Registry and Survival Study in Chinese Patients With Idiopathic and Familial Pulmonary Arterial Hypertension

Prognostic impact of right atrial strain in systemic lupus erythematosus with pulmonary arterial hypertension

OBJECTIVE

The aim of this study was to assess right atrial (RA) function, including RA phase strain, via speckle-tracking echocardiography (STE) in a cohort of systemic lupus erythematosus (SLE) patients with pulmonary arterial hypertension (PAH) and in particular to explore the relationship between RA phase strain and the occurrence of cardiovascular events.

METHODS

STE analyses of RA function were evaluated in patients with SLE-PAH and in 33 healthy control subjects. Clinical associations, serum biomarkers, echocardiographic data, survival times, and adverse cardiovascular events were evaluated.

RESULTS

A total of 66 patients with SLE-PAH were enrolled; they were divided into two groups based on the occurrence of adverse clinical events. RA phase strain was significantly reduced in patients with events than in patients without events. The endpoint was defined as the combined outcome of all-cause mortality, right heart failure, and rehospitalization due to disease progression. During a mean follow-up of 17.2 ± 9.9 months, 23 patients (35%) reached the endpoint. Compared with patients with RA reservoir strain (RASr) ≥33.45%, patients with RASr < 33.45% had more adverse long-term outcomes (log rank p < .0001). RASr was independently associated with adverse clinical outcomes according to multivariate analysis (p = .010).

CONCLUSION

Our data suggest that RA function has prognostic value for SLE-PAH patients, and strain analysis revealed that the worse the RA function is, the worse the prognosis.

Real-world effectiveness and safety of macitentan in patients with pulmonary artery hypertension: a multicenter, retrospective, observational study in China

BACKGROUND

Macitentan, either as monotherapy or part of combination therapy, improved clinical outcomes in patients with pulmonary artery hypertension (PAH) in clinical trials. Evidence on the effectiveness and safety of macitentan administered in real-world clinical practice in China is limited.

METHODS

This real-world, retrospective, multicenter chart review study was conducted at seven hospitals in China. Adult patients with a diagnosis of PAH who initiated macitentan and had medical assessments at 3-7 months after macitentan initiation were included. The primary outcomes were changes in the World Health Organization functional class (WHO-FC), 6-min walk distance (6MWD), and N-terminal pro-B-type natriuretic peptide (NT-proBNP)/B-type natriuretic peptide from baseline to first follow-up visit (months 3-7). Serious adverse events (SAEs) and adverse drug reactions (ADRs) of macitentan were collected.

RESULTS

From 30 August 2021 to 31 March 2022, 214 eligible patients were included in the safety analysis set and 105 patients were included in the analysis of effectiveness. At the first follow-up visit compared with baseline, significant changes in WHO-FC were observed (p = .04), 93.5% patients had their WHO-FC improved (25.8%) or maintained (67.7%). 6MWD changed by a mean (standard deviation [SD]) of 45.0 (81.4) meters (p < .001), with 94.7% having their 6MWD improved (34.7%) or maintained (60.0%). The mean (SD) of NT-proBNP decreased from 1667.4 (3233.0) ng/L to 1090.0 (2230.1) ng/L (p < .001). In the safety analysis set, 24 (11.2%) patients experienced at least one ADR and/or SAE. ADRs and SAEs were reported in 11 (5.1%) and 18 (8.4%), respectively. No deaths or unexpected safety events were observed.

CONCLUSION

This study provided real-world evidence on the clinical benefits and good tolerance of macitentan in Chinese patients with PAH treated in routine clinical practice.

Prevalence, patient characteristics and treatment patterns among systemic lupus erythematosus-pulmonary arterial hypertension patients in real-world clinical practice: A retrospective analysis of Medical Data Vision Database in Japan

OBJECTIVES

Real-world evidence regarding prevalence, patient characteristics, and treatment patterns for pulmonary arterial hypertension (PAH) related to systemic lupus erythematosus (SLE) in Japan is limited.

METHODS

We conducted a retrospective study analysing Japan's Medical Data Vision database from April 2008 to September 2020. Prevalence, incidence, patient characteristics, treatment patterns, and use of vasodilators by treatment line were evaluated.

RESULTS

The prevalence of PAH was 0.392% in SLE patients (n = 114/29,077). Cumulative incidence was 0.53% (3 years) and 0.77% (5 years). Of 114 SLE-PAH patients, 49% developed PAH <1 year from SLE diagnosis. SLE-PAH patients were predominantly females (88% vs. 72%), had a lower mean age at SLE diagnosis (53 vs. 56 years), and had more severe SLE (61% vs. 25%) than non-PAH-SLE patients. Glucocorticoids (58%) and vasodilators (27%) were preferred first-line monotherapy for SLE-PAH. A combination of glucocorticoids and immunosuppressants (19%) was the predominant first-line combination therapy. Endothelin receptor antagonists (40% and 44%) and nitric oxide analogues (31% and 40%) were dominant first- and second-line vasodilators.

CONCLUSIONS

SLE-PAH patients were predominantly females, were younger at diagnosis, and had more severe SLE than non-PAH-SLE patients. Most were diagnosed <1 year of SLE diagnosis. In Japan's real-world practice, the initial treatment goal is SLE management, while vasodilators are preferred in advanced diseases, as per the Medical Data Vision database.

A Single Center Experience of Pulmonary Arterial Hypertension Management in Korea: A 25-Year Comparative Analysis Following the Introduction of Targeted Therapy

BACKGROUND AND OBJECTIVES

The transformation of pulmonary arterial hypertension (PAH) treatment in Korea, ushered by targeted therapy's advent, prompted our analysis of baseline attributes, treatment trends, and survival shifts within our single-center registry.

METHODS

We examined 230 patients (72.6% female, mean age 40.6±17.4 years) diagnosed and/or treated between 1980 and 2021 in our PAH clinic. Given targeted therapy's introduction and active use since 2007, we compared diagnostic classification, demographics, and treatment patterns at that juncture. Survival analysis encompassed PAH types and the overall population. For historical survival comparison, 50 non-registry patients were retrospectively added, and age-sex matching enabled pooled analysis.

RESULTS

Congenital heart disease-associated pulmonary arterial hypertension (CHD-PAH) constituted the largest subset (43.0%), trailed by connective tissue disease-associated PAH (CTD-PAH, 29.6%) and idiopathic PAH (IPAH, 19.1%). Post-2007, CTD-PAH proportions surged, notably with an elevated initiation rate of targeted therapy (95.4%). Overall survival rates at 1, 5, and 10 years stood at 91.3%, 77.4%, and 65.8%, respectively, with CHD-PAH exhibiting superior survival to idiopathic or CTD-PAH. Age-sex matching analysis indicated survival disparities between those starting immediate targeted therapy vs. conservative treatment upon diagnosis, especially driven by IPAH.

CONCLUSIONS

In the post-introduction of the targeted therapy era, patients with PAH promptly started treatment right away, and higher survival rates of patients who started initial PAH-targeted therapy were demonstrated. The transition towards early treatment initiation might have likely contributed to the elevated survival rates observed in Korea's PAH patient cohort.

Association of non-insulin-based insulin resistance indices with disease severity and adverse outcome in idiopathic pulmonary arterial hypertension: a multi-center cohort study

BACKGROUND

Insulin resistance (IR) plays an important role in the pathophysiology of cardiovascular disease. Recent studies have shown that diabetes mellitus and impaired lipid metabolism are associated with the severity and prognosis of idiopathic pulmonary arterial hypertension (IPAH). However, the relationship between IR and pulmonary hypertension is poorly understood. This study explored the association between four IR indices and IPAH using data from a multicenter cohort.

METHODS

A total of 602 consecutive participants with IPAH were included in this study between January 2015 and December 2022. The metabolic score for IR (METS-IR), triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio, triglyceride and glucose (TyG) index, and triglyceride-glucose-body mass index (TyG-BMI) were used to quantify IR levels in patients with IPAH. The correlation between non-insulin-based IR indices and long-term adverse outcomes was determined using multivariate Cox regression models and restricted cubic splines.

