Bronchopulmonary Dysplasia-Associated Pulmonary Hypertension: Basing Care on Physiology.

Bronchopulmonary dysplasia (BPD) is the heterogeneous chronic lung developmental disease of prematurity, which is often accompanied by multisystem comorbidities. Pulmonary vascular disease and pulmonary hypertension (PH) contribute significantly to the pathogenesis and pathophysiology of BPD and dramatically influence the outcomes of preterm infants with BPD. When caring for those patients, clinicians should consider the multitude of phenotypic presentations that fall under the "BPD-PH umbrella," reflecting the need for matching therapies to specific physiologies to improve short- and long-term outcomes. Individualized management based on the patient's prenatal and postnatal risk factors, clinical course, and cardiopulmonary phenotype needs to be identified and prioritized to provide optimal care for infants with BPD-PH.

[Guidelines for the diagnosis and treatment of chronic thromboembolic pulmonary hypertension (2024 edition)].

Chronic thromboembolic pulmonary hypertension (CTEPH) is classified as group 4 pulmonary hypertension, characterized by pulmonary arterial thrombotic occlusion leading to vascular stenosis or obstruction, progressive elevation of pulmonary vascular resistance and pulmonary arterial pressure, ultimately leading to right heart failure and even death. Recent years have seen rapid progress in the diagnostic and therapeutic in CTEPH field. More and more patients with CTEPH have been accurately diagnosed and assessed in time. Nevertheless, there is still a lot of work to do in the popularization of CTEPH diagnostic and therapeutic technique and the building of CTEPH expert center. To better guide clinical practice in our country, Pulmonary Embolism & Pulmonary Vascular Diseases Group of the Chinese Thoracic Society, Pulmonary Embolism & Pulmonary Vascular Disease Working Group of Chinese Association of Chest Physicians, National Cooperation Group on Prevention & Treatment of Pulmonary Embolism & Pulmonary Vascular Disease, National Expert Panel on the Development of a Standardized Framework for Pulmonary Arterial Hypertension, convened multidisciplinary experts for deliberation and Delphi expert consensus to develop the "Guidelines for the Diagnosis and Treatment of Chronic Thromboembolic Pulmonary Hypertension (2024 edition) ". These guidelines systematically evaluate domestic and international evidence-based medical research on CTEPH and propose recommendations tailored to clinical practice in our country. The key areas covered include definitions, epidemiology, pathogenesis, diagnosis and assessment, treatment, and management, with the aim of further standardizing the clinical diagnosis and treatment of CTEPH in our country.

Serum ASGR2 level: an efficacy biomarker for balloon pulmonary angioplasty in patients with chronic thromboembolic pulmonary hypertension.

Background: This study aimed to employ plasma proteomics to investigate the molecular changes, pathway alterations, and potential novel biochemical markers associated with balloon pulmonary angioplasty (BPA) in patients with chronic thromboembolic pulmonary hypertension (CTEPH). Methods: Pre- and post-BPA plasma samples from five CTEPH patients in the PRACTICE study were analyzed to identify differentially expressed proteins. Proteomic and bioinformatics analyses were conducted, and the identified proteins were further validated using ELISA assays in a separate cohort of the same study. Correlation and multivariate regression analyses were performed to investigate the associations between these differentially expressed proteins and clinical parameters. Results: Significantly higher serum levels of asialoglycoprotein receptor 2 (ASGR2) were detected in 5 CTEPH patients compared to those in healthy individuals but decreased significantly after successful BPA procedures. The decrease in serum levels of ASGR2 after the completion of BPA procedures was further validated in a separate cohort of 48 patients with CTEPH [0.70 (0.51, 1.11) ng/mL vs. 0.38 (0.27, 0.59) ng/mL, P < 0.001]. Significant associations were found between the pre-BPA ASGR2 level and clinical parameters, including neutrophil percentage (R = 0.285, P < 0.05), platelet (PLT) count (R = 0.386, P < 0.05), and high-density lipoprotein cholesterol (HDL-C) before BPA (R = -0.285, P < 0.05). Significant associations were detected between post-BPA serum ASGR2 levels and lymphocyte percentage (LYM%) (R = 0.306, P < 0.05), neutrophil-to-lymphocyte ratio (R = -0.294, P < 0.05), and pulmonary vascular resistance after BPA (R = -0.35, P < 0.05). Multivariate stepwise regression analysis revealed that pre-BPA ASGR2 levels were associated with HDL-C and PLT count (both P < 0.001), while post-BPA ASGR2 levels were associated with LYM% (P < 0.05). Conclusion: Serum levels of ASGR2 may be a biomarker for the effectiveness of BPA treatment in CTEPH patients. The pre-BPA serum level of ASGR2 in CTEPH patients was associated with HDL-C and the PLT count. The post-BPA serum level of ASGR2 was correlated with the LYM%, which may reflect aspects of immune and inflammatory status.

