A global view of pulmonary hypertension

Pulmonary Vascular Research Institute GoDeep: A meta-registry merging deep phenotyping datafrom international PH reference centers

The Pulmonary Vascular Research Institute GoDeep meta-registry is a collaboration of pulmonary hypertension (PH) reference centers across the globe. Merging worldwide PH data in a central meta-registry to allow advanced analysis of the heterogeneity of PH and its groups/subgroups on a worldwide geographical, ethnical, and etiological landscape (ClinTrial. gov NCT05329714). Retrospective and prospective PH patient data (diagnosis based on catheterization; individuals with exclusion of PH are included as a comparator group) are mapped to a common clinical parameter set of more than 350 items, anonymized and electronically exported to a central server. Use and access is decided by the GoDeep steering board, where each center has one vote. As of April 2022, GoDeep comprised 15,742 individuals with 1.9 million data points from eight PH centers. Geographic distribution comprises 3990 enrollees (25%) from America and 11,752 (75%) from Europe. Eighty-nine perecent were diagnosed with PH and 11% were classified as not PH and provided a comparator group. The retrospective observation period is an average of 3.5 years (standard error of the mean 0.04), with 1159 PH patients followed for over 10 years. Pulmonary arterial hypertension represents the largest PH group (42.6%), followed by Group 2 (21.7%), Group 3 (17.3%), Group 4 (15.2%), and Group 5 (3.3%). The age distribution spans several decades, with patients 60 years or older comprising 60%. The majority of patients met an intermediate risk profile upon diagnosis. Data entry from a further six centers is ongoing, and negotiations with >10 centers worldwide have commenced. Using electronic interface-based automated retrospective and prospective data transfer, GoDeep aims to provide in-depth epidemiological and etiological understanding of PH and its various groups/subgroups on a global scale, offering insights for improved management.

Plasma metabolomics in the perioperative period of defect repair in patients with pulmonary arterial hypertension associated with congenital heart disease

The quality of life and survival rates of patients with pulmonary arterial hypertension associated with congenital heart disease (CHD-PAH) have been greatly improved by defect-repair surgery and personalized treatments. However, those who survive surgery may remain at risk of persistent PAH, the prognosis may be considerably worse than those unoperated. Dynamic monitoring of clinical measures during the perioperative period of shunt correction is therefore indispensable and of great value. In this study, we explored the plasma-metabolite profiling in 13 patients with CHD-PAH during the perioperative period of defect repair. Plasma was harvested at four time points: prior to cardiopulmonary bypass (CPB) after anesthesia (Pre), immediately after CPB (T0), 24 h (T24), and 48 h (T48) after defect repair. Untargeted metabolomics strategy based on UPLC Q-TOF MS was used to detect the metabolites. A total of 193 distinguishing metabolites were determined at different time points, enriched in pathways such as oxidation of branched-chain fatty acids. We found that 17 metabolite alterations were significantly correlated with the reduction in mean pulmonary arterial pressure (MPAP) at T48 versus Pre. Gradients in diastolic pulmonary arterial pressure (DPAP), bicarbonate in radial artery (aHCO₃), bicarbonate in superior vena cava (svcHCO₃), and the partial pressure of dissolved CO₂ gas in radial artery (aPCO₂) were positively correlated with MPAP gradient. Notably, these clinical-measure gradients were correlated with alterations in shunt-correction-associated metabolites. In total, 12 out of 17 identified metabolites in response to defect repair were increased at both T24 and T48 (all P < 0.05, except propionylcarnitine with P < 0.05 at T24). In contrast, galactinol dihydrate, guanosine monophosphate, and hydroxyphenylacetylglycine tended to decline at T24 and T48 (only galactinol dihydrate with P < 0.05 at T48). In conclusion, 17 metabolites that respond to shunt correction could be used as suitable noninvasive markers, and clinical measures, including DPAP, aHCO₃, svcHCO₃, and aPCO₂, would be of great value in disease monitoring and evaluating future therapeutic interventions.

Management and prognosis of HIV-associated pulmonary arterial hypertension: 20 Years of evidence from the REHAP registry

BACKGROUND

Pulmonary arterial hypertension (PAH) is an independent predictor of death in patients with human immunodeficiency virus (HIV) infection. HIV is the leading cause of PAH (HIV-PAH) worldwide.

AIMS

We described the characteristics, treatment patterns, and prognosis of a cohort of HIV-PAH patients and compared them with those of an equivalent cohort of patients with idiopathic/familial PAH (IPAH/FPAH).

METHODS

We retrospectively analysed and compared the demographic, clinical, and treatment data from patients with HIV-PAH and those with IPAH/FPAH in the Spanish PAH registry (REHAP) from 1998 to 2018. The HIV-PAH overall survival (OS) rate up to 5 years was compared to the age- and sex-matched IPAH/FPAH population. Changes in treatment patterns in patients with HIV-PAH after 2010 and their effects on OS were also analysed.

RESULTS

Compared to those with IPAH/FPAH (n = 739), patients with HIV-PAH (n = 132) were younger, mainly men, and had a better functional status. The clinical presentation, haemodynamics, and respiratory function were similar between the groups. Parenteral drug use was the most common mode of HIV transmission. Approximately 11% of patients with HIV-PAH did not receive PAH-targeted therapy. The age- and sex-adjusted 5-year OS rate from diagnosis was 74.0% for patients with HIV-PAH and 68.7% for those with IPAH (p < 0.159). During/after 2010, 23% of patients with IPAH/FPAH received upfront dual oral combination, while oral monotherapy remained the main first-line treatment in patients with HIV-PAH. The overall OS rate remained stable.

CONCLUSIONS

Patients with HIV-PAH were predominantly young men. The short-term prognosis is similar to that of age- and sex-matched patients with IPAH/FPAH, despite a better functional status. Oral monotherapy remains the preferred first-line treatment in the current cohorts.

Potential Role of Cellular Senescence in Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a rare and chronic lung vasculature disease characterized by pulmonary vasculature remodeling, including abnormal proliferation of pulmonary artery smooth muscle cells (PASMCs) and dysfunctional endothelial cells (ECs). Remodeling of the pulmonary vasculature occurs from maturity to senescence, and it has become apparent that cellular senescence plays a central role in the pathogenesis of various degenerative vascular diseases and pulmonary pathologies. Cellular senescence represents a state of stable proliferative arrest accompanied by the senescence-associated secretory phenotype (SASP), which entails the copious secretion of proinflammatory signals in the tissue microenvironment. Evidences show that in PAH patients, higher levels of cytokines, chemokines, and inflammatory mediators can be detected and correlate with clinical outcome. Moreover, senescent cells accrue with age in epithelial, endothelial, fibroblastic, and immunological compartments within human lungs, and evidence showed that ECs and PASMCs in lungs from patients with chronic obstructive pulmonary disease were characterized by a higher number of senescent cells. However, there is little evidence uncovering the molecular pulmonary vasculature senescence in PAH. Herein, we review the cellular senescence in pulmonary vascular remodeling, and emphasize its importance in PAH. We further introduce some signaling pathways which might be involved in vasculature senescence and PAH, with the intent to discuss the possibility of the PAH therapy via targeting cellular senescence and reduce PAH progression and mortality.

The Incidence and Prevalence of Pulmonary Hypertension in the COPD Population: A Systematic Review and Meta-Analysis

Purpose

Chronic obstructive pulmonary disease (COPD)-related pulmonary hypertension (PH) is one of the most common comorbidities of COPD, and often leads to a worse prognosis. Although the estimated prevalence and risk factors of COPD-related PH have been widely reported, these results have not been well integrated. This study aimed to review the worldwide incidence and prevalence of COPD-related PH and explore possible factors affecting its prevalence.

Patients and Methods

We searched four electronic databases (Web of Science, Embase, Cochrane, and MEDLINE) to identify all observational studies on the prevalence of COPD-related PH from database creation until July 20, 2021. Eligibility screening, quality assessment, and data extraction of the retrieved studies were independently conducted by two reviewers. Meta-analyses were performed to determine the prevalence of PH in the COPD population. Random-effects meta-regression model analyses were conducted to investigate the sources of heterogeneity.

