| Pulmonary artery hypertension(PAH) is a common pathophysiological state in many diseases of lung,chest and heart,especially chronic obstructive pulmonary diseases(COPD).The morbidity and mortality of COPD are both very high, whose fatality rate was the fourth in USA in 1997, and will be the third in 2020. In China, the incidence rate of pulmonary heart disease (PHD) caused by COPD has ascended to the frist place in all organic heart diseases in recent years. COPD is characteristic of airflow being limited in airway. This procedure is incompletely reversible and progressing development, which is concerned with the inflammatory reaction caused by gases and granules that are harmful to lung.The pathophysiological processes of COPD are processing decreasing expiratory gas, increasing residual volume, hypoxemia, hypercapnia and pulmonary hypertension.The prognosis of PHD is bad, so we should apply combined therapy, including anti-infection, relieving airway obstruction, redressing acid-base imbalance and symptomatic reatment, etc. Because pulmonary hypertension play important roles in the development and prognosis of PHD, it is very significant to diagnose and treat pulmonary hypertension early for postponing the progression of PHD and depressing the fatality ratio.The pulmonary circulation is a system with high flow and low pressure. In normal condition, the systolic pressure of pulmonary artery (SPAP) is about 20mmHg(2.67kpa), the diastolic pressure (DPAP) is about 10mmHg(1.33kpa),and the mean pulmonary artery pressure (MPAP) is about 14mmHg(1.53kpa)。According to the diagnostic standard of WHO, the conception of pulmonary hypertension is the pathologic status that the SPAP is more than 4.0kPa(30mmHg) ,the DPAP is more than 2.4kPa(18mmHg) and the MPAP is more than 3.33kPa(25mmHg). But the diagnostic standard of PAH that is more accepted in internal and overseas at present is that the MPAP≥2.67kPa(20mmHg) at resting state or MPAP≥4.0kPa(30mmHg) at activity state.At present, there are many kinds of diadynamic methods about PAH, which can be divided into traumatic check and uninjurious one. The former contains the catheterization of right heart and lung biopsy. The classic measurement of the pressure of pulmonary artery is by cardiac catheter of right heart, and the gold standard of PAH is also this method. But because of the expensive equipment,the complex operation and more complication,the cardiac catheterization couldn't be popularized easily. Since the appearance of Doppler echocardiography, the uninjurous measurements of the pressure of pulmonary artery has been realized.Doppler echocardiography can provide many important information for the diagnosis, therapy and research of PHD. It can not only provide the morphological change of heart by measuring cardiac volume, the width of the pulmonary artery, the ventricular thickness and the movement of interventricular septum, but also give the quantitative diagnosis of PAH. Doppler echocardiography is superior to other methods for its features of uninjury, high-sensitivity and easy reduplication in the measurement of PAH. It can show the structure of heart, the movement of interventricular septum and the phase of the systole and diastole of heart. So Doppler echocardiography not only is very valuable to the etiological diagnosis, the qualitative and quantitative diagnosis of PAH, but also can be used in evaluation of prognosis and therapeutic effect. Because of the augmentation of right ventricle and thickening of pulmonary artery, the relative tricuspid insufficiency and pulmonary artery valve insufficiency can be seen in patients with PAH. And it has been very easy to detect the relative tricuspid insufficiency since Doppler echocardiography is applied in clinic. Because we can record the PVTR by measuring regurgitant spectra with Doppler echocardiography and the regurgitant rate of tricuspid valve (PVTR) is decided by the pressure difference of two sides of which, we can calculateΔP, according...
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