Prevalence and outcome in systemic sclerosis associated pulmonary arterial hypertension: application of a registry approach

N-terminal pro-brain natriuretic peptide is associated with pulmonary hypertension or diastolic dysfunction in patients with systemic sclerosis: An Australian prospective cross-sectional study

Introduction

Pulmonary arterial hypertension and left ventricular diastolic dysfunction are associated with significant morbidity and mortality in systemic sclerosis. N-terminal pro-brain natriuretic peptide has been proposed as part of composite screening algorithms for pulmonary arterial hypertension. Our aim was to assess the prevalence of pulmonary hypertension and diastolic dysfunction, and evaluate their association with serum N-terminal pro-brain natriuretic peptide in systemic sclerosis patients.

Methods

Patients with systemic sclerosis were prospectively enrolled to undergo N-terminal pro-brain natriuretic peptide testing and transthoracic echocardiography at a tertiary Australian centre from January to October 2022. We collected demographic and transthoracic echocardiography variables including pulmonary hypertension estimated by tricuspid regurgitant velocity and diastolic dysfunction assessed by the ASE/EACVI 2016 guidelines. Pearson's correlation coefficient was used to evaluate association between N-terminal pro-brain natriuretic peptide and echocardiographic parameters.

Results

Sixty-one patients were enrolled (median age = 62 years (interquartile range = 55-69 years); 84% female). Two-thirds of patients had limited systemic sclerosis (40/61). Five patients (8%) had high likelihood of pulmonary hypertension by transthoracic echocardiography. Seven patients (11%) had diastolic dysfunction; however, seven patients (11%) had indeterminate diastology. Six patients underwent right heart catheterisation, with five patients diagnosed with pulmonary hypertension. N-terminal pro-brain natriuretic peptide in patients with pulmonary hypertension or diastolic dysfunction was significantly higher (median = 207 and 226 pg/mL, respectively) compared to patients without either condition (median = 69 pg/mL, p = 0.01). N-terminal pro-brain natriuretic peptide showed a statistically significant although limited correlation with estimated pulmonary pressures measured by tricuspid regurgitant velocity (r = 0.44, p = 0.002) and left ventricular filling pressures (r = 0.27, p = 0.04).

Conclusion

Pulmonary hypertension and diastolic dysfunction are both observed in systemic sclerosis. N-terminal pro-brain natriuretic peptide is associated with both conditions; however, it cannot distinguish between the two disease processes. Right heart catheterisation may be required to make this distinction.

Molecular Changes Implicate Angiogenesis and Arterial Remodeling in Systemic Sclerosis-Associated and Idiopathic Pulmonary Hypertension

BACKGROUND

Pulmonary hypertension (PH) is a common complication of systemic sclerosis (SSc) and a leading cause of mortality among patients with this disease. PH can also occur as an idiopathic condition (idiopathic pulmonary arterial hypertension). Investigation of transcriptomic alterations in vascular populations is critical to elucidating cellular mechanisms underlying pathobiology of SSc-associated and idiopathic PH.

METHODS

We analyzed single-cell RNA sequencing profiles of endothelial and perivascular mesenchymal populations from explanted lung tissue of patients with SSc-associated PH (n=16), idiopathic pulmonary arterial hypertension (n=3), and healthy controls (n=15). Findings were validated by immunofluorescence staining of explanted human lung tissue.

RESULTS

Three disease-associated endothelial populations emerged. Two angiogenic endothelial cell (EC) subtypes markedly expanded in SSc-associated PH lungs: tip ECs expressing canonical tip markers PGF and APLN and phalanx ECs expressing genes associated with vascular development, endothelial barrier integrity, and Notch signaling. Gene regulatory network analysis suggested enrichment of Smad1 (SMAD family member 1) and PPAR-γ (peroxisome proliferator-activated receptor-γ) regulon activities in these 2 populations, respectively. Mapping of potential ligand-receptor interactions highlighted Notch, apelin-APJ (apelin receptor), and angiopoietin-Tie (tyrosine kinase with immunoglobulin-like and EGF-like domains 1) signaling pathways between angiogenic ECs and perivascular cells. Transitional cells, expressing both endothelial and pericyte/smooth muscle cell markers, provided evidence for the presence of endothelial-to-mesenchymal transition. Transcriptional programs associated with arterial endothelial dysfunction implicated VEGF-A (vascular endothelial growth factor-A), TGF-β1 (transforming growth factor beta-1), angiotensin, and TNFSF12 (tumor necrosis factor ligand superfamily member 12)/TWEAK (TNF-related weak inducer of apoptosis) in the injury/remodeling phenotype of PH arterial ECs.