Results

Altogether, 38 articles were included in the meta-analyses. The pooled prevalence was 39.2% (95% CI: 34.0–44.4, I² = 97.6%) for COPD-related PH. Subgroup analyses showed that the prevalence of PH increased with COPD severity, where the majority (30.2%) had mild PH and the minority had severe PH (7.2%). Furthermore, we found a significant regional difference in the prevalence of COPD-related PH (P = 0.000), which was the highest in Africa (64.0%) and the lowest in Europe (30.4%). However, stratified studies on other factors involving mean age, sex, enrolment time, participant recruitment settings, and PH diagnostic methods showed no significant differences in prevalence (P >0.05).

Conclusion

The global incidence of PH in the COPD population is very high, and there are significant regional and international variations. Patients with COPD should be screened for PH and contributing risk factors to reduce the burden on individuals and society.

Pipersentan: A De Novo Synthetic Endothelin Receptor Antagonist that Inhibits Monocrotaline- and Hypoxia-Induced Pulmonary Hypertension

Background: Although major advances have been made in the pathogenesis and management of pulmonary arterial hypertension (PAH), the endothelin system is still considered to play a vital role in the pathology of PAH due to its vasoconstrictive action. Endothelin receptor antagonists (ERAs), either as monotherapy or in combination with other drugs, have attracted much attention in the treatment of this lethal disease, and research is continuing.

Methods: A novel ERA, pipersentan 5-(1,3-Benzodioxol-5-yl)-6-[2-(5-bromopyrimidin-2-yl)oxyethoxy]-N-(2-methoxyethylsulfamoyl)pyrimidin-4-amine, was recently synthesized and the physicochemical characterizations and the pharmacology both in vitro and in vivo were studied.

Results: This orally administered ERA can both competitively and selectively inhibit the binding of endothelin-1 (ET-1) to its receptors with good physicochemical characteristics. Pipersentan efficaciously antagonized the effects of ET-1 on pulmonary artery smooth muscle cell proliferation, migration and calcium mobilization and effectively improved right ventricular hypertrophy and pulmonary arterial pressure in both monocrotaline- and hypoxia-induced pulmonary hypertension (PH) rat models.

Conclusions: This profile identifies pipersentan as a new agent for treating ET-1 system activation-related PH.

Incidence and outcomes of pulmonary hypertension in the Ireland

INTRODUCTION

Pulmonary hypertension (PH) is a progressive disease of the pulmonary vasculature, which is characterised by premature morbidity and mortality. The aim of this study is to define the characteristics of PH in the national PH unit (NPHU) in Ireland between 2010 and 2020.

METHODS

Cases of PH which were referred to the NPHU between 2010 and 2020 were included. PH was defined as a mean pulmonary artery pressure ≥25 mm Hg at right heart catheterisation.

RESULTS

Four hundred and fifteen cases of PH were identified during the study period. Group 1 pulmonary arterial hypertension (PAH) accounted for 39% (n=163) of cases, with a calculated annual incidence of 3.11 per million population (95% CI 1.53 to 4.70). The leading PAH subgroup was connective tissue disease-associated PAH (CTD-PAH), which was responsible for 49% of PAH referrals. This was followed by idiopathic PAH, with an estimated annual incidence of 0.63 cases per million population. The mean age at PAH diagnosis was 56±15 years and 86% (n=111) received double-combination or triple-combination therapy within the first 12 months of diagnosis. The 1-year, 3-year and 5-year transplant-free survival for PAH was 89%, 75% and 65%. This was significantly lower for individuals with CTD-PAH relative to other PAH subgroups (p<0.05).

DISCUSSION

This study describes the incidence and outcomes of PH in Ireland. While the outcomes are comparable to other centres, the incidence of PAH and specific subgroups appears low, suggesting that improved disease awareness and case recognition are required. Furthermore, the survival of individuals with CTD-PAH is poor and requires additional exploration.

Connexins may play a critical role in cigarette smoke-induced pulmonary hypertension

Pulmonary hypertension (PH) is a chronic progressive disease characterized by pulmonary vasoconstriction and remodeling. It causes a gradual increase in pulmonary vascular resistance leading to right-sided heart failure, and may be fatal. Chronic exposure to cigarette smoke (CS) is an essential risk factor for PH group 3; however, smoking continues to be prevalent and smoking cessation is reported to be difficult. A majority of smokers exhibit PH, which leads to a concomitant increase in the risk of mortality. The current treatments for PH group 3 focus on vasodilation and long-term oxygen supplementation, and fail to stop or reverse PH-associated continuous vascular remodeling. Recent studies have suggested that pulmonary vascular endothelial dysfunction induced by CS exposure may be an initial event in the natural history of PH, which in turn may be associated with abnormal alterations in connexin (Cx) expression. The relationship between Cx and CS-induced PH development has not yet been directly investigated. Therefore, this review will describe the roles of CS and Cx in the development of PH and discuss the related downstream pathways. We also discuss the possible role of Cx in CS-induced PH. It is hoped that this review may provide new perspectives for early intervention.

Changes in the Characteristics and Initial Treatments of Pulmonary Hypertension Between 2008 and 2020 in Japan

Background

Pulmonary arterial hypertension (PAH) is a rare, progressive disease. The treatment landscape for PAH in Japan has evolved considerably in recent years, but there is limited knowledge of the changes in treatment practices or patient characteristics.

Objectives

The aim of this study was to evaluate the changes in characteristics and initial treatments for PAH in Japan over time.

Methods

This study used data from the Japan Pulmonary Hypertension Registry (JAPHR) to compare patient characteristics and treatment practices between 2008-2015 (n = 316) and 2016-2020 (n = 315).

Results

The mean ± standard deviation age at diagnosis increased from 47.9 ± 16.7 years in 2008-2015 to 52.7 ± 16.9 years in 2016-2020. The mean pulmonary arterial pressure decreased from 45.4 ± 15.0 to 38.6 ± 13.1 mm Hg. Idiopathic/hereditary PAH was the most common etiology in both periods (50.0% and 51.1%, respectively). The proportion of patients prescribed oral/inhaled combination therapies increased from 47.8% to 57.5%. Oral/inhaled combination therapies were frequently prescribed to patients with congenital heart disease-related PAH (81.8%). There was no significant trend in prescribing practices based on French low-risk criteria: among patients with 0, 1, 2, 3, or 4 criteria, 53.8%, 68.8%, 52.8%, 66.7%, and 39.4% were prescribed oral/inhaled combination therapies, and 0%, 16.7%, 27.0%, 17.3%, and 15.2% were prescribed oral/inhaled monotherapies. Macitentan, tadalafil, selexipag, and epoprostenol were the most frequently prescribed drugs.

Conclusions

The severity of PAH decreased over time in Japan. Oral/inhaled combination therapies were generally preferred. Physicians generally prescribed therapies after considering the patients’ hemodynamics and clinical severity. (Japan Pulmonary Hypertension Registry [JAPHR]; UMIN000026680)

Metabolomics-based mechanism exploration of pulmonary arterial hypertension pathogenesis: novel lessons from explanted human lungs

Pulmonary arterial hypertension has led to global health and social problems, but the pathogenic mechanism has not been fully elucidated. Dysregulated metabolism is closely associated with the pathogenesis of pulmonary arterial hypertension. Here, we investigated metabolic profile shifts to reveal the molecular mechanisms underlying pulmonary hypertension. Explanted lung tissues from 13 idiopathic pulmonary arterial hypertension patients, 5 pulmonary arterial hypertension associated with congenital heart disease patients, and 16 controls were collected for untargeted metabolomics analysis with liquid chromatography coupled with tandem mass spectrometry. The KEGG database and MetaboAnalyst 5.0 were used for pathway analysis. A Cox survival analysis model was applied to evaluate the predictive value of metabolites on prognosis. Protein expression levels in human and rat pulmonary arterial hypertension lungs and hypoxia-exposed human pulmonary artery smooth muscle cells were detected by Western blotting to study the molecular mechanisms. Significant differences in metabolites and metabolic pathways were identified among the pulmonary arterial hypertension subgroups and control tissues. The levels of spermine were positively correlated with the patients' cardiac output, and (2e)-2,5-dichloro-4-oxo-2-hexenedioic acid was positively correlated with the patients' serum creatinine levels. Patients with higher thymine levels had a better prognosis. Moreover, seven differential metabolites were associated with the AKT pathway. AKT pathway inactivation was confirmed in human and rat pulmonary hypertensive lungs and pulmonary artery smooth muscle cells exposed to hypoxia. Our findings provide the first metabolomics evidence for pulmonary arterial hypertension pathogenesis in human lungs and may contribute to the improvement in therapeutic strategies.