RESULTS

During a mean of 3.6 years' follow-up, 214 participants experienced all-cause death or worsening condition. Compared with in low to intermediate-low risk patients, the TG/HDL-C ratio (2.9 ± 1.7 vs. 3.3 ± 2.1, P = 0.003) and METS-IR (34.5 ± 6.7 vs. 36.4 ± 7.5, P < 0.001) were significantly increased in high to intermediate-high risk patients. IR indices correlated with well-validated variables that reflected the severity of IPAH, such as the cardiac index and stroke volume index. Multivariate Cox regression analyses indicated that the TyG-BMI index (hazard ratio [HR] 1.179, 95% confidence interval [CI] 1.020, 1.363 per 1.0-standard deviation [SD] increment, P = 0.026) and METS-IR (HR 1.169, 95% CI 1.016, 1.345 per 1.0-SD increment, P = 0.030) independently predicted adverse outcomes. Addition of the TG/HDL-C ratio and METS-IR significantly improved the reclassification and discrimination ability beyond the European Society of Cardiology (ESC) risk score.

CONCLUSIONS

IR is associated with the severity and long-term prognosis of IPAH. TyG-BMI and METS-IR can independently predict clinical worsening events, while METS-IR also provide incremental predictive performance beyond the ESC risk stratification.

Vaccination against coronavirus disease 2019 in patients with pulmonary hypertension: A national prospective cohort study

BACKGROUND

Coronavirus disease 2019 (COVID-19) has potential risks for both clinically worsening pulmonary hypertension (PH) and increasing mortality. However, the data regarding the protective role of vaccination in this population are still lacking. This study aimed to assess the safety of approved vaccination for patients with PH.

METHODS

In this national prospective cohort study, patients diagnosed with PH (World Health Organization [WHO] groups 1 and 4) were enrolled from October 2021 to April 2022. The primary outcome was the composite of PH-related major adverse events. We used an inverse probability weighting (IPW) approach to control for possible confounding factors in the baseline characteristics of patients.

RESULTS

In total, 706 patients with PH participated in this study (mean age, 40.3 years; mean duration after diagnosis of PH, 8.2 years). All patients received standardized treatment for PH in accordance with guidelines for the diagnosis and treatment of PH in China. Among them, 278 patients did not receive vaccination, whereas 428 patients completed the vaccination series. None of the participants were infected with COVID-19 during our study period. Overall, 398 patients received inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine, whereas 30 received recombinant protein subunit vaccine. After adjusting for baseline covariates using the IPW approach, the odds of any adverse events due to PH in the vaccinated group did not statistically significantly increase (27/428 [6.3%] vs. 24/278 [8.6%], odds ratio = 0.72, P = 0.302). Approximately half of the vaccinated patients reported at least one post-vaccination side effects, most of which were mild, including pain at the injection site (159/428, 37.1%), fever (11/428, 2.6%), and fatigue (26/428, 6.1%).

CONCLUSIONS

COVID-19 vaccination did not significantly augment the PH-related major adverse events for patients with WHO groups 1 and 4 PH, although there were some tolerable side effects. A large-scale randomized controlled trial is warranted to confirm this finding. The final approval of the COVID-19 vaccination for patients with PH as a public health strategy is promising.

Hemodynamic and Clinical Profiles of Pulmonary Arterial Hypertension Patients with GDF2 and BMPR2 Variants

Asians have a higher carrier rate of pulmonary arterial hypertension (PAH)-related genetic variants than Caucasians do. This study aimed to identify PAH-related genetic variants using whole exome sequencing (WES) in Asian idiopathic and heritable PAH cohorts. A WES library was constructed, and candidate variants were further validated by polymerase chain reaction and Sanger sequencing in the PAH cohort. In a total of 69 patients, the highest incidence of variants was found in the BMPR2, ATP13A3, and GDF2 genes. Regarding the BMPR2 gene variants, there were two nonsense variants (c.994C>T, p. Arg332*; c.1750C>T, p. Arg584*), one missense variant (c.1478C>T, p. Thr493Ile), and one novel in-frame deletion variant (c.877_888del, p. Leu293_Ser296del). Regarding the GDF2 variants, there was one likely pathogenic nonsense variant (c.259C>T, p. Gln87*) and two missense variants (c.1207G>A, p. Val403Ile; c.38T>C, p. Leu13Pro). The BMPR2 and GDF2 variant subgroups had worse hemodynamics. Moreover, the GDF2 variant patients were younger and had a significantly lower GDF2 value (135.6 ± 36.2 pg/mL, p = 0.002) in comparison to the value in the non-BMPR2/non-GDF2 mutant group (267.8 ± 185.8 pg/mL). The BMPR2 variant carriers had worse hemodynamics compared to the patients with the non-BMPR2/non-GDF2 mutant group. Moreover, there was a significantly lower GDF2 value in the GDF2 variant carriers compared to the control group. GDF2 may be a protective or corrected modifier in certain genetic backgrounds.

Prevalence and Determinants of Delay in Time-to-Diagnosis for Pulmonary Arterial Hypertension Patients in Gansu China: A Observational Cohort Study

Current studies of patients with pulmonary arterial hypertension (PAH) have shown a significant diagnostic delay. However, the causes and risk factors for this delay are not been well explored in Chinese population. This study aimed to assess the status of diagnostic delay in patients with PAH in China. Additionally, we identified factors associated with the delay. Demographic and clinical data were collected from 153 PAH patients admitted to three tertiary hospitals in Gansu, China, from March 2020 to October 2022. Based on the recorded date, the diagnostic delay was divided into patient delay and health system delay. For analysis, we divided diagnostic delay into 2 groups (≤3 years and >3 years). Factors associated with delay were identified by binary logistic regression. The median diagnostic delay was 3 years (IQR: 0.25-5.88). Binary logistic regression analysis showed that male (OR = 2.48, 95% CI: 1.10-5.58), those with junior high school or below (OR = 3.65, 95% CI: 1.36-9.78), living far away from the tertiary hospital (OR = 2.66, 95% CI: 1.14-6.18), initially visit hospital before 2018 (OR = 3.82, 95% CI: 1.68-8.71), and visit hospital at county level or below (OR = 3.80, 95% CI: 1.42-10.18) were risk factor for diagnostic delay (>3 years). Despite increased awareness, most patients with PAH in Gansu, China still experienced a delay in diagnosis of more than 3 years. Male sex, lower educational background, and being away from tertiary hospitals are risk factors for delay. Furthermore, factors impacting time-to-diagnosis and its impact should be continuously evaluated as therapeutic strategies continue to evolve and improve.

Assessment of Knowledge, Attitude, and Practice Patterns in Pulmonary Arterial Hypertension among Cardiologists and Pulmonologists: Evidence from Turkey

Background and Objectives: Pulmonary arterial hypertension (PAH) is a rare chronic disease of the small pulmonary arteries that causes right heart failure and death. Accurate management of PAH is necessary to decrease morbidity and mortality. Understanding current practices and perspectives on PAH is important. For this purpose, we intended to determine physicians' knowledge, attitudes, and practice patterns in adult pulmonary arterial hypertension (PAH) in Turkey. Materials and Methods: Between January and February 2022, an online questionnaire was sent via e-mail to all cardiologists and pulmonologists who were members of the Turkish Society of Cardiology (TSC) and the Turkish Thoracic Society (TTS). Results: A total of 200 physicians (122 pulmonologists and 78 cardiologists) responded to the questionnaire. Cardiologists were more frequently involved in the primary diagnosis and treatment of PAH than pulmonologists (37.2% vs. 23.8%, p = 0.042). More than half of the physicians had access to right heart catheterization. In mild/moderate PAH patients with a negative vasoreactivity test, the monotherapy option was most preferred (82.8%) and endothelin receptor antagonists (ERAs) were the most preferred group in these patients (73%). ERAs plus phosphodiesterase-5 inhibitors (PDE-5 INH) were the most preferred (69%) combination therapy, and prostacyclin analogues plus PDE-5 INH was preferred by only pulmonologists. Conclusions: Overall, clinical management of patients with PAH complied with guideline recommendations. Effective clinical management of PAH in specialized centers that having right heart catheterization achieve better outcomes.

Real-world evidence to advance knowledge in pulmonary hypertension: Status, challenges, and opportunities. A consensus statement from the Pulmonary Vascular Research Institute's Innovative Drug Development Initiative's Real-world Evidence Working Group

This manuscript on real-world evidence (RWE) in pulmonary hypertension (PH) incorporates the broad experience of members of the Pulmonary Vascular Research Institute's Innovative Drug Development Initiative Real-World Evidence Working Group. We aim to strengthen the research community's understanding of RWE in PH to facilitate clinical research advances and ultimately improve patient care. Herein, we review real-world data (RWD) sources, discuss challenges and opportunities when using RWD sources to study PH populations, and identify resources needed to support the generation of meaningful RWE for the global PH community.