CONCLUSIONS

These data provide high-resolution insights into the complexity and plasticity of the pulmonary endothelium in SSc-associated PH and idiopathic pulmonary arterial hypertension and provide direct molecular insights into soluble mediators and transcription factors driving PH vasculopathy.

Role of Left Ventricular Dysfunction in Systemic Sclerosis-Related Pulmonary Hypertension

BACKGROUND

In systemic sclerosis (SSc), pulmonary hypertension remains a significant cause of morbidity and mortality. Although conventionally classified as group 1 pulmonary arterial hypertension, systemic sclerosis-related pulmonary hypertension (SSc-PH) is a heterogeneous disease. The contribution of left-sided cardiac disease in SSc-PH remains poorly understood.

RESEARCH QUESTION

How often does left ventricular (LV) dysfunction occur in SSc among patients undergoing right heart catheterization and how does coexistent LV dysfunction with SSc-PH affect all-cause mortality in this patient population?

STUDY DESIGN AND METHODS

We conducted a retrospective, observational study of 165 patients with SSc who underwent both echocardiography and right heart catheterization. LV dysfunction was identified using LV global longitudinal strain (GLS) on speckle-tracking echocardiography based on a defined threshold of > -18%. SSc-PH was defined by a mean pulmonary artery pressure > 20 mmHg.

RESULTS

Among patients with SSc who have undergone right heart catheterization, LV dysfunction occurred in 74.2% with SSc-PH and 51.2% without SSc-PH. The median survival of patients with SSc-PH and LV dysfunction was 67.9 (95% CI, 38.3-102.0) months, with a hazard ratio of 12.64 (95% CI, 1.73-92.60) for all-cause mortality when adjusted for age, sex, SSc disease duration, and FVC compared with patients with SSc without pulmonary hypertension with normal LV function.

INTERPRETATION

LV dysfunction is common in SSc-PH. Patients with SSc-PH and LV dysfunction by LV GLS have increased all-cause mortality. This suggests that LV GLS may be helpful in identifying underlying LV dysfunction and in risk assessment of patients with SSc-PH.

Survival in systemic sclerosis associated pulmonary arterial hypertension in the current treatment era-results from a nationwide study

INTRODUCTION

Pulmonary arterial hypertension (PAH) is a leading cause of mortality in systemic sclerosis (SSc). This nationwide study aims to describe real world treatment characteristics and assess survival rates of patients with SSc-PAH.

METHODS

In this retrospective cohort study, patients with SSc-PAH were identified from Turkish Ministry of Health National Electronic Database (from January 2016 to September 2022), using ICD-10 codes. Data on demographics, treatment characteristics, and death was collected. Kaplan-Meier curves were used to calculate cumulative probabilities of survival at 1, 3, and 5 years.

RESULTS

Five hundred forty-seven patients (90.7% female) with SSc-PAH were identified. Median age at PAH diagnosis was 59.9 (50.0-67.4) years. During a median follow-up duration of 3.2 (1.5-4.8) years, 199 (36.4%) deaths occurred. Estimated survival rates at 1, 3, and 5 years were 90.2%, 73.2%, and 56.6%, respectively. Survival was similar among patients with and without interstitial lung disease (p = 0.20). Patients who used immunosuppressives had better survival than those who did not (p < 0.001). No difference was observed in survival rates according to initial PAH-specific treatment regimen (monotherapy or combination) (p = 0.49).

CONCLUSION

Compared to most of historical cohorts, higher survival rates for SSc-PAH were observed in this study. Early diagnosis of PAH may have contributed to these findings. The impact of immunosuppressive therapy on prognosis of SSc-PAH needs to be further investigated in prospective studies. Key Points • Early diagnosis is pivotal for better outcomes in SSc-PAH. • Implementation of PAH treatment guidelines in routine clinical practice is still poor and should be improved. • Effect of immunosuppressive therapies on disease course has to be defined in SSc-PAH.