Implications of Hydrogen Sulfide in Development of Pulmonary Hypertension

The pathological mechanisms underlying pulmonary hypertension (PH), as well as its treatment strategy, are crucial issues in this field. This review aimed to summarize the pathological mechanisms by which the hydrogen sulfide (H2S) pathway contributes to PH development and its future implications. The data in this review were obtained from Medline and PubMed sources up to 2022 using the search terms "hydrogen sulfide" and "pulmonary hypertension". In the review, we discussed the significance of endogenous H2S pathway alteration in PH development and showed the advance of the role of H2S as the third gasotransmitter in the mechanisms for hypoxic PH, monocrotaline-induced PH, high blood flow-induced PH, and congenital heart disease-associated PH. Notably, H2S plays a crucial role in the development of PH via certain mechanisms, such as inhibiting the proliferation of pulmonary artery smooth muscle cells, suppressing the inflammation and oxidative stress of pulmonary artery endothelial cells, inducing pulmonary artery smooth muscle cell apoptosis, and interacting with other gaseous signaling pathways. Recently, a variety of H2S donors were developed, including naturally occurring donors and synthetic H2S donors. Therefore, understanding the role of H2S in PH development may help in further exploring novel potential therapeutic targets of PH.

Heart rate recovery in 1 minute after the 6-minute walk test predicts adverse outcomes in pulmonary arterial hypertension

Heart rate recovery in 1 minute (HRR1) after the end of the 6-minute walk test (6MWT) is a non-invasive method of determining autonomic dysfunction. This parameter remains largely unexplored in pulmonary arterial hypertension (PAH) registries. We aimed to define the cut-off value and accuracy for abnormal HRR1 after the 6MWT and to investigate the association between HRR1 and clinical worsening in patients with PAH. This composite outcome was defined as first occurrence of all-cause death OR hospitalization from any cause OR disease progression characterized by decreased ≥ 15% in six-minute walking distance from baseline AND start of new specific PAH treatment or persistent worsening of World Health Organization functional class (WHO-FC). We performed a prospective cohort study that included 102 consecutive patients with PAH confirmed by right heart catheterization that underwent an 6MWT upon the diagnosis, recruited from September 2004 to April 2020 and followed up until April 2021 or death. The median HRR1 was 18 beats (IQR: 10–22), 50 and 52 PAH patients with <18 beats and ≥18 beats, respectively. The best cut-off for HRR1 to discriminate clinical worsening was 17 beats, with area under the curve (AUC) of 0.704 (95%CI: 0.584–0.824). The internal validation model by bootstrap showed an AUC of 0.676 (95%CI: 0.566–0.786) and the most accurate value was obtained in the seventh year of follow-up (AUC = 0.711; 95%CI: 0.596–0.844). Patients with an HRR1 <18 beats at baseline had a median event-free time of 2.17 years (95%CI: 1.82 to 2.52) versus 4.75 years (95%CI: 1.43 to 8.07) from those with ≥18 beats. In conclusion, a HRR1 value of less than 18 beats may be a reliable indicator of poor prognosis in patients with PAH.

Subgroup Analysis in Pulmonary Hypertension-Specific Therapy Clinical Trials: A Systematic Review

Pulmonary hypertension (PH) treatment decisions are driven by the results of randomized controlled trials (RCTs). Subgroup analyses are often performed to assess whether the intervention effect will change due to the patient’s characteristics, thus allowing for individualized decisions. This review aimed to evaluate the appropriateness and interpretation of subgroup analyses performed in PH-specific therapy RCTs published between 2000 and 2020. Claims of subgroup effects were evaluated with prespecified criteria. Overall, 30 RCTs were included. Subgroup analyses presented: a high number of subgroup analyses reported, lack of prespecification, and lack of interaction tests. The trial protocol was not available for most RCTs; significant differences were found in those articles that published the protocol. Authors reported 13 claims of subgroup effect, with 12 claims meeting four or fewer of Sun’s criteria. Even when most RCTs were generally at low risk of bias and were published in high-impact journals, the credibility and general quality of subgroup analyses and subgroup claims were low due to methodological flaws. Clinicians should be skeptical of claims of subgroup effects and interpret subgroup analyses with caution, as due to their poor quality, these analyses may not serve as guidance for personalized care.

Lung-kidney interactions and their role in chronic kidney disease-associated pulmonary diseases

Chronic illnesses rarely present in a vacuum, devoid of other complications, and chronic kidney disease is hardly an exception. Comorbidities associated with chronic kidney disease lead to faster disease progression, expedited dialysis dependency, and a higher mortality rate. Although chronic kidney disease is most commonly accompanied by cardiovascular diseases and diabetes, there is clear cross talk between the lungs and kidneys pH balance, phosphate metabolism, and immune system regulation. Our present understanding of the exact underlying mechanisms that contribute to chronic kidney disease-related pulmonary disease is poor. This review summarizes the current research on kidney-pulmonary interorgan cross talk in the context of chronic kidney disease, highlighting various acute and chronic pulmonary diseases that lead to further complications in patient care. Treatment options for patients presenting with chronic kidney disease and lung disease are explored by assessing activated molecular pathways and the body's compensatory response mechanisms following homeostatic imbalance. Understanding the link between the lungs and kidneys will potentially improve health outcomes for patients and guide healthcare professionals to better understand how and when to treat each of the pulmonary comorbidities that can present with chronic kidney disease.

Mechanisms of pulmonary vascular dysfunction in pulmonary hypertension and implications for novel therapies

Pulmonary hypertension (PH) is a serious disease characterized by various degrees of pulmonary vasoconstriction and progressive fibroproliferative remodeling and inflammation of the pulmonary arterioles that lead to increased pulmonary vascular resistance, right ventricular hypertrophy, and failure. Pulmonary vascular tone is regulated by a balance between vasoconstrictor and vasodilator mediators, and a shift in this balance to vasoconstriction is an important component of PH pathology, Therefore, the mainstay of current pharmacological therapies centers on pulmonary vasodilation methodologies that either enhance vasodilator mechanisms such as the NO-cGMP and prostacyclin-cAMP pathways and/or inhibit vasoconstrictor mechanisms such as the endothelin-1, cytosolic Ca2+, and Rho-kinase pathways. However, in addition to the increased vascular tone, many patients have a "fixed" component in their disease that involves altered biology of various cells in the pulmonary vascular wall, excessive pulmonary artery remodeling, and perivascular fibrosis and inflammation. Pulmonary arterial smooth muscle cell (PASMC) phenotypic switch from a contractile to a synthetic and proliferative phenotype is an important factor in pulmonary artery remodeling. Although current vasodilator therapies also have some antiproliferative effects on PASMCs, they are not universally successful in halting PH progression and increasing survival. Mild acidification and other novel approaches that aim to reverse the resident pulmonary vascular pathology and structural remodeling and restore a contractile PASMC phenotype could ameliorate vascular remodeling and enhance the responsiveness of PH to vasodilator therapies.

