In addition to the clinical presentation, a number of tests are pivotal in the assessment of pulmonary hypertension. These include: 1. Transcutaneous oxygen saturation (SpO2) or arterial oxygen saturation (SaO2): As PAH progresses, pulmonary blood decreases significantly and so does the oxygen intake. Oximetry provides a visual representation of the amount of oxygen in the blood and is easy to measure. Generally speaking, patients with blood oxygen saturation over 95% can mostly receive corrective surgery for preeclampsia; if it is below 90% or even below 85%, the chance of surgery is very small. 2.Chest X-ray: Chest X-ray is essential to assess the degree of development of PAH. By studying the chest X-ray, we can roughly grasp the degree of development of pulmonary artery lesions and predict the feasibility and clinical effect of surgery. Although there is a lack of quantitative objective criteria, experienced physicians attach more importance to chest radiographs than even right heart catheterization. 3. ECG: Patients with PAH will present with typical ECG manifestations (e.g. pulmonary P waves). More importantly, the ECG can reflect the right and left ventricular hypertrophy. If the patient has predominantly left ventricular hypertrophy, it often suggests that the surgery can be performed safely; whereas if it is biventricular hypertrophy, or even predominantly right ventricular hypertrophy, the safety of the surgery will be greatly compromised. 4, echocardiography: echocardiography is the most important test to confirm the diagnosis of precordial disease and pulmonary hypertension, and is the basic basis for clinical diagnosis. If the echocardiogram indicates that the type of precordial disease originally “left-to-right shunt” evolves into “bidirectional shunt” or even “right-to-left shunt”, it means that the patient has developed severe pulmonary hypertension. It is important to note, however, that even if the shunt is not a right-to-left shunt, the patient may have a severe pulmonary hypertension. However, it is important to note that even if the direction of the shunt has changed, it does not mean that the patient is completely lost to surgery (although this is true in most patients), and jumping to conclusions based on ultrasound alone may deprive the patient of the last chance for correction. 5. Right heart catheterization and rapid pulmonary artery dilation test: right heart catheterization is by far the most objective, effective and authoritative means of assessing pulmonary hypertension. Through right heart catheterization, the patient’s pulmonary artery pressure, body/pulmonary circulation blood volume and pulmonary artery resistance can be accurately measured. Of these, pulmonary artery resistance is the key data to determine whether the patient can be operated (although other indices are also important). The so-called rapid pulmonary artery dilation test is done after adequate oxygenation or inhalation of pulmonary artery dilation drugs, followed by completion of a right heart catheterization. The aim is to exclude interference from functional factors such as pulmonary artery spasm and to more accurately measure the extent of disease development in the pulmonary vasculature itself. Therefore, we recommend that all patients with PAH undergo standardized right heart catheterization and rapid pulmonary artery dilation test; for patients with PAH in combination with precordial disease, even if they are inoperable, they should undergo this test to grasp the current progression of pulmonary hypertension, which can be used as a yardstick to guide drug therapy.