Forms Of Pulmonary Hypertension Research Articles

Abstract 4118959: Pulmonary Artery-Targeted Metformin-Loaded Nanocapsules Enhance Treatment of Pulmonary Arterial Hypertension

Background: Pulmonary arterial hypertension (PAH) remains a therapeutic challenge despite the availability of various medications. Metformin can be able to treat PAH but is associated with significant side effects. This study aims to enhance the efficacy and safety of metformin through a novel drug delivery system using low-dose metformin encapsulated in pulmonary artery-targeted nanocapsules. Methods: Metformin-loaded lung-targeted nanocapsules (MET nanocapsules) were synthesized using a specific lipid composition, including cationic lipids. The uptake and effects on cell viability were assessed in human pulmonary arterial smooth muscle cells (hPASMCs) from both healthy individuals and PAH patients. The therapeutic efficacy of MET nanocapsules was evaluated in a rat model of PAH. Safety was confirmed via serum biochemical tests in rats. Results: MET nanocapsules were successfully synthesized and demonstrated significant inhibition of PASMC proliferation. In the PAH rat model, MET nanocapsule treatment led to improved hemodynamic parameters, reduced right ventricular hypertrophy, and decreased pulmonary arterial medial thickening. Importantly, MET nanocapsules showed effective accumulation in the lungs of PAH rats. Conclusions: Intravenous administration of MET nanocapsules represents a safe and innovative therapeutic approach for PAH. This targeted delivery system has the potential to improve treatment outcomes while minimizing side effects and may have broader applications for other forms of pulmonary hypertension.

Long-standing response to calcium channel blocker therapy on patients with various types of pulmonary hypertension: a systematic review and meta analysis

Abstract Background It is widely acknowledged that the extended use of calcium channel blocker (CCBs) therapy in patients diagnosed with Idiopathic Pulmonary Arterial Hypertension (IPAH), Heritable Pulmonary Arterial Hypertension (HPAH), or Drug- or Toxin-Associated Pulmonary Arterial Hypertension (DPAH) who exhibit a positive acute vasoreactivity test (VdT+) provides benefits to patients. However, this practice is supported by a limited body of evidence in the scientific literature, mainly derived from expert consensus and/or small-scale studies, retrospective analyses, and registries, as per the European Society of Cardiology (ESC) guidelines. Objectives We performed a meta-analysis to evaluate the long-standing response to CCBs in patients diagnosed with various forms of pulmonary hypertension. Design We conducted searches in PubMed, Embase, and Cochrane to select both randomised and non-randomised studies. The primary outcomes of interest identified were Mean Pulmonary Artery Pressure (mPAP), 6-minute walk distance (6MWD), Cardiac Index (CI), Mean Right Atrial Pressure (mRAP), and Mixed venous oxygen saturation (SvO₂) measured at the beginning and end of the studies. Additionally, we performed subgroup analyses for all outcomes based on age groups: ≤18 years and >18 years. Statistical analysis was carried out using OpenMeta[Analyst] 12.11.14, and heterogeneity was assessed using I² statistics. Results We identified 7 non-randomised studies comprising a total of 131 patients with an average follow-up duration of 2.74 (1.3) years. The following are the mean values observed for individual outcomes: mPAP (33.1 mmHg; 95% CI [31.6, 34.6]; p < 0.001; I²=0%), 6MWD (470.1 m; 95% CI [452.6, 487.7]; I²=0%), Cardiac index (3.8 L/min/m²; 95% CI [3.6, 4.0]; I²=0%), mRAP (4.2 mmHg; 95% CI [3.6, 4.8]; I²=0%) and SvO₂ (73.9%; 95% CI [72.5, 75.3]; I²=0%) in patients with positive acute vasoreactivity test (VdT+) treated long-term with CCBs. Additionally, at study initiation, we found the following means: mPAP (51.2 mmHg; 95% CI [49.3, 53.0]; I²=0%), 6MWD (428.4 m; 95% CI [410.3, 446.6]; I²=0%), Cardiac index (2.8 L/min/m²; 95% CI [2.7, 2.9]; I²=0%), mRAP (6.4 mmHg; 95% CI [5.6, 7.2]; I²=0%), and SvO₂ (68.5%; 95% CI [66.5, 70.5]; I²=0%). Conclusion The findings from this meta-analysis suggest that in VdT+ patients, the means of certain haemodynamic parameters with long-standing use of CCBs are similar or nearly similar to those of patients without any subtype of PAH. These results align with current guidelines and reinforce their level of evidence.