Chronic Sigma 1 receptor activation alleviates right ventricular dysfunction secondary to pulmonary arterial hypertension

Sigma 1 receptor (S1R) has shown a preferable protective effect on left ventricular function, but whether it protects right ventricular (RV) function is still elusive.This study aimed to determine the effects of S1R on RV dysfunction secondary to pulmonary arterial hypertension.Sixty wild-type male Sprague–Dawley rats were randomly divided into the control group, the fluvoxamine group, the pulmonary arterial hypertension group and the pulmonary arterial hypertension combined with fluvoxamine group. Monocrotaline (60 mg/kg) was administered to induce pulmonary arterial hypertension, and fluvoxamine was given for 21 consecutive days to activate S1R after one week of monocrotaline administration. Echocardiographic, serologic, and histologic parameters, qRT-PCR, and western blotting were conducted after 4 weeks of monocrotaline administration.The expression of S1R was decreased in the right ventricle in pulmonary arterial hypertension. TAPSE, and the FAC of the right ventricle were significantly decreased, and RV EDP and the plasma concentration of N-terminal pro-B-type natriuretic peptide was increased in the pulmonary arterial hypertension group, but fluvoxamine partly restored those abnormalities (all P < 0.05). Moreover, pulmonary arteriole remodeling, and fibrosis and hypertrophy in the RV were shown in the pulmonary arterial hypertension group; interestingly, fluvoxamine recovered RV structural remodeling (all P < 0.05) but neither alleviated pulmonary arteriole remodeling nor reduced pulmonary artery pressure. Furthermore, S1R activation protects RV function by upgrading the NRF 2/HO 1-mediated antioxidant stress pathway. In conclusion, chronic S1R activation ameliorates structural remodeling and RV dysfunction secondary to pulmonary arterial hypertension without altering pulmonary artery pressure.

Diagnostic value of computed tomography-based pulmonary artery to aorta ratio measurement in chronic obstructive pulmonary disease with pulmonary hypertension: A systematic review and meta-analysis

OBJECTIVE

We conducted a meta-analysis to systematic assess the diagnostic value of computed tomography (CT)-based pulmonary artery to aorta (PA:A) ratio measurement in COPD with pulmonary hypertension (COPD-PH).

METHODS

Published studies referring to diagnostic accuracy of PA:A ratio for COPD-PH were screened out from PubMed, Embase, Web of science, China National Knowledge databases (CNKI), Wan fang databases, and VIP databases. We used bivariate random-effects model to estimate pooled sensitivity (SEN), specificity (SPE), positive and negative likelihood ratios (PLR and NLR, respectively), and diagnostic odds ratios (DOR). Summary receiver operating characteristic (SROC) curves and area under the curve (AUC) were also calculated to summarize the aggregate diagnostic performance.

RESULTS

Nine eligible studies were included and the pooled SEN was 69% (95% CI: 59 ~ 78), SPE was 85% (95% CI: 77 ~ 90), PLR was 4.5 (95% CI: 2.8 ~ 7.5), and NLR was 0.36 (95% CI: 0.26 ~ 0.51), respectively. DOR reached 13.00 (95% CI: 6.00 ~ 28.00), and value of AUC was 0.84 (95% CI: 0.81 ~ 0.87). Subgroup analysis indicated that when the value of PA:A ratio was equal or greater than one (PA/A ≥ 1), the combined SEN, SPE, AUC, and DOR was 69%, 89%, 0.90, and 19.65, respectively.

CONCLUSIONS

PA:A ratio is helpful for appraisal of COPD-PH, and PA/A ≥ 1 possessed prominent diagnostic accuracy.

Expression and clinical significance of circular RNA hsa_circ_0003416 in pediatric pulmonary arterial hypertension associated with congenital heart disease

Background

Circular RNAs (circRNAs) have been found to be involved in the development of pulmonary arterial hypertension (PAH). However, their diagnostic value in pediatric PAH remains unclear. This study aimed to examine the characteristic expression of the circRNA hsa_circ_0003416 in the plasma of children with PAH caused by congenital heart disease (CHD); the potential of hsa_circ_0003416 as a diagnostic biomarker was also investigated.

Methods

The plasma expression levels of hsa_circ_0003416 were determined via quantitative reverse transcription–polymerase chain reaction in 50 CHD patients, 50 PAH patients, and 20 healthy subjects; the associations between hsa_circ_0003416 levels and clinical data were analyzed thereafter. Receiver operating characteristic curves were employed to determine the diagnostic capacity of this circRNA.

Results

Expression levels of hsa_circ_0003416 in plasma were lower in the PAH‐CHD group than in the CHD and healthy control groups (p = 0.009 vs. healthy control group, p = 0.026 vs. CHD group). Moreover, hsa_circ_0003416 was found to be negatively associated with B‐type natriuretic peptide (r = −0.342, p = 0.013). In addition, the area under the curve of hsa_circ_0003416 levels in plasma was 0.721 (95% confidence intervals = 0.585–0.857, p = 0.004), suggesting that it has a promising diagnostic value.

Conclusions

Overall, hsa_circ_0003416 was found to be significantly downregulated in children with PAH‐CHD and to be potent as a biomarker for PAH‐CHD diagnosis.

HIV, Combination Antiretroviral Therapy, and Vascular Diseases in Men and Women

Thanks to the advent of combination antiretroviral therapy (cART), people living with human immunodeficiency virus (HIV) (PLWH) experienced a marked increase in life expectancy but are now at higher risk for cardiovascular disease (CVD), the current leading cause of death in PLWH on cART. Although HIV preponderantly affects men over women, manifestations of HIV-related CVD differ by sex with women experiencing greater risks than men. Despite extensive investigation, the etiopathology of CVD, notably the respective contribution of viral infection and cART, remain ill-defined. However, both viral infection and cART have been reported to contribute to endothelial dysfunction, the precursor and major cause of atherosclerosis-associated CVD, through mechanisms involving endothelial cell activation, inflammation, and oxidative stress, all leading to reduced nitric oxide bioavailability. Therefore, preserving endothelial function in PLWH on cART should be a main target to reduce CVD morbidity and mortality, notably in females.

Experimental Schistosoma japonicum-induced pulmonary hypertension

BACKGROUND

Schistosomiasis, a major cause of pulmonary arterial hypertension (PAH) worldwide, is most clearly described complicating infection by one species, Schistosoma mansoni. Controlled exposure of mice can be used to induce Type 2 inflammation-dependent S. mansoni pulmonary hypertension (PH). We sought to determine if another common species, S. japonicum, can also cause experimental PH.

METHODS

Schistosome eggs were obtained from infected mice, and administered by intraperitoneal sensitization followed by intravenous challenge to experimental mice, which underwent right heart catheterization and tissue analysis.

RESULTS

S. japonicum sensitized and challenged mice developed PH, which was milder than that following S. mansoni sensitization and challenge. The degree of pulmonary vascular remodeling and Type 2 inflammation in the lungs was similarly proportionate. Cross-sensitization revealed that antigens from either species are sufficient to sensitize for intravenous challenge with either egg, and the degree of PH severity depended on primarily the species used for intravenous challenge. Compared to a relatively uniform distribution of S. mansoni eggs, S. japonicum eggs were observed in clusters in the lungs.

CONCLUSIONS

S. japonicum can induce experimental PH, which is milder than that resulting from comparable S. mansoni exposure. This difference may result from the distribution of eggs in the lungs, and is independent of which species is used for sensitization. This result is consistent with the clearer association between S. mansoni infection and the development of schistosomiasis-associated PAH in humans.

Polydatin Glycosides Improve Monocrotaline-Induced Pulmonary Hypertension Injury by Inhibiting Endothelial-To-Mesenchymal Transition

Objective: To study the effect of polydatin on the injury of pulmonary arterial hypertension (PAH) induced by monocrotaline (MCT).

Methods: SD rats were induced to develop PAH injury by a single subcutaneous injection of MCT (60 mg/kg). From the second day, rats in the administration group were orally given sildenafil (20 mg/kg) and polydatin (30 or 60 mg/kg) for 3 weeks. At the end of the experiment, right ventricular hypertrophy (RVH) index of SD rats was calculated, pathological damage was assessed by HE staining, transcription levels of target genes were detected by RT-PCR and Elisa, and expression levels of Endothelial-to-mesenchymal transition (EndMT) related proteins were detected by immunohistochemistry (IHC) and immunofluorescence (IF). Finally, molecular docking analysis was used to verify the interaction of polydatin on the main targets.

Results: Polydatin could significantly restore the body function, reduce MCT-induced PAH injury, reduce serum biochemical indices; polydatin could effectively inhibit EndMT process by decreasing the expression of N-cadherin, β-catenin and vimentin; polydatin could down-regulate TAGLN expression and increase PECAM1 expression to reduce pulmonary vascular remodeling. The interaction between polydatin and EndMT target was confirmed by molecular docking operation.

Conclusion: Pharmacological experiments combined with Combining molecular docking was first used to clarify that polydatin can reduce the pulmonary endothelial dysfunction and pulmonary vascular remodeling induced by MCT by inhibiting EndMT. The results of the study provide new ideas for the further treatment of PAH injury.

