Pulmonary hypertension in chronic lung disease and hypoxia

Inhibition of DYRK1A attenuates vascular remodeling in pulmonary arterial hypertension via suppressing STAT3/Pim-1/NFAT pathway

Pulmonary arterial hypertension (PAH) is characterized by progressive vascular remodeling caused by the excessive proliferation and survival of pulmonary artery smooth muscle cells (PASMCs). Dual-specificity tyrosine regulated kinase 1A (DYRK1A) is a pleiotropic kinase involved in the regulation of multiple biological functions, including cell proliferation and survival. However, the role and underlying mechanisms of DYRK1A in PAH pathogenesis remain unclear. We found that DYRK1A was upregulated in PASMCs in response to hypoxia, both in vivo and in vitro. Inhibition of DYRK1A by harmine significantly attenuated hypoxia-induced pulmonary hypertension and pulmonary artery remodeling. Mechanistically, we found that DYRK1A promoted pulmonary arterial remodeling by enhancing the proliferation and survival of PASMCs through activating the STAT3/Pim-1/NFAT pathway, because STAT3 gain-of-function via adeno-associated virus serotype 2 (AAV2) carrying the constitutively active form of STAT3 (STAT3C) nearly abolished the protective effect of harmine on PAH. Collectively, our results reveal a significant role for DYRK1A in pulmonary arterial remodeling and suggest it as a drug target with translational potential for the treatment of PAH.

Hypoxia and aging: molecular mechanisms, diseases, and therapeutic targets

Aging is a complex biological process characterized by the gradual decline of cellular functions, increased susceptibility to diseases, and impaired stress responses. Hypoxia, defined as reduced oxygen availability, is a critical factor that influences aging through molecular pathways involving hypoxia-inducible factors (HIFs), oxidative stress, inflammation, and epigenetic modifications. This review explores the interconnected roles of hypoxia in aging, highlighting how hypoxic conditions exacerbate cellular damage, promote senescence, and contribute to age-related pathologies, including cardiovascular diseases, neurodegenerative disorders, cancer, metabolic dysfunctions, and pulmonary conditions. By examining the molecular mechanisms linking hypoxia to aging, we identify key pathways that serve as potential therapeutic targets. Emerging interventions such as HIF modulators, antioxidants, senolytics, and lifestyle modifications hold promise in mitigating the adverse effects of hypoxia on aging tissues. However, challenges such as the heterogeneity of aging, lack of reliable biomarkers, and safety concerns regarding hypoxia-targeted therapies remain. This review emphasizes the need for personalized approaches and advanced technologies to develop effective antiaging interventions. By integrating current knowledge, this review provides a comprehensive framework that underscores the importance of targeting hypoxia-induced pathways to enhance healthy aging and reduce the burden of age-related diseases.

The Year in Cardiothoracic Transplant Anesthesia: Selected Highlights From 2022 Part I: Lung Transplantation

These highlights focus on the research in lung transplantation (LTX) that was published in 2022 and includes the assessment and optimization of candidates for LTX, donor optimization, the use of organs from donation after circulatory death, and outcomes when using marginal or novel donors; recipient factors affecting LTX, including age, disease, the use of extracorporeal life support; and special situations, such as coronavirus disease2019, pediatric LTX, and retransplantation. The remainder of the article focuses on the perioperative management of LTX, including the perioperative risk factors for acute renal failure (acute kidney injury); the incidence and management of phrenic nerve injury, delirium, and pain; and the postoperative management of hyperammonemia, early postoperative infections, and the use of donor-derived cell-free DNA to detect rejection.

Household fuel use and the regression from prehypertension to normotension among Chinese middle-aged and older adults: a cohort study

To examine the association of household fuel use with prehypertension regression among middle-aged and older people based on the China Health and Retirement Longitudinal Study (CHARLS), we included a total of 3501 participants with prehypertension at baseline, and they were followed up from 2011-2012 to 2015-2016 with information on blood pressure and household solid fuel use (heating and cooking fuels). Cox proportional hazards regression models were used to explore the hazard ratio (HR) and 95% confidence interval (CI) between fuel use and prehypertension regression. Additionally, we investigated the impact of switching fuels (2011-2013) on the regression to normotension during the 4-year follow-up. Linear regression was used to examine the effect of household fuel use on changes in blood pressure. Compared to solid fuel users, those who used clean fuel for heating at baseline had a positive effect on the regression of prehypertension (HR: 1.28, 95% CI: 1.08-1.53). Participants who used clean fuels for both heating and cooking had increased odds for the regression of prehypertension (HR: 1.32, 95% CI: 1.09-1.60). Compared to consistent solid fuel users, those who consistently used clean fuel for heating had a higher likelihood of transitioning from prehypertension to normotension (HR: 1.36, 95% CI: 1.06-1.73) and exhibited 2.45 mmHg lower systolic blood pressure. In conclusion, household clean fuel use for heating was positively associated with the regression of prehypertension to normotension. Furthermore, switching from solid fuel to clean fuel for heating could reduce the risk of prehypertension in Chinese middle-aged and older adults.

Dissecting the lung transcriptome of pulmonary fibrosis-associated pulmonary hypertension

Integrative multiomics can help elucidate the pathophysiology of pulmonary fibrosis (PF)-associated pulmonary hypertension (PH) (PF-PH). Weighted gene coexpression network analysis (WGCNA) was performed on a transcriptomic dataset of explanted lung tissue from 116 patients with PF. Patients were stratified by pulmonary vascular resistance (PVR), and differential gene expression analysis was conducted. Gene modules were correlated with hemodynamics at the time of transplantation and tested for enrichment in the lung transcriptomics signature of an independent pulmonary arterial hypertension (PAH) cohort. We found 1,250 differentially expressed genes between high and low PVR groups. WGCNA identified that black and yellowgreen modules negatively correlated with PVR, whereas the tan and darkgrey modules are positively correlated with PVR in PF-PH. In addition, the tan module showed the strongest enrichment for an independent PAH gene signature, suggesting shared gene expression patterns between PAH and PF-PH. Pharmacotranscriptomic analysis using the Connectivity Map implicated the tan and darkgrey modules as potentially pathogenic in PF-PH, given their combined module signature demonstrated a high negative connectivity score for treprostinil, a medication used in the treatment of PF-PH, and a high positive connectivity score for bone morphogenetic protein (BMP) loss of function. Pathway enrichment analysis revealed that inflammatory pathways and oxidative phosphorylation were downregulated, whereas epithelial-mesenchymal transition was upregulated in modules associated with increased PVR. Our integrative systems biology approach to the lung transcriptome of PF with and without PH identified several PH-associated coexpression modules and gene targets with shared molecular features with PAH warranting further investigation to uncover potential new therapies for PF-PH.NEW & NOTEWORTHY An integrative systems biology approach that included transcriptomic analysis of explanted lung tissue from patients with pulmonary fibrosis (PF) with and without pulmonary hypertension (PH) undergoing lung transplantation, combined with hemodynamic correlation and pharmacotranscriptomics, identified modules of genes associated with pulmonary vascular disease severity. Comparison with an independent pulmonary arterial hypertension (PAH) dataset identified shared gene expression patterns between PAH and PF-PH.

Treatment algorithm for pulmonary arterial hypertension

Pulmonary arterial hypertension leads to significant impairment in haemodynamics, right heart function, exercise capacity, quality of life and survival. Current therapies have mechanisms of action involving signalling via one of four pathways: endothelin-1, nitric oxide, prostacyclin and bone morphogenetic protein/activin signalling. Efficacy has generally been greater with therapeutic combinations and with parenteral therapy compared with monotherapy or nonparenteral therapies, and maximal medical therapy is now four-drug therapy. Lung transplantation remains an option for selected patients with an inadequate response to therapies.

Pulmonary hypertension associated with lung diseases

Pulmonary hypertension (PH) associated with chronic lung disease (CLD) is both common and underrecognised. The presence of PH in the setting of lung disease has been consistently shown to be associated with worse outcomes. Recent epidemiological studies have advanced understanding of the heterogeneity of this patient population and shown that defining both the specific type of CLD as well as the severity of PH (i.e. deeper phenotyping) is necessary to inform natural history and prognosis. A systematic diagnostic approach to screening and confirmation of suspected PH in CLD is recommended. Numerous uncontrolled studies and one phase 3 randomised, controlled trial have suggested a benefit in treating PH in some patients with CLD, specifically those with fibrotic interstitial lung disease (ILD). However, other studies in diseases such as COPD-PH showed adverse outcomes with some therapies. Given the expanding list of approved pharmacological treatments for pulmonary arterial hypertension, developing a treatment algorithm for specific phenotypes of CLD-PH is required. This article will summarise existing data in COPD, ILD and other chronic lung diseases, and provide recommendations for classification of CLD-PH and approach to the diagnosis and management of these challenging patients.

Pulmonary vascular resistance predicts the mortality in patients with bronchiectasis-associated pulmonary hypertension

OBJECTIVE

Pulmonary hypertension is a severe complication of bronchiectasis, characterized by elevated pulmonary vascular resistance (PVR) and subsequent right heart failure. The association between PVR and mortality in bronchiectasis-associated pulmonary hypertension has not been investigated previously.

METHODS

In the present study, a retrospective analysis was conducted on 139 consecutive patients diagnosed with bronchiectasis-associated pulmonary hypertension based on right heart catheterization, enrolled between January 2010 and June 2023. Baseline clinical characteristics and hemodynamic assessment were analyzed. The survival time for each patient was calculated in months from the date of diagnosis until the date of death or, if the patient was still alive, until their last visit.