The management pattern and outcomes of chronic thromboembolic pulmonary hypertension: rationale and design for a Chinese real-world study.

BACKGROUND: Chronic thromboembolic pulmonary hypertension (CTEPH) is a progressive pulmonary vascular disorder with substantial morbidity and mortality, also a disease underdiagnosed and undertreated. It is potentially curable by pulmonary endarterectomy (PEA) in patients with surgically accessible thrombi. Balloon pulmonary angioplasty (BPA) and targeted medical therapy are options for patients with distal lesions or persistent/recurrent pulmonary hypertension after PEA. There is an urgent need to increase the awareness of CTEPH. Qualified CTEPH centers are still quite limited. Baseline characteristics, management pattern and clinical outcome of CTEPH in China needs to be reported. METHODS AND DESIGN: The CHinese reAl-world study to iNvestigate the manaGEment pattern and outcomes of chronic thromboembolic pulmonary hypertension (CHANGE) study is designed to provide the multimodality treatment pattern and clinical outcomes of CTEPH in China. Consecutive patients who are ≥ 14 year-old and diagnosed with CTEPH are enrolled. The diagnosis of CTEPH is confirmed in right heart catheterization and imaging examinations. The multimodality therapeutic strategy, which consists of PEA, BPA and targeted medical therapy, is made by a multidisciplinary team. The blood sample and tissue from PEA are stored in the central biobank for further research. The patients receive regular follow-up every 3 or 6 months for at least 3 years. The primary outcomes include all-cause mortality and changes in functional and hemodynamic parameters from baseline. The secondary outcomes include the proportion of patients experiencing lung transplantation, the proportion of patients experiencing heart and lung transplantation, and changes in health-related quality of life. Up to 31 December 2023, the study has enrolled 1500 eligible patients from 18 expert centers. CONCLUSIONS: As a real-world study, the CHANGE study is expected to increase our understanding of CTEPH, and to fill the gap between guidelines and the clinical practice in the diagnosis, assessment and treatment of patients with CTEPH. REGISTRATION NUMBER IN CLINICALTRIALS.GOV: NCT05311072.

Novel insights into the potential applications of stem cells in pulmonary hypertension therapy.

Pulmonary hypertension (PH) refers to a group of deadly lung diseases characterized by vascular lesions in the microvasculature and a progressive increase in pulmonary vascular resistance. The prevalence of PH has increased over time. Currently, the treatment options available for PH patients have limited efficacy, and none of them can fundamentally reverse pulmonary vascular remodeling. Stem cells represent an ideal seed with proven efficacy in clinical studies focusing on liver, cardiovascular, and nerve diseases. Since the potential therapeutic effect of mesenchymal stem cells (MSCs) on PH was first reported in 2006, many studies have demonstrated the efficacy of stem cells in PH animal models and suggested that stem cells can help slow the deterioration of lung tissue. Existing PH treatment studies basically focus on the paracrine action of stem cells, including protein regulation, exosome pathway, and cell signaling; however, the specific mechanisms have not yet been clarified. Apoptotic and afunctional pulmonary microvascular endothelial cells (PMVECs) and alveolar epithelial cells (AECs) are two fundamental promoters of PH although they have not been extensively studied by researchers. This review mainly focuses on the supportive communication and interaction between PMVECs and AECs as well as the potential restorative effect of stem cells on their injury. In the future, more studies are needed to prove these effects and explore more radical cures for PH.