Endothelial Senescence: A New Age in Pulmonary Hypertension

Pulmonary hypertension is an enigmatic, deleterious disease driven by multiple heterogeneous causes with a burgeoning proportion of older patients with complex, chronic comorbidities without adequate treatment options. The underlying endothelial pathophenotypes that direct vasoconstriction and panvascular remodeling remain both controversial and incompletely defined. This review discusses emerging concepts centered on endothelial senescence in pulmonary vascular disease. This principle proposes a more heterogeneous, dynamic pulmonary endothelium in disease; it provides a potentially unifying feature of endothelial dysfunction in pulmonary hypertension irrespective of cause; and it supports a clinically relevant link between aging and pulmonary hypertension like other chronic illnesses. Thus, taking cues from studies on aging and age-related diseases, we present possible opportunities and barriers to diagnostic and therapeutic targeting of senescence in pulmonary hypertension.

Hispanic Ethnicity and Social Determinants of Health in Pulmonary Arterial Hypertension: The Pulmonary Hypertension Association Registry

Rationale There is a noticeable underrepresentation of minorities in clinical trials and registries in pulmonary arterial hypertension (PAH). Prior studies evaluating the association between Hispanic ethnicity and clinical outcomes in patients with PAH have not assessed the socioeconomic profile of Hispanic individuals or the significance of social determinants of health in clinical outcomes. Objective To determine the association between Hispanic ethnicity, social determinants of health, and clinical outcomes in PAH. Methods Prospective cohort study of adult participants with PAH enrolled in the Pulmonary Hypertension Association Registry, a multicenter US-based registry of patients treated at Pulmonary Hypertension Care Centers. Participants were classified as Hispanics and non-Hispanic Whites, based on self-reported ethnicity. A comparison of baseline clinical and sociodemographic characteristics between groups was performed as well using absolute standardized differences (ASD). The primary outcome of the study was to assess transplant-free survival between Hispanics and non-Hispanic Whites. A Cox proportional hazards model was used for the multivariable analysis after adjusting for age, sex, PAH etiology, annual income, education level and health insurance. Results A total of 683 individuals were included, 98 (14.3%) of Hispanic ethnicity. Hispanic patients had impaired access to health care (31.6% vs. 12.9% Medicaid/uninsured; ASD 0.35), lower education level (72.6% vs. 94.0% high school graduates or higher; ASD 0.60) and lower annual income (32.0% vs. 17.4% with income <20,000 US dollars; ASD 0.47), as compared with non-Hispanic Whites. Hispanic patients had a higher frequency of ER visits and a higher number of hospitalizations, despite having similar disease severity (incidence rate ratio 1.452, 95% CI 1.326 - 1.590 and 1.428, 95% CI 1.292 - 1.577, respectively). While the unadjusted analysis showed a lower transplant/death hazard ratio for Hispanics (HR 0.47, 95% CI 0.24-0.94; p=0.032), there was no association between Hispanic ethnicity and outcome in the multivariable model after adjusting for social determinants of health and other covariates (HR 0.76, 95% CI 0.35-1.62; p=0.474). Conclusions Hispanic ethnicity was not associated with differences in survival after adjusting for social determinants of health and other factors. Social determinants of health are important to consider when assessing the association between ethnicity and outcomes in PAH.

The Role of Glutamine and Glutaminase in Pulmonary Hypertension

Pulmonary hypertension (PH) refers to a clinical and pathophysiological syndrome in which pulmonary vascular resistance and pulmonary arterial pressure are increased due to structural or functional changes in pulmonary vasculature caused by a variety of etiologies and different pathogenic mechanisms. It is followed by the development of right heart failure and even death. In recent years, most studies have found that PH and cancer shared a complex common pathological metabolic disturbance, such as the shift from oxidative phosphorylation to glycolysis. During the shifting process, there is an upregulation of glutamine decomposition driven by glutaminase. However, the relationship between PH and glutamine hydrolysis, especially by glutaminase is yet unclear. This review aims to explore the special linking among glutamine hydrolysis, glutaminase and PH, so as to provide theoretical basis for clinical precision treatment in PH.

Long-term mortality after pulmonary artery denervation stratified by baseline functional class in patients with pulmonary arterial hypertension: Long-term mortality after PADN stratified by functional class

AIMS

This study aimed to assess the long-term effects of pulmonary artery denervation (PADN) on mortality in patients with pulmonary arterial hypertension (PAH).

METHODS AND RESULTS

Between March 2012 and March 2018, a total of 120 patients with PAH, who underwent PADN treatment and were prospectively followed up, were analysed. Patients were classified into World Health Organization (WHO) Functional Class I and II (FC 1-2; n=46) and Functional Class III and IV (FC 3-4; n=74) according to their FC prior to PADN. The primary endpoint was lung transplantation-free mortality until March 2021. The secondary endpoint was a change in the six-minute walk distance (6MWD). During the median of 4.8 years of follow-up, 23 (19.2%) patients died, predominantly from the FC 3-4 group (25.7%), compared to 8.7% in the FC 1-2 group (p=0.034). The mortality rate at one year (2.2% vs 12.2%, p=0.087) and three years (6.5% vs 17.6%, p=0.102) was numerically low in the FC 1-2 group versus the FC 3-4 group, respectively. The median net increase of 6MWD was +29 m in the FC 1-2 group, compared to +60.5 m in the FC 3-4 group (p=0.037).

CONCLUSIONS

PADN results in significant improvements in survival at long-term follow-up, especially in patients with PAH in FC 3-4. This study was the continuation of the PADN-1 study which was registered at URL: http://www.chictr.trc.com.cn. Unique identifier: chiCTR-ONC-12002085.

Shufeiya Recipe Improves Monocrotaline-Induced Pulmonary Hypertension in Rats by Regulating SIRT3/FOXO3a and Its Downstream Signaling Pathways

Pulmonary hypertension (PH) is a chronic and progressive disease caused by obstructions and functional changes of small pulmonary arteries. Current treatment options of PH are costly with patients needing long-term taking medicine. The traditional Chinese medicine (TCM) compound "Shufeiya Recipe" was used to intervene in monocrotaline- (MCT-) induced pulmonary hypertension in rats. The rats were randomly divided into the control group, model group, positive drug (Sildenafil) group, and Shufeiya Recipe low-, moderate-, and high-dose groups. The improvement effect of the Shufeiya Recipe on the mean pulmonary artery pressure (mPAP) was assessed in PH rats, and pathological staining was used to observe the pathological changes of lung tissue. The impact of the Shufeiya Recipe on oxidative stress damage in rats with pulmonary hypertension and the regulation of SIRT3/FOXO3a and its downstream signaling pathways were determined. The results showed that Shufeiya Recipe could significantly downregulate mPAP and improve lung histopathological changes; downregulate serum levels of reactive oxygen species (ROS); upregulate the concentrations of COX-1 and COX-2 and the activity of Mn-SOD; inhibit oxidative response damage; promote the protein expression of SIRT3, FOXO3a, p-PI3K, p-AKT, and p-eNOS; increase the level of expression of NO, sGC, cGMP, and PKG; and downregulate the level of protein expression of Ras, p-MEK1/2, p-ERK1/2 and c-fos. These results indicate that Shufeiya Recipe can improve MCT-induced pulmonary hypertension in rats by regulating SIRT3/FOXO3a and its downstream PI3K/AKT/eNOS and Ras/ERK signaling pathways.