RESULTS

Patients with bronchiectasis-associated pulmonary hypertension exhibited estimated survival rates of 89.5, 70, and 52.9 at 1-year, 3-year, and 5-year intervals respectively, with a median survival time of 67 months. Multivariable Cox regression analysis revealed that increased age [(adjusted hazard ratio per year 1.042, 95% confidence interval (CI) 1.008-1.076, P  = 0.015] and elevated PVR (adjusted HR per 1 Wood Units 1.115, 95% CI 1.015-1.224, P  = 0.023) were associated with an increased risk of all-cause mortality. In contrast, higher BMI was associated with a decreased risk of all-cause death (adjusted hazard ratio per 1 kg/m 2 0.915, 95% CI 0.856-0.979, P  = 0.009). Receiver-operating characteristic analyses identified a cutoff value for PVR at 4 Wood Units as predictive for all-cause death within 3 years [area under the curve (AUC) = 0.624; specificity= 87.5%; sensitivity= 35.8%; P  < 0.05]. Patients with a PVR greater than 4 Wood Units had a significantly higher risk of all-cause death compared with those with 4 Wood Units or less (adjusted hazard ratio 2.392; 95% CI 1.316-4.349; P  = 0.019). Notably, there were no significant differences in age, sex, BMI, WHO functional class, 6-min walk distance, and NT-proBNP levels at baseline between patients categorized as having 4 Wood Units or less or greater than 4 Wood Units for PVR.

CONCLUSION

Based on these data, PVR could serve as a discriminative marker for distinguishing between nonsevere pulmonary hypertension (PVR ≤ 4 Wood Units) and severe pulmonary hypertension (PVR > 4 Wood Units). The utilization of a PVR cutoff value of 4.0 Wood Units provides enhanced prognostic capabilities for predicting mortality.

Noninvasive diagnostic modalities and prediction models for detecting pulmonary hypertension associated with interstitial lung disease: a narrative review

Pulmonary hypertension (PH) is highly prevalent in patients with interstitial lung disease (ILD) and is associated with increased morbidity and mortality. Widely available noninvasive screening tools are warranted to identify patients at risk for PH, especially severe PH, that could be managed at expert centres. This review summarises current evidence on noninvasive diagnostic modalities and prediction models for the timely detection of PH in patients with ILD. It critically evaluates these approaches and discusses future perspectives in the field. A comprehensive literature search was carried out in PubMed and Scopus, identifying 39 articles that fulfilled inclusion criteria. There is currently no single noninvasive test capable of accurately detecting and diagnosing PH in ILD patients. Estimated right ventricular pressure (RVSP) on Doppler echocardiography remains the single most predictive factor of PH, with other indirect echocardiographic markers increasing its diagnostic accuracy. However, RVSP can be difficult to estimate in patients due to suboptimal views from extensive lung disease. The majority of existing composite scores, including variables obtained from chest computed tomography, pulmonary function tests and cardiopulmonary exercise tests, were derived from retrospective studies, whilst lacking validation in external cohorts. Only two available scores, one based on a stepwise echocardiographic approach and the other on functional parameters, predicted the presence of PH with sufficient accuracy and used a validation cohort. Although several methodological limitations prohibit their generalisability, their use may help physicians to detect PH earlier. Further research on the potential of artificial intelligence may guide a more tailored approach, for timely PH diagnosis.

COPD associated pulmonary hypertension: A post hoc analysis of the PERFECT study

The PERFECT study, a randomized, controlled, double-blind study of inhaled treprostinil in patients with COPD and associated pulmonary hypertension (PH-COPD) was a negative trial that was terminated early. The reason(s) for the negative outcome remains uncertain. A post hoc analysis of data from the PERFECT study was undertaken to identify adverse responders and possibly potential responders. The goal was also to provide insight into phenotypes for possible inclusion and exclusion in future PH-COPD clinical trials. An adverse response on active treatment was seen in 36.4% (24/66) of the subjects compared to 27.6% (16/58) on placebo. There was no evidence to suggest that hyperinflation, bronchospasm, or occult heart failure played any role in the untoward outcomes of the study. The patients who died during the study all had baseline diffusing capacity for carbon monoxide ≤25% of predicted. Evidence of a potential response was seen in 10.6% (7/66) of the patients who received inhaled treprostinil. Patients who had evidence of a treatment response had a baseline mean pulmonary artery pressure of ≥40 mmHg and a forced expiratory volume in the first second of ≥40%. Change in N-terminal prohormone of brain natriuretic peptide did not predict clinical response. This post hoc analysis provides information that may potentially enable improved selection of patients for future therapeutic trials in PH-COPD. These analyses are post hoc, observational, and exploratory. The thresholds defining the spectrum of responders are preliminary and may require further refinement and validation in future studies.

Towards a Better Prognosis in Patients with Systemic Sclerosis-Related Pulmonary Arterial Hypertension: Recent Developments and Perspectives

Precapillary pulmonary hypertension (PH) is a significant complication of systemic sclerosis (SSc). It represents one of the leading causes of morbidity and mortality, correlating with a significantly dismal prognosis and quality of life. Despite advancements in the management of patients with pulmonary arterial hypertension associated with SSc (SSc-PAH), no significant improvement has been reported in survival of patients with precapillary SSc-PH associated with extensive lung parenchyma disease. International expert consensus and guidelines for the management of PH recommend annual screening of SSc patients for early detection of pre-capillary PH. The implementation of screening algorithms capable of identifying patients with a high likelihood of developing PH could help limit unnecessary right-heart catheterization procedures and prevent significant delay in diagnosis. Furthermore, early initiation of up-front combination targeted therapy in patients with PAH has shown increase in survival rates, indicating that timely and aggressive medical therapy is key for stabilizing and even improving functional class, hemodynamic parameters and 6 min walking distance (6MWD) in this population. Further research is warranted into the benefit of PAH-targeted therapies in patients with PH associated with lung disease. Lastly, we discuss the potential role of immunosuppression using biologic agents in the therapeutic management of precapillary PH in SSc patients.

Exosomes derived from hypoxic alveolar epithelial cells promote the phenotypic transformation of pulmonary artery smooth muscle cells via the Rap1 pathway

Background: Hypoxic pulmonary hypertension (HPH) is one of the important pathophysiological changes in chronic pulmonary heart disease. Hypoxia promotes the phenotypic transformation of pulmonary artery smooth muscle cells (PASMCs). Extracellular exosomes regulate vascular smooth muscle cell (VSMC) phenotypic switch. Aim: Given the importance of exosomes and alveolar epithelial cells (AECs) in HPH, the present study aimed to address the issue of whether AEC-derived exosomes promote HPH by triggering PASMC phenotypic switch. Methods: Cell Counting Kit-8 (CCK-8), TRITC-phalloidin staining, and Western blotting were used to examine the effects of AEC-derived exosomes on cell proliferation, intracellular actin backbone distribution, and expression of phenotypic marker proteins in PASMCs. Transcriptomics sequencing was used to analyze differentially expressed genes (DEGs) between groups. Results: Hypoxia-induced exosomes (H-exos) could promote the proliferation of PASMCs, cause the reduction of cellular actin microfilaments, promote the expression of synthetic marker proteins (ELN and OPN), reduce the expression of contractile phenotypic marker proteins (SM22-α and α-SMA), and induce the phenotypic transformation of PASMCs. Transcriptomics sequencing analysis showed that the Rap1 signaling pathway was involved in the phenotypic transformation of PASMCs induced by H-exos. Conclusion: The present study identified that hypoxia-induced AEC-derived exosomes promote the phenotypic transformation of PASMCs and its mechanism is related to the Rap1 signaling pathway.

Diagnosis and Management of Pulmonary Hypertension: New Insights

Over the last decades, significant progress has been achieved in the pulmonary hypertension (PH) field. Pathophysiology of PH has been studied, leading to the classification of PH patients into five groups, while the hemodynamic definition has been recently revised. A diagnostic algorithm has been established and awareness has been raised in order to minimize diagnosis delay. The pulmonary arterial hypertension (PAH) treatment strategy includes the established three pathways of endothelin, nitric oxide-phosphodiesterase inhibitor, and prostacyclin pathway, but new therapeutic options are now being tested. The aim of this review is to summarize the existing practice and to highlight the novelties in the field of PH.

Utility of serum uric acid levels in excluding pulmonary hypertension in severe chronic lung disease: insights from a tertiary care center

Hyperuricemia is a known predictor of World Health Organization (WHO) Group 1 pulmonary hypertension (PH) (pulmonary arterial hypertension), but its role in excluding PH secondary to chronic lung diseases (WHO Group 3) remains unclear. We retrospectively analyzed data from 323 patients with severe chronic pulmonary diseases who underwent evaluation for lung transplantation at a tertiary medical center between June 2017 and February 2023. We examined the association between hyperuricemia (serum uric acid > 6 mg/dL or > 0.357 mmol/L) and PH [mean pulmonary arterial pressure (MPAP) > 20 mmHg]. Compared to the normouricemia group (n = 211), hyperuricemic patients (n = 112) were more likely to be younger (P = 0.02), male (P < 0.001), and present with PH (P = 0.001) and severe PH (MPAP > 35 mmHg; P < 0.001). These patients also had a higher body mass index (P = 0.004), plasma N-terminal pro-B-type natriuretic peptide (P < 0.001), serum creatinine (P < 0.001), and C-reactive protein levels (P = 0.03). Significant associations with PH included higher body mass index (P = 0.005), uric acid levels (P < 0.001), total lung capacity (P = 0.02), and residual volume (P = 0.01); shorter 6-min walk test distance (P = 0.005); and lower forced expiratory volume in one second (P = 0.006) and diffusing capacity for carbon monoxide (P < 0.001). Multivariate analysis showed elevated uric acid levels remained significantly associated with PH (OR 1.29, 95% CI 1.05-1.58, P = 0.01). In conclusion, normal serum uric acid levels serve as a significant predictor for excluding pulmonary hypertension in patients with severe chronic lung diseases.

