The "definition" of pulmonary hypertension has been rewritten?

*Only for medical professionals to read for reference.
Solving right heart failure is the key to improving the prognosis of CTD-PAH patients.

On March 26-28, 2021, the “First National Skin and Disease Association” jointly sponsored by the China Systemic Lupus Erythematosus Research Collaboration Group (CSTAR), the National Rheumatism Data Center (CRDC) and the Chinese Rheumatology Association (CRCA) The annual meeting of the Clinical Research Center for Immunological Diseases and the CSTAR/CRDC/CRCA Annual Meeting" was successfully held in Beijing.

With the theme of "Going International, Drawing the Future Together", based on the results of years of international exchanges and cooperation between CSTAR and CRDC, well-known experts in related fields at home and abroad were invited to focus on the latest disciplines of rheumatism and immunology.
Special reports were made on progress, hot issues and innovative methods in disease diagnosis and treatment.

Among them, Professor Wang Qian from the Department of Rheumatology and Immunology, Peking Union Medical College Hospital, gave a wonderful introduction to connective tissue disease pulmonary hypertension (CTD-PAH) and right heart injury, which are summarized as follows.

1What is CTD-PAH? The bright spot of CTD-PAH definition change-mean pulmonary artery pressure (mPAP) threshold decreased from 25mmHg to 20mmHg.

In 1973, the First Pulmonary Hypertension Conference (WSPH) defined PAH as a state where mPAP>25mmHg measured by a right heart catheter in a supine position in a resting state.
This standard was adopted by successive WSPHs.

From 1973 to 2018, the hemodynamic characteristics of PAH were defined as: mPAP>25mmHg, pulmonary artery wedge pressure (PAWP)<15mmHg, and pulmonary vascular resistance (PVR)>3WU in resting state measured by right heart catheter.

However, in recent years, academia has tended to lower the threshold of PAH definition from "mPAP>25mmHg" to "20mmHg".
Professor Wang Qian also expressed his recognition of this concept and explained that under the physiological state of the human body (at sea level) ) The average pulmonary artery pressure is about 14mmHg, 20~25mmHg is a "gray area" between normal pulmonary artery blood pressure and PAH.

In order to reduce the mortality of PAH, which is a disabling disease, it is recommended to lower the threshold of disease diagnosis.

In addition, Professor Wang Qian added that in PAH, the PVR indicator is often ignored by people, but it is precisely the most important and the essence of PAH.

2 The type of primary disease and the function of the right heart determine the prognosis of CTD-PAH.
The overall prognosis of CTD-PAH is poor, but for individuals, the prognosis is different.
There are two factors that affect the prognosis the most-the type of primary disease And right heart function.

Types of CTD-PAH primary disease The primary disease of CTD-PAH varies significantly among different regions.

If you search for CTD-PAH on PubMed, it can be seen that the proportion of systemic scleroderma (SSc) reported in European and American countries accounts for 3/4 of the CTD, while in my country, systemic lupus erythematosus (SLE) accounts for half of the country (49%).

The prognosis of different types of CTD patients is very different.
The 5-year survival rate of SLE-PAH and primary Sjogren’s syndrome pulmonary hypertension (pSS-PAH) is similar, reaching more than 60%, while the 5-year survival rate of SSc-PAH is only Is 43.
9%.

Whether PAH is combined with right heart failure PAH is a serious complication of CTD and the third leading cause of death in CTD patients.
Among them, the first cause of hospitalization and death in CTD-PAH patients is right heart failure.

Figure 1 Right heart failure is the leading cause of PAH hospitalization and death.
A prospective study that included 205 inpatient PAH patients from Johns Hopkins Hospital and its affiliated hospitals from 2000 to 2009 showed that right heart failure was the leading cause of hospitalization , Reaching 56.
1%, which is significantly higher than the second cause of infection, 15.
6%; the inpatient mortality rate of right heart failure is 14%, and the progression of right heart failure is the first cause of hospital death, reaching 81.
3%.

Therefore, Professor Wang Qian proposed that solving right heart failure is the key to improving the prognosis of CTD-PAH patients, and suggested that when treating patients with pulmonary hypertension, doctors should not only pay attention to the degree of pulmonary hypertension in the cardiac color Doppler ultrasound report, but also pay attention to An indicator of right heart function.

3How to improve the survival rate of CTD-PAH patients? The answer is to actively screen the right heart function.

CTD-PAH right ventricular remodeling can occur in the early stage, that is, when the afterload of the right ventricle is higher than normal (the patient may have no symptoms), the myocardium of the right ventricle may have begun to remodel and bring about an increase in systolic blood pressure.
A series of changes such as height and myocardial enlargement.

Among them, the fibrotic course of SSc itself can affect the myocardium, accelerate myocardial remodeling, and its right ventricular changes are more difficult to treat.