Dysregulated Immunity in Pulmonary Hypertension: From Companion to Composer

Pulmonary hypertension (PH) represents a grave condition associated with high morbidity and mortality, emphasizing a desperate need for innovative and targeted therapeutic strategies. Cumulative evidence suggests that inflammation and dysregulated immunity interdependently affect maladaptive organ perfusion and congestion as hemodynamic hallmarks of the pathophysiology of PH. The role of altered cellular and humoral immunity in PH gains increasing attention, especially in pulmonary arterial hypertension (PAH), revealing novel mechanistic insights into the underlying immunopathology. Whether these immunophysiological aspects display a universal character and also hold true for other types of PH (e.g., PH associated with left heart disease, PH-LHD), or whether there are unique immunological signatures depending on the underlying cause of disease are points of consideration and discussion. Inflammatory mediators and cellular immune circuits connect the local inflammatory landscape in the lung and heart through inter-organ communication, involving, e.g., the complement system, sphingosine-1-phosphate (S1P), cytokines and subsets of, e.g., monocytes, macrophages, natural killer (NK) cells, dendritic cells (DCs), and T- and B-lymphocytes with distinct and organ-specific pro- and anti-inflammatory functions in homeostasis and disease. Perivascular macrophage expansion and monocyte recruitment have been proposed as key pathogenic drivers of vascular remodeling, the principal pathological mechanism in PAH, pinpointing toward future directions of anti-inflammatory therapeutic strategies. Moreover, different B- and T-effector cells as well as DCs may play an important role in the pathophysiology of PH as an imbalance of T-helper-17-cells (T_H17) activated by monocyte-derived DCs, a potentially protective role of regulatory T-cells (T_reg) and autoantibody-producing plasma cells occur in diverse PH animal models and human PH. This article highlights novel aspects of the innate and adaptive immunity and their interaction as disease mediators of PH and its specific subtypes, noticeable inflammatory mediators and summarizes therapeutic targets and strategies arising thereby.

Metabolic profile in endothelial cells of chronic thromboembolic pulmonary hypertension and pulmonary arterial hypertension

Chronic thromboembolic pulmonary hypertension (CTEPH) and pulmonary arterial hypertension (PAH) are two forms of pulmonary hypertension (PH) characterized by obstructive vasculopathy. Endothelial dysfunction along with metabolic changes towards increased glycolysis are important in PAH pathophysiology. Less is known about such abnormalities in endothelial cells (ECs) from CTEPH patients. This study provides a systematic metabolic comparison of ECs derived from CTEPH and PAH patients. Metabolic gene expression was studied using qPCR in cultured CTEPH-EC and PAH-EC. Western blot analyses were done for HK2, LDHA, PDHA1, PDK and G6PD. Basal viability of CTEPH-EC and PAH-EC with the incubation with metabolic inhibitors was measured using colorimetric viability assays. Human pulmonary artery endothelial cells (HPAEC) were used as healthy controls. Whereas PAH-EC showed significant higher mRNA levels of GLUT1, HK2, LDHA, PDHA1 and GLUD1 metabolic enzymes compared to HPAEC, CTEPH-EC did not. Oxidative phosphorylation associated proteins had an increased expression in PAH-EC compared to CTEPH-EC and HPAEC. PAH-EC, CTEPH-EC and HPAEC presented similar HOXD macrovascular gene expression. Metabolic inhibitors showed a dose-dependent reduction in viability in all three groups, predominantly in PAH-EC. A different metabolic profile is present in CTEPH-EC compared to PAH-EC and suggests differences in molecular mechanisms important in the disease pathology and treatment.

Pulmonalarterielle Hypertonie bei Frauen

Die pulmonalarterielle Hypertonie (PAH) ist eine seltene Erkrankung mit vielen Untergruppen. Frauen sind wesentlich häufiger betroffen bei der „klassischen“ idiopathischen Form, der hereditären und bei der Kollagenose-assoziierten PAH. Es wird vermutet, dass der höhere Östrogenspiegel bei Frauen die Pathophysiologie mit Einengung der kleinen Pulmonalarteriolen als Ursache der PAH zumindest bei den Mutationsträgerinnen begünstigt. PAH-Patientinnen haben ähnliche Symptome wie betroffene Männer, sprechen aber möglicherweise anders auf gezielte PAH-Therapien an. Sie haben im Mittel ein längeres Überleben im Vergleich zu männlichen Patienten. In dieser Arbeit werden wir

ZIP12 Contributes to Hypoxic Pulmonary Hypertension by Driving Phenotypic Switching of Pulmonary Artery Smooth Muscle Cells

ABSTRACT

ZIP12, a plasmalemmal zinc transporter, reportedly promotes pulmonary vascular remodeling (PVR) by enhancing proliferation of pulmonary artery smooth muscle cells (PASMCs). However, the mechanisms of ZIP12 facilitating PASMCs proliferation remain incompletely appreciated. It has been acknowledged that proliferation-predisposing phenotypic switching of PASMCs can lead to PVR. Given that hypoxia triggers phenotypic switching of PASMCs and ZIP12 mediates PVR, this study aims to explore whether ZIP12-mediated phenotypic switching of PASMCs contributes to hypoxia-induced PVR. Rats were exposed to hypoxia (10% O2) for 3 weeks to induce PVR, and primary rat PASMCs were cultured under hypoxic condition (3% O2) for 48 hours to induce proliferation. Immunofluorescence, quantitative reverse transcription-polymerase chain reaction, and Western blot analysis were performed to detect the expression of target mRNAs and proteins. EdU incorporation and 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium assay were conducted to measure the proliferation of PASMCs. Hypoxia upregulated ZIP12 expression (both mRNA and protein) in pulmonary arteries and PASMCs. Knockdown of ZIP12 inhibited phenotypic switching of PASMCs induced by hypoxia. We propose that HIF-1α/ZIP12/pERK pathway could represent a novel mechanism underlying hypoxia-induced phenotypic switching of PASMCs. Therapeutic targeting of ZIP12 could be exploited to treat PVR.

Osthole alleviates pulmonary vascular remodeling by modulating microRNA-22-3p mediated lipid metabolic reprogramming

BACKGROUND

Pulmonary vascular remodeling is the key pathological feature of pulmonary arterial hypertension (PAH) characterized by a pattern of lipid-related insulin resistance(IR), hormonal derangements and metabolic reprogramming. Our previous studies have demonstrated osthole as natural coumarin compound derived from traditional Chinese medicine is a promising agent for the treatment of pulmonary vascular remodeling in PAH.

PURPOSE

The present study sought to delineate lipid metabolic modulatory mechanism of osthole against pulmonary vascular remodeling by employing an interdisciplinary strategy.

METHODS

Rat model with PAH induced with MCT and PASMCs proliferation model induced with PDGF-BB were established in this study. Serum and lung tissues were used to lipid-related IR, hormone related indexes, pulmonary vascular remodeling analysis. Then, lipid metabolic gene, key enzymes, metabolites and cell proliferation indexes were examined to investigate metabolic regulatory mechanism in vivo and vitro model of PAH.

RESULTS

Osthole significantly showed improvement of lipid-related IR and hormone dysregulation in rats with PAH evidenced by elevating testosterone, androgen receptor and cyclic guanosine monophosphate (cGMP), inhibiting phosphodiesterase-5(PDE-5), modulating lipid-related IR indexes total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), triglyceride (TG)/HDL-C ratio. Additionally, osthole limited key metabolic gene and enzymes to inhibit accumulation of decadienyl-l-carnitine in lipid metabolism, thus to promote oxidative phosphorylation and ATP production through inhibition of miRNA-22-3p, fatty acid translocase (CD36), fatty acid synthase (FAS), phospholipase A2 (PLA2), carnitine palmitoyltransferase 1A (CPT1A), hexokinase 2 (HK2), activation of metabolic switch isocitrate dehydrogenase 3α (IDH3α), NADH dehydrogenase 1 (ND1). We found for the first time miRNA-22-3p modulated PASMCs proliferation and vascular remodeling by regulating lipid metabolism reprogramming. Those modifications uncovered therapeutic mechanism of osthole against pulmonary vascular remodeling.

CONCLUSION

Our findings revealed the function of miRNA-22-3p in PASMCs and demonstrated a novel mechanism that miRNA-22-3p as a regulator can be targeted by osthole to greatly restore dysregulated lipid metabolism thus to alleviate pulmonary vascular remodeling in PAH, which provides novel insight into the potential therapeutic target for PAH, further highlights the development potential of osthole derived new drug against PAH.

Flavopiridol Mitigates the Progression of Monocrotaline-Induced Pulmonary Hypertension in Rats by Targeting Cyclin-Dependent Kinase 9

PURPOSE

To investigate the role of cyclin-dependent kinase 9 (CDK9) and the therapeutic potential of a CDK9 inhibitor (flavopiridol) in monocrotaline (MCT)-induced pulmonary hypertension (PH).