Tobacco and COPD: presenting the World Health Organization (WHO) Tobacco Knowledge Summary

The WHO recently published a Tobacco Knowledge Summary (TKS) synthesizing current evidence on tobacco and COPD, aiming to raise awareness among a broad audience of health care professionals. Furthermore, it can be used as an advocacy tool in the fight for tobacco control and prevention of tobacco-related disease. This article builds on the evidence presented in the TKS, with a greater level of detail intended for a lung-specialist audience. Pulmonologists have a vital role to play in advocating for the health of their patients and the wider population by sharing five key messages: (1) Smoking is the leading cause of COPD in high-income countries, contributing to approximately 70% of cases. Quitting tobacco is an essential step toward better lung health. (2) People with COPD face a significantly higher risk of developing lung cancer. Smoking cessation is a powerful measure to reduce cancer risk. (3) Cardiovascular disease, lung cancer and type-2 diabetes are common comorbidities in people with COPD. Quitting smoking not only improves COPD management, but also reduces the risk of developing these coexisting conditions. (4) Tobacco smoke also significantly impacts children's lung growth and development, increasing the risk of respiratory infections, asthma and up to ten other conditions, and COPD later in life. Governments should implement effective tobacco control measures to protect vulnerable populations. (5) The tobacco industry's aggressive strategies in the marketing of nicotine delivery systems and all tobacco products specifically target children, adolescents, and young adults. Protecting our youth from these harmful tactics is a top priority.

New diagnostic criteria and current issues for pulmonary hypertension

In 2022, the European Society of Cardiology (ESC) and the European Respiratory Society (ERS) proposed new diagnostic criteria for pulmonary hypertension (PH). These criteria include significant changes to the definitions of pulmonary hemodynamic indices. Specifically, the threshold for mean pulmonary artery pressure (mPAP) has been lowered from ≥25 mmHg to >20 mmHg, and the threshold for pulmonary vascular resistance (PVR) has been adjusted from ≥3 Wood units (WU) to >2 WU. Additionally, the diagnostic criterion for exercise-induced PH has been reintroduced. To differentiate between non-severe and severe PH associated with lung disease, a differential threshold of 5 WU for PVR has been proposed. However, the threshold for mean pulmonary artery wedge pressure (PAWP) remains unchanged. While these new criteria could provide a more refined approach to clinical practice, they may also raise clinical concerns and questions regarding the diagnosis and management of PH.

Phosphodiesterase 5 Inhibitor Treatment Is Associated With Improved Survival in Pulmonary Hypertension Associated With COPD in the Pulmonary Vascular Research Institute GoDeep Meta-Registry

BACKGROUND

Patients with COPD frequently demonstrate pulmonary hypertension (PH). Severe PH in patients with COPD, identified by pulmonary vascular resistance (PVR) of > 5 Wood units (WU), is closely linked to impaired transplant-free survival. The impact of PH-targeting pharmacotherapy in this context remains unclear.

RESEARCH QUESTION

Is PH-targeted therapy associated with improved transplant-free survival in patients with COPD and PH?

STUDY DESIGN AND METHODS

This study included Pulmonary Vascular Research Institute GoDeep meta-registry patients with COPD and PH and available right heart catheterization at diagnosis. We investigated PH-targeted therapy prevalence and its association with transplant-free survival using diverse statistical methods, including Cox regression and subgroup analyses based on PH severity, comorbidities, and pulmonary function test results. Immortal time bias was addressed through a landmark approach.

RESULTS

As of December 2023, the GoDeep meta-registry included 26,981 patients (28% in PH group 1, 13% in PH group 2, 12% in PH group 3, 10% in PH group 4, 2% in PH group 5, 26% undefined, and 9% control participants). Of these, 836 patients had a diagnosis of COPD with PH and were included in this analysis, with median age of 66 years (59-73 years), FEV1 of 51% predicted (34%-69% predicted), mPAP of 35 mm Hg (28-44 mm Hg), PVR of 5 WU (4-8 WU), cardiac index of 2.5 L/min/m2 (2.0-2.9 L/min/m2), and mostly World Health Organization functional class III were included. Five-year transplant-free survival was 42%, significantly worse than in group 1 PH. A multivariable Cox proportional hazards model identified PVR, but not FEV1, as a major predictor of outcome. Four hundred eighteen patients (50%) received phosphodiesterase 5 inhibitor (PDE5i) therapy, which was associated with significantly reduced mortality: hazard ratio of 0.65 (0.57-0.75) for the entire cohort of patients with COPD and PH and of 0.83 (0.74-0.94) when performing landmark analysis. This PDE5i effect was reproduced robustly when performing subgroup analyses for patients with moderate to severe PH, various comorbidities, and supplemental oxygen requirement and when assessing the impact of unobserved confounders.

INTERPRETATION

Patients with COPD and PH exhibit poor transplant-free survival, with PVR being a predictor of mortality. In this meta-registry, PDE5i therapy was associated with a significant reduction in mortality across all tested models.

Pulmonary vasodilators in patients with advanced chronic kidney disease and pre-capillary pulmonary hypertension-A case series

Pulmonary hypertension (PH) is a prevalent complication among patients with chronic kidney disease (CKD). In these patients, pulmonary vasodilators may be useful but are underused. We describe a group of patients with precapillary PH and advanced CKD treated with pulmonary vasodilators. This was a case series of patients with CKD stage 4 and 5 and precapillary PH (isolated or combined) based on right heart catheterization (RHC) treated with pulmonary vasodilators from 2018 to 2023. Of 263 patients with isolated precapillary or combined PH and advanced CKD, only 17 (6%) were treated with pulmonary vasodilators; 53% (n = 9) with precapillary PH and 47% (n = 8) with combined PH. Most patients (94%, n = 16) received phosphodiesterase-5 antagonists, while 12% (n = 2) received endothelin receptor antagonists. Adverse clinical outcomes were seen in 35% of patients within a year. The use of pulmonary vasodilator did not prevent adverse outcomes in patients with precapillary PH and advanced CKD.

Pulmonary vascular disease in chronic lung diseases: cause or comorbidity?

PURPOSE OF REVIEW

To provide timely and relevant insights into the complex relationship between pulmonary vascular disease (PVD) and chronic lung disease (CLD), focusing on the causative and consequential dynamics between these conditions.

RECENT FINDINGS

There are shared pathogenic mechanisms between pulmonary arterial hypertension (PAH) and group 3 pulmonary hypertension, including altered expression of mediators and growth factors implicated in both conditions. Factors such as hypoxia, hypoxemia, and hypercapnia also contribute to pulmonary vascular remodelling and endothelial dysfunction. However, the role of hypoxia as the sole driver of pulmonary hypertension in CLD is being reconsidered, particularly in chronic obstructive pulmonary disease (COPD), with evidence suggesting a potential role for cigarette smoke products in initiating pulmonary vascular impairment. On the other hand, interstitial lung disease (ILD) encompasses a group of heterogeneous lung disorders characterized by inflammation and fibrosis of the interstitium, leading to impaired gas exchange and progressive respiratory decline, which could also play a role as a cause of pulmonary hypertension.

SUMMARY

Understanding the intricate interplay between the pulmonary vascular compartment and the parenchymal and airway compartments in respiratory disease is crucial for developing effective diagnostic and therapeutic strategies for patients with PVD and CLD, with implications for both clinical practice and research.

Contemporary Treatment of Pulmonary Arterial Hypertension: A U.S. Perspective

Pulmonary arterial hypertension (PAH) is a complex fatal condition that requires aggressive treatment with close monitoring. Significant progress has been made over the last three decades in the treatment of PAH, but, despite this progress, survival has remained unacceptably low. In the quest to improve survival, therapeutic interventions play a central role. In the last few years, there have been remarkable attempts to identify novel treatments. Finally, we have had a breakthrough with the discovery of the fourth treatment pathway in PAH. Activin signaling inhibition distinguishes itself as a potential antiproliferative intervention as opposed to the traditional therapies, which mediate their effect primarily by vasodilatation. With this novel treatment pathway, we stand at an important milestone with an exciting future ahead and the natural question of when to use an activin signaling inhibitor for the treatment of PAH. In this state-of-the-art review, we focus on the placement of this novel agent in the PAH treatment paradigm, based on the available evidence, with special focus on the U.S. patient population. This review also provides an expert opinion of the current treatment algorithm in important subgroups of patients with comorbidities from the U.S. perspective.

Selexipag for patients with pulmonary hypertension associated with lung disease: A preliminary study

BACKGROUND

Pulmonary arterial hypertension (PAH)-specific therapies are generally ineffective in patients with pulmonary hypertension associated with lung disease (PH-LD). The aim of this preliminary study was to evaluate the potential efficacy of selexipag, titrated according to individual tolerance, in patients with PH-LD.

METHODS

Consecutive patients diagnosed with PH-LD between October 2016 and March 2019, who received selexipag treatment, were retrospectively evaluated. Specific parameters, including changes in hemodynamic parameters, 6-min walk distance (6MWD), and partial pressure of atrial oxygen/fraction of inspiratory oxygen (PaO2/FiO2) were evaluated. Patients whose 6MWD improved ≥20 m were defined as responders.

RESULTS

Eight patients with PH-LD were included, comprising four with chronic obstructive pulmonary disease (COPD), two with interstitial lung disease (ILD) related to rheumatoid arthritis, one with ILD related to systemic sclerosis, and one with pulmonary Langerhans cell histiocytosis. No statistically significant improvements in hemodynamic parameters and 6MWD were noted following selexipag treatment. However, four patients showed improvements in 6MWD ≥20 m at follow-up and were considered responders. They had a higher body mass index (BMI) and lower PaO2/FiO2 at baseline than non-responders (p = 0.02 and p = 0.04, respectively). No Grade 3 or 4 adverse events were observed.

CONCLUSIONS

Selexipag was effective in half of the PH-LD cases, emphasizing higher BMI and lower PaO2/FiO2 as possible indicators for favorable response. Since selexipag starting at a low dose with subsequent titration may reduce the risk of early adverse events, it can be considered a treatment option for PH-LD. Further large-scale studies are warranted to confirm these findings.