Efficacy and safety of the Aria pulmonary endovascular device in pulmonary hypertension

Abstract Background and aims A common feature of various forms of pulmonary hypertension (PH) is progressive decline of pulmonary arterial compliance (CPA), which correlates with reduced survival. In this acute study, we evaluated feasibility, safety and hemodynamic performance of the Aria pulmonary endovascular device in patients with PH associated with left heart disease (PH-LHD) and chronic lung disease (PH-CLD). Methods 8 patients with PH-LHD and 10 patients with PH-CLD were included in this study. The device was placed in the main pulmonary artery via the right femoral vein and was connected by a catheter to a gas-filled reservoir outside the body. During systole, gas shifts from the balloon to the reservoir, leading to deflation of the balloon. In diastole, the gas returns from the reservoir to the balloon, leading to balloon inflation and enhancing diastolic blood flow to the distal pulmonary capillary bed. Hemodynamics were assessed at baseline, and again with device off, device on and device off. The primary safety endpoint was the incidence of serious adverse events through 30 days after the procedure. Results No complications or investigational device-related serious adverse events occurred. Device activation in PH-LHD and PH-CLD patients decreased pulmonary arterial pulse pressure by 5.6±4.2mmHg (-12%; p=0.003) and 4.2±2.2mmHg (-11%; p<0.001), increased CPA by 0.4±0.2mL/mmHg (+23%; p=0.004) and 0.4±0.3mL/mmHg (+25%; p=0.001), and increased RV-PV coupling by 0.24±0.18 (+40%; p=0.012) and 0.11±0.07 (+21%; p=0.001), respectively. Conclusions Temporary implantation of the Aria endovascular device was feasible and safe. Device activation resulted in acute improvement of CPA and RV-PV coupling.Figure

Relationship of TAPSE Normalized by Right Ventricular Area With Pulmonary Compliance, Exercise Capacity, and Clinical Outcomes.

While tricuspid annular plane systolic excursion (TAPSE) captures the predominant longitudinal motion of the right ventricle (RV), it does not account for ventricular morphology and radial motion changes in various forms of pulmonary hypertension. This study aims to account for both longitudinal and radial motions by dividing TAPSE by RV area and to assess its clinical significance. We performed a retrospective analysis of 71 subjects with New York Heart Association class II to III dyspnea who underwent echocardiogram and invasive cardiopulmonary exercise testing (which defined 4 hemodynamic groups: control, isolated postcapillary pulmonary hypertension, combined postcapillary pulmonary hypertension, and pulmonary arterial hypertension). On the echocardiogram, TAPSE was divided by RV area in diastole (TAPSE/RVA-D) and systole (TAPSE/RVA-S). Analyses included correlations (Pearson and linear regression), receiver operating characteristic, and survival curves. On linear regression analysis, TAPSE/RVA metrics (versus TAPSE) had a stronger correlation with pulmonary artery compliance (r=0.48-0.54 versus 0.38) and peak VO2 percentage predicted (0.23-0.30 versus 0.18). Based on the receiver operating characteristic analysis, pulmonary artery compliance ≥3 mL/mm Hg was identified by TAPSE/RVA-D with an under the curve (AUC) of 0.79 (optimal cutoff ≥1.1) and by TAPSE/RVA-S with an AUC of 0.83 (optimal cutoff ≥1.5), but by TAPSE with only an AUC of 0.67. Similarly, to identify peak VO2 <50% predicted, AUC of 0.66 for TAPSE/RVA-D and AUC of 0.65 for TAPSE/RVA-S. Death or cardiovascular hospitalization at 12 months was associated with TAPSE/RVA-D ≥1.1 (HR, 0.38 [95% CI, 0.11-0.56]) and TAPSE/RVA-S ≥1.5 (HR, 0.44 [95% CI, 0.16-0.78]), while TAPSE was not associated with adverse outcomes (HR, 0.99 [95% CI, 0.53-1.94]). Among 31 subjects with available cardiac magnetic resonance imaging, RV ejection fraction was better correlated with novel metrics (TAPSE/RVA-D r=0.378 and TAPSE/RVA-S r=0.328) than TAPSE (r=0.082). In a broad cohort with suspected pulmonary hypertension, TAPSE divided by RV area was superior to TAPSE alone in correlations with pulmonary compliance and exercise capacity. As a prognostic marker of right heart function, TAPSE/RVA-D <1.1 and TAPSE/RVA-S <1.5 predicted adverse cardiovascular outcomes.