Performance of DETECT Pulmonary Arterial Hypertension Algorithm According to the Hemodynamic Definition of Pulmonary Arterial Hypertension in the 2022 European Society of Cardiology and the European Respiratory Society Guidelines

OBJECTIVE

The evidence-based DETECT pulmonary arterial hypertension (PAH) algorithm is frequently used in patients with systemic sclerosis (SSc) to help clinicians screen for PAH by using noninvasive data to recommend patient referral to echocardiography and, if applicable, for a diagnostic right-sided heart catheterization. However, the hemodynamic definition of PAH was recently updated in the 2022 European Society of Cardiology (ESC)/European Respiratory Society (ERS) guidelines. The performance of DETECT PAH in identifying patients with a high risk of PAH according to this new definition was assessed.

METHODS

In this post hoc analysis of DETECT, which comprised 466 patients with SSc, the performance of the DETECT PAH algorithm in identifying patients with a high risk of PAH as defined in the 2022 ESC/ERS guidelines (mean pulmonary arterial pressure [mPAP] >20 mm Hg, pulmonary capillary wedge pressure [PCWP] ≤15 mm Hg, and pulmonary vascular resistance >2 Wood units) was assessed using summary statistics and was descriptively compared to the known performance of DETECT PAH as defined in 2014, when it was developed (mPAP ≥25 mm Hg and PCWP ≤15 mm Hg).

RESULTS

The sensitivity of DETECT PAH in identifying patients with a high risk of PAH according to the 2022 ESC/ERS definition was lower (88.2%) compared to the 2014 definition (95.8%). Specificity improved from 47.8% to 50.8%.

CONCLUSION

The performance of the DETECT algorithm to screen for PAH in patients with SSc is maintained when PAH is defined according to the 2022 ESC/ERS hemodynamic definition, indicating that DETECT remains applicable to screen for PAH in patients with SSc.

Sildenafil Versus Placebo for Early Pulmonary Vascular Disease in Scleroderma (SEPVADIS): protocol for a randomized controlled trial

BACKGROUND

Pulmonary hypertension (PH) is a leading cause of death in patients with systemic sclerosis (SSc). An important component of SSc patient management is early detection and treatment of PH. Recently the threshold for the diagnosis of PH has been lowered to a mean pulmonary artery pressure (mPAP) threshold of > 20 mmHg on right heart catheterization (RHC). However, it is unknown if PH-specific therapy is beneficial in SSc patients with mildly elevated pressure (SSc-MEP, mPAP 21-24 mmHg).

METHODS

The SEPVADIS trial is a randomized, double-blind, placebo-controlled phase 2 trial of sildenafil in SSc-MEP patients with a target enrollment of 30 patients from two academic sites in the United States. The primary outcome is change in six-minute walk distance after 16 weeks of treatment. Secondary endpoints include change in pulmonary arterial compliance by RHC and right ventricular function by cardiac magnetic resonance imaging at 16 weeks. Echocardiography, serum N-terminal probrain natriuretic peptide, and health-related quality of life is being measured at 16 and 52 weeks.

DISCUSSION

The SEPVADIS trial will be the first randomized study of sildenafil in SSc-MEP patients. The results of this trial will be used to inform a phase 3 study to investigate the efficacy of treating patients with mild elevations in mPAP.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier NCT04797286.

Treatment strategies and survival of patients with connective tissue disease and pulmonary arterial hypertension: a COMPERA analysis

OBJECTIVES

Pulmonary arterial hypertension (PAH) occurs in various connective tissue diseases (CTDs). We sought to assess contemporary treatment patterns and survival of patients with various forms of CTD-PAH.

METHODS

We analysed data from COMPERA, a European pulmonary hypertension registry, to describe treatment strategies and survival in patients with newly diagnosed PAH associated with SSc, SLE, MCTD, UCTD and other types of CTD. All-cause mortality was analysed according to the underlying CTD. For patients with SSc-PAH, we also assessed survival according to initial therapy with endothelin receptor antagonists (ERAs), phosphodiesterase type 5 inhibitors (PDE5is) or a combination of these two drug classes.

RESULTS

This analysis included 607 patients with CTD-PAH. Survival estimates at 1, 3 and 5 years for SSc-PAH (n = 390) were 85%, 59% and 42%; for SLE-PAH (n = 34) they were 97%, 77% and 61%; for MCTD-PAH (n = 33) they were 97%, 70% and 59%; for UCTD-PAH (n = 60) they were 88%, 67% and 52%; and for other CTD-PAH (n = 90) they were 92%, 69% and 55%, respectively. After multivariable adjustment, the survival of patients with SSc-PAH was significantly worse compared with the other conditions (P = 0.001). In these patients, the survival estimates were significantly better with initial ERA-PDE5i combination therapy than with initial ERA or PDE5i monotherapy (P = 0.016 and P = 0.012, respectively).