Phenotypes in pulmonary hypertension

The clinical classification of pulmonary hypertension (PH) has guided diagnosis and treatment of patients with PH for several decades. Discoveries relating to underlying mechanisms, pathobiology and responses to treatments for PH have informed the evolution in this clinical classification to describe the heterogeneity in PH phenotypes. In more recent years, advances in imaging, computational science and multi-omic approaches have yielded new insights into potential phenotypes and sub-phenotypes within the existing clinical classification. Identification of novel phenotypes in pulmonary arterial hypertension (PAH) with unique molecular profiles, for example, could lead to new precision therapies. Recent phenotyping studies have also identified groups of patients with PAH that more closely resemble patients with left heart disease (group 2 PH) and lung disease (group 3 PH), which has important prognostic and therapeutic implications. Within group 2 and group 3 PH, novel phenotypes have emerged that reflect a persistent and severe pulmonary vasculopathy that is associated with worse prognosis but still distinct from PAH. In group 4 PH (chronic thromboembolic pulmonary disease) and sarcoidosis (group 5 PH), the current approach to patient phenotyping integrates clinical, haemodynamic and imaging characteristics to guide treatment but applications of multi-omic approaches to sub-phenotyping in these areas are sparse. The next iterations of the PH clinical classification are likely to reflect several emerging PH phenotypes and improve the next generation of prognostication tools and clinical trial design, and improve treatment selection in clinical practice.

Comparison of Contemporary Risk Scores in All Groups of Pulmonary Hypertension: A Pulmonary Vascular Research Institute GoDeep Meta-Registry Analysis

BACKGROUND

Pulmonary hypertension (PH) is a heterogeneous disease with a poor prognosis. Accurate risk stratification is essential for guiding treatment decisions in pulmonary arterial hypertension (PAH). Although various risk models have been developed for PAH, their comparative prognostic potential requires further exploration. Additionally, the applicability of risk scores in PH groups beyond group 1 remains to be investigated.

RESEARCH QUESTION

Are risk scores originally developed for PAH predictive in PH groups 1 through 4?

STUDY DESIGN AND METHODS

We conducted a comprehensive analysis of outcomes among patients with incident PH enrolled in the multicenter worldwide Pulmonary Vascular Research Institute GoDeep meta-registry. Analyses were performed across PH groups 1 through 4 and further subgroups to evaluate the predictive value of PAH risk scores, including the Registry to Evaluate Early and Long-Term PAH Disease Mangement (REVEAL) Lite 2, REVEAL 2.0, European Society of Cardiology/European Respiratory Society 2022, Comparative, Prospective Registry of Newly Initiated Therapies for Pulmonary Hypertension (COMPERA) 3-strata, and COMPERA 4-strata.

RESULTS

Eight thousand five hundred sixty-five patients were included in the study, of whom 3,537 patients were assigned to group 1 PH, whereas 1,807 patients, 1,635 patients, and 1,586 patients were assigned to group 2 PH, group 3 PH, and group 4 PH, respectively. Pulmonary hemodynamics were impaired with median mean pulmonary arterial pressure of 42 mm Hg (interquartile range, 33-52 mm Hg) and pulmonary vascular resistance of 7 Wood units (WU) (interquartile range, 4-11 WU). All risk scores were prognostic in the entire PH population and in each of the PH groups 1 through 4. The REVEAL scores, when used as continuous prediction models, demonstrated the highest statistical prognostic power and granularity; the COMPERA 4-strata risk score provided subdifferentiation of the intermediate-risk group. Similar results were obtained when separately analyzing various subgroups (PH subgroups 1.1, 1.4.1, and 1.4.4; PH subgroups 3.1 and 3.2; group 2 with isolated postcapillary PH vs combined precapillary and postcapillary PH; patients of all groups with concomitant cardiac comorbidities; and severe [> 5 WU] vs nonsevere PH).

INTERPRETATION

This comprehensive study with real-world data from 15 PH centers showed that PAH-designed risk scores possess predictive power in a large PH cohort, whether considered as common to the group or calculated separately for each PH group (1-4) and various subgroups.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT05329714; URL: www.

CLINICALTRIALS

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The impact of cardiovascular and lung comorbidities in patients with pulmonary arterial hypertension: A systematic review and meta-analysis

BACKGROUND

Contemporary patients with pulmonary arterial hypertension (PAH) are older and exhibit cardiovascular or/and lung comorbidities. Such patients have typically been excluded from major PAH drug trials. This systematic review compares baseline characteristics, hemodynamic parameters, and mortality rate between PAH patients with significant number of comorbidities compared to those with fewer or no comorbidities. ΜETHODS: A systematic literature search in PubMed, Web of Science, and Cochrane databases was conducted searching for studies comparing PAH patients with more than 2 cardiovascular comorbidities or/and at least a lung comorbidity against those with fewer comorbidities.

RESULTS

Seven observational studies were included. PAH patients with comorbidities were older, with an almost equal female-to-male ratio, shorter 6-minute walk distance, higher N-terminal pro-brain natriuretic peptide levels, and lower lung diffusion for carbon monoxide. In terms of hemodynamics, they had higher mean right atrial pressure and pulmonary artery wedge pressure, lower mean pulmonary arterial pressure, pulmonary vascular resistance and mixed venous oxygen saturation. Pooled analysis of 6 studies demonstrated a higher mortality risk for PAH patients with comorbidities compared to those without (HR 1.86, 95% CI 1.20 to 2.89, p < 0.001, I²=92%), with the subgroup of PAH patients with lung comorbidities having an even higher mortality risk (test for subgroup differences: p < 0.001). Combination drug therapy for PAH was less frequently used in patients with comorbidities.

CONCLUSIONS

Cardiovascular and lung comorbidities impact the clinical characteristics and outcomes of PAH patients, highlighting the need for optimal phenotyping and tailored management for this high-risk population.

The prognostic relevance of exercise pulmonary hypertension in cardiac and pulmonary diseases

PURPOSE OF REVIEW

In this review, we provide an overview of the prognostic implications of exPH in patients with various common cardiac and pulmonary diseases.

RECENT FINDINGS

Exercise pulmonary hypertension (exPH) has been recently re-introduced in the current European Society of Cardiology/European Respiratory Society pulmonary hypertension guidelines. Accordingly, exPH is defined as a mean pulmonary arterial pressure (mPAP)/cardiac output ( CO ) slope greater than 3 mmHg/l/min. Key considerations for this re-introduction included increasing understanding on normal pulmonary hemodynamics during exercise and the broadly available evidence on the association of an abnormal mPAP/ CO slope with poor survival in the general population and in different disease entities.

SUMMARY

Exercise (patho-)physiology has opened a new field for clinical research facilitating recognition of cardiovascular and pulmonary vascular diseases in an early stage. Such early recognition with significant prognostic and possibly therapeutic relevance, but being undetectable at rest, makes exercise pulmonary hemodynamics particularly interesting for common diseases, such as valvular heart disease, left heart disease, and chronic pulmonary disease.

A PrOsPective Cohort Study on Interstitial Lung Disease-Associated Pulmonary Hypertension with a ParticulaR Focus on the Subset with Pulmonary Arterial Hypertension Features (POPLAR Study)

INTRODUCTION

The pathogenesis and clinical profiles of patients with pulmonary hypertension (PH) associated with interstitial lung disease (ILD-PH) are poorly understood. Whether and to what extent pulmonary arterial hypertension (PAH)-specific therapy improves hemodynamic and outcome in ILD-PH are also unknown.

STUDY OBJECTIVE

This study aims to clarify the characteristics, clinical course and response to PAH-specific therapy of ILD and/or PH by enrolling three unique subsets: PAH, ILD-PH, and ILD.

METHODS

The proposed study is a retrospective and prospective, multi-centre, observational cohort study of patients treated at any of three university hospitals in the Hokkaido region of Japan who have any one of the following: PAH; ILD-PH with or without PAH features; or ILD without PH. We aim to enrol 250 patients in total. For the retrospective observation period, data obtained after 1 January 2010, will be analysed, and the prospective observation period will be 1 year. We will compare the clinical data of patients with ILD-PH with those of patients with PAH and those of patients with ILD without PH in the real-world clinical setting. In addition, within the cohort of patients with ILD-PH, we will explore the subset with "ILD-PH with PAH features" and compare the response to PAH-specific therapy with that of PAH. The primary outcome will be the change in pulmonary vascular resistance from first treatment to follow-up in patients with PAH and ILD-PH with PAH features (excluding ILD-PH without PAH feature and ILD-no-PH for the primary outcome). The exploratory outcomes will include analyses of PH-associated biomarkers, right ventricular function and patient-reported outcomes.

RESULTS

This is a protocol article and the results will be presented after data collection is completed.

CONCLUSION

The POPLAR study will provide data that help better understand the pathophysiology of ILD-PH and improve the quality of life and outcome of patients with PH and/or ILD.

TRIAL REGISTRATION

Japan Registry of Clinical Trials: jRCT1010230018.

The interplay between hyaluronic acid and stem cell secretome boosts pulmonary differentiation in 3D biomimetic microenvironments

Mesenchymal stem cells (MCSs) secretome provide MSC-like therapeutic effects in preclinical models of lung injury, circumventing safety concerns with the use of live cells. Secretome consists of Extracellular Vesicles (EVs), including populations of nano- to micro-sized particles (exosomes and microvesicles) delimited by a phospholipidic bilayer. However, its poor stability and bioavailability severely limit its application. The role of Hyaluronic acid (HA) as potential carrier in biomedical applications has been widely demonstrated. Here, we investigated the interplay between HA and MSCs- secretome blends and their ability to exert a bioactive effect on pulmonary differentiation in a 3D microenvironment mimicking lung niche. To this aim, the physical-chemical properties of HA/Secre blends have been characterized at low, medium and high HA Molecular Weights (MWs), by means of SEM/TEM, DLS, confocal microscopy and FTIR. Collectively physical-chemical properties highlight the interplay between the HA and the EVs. In 3D matrices, HA/Secre blends showed to promote differentiation in pulmonary lineage, improved as the MW of the HA in the blends decreased. Finally, HA/Secre blends' ability to cross an artificial mucus has been demonstrated. Overall, this work provides new insights for the development of future devices for the therapy of respiratory diseases that are still unmet.