Pulmonary hypertension in remote and disadvantaged population: overcoming unique challenges for improved outcomes

Pulmonary hypertension (PH) is a common and debilitating medical condition with high mortality. PH research has traditionally focused on pulmonary arterial hypertension and its management in expert PH centres. Other forms of PH such as PH associated with cardiac or respiratory disease are more common, less well-understood and associated with higher mortality. Epidemiology of PH in disadvantaged, remote and rural regions, remains largely undocumented. In this review, we discuss the unique challenges in identifying PH in rural and disadvantaged populations using the Top End region of the Northern Territory of Australia as an example. We propose a simple diagnostic approach, ideally suited to regions where resource allocation is scarce, using clinical skills, echocardiography, and an escalation algorithm. The brief history, epidemiology and current literature on PH are summarised to inform the busy clinicians. We highlight two case examples from the Top End to illustrate the challenges and potential solutions.

Epidemiology of PAH in Korea: An Analysis of the National Health Insurance Data, 2002–2018

BACKGROUND AND OBJECTIVES

Pulmonary arterial hypertension (PAH) is a rare but fatal disease. Recent advances in PAH-specific drugs have improved its outcomes, although the healthcare burden of novel therapeutics may lead to a discrepancy in outcomes between developing and developed countries. We analyzed how the epidemiology and clinical features of PAH has changed through the rapidly advancing healthcare infrastructure in South Korea.

METHODS

PAH was defined according to a newly devised 3-component algorithm. Using a nationwide health insurance claims database, we delineated annual trends in the prevalence, incidence, medication prescription pattern, and 5-year survival of PAH in Korea. Cumulative survival and potential predictors of mortality were also assessed among 2,151 incident PAH cases.

RESULTS

Between 2002 or 2004 and 2018, the prevalence and incidence of PAH increased 75-fold (0.4 to 29.9 per million people) and 12-fold (0.5 to 6.3 per million person-years), respectively. The proportion of patients on combination PAH-specific drug therapy has also steadily increased up to 29.0% in 2018. Among 2,151 incident PAH cases (median [interquartile range] age, 50 [37-62] years; 67.2% female), the 5-year survival rate and median survival duration were 71.8% and 13.1 years, respectively. Independent predictors of mortality were age, sex, etiology of PAH, diabetes, dyslipidemia, and chronic kidney disease.

CONCLUSIONS

This nationwide study delineated that the prevalence and incidence of PAH have grown rapidly in Korea since the early 2000s. The use of combination therapy has also increased, and the 5-year survival rate of PAH in Korea was similar to those in western countries.

Real-world evidence of subcutaneous treprostinil use in pulmonary arterial hypertension in Argentina

INTRODUCTION

Pulmonary arterial hypertension is a progressive haemodynamic disease with high morbidity and mortality. Of the different treatments available, the prostacyclin analogues are the drugs of choice for high-risk patients, with treprostinil being the most commonly used drug in Argentina.

METHODOLOGY

The objective of this study is to perform a retrospective evaluation of the efficacy and safety of subcutaneous treprostinil in regular clinical practice in Argentina in 51 patients with pulmonary arterial hypertension after 12 months of follow-up.

RESULTS

The results showed that treatment with subcutaneous treprostinil is associated with a significant improvement in different clinical efficacy parameters: 65% reduction in advanced functional class (p < 0.0001), 130-m increase in the 6-min walk test (p < 0.0001), 65% reduction in the pro B-type natriuretic peptide value (-531 pg/dL; p < 0.0001), significant reduction of 15.7% in pulmonary vascular resistance [-1.3 wood units (WU); p < 0.0001], improved cardiac index with an increase of 16.7% (+0.4 L/min/m²; p = 0.002), as well as a high survival rate (92%) and a 44% incidence of combined events (mortality, heart failure, syncope and/or lung transplantation), without a significant increase in previously reported adverse events. The risk stratification evaluation according to ESC/ERS guidelines showed a significant decrease in the proportion of patients at high risk after the treatment period (p = 0.004).

CONCLUSIONS

These real-world results corroborate the efficacy and safety of subcutaneous treprostinil, even at high doses, and open up the possibility of improving its current use in clinical practice as a first-line therapy, especially in high-risk patient profiles.

Native T1 Mapping-Based Radiomics for Noninvasive Prediction of the Therapeutic Effect of Pulmonary Arterial Hypertension

(1) Background: Novel markers for predicting the short-term therapeutic effect of pulmonary arterial hypertension (PAH) to assist in the prompt initiation of tailored treatment strategies are greatly needed and highly desirable. The aim of the study was to investigate the role of cardiac magnetic resonance (CMR) native T1 mapping radiomics in predicting the short-term therapeutic effect in PAH patients; (2) Methods: Fifty-five PAH patients who received targeted therapy were retrospectively included. Patients were subdivided into an effective group and an ineffective group by assessing the therapeutic effect after ≥3 months of treatment. All patients underwent CMR examinations prior to the beginning of the therapy. Radiomics features from native T1 mapping images were extracted. A radiomics model was constructed using the support vector machine (SVM) algorithm for predicting the therapeutic effect; (3) Results: The SVM radiomics model revealed favorable performance for predicting the therapeutic effect with areas under the receiver operating characteristic curve of 0.955 in the training cohort and 0.893 in the test cohort, respectively. With the optimal cutoff value, the radiomics model showed accuracies of 0.909 and 0.818 in the training and test cohorts, respectively; (4) Conclusions: The CMR native T1 mapping-based radiomics model holds promise for predicting the therapeutic effect in PAH patients.

Pulmonary Hypertension Definition, Classification, and Epidemiology in Asia

Pulmonary hypertension (PH) is caused by a range of conditions and is important to recognize as it is associated with increased mortality. Pulmonary arterial hypertension refers to a group of PH subtypes affecting the distal pulmonary arteries for which effective treatment is available. The hemodynamic definition of pulmonary arterial hypertension has recently changed which may lead to greater case recognition and earlier treatment. The prevalence of specific PH etiologies may differ depending on geographic region. PH caused by left heart disease is the most common cause of PH worldwide. In Asia, there is greater proportion of congenital heart disease- and connective tissue disease- (especially systemic lupus erythematosus) related PH relative to the West. This review summarizes the definition, classification, and epidemiology of PH as it pertains to Asia.

Role of miR-21-5p/FilGAP axis in estradiol alleviating the progression of monocrotaline-induced pulmonary hypertension

Background

Aberrant expression of microRNAs (miRNAs) has been associated with the pathogenesis of pulmonary hypertension (PH). It is, however, not clear whether miRNAs are involved in estrogen rescue of PH.

Methods

Fresh plasma samples were prepared from 12 idiopathic pulmonary arterial hypertension (IPAH) patients and 12 healthy controls undergoing right heart catheterization in Shanghai Pulmonary Hospital. From each sample, 5 μg of total RNA was tagged and hybridized on microRNA microarray chips. Monocrotaline‐induced PH (MCT‐PH) male rats were treated with 17β‐estradiol (E₂) or vehicle. Subgroups were cotreated with estrogen receptor (ER) antagonist or with antagonist of miRNA.

Results

Many circulating miRNAs, including miR‐21‐5p and miR‐574‐5p, were markedly expressed in patients and of interest in predicting mean pulmonary arterial pressure elevation in patients. The expression of miR‐21‐5p in the lungs was significantly upregulated in MCT‐PH rats compared with the controls. However, miR‐574‐5p showed no difference in the lungs of MCT‐PH rats and controls. miR‐21‐5p was selected for further analysis in rats as E₂ strongly regulated it. E₂ decreased miR‐21‐5p expression in the lungs of MCT‐PH rats by ERβ. E₂ reversed miR‐21‐5p target gene FilGAP downregulation in the lungs of MCT‐PH rats. The abnormal expression of RhoA, ROCK2, Rac1 and c‐Jun in the lungs of MCT‐PH rats was inhibited by E₂ and miR‐21‐5p antagonist.

Conclusions

miR‐21‐5p level was remarkably associated with PH severity in patients. Moreover, the miR‐21‐5p/FilGAP signaling pathway modulated the protective effect of E₂ on MCT‐PH through ERβ.