METHODS

For the in vivo experiments, rats with PH were established by a single intraperitoneal injection of MCT (60 mg/kg). After 2 weeks of MCT injection, rats were then treated with flavopiridol (5 mg/kg, i.p., twice a week) or vehicle for 2 weeks. For the in vitro experiments, human pulmonary artery smooth muscle cells (HPASMCs) were treated with flavopiridol (0.025-1 μM) or vehicle under hypoxic conditions. Hemodynamic recording, right ventricle histology, lung histology, and pulmonary arterial tissue isolation were performed. The expression levels of CDK9, RNA polymerase II, c-Myc, Mcl-1, and survivin were determined by qRT-PCR and western blotting, and the proliferation and apoptosis of rat pulmonary arterial tissues and/or HPASMCs were also assayed.

RESULTS

Compared to the control group, CDK9 was upregulated in pulmonary arterial tissues from MCT-induced PH rats and hypoxic cultured HPASMCs. Upregulation of CDK9 was associated with enhanced phosphorylation of the C-terminal domain (CTD) of RNA polymerase II (RNA pol II) at serine-2 (Ser-2), promoting the expression of prosurvival and antiapoptotic proteins (c-Myc, Mcl-1, and survivin). Furthermore, treatment with flavopiridol (5 mg/kg) significantly alleviated pulmonary artery remodeling and partially reversed the progression of MCT-induced PH. Consistently, flavopiridol (0.5 μM) treatment decreased the proliferation and induced the apoptosis of cultured HPASMCs under hypoxic conditions. As a result of CDK9 inhibition and subsequent inhibition of RNA pol II CTD phosphorylation at Ser-2, flavopiridol decreased c-Myc, Mcl-1, and survivin expression in isolated pulmonary small arteries, leading to cell growth inhibition and apoptosis.

CONCLUSION

Flavopiridol mitigates the progression of MCT-induced PH in rats by targeting CDK9.

Heart Disease and Stroke Statistics-2022 Update: A Report From the American Heart Association

BACKGROUND

The American Heart Association, in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, diet, and weight) and health factors (cholesterol, blood pressure, and glucose control) that contribute to cardiovascular health. The Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, congenital heart disease, rhythm disorders, subclinical atherosclerosis, coronary heart disease, heart failure, valvular disease, venous disease, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).

METHODS

The American Heart Association, through its Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States to provide the most current information available in the annual Statistical Update. The 2022 Statistical Update is the product of a full year's worth of effort by dedicated volunteer clinicians and scientists, committed government professionals, and American Heart Association staff members. This year's edition includes data on the monitoring and benefits of cardiovascular health in the population and an enhanced focus on social determinants of health, adverse pregnancy outcomes, vascular contributions to brain health, and the global burden of cardiovascular disease and healthy life expectancy.

RESULTS

Each of the chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.

CONCLUSIONS

The Statistical Update represents a critical resource for the lay public, policymakers, media professionals, clinicians, health care administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

Fabrication and Characterization of Alveolus-Like Scaffolds with Control of the Pore Architecture and Gas Permeability

The micrometer scale sac-like alveoli are the most important and essential unit for gas exchange in the lung. Thus, design and fabrication of scaffolds for alveoli regeneration by tissue engineering approach should meet a few topography and functional requests such as large surface area, flexibility, and high gas permeability to their native counterpart. Testing the gas permeability of scaffolds through a fast and simple technique is also highly demanded to assist new scaffold development. This study fabricated alveolus-like scaffolds with regular pore shape, high pore connectivity, and high porosity produced by inverse opal technique alongside randomly distrusted porous scaffolds by salt leaching technique from two different materials (polyurethane and poly(L-lactic acid)). The scaffold surface was modified by immobilization of VEGF. A facile and new technique based on the bubble meter principle enabling to measure the gas permeability of porous scaffolds conveniently has been developed specifically. The cellular response of the scaffolds was assessed by culturing with bone marrow mesenchymal stem cells and coculturing with lung epithelial NL20 and endothelial HUVECs. Our results showed that the newly designed gas permeability device provided rapid, nondestructive, reproducible, and accurate assessment of gas permeability of different scaffolds. The porous polyurethane scaffolds made by inverse opal method had much better gas permeability than other scaffolds used in this study. The cellular work indicated that with VEGF surface modification, polyurethane inverse opal scaffolds induced alveolus-like tissues and have promising application in lung tissue engineering.

Chronic Thromboembolic Pulmonary Hypertension: An Update

Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare disease observed in a small proportion of patients after acute pulmonary embolism (PE). CTEPH has a high morbidity and mortality rate, related to the PH severity, and a poor prognosis, which mirrors the right ventricular dysfunction involvement. Pulmonary endarterectomy (PEA) reduces pulmonary vascular resistance, making it the treatment of choice and should be offered to operable CTEPH patients, as significant symptomatic and prognostic improvement has been observed. Moreover, these patients may also benefit from the advances made in surgical techniques and pulmonary hypertension-specific medication. However, not all patients are eligible for PEA surgery, as some have either distal pulmonary vascular obstruction and/or significant comorbidities. Therefore, surgical candidates should be carefully selected by an interprofessional team in expert centers. This review aims at making an overview of the risk factors and latest developments in diagnostic tools and treatment options for CTEPH.

Prevalence, incidence, and survival of pulmonary arterial hypertension: A systematic review for the global burden of disease 2020 study

Pulmonary arterial hypertension (PAH) is characterized by increased resistance in the pulmonary arterioles as a result of remodeled blood vessels. We sought all available epidemiologic data on population‐based prevalence, incidence, and 1‐year survival of PAH as part of the Global Burden of Disease Study. We performed a systematic review searching Global Index Medicus (GIM) for keywords related to PAH between 1980 and 2021 and identified population‐representative sources of prevalence, incidence, and mortality for clinically diagnosed PAH. Of 6772 articles identified we found 65 with population‐level data: 17 for prevalence, 17 for incidence, and 58 reporting case fatality. Reported prevalence ranged from 0.37 cases/100,000 persons in a referral center of French children to 15 cases/100,000 persons in an Australian study. Reported incidence ranged from 0.008 cases/100,000 person‐years in Finland, to 1.4 cases/100,000 person‐years in a retrospective chart review at a clinic in Utah, United States. Reported 1‐year survival ranged from 67% to 99%. All studies with sex‐specific estimates of prevalence or incidence reported higher levels in females than males. Studies varied in their size, study design, diagnostic criteria, and sampling procedures. Reported PAH prevalence, incidence, and mortality varied by location and study. Prevalence ranged from 0.4 to 1.4 per 100,000 persons. Harmonization of methods for PAH registries would improve efforts at disease surveillance. Results of this search contribute to ongoing efforts to quantify the global burden of PAH.

A Clinical Approach to Multimodality Imaging in Pulmonary Hypertension

Pulmonary hypertension (PH) is a clinical condition characterized by progressive elevations in mean pulmonary artery pressures and right ventricular dysfunction, associated with significant morbidity and mortality. For resting PH to develop, ~50-70% of the pulmonary vasculature must be affected, suggesting that even mild hemodynamic abnormalities are representative of advanced pulmonary vascular disease. The definitive diagnosis of PH is based upon hemodynamics measured by right heart catheterization; however this is an invasive and resource intense study. Early identification of pulmonary vascular disease offers the opportunity to improve outcomes by instituting therapies that slow, reverse, or potentially prevent this devastating disease. Multimodality imaging, including non-invasive modalities such as echocardiography, computed tomography, ventilation perfusion scans, and cardiac magnetic resonance imaging, has emerged as an integral tool for screening, classifying, prognosticating, and monitoring response to therapy in PH. Additionally, novel imaging modalities such as echocardiographic strain imaging, 3D echocardiography, dual energy CT, FDG-PET, and 4D flow MRI are actively being investigated to assess the severity of right ventricular dysfunction in PH. In this review, we will describe the utility and clinical application of multimodality imaging techniques across PH subtypes as it pertains to screening and monitoring of PH.

Health Disparities and Differences in Health-Care-Utilization in Patients With Pulmonary Arterial Hypertension

INTRODUCTION

Mental disorders are common in patients with pulmonary arterial hypertension (PAH) and contribute to impaired quality of life (QoL). The impact of mental disorders on access to health care, differences in clinical parameters and treatment in patients with PAH is unclear. In this study we sought to assess the impact of mental disorders and other health disparities on health-care-utilization in patients with PAH.