Cardiovascular Risk in Patients with Chronic Obstructive Pulmonary Disease: A Systematic Review

Background/Objectives: A comprehensive and up-to-date review on cardiovascular disease (CVD) risk in patients with COPD is needed. Therefore, we aimed to systematically review the risk of a range of CVD in patients with COPD. Methods: We searched three databases (Pubmed, Web of Science, SCOPUS) from inception to September 2023 using terms related to COPD and CVD. Observational studies were included if they (1) were conducted in adults with a diagnosis of COPD based on the GOLD criteria, spirometry, physician diagnosis, or review of electronic health records; (2) reported the risk of CVD, namely of myocardial infarction (MI), ischaemic heart disease (IHD), atrial fibrillation (AF), heart failure, cerebrovascular disease, pulmonary hypertension, and peripheral vascular disease, compared with a control population using a measure of risk. A narrative synthesis was used. Results: Twenty-four studies from 2015 to 2023, mainly from Europe (n = 17), were included. A total of 3,485,392 patients with COPD (43.5-76.0% male; 63.9-73.5 yrs) and 31,480,333 (40.0-55.4% male, 49.3-70.0 yrs) controls were included. A higher risk of CVD in patients with COPD was evident regarding overall CVD, MI, IHD, heart failure, and angina. Higher risks of arrhythmia and AF, stroke, sudden cardiac death/arrest, pulmonary embolism, pulmonary hypertension, and peripheral vascular disease were also found, although based on a small amount of evidence. Conclusions: Patients with COPD have a higher risk of CVD than the general population or matched controls. This review underscores the need for vigilant and close monitoring of cardiovascular risk in individuals with COPD to inform more precise preventive strategies and targeted interventions to enhance their overall management.

A Case of Interstitial Lung Disease-Related Pulmonary Hypertension Successfully Treated with Inhaled Iloprost

Pulmonary hypertension (PH) associated with interstitial lung disease (ILD) (PH-ILD) significantly worsens clinical symptoms and survival, with no effective treatment available. This case report presents the successful treatment of PH-ILD with inhaled iloprost in a patient with idiopathic pulmonary fibrosis (IPF). The patient, a 68-year-old female, was diagnosed with IPF in 2018 and was maintained on pirfenidone. She experienced stable disease until March 2023, when she developed progressive exertional dyspnea, despite stability indicated by a computed tomography (CT) scan, without progression. Transthoracic echocardiography (TTE) and right heart catheterization (RHC) confirmed PH-ILD with a mean pulmonary artery pressure (mPAP) of 43 mmHg. Due to the ineffectiveness of sildenafil and a CT scan indicating stable IPF, a repeat RHC was performed, which showed a worsening of PH (mPAP 62 mmHg). Consequently, inhaled iloprost, at a dosage of 10 mcg every eight hours, was added to the existing antifibrotic agent. After two months, the patient experienced reduced exertional dyspnea and home oxygen requirements. By the seventh month, pulmonary function tests, the six-minute walk test, and RHC parameters (mPAP 37 mmHg) showed marked improvements. This case suggests that inhaled iloprost may be beneficial for managing PH-ILD. Further research is needed to confirm the efficacy of iloprost in PH-ILD treatment.

Non-invasive surrogate markers of pulmonary hypertension are associated with poor survival in patients with cancer

BACKGROUND

Cancer is one of the leading causes of death worldwide, and cardiopulmonary comorbidities may further adversely affect cancer prognosis. We recently described lung cancer-associated pulmonary hypertension (PH) as a new form of PH and comorbidity of lung cancer. While patients with lung cancer with PH had significantly reduced overall survival compared with patients without PH, the prevalence and impact of PH in other cancers remain unclear.

METHODS

In this retrospective, observational cohort study, we analysed the prevalence and impact of PH on clinical outcomes in 1184 patients with solid tumours other than lung cancer, that is, colorectal, head and neck, urological, breast or central nervous system tumours, using surrogate markers for PH determined by CT.

RESULTS

PH prevalence in this cohort was 10.98%. A Cox proportional hazard model revealed a significant reduction in the median survival time of patients with cancer with PH (837 vs 2074 days; p<0.001). However, there was no correlation between pulmonary metastases and PH. A subgroup analysis showed that PH was linked to decreased lung and cardiac function. Additionally, PH was associated with systemic arterial hypertension (p<0.001) and coronary artery disease (p=0.014), but not emphysema.

CONCLUSIONS

In this study, fewer patients with cancer had surrogate parameters for PH compared with previously published results among patients with lung cancer. Consequently, the prevalence of PH in other cancers might be lower compared with lung cancer; however, PH still has a negative impact on prognosis. Furthermore, our data does not provide evidence that lung metastases cause PH. Thus, our results support the idea that lung cancer-associated PH represents a new category of PH. Our results also highlight the importance of further studies in the field of cardio-oncology.

A Nitroreductase-Activatable Metabolic Reporter for Covalent Labeling of Pathological Hypoxic Cells in Tumorigenesis

Aberrant hypoxic stress will initiate a cascade of pathological consequence observed prominently in tumorigenesis. Understanding of hypoxia's role in tumorigenesis is highly essential for developing effective therapeutics, which necessitates reliable tools to specifically distinguish hypoxic tumor cells (or tissues) and correlate their dynamics with the status of disease in complex living settings for precise theranostics. So far, disparate hypoxia-responsive probe molecules and prodrugs were designed via chemical or enzymatic reactions, yet their capability in real-time reporting pathogenesis development is often compromised due to unrestricted diffusion and less selectivity towards the environmental responsiveness. Herein we present an oxygen-insensitive nitroreductase (NTR)-activatable glycan metabolic reporter (pNB-ManNAz) capable of covalently labeling hypoxic tumor cells and tissues. Under pathophysiological hypoxic environments, the caged non-metabolizable precursor pNB-ManNAz exhibited unique responsiveness to cellular NTR, culminating in structural self-immolation and the resultant ManNAz could incorporate onto cell surface glycoproteins, thereby facilitating fluorescence labeling via bioorthogonal chemistry. This NTR-responsive metabolic reporter demonstrated broad applicability for multicellular hypoxia labeling, particularly in the dynamic monitoring of orthotopic tumorigenesis and targeted tumor phototherapy in vivo. We anticipate that this approach holds promise for investigating hypoxia-related pathological progression, offering valuable insights for accurate diagnosis and treatment.

Considerations in the Diagnosis and Management of Pulmonary Hypertension Associated With Left Heart Disease

Pulmonary hypertension associated with left heart disease (PH-LHD) remains the most common cause of pulmonary hypertension globally. Etiologies include heart failure with reduced and preserved ejection fraction and left-sided valvular heart diseases. Despite the increasing prevalence of PH-LHD, there remains a paucity of knowledge about the hemodynamic definition, diagnosis, treatment modalities, and prognosis among clinicians. Moreover, clinical trials have produced mixed results on the usefulness of pulmonary vasodilator therapies for PH-LHD. In this expert review, we have outlined the critical role of meticulous hemodynamic evaluation and provocative testing for cases of diagnostic uncertainty. Therapeutic strategies-pharmacologic, device-based, and surgical therapies used for managing PH-LHD-are also outlined. PH-LHD in advanced heart failure, and the role of mechanical circulatory support in PH-LHD is briefly explored. An in-depth understanding of PH-LHD by all clinicians is needed for improved recognition and outcomes among patients with PH-LHD.

Targeting IL-11 to reduce fibrocyte circulation and lung accumulation in animal models of pulmonary hypertension-associated lung fibrosis

BACKGROUND AND PURPOSE

IL-11 is a member of the IL-6 family of cytokine initially considered as haematopoietic and cytoprotective factor. Recent evidence indicates that IL-11 promotes lung fibrosis and pulmonary hypertension in animal models and is elevated in lung tissue of patients with pulmonary fibrosis and pulmonary hypertension. Fibrocytes are bone marrow-derived circulating cells that participate in lung fibrosis and pulmonary hypertension, but the role of IL-11 on fibrocytes is unknown. We investigated the role of IL-11 system on fibrocyte activation in different in vitro and in vivo models of lung fibrosis associated with pulmonary hypertension.

EXPERIMENTAL APPROACH

Human fibrocytes were isolated from peripheral blood of six healthy donors. Recombinant human (rh)-IL-11 and soluble rh-IL-11 receptor, α subunit (IL-11Rα) were used to stimulated fibrocytes in vitro to measure:- cell migration in a chemotactic migration chamber, fibrocyte to endothelial cell adhesion in a microscope-flow chamber and fibrocyte to myofibroblast transition. Mouse lung fibrosis and pulmonary hypertension was induced using either IL-11 (s.c.) or bleomycin (intra-tracheal), while in the rat monocrotaline (intra-tracheal) was used. In vivo siRNA-IL-11 was administered to suppress IL-11 in vivo.

KEY RESULTS

RhIL-11 and soluble rhIL-11Rα promote fibrocyte migration, endothelial cell adhesion and myofibroblast transition. Subcutaneous (s.c.) IL-11 infusion elevates blood, bronchoalveolar and lung tissue fibrocytes. SiRNA-IL-11 transfection in bleomycin and monocrotaline animal models reduces blood and lung tissue fibrocytes and reduces serum CXCL12 and CXCL12/CXCR4 lung expression.

CONCLUSION AND IMPLICATIONS

Targeting IL-11 reduces fibrocyte circulation and lung accumulation in animal models of pulmonary hypertension-associated lung fibrosis.