Clinical Characteristics and Transplant-Free Survival Across the Spectrum of Pulmonary Vascular Disease

BACKGROUND

PVDOMICS (Pulmonary Vascular Disease Phenomics) is a precision medicine initiative to characterize pulmonary vascular disease (PVD) using deep phenotyping. PVDOMICS tests the hypothesis that integration of clinical metrics with omic measures will enhance understanding of PVD and facilitate an updated PVD classification.

OBJECTIVES

The purpose of this study was to describe clinical characteristics and transplant-free survival in the PVDOMICS cohort.

METHODS

Subjects with World Symposium Pulmonary Hypertension (WSPH) group 1-5 PH, disease comparators with similar underlying diseases and mild or no PH and healthy control subjects enrolled in a cross-sectional study. PH groups, comparators were compared using standard statistical tests including log-rank tests for comparing time to transplant or death.

RESULTS

A total of 1,193 subjects were included. Multiple WSPH groups were identified in 38.9% of PH subjects. Nocturnal desaturation was more frequently observed in groups 1, 3, and 4 PH vs comparators. A total of 50.2% of group 1 PH subjects had ground glass opacities on chest computed tomography. Diffusing capacity for carbon monoxide was significantly lower in groups 1-3 PH than their respective comparators. Right atrial volume index was higher in WSPH groups 1-4 than comparators. A total of 110 participants had a mean pulmonary artery pressure of 21-24 mm Hg. Transplant-free survival was poorest in group 3 PH.

CONCLUSIONS

PVDOMICS enrolled subjects across the spectrum of PVD, including mild and mixed etiology PH. Novel findings include low diffusing capacity for carbon monoxide and enlarged right atrial volume index as shared features of groups 1-3 and 1-4 PH, respectively; unexpected, frequent presence of ground glass opacities on computed tomography; and sleep alterations in group 1 PH, and poorest survival in group 3 PH. PVDOMICS will facilitate a new understanding of PVD and refine the current PVD classification. (Pulmonary Vascular Disease Phenomics Program PVDOMICS [PVDOMICS]; NCT02980887).

Decreased low‑density lipoprotein and the presence of pulmonary arterial hypertension among newly diagnosed drug‑naïve patients with systemic lupus erythematosus: D‑dimer as a mediator

Pulmonary arterial hypertension (PAH) is commonly associated with systemic lupus erythematosus (SLE). The present study investigated the relationship between coagulation and changes in lipid parameters in newly-diagnosed patients with SLE in the presence of PAH and whether the coagulation parameters were mediators between lipids and PAH presence. A total of 301 subjects scheduled for new-onset drug-naïve SLE were consecutively enrolled. Baseline data for patients without PAH and with PAH were gathered and compared. Coagulation and lipid parameters were compared across patients without lipid regulating and anticoagulation medications. Multivariable logistic regression model was applied to examine potential predictors of PAH in SLE. The relationships between them were examined using Spearman's correlation analysis. The relationship between coagulation index and lipids with SLE-PAH was evaluated using mediation analysis. Female patients accounted for 88.0% of the 301 subjects, and the average age was 32 years (range, 25-45 years). A total of 40 patients (13.3%) had PAH, and the average pulmonary artery systolic pressure (sPAP) was 55.825±26.67 mmHg. Patients with PAH were older and had higher levels of fibrin/fibrinogen degradation products (FDP), D-dimer, C-reactive protein, lower levels of complement 3, complement 4 and 25-hydroxy vitamin D3 compared with the non-PAH group. Multivariable logistic regression analysis showed that age and D-dimer were independent predictor factors for PAH. Among patients without lipid regulating and anticoagulation medications, patients in the PAH group had higher levels of D-dimer and FDP, and lower low-density lipoprotein (LDL) levels compared with patients without PAH. There was also a positive relationship between sPAP and D-dimer and FDP, and a negative relationship between sPAP and total cholesterol and LDL. Mediation analysis indicated that 25.61% of the effect of low LDL on PAH presence in systemic lupus erythematosus was mediated by D-dimer. Overall, the effect of low LDL on SLE-PAH appeared to be mediated by D-dimer, which mediated 25.61% of this effect.

Characteristics, goal-oriented treatments and survival of pulmonary arterial hypertension in China: Insights from a national multicentre prospective registry

BACKGROUND AND OBJECTIVE

Nationally representative reports on the characteristics and long-term survival of pulmonary arterial hypertension (PAH) from developing countries are scarce. The applicability of the current main risk stratifications and the longitudinal changes in goal-oriented treatments have yet to be elucidated in real-world settings. Therefore, we aimed to provide insights into the characteristics, goal-oriented treatments and survival of PAH in China and to explore the applicability of the main risk stratifications in our independent cohort.

METHODS

PAH patients were consecutively enrolled from a national prospective multicentre registry. Data on baseline, follow-up re-evaluation and therapeutic changes were collected.

RESULTS

A total of 2031 patients were enrolled, with congenital heart disease (CHD)-PAH (45.2%) being the most common aetiology. The mean age was 35 ± 12 years, and 76.2% were females. At baseline, approximately 20% of the patients with intermediate or high risk received combination treatment. At follow-up, approximately half of the re-evaluated patients did not achieve low-risk profiles, and even among patients who received combination therapy at baseline, 4% of them still worsened. The rate of combination therapy increased significantly from 6.7% before 2015 to 35.5% thereafter. The main risk assessment tools demonstrated good performance for predicting survival both at baseline and at follow-up.

CONCLUSION

Chinese PAH patients show both similar and distinct features compared to other countries. Current main risk stratifications can significantly discriminate patients at different risk levels. There were still many patients not achieving low-risk profiles at follow-up, indicating more aggressive treatment should be implemented to optimize the goal-oriented treatment strategy.

Echocardiography Nomogram for Predicting Survival among Chronic Lung Disease Patients with Severe Pulmonary Hypertension

Severe pulmonary hypertension in chronic lung diseases (severe CLD-PH) differs significantly from other types of PH in physiology and prognosis. We aimed to assess whether echocardiography helps predict long-term survival in patients with severe CLD-PH. This single-centre, observational cohort study enrolled 100 patients with severe CLD-PH (mean pulmonary arterial pressure ≥35 mm Hg or ≥25 mm Hg with cardiac index <2.0 L/min/m2 or pulmonary vascular resistance ≥6 Wood units) between 2009 and 2014. The population was randomly divided into a derivation and validation cohort in a 2:1 ratio. To construct a nomogram, a multivariable logistic regression model was applied, and scores were assigned based on the hazard ratio of independent echocardiographic predictors. Multivariate Cox hazards analysis identified the strongest predictors of mortality as pulmonary arterial systolic pressure (PASP), tricuspid annular plane systolic excursion, and right ventricular end-diastolic transverse dimension. The three independent predictors were entered into the nomogram. Compared with PASP alone, the nomogram resulted in an integrated discrimination improvement of 15.5% (95% confidence interval, 5.52−25.5%, p = 0.002) with a net improvement in model discrimination (C-statistic from 0.591 to 0.746). Using echocardiographic parameters, we established and validated a novel nomogram to predict all-cause death for patients with severe CLD-PH.

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.

Gene Mutation Annotation and Pedigree for Pulmonary Arterial Hypertension Patients in Han Chinese Patients

Background:

The etiology of pulmonary arterial hypertension (PAH) in the Han Chinese population is poorly understood.

Objectives:

The aim of this study was to assess gene variants and associated functional annotations for PAH in Han Chinese patients.

Methods:

This is an ethnicity-based multi-centre study. Blood samples were collected from 20 PAH patients who volunteered for the study, and genetic tests were performed. The DAVID database was used to functionally annotate the genes BMPR2, ALK1, KCNK3, CAV1, and ENG. Associated diseases, functional categories, gene ontology, and protein interactions were analysed using the Functional Annotation Tool in the DAVID database. GEO and ClinVar databases were also used for further comparison with gene mutations in our study.

Results:

PAH patient with gene mutations were female predominant except for a single male with a BMPR2 mutation. Locus variants in our study included ‘G410DfsX1’ in BMPR2, ‘ex7 L300P,’ ‘ex4 S110PfsX40,’ and ‘ex7 E295Afs96X’ in ALK1, ‘c.-2C>A (IVS1–2 C>A)’ in CAV1, and ‘ex8 D366Q’ in ENG were not found in the ClinVar database associated with PAH. In addition to BMP and TGF-β pathways, gene ontology of input genes in the DAVID database also included pathways associated with nitric oxide signaling and regulation.