CONCLUSIONS

Mortality remains high in patients with CTD-PAH, especially for patients with SSc-PAH. However, for patients with SSc-PAH, our results suggest that long-term survival may be improved with initial ERA-PDE5i combination therapy compared with initial monotherapy.

Th17/IL-17A axis is critical for pulmonary arterial hypertension (PAH) in systemic sclerosis (SSc): SSc patients with high levels of serum IL-17A exhibit reduced lung functions and increased prevalence of PAH

BACKGROUND

It is thought that systemic sclerosis (SSc) might be a T helper 17 (Th17) cell-driven autoimmune disease. Noticeably, pulmonary arterial hypertension (PAH) is a leading cause of death in patients with SSc. Here, we investigated the association between serum Th17-related cytokines and prevalence of PAH in SSc patients.

METHODS

This study included 72 SSc patients and 51 healthy controls (HC). We determined clinical manifestations, immunophenotypes including Th subsets in peripheral blood lymphocytes, and the serum levels of interleukin (IL)-17A, IL-17A/F, IL-17B. IL-17C, IL-17D. IL-1β, IL-6, IL-21, IL-22, and IL-23.

RESULTS

The frequency of Th17 cells was significantly increased in SSc patients compared to HC and was positively correlated with the modified Rodnan skin scores. Furthermore, the serum levels of IL-17A, IL-17D, IL-1β, and IL-6 were significantly increased in SSc patients compared to HC. SSc patients with detected IL-17A showed high levels of IL-17A/F, IL-1β, IL-6, and IL-22, and high frequency of Th17 cells. Interestingly, these patients exhibited the reduced lung functions and increased prevalence of PAH significantly compared to patients with undetected IL-17A. Similarly, SSc patients with detected IL-17A and high IL-6 (≥1.2 pg/mL) exhibited the decreased lung functions and increased prevalence of PAH compared to patients with undetected IL-17A and low IL-6.

CONCLUSION

We found that SSc patients with high levels of serum IL-17A or both IL-17A and IL-6 show reduced lung functions and high prevalence of PAH. Consequently, it is highly probable that Th17/IL-17A axis is critical for the prevalence of PAH in SSc patients.

Association of pulmonary hypertension with outcomes in patients with Systemic sclerosis and other connective tissue disorders: review and meta-analysis

BACKGROUND AND AIM

Pulmonary hypertension (PH) is a frequent complication of connective tissue disorders (CTDs), with a major impact on the prognosis of the disease. The aim of our study was to perform a systemic review and meta-analysis of published literature evaluating survival function in patients with systemic sclerosis (SSc) with and without PH and to compare survival function between patients with SSc, systemic lupus erythematosus (SLE), other CTDs, and conditions associated with PH.

METHODS

The established protocol of the Cochrane Collaboration Steps and meta-analysis of observational studies in epidemiology recommendations (MOOSE) were used.

RESULTS

7 studies, including 1470 SSc-PH patients and 1368 SSc patients without PH, and 4 studies, including 108 SLE-PH patients and 1288 SLE patients without PH, assessed survival function were selected. Six studies (including 777 SSc, 249 SLE, 90 idiopathic pulmonary arterial hypertension (IPAH) and 29 primary Sjogren's syndrome patients) comparing survival function in different subgroups of patients with confirmed PH were included. SSc patients with PH showed the worst survival as compared to SSc patients without PH [OR (95% CI) 3.70 (2.42-5.67); p<0.00001]. The same pattern was observed in patients with SLE. SSc patients with PH were characterized by lower survival function compared to other reasons for PH, including SLE [OR (95% CI) 2.76 (1.95-3.91); p<0.00001].

CONCLUSIONS

Patients with SSc-PH are characterized by significantly lower survival function as compared to SSc patients without PH. Among the different entities of PH, SSc shows the worst survival, underlining prognostic significance of detection and evaluation of PH according to the currently established approach.