Venous retrograde approach for endovascular angioplasty in chronic total pulmonary vein occlusion -a case report.

INTRODUCTION: Fibrosing mediastinitis (FM) is a rare disease characterized by excessive proliferation of fibrous tissue in the mediastinum and can cause bronchial stenosis, superior vena cava obstruction, pulmonary artery and vein stenosis, etc. CASE PRESENTATION: An aging patient with intermittent chest tightness and shortness of breath was diagnosed with FM associated pulmonary hypertension (FM-PH) by echocardiography and enhanced CT of the chest, and CT pulmonary artery (PA)/ pulmonary vein (PV) imaging revealed PA and PV stenosis. Selective angiography revealed complete occlusion of the right upper PV, and we performed endovascular intervention of the total occluded PV. After failure of the antegrade approach, the angiogram revealed well-developed collaterals of the occluded RSPV-V2b, so we chose to proceed via the retrograde approach. We successfully opened the occluded right upper PV and implanted a stent. CONCLUSIONS: This report may provide new management ideas for the interventional treatment of PV occlusion.

Ultrasound Neuromodulation of an Anti-Inflammatory Pathway at the Spleen Improves Experimental Pulmonary Hypertension.

BACKGROUND: Inflammation is pathogenically implicated in pulmonary arterial hypertension; however, it has not been adequately targeted therapeutically. We investigated whether neuromodulation of an anti-inflammatory neuroimmune pathway involving the splenic nerve using noninvasive, focused ultrasound stimulation of the spleen (sFUS) can improve experimental pulmonary hypertension. METHODS: Pulmonary hypertension was induced in rats either by Sugen 5416 (20 mg/kg SQ) injection, followed by 21 (or 35) days of hypoxia (sugen/hypoxia model), or by monocrotaline (60 mg/kg IP) injection (monocrotaline model). Animals were randomized to receive either 12-minute-long sessions of sFUS daily or sham stimulation for 14 days. Catheterizations, echocardiography, indices of autonomic function, lung and heart histology and immunohistochemistry, spleen flow cytometry, and lung single-cell RNA sequencing were performed after treatment to assess the effects of sFUS. RESULTS: Splenic denervation right before induction of pulmonary hypertension results in a more severe disease phenotype. In both sugen/hypoxia and monocrotaline models, sFUS treatment reduces right ventricular systolic pressure by 25% to 30% compared with sham treatment, without affecting systemic pressure, and improves right ventricular function and autonomic indices. sFUS reduces wall thickness, apoptosis, and proliferation in small pulmonary arterioles, suppresses CD3+ and CD68+ cell infiltration in lungs and right ventricular fibrosis and hypertrophy and lowers BNP (brain natriuretic peptide). Beneficial effects persist for weeks after sFUS discontinuation and are more robust with early and longer treatment. Splenic denervation abolishes sFUS therapeutic benefits. sFUS partially normalizes CD68+ and CD8+ T-cell counts in the spleen and downregulates several inflammatory genes and pathways in nonclassical and classical monocytes and macrophages in the lung. Differentially expressed genes in those cell types are significantly enriched for human pulmonary arterial hypertension-associated genes. CONCLUSIONS: sFUS causes dose-dependent, sustained improvement of hemodynamic, autonomic, laboratory, and pathological manifestations in 2 models of experimental pulmonary hypertension. Mechanistically, sFUS normalizes immune cell populations in the spleen and downregulates inflammatory genes and pathways in the lung, many of which are relevant in human disease.

Usefulness of risk assessment tools in predicting hemodynamic outcome after balloon pulmonary angioplasty: a comparative analysis.