Efficacy and safety of the Aria pulmonary endovascular device in pulmonary hypertension.

A common feature of various forms of pulmonary hypertension (PH) is progressive decline of pulmonary arterial compliance (CPA), which correlates with reduced survival. In this acute study, we evaluated feasibility, safety and haemodynamic performance of the Aria pulmonary endovascular device in patients with PH associated with left heart disease (PH-LHD) and chronic lung disease (PH-CLD). Eight patients with PH-LHD and 10 patients with PH-CLD were included in this study. The device was placed in the main pulmonary artery via the right femoral vein and was connected by a catheter to a gas-filled reservoir outside the body. During systole, gas shifts from the balloon to the reservoir, leading to deflation of the balloon. In diastole, the gas returns from the reservoir to the balloon, leading to balloon inflation and enhancing diastolic blood flow to the distal pulmonary capillary bed. Haemodynamics were assessed at baseline, and again with device off, device on and device off. The primary safety endpoint was the incidence of serious adverse events through 30 days after the procedure. No complications or investigational device-related serious adverse events occurred. Device activation in PH-LHD and PH-CLD patients decreased pulmonary arterial pulse pressure by 5.6 ± 4.2 mmHg (-12%; p = 0.003) and 4.2 ± 2.2 mmHg (-11%; p < 0.001), increased CPA by 0.4 ± 0.2 ml/mmHg (+23%; p = 0.004) and 0.4 ± 0.3 ml/mmHg (+25%; p = 0.001), and increased right ventricular-to-pulmonary vascular (RV-PV) coupling by 0.24 ± 0.18 (+40%; p = 0.012) and 0.11 ± 0.07 (+21%; p = 0.001), respectively. Temporary implantation of the Aria endovascular device was feasible and safe. Device activation resulted in acute improvement of CPA and RV-PV coupling.

Health-Related Quality of Life Across the Spectrum of Pulmonary Hypertension

BackgroundHealth related quality of life (HRQOL) is frequently impaired in pulmonary arterial hypertension (PAH). However, little is known about HRQOL in other forms of pulmonary hypertension (PH). Research QuestionDoes HRQOL vary across groups of the World Symposium on Pulmonary Hypertension (WSPH) classification system? Study Design and MethodsThis cross-sectional study included PH patients from PVDOMICS (Pulmonary Vascular Disease Phenomics). HRQOL was assessed using emPHasis-10 (e-10), Medical Outcomes Survey Short Form-36 (SF-36; physical component (PCS) and mental component (MCS)), and Minnesota Living with Heart Failure Questionnaire (MLHF). Pearson’s correlations between HRQOL and demographic, physiologic, and imaging characteristics within each WSPH group were tested. Multivariable linear regressions compared HRQOL across WSPH groups adjusting for demographics, disease prevalence, functional class, and hemodynamics. Cox proportional hazard models were used to assess associations between HRQOL and survival across WSPH groups. ResultsAmong 691 PH patients, HRQOL correlated with functional class and six-minute walk distance but not hemodynamics. HRQOL was severely depressed across WSPH groups for all measures except the SF-36 MCS. When compared to Group 1, Group 2 subjects had significantly worse HRQOL (e-10: 29 vs 24, p=0.001, PCS: 32.9 ± 8 vs 38.4 ± 10, p<0.0001, MLHF: 50 vs 38, p=0.003). Group 3 subjects similarly had worse e-10 (31 vs 24, p<0.0001) and PCS scores (33.3 ± 9 vs 38.4 ± 10, p<0.0001) compared to Group 1, which persisted in multivariable models (p<0.05). HRQOL was associated in adjusted models with survival across Groups 1, 2, and 3. InterpretationHRQOL is depressed in PH and particularly in Groups 2 and 3 despite less severe hemodynamics. HRQOL is associated with functional capacity, but hemodynamic disease severity poorly estimates the impact of PH on patient’s lives. Further studies are needed to better identify predictors and treatments to improve HRQOL across the spectrum of pulmonary hypertension.