Conclusions:

This Multi-centre study indicated that ‘G410DfsX1’ in BMPR2, ‘ex7 L300P,’ ‘ex4 S110PfsX40,’ ‘ex7 E295Afs96X’ in ALK1, ‘c.-2C>A (IVS1–2 C>A)’ in CAV1, and ‘ex8 D366Q’ in ENG were identified in Han Chinese patients with PAH. Females were more susceptible to PAH, and a relatively young age distribution was observed for patients with BMPR2 mutations.

Sex Differences, Estrogen Metabolism and Signaling in the Development of Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a complex and devastating disease with a poor long-term prognosis. While women are at increased risk for developing PAH, they exhibit superior right heart function and higher survival rates than men. Susceptibility to disease risk in PAH has been attributed, in part, to estrogen signaling. In contrast to potential pathological influences of estrogen in patients, studies of animal models reveal estrogen demonstrates protective effects in PAH. Consistent with this latter observation, an ovariectomy in female rats appears to aggravate the condition. This discrepancy between observations from patients and animal models is often called the "estrogen paradox." Further, the tissue-specific interactions between estrogen, its metabolites and receptors in PAH and right heart function remain complex; nonetheless, these relationships are essential to characterize to better understand PAH pathophysiology and to potentially develop novel therapeutic and curative targets. In this review, we explore estrogen-mediated mechanisms that may further explain this paradox by summarizing published literature related to: (1) the synthesis and catabolism of estrogen; (2) activity and functions of the various estrogen receptors; (3) the multiple modalities of estrogen signaling in cells; and (4) the role of estrogen and its diverse metabolites on the susceptibility to, and progression of, PAH as well as their impact on right heart function.

Liver dysfunction in idiopathic pulmonary arterial hypertension: prevalence, characteristics and prognostic significance, a retrospective cohort study in China

OBJECTIVES

The aim was to elucidate the relationship between liver function and idiopathic pulmonary arterial hypertension (IPAH).

DESIGN AND SETTING

Retrospective, longitudinal study in urban tertiary care centre in Shanghai, China.

PARTICIPANTS

407 IPAH consecutive incident patients age 18-65 years were retrospectively enrolled from January 2008 to December 2018.

OUTCOME MEASUREMENTS

The primary endpoint was all-cause mortality. The cut-off value was determined by receiver operating characteristic curve (ROC), which was validated by Cox proportional hazard model was internally validated by bootstrap analysis and used for survival analysis. The Cox model was (internally) validated and cross-validated areas under the curve (AUC) should be reported.

RESULTS

The prevalence of abnormal liver function tests (LFTs) at baseline was 77.6%. Hyperbilirubinaemia is the most common abnormal biochemical liver test: abnormal total bilirubin (TBIL in 51.6% patients). During the follow-up, 160 patients died. Patients with mixed liver dysfunction have worse prognosis than those with normal LFTs or isolated abnormal bilirubin metabolism. Comparing with patients with hepatocellular injury, the survival of patients with abnormal bilirubin metabolism is lower. Multivariable Cox models revealed a positive association between TBIL, γ-glutamyltransferase (GGT) and mortality showing that each Ig increment in TBIL and GGT was associated with a higher all-cause mortality (TBIL: HR 4. 29 (95% CI 1. 21 to 15. 27), p=0. 02; GGT: HR 2. 76 (95% CI 1. 18 to 6. 45), p=0. 02). A novel formula named Liver Function Predict Index (LFPI) was constructed (LFPI=-0.002*6MWD+1.014*lg GGT+1.458*lg TBIL) to predict prognosis. ROC curve analysis did further identify 2.729 as the best cut-off value for LFPI (AUC 0.75, p<0.001, sensitivity 79%, specificity 70%).

CONCLUSIONS

Liver dysfunction is frequent in IPAH, and characterised by a predominantly cholestatic enzyme profile. LFTs abnormalities are associated with worse survival and LFPI was a new and simple predictor for prognosis of IPAH.

Repurposing of the PDE5 Inhibitor Sildenafil for the Treatment of Persistent Pulmonary Hypertension in Neonates

Nitric oxide (NO), an important endogenous signaling molecule released from vascular endothelial cells and nerves, activates the enzyme soluble guanylate cyclase to catalyze the production of cyclic guanosine monophosphate (cGMP) from guanosine triphosphate. cGMP, in turn, activates protein kinase G to phosphorylate a range of effector proteins in smooth muscle cells that reduce intracellular Ca²⁺ levels to inhibit both contractility and proliferation. The enzyme phosphodiesterase type 5 (PDE5) curtails the actions of cGMP by hydrolyzing it into inactive 5'-GMP. Small molecule PDE5 inhibitors (PDE5is), such as sildenafil, prolong the availability of cGMP and therefore, enhance NO-mediated signaling. PDE5is are the first-line treatment for erectile dysfunction but are also now approved for the treatment of pulmonary arterial hypertension (PAH) in adults. Persistent pulmonary hypertension in neonates (PPHN) is currently treated with inhaled NO, but this is an expensive option and around 1/3 of newborns are unresponsive, resulting in the need for alternative approaches. Here the development, chemistry and pharmacology of PDE5is, the use of sildenafil for erectile dysfunction and PAH, are summarized and then current evidence for the utility of further repurposing of sildenafil, as a treatment for PPHN, is critically reviewed.

Pulmonary hypertension in majority countries: opportunities amidst challenges

PURPOSE OF REVIEW

Pulmonary hypertension is a deadly disease, the causes of which vary between geographical regions. Eighty four percentage of the world's population lives in majority countries (also called low-income and middle-income countries), yet data on pulmonary hypertension in these settings are proportionally scarce. This article provides a review of pulmonary hypertension in majority countries, focusing in detail on the most common causes in these regions, and highlights contextual challenges faced.

RECENT FINDINGS

Epidemiological data confirms a complex and overlapping array of causes, with pulmonary hypertension because of conditions such as rheumatic heart disease, HIV, schistosomiasis, chronic lung disease and sickle cell disease. Delayed pulmonary hypertension diagnosis remains a concern and is ascribed to a lack of resources and lack of pulmonary hypertension awareness by health professionals. Pulmonary hypertension diagnosis is frequently considered once signs of right heart failure emerge, while echocardiography and right heart catheterization are unavailable in many settings. Accurate data on the prevalence of pulmonary hypertension in many of these regions are needed and could be achieved by establishing and frequent review of national databases where the incident and prevalent pulmonary hypertension cases are captured.

SUMMARY

There is urgent need for pulmonary hypertension advocacy among clinicians in the primary, secondary and tertiary healthcare sectors of majority countries, and validated noninvasive diagnostic algorithms are needed. Increased awareness and early diagnosis are likely to improve outcomes of pulmonary hypertension patients in these regions, and potentially stimulate locally relevant research.

2-Methoxyestradiol Attenuates the Development and Retards the Progression of Hypoxia-And Alpha-Naphthylthiourea-Induced Pulmonary Hypertension

Pulmonary arterial hypertension (PH), a progressive, incurable, and deadly disease, predominantly develops in women. Growing body of evidence suggest that dysregulated estradiol (E2) metabolism influences the development of PH and that some of the biological effects of E2 are mediated by its major non-estrogenic metabolite, 2-metyhoxyestradiol (2ME). The objective of this study was to examine effects of 2ME in chronic hypoxia (CH)-induced PH and alpha-naphthylthiourea (ANTU)-induced acute lung injury and PH. In addition, we investigated the effects of exposure to different levels of CH on development of PH. Chronic exposure to 15% or 10% oxygen produced similar increases in right ventricle peak systolic pressure (RVPSP) and pulmonary vascular remodeling, but oxygen concentration-dependent increase in hematocrit. Notably, right ventricle (RV) hypertrophy correlated with level of hypoxia and hematocrit, rather than with magnitude of RVPSP. The latter suggests that, in addition to increased afterload, hypoxia (via increased hematocrit) significantly contributes to RV hypertrophy in CH model of PH. In CH-PH rats, preventive and curative 2ME treatments reduced both elevated RVPSP and pulmonary vascular remodeling. Curative treatment with 2ME was more effective in reducing hematocrit and right ventricular hypertrophy, as compared to preventive treatment. Single ANTU injection produced lung injury, i.e., increased lungs weight and induced pleural effusion. Treatment with 2ME significantly reduced pleural effusion and, more importantly, eliminated acute mortality induced by ANTU (33% vs 0%, ANTU vs. ANTU+2ME group). Chronic treatment with ANTU induced PH and RV hypertrophy and increased lungs weight. 2-ME significantly attenuated severity of disease (i.e., reduced RVPSP, RV hypertrophy and pulmonary vascular injury). This study demonstrates that 2ME has beneficial effects in chronic hypoxia- and acute lung injury-induced PH and provides preclinical justification for clinical evaluation of 2ME in pulmonary hypertension.