METHODS

In a cross-sectional observational study of patients with PAH, mental disorders were characterized using a structed clinical interview. In addition, patients completed a self-administered questionnaire to assess QoL, symptoms of anxiety and depression, lifestyle-factors and educational status. Number of outpatient visits and communication events per year were calculated as a surrogate for health-care-utilization and were compared by the presence of mental disorder. Linear regression analysis was conducted to assess the impact on health-care-utilization.

RESULTS

117 patients with PAH participated in this study (70% female, median age 59 (interquartile range, 49-70) years). Significant differences between patients with or without mental disorders were found in anxiety, depression and QoL. There were no significant differences in clinical parameters. Patients with mental disorders had higher rates of outpatient visits and communication events than patients without mental disorders. Linear regression revealed a gain of 2.2 communication events per year in the presence of any mental disorders.

CONCLUSION

Mental disorders in patients with PAH are common and significantly affect health-care-utilization. This higher demand in patients with mental disorder needs to be addressed by physicians, psychiatrists and specialized nurses offering therapeutic strategies.

Abnormal pulmonary hemodynamics during exercise is associated with exercise capacity in COPD

BACKGROUND

Pulmonary hypertension (PH) is a frequent complication in COPD and it is associated with decreased exercise capacity and poor prognosis. We hypothesized that even in COPD patients without significant PH at rest, abnormal pulmonary hemodynamics during exercise affect exercise capacity.

METHODS

Consecutive COPD patients with clinically indicated right heart catheterization and resting mean pulmonary arterial pressure (mPAP) < 25 mmHg and age- and sex-matched controls with the same limits of pulmonary hemodynamics but no chronic lung disease who underwent clinical work-up including invasive hemodynamic assessment during exercise, were retrospectively analyzed. Chi-square tests were used to evaluate differences between groups for categorical data and Fisher's exact test or Mann-Whitney-U-tests for continuous variables. Associations were analyzed with Spearman rank correlation tests.

RESULTS

We included n = 26 COPD patients (female/male: 16/10, 66 ± 11 yr, FEV₁: 56 ± 25%predicted) and n = 26 matched controls (FEV₁: 96 ± 22%predicted). At rest, COPD patients presented with slightly increased mPAP (21 (18-23) vs. 17 (14-20) mmHg, p = 0.022), and pulmonary vascular resistance (PVR) [2.5 (1.9-3.0) vs. 1.9 (1.5-2.4) WU, p = 0.020] as compared to controls. During exercise, COPD patients reached significantly higher mPAP [47 (40-52) vs. 38 (32-44) mmHg, p = 0.015] and PVR [3.1 (2.2-3.7) vs. 1.7 (1.1-2.9) WU, p = 0.028] values despite lower peak exercise level [50 (50-75) vs. 100 (75-125) Watt, p = 0.002]. The mPAP/cardiac output slope was increased in COPD vs. controls [6.9 (5.5-10.9) vs. 3.7 (2.4-7.4) mmHg/L/min, p = 0.007] and negatively correlated with both peak oxygen uptake (r = - 0.46, p = 0.007) and 6-min walk distance (r = - 0.46, p = 0.001).

CONCLUSION

Even in the absence of significant PH at rest, COPD patients reveal characteristic abnormalities in pulmonary hemodynamics during exercise, which may represent an important exercise-limiting factor.

Childhood Trauma in Patients With PAH-Prevalence, Impact on QoL, and Mental Health-A Preliminary Report

BACKGROUND/OBJECTIVE

Child maltreatment is associated with increased risk of psychological consequences, contributes to morbidity and has long lasting effects on mental health and quality of life. Child maltreatment has not been assessed in patients with pulmonary arterial hypertension (PAH). We examined the prevalence of child maltreatment and determined their impact on disease severity in patients with PAH.

METHODS

A cross-sectional observational multicenter study at two PH centers in Germany was conducted. Patients with a confirmed diagnosis of PAH were given a self-administered questionnaire. Child maltreatment using the Childhood Trauma Questionnaire (CTQ), quality of life (QoL), anxiety, depression, and lifestyle factors were assessed and enhanced by clinical parameters 6-min walk distance (6MWD), WHO functional class (WHO FC), and serum levels of N-terminal fragment of pro-brain natriuretic peptide (NT-proBNP). Prevalence rates of child maltreatment were compared to the general population and impact of child maltreatment on disease severity was calculated by logistic regression analysis.

RESULTS

Two-hundred and seventeen patients, 71% female and a median age of 56 years were enrolled in this study. Patients with PAH had higher rates of emotional abuse and lower rates of physical neglect compared to the German population while rates of emotional neglect, physical abuse, and sexual abuse did not differ between patients and German population. Patients with any form of child maltreatment were more likely to be active smokers, had a worse QoL and more anxiety or depression. Moderate associations between child maltreatment, mental health, QoL, lifestyle factors and clinical parameters could be observed. Logistic regression analysis showed a significant impact of CTQ-total score on disease severity with an OR of 1.022 (95%-CI: 1.001-1.042, p = 0.035).

CONCLUSION

We found a higher rate of child maltreatment in patients with PAH in comparison to the German population. Correlations suggest moderate associations between CTQ-scores and mental health as well as QoL. Child maltreatment had significant impact on disease severity. However, effects were moderate. We conclude that child maltreatment has effects on mental health and quality of life in patients with PAH and may have limited effect on disease severity.

Stem Cell and Exosome Therapy in Pulmonary Hypertension

Pulmonary hypertension (PH) is a disease that eventually causes right heart failure by remodeling pulmonary blood vessels. Based on the histopathological characteristics, PH is categorized into five subgroups. Rarely, a severe clinical entity is pulmonary arterial hypertension (PAH), subgroup 1. This disease process results in pulmonary vascular alterations through dysfunction of the pulmonary endothelium and disturbance of immune responses. Although medical treatments based on these pathophysiologic concepts have been applied for more than 30 years, PAH still cannot be cured. This review addresses the feasibility of and perspectives on stem cell therapy, including the role of exosomes in PAH.

Pulmonary hypertension is a rare and progressive illness with a devastating prognosis. Promising research efforts have advanced the understanding and recognition of the pathobiology of pulmonary hypertension. Despite remarkable achievements in terms of improving the survival rate, reducing disease progression, and enhancing quality of life, pulmonary arterial hypertension (PAH) is not completely curable. Therefore, an effective treatment strategy is still needed. Recently, many studies of the underlying molecular mechanisms and technological developments have led to new approaches and paradigms for PAH treatment. Management based on stem cells and related paracrine effects, epigenetic drugs and gene therapies has yielded prospective results for PAH treatment in preclinical research. Further trials are ongoing to optimize these important insights into clinical circumstances.

The Roles of Dipeptidyl Peptidase 4 (DPP4) and DPP4 Inhibitors in Different Lung Diseases: New Evidence

CD26/Dipeptidyl peptidase 4 (DPP4) is a type II transmembrane glycoprotein that is widely expressed in various organs and cells. It can also exist in body fluids in a soluble form. DPP4 participates in various physiological and pathological processes by regulating energy metabolism, inflammation, and immune function. DPP4 inhibitors have been approved by the Food and Drug Administration (FDA) for the treatment of type 2 diabetes mellitus. More evidence has shown the role of DPP4 in the pathogenesis of lung diseases, since it is highly expressed in the lung parenchyma and the surface of the epithelium, vascular endothelium, and fibroblasts of human bronchi. It is a potential biomarker and therapeutic target for various lung diseases. During the coronavirus disease-19 (COVID-19) global pandemic, DPP4 was found to be an important marker that may play a significant role in disease progression. Some clinical trials on DPP4 inhibitors in COVID-19 are ongoing. DPP4 also affects other infectious respiratory diseases such as Middle East respiratory syndrome and non-infectious lung diseases such as pulmonary fibrosis, lung cancer, chronic obstructive pulmonary disease (COPD), and asthma. This review aims to summarize the roles of DPP4 and its inhibitors in infectious lung diseases and non-infectious diseases to provide new insights for clinical physicians.