1, morbidity and mortality IPAH and FPAH are basically the same in terms of disease derivation and regression, their prognosis is very poor, 20 years ago by the National Institutes of Health (NIH) funded the National PPH Registry study showed that the incidence of PPH is 1 to 2 per million people, of which 6% are FPAH patients, the study collected a total of 194 patients, the average age of 36 years, female and male The median survival time for untreated patients was 2.8 years, and the survival rates at 1, 3 and 5 years were 68%, 48% and 34%, respectively. and 34%, similar to malignancy. The mean survival time for patients with class IV cardiac function was 6 months. Pediatric patients may have a worse prognosis than adults, with a median survival time of only 10 months, but the sample size of pediatric patients in this study was small. A domestic registry collected 72 patients with IPHA and FPAH with a mean age of 35.9 years and a follow-up of 40.1 ± 20 months, with survival rates of 68.0%, 56.9%, 38.9%, and 20.8% at 1, 2, 3, and 5 years, respectively, which are essentially similar to the NIH study [5]. 2. Genetic characteristics Heterozygous mutations in the Bone morphogenetic protein type II receptor (BMPR2) gene are the etiological basis of most FPAH, and mutations in the BMPR2 gene can be detected in 50% to 90% of patients with FPAH, in addition, in 25% of patients with IPAH and Mutations in the BMPR2 gene are also detectable in 15% of patients with pulmonary hypertension due to fenfluramine administration, and these cases may present with spontaneous mutations in this gene, or they may be patients with FPAH that has not yet been identified. To date, more than 140 different mutated loci of BMPR2 have been identified in FPAH cases and cases of IPAH, including partial gene fragment deletions, missense mutations, shearing abnormalities, nonsense mutations and code-shifting mutations. Two BMPR2 mutant loci have been reported in the national population. FPAH is an autosomal incomplete dominant disorder, and the relationship between genotype and phenotype of the disease is not clear enough to predict whether an individual carrying the causative gene will develop the disease, the age of onset, and the severity and rate of progression of the disease based on his or her genotype. FPAH has a genetic anticipation phenomenon, i.e., the age of onset of the disease is advanced from generation to generation and the symptoms of the disease are aggravated from generation to generation. The pathology and pathophysiological mechanisms of IPAH and FPAH are similar in terms of histopathological changes, with lesions mainly in small arteries and small arteries in the pulmonary circulation. vasoproliferative plexiform lesions, etc. Under normal conditions, the pulmonary circulation is a high volume, low pressure and low resistance system. The above pathological changes cause increasing pulmonary artery pressure and pulmonary vascular resistance, eventually leading to progressive right heart failure and even death. BMPR2 is a member of the transforming growth factor beta (TGF-beta) superfamily, which plays an important role in regulating cell growth and differentiation, but the relationship between mutations in the BMPR2 gene and pulmonary vascular lesions has not been completely clarified. It is now generally believed that BMPR2, when bound to its ligand, can be activated by When BMPR2 gene is heterozygous for a mutation, the Smad signaling pathway is partially blocked and its antiproliferative effect is diminished because the protein product of the mutant heterozygote is reduced and is not sufficient to exercise normal function, resulting in the proliferation and apoptosis of pulmonary vascular smooth muscle cells. The imbalance between proliferation and apoptosis of pulmonary vascular smooth muscle cells eventually leads to pulmonary vascular disease. In addition, because of the low ectopic rate of the disease, it is suggested that some other genetic or environmental factors may also be involved in the development of the disease. 4. Genetic testing The positive detection rate of gene mutations in patients with FPAH is increasing due to improvements in detection methods. In the past, the most common method was to sequence the protein-coding region and the exon/intron junction of the BMPR2 gene, but the positive detection rate was only about 50%, and then multiplex ligation-dependent probe amplification (MLPA) combined with real-time polymerase chain reaction (real-time PCR) was used. In addition, reverse transcription polymerase chain reaction (RT-PCR) combined with sequencing analysis can improve the detection rate of splicing abnormalities. At present, mutations in the BMPR2 gene can be detected in about 70-90% of FPAH patients, and a few experimental centers abroad have included it in their clinical testing programs, but in China it is limited to scientific work. 5.Diagnosis and differential diagnosis Because pulmonary hypertension itself has no specific clinical manifestations, diagnosis is sometimes difficult, especially in pediatric patients, who are easily misdiagnosed as other cardiopulmonary diseases. In the early stage, there are no conscious symptoms when the pulmonary artery pressure is mildly elevated, but symptoms such as shortness of breath after activity, fatigue, chest pain, syncope and hemoptysis appear as the disease progresses. Right heart catheterization can confirm the diagnosis of pulmonary hypertension, and the diagnostic criteria for pulmonary hypertension are mean pulmonary artery pressure >25 mmHg in the quiet state and >30 mmHg in the active state, and pulmonary capillary pressure or left atrial pressure.