Transcriptional profiles of pulmonary artery endothelial cells in pulmonary hypertension

Pulmonary arterial hypertension (PAH) is characterized by endothelial cell (EC) dysfunction. There are no data from living patients to inform whether differential gene expression of pulmonary artery ECs (PAECs) can discern disease subtypes, progression and pathogenesis. We aimed to further validate our previously described method to propagate ECs from right heart catheter (RHC) balloon tips and to perform additional PAEC phenotyping. We performed bulk RNA sequencing of PAECs from RHC balloons. Using unsupervised dimensionality reduction and clustering we compared transcriptional signatures from PAH to controls and other forms of pulmonary hypertension. Select PAEC samples underwent single cell and population growth characterization and anoikis quantification. Fifty-four specimens were analyzed from 49 subjects. The transcriptome appeared stable over limited passages. Six genes involved in sex steroid signaling, metabolism, and oncogenesis were significantly upregulated in PAH subjects as compared to controls. Genes regulating BMP and Wnt signaling, oxidative stress and cellular metabolism were differentially expressed in PAH subjects. Changes in gene expression tracked with clinical events in PAH subjects with serial samples over time. Functional assays demonstrated enhanced replication competency and anoikis resistance. Our findings recapitulate fundamental biological processes of PAH and provide new evidence of a cancer-like phenotype in ECs from the central vasculature of PAH patients. This “cell biopsy” method may provide insight into patient and lung EC heterogeneity to advance precision medicine approaches in PAH.

Identification of Ferroptosis-related potential biomarkers and immunocyte characteristics in Chronic Thromboembolic Pulmonary Hypertension via bioinformatics analysis

BackgroundChronic Thromboembolic Pulmonary Hypertension (CTEPH) is a form of pulmonary hypertension with a high mortality rate. A new type of iron-mediated cell death is Ferroptosis, which is characterized by the accumulation of lethal iron ions and lipid peroxidation leading to mitochondrial atrophy and increased mitochondrial membrane density. Now, there is a lack of Ferroptosis-related biomarkers (FRBs) associated with pathogenic process of CTEPH.MethodsThe differentially expressed genes (DEGs) of CTEPH were obtained by GEO2R. Genes related to Ferroptosis were obtained from FerrDb database. The intersection of Ferroptosis and DEGs results in FRBs. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were performed in Database for Annotation, Visualization and Integrated Discovery (DAVID) database. The optimal potential biomarkers for CTEPH were analyzed by least absolute shrinkage and selection operator (LASSO) and support vector machine-recursive feature elimination (SVM-RFE) machine learning. The four hub genes were verified from the Gene Expression Omnibus (GEO) dataset GSE188938. Immune infiltration was analyzed by CIBERSORT. SPSS software was used to analyze the Spearman rank correlation between FRBs identified and infiltration-related immune cells, and p < 0.05 was considered as statistically significant.ResultsIn this study, potential genetic biomarkers associated with Ferroptosis in CTEPH were investigated and explored their role in immune infiltration. In total, we identified 17 differentially expressed Ferroptosis-associated genes by GEOquery package. The key FRBs including ARRDC3, HMOX1, BRD4, and YWHAE were screened using Lasso and SVM-RFE machine learning methods.Through gene set GSE188938 verification, only upregulation of gene ARRDC3 showed statistical difference. In addition, immune infiltration analysis using the CIBERSORT algorithm revealed the infiltration of Eosinophils and Neutrophils in CTEPH samples was less than that in the control group. And correlation analysis revealed that ARRDC3 was positively correlated with T cells follicular helper (r = 0.554, p = 0.017) and negatively correlated with Neutrophils (r = -0.47, p = 0.049).ConclusionsIn conclusion, ARRDC3 upregulation with different immune cell infiltration were involved in the development of CTEPH. ARRDC3 might a potential Ferroptosis-related biomarker for CTEPH treatment. This study provided a new insight into pathogenesis CTEPH.

Connective tissue disease-associated pulmonary hypertension: A comprehensive review.

Connective tissue diseases (CTDs) can be associated with various forms of pulmonary hypertension, including pulmonary arterial hypertension (PAH), pulmonary veno-occlusive disease, pulmonary venous hypertension, interstitial lung disease-associated pulmonary hypertension, chronic thromboembolic pulmonary hypertension, and sometimes a combination of several processes. The prevalence of PAH varies among the different CTDs, with systemic sclerosis (SSc) having the highest at 8%-12%. The most recent European Society of Cardiology/European Respiratory Societyguidelines recommend routine annual screening for PAH in SSc and CTDs with SSc features. As CTDs can be associated with a myriad of presentations of pulmonary hypertension, a thorough evaluation to include a right heart catheterization to clearly delineate the hemodynamic profile is essential in developing an appropriate treatment plan. Treatment strategies will depend on the predominant phenotype of pulmonary vasculopathy. In general, management approach to CTD-PAH mirrors that of idiopathic PAH. Despite this, outcomes of CTD-PAH are inferior to those of idiopathic PAH, with those of SSc-PAH being particularly poor. Reasons for this may include extrapulmonary manifestations of CTDs, including renal disease and gastrointestinal involvement, concurrent interstitial lung disease, and differences in the innate response of the right ventricle to increased pulmonary vascular resistance. Early referral for lung transplant evaluation of patients with CTD-PAH, particularly SSc-PAH, is recommended. It is hoped that in the near future, additional therapies may be added to the armamentarium of effective treatments for CTD-PAH. Ultimately, a better understanding of the pathogenesis of CTD-PAH will be required to develop targeted therapies for this morbid condition.