OBJECTIVES: Several parameters of widely used risk assessment tools for pulmonary arterial hypertension (PAH) have been linked to hemodynamic outcomes of balloon pulmonary angioplasty (BPA). Therefore, we aimed to determine whether these risk assessment tools could be used to predict hemodynamic outcomes following BPA. METHODS: In this retrospective study, we included 139 patients with chronic thromboembolic pulmonary hypertension who had undergone BPA at Center for Pulmonary Vascular Diseases, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College (Beijing, China). We compared the accuracies of seven well-validated risk assessment tools for predicting hemodynamic outcomes following BPA. A favorable hemodynamic outcome was defined as a mean pulmonary arterial pressure < 30 mmHg at follow-up. RESULTS: The baseline risk profiles varied significantly among the risk assessment tools. The US Registry to Evaluate Early and Long-Term PAH Disease Management risk scales and the French risk assessment tools rated most patients as high-risk, while the Comparative, Prospective Registry of Newly Initiated Therapies for Pulmonary Hypertension (COMPERA) series and laboratory examination-based risk scales categorized most patients as having intermediate-risk profile. COMPERA 2.0 (4-strata) exhibited the highest predictive power among all risk stratifications. Noninvasive risk stratification (COMPERA 2.0 [3-strata]) showed a comparable predictive ability to that of invasive risk stratification (COMPERA 1.0) (area under the curve 0.649 vs. 0.648). Moreover, incorporating diffusing capacity of the lungs for carbon monoxide and tricuspid regurgitation velocity into COMPERA 2.0 (4-strata) further enhanced its predictive power (net reclassification index 0.153, 95% confidence interval 0.009-0.298, p = 0.038). Additionally, this refined COMPERA version had a high calibration accuracy (slope 0.96). CONCLUSION: Although the risk strata distribution varied among different risk assessment tools, the proportion of patients achieving favorable hemodynamics decreased with the escalation of risk stratification in most models. The well-validated risk assessment tools for PAH could also predict hemodynamic outcomes following BPA, and the refined COMPERA 2.0 model exhibited the highest predictive ability among these. Applying risk assessment tools before BPA can facilitate early identification of patients in need of closer monitoring and more intensive interventions, contributing to a better prognosis after BPA.

Pulmo-protection of long-term swimming exercise via improving insulin sensitivity in monocrotaline-induced pulmonary hypertensive rats.

Exercise has been recognized as an effective intervention in the treatment of pulmonary arterial hypertension (PAH), supported by numerous studies. However, the precise effects of exercise on pulmonary function remain to be fully elucidated. In this study, using a rat model of swimming exercise training and monocrotaline-induced PAH, we aimed to explore its impact on pulmonary morphology and function. Our investigations revealed that MCT-treated rats exhibited augmented mean pulmonary arterial pressure (MPAP) and pulmonary vascular remodeling, which can be attenuated by 4 weeks of swimming exercise training (60 min/day, 5 days/week). Notably, MCT-treated rats showed impaired pulmonary function, as manifested by decreased tidal volume and dynamic compliance, which were reversed by exercise training. Assessment of pulmonary substrate in PAH rats indicated a prominent pro-inflammatory substrate, evidenced by macrophage accumulation through quantitative immunohistological analysis of macrophage-like cell expression (CD68), and extracellular matrix remodeling, evaluated by Masson staining. Importantly, both the pro-inflammatory substrate and extracellular matrix remodeling were ameliorated by swimming exercise training. Additionally, serum biochemical analysis demonstrated elevated levels of low-density lipoprotein cholesterol and Apolipoprotein B following MCT treatment, which were reduced with exercise intervention. Moreover, exercise enhanced systemic insulin sensitivity in both MCT-treated and untreated rats. Notably, MCT and exercise treatment both decreased fasting blood glucose (FBG) levels in rats, whereas exercise training reinstated FBG levels to normal in MCT-treated rats. In summary, our study suggests that swimming exercise confers a pulmonary protective effect in MCT-induced PAH rats, highlighting the potential importance of exercise-based rehabilitation in the management of PAH.

