Right ventricular hypertrophy is usually the cause of pulmonary hypertension, and over time it can line up as right ventricular hypertrophy which is a compensatory condition that requires treatment of the primary disease. Normally, the right ventricular wall is only 1/3 as thick as the left ventricular wall, so the combined left and right ventricular depolarization vectors point downward posteriorly to the left. In mild right ventricular hypertrophy, the left ventricular depolarization potential remains dominant and the change in the integrated ECG vector is not significant. Only when right ventricular hypertrophy is quite pronounced does it affect the direction of the integrated ECG vector more significantly (biased to the right anterior), causing characteristic changes, which is the reason why the ECG is not sensitive enough to diagnose early right ventricular hypertrophy. The etiology of right ventricular hypertrophy: Generally, right ventricular hypertrophy can be caused by increasing the systolic load of the right ventricle and the diastolic load of the right ventricle. There are three common causes: a. Pulmonary hypertension: 1. The most common acquired heart disease that can cause pulmonary hypertension, such as chronic pulmonary heart disease and rheumatic mitral stenosis. 2, left-to-right shunt class congenital heart disease late. 3, primary pulmonary artery disease pressure. Second, right ventricular high flow: such as tricuspid valve prolapse. 3, pulmonary artery orifice stenosis: such as tetralogy of Fallot, pulmonary valve stenosis. Right ventricular hypertrophy is a compensatory change in the heart. It is important to actively treat the primary disease to relieve the systolic or diastolic load of the right ventricle. Right ventricular hypertrophy can worsen and lead to right heart failure if the condition continues to worsen. Primary pulmonary hypertension Primary pulmonary hypertension is a rare disease that is distinguished from secondary pulmonary hypertension because its cause is unknown. Pulmonary heart disease in the elderly Chronic pulmonary heart disease is caused by chronic lesions of lung tissue, pulmonary artery vessels or thorax causing abnormalities in the structure and function of lung tissue, producing increased pulmonary vascular resistance and increased pulmonary artery pressure, causing dilatation and hypertrophy of the right heart, with or without right heart failure. Pediatric pulmonary hypertension The pressure in the pulmonary artery exceeds the highest normal value is called pulmonary hypertension, generally speaking, pulmonary artery systolic pressure is higher than 4kPa (30mmHg), the average pressure exceeds 2.7kPa (20mmHg) can be considered pulmonary hypertension.