Transcriptional profiling unveils molecular subgroups of adaptive and maladaptive right ventricular remodeling in pulmonary hypertension

Right ventricular (RV) function is critical to prognosis in all forms of pulmonary hypertension. Here we perform molecular phenotyping of RV remodeling by transcriptome analysis of RV tissue obtained from 40 individuals, and two animal models of RV dysfunction of both sexes. Our unsupervised clustering analysis identified ‘early’ and ‘late’ subgroups within compensated and decompensated states, characterized by the expression of distinct signaling pathways, while fatty acid metabolism and estrogen response appeared to underlie sex-specific differences in RV adaptation. The circulating levels of several extracellular matrix proteins deregulated in decompensated RV subgroups were assessed in two independent cohorts of individuals with pulmonary arterial hypertension, revealing that NID1, C1QTNF1 and CRTAC1 predicted the development of a maladaptive RV state, as defined by magnetic resonance imaging parameters, and were associated with worse clinical outcomes. Our study provides a resource for subphenotyping RV states, identifying state-specific biomarkers, and potential therapeutic targets for RV dysfunction.

Moderate hypoxia induces metabolic divergence in circulating monocytes and tissue resident macrophages from Berkeley sickle cell anemia mice.

Human and murine sickle cell disease (SCD) associated pulmonary hypertension (PH) is defined by hemolysis, nitric oxide depletion, inflammation, and thrombosis. Further, hemoglobin (Hb), heme, and iron accumulation are consistently observed in pulmonary adventitial macrophages at autopsy and in hypoxia driven rodent models of SCD, which show distribution of ferric and ferrous Hb as well as HO-1 and ferritin heavy chain. The anatomic localization of these macrophages is consistent with areas of significant vascular remodeling. However, their contributions toward progressive disease may include unique, but also common mechanisms, that overlap with idiopathic and other forms of pulmonary hypertension. These processes likely extend to the vasculature of other organs that are consistently impaired in advanced SCD. To date, limited information is available on the metabolism of macrophages or monocytes isolated from lung, spleen, and peripheral blood in humans or murine models of SCD. Here we hypothesize that metabolism of macrophages and monocytes isolated from this triad of tissue differs between Berkley SCD mice exposed for ten weeks to moderate hypobaric hypoxia (simulated 8,000 ft, 15.4% O2) or normoxia (Denver altitude, 5000 ft) with normoxia exposed wild type mice evaluated as controls. This study represents an initial set of data that describes the metabolism in monocytes and macrophages isolated from moderately hypoxic SCD mice peripheral lung, spleen, and blood mononuclear cells.

Nailfold capillaroscopy and candidate-biomarker levels in systemic sclerosis-associated pulmonary hypertension: A cross-sectional study.

Pulmonary hypertension is one of the leading causes of death in systemic sclerosis. Early detection and treatment of pulmonary hypertension in systemic sclerosis is crucial. Nailfold capillaroscopy microscopy, vascular autoantibodies AT1R and ETAR, and several candidate-biomarkers have the potential to serve as noninvasive tools to identify systemic sclerosis patients at risk for developing pulmonary hypertension. Here, we explore the classifying potential of nailfold capillaroscopy microscopy characteristics and serum levels of selected candidate-biomarkers in a sample of systemic sclerosis patients with and without different forms of pulmonary hypertension. A total of 81 consecutive systemic sclerosis patients were included, 40 with systemic sclerosis pulmonary hypertension and 41 with no pulmonary hypertension. In each group, quantitative and qualitative nailfold capillaroscopy microscopy characteristics, vascular autoantibodies AT1R and ETAR, and serum levels of 24 soluble serum factors were determined. For evaluation of the nailfold capillaroscopy microscopy characteristics, linear regression analysis accounting for age, sex, and diffusing capacity of the lungs for carbon monoxide percentage predicted was used. Autoantibodies and soluble serum factor levels were compared using two-sample t test with equal variances. No statistically significant differences were observed in quantitative or qualitative nailfold capillaroscopy microscopy characteristics, or vascular autoantibody ETAR and AT1R titer between systemic sclerosis-pulmonary hypertension and systemic sclerosis-no pulmonary hypertension. In contrast, several serum levels of soluble factors differed between groups: Endostatin, sVCAM, and VEGFD were increased, and CXCL4, sVEGFR2, and PDGF-AB/BB were decreased in systemic sclerosis-pulmonary hypertension. Random forest classification identified Endostatin and CXCL4 as the most predictive classifiers to distinguish systemic sclerosispulmonary hypertension from systemic sclerosis-no pulmonary hypertension. This study shows the potential for several soluble serum factors to distinguish systemic sclerosis-pulmonary hypertension from systemic sclerosis-no pulmonary hypertension. We found no classifying potential for qualitative or quantitative nailfold capillaroscopy microscopy characteristics, or vascular autoantibodies.