[Heritable pulmonary arterial hypertension]. / Hereditäre pulmonal-arterielle Hypertonie.

Heritable pulmonary arterial hypertension (PAH) can be triggered by at least 18 genes. The most frequently altered gene is the bone morphogenetic protein receptor 2 (BMPR2). Further genes from the same pathway are also well known PAH-causing genes. Genetic testing can aid to confirm differential diagnoses such as a pulmonary veno-occlusive disease. It also enables the testing of healthy family members. In addition to the PAH patient population particularly served by genetic testing, this article touches on the mode of inheritance and provides insights into the first treatments soon on the market that rebalance the BMPR2 signaling pathway.

Right heart catheterization in idiopathic pulmonary hypertension: An all-inclusive necessity.

The gold standard for diagnosis of pulmonary hypertension is right heart catheterization. This procedure requires considerable expertise and has its own procedure related complications. If not done properly, it can lead to misinterpretations of its findings. We have highlighted the procedural technique and major pitfalls in the diagnosis of pulmonary hypertension.

Native hepatic T1-time as a non-invasive predictor of diastolic dysfunction and a monitoring tool for disease progression and treatment response in patients with pulmonary hypertension.

AIMS: Hepatic T1-time derived from cardiac magnetic resonance imaging (cMRI) reflects venous congestion and may provide a simple alternative to invasive end-diastolic elastance (Eed) for assessment of right ventricular (RV) diastolic function. We investigated the association of native hepatic T1-time with single-beat Eed and the value of hepatic T1-time for longitudinal monitoring in pulmonary hypertension (PH). METHODS AND RESULTS: We retrospectively enrolled 85 patients with suspected PH (59% female; 78 with PH diagnosed; 7 with PH excluded) who underwent standard right heart catheterization and cMRI within 24 h between 2015 and 2020. Hepatic T1-time showed moderate to strong correlations (rho >0.3, P ≤ 0.002) with pulmonary vascular resistance, native myocardial T1-time, Eed, RV size and function, brain natriuretic peptide (BNP) level, and 6-min walk distance, and a significant association with functional class (Kruskal-Wallis P < 0.001). Eed, myocardial T1-time, and BNP were independently linked to hepatic T1-time in multivariable regression. Hepatic T1-time > 598 ms predicted elevated Eed with 72.9% sensitivity and 82.1% specificity. Hepatic T1-time was superior to Eed in predicting clinical worsening. In 16 patients with follow-up assessments, those with decreasing hepatic T1-time (7 patients) showed significant hemodynamic improvements, whereas those with increasing hepatic T1-time (9 patients) did not. In a second retrospective cohort of 27 patients with chronic thromboembolic PH undergoing balloon pulmonary angioplasty, hepatic T1-time decreased significantly and hemodynamics improved after the procedure. CONCLUSIONS: Hepatic T1-time predicts RV diastolic dysfunction and prognosis, and may be useful for monitoring disease progression and treatment response in PH.

Cardiovascular Complications With Delivery Hospitalizations in Patients With Pulmonary Hypertension: A Nationwide Study From 2011 to 2020.