Diagnostic value of combined FVC%/DLCO% and echocardiography in connective tissue disorder‑associated pulmonary hypertension

The main objective of the present study was to investigate whether forced vital capacity (FVC)%/diffusing capacity of the lungs for carbon monoxide (DLCO)% can be used to predict the presence of pulmonary hypertension (PH) in connective tissue disorders (CTDs). For this purpose, a total of 53 individuals who were diagnosed with CTDs and had undergone right heart catheterization between July, 2019 and July, 2022 were included in the present study. Based on the mean pulmonary artery pressure (mPAP) measured during right heart catheterization, the participants were divided into the PH and non-PH groups. The differences in demographic characteristics, including sex, age, body mass index, smoking index, FVC%/DLCO% and pulmonary artery systolic pressure (PASP) were determined by echocardiography; moreover, the 6-min walk distance, plasma brain natriuretic peptide (BNP) levels, white blood cell count, red blood cell distribution width, erythrocyte sedimentation rate and C-reactive protein levels were compared between the two groups to identify independent predictors of PH. The independent predictors were subsequently evaluated for their correlation with mPAP to assess their predictive value for PH. FVC%/DLCO%, echocardiographic PASP, and plasma BNP levels were identified as independent predictors of PH. FVC%/DLCO% and echocardiographic PASP exhibited a significant correlation with mPAP, while the correlation between plasma BNP and mPAP levels was not statistically significant. The area under the curve (AUC) value for FVC%/DLCO% alone in predicting PH was 0.791, with an optimal diagnostic threshold of 1.35, a sensitivity of 0.794 and a specificity of 0.789. The AUC for echocardiographic PASP alone in predicting PH was 0.783, with an optimal diagnostic threshold of 39.5 mmHg, a sensitivity of 0.794 and a specificity of 0.684. When combined, the AUC of the two factors in predicting PH was 0.872, with a sensitivity of 0.941 and a specificity of 0.684. Collectively, the data of the present study indicate that FVC%/DLCO% may be used as a predictive factor for CTD-PH, and its combined application with echocardiographic PASP measurement may provide additional evidence for the clinical diagnosis of CTD-PH.

10-year survival of pulmonary arterial hypertension associated with connective tissue disease: insights from a multicentre PAH registry

OBJECTIVES

To report the 10-year survival rate and prognostic factors of pulmonary arterial hypertension associated with CTD (CTD-PAH) patients, to compare treatment and survival between patients enrolled before and after 2015, and to validate the discrimination of the recommended four-strata model in predicting 10-year survival at follow-up in Chinese CTD-PAH patients.

METHODS

This study was derived from a Chinese national multicentre prospective registry study from 2009 to 2019. Medical records were collected at baseline and follow-up, including PAH-targeted therapy and binary therapy (both CTD and PAH-targeted therapy).

RESULTS

A total of 266 CTD-PAH patients were enrolled and the 10-year survival rate was 59.9% (median follow-up time: 4.85 years). Underlying CTD (SSc), baseline 6-min walking distance and SaO2 were independent risk factors for 10-year survival. The proportion of patients receiving PAH-targeted combination therapy increased from 10.1% (2009-2014) to 26.5% (2015-2019) and that of binary therapy increased from 14.8% to 35%. The 1-year survival rate increased from 89.8% (2009-2014) to 93.9%, and the 3-year survival rate increased from 80.1% (2009-2014) to 86.5% (both P > 0.05). The four-strata strategy performed well in predicting 10-year survival at follow-up (C-index = 0.742).

CONCLUSION

The 10-year survival rate of CTD-PAH patients was reported for the first time. The 10-year prognosis was poor, but there was a tendency for more standardized treatment and better survival in patients enrolled after 2015. The recommended four-strata model at follow-up can effectively predict 10-year survival in CTD-PAH patients.