Pulmonary artery compliance in different forms of pulmonary hypertension

ObjectivePulmonary artery compliance (PAC), estimated as stroke volume (SV) divided by pulmonary artery pulse pressure (PP), may be a predictor of survival in pulmonary arterial hypertension (PAH). Resistance–compliance (RC) time,...

Multidisciplinary Approach to Chronic Thromboembolic Pulmonary Hypertension: Role of Radiologists

Management of chronic thromboembolic pulmonary hypertension (CTEPH) should be determined by a multidisciplinary team, ideally at a specialized CTEPH referral center. Radiologists contribute to this multidisciplinary process by helping to confirm the diagnosis of CTEPH and delineating the extent of disease, both of which help determine a treatment decision. Preoperative assessment of CTEPH usually employs multiple imaging modalities, including ventilation-perfusion (V/Q) scanning, echocardiography, CT pulmonary angiography (CTPA), and right heart catheterization with pulmonary angiography. Accurate diagnosis or exclusion of CTEPH at imaging is imperative, as this remains the only form of pulmonary hypertension that is curative with surgery. Unfortunately, CTEPH is often misdiagnosed at CTPA, which can be due to technical factors, patient-related factors, radiologist-related factors, as well as a host of disease mimics including acute pulmonary embolism, in situ thrombus, vasculitis, pulmonary artery sarcoma, and fibrosing mediastinitis. Although V/Q scanning is thought to be substantially more sensitive for CTEPH compared with CTPA, this is likely due to lack of recognition of CTEPH findings rather than a modality limitation. Preoperative evaluation for pulmonary thromboendarterectomy (PTE) includes assessment of technical operability and surgical risk stratification. While the definitive therapy for CTEPH is PTE, other minimally invasive or noninvasive therapies also lead to clinical improvements including greater survival. Complications of PTE that can be identified at postoperative imaging include infection, reperfusion edema or injury, pulmonary hemorrhage, pericardial effusion or hemopericardium, and rethrombosis. ©RSNA, 2022 Online supplemental material is available for this article.

Clinical phenotyping of plasma thrombospondin-2 reveals relationship to right ventricular structure and function in pulmonary hypertension.

Converging evidence from proteogenomic analyses prioritises thrombospondin-2 (TSP2) as a potential biomarker for idiopathic or heritable pulmonary arterial hypertension (PAH). We aimed to assess TSP2 levels in different forms of pulmonary hypertension (PH) and to define its clinical phenotype. Absolute concentrations of TSP2 were quantified in plasma samples from a prospective single-centre cohort study including 196 patients with different forms of PH and 16 disease controls (suspected PH, but normal resting pulmonary haemodynamics). In an unbiased approach, TSP2 levels were related to 152 clinical variables. Concentrations of TSP2 were increased in patients with PH versus disease controls (p<0.001 for group comparison). The discriminatory ability of TSP2 levels to distinguish between patients and controls was superior to that of N-terminal pro-brain natriuretic peptide (p=0.0023 for comparison of areas under the curve). Elevation of TSP2 levels was consistently found in subcategories of PAH, in PH due to lung disease and due to left heart disease. Phenotypically, TSP2 levels were robustly related to echocardiographic markers that indicate the right ventricular (RV) response to chronically increased afterload with increased levels in patients with impaired systolic function and ventriculoarterial uncoupling. Focusing on PAH, increased TSP2 levels were able to distinguish between adaptive and maladaptive RV phenotypes (area under the curve 0.87, 95% CI 0.76-0.98). The study indicates that plasma TSP2 levels inform on the presence of PH and associate with clinically relevant RV phenotypes in the setting of increased afterload, which may provide insight into processes of RV adaptability.