Plasma exosomal miR-596: a novel biomarker predicts survival in patients with idiopathic pulmonary artery hypertension

Objective

To determine if plasma exosomal microRNAs (miRNAs) can predict survival in patients with idiopathic pulmonary arterial hypertension (IPAH).

Methods

The study enrolled patients with IPAH that underwent right heart catheterization. Plasma was collected and exosomal miRNAs were extracted. Exosomes were evaluated using transmission electron microscopy, Western blot analysis and particle size distribution analysis. MiRNAs were evaluated using a miRNA microarray and validated using real-time polymerase chain reaction.

Results

This study included 12 patients with IPAH in the study group and 48 patients with IPAH in the validation group. The mean ± SD follow-up duration was 60.3 ± 35.4 months in the overall cohort. The levels of miR-596 were higher in the nonsurvivors compared with the survivors. The levels of miR-596 significantly correlated with survival time, mean right atrial pressure, pulmonary vascular resistance (PVR) and cardiac index. High levels of miR-596 and PVR were significantly associated with poor overall survival. Multivariate analysis demonstrated that exosomal miR-596 (hazard ratio [HR] = 2.119; 95% confidence interval [CI] 1.402, 3.203) and PVR (HR = 1.146; 95% CI 1.010, 1.300) were independent predictors of survival.

Conclusions

High levels of plasma exosomal miR-596 were significantly associated with disease severity and poor prognosis of patients with IPAH.

Association of Rare PTGIS Variants With Susceptibility and Pulmonary Vascular Response in Patients With Idiopathic Pulmonary Arterial Hypertension

Question

What is the novel susceptibility gene for idiopathic pulmonary arterial hypertension?

Findings

In this 2-stage genetic association study of 230 patients with idiopathic pulmonary arterial hypertension, heterozygous rare PTGIS variants were first found significantly overrepresented in 6.1%, conferring 7.8 higher odds of pulmonary arterial hypertension. In addition, patients carrying rare PTGIS variants were more responsive to iloprost stimulation than those without such variants.

Meaning

The rare variants of the PTGIS gene appear to contribute higher susceptibility to idiopathic pulmonary arterial hypertension, and screening of PTGIS variants may help improve personalized treatment of these patients.

Importance

Idiopathic pulmonary arterial hypertension (IPAH) is a fatal disease with high heritability; however, the bone morphogenetic protein receptor 2 (BMPR2) gene only accounts for 17% of IPAH. The genetic basis of IPAH needs further investigation.

Objective

To identify novel IPAH susceptibility genes other than BMPR2.

Design, Setting, and Participants

This 2-stage, case-control genetic association study enrolled 230 patients with IPAH from 2 referral pulmonary hypertension centers in China. Eligible patients had no BMPR2 variants and were compared with 968 healthy control participants. Data were collected from January 1, 2000, to July 31, 2015, and analyzed from August 1, 2015, to May 30, 2018.

Exposures

PTGIS rare variants.

Main Outcomes and Measures

Whole-genome sequencing was performed to identify putative IPAH genes in a discovery cohort, with validation in an independent referral cohort. Correlation of genotype and hemodynamic characteristics was then evaluated at baseline and after pulmonary vasodilator testing. Functional assessments were conducted to analyze the effects of identified genetic variants on transcript splicing, enzymatic activity, and endothelial cell phenotypes.

Results

Among 230 patients with IPAH (164 female [71.3%]; mean [SD] age, 34 [18] years), an enrichment of rare variants in a gene encoding prostacyclin synthase (PTGIS) was identified in the discovery cohort. The association of PTGIS rare variants with IPAH was confirmed in the replication cohort. In the combined data set, PTGIS rare variants were found in 14 of 230 cases (6.1%) and 8 of 968 controls (0.8%) (odds ratio, 7.8; 95% CI, 3.2-18.8; P = 5 × 10⁻⁶, logistic regression). Compared with patients without PTGIS variants, inhaled iloprost induced a more significant decrease of pulmonary vascular resistance (difference in the least square mean, −21.7%; 95% CI, −31.4% to −12.0%; P < .001, linear regression model) and an increase of cardiac index (difference in the least square mean, 18.3%; 95% CI, 8.8%-27.8%; P < .001, linear regression model) in patients with PTGIS variants. The minigene assay indicated that the c.521 + 1G>A variant resulted in aberrant messenger RNA transcripts. The functional studies showed that the 2 missense rare variants (R252Q and A447T) resulted in a decrease in prostacyclin production and increased cell death of pulmonary microvascular endothelial cells.

Conclusions and Relevance

This study identified 3 rare loss-of-function variants in the PTGIS gene from 2 independent cohorts with IPAH. The genetic variants of PTGIS predispose pulmonary vascular responses to the iloprost stimulation. These findings suggest that PTGIS variants may be involved in the pathogenesis of IPAH.

Sjogren's Syndrome and Pulmonary Disease

Sjogren's syndrome is an autoimmune connective tissue disease targeting the exocrine glands and frequently affecting the respiratory system. The pulmonary disease is the most important extra-glandular manifestation as it carries most of the morbidity and mortality. Typically, it affects the small airways ranging from mild to severe respiratory symptoms. The upper airways are also commonly involved, predisposing sinusitis to occur more frequently than in the normal population. Lymphocytic interstitial pneumonia was initially thought to be the prevailing parenchymal disease; however, multiple cohorts report non-interstitial pneumonia to be the most frequent subtype of interstitial lung disease. In the review of high-resolution computed tomography scans, cystic lesions are commonly found and associate with both the small airways and parenchymal disease. Under their presence, amyloidosis or lymphomas should be considered in the differential. Overall, Sjogren's syndrome has a higher risk for lymphoma, and in lungs this condition should be thought of, especially when the images reveal pulmonary nodularity, lymphocytic interstitial pneumonia and lymphadenopathy. Although, pulmonary artery hypertension was traditionally and exceptionally linked with Sjogren's syndrome, together with systemic lupus erythematosus, they are now acknowledged to be the most common pulmonary vascular disease in east Asian populations, even over patients with systemic sclerosis. Although there are no controlled prospective trials to treat pulmonary disease in Sjogren's syndrome, the mainstay treatment modality still falls on glucocorticoid therapy (systemic and inhaled), combined with immune modulators or alone. Most of the evidence sustains successful outcomes based on reported cases or case series.

Long-term outcomes in pulmonary arterial hypertension by functional class: a meta-analysis of randomized controlled trials and observational registries

Limited data about the long-term prognosis and response to therapy in pulmonary arterial hypertension patients with World Health Organization functional class I/II symptoms are available. PubMed and Embase were searched for publications of observational registries and randomized, controlled trials in pulmonary arterial hypertension patients published between January 2001 and January 2018. Eligible registries enrolled pulmonary arterial hypertension patients ≥18 years, N > 30, and reported survival by functional class. Randomized, controlled trial inclusion criteria were pulmonary arterial hypertension patients ≥18 years, ≥6 months of treatment, and morbidity, mortality, or time to worsening as end points reported by functional class. The primary outcomes were survival for registries and clinical event rates for randomized, controlled trials. Separate random effects models were calculated for registries and randomized, controlled trials. Four randomized, controlled trials (n = 2482) and 10 registries (n = 6580) were included. Registries enrolled 9%–47% functional class I/II patients (the vast majority being functional class II) with various pulmonary arterial hypertension etiologies. Survival rates for functional class I/II patients at one, two, and three years were 93% (95% confidence interval (CI): 91%–95%), 86% (95% CI: 82%–89%), and 78% (95% CI: 73%–83%), respectively. The hazard ratio for the treatment effect in randomized, controlled trials overall was 0.61 (95% CI: 0.51–0.74) and 0.60 (95% CI: 0.44–0.82) for functional class I/II patients and 0.62 (95% CI: 0.49–0.78) for functional class III/IV. The calculated risk of death of 22% within three years for functional class I/II patients underlines the need for careful assessment and optimal treatment of patients with functional class I/II disease. The randomized, controlled trial analysis demonstrates that current medical therapies have a beneficial treatment effect in this population.

