Right heart catheterization: Catheter was inserted from peripheral vein and sent to superior vena cava, inferior vena cava, right atrium, right ventricle and pulmonary artery. In the process of intubation, we can observe the path of the catheter to determine whether there is an abnormal channel between the heart cavity and the great vessels, record the pressure curves of each part respectively, take blood samples from each part, measure their oxygen content, and calculate the cardiac output and hemodynamic indexes.
Left cardiac catheterization: send the catheter to pulmonary vein, left atrium, left ventricle and aorta, observe the route of the catheter, record the pressure curve of each part, take blood from each part, determine its oxygen content, and calculate the cardiac output and hemodynamic indexes. There are many methods of left heart catheter, such as using right heart catheter to enter pulmonary vein and left atrium through abnormal channel, or using right heart catheter to puncture atrial septum and enter left atrium. The commonly used method is retrograde intubation from peripheral arteries (such as femoral artery and brachial artery) and sent to aorta and left ventricle.