Immune cell-derived serine protease as pathogenic drivers of vascular remodeling in pulmonary arterial hypertension

In recent years, accumulating evidence has shown that pulmonary arterial hypertension (PAH) has a strong underlying inflammatory component. Vascular remodeling, a common pathology observed in all forms of pulmonary hypertension (PH), is accompanied by a pronounced accumulation of leukocytes around and within the vessels. Proteolytic products of immune cells, particularly neutrophil and mast cell serine proteases, have been shown to play a central pathogenic role in vascular remodeling and PAH development. Serine proteases are involved in many aspects of the inflammatory response, such as extracellular matrix degradation, regulation of bioavailability of cytokines, chemokines, and growth factors, and dysregulation of their activity can have devastating consequences. In this review, we will focus on immune dysregulation in PAH and shed light on the pro-inflammatory role of serine proteases in vascular pathology observed in the context of this disease.

Chronic thromboembolic pulmonary hypertension resulting in decompensated right heart failure

Chronic thromboembolic pulmonary hypertension is a notoriously underdiagnosed cause of severe pulmonary hypertension. It is a form of precapillary pulmonary hypertension (PH) that results from intraluminal thrombus organization and fibrous formation which ultimately results in the complete obliteration of pulmonary arteries, resulting in increased pulmonary vascular resistance which leads to the development of pulmonary hypertension and as a result right heart failure. The mechanism involves the narrowing of the pulmonary artery which increases blood pressure within the lungs and impairs blood flow which increases the workload of the right side of the heart ultimately causing right heart failure. Pulmonary hypertension can also cause arrhythmias, blood clots, and bleeding in the lungs. Even though CTEPH is a deadly condition, among all forms of pulmonary hypertension, CTEPH is the only curable form. Echocardiography is the initial assessment tool for suspected PH. A right heart catheterization may be performed to confirm the presence of pulmonary hypertension. Confirmation of CTEPH requires a V/Q scan. Although ventilation/perfusion scintigraphy has a major role in the evaluation of patients with suspected CTEPH, nowadays CTA chest is being used widely as it produces much better-quality images compared to V/Q scan. Without treatment, the prognosis is very poor. Out of three treatment modalities such as; pulmonary endarterectomy (PEA) surgery, balloon pulmonary angioplasty (BPA), and medical therapy, surgery is the gold standard. The physician must be familiar with the disease entity, early diagnosis, and appropriate treatment to improve survival. Here we present a literature review on this topic.

Investigating monotherapy and combination therapy trends in newly diagnosed patients with pulmonary arterial hypertension among EU3 &amp; UK physicians over the COVID-19 pandemic

Abstract Background Pulmonary Arterial Hypertension (PAH) is a form of pulmonary hypertension, where the narrowing of arteries in the lungs restricts blood flow and so increases pressure in the vessels. Studies have demonstrated that initial combination therapies are optimal for PAH management. However, prescription of monotherapy treatment is still prevalent as a first line therapy. Purpose The purpose of this research was to investigate prescribing trends of physicians for first line patients with PAH in the UK, Germany, Italy and Spain. We investigated the proportions of newly diagnosed patients and the prescription trends for monotherapy and combination therapy prior to and during the COVID-19 pandemic. Methods A multi-country, multi-centre online medical chart review study of patients with PAH was conducted between April – June of 2019, 2020 and 2021 respectively. Recruited from a large access panel, 178 treating cardiologists, pulmonologists &amp; rheumatologists in the UK (n=16), Germany (n=55), Italy (n=55) and Spain (n=52) were screened for duration of practice in their speciality and caseload (≥5 PAH patients in the last 3 months), and provided data on 694 PAH patients (UK = 71, Germany = 206, Italy = 208, Spain = 209). Reported patient data pertained to medical chart information reflecting the prior year, i.e., Q2 2021 data reflected the 2020 period (advent of the COVID-19 pandemic). Results In this dataset, there has been a consistent decrease in the proportion of newly diagnosed (i.e. diagnosed within 12 months of being reported) patients reported from 2019 to 2020 and 2021. In 2019, 49% of the reported patients were diagnosed within the last 12 months. However, the newly diagnosed patient population dropped to 37% in 2020 and continued to drop to 27% in 2021. Despite this, there has been an increase in reported first line patients within the newly diagnosed segment from 74% in 2019, to 75% in 2020, then at 87% in 2021. This increase can be seen to coincide with the ongoing COVID-19 pandemic. In 2019, 58% of reported newly diagnosed patients were recorded as receiving monotherapy. This did drop to 33% in 2020; however, in 2021 monotherapy uptake increased to 47%. Of note, the usage of the endothelin receptor antagonist (ERA) drug class increased from 67% in 2019 to 83% in 2020 but dropped to 69% in 2021. Conclusions This data set suggests a decreasing trend in newly diagnosed patients and a gradual shift in treatment type to first line monotherapy prescription, which coincided with the height of the COVID-19 pandemic. More newly diagnosed patients (those diagnosed within 12 months of being reported) are receiving monotherapy treatment at the expense of combination therapy, and this has also coincided with the pandemic. Further investigation using comparator cohort is warranted to assess whether the challenges physicians faced during the pandemic has had a causal effect on the prescribing habits for PAH therapies. Funding Acknowledgement Type of funding sources: None.