BACKGROUND: Pregnancy in patients with pulmonary hypertension (PH) is associated with a heightened risk of medical complications including right heart failure, pulmonary edema, and arrhythmias. Our study investigated the association between PH and these complications during delivery. METHODS AND RESULTS: The National Inpatient Sample was used to identify delivery hospitalizations from 2011 to 2020. Multivariable logistic regression was performed to study the association of PH with the primary outcomes of in-hospital medical and obstetric complications. A total of 37 482 207 delivery hospitalizations in women ≥18 years of age were identified, of which 9593 patients had PH. Pregnant patients with PH had higher incidence of complications during delivery including preeclampsia/eclampsia, arrhythmias, and pulmonary edema among others, compared with those without PH. Pregnant patients with PH also had a higher incidence of in-hospital mortality compared with those without PH (0.51% versus 0.007%). In propensity-matched analyses, PH was still significantly associated with a higher risk of in-hospital mortality (odds ratio [OR], 5.02 [95% CI, 1.82-13.90]; P=0.001), pulmonary edema (OR, 9.11 [95% CI, 6.34-13.10]; P<0.001), peripartum cardiomyopathy (OR, 1.85 [95% CI, 1.37-2.50]; P<0.001), venous thromboembolism (OR, 12.60 [95% CI, 6.04-26.10]; P<0.001), cardiac arrhythmias (OR, 6.11 [95% CI, 4.97-7.53]; P<0.001), acute kidney injury (OR, 3.72 [95% CI, 2.86-4.84]; P<0.001), preeclampsia/eclampsia (OR, 2.24 [95% CI, 1.95-2.58]; P<0.001), and acute coronary syndrome (OR, 2.01 [95% CI, 1.06-3.80]; P=0.03), compared with pregnant patients without PH. CONCLUSIONS: Delivery hospitalizations in patients with PH are associated with a high risk of mortality, pulmonary edema, peripartum cardiomyopathy, venous thromboembolism, arrhythmias, acute kidney injury, preeclampsia/eclampsia, and acute coronary syndrome.

A review regarding the article 'Effectiveness of mechanical circulatory support devices in reversing pulmonary hypertension among heart transplant candidates: A systematic review.'

Pulmonary hypertension (PH) with high pulmonary vascular resistance (PVR) is a very often diagnosed contraindication for orthotopic heart transplantation (OHT). It is a direct consequence of left ventricle failure characterized by high diastolic pressure obstructing the collection of blood from the pulmonary vessels. The occurrence of this situation grows with the increasing time of waiting for OHT, and with the progression of heart failure. Mechanical circulatory support (MCS) devices, particularly left ventricular assist devices (LVADs), have emerged as pivotal interventions for patients with fixed PH, offering a potential bridge to transplantation. The pathophysiological impact of PH in heart transplant candidates is profound, as it is associated with increased perioperative risk and heightened mortality post-transplantation. The selection of heart transplant candidates thus mandates a careful evaluation of PH, with an emphasis on distinguishing between reversible and fixed forms of the condition. Reversible PH can often be managed with medical therapies; however, fixed PH presents a more daunting challenge, necessitating more aggressive interventions like MCS. Patients are supported with LVADs until evidence of pulmonary afterload reversal is evident and then can be considered for heart transplantation. However, in those who are non-responders or have complications while being supported, their option for transplant is revoked. Despite these advancements, the heterogeneity of MCS devices and their mechanisms of action necessitates a nuanced understanding of their efficacy.

Obstructive Sleep Apnea, Obesity Hypoventilation Syndrome, and Pulmonary Hypertension: A State-of-the-Art Review.

The pathophysiological interplay between sleep-disordered breathing (SDB) and pulmonary hypertension (PH) is complex and can involve a variety of mechanisms by which SDB can worsen PH. These mechanistic pathways include wide swings in intrathoracic pressure while breathing against an occluded upper airway, intermittent and/or sustained hypoxemia, acute and/or chronic hypercapnia, and obesity. In this review, we discuss how the downstream consequences of SDB can adversely impact PH, the challenges in accurately diagnosing and classifying PH in the severely obese, and review the limited literature assessing the effect of treating obesity, obstructive sleep apnea, and obesity hypoventilation syndrome on PH.

[Consensus on the procedure of balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension].