Figure 2 The complex relationship between the mechanism of right ventricular dysfunction and remodeling Professor Wang Qian said that PAH is a disease that "cannot be lost on the starting line", even if the treatment plan is the same, "active screening and timely intervention" and "after symptoms appear" "Passive inspection and intervention" can be described as a small difference and a thousand miles away.

A French PAH registration study established in 2002 supports this point.

The study included PAH patients from 21 SSc centers from September 2002 to July 2003, of which 32 patients had complete data, and 16 patients were diagnosed only after right heart catheterization at the time of enrollment.
, Was assigned to the routine diagnosis group, and the other 16 patients who were actively screened were assigned to the active screening group.
The study compared the long-term survival of the two groups of patients.

The results showed that the 3-year, 5-year and 8-year survival rates of patients in the active screening group were significantly higher than those in the routine group (p=0.
0037).

Figure 3 The 3-year, 5-year, and 8-year survival rates of patients in the active screening group were significantly higher than those in the routine group.
The screening recommendations for common CTD-PAH can refer to the following table.

Table 1 Common CTD-PAH Screening Recommendations 4 Three Steps to Diagnose CTD-PAH Keep in mind that screening is the core step! Step 1: Screening of high-risk groups (core step) Echocardiography is the most important non-invasive examination method for screening.
Professor Wang Qian believes that we should actively carry out regular echocardiographic screening for people at high risk of pulmonary hypertension.

Figure 4 The standard procedure for evaluating the probability of pulmonary hypertension with echocardiography.
Step 2: Excluding Type 2/Type 3 PH.
Identify whether there is left heart or lung disease through lung examination (HRCT/PFT) and cardiac examination (UCG).

Step 3: Exclude Type 4 PH and confirm whether there is a perfusion defect through lung ventilation/perfusion scan.

Figure 5 CTD-PAH diagnosis process 5 After the diagnosis of PAH, these 3 methods should not be forgotten! Method 1: Echocardiography All patients suspected of right heart failure should be screened by transthoracic echocardiography.

Table 2 Echocardiographic risk stratification of PAH patients Method 2: Cardiac Magnetic Resonance (MRI) has the advantage of presenting a three-dimensional structure, which is the most intuitive and comprehensive method for evaluating the function and structure of the right heart.

In MRI, right ventricular ejection fraction is the strongest predictor of PAH death.
Right ventricular end-diastolic volume, end-systolic volume and right ventricular mass also have important predictive significance for disease progression.

For every 1% decrease in right ventricular ejection fraction, the risk of death in PAH patients increases by 5%; for every increase in right ventricular end diastolic volume index by 1 ml/m2, the risk of disease in PAH patients increases by 1%; for every increase in right ventricular end systolic volume index by 1 ml/m2 m2, the disease risk of PAH patients increases by 1%; for every increase of 1g/m2 in the right ventricular mass parameter, the disease risk of PAH patients increases by 3%.

Method 3: Right heart catheterization Right heart catheterization is the gold standard for the diagnosis of PAH.
If the diagnosis cannot be confirmed through non-invasive examination, right heart catheterization is recommended.

In addition to directly measuring the pulmonary artery pressure, it also measures related right heart function parameters to predict the prognosis of the disease.

It should be noted that the mPAP value decreases when the right ventricular function fails in the late stage of the disease, so the reliability is poor.

The main indicators for evaluating right ventricular function are right atrial pressure (RAP) and cardiac index (CI), and the indicator for evaluating pulmonary artery remodeling is PVR.

For every 5mmHg increase in RAP, the risk of death increased by 30%; for every 1L/(min·m2) increase in CI, the risk of death decreased by 21%.

Figure 61 understands how to treat PAH.
Finally, Professor Wang Qian summarized the treatment strategy of PAH, as shown in the flowchart.

Figure 6 The treatment strategy of PAH.
Supportive therapy is a treatment to relieve right ventricular preload, while targeted therapy is a treatment for increased pulmonary circulatory resistance, that is, a treatment to reduce right ventricular afterload.

The combination of several treatment strategies is an important strategy to improve right ventricular remodeling.

7 Summary Professor Wang Qian, as an expert in the field of rheumatism and immunity, pointed out in this report that the overall prognosis of CTD-PAH is poor, and right heart failure is the first cause of hospitalization and death, and calls on colleagues to pay attention to the importance of CTD-PAH Problems, especially related indicators of right ventricular function.

Right ventricular remodeling can occur early in the course of CTD.
When high-risk patients are encountered, the right ventricular function can be screened as soon as possible, which can significantly improve the prognosis of patients.

At the same time, Professor Wang Qian suggested that doctors regularly assess the patient's right heart function during CTD-PAH treatment and adjust the treatment plan in time.