An underrecognized phenotype of pulmonary emphysema with marked pulmonary gas exchange but with mild or moderate airway obstruction

In patients with pulmonary emphysema and mild to moderate airflow limitation, one does not expect the features marked exertional dyspnea and hypoxemia as well as a profound decrease in diffusing capacity of the lung for carbon monoxide (DLCO). Here we describe this phenotype and its prognosis. From our database, we retrospectively selected cases associating emphysema, exertional breathlessness, O2 requirement at least upon exercise, forced expiratory volume in 1 sec (FEV1) ≥ 50% predicted, and DLCO ≤ 50% predicted, without associated combined pulmonary fibrosis and emphysema, right-to-left shunt, or severe pulmonary hypertension. Over a 12-year period, we identified 16 patients with emphysema and the above presentation. At the initial evaluation, the median age was 62 years (interquartile range 53.8-68.9). The median FEV1 and DLCO% predicted and mean pulmonary artery pressure were 86 (65-95)%, 38 (31-41)%, and 20 (17-25) mm Hg, respectively. On room air, the median arterial partial pressure of oxygen and partial pressure of carbon dioxide in arterial blood were 63.5 (55.8-69) mm Hg and 34.5 (31-36) mm Hg with increased median alveolar-arterial oxygen difference (46 [39-51] mm Hg). After the initial evaluation, the respiratory condition worsened in 13 of 14 (92.8%) patients with one or more re-evaluations (median follow-up 2.6 [0.9-5.8] years). In 12, lung transplantation was considered. Four patients died after 5.8, 5.7, 7.1, and 0.8 years of follow-up, respectively. We describe an underrecognized phenotype of pulmonary emphysema featuring a particular profile characterized by marked exertional dyspnea, impaired pulmonary gas exchange with low DLCO and marked oxygen desaturation at least on exercise but with mild or moderate airway obstruction.

Sarcoidosis-associated pulmonary hypertension due to pulmonary arteries stenosis - a case report

BACKGROUND

Sarcoidosis-associated pulmonary hypertension (SAPH) is listed in Group 5 of the clinical classification of pulmonary hypertension, due to its complex and multifactorial pathophysiology. The most common cause of SAPH development is advanced lung fibrosis with the associated destruction of the vascular bed, and/or alveolar hypoxia. However, a substantial proportion of SAPH patients (up to 30%) do not have significant fibrosis on chest imaging. In such cases, the development of pulmonary hypertension may be due to the lesions directly affecting the pulmonary vasculature, such as granulomatous angiitis, pulmonary veno-occlusive disease, chronic thromboembolism or external compression of vessels by enlarged lymph nodes. Based on the case of a 69-year-old female who developed SAPH due to pulmonary arteries stenosis, diagnostic difficulties and therapeutic management are discussed.

CASE PRESENTATION

The patient, non-smoking female, diagnosed with stage II sarcoidosis twelve years earlier, presented with progressive dyspnoea on exertion, dry cough, minor haemoptysis and increasing oedema of the lower limbs. Computed tomography pulmonary angiography (CTPA) showed complete occlusion of the right upper lobe artery and narrowing of the left lower lobe artery, with post-stenotic dilatation of the arteries of the basal segments. The vascular pathology was caused by adjacent, enlarged lymph nodes with calcifications and fibrotic tissue surrounding the vessels. Pulmonary artery thrombi were not found. The patient was treated with systemic corticosteroid therapy and subsequently with balloon pulmonary angioplasty. Partial improvement in clinical status and hemodynamic parameters has been achieved.

CONCLUSIONS

An appropriate screening strategy is required for early detection of pulmonary hypertension in sarcoidosis patients. Once SAPH diagnosis is confirmed, it is crucial to determine the appropriate phenotype of pulmonary hypertension and provide the most effective treatment plan. Although determining SAPH phenotype is challenging, one should remember about the possibility of pulmonary arteries occlusion.

Altered hypoxia-induced cellular responses and inflammatory profile in lung fibroblasts from COPD patients compared to control subjects

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease characterized by chronic bronchitis, emphysema and vascular remodelling. The disease is associated with hypoxia, inflammation and oxidative stress. Lung fibroblasts are important cells in remodelling processes in COPD, as main producers of extracellular matrix proteins but also in synthesis of growth factors and inflammatory mediators.

METHODS

In this study we aimed to investigate if there are differences in how primary distal lung fibroblasts obtained from COPD patients and healthy subjects respond to hypoxia (1% O2) and pro-fibrotic stimuli with TGF-β1 (10 ng/mL). Genes and proteins associated with oxidative stress, endoplasmic reticulum stress, remodelling and inflammation were analysed with RT-qPCR and ELISA.

RESULTS

Hypoxia induced differences in expression of genes involved in oxidative stress (SOD3 and HIF-1α), ER stress (IRE1, PARK and ATF6), apoptosis (c-Jun and Bcl2) and remodelling (5HTR2B, Collagen7 and VEGFR2) in lung fibroblasts from COPD subjects compared to control subjects, where COPD fibroblasts were in general less responsive. The release of VEGF-C was increased after hypoxia, whereas TGF-β significantly reduced the VEGF response to hypoxia and the release of HGF. COPD fibroblasts had a higher release of IL-6, IL-8, MCP-1 and PGE2 compared to lung fibroblasts from control subjects. The release of inflammatory mediators was less affected by hypoxia, whereas TGFβ1 induced differences in inflammatory profile between fibroblasts from COPD and control subjects.

CONCLUSION

These results suggest that there is an alteration of gene regulation of various stress responses and remodelling associated mediator release that is related to COPD and hypoxia, where fibroblasts from COPD patients have a deficient response.

Investigation into the role of H2-Ab1 in vascular remodeling in pulmonary arterial hypertension via Bioinformatics

BACKGROUND

Pulmonary arterial hypertension (PAH) is a progressive disease of vascular remodeling characterized by persistent pulmonary arterial pressure elevation, which can lead to right heart failure and premature death. Given the complex pathogenesis and poor prognosis of PAH, the identification and investigation of biomarkers become increasingly critical for advancing further understanding of the disease.

METHODS

PAH-related datasets, GSE49114, GSE180169 and GSE154959, were downloaded from the publicly available GEO database. By performing WGCNA on the GSE49114 dataset, a total of 906 PAH-related key module genes were screened out. By carrying out differential analysis on the GSE180169 dataset, a total of 576 differentially expressed genes were identified. Additionally, the GSE154959 single-cell sequencing dataset was also subjected to differential analysis, leading to the identification of 34 DEGs within endothelial cells. By taking intersection of the above three groups of DEGs, five PAH-related hub genes were screened out, namely Plvap, Cyp4b1, Foxf1, H2-Ab1, and H2-Eb1, among which H2-Ab1 was selected for subsequent experiments.

RESULTS

A SuHx mouse model was prepared using the SU5416/hypoxia method, and the successful construction of the model was evaluated through Hematoxylin-Eosin staining, hemodynamic detection, fulton index, and Western Blot (WB). The results of WB and qRT-PCR demonstrated a significant upregulation of H2-Ab1 expression in SuHx mice. Consistent with the results of bioinformatics analysis, a time-dependent increase was observed in H2-Ab1 expression in hypoxia-treated mouse pulmonary artery endothelial cells (PAECs). To investigate whether H2-Ab1 affects the development and progression of PAH, we knocked down H2-Ab1 expression in PAECs, and found that its knockdown inhibited the viability, adhesion, migration, and angiogenesis, while concurrently promoted the apoptosis of PAECs.

CONCLUSION

H2-Ab1 could regulate the proliferation, apoptosis, adhesion, migration, and angiogenesis of PAECs.

Integrated approach of network pharmacology, molecular docking, and clinical observations in evaluating the efficacy and safety of Bufei Huoxue capsules for pulmonary hypertension associated with chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a persistent and progressive disorder characterized by airway or alveolar abnormalities, commonly leading to pulmonary hypertension (PH). This clinical observational study investigates the therapeutic mechanisms of Bufei Huoxue capsules (BHC) in treating PH in patients with COPD-linked PH (COPD-PH) using network pharmacology and molecular docking methods, and assesses the therapeutic efficacy and safety of BHCs. The active compounds and their target proteins in BHCs were sourced from the Traditional Chinese Medicine Systems Pharmacology database, with additional target proteins derived from the GeneCards and OMIM databases. An active network was constructed using Cytoscape 3.7.1, and interaction networks were established. Intersecting targets underwent Gene Ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis using the Metascape database. Network pharmacology and molecular docking studies demonstrated favorable binding affinities of BHC active ingredients, such as quercetin, bavachalcone, and isobavachin, for key targets including PTGS1, ESR1, and PTGS2. Gene Ontology enrichment analysis highlighted the involvement of these targets in processes such as the positive regulation of locomotion, the transmembrane receptor protein tyrosine kinase signaling pathway, and peptidyl-tyrosine phosphorylation. KEGG pathway analysis indicated their roles in pathways related to cancer, AGE-RAGE signaling in diabetic complications, and prostate cancer. BHCs exhibit therapeutic effects on COPD-PH through multi-component, multi-target, and multi-pathway interactions. This clinical observational study confirms the efficacy and safety of BHCs in improving cardiac and pulmonary functions, enhancing exercise tolerance, and elevating the quality of life in patients with COPD-PH.

Differences in Exercise Capacity, Ventilatory Efficiency, and Gas Exchange between Patients with Pulmonary Arterial Hypertension and Chronic Thromboembolic Pulmonary Hypertension Residing at High Altitude

Background

Cardiopulmonary exercise testing (CPET) assesses exercise capacity and causes of exercise limitation in patients with pulmonary hypertension (PH). At altitude, changes occur in the ventilatory pattern and a decrease in arterial oxygen pressure in healthy; these changes are increased in patients with cardiopulmonary disease. Our objective was to compare the response to exercise and gas exchange between patients with pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) residing at the altitude of Bogotá (2640 m).

Methods

All patients performed an incremental CPET with measurement of oxygen consumption ( VO 2 ), dead space (VD/VT), ventilatory equivalents (VE/ VCO 2 ), and alveolar-arterial oxygen gradient ( PA-aO 2 ). X 2 test and one-way analysis of variance were used for comparisons between PAH and CTEPH.