Increased Levels of Runt-Related Transcription Factor 2 Are Associated With Poor Survival of Patients With Idiopathic Pulmonary Arterial Hypertension

Runt-related transcription factor 2 (RUNX2) plays a pivotal role in the pathogenesis of pulmonary arterial hypertension (PAH); yet, whether circulating levels of RUNX2 can predict survival of patients with idiopathic PAH (IPAH) is still unclear. The present study aimed to investigate the correlation between circulating levels of RUNX2 and survival of patients with IPAH. Blood samples were collected from 46 incident patients with IPAH and 30 healthy controls in Shanghai Pulmonary Hospital. Levels of RUNX2 were measured using ELISA. Linear regression and cox proportional hazards analysis were performed to assess the prognostic value of RUNX2 levels in predicting survival using the Kaplan-Meier method. Nonsurvivors had significantly shorter 6MWD, higher levels of NT-proBNP, increased mRAP, mPAP, mPAWP, PVR, and decreased CO as well as CI, compared with survivors (p < .05). Plasma levels of RUNX2 were significantly higher in nonsurvival and survival patients with IPAH compared with controls (p ≤ .001), and higher in nonsurvivors than in survivors (p = .001). RUNX2 levels served as an independent predictor of survival in these patients (p < .001). RUNX2 levels ≥41.5 ng/ml had a sensitivity of 80.0% and a specificity of 74.2% by ROC analysis. Patients with a RUNX2 level <41.5 ng/ml and/or mRAP <3.5 mmHg had a significantly better prognosis than those with a higher RUNX2 level in all subjects as well as in male or female patients (p < .05). The level of circulating RUNX2 is an independent predictor for survival and it is correlated with the clinical severity of IPAH.

Prognostic value of six-minute walk distance at a South American pulmonary hypertension referral center

Six-minute walk distance (6MWD) assessment is recommended for pulmonary arterial hypertension multidimensional risk stratification. However, current 6MWD cut-off values were mainly derived from North American and European pulmonary arterial hypertension registries. Therefore, it is unknown if such cut-off values broadly apply to other geographical populations. In this study, we aimed to identify 6MWD cut-off values for Brazilian pulmonary arterial hypertension patients and to contrast our findings to current international Pulmonary Hypertension guidelines recommendations. One-hundred four consecutive pulmonary arterial hypertension patients were allocated in groups according to their 6MWD, considering 50 m as a clinically relevant 6MWD difference. Next, patients were categorized into different 6MWD ranges based on similar survival rates in each group: < 250 m, 250–400 m, and >400 m. The study outcome was all-cause mortality and transplantation according to the 6MWD range. Survival was truncated at five years. Median follow-up period was 4.35 years (0.48–5.00). Survival rates at 1, 2, 3, and 5 years were 96%, 89%, 81%, and 73%, respectively. Cox analyses adjusted for age, sex, and pulmonary arterial hypertension etiology showed that 6MWD < 250 m and >400 m were associated with higher and lower risk of all-cause mortality and transplantation. According to Harrell's c-statistic, the prognostic discrimination of the 6MWD cut-off value identified by the current study was 0.70 while international Pulmonary Hypertension guidelines 6MWD cut-offs value was 0.61. In conclusion, our findings suggest that 6MWD geographical variations should be considered when assessing risk stratification in pulmonary arterial hypertension.

miR-125a-5p inhibits glycolysis by targeting hexokinase-II to improve pulmonary arterial hypertension

Purpose: The aim of this study was to investigate the effect of microRNAs on the proliferation of pulmonary arterial smooth muscle cells (PASMCs) as a result of targeting hexokinase-II (HK-II) and its mechanism of action.

Results: Differences in metabolic patterns were found between the normal group and monocrotaline-induced pulmonary arterial hypertension (MCT-PH) group. miR-125a-5p decreased glycolysis levels of monocrotaline (MCT)-induced PASMCs by targeting HK-II and inhibiting its proliferation. In vivo experiments found that miR-125a-5p agomir upregulated HK-II expression in the MCT-PH. Right ventricular hypertrophy was reversed and cardiac function improved as a result of decreased mean pulmonary artery pressure (mPAP).

Conclusion: In vitro and in vivo experiments both confirmed that miR-125a-5p could inhibit cell glycolysis and PASMC proliferation to improve PAH by targeting HK-II.

Methods: HK-II overexpression was constructed, and differentially expressed microRNAs were screened for using microarrays. Serum metabolites were detected using Nuclear Magnetic Resonance (NMR). Through screening for characteristic metabolites in rat body fluids and by analyzing biological functions, disordered metabolic pathways were identified. Activity of the miR-125a-5p target HK-II was measured using a luciferase reporter assay. Expression of downstream molecules was measured by RT–qPCR and/or western blot. Glucose consumption and lactic acid production were analyzed and used as a reflection of glycolysis.

Effectiveness and safety of exercise training and rehabilitation in pulmonary hypertension: a systematic review and meta-analysis

Background

Pulmonary hypertension (PH) is a chronic progressive disease characterized by increasing pulmonary vascular resistance, poor prognosis and high disability rate. Although many targeted drugs for PH have been put to clinical use, most patients still have poor exercise tolerance and quality of life. Exercise training is considered to further improve exercise capacity and quality of life in patients with PH, but it has not been fully studied and utilized. The aim of this systematic review and meta-analysis is to evaluate the effectiveness and safety of exercise training in patients with PH.

Methods

A search was conducted for the meta-analysis using the databases PubMed, Embase, Cochrane Library, including literature published before December 2018. The primary outcome of this meta-analysis was a change in the 6-minute walk distance (6MWD). In addition, peak oxygen uptake (PeakVO₂), resting pulmonary arterial systolic pressure (PASP_rest), resting heart rate (HR_rest), peak exercise heart rate (HR_peak), oxygen uptake anaerobic threshold (VO₂ at AT), maximum workload and quality of life (QoL) were also assessed.

Results

A total of 651 patients in 17 studies were included. A meta-analysis showed that exercise training was associated with significant improvement in the 6MWD [weighted mean difference (WMD): 64.75 m (95% CI: 53.19–76.31 m, P<0.001)], peakVO₂ [WMD: 1.78 mL/min/kg (95% CI: 1.27–2.29 mL/min/kg, P<0.001)], HR_peak [WMD: 11.07 beats/min (95% CI: 8.04–14.11 beats/min, P<0.001)] and QoL measured by SF-36 questionnaire subscale scores. Furthermore, exercise training is well tolerated, and no major adverse event occurred related to exercise training.

Conclusions

Exercise training is associated with a significant improvement in exercise capacity, cardiorespiratory fitness and quality of life among patients with PH and proved to be safe for stable PH patients with optimization of medical therapy. However, more large-scale multicenter studies are needed to confirm the effectiveness and safety of exercise training in patients with PH.

Pulmonary hypertension: From an orphan disease to a global epidemic

[No abstract. Showing first paragraph of article]Pulmonary hypertension is a progressive disease characterized by an elevation of pulmonary artery pressure and pulmonary vascular resistance, leading to right ventricular failure and death. It remains a challenging chronic progressive disease, but the current interest and advent of medical therapy in the last 20 years has significantly changed the perception of medical community in this disease. Pulmonary hypertension is not a specific disease; the majority of cases present with other diseases and various pathological processes that affect the pulmonary vasculature, and consequently increase pulmonary pressure and vascular resistance.

Combined Methods (Formal Adjusted Indirect Comparison, Meta-Analysis and Principal Component Analysis) Comparisons of the Safety and Efficacy of Ambrisentan, Bosentan, and Sildenafil in the Patients With Pulmonary Arterial Hypertension

BACKGROUND

Three oral drugs (ambrisentan, bosentan, and sildenafil) have been widely used to treat patients with pulmonary arterial hypertension (PAH). 1) There are no studies that directly compare the safety and efficacy of these three drugs. Existing studies could not meet the physician's need to select the most beneficial drugs for patients. 2) Principal component analysis is mainly used for scale analysis and has not been reported in clinical field. 3) When the results of the indirect meta-analysis were not satisfactory, no new solutions have been proposed in existing meta-analysis studies.