HMGB1 Upregulates RAGE to Trigger the Expression of Inflammatory Factors in the Lung Tissue in a Hypoxic Pulmonary Hypertension Rat Model.

Hypoxic pulmonary hypertension (HPH), a form of pulmonary hypertension (PH) caused by hypoxia, could cause serious complications and has a high mortality rate, and no clinically effective treatments are currently available. In this study, we established an HPH preclinical model in rats by simulating clinicopathological indicators of the disease. Our results showed that high mobility group box-1 protein (HMGB1) aggravated the clinical symptoms of HPH. We aimed at establishing protocols and ideas for the clinical treatment of HPH by identifying downstream HMGB1 binding receptors. Our investigation showed that continuous hypoxia could cause significant lung injury in rats. ELISA and western blotting experiments revealed that HPH induces inflammation in the lung tissue and increases the expression of a hypoxia-inducible factor. Testing of lung tissue proteins in vivo and in human pulmonary artery endothelial cells in vitro revealed that the HMGB1-mediated increase in the receptor for advanced glycation end products (RAGE) expression promoted inflammation. In summary, we successfully established an HPH rat model providing a new model for preclinical HPH research and elucidated the role of HMGB1 in HPH. Furthermore, we describe that HMGB1 induced inflammation in the HPH model via RAGE, causing severe lung dysfunction. This study could potentially provide novel ideas and methods for the clinical treatment of HPH.

Chronic thromboembolic pulmonary hypertension: A 10-year analysis from a Portuguese referral center

Introduction and ObjectivesChronic thromboembolic pulmonary hypertension (CTEPH) is a progressive, but potentially curable, form of pulmonary hypertension. Pulmonary endarterectomy (PEA) is a complex surgery that frequently achieves hemodynamic normalization and symptom resolution, although not all patients are suitable for the procedure. We aimed to assess long-term outcomes of CTEPH, namely all-cause mortality and hospital admission for decompensated heart failure, according to treatment modalities in patients who underwent PEA or non-surgical therapy. MethodsA 10-year retrospective study of patients with CTEPH at a referral center was conducted. Forty-five patients were included and median follow-up time was 57 (IQR 24-93) months. Survival analysis was performed and a multivariate Cox regression model was used to identify independent predictors of outcomes. ResultsPatients were mostly female (59%) and mean age was 63±16 years. Two-thirds were severely symptomatic at diagnosis, with 62.2% of patients presenting in WHO functional class (WHO FC) III or IV. One-, two- and three-year survival was 93.3%, 82.4% and 75.9%, respectively. Serum BNP (HR 1.003; 95% CI: 1.001-1.005; p=0.003) and creatinine (HR 12.092; 95% CI: 1.121-130.390; p=0.040) were predictors of death. Mortality was numerically lower in those who underwent PEA (p=0.135). PEA was associated with decreased risk of the combined endpoint of all-cause mortality and hospital admission for decompensated heart failure (HR 0.198; 95% CI: 0.040-0.982; p=0.047), as were lower serum BNP (HR 1.003; 95% CI: 1.001-1.005; p=0.008) and mPAP (HR 1.073; 95% CI: 1.022-1.128; p=0.005) at diagnosis. Most patients who underwent PEA presented improved WHO FC (92.9%) and post-surgical residual pulmonary hypertension was identified in only 21.4%. ConclusionPEA provided a better overall prognosis than non-surgical therapy, improving symptoms and frequently achieving hemodynamic normalization, with a numerical trend for lower mortality. Higher serum BNP, creatinine and mPAP at diagnosis were independently associated with worse outcomes.