Results

We included 53 patients, 29 with PAH, 24 with CTEPH, and 102 controls as a reference of the normal response to exercise at altitude. CTEPH patients had a higher New York Health Association (NYHA) functional class than PAH (p = 0.037). There were no differences between patients with PAH and CTEPH in hemodynamics and VO 2 % of predicted (67.8 ± 18.7 vs. 66.0 ± 19.8, p < 0.05), but those with CTEPH had higher dyspnea, VD/VT (0.36 ± 0.09 vs. 0.23 ± 0.9, p < 0.001), VE/ VCO 2 (45.8 ± 7.1 vs. 39.3 ± 5.6, p < 0.001), and PA-aO 2 (19.9 ± 7.6 vs. 13.5 ± 7.6, p < 0.001) than PAH patients.

Conclusions

At altitude, patients with PH present severe alterations in gas exchange during exercise. There were no differences in exercise capacity between PAH and CTEPH, but patients with CTEPH had more dyspnea and greater alterations in gas exchange during exercise. CPET made it possible to identify alterations related to the pathophysiology of CTEPH that could explain the functional class and dyspnea in these patients.

Unmet need in pulmonary hypertension-associated interstitial lung disease (PH-ILD): a clinician survey of real-world management of PH-ILD in Europe

Background

With no approved therapies for pulmonary hypertension (PH) associated with interstitial lung disease (PH-ILD) in Europe, we surveyed clinician perceptions on PH-ILD management and unmet need to understand current real-world practices.

Methods

An online clinician survey on PH-ILD management was conducted in France, Germany, Italy, Spain and the UK.

Results

55 clinicians (78% pulmonologists), each managing a median 20 PH-ILD patients (interquartile range (IQR) 10-50), participated. Upon PH suspicion, clinicians referred a median 50% (IQR 20-73%) of patients for echocardiography alone and 35% (IQR 20-78%) for echocardiography, followed by right heart catheterisation. Upon diagnosis, a median 20% (IQR 9-30%), 40% (IQR 20-50%) and 35% (IQR 20-55%) of patients fell under the pulmonary arterial pressure ranges of 21-24 mmHg, 25-34 mmHg and >35 mmHg, respectively. 50% of patients received off-label treatment for their PH and, of those, off-label phosphodiesterase-5 inhibitor (PDE-5i), endothelin receptor antagonist (ERA) and prostacyclin analogues were prescribed first-line by 78%, 9% and 7% of clinicians, respectively. Upon PDE-5i non-response, 35% of clinicians proceed with an ERA, 35% with no further therapy. 55% of clinicians used dual-therapy. Yearly median inpatient admissions and emergency visits were 2.0 (IQR 1.3-2.9) and 1.5 (IQR 1.0-2.0), respectively (n=31 responses). Most clinicians (69%) highlighted lack of efficacy or evidence for current therapies as a key gap in PH-ILD management.

Conclusions

This study gives insight into real-world European PH-ILD diagnosis and management. With significant use of off-label treatment, there is a large unmet need due to lack of approved therapies. Despite updated guidelines, more evidence is needed to standardise PH-ILD management.

Scoping review of post-TB pulmonary vascular disease: Proceedings from the 2nd International Post-Tuberculosis Symposium

Tuberculosis (TB) may cause significant long-term cardiorespiratory complications, of which pulmonary vascular disease is most under-recognized. TB is rarely listed as a cause of pulmonary hypertension (PH) in most PH guidelines, yet PH may develop at various stages in the time course of TB, from active infection through to the post-TB period. Predisposing risk factors for the development of PH are likely multifactorial, involving active TB disease and post-TB lung disease (PTLD), host-related and environment-related factors. Moreover, post-TB PH should likely be classified in Group 3 PH, with the pathogenesis similarly complex and multifactorial as other Group 3 PH causes. Identifying risk factors that predispose to post-TB PH may aid in developing risk stratification criteria for early identification and referral for confirmatory diagnostic tests. Given that universal screening for PH in TB survivors may be impractical and unfeasible, a targeted screening approach for high-risk individuals would be sensible. In this scoping review of post-TB PH, resulting from the proceedings of the 2nd International Post-Tuberculosis Symposium, we aim to describe the epidemiology, risk factors, and pathophysiology of post-TB PH. We emphasize diagnosing PH with an alternative set of diagnostic guidelines in resource-constrained settings where right heart catheterization may not be feasible. Research to describe the burden and distribution of post-TB PH should be prioritized as there is a current gap in knowledge regarding the prevalence and incidence of post-TB PH among persons with TB.

Compartment-specific remodeling patterns in end-stage chronic obstructive pulmonary disease with and without severe pulmonary hypertension

BACKGROUND

In patients with end-stage chronic obstructive pulmonary disease (COPD), severe pulmonary hypertension (PH) is frequently associated with less severe airway obstruction as compared to mild or no PH. However, the histologic correlate of this finding is not clear. We aimed to quantify remodeling of pulmonary arteries, airways, and parenchyma in random samples of explanted end-stage COPD lungs.

METHODS

We quantified remodeling of small pulmonary arteries, small airways, and the degree of emphysema (mean interseptal distance [MID]) with dedicated software. As primary objective, we compared COPD patients with severe PH (SevPH-COPD) with age- and sex-matched MildPH-COPD. For comparison, we also investigated COPD lungs with no PH (NoPH-COPD), idiopathic PAH (IPAH), and healthy donors.

RESULTS

We included n = 17 SevPH-COPD (mPAP = 43 [39-45]mm Hg), n = 17 MildPH-COPD (mPAP = 28 [24-31]mm Hg), n = 5 NoPH-COPD (mPAP = 18 [16-19]mm Hg), n = 10 IPAH (mPAP = 72 [65-91]mm Hg), and n = 10 healthy donor lungs. SevPH-COPD versus MildPH-COPD was characterized by better preserved forced vital capacity (51% vs 40% predicted, p < 0.05), less emphysema (MID 169 µm vs 279 µm, p < 0.001), and less PAS-positive and CD45-positive mucosa cells (15% vs 22%, p = 0.063% and 5% vs 7%, p = 0.058) suggesting less airway inflammation. In COPD patients, intimal and medial thickening were strongly correlated with mPAP (r = 0.676, p < 0.001 and r = 0.595, p < 0.001). MID was negatively correlated with mPAP (r = -0.556, p < 0.001) and was highest in NoPH-COPD (mean 281 µm), suggesting that emphysema per se is not associated with PH.

CONCLUSIONS

End-stage COPD with severe PH is characterized by pronounced pulmonary vascular remodeling, less inflammation of small airways, and less emphysema as compared to COPD with mild PH or no PH, suggesting that COPD with severe PH may represent a unique phenotype of COPD.

Predictors of Mortality in Pulmonary Hypertension-Associated Chronic Lung Disease

Background/Objectives: Pulmonary hypertension (PH) often accompanies chronic lung diseases. Several chronic lung diseases with PH portends unfavorable outcomes. We investigated which variables in this cohort of patients with chronic lung disease and PH predicts mortality. Methods: This is a retrospective analysis of patients with chronic lung disease and PH at a single tertiary, academic center. The underlying lung disease included were COPD, IPF, other fibrotic ILD, non-fibrotic ILD, fibrotic sarcoidosis, and CPFE. All patients had right heart catheterization diagnostic of PH as well as pulmonary function testing data including 6 min walk testing. Univariable and multivariate Cox regression was performed to identify variables associated with mortality. Results: We identified 793 patients with chronic lung disease and PH. In total, 144 patients died prior to potential lung transplant. In multivariable Cox regression IPF, other fibrotic ILD, non-fibrotic ILD, and CPFE were significantly associated with an increased risk of mortality. Severe PH (PVR > 5 WU), FEV1 < 30% predicted, FVC < 40% predicted, 6 min walk distance < 150 m were also significantly associated with an increased risk of mortality. Conclusions: Carrying a diagnosis of IPF, CPFE, fibrotic ILD, or non-fibrotic ILD with PH has an increased risk of mortality as compared to COPD with PH. Hemodynamic, PVR > 5 WU, 6 min walk test less than 150 m, as well as spirometric data including FEV1 < 30% and FVC < 40% predicted were independently associated with an increased risk of death.

Bioinformatics analysis of hypoxia associated genes and inflammatory cytokine profiling in COPD-PH

Pulmonary hypertension (PH) in chronic obstructive pulmonary disease (COPD) is associated with worse clinical outcomes and decreased survival rates. In absence of disease specific diagnostic/therapeutic targets and unclear pathophysiology, there is an urgent need for the identification of potential genetic/molecular markers and disease associated pathways. The present study aims to use a bioinformatics approach to identify and validate hypoxia-associated gene signatures in COPD-PH patients. Additionally, hypoxia-related inflammatory profile is also explored in these patients. Microarray dataset obtained from the Gene Expression Omnibus repository was used to identify differentially expressed genes (DEGs) in a hypoxic PH mice model. The top three hub genes identified were further validated in COPD-PH patients, with chemokine (C-X-C motif) ligand 9 (CXCL9) and CXCL12 showing significant changes in comparison to healthy controls. Furthermore, multiplexed analysis of 10 inflammatory cytokines, tumor necrosis factor alpha (TNF-α), transforming growth factor β (TGF-β), interleukin 1-beta (IL-1β), IL-4, IL-5, IL-6, IL-13, IL-17, IL-18 and IL-21 was also performed. These markers showed significant changes in COPD-PH patients as compared to controls. They also exhibited the ability to differentially diagnose COPD-PH patients in comparison to COPD. Additionally, IL-6 and IL-17 showed significant positive correlation with systolic pulmonary artery pressure (sPAP). This study is the first report to assess the levels of CXCL9 and CXCL12 in COPD-PH patients and also explores their link with the inflammatory profile of these patients. Our findings could be extended to better understand the underlying disease mechanism and possibly used for tailoring therapies exclusive for the disease.

The clinical and hemodynamic characteristics of pulmonary hypertension in patients with OSA-COPD overlap syndrome

BACKGROUND

Our study aimed to assess the clinical and hemodynamic characteristics of pulmonary hypertension (PH) in patients with overlapping obstructive sleep apnea (OSA) and chronic obstructive pulmonary disease (COPD), referred to OSA-COPD overlap syndrome (OS).

