthyroidism, myocarditis, vitamin B1 deficiency patients, easy to cause the weakening of myocardial elasticity, as well as increased blood flow and pressure, which is also induced by cardiac hypertrophy of some important causes.