METHODS

The overall process of this study is divided into 4 steps 1) literature search and data extraction; 2) principal component analysis; 3) common reference-based indirect comparison meta-analysis; 4) formal adjusted indirect comparison.

RESULTS

Nine randomized controlled trials (RCTs) experiments and eight long-term experiments were selected. The main influencing factors are mortality, 6-min walk distance (6MW), mean pulmonary arterial pressure (PAP), cardiac index (CI) by principal component analysis. There was no significant heterogeneity among the indirect meta-analysis of three drugs. But in the formal adjusted indirect comparison 1) the level of PAP of sildenafil group (60.5 ± 22.35, 220) was higher than that of the other three groups, placebo (53.5 ± 17.63, 507) (p < 0.001), ambrisentan (49.5 ± 15.08, 130) (p < 0.001), and bosentan (54.6 ± 118.41, 311) (p < 0.001); 2) the level of CI of sildenafil group (54 ± 18, 311) was higher than that of the other three groups, placebo (2.7 ± 1.09, 518) (p < 0.001), ambrisentan (2.5 ± 0.75, 130) (p < 0.001), and bosentan (2.5 ± 1.06, 333) (p < 0.001). In addition, sildenafil significantly improved the survival rate comparing with ambrisentan and bosentan.

CONCLUSIONS

The results of this study suggest that sildenafil might be more suitable for long-term treatment of PAH patients than ambrisentan and bosentan. In order to enable clinicians to draw conclusions more quickly and directly in the data-rich literature, we suggest the use of principal component analysis combined with formal adjusted indirect comparison to compare the efficacy and safety of drugs.

Diagnostic delay in pulmonary arterial hypertension: Insights from the Australian and New Zealand pulmonary hypertension registry

BACKGROUND AND OBJECTIVE

Early diagnosis of PAH is clinically challenging. Patterns of diagnostic delay in Australian and New Zealand PAH populations have not been explored in large-scale studies. We aimed to evaluate the magnitude, risk factors and survival impact of diagnostic delay in Australian and New Zealand PAH patients.

METHODS

A cohort study of PAH patients from the PHSANZ Registry diagnosed from 2004 to 2017 was performed. Diagnostic interval was the time from symptom onset to diagnostic right heart catheterization as recorded in the registry. Factors associated with diagnostic delay were analysed in a multivariate logistic regression model. Survival rates were compared across patients based on the time to diagnosis using Kaplan-Meier method and Cox regression.

RESULTS

A total of 2044 patients were included in analysis. At diagnosis, median age was 58 years (IQR: 43-69), female-to-male ratio was 2.8:1 and majority of patients were in NYHA FC III-IV (82%). Median diagnostic interval was 1.2 years (IQR: 0.6-2.7). Age, CHD-PAH, obstructive sleep apnoea and peripheral vascular disease were independently associated with diagnostic interval of ≥1 year. No improvement in diagnostic interval was seen during the study period. Longer diagnostic interval was associated with decreased 5-year survival.

CONCLUSION

PAH patients experience significant diagnostic interval, which has not improved despite increased community awareness. Age, cardiovascular and respiratory comorbidities are significantly associated with longer time to diagnosis. Mortality rates appear higher in patients who experience longer diagnostic interval.

Sex hormone exposure and reproductive factors in pulmonary arterial hypertension: a case-control study

Pulmonary arterial hypertension (PAH) is a sexually dimorphic disease that for unknown reasons affects women more than men. The role of estrogens, both endogenous and exogenous, and reproductive factors in this female susceptibility is still poorly understood. It has been strongly suggested that sex hormones may influence the development and progression of the disease. We sought to determine whether sex hormone exposures and reproductive factors associate with PAH patients compared to control subjects, using a questionnaire and interview to obtain information regarding these potential risk factors. We conducted a single-center unmatched case-control study. Six hundred and thirty-four women and men with PAH, as well as 27 subjects with BMPR2 mutations but no PAH and 132 healthy population controls were enrolled from the Vanderbilt Pulmonary Hypertension Research Cohort and researchmatch.org. Questionnaires and nurse-led interviews were conducted to obtain information regarding sex hormone exposures and reproductive factors. Additional history was obtained on enrolled patients including disease severity variables and comorbidities. Responses to the questionnaires were analyzed to describe these exposures in this population as well as assess the association between disease severity variables and sex hormone exposures. Reproductive and endogenous factors that determine lifelong estrogen exposure were similar between PAH cases and controls. Patients with associated PAH were significantly more likely to be postmenopausal compared to controls. There were similar rates of "ever-use" and duration of use of oral contraceptive pills and hormone replacement therapy in patients when compared to controls. Disease severity variables were not significantly affected by any exposure after adjusting for PAH sub-group. In contrast to our hypothesis, that a greater exposure to exogenous sources of female sex hormones associates with PAH case status, we found similar rates of endogenous and exogenous sex hormone exposure between PAH patients and unmatched controls.

Sex, Gender, and Sex Hormones in Pulmonary Hypertension and Right Ventricular Failure

Pulmonary hypertension (PH) encompasses a syndrome of diseases that are characterized by elevated pulmonary artery pressure and pulmonary vascular remodeling and that frequently lead to right ventricular (RV) failure and death. Several types of PH exhibit sexually dimorphic features in disease penetrance, presentation, and progression. Most sexually dimorphic features in PH have been described in pulmonary arterial hypertension (PAH), a devastating and progressive pulmonary vasculopathy with a 3-year survival rate <60%. While patient registries show that women are more susceptible to development of PAH, female PAH patients display better RV function and increased survival compared to their male counterparts, a phenomenon referred to as the "estrogen paradox" or "estrogen puzzle" of PAH. Recent advances in the field have demonstrated that multiple sex hormones, receptors, and metabolites play a role in the estrogen puzzle and that the effects of hormone signaling may be time and compartment specific. While the underlying physiological mechanisms are complex, unraveling the estrogen puzzle may reveal novel therapeutic strategies to treat and reverse the effects of PAH/PH. In this article, we (i) review PH classification and pathophysiology; (ii) discuss sex/gender differences observed in patients and animal models; (iii) review sex hormone synthesis and metabolism; (iv) review in detail the scientific literature of sex hormone signaling in PAH/PH, particularly estrogen-, testosterone-, progesterone-, and dehydroepiandrosterone (DHEA)-mediated effects in the pulmonary vasculature and RV; (v) discuss hormone-independent variables contributing to sexually dimorphic disease presentation; and (vi) identify knowledge gaps and pathways forward. © 2020 American Physiological Society. Compr Physiol 10:125-170, 2020.

Pulmonary arterial hypertension: the case for a bioelectronic treatment

Pulmonary arterial hypertension (PAH) is a rare disease of unknown etiology that progresses to right ventricular failure. It has a complex pathophysiology, which involves an imbalance between vasoconstrictive and vasodilative processes in the pulmonary circulation, pulmonary vasoconstriction, vascular and right ventricular remodeling, systemic inflammation, and autonomic imbalance, with a reduced parasympathetic and increased sympathetic tone. Current pharmacological treatments for PAH include several classes of drugs that target signaling pathways in vascular biology and cardiovascular physiology, but they can have severe unwanted effects and they do not typically stop the progression of the disease. Pulmonary artery denervation has been tested clinically as a method to suppress sympathetic overactivation, however it is a nonspecific and irreversible intervention. Bioelectronic medicine, in particular vagus nerve stimulation (VNS), has been used in cardiovascular disorders like arrhythmias, heart failure and arterial hypertension and could, in principle, be tested as a treatment in PAH. VNS can produce pulmonary vasodilation and renormalize right ventricular function, via activation of pulmonary and cardiac vagal fibers. It can suppress systemic inflammation, via activation of fibers that innervate the spleen. Finally, VNS can gradually restore the balance between parasympathetic and sympathetic tone by regulating autonomic reflexes. Preclinical studies support the feasibility of using VNS in PAH. However, there are challenges with such an approach, arising from the need to affect a relatively small number of relevant vagal fibers, and the potential for unwanted cardiac and noncardiac effects of VNS in this sensitive patient population.