METHODS

We enrolled a total of 116 patients with OS, COPD, or OSA who underwent right heart catheterization (RHC) due to suspected PH. We conducted a retrospective analysis of the clinical and hemodynamic characteristics of these patients.

RESULTS

Among the three groups (OS group, n = 26; COPD group, n = 36; OSA group, n = 54), the prevalence of PH was higher in the OS group (n = 17, 65.4%)compared to OSA group (n = 26,48.1%) and COPD group (n = 20,55.6 %). Among three groups with PH, the superior vena cava pressure (CVP) and right ventricular pressure (RAP) were higher in the OS group than in the OSA group (P < 0.05). Patients in the OS and COPD groups had higher pulmonary artery wedge pressure (PAWP) than in the OSA group (14.88 ± 4.79 mmHg, 13.45 ± 3.68 mmHg vs. 11.00 ± 3.51 mmHg, respectively, P < 0.05). OS patients with PH exhibited higher respiratory event index (REI), time spent with SpO2 <90%, oxygen desaturation index (ODI), minimal SpO2 (MinSpO2) and mean SpO2 (MSpO2) compared to OS patients without PH. After adjusting for potential covariates, we found that MinSpO2 (OR 0.937, 95 % CI 0.882-0.994, P = 0.032), MSpO2 (OR 0.805, 95% CI 0.682-0.949, P = 0.010), time spent with SpO2 <90% (OR 1.422, 95% CI 1.137-1.780, P = 0.002), and FEV1 % pred (OR 0.977, 95 % CI 0.962-0.993, P = 0.005) were related to the development of PH.

CONCLUSIONS

Patients with OS showed higher prevalence of PH, along with higher PAWP, CVP and RAP. Worse nocturnal hypoxemia was found in OS patients with PH.

PD-1+ T lymphocyte proportions and hospitalized exacerbation of COPD: a prospective cohort study

OBJECTIVE

To evaluate the predictive value of PD-1 expression in T lymphocytes for rehospitalization due to acute exacerbations of COPD (AECOPD) in discharged patients.

METHODS

115 participants hospitalized with COPD (average age 71.8 ± 6.0 years) were recruited at Fujian Provincial Hospital. PD1+T lymphocytes proportions (PD1+T%), baseline demographics and clinical data were recorded at hospital discharge. AECOPD re-admission were collected at 1-year follow-up. Kaplan-Meier analysis compared the time to AECOPD readmissions among groups stratified by PD1+T%. Multivariable Cox proportional hazards regression and stratified analysis determined the correlation between PD1+T%, potential confounders, and AECOPD re-admission. ROC and DCA evaluated PD1+T% in enhancing the clinical predictive values of Cox models, BODE and CODEX.

RESULTS

68 participants (59.1%) were AECOPD readmitted, those with AECOPD readmission exhibited significantly elevated baseline PD-1+CD4+T/CD4+T% and PD-1+CD8 + T/CD8 + T% compared to non-readmitted counterparts. PD1+ T lymphocyte levels statistically correlated with BODE and CODEX indices. Kaplan-Meier analysis demonstrated that those in Higher PD1+ T lymphocyte proportions had reduced time to AECOPD readmission (logRank p < 0.05). Cox analysis identified high PD1+CD4+T and PD1+CD8+T ratios as risk factors of AECOPD readmission, with hazard ratios of 1.384(95%CI [1.043-1.725]) and 1.401(95%CI [1.013-1.789]), respectively. Notably, in patients aged < 70 years and with fewer than twice AECOPD episodes in the previous year, high PD1+T lymphocyte counts significantly increased risk for AECOPD readmission(p < 0.05). The AECOPD readmission predictive model, incorporating PD1+T% exhibited superior discrimination to the Cox model, BODE index and CODEX index, AUC of ROC were 0.763(95%CI [0.633-0.893]) and 0.734(95%CI [0.570-0.899]) (DeLong's test p < 0.05).The DCA illustrates that integrating PD1+T% into models significantly enhances the utility in aiding clinical decision-making.

CONCLUSION

Evaluation of PD1+ lymphocyte proportions offer a novel perspective for identifying high-risk COPD patients, potentially providing insights for COPD management.

TRIAL REGISTRATION

Chinese Clinical Trial Registry (ChiCTR, URL: www.chictr.org.cn/ ), Registration number: ChiCTR2200055611 Date of Registration: 2022-01-14.

Phase 1 Study of MK-5475, an Inhaled Soluble Guanylate Cyclase Stimulator, in Participants with Pulmonary Hypertension Associated with Chronic Obstructive Pulmonary Disease

Purpose

This phase 1 study (NCT04370873) evaluated safety and pharmacokinetics/pharmacodynamics (PK/PD) of MK-5475 in participants with pulmonary hypertension associated with COPD (PH-COPD).

Methods

Eligible participants were 40-80 years old with COPD (FEV1/FVC <0.7; FEV1 >30% predicted) and PH (mean pulmonary arterial pressure ≥25 mmHg). Participants were randomized 2:1 to MK-5475 or placebo via dry-powder inhaler once daily for 7 days in Part 1 (360 µg) or 28 days in Part 2 (380 µg). Safety was assessed by adverse events (AEs) and arterial blood oxygenation. Part-2 participants had pulmonary vascular resistance (PVR; primary PD endpoint) and pulmonary blood volume (PBV; secondary PD endpoint) measured at baseline and Day 28. A non-informative prior was used to calculate posterior probability (PP) that the between-group difference (MK-5475 - placebo) in mean percent reduction from baseline in PVR was less than -15%.

Results

Nine participants were randomized in Part 1, and 14 participants in Part 2. Median age of participants (86.4% male) was 68.5 years (41-77 years); 95.5% had moderate-to-severe COPD. Incidences of AEs were comparable between MK-5475 and placebo: overall (5/14 [36%] versus 5/8 [63%]), drug-related (1/14 [7%] versus 2/8 [25%]), and serious (1/14 [7%] versus 1/8 [13%]). MK-5475 caused no meaningful changes in arterial blood oxygenation or PBV. MK-5475 versus placebo led to numerical improvements from baseline in PVR (-21.2% [95% CI: -35.4, -7.0] versus -5.4% [95% CI: -83.7, 72.9]), with between-group difference in PVR less than -15% and calculated PP of 51%.

Conclusion

The favorable safety profile and numerical reductions in PVR observed support further clinical development of inhaled MK-5475 for PH-COPD treatment.

Risk factors associated with pulmonary hypertension in patients with active tuberculosis and tuberculous destroyed lung: a retrospective study

Pulmonary tuberculosis (TB) can result in irreversible damage and lead to tuberculous destructive lung (TDL), a severe chronic lung disease that is associated with a high mortality rate. Additionally, pulmonary hypertension (PH) is a hemodynamic disorder that can be caused by lung diseases. The objective of this study is to investigate the risk factors associated with PH in active TB patients diagnosed with TDL. We conducted a retrospective review of the medical records of 237 patients who were diagnosed with TDL, active pulmonary tuberculosis, and underwent echocardiography at the Third People' Hospital of Shenzhen from January 1, 2016, to June 30, 2023. Univariate and multivariate logistic regression analyses were performed to identify factors that correlated with the development of pulmonary hypertension. Univariate and multivariate logistic regression analyses revealed that several factors were associated with an increased risk of pulmonary hypertension (PH) in individuals with tuberculosis destroyed lung (TDL). These factors included age (OR = 1.055), dyspnea (OR = 10.728), D-dimer (OR = 1.27), PaCO2 (OR = 1.040), number of destroyed lung lobes (OR = 5.584), bronchiectasis (OR = 3.205), and chronic pleuritis (OR = 2.841). When age, D-dimer, PaCO2, and number of destroyed lung lobes were combined, the predictive value for PH in patients with TDL was found to be 80.6% (95% CI 0.739-0.873),with a sensitivity of 76.6% and specificity of 73.2%. Advanced age, elevated D-dimer levels, hypercapnia, and severe lung damage were strongly correlated with the onset of PH in individuals with active pulmonary tuberculosis (PTB) and TDL. Furthermore, a model incorporating age, D-dimer, PaCO2, and the number of destroyed lung lobes might be valuable in predicting the occurrence of PH in patients with active PTB and TDL.

Pulmonary Hypertension With Interstitial Pneumonia: Initial Treatment Effectiveness and Severity in a Japan Registry

Background

Recent guidelines discourage the use of pulmonary arterial hypertension (PAH)-targeted therapies in patients with pulmonary hypertension (PH) associated with respiratory diseases. Therefore, stratifications of the effectiveness of PAH-targeted therapies are important for this group.

Objectives

The authors aimed to identify phenotypes that might benefit from initial PAH-targeted therapies in patients with PH associated with interstitial pneumonia and combined pulmonary fibrosis and emphysema.

Methods

We categorized 270 patients with precapillary PH (192 interstitial pneumonia, 78 combined pulmonary fibrosis and emphysema) into severe and mild PH using a pulmonary vascular resistance of 5 WU. We investigated the prognostic factors and compared the prognoses of initial (within 2 months after diagnosis) and noninitial treatment groups, as well as responders (improvements in World Health Organization functional class, pulmonary vascular resistance, and 6-minute walk distance) and nonresponders.

Results

Among 239 treatment-naive patients, 46.0% had severe PH, 51.8% had mild ventilatory impairment (VI), and 40.6% received initial treatment. In the severe PH with mild VI subgroup, the initial treatment group had a favorable prognosis compared with the noninitial treatment group. The response rate in this group was significantly higher than the others (48.2% vs 21.8%, ratio 2.21 [95% CI: 1.17-4.16]). In multivariate analysis, initial treatment was a better prognostic factor for severe PH but not for mild PH. Within the severe PH subgroup, responders had a favorable prognosis.

Conclusions

This study demonstrated an increased number of responders to initial PAH-targeted therapy, with a favorable prognosis in severe PH cases with mild VI. A survival benefit was not observed in mild PH cases. (Multi-institutional Prospective Registry in Pulmonary Hypertension associated with Respiratory Disease; UMIN000011541).