Chronic thromboembolic pulmonary hypertension (CTEPH) is classified as group IV pulmonary hypertension, characterized by thrombotic occlusion of the pulmonary arteries leading to vascular stenosis or obstruction, progressive increase in pulmonary vascular resistance and pulmonary arterial pressure, and eventual right heart failure. Unlike other types of pulmonary hypertension, the prognosis of CTEPH can be significantly improved by surgery, vascular intervention, and/or targeted drug therapy. Pulmonary endarterectomy (PEA) is the preferred treatment of choice for CTEPH. However, PEA is an invasive procedure with high operative risks, and is currently only performed in a few centers in China. Balloon pulmonary angioplasty (BPA) is an emerging interventional technique for CTEPH, serving as an alternative for patients who are ineligible for PEA or with residual pulmonary hypertension after PEA. BPA is gaining traction in China, but its widespread adoption is limited due to its complexity, operator skills, and equipment requirements, a lack of standard operating procedures and technical guidance, which limit the further improvement and development of BPA in China. To address this, a multidisciplinary panel of experts was convened to develop the Consensus on the Procedure of Balloon Pulmonary Angioplasty for the Chronic Thromboembolic Pulmonary Hypertension, which fomulates guidelines on BPA procedural qualification, perioperative management, procedural planning, technical approach, and complication prevention, with the aim of providing recommendations and clinical guidance for BPA treatment in CTEPH and standardizing its clinical application in this setting. Summary of recommendations: Recommendation 1: It is recommended that physicians who specialize in pulmonary vascular diseases take the lead in formulating the diagnostic and treatment plans for CTEPH, using a multidisciplinary approach.Recommendation 2: Training in BPA technique is critical; novice operators should undergo standardized operative training with at least 50 procedures under the guidance of experienced physicians before embarking on independent BPA procedures.Recommendation 3: BPA requires catheterization labs, angiography systems, standard vascular interventional devices and consumables, drugs, and emergency equipment.Recommendation 4: Patient selection for BPA should consider cardiac and pulmonary function, coagulation status, and comorbid conditions to determine indications and contraindications, thereby optimizing the timing of the procedure and improving safety.Recommendation 5: In experienced centers, patients deemed likely to benefit from early BPA, based on clinical and imaging features of CTEPH and without elevated D-dimer levels, could bypass standard 3-month anticoagulation therapy.Recommendation 6: BPA is a complex interventional treatment that requires thorough pre-operative assessment and preparation.Recommendation 7: The use of perioperative anticoagulants in BPA requires a comprehensive risk assessment of intraoperative bleeding by the operator for individualized decision making.Recommendation 8: A variety of venous access routes are available for BPA; unless contraindicated, the right femoral vein is usually preferred because of its procedural convenience and reduced radiation exposure.Recommendation 9: For the different types of vascular lesion in CTEPH, treatment of ring-like stenoses, web-like lesions, and subtotal occlusions should be prioritized before addressing complete occlusions and tortuous lesions, in order to reduce complications and improve procedural safety.Recommendation 10: A targeted, incremental balloon dilatation strategy based on vascular lesions is recommended for BPA.Recommendation 11: Intravascular pulmonary artery imaging technologies, such as OCT and IVUS can assist in accurate vessel sizing and confirmation of wire placement in the true vascular lumen. Pressure wires can be used to objectively assess the efficacy of dilatation during BPA.Recommendation 12: Endpoints for BPA treatment should be individually assessed, taking into account improvements in clinical symptoms, hemodynamics, exercise tolerance, and quality of life.Recommendation 13: Post-BPA routine monitoring of vital signs is essential; anticoagulation therapy should be initiated promptly post-procedure in the absence of complications. In cases of intraoperative hemoptysis, postoperative anticoagulation regimen adjustments should be adjusted according to the bleeding severity.Recommendation 14: If reperfusion pulmonary edema occurs during or after BPA, ensure adequate oxygenation, diuresis, and consider non-invasive positive-pressure ventilation if necessary, while severe cases may require early mechanical ventilation assistance or ECMO.Recommendation 15: In cases of intraoperative hemoptysis, temporary balloon occlusion to stop bleeding is recommended, along with protamine to neutralize heparin. Persistent bleeding may warrant the use of gelatin sponges, coil embolization, or covered stent implantation.Recommendation 16: For contrast imaging during BPA, non-ionic, low or iso-osmolar contrast agents are recommended, with hydration status determined by the patient's clinical condition, cardiac and renal function, and intraoperative contrast volume used.