Kynurenine pathway metabolism evolves with development of preclinical and scleroderma-associated pulmonary arterial hypertension

Understanding metabolic evolution underlying pulmonary arterial hypertension (PAH) development may clarify pathobiology and reveal disease-specific biomarkers. Patients with systemic sclerosis (SSc) are regularly surveilled for PAH, presenting an opportunity to examine metabolic change as disease develops in an at-risk cohort. We performed mass spectrometry-based metabolomics on longitudinal serum samples collected before and near SSc-PAH diagnosis, compared with time-matched SSc subjects without PAH, in a SSc surveillance cohort. We validated metabolic differences in a second cohort and determined metabolite-phenotype relationships. In parallel, we performed serial metabolomic and hemodynamic assessments as the disease developed in a preclinical model. For differentially expressed metabolites, we investigated corresponding gene expression in human and rodent PAH lungs. Kynurenine and its ratio to tryptophan (kyn/trp) increased over the surveillance period in patients with SSc who developed PAH. Higher kyn/trp measured two years before diagnostic right heart catheterization increased the odds of SSc-PAH diagnosis (OR 1.57, 95% CI 1.05-2.36, P = 0.028). The slope of kyn/trp rise during SSc surveillance predicted PAH development and mortality. In both clinical and experimental PAH, higher kynurenine pathway metabolites correlated with adverse pulmonary vascular and RV measurements. In human and rodent PAH lungs, expression of TDO2, which encodes tryptophan 2,3 dioxygenase (TDO), a protein that catalyzes tryptophan conversion to kynurenine, was significantly upregulated and tightly correlated with pulmonary hypertensive features. Upregulated kynurenine pathway metabolism occurs early in PAH, localizes to the lung, and may be modulated by TDO2. Kynurenine pathway metabolites may be candidate PAH biomarkers and TDO warrants exploration as a potential novel therapeutic target.NEW & NOTEWORTHY Our study shows an early increase in kynurenine pathway metabolism in at-risk subjects with systemic sclerosis who develop pulmonary arterial hypertension (PAH). We show that kynurenine pathway upregulation precedes clinical diagnosis and that this metabolic shift is associated with increased disease severity and shorter survival times. We also show that gene expression of TDO2, an enzyme that generates kynurenine from tryptophan, rises with PAH development.

Connective tissue disease-associated pulmonary hypertension: A comprehensive review

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

Pharmacological management of connective tissue disease-associated pulmonary arterial hypertension

INTRODUCTION

Pulmonary arterial hypertension (PAH) is a severe, progressive pulmonary vasculopathy (Group 1 Pulmonary Hypertension (PH)) that complicates the course of many connective tissue diseases (CTD). Detailed testing is required to differentiate PAH from other types of PH caused by CTD such as left heart disease (Group 2 PH), pulmonary parenchymal disease (Group 3 PH), and chronic thromboembolic pulmonary hypertension (Group 4 PH). PAH is most frequently seen in systemic sclerosis but can also be seen with systemic lupus erythematosus, mixed CTD, and primary Sjogren's syndrome.

AREAS COVERED

This review discusses the epidemiology of CTD-associated PAH, outlines the complex diagnosis approach, and finishes with an in-depth discussion on the current treatment paradigm. Focus is placed on challenges faced in the treatment of CTD-associated PAH, (decreased efficacy and poorer tolerance of pharmacological therapies) and includes a discussion on the future investigational treatments.

EXPERT OPINION

Despite significant advances over the past decades with more aggressive treatment algorithms, CTD-associated PAH patients continue to have poorer survival compared to those with idiopathic PAH. This review highlights factors leading to disparate outcomes compared to other forms of PAH, and discusses on further improvements that may increase quality of life and survival for CTD-associated PAH patients.

Clinical characteristics and survival of pulmonary arterial hypertension with or without interstitial lung disease in systemic sclerosis

OBJECTIVES

To describe the clinical phenotype and prognosis of people in the Australian Scleroderma (SSc) Cohort Study with pulmonary arterial hypertension (PAH) with or without interstitial lung disease (ILD).

METHODS

Participants meeting ACR/EULAR criteria for SSc were divided into four mutually exclusive groups: those meeting criteria for PAH (PAH-only), ILD (ILD-only), concurrent PAH and ILD (PAH-ILD) or neither PAH nor ILD (SSc-only). Logistic or linear regression analyses were used for associations between clinical features, health-related quality of life (HRQoL) and physical function. Survival analysis was performed using Kaplan-Meier estimates and Cox-regression modelling.

RESULTS

Of 1561 participants, 7% fulfilled criteria for PAH-only, 24% ILD-only, 7% PAH-ILD and 62% SSc-only. People with PAH-ILD were more frequently male, with diffuse skin involvement, higher inflammatory markers, older age of SSc onset and higher frequency of extensive ILD than the cohort overall (p < 0.001). People of Asian race more frequently developed PAH-ILD (p < 0.001). People with PAH-ILD or PAH-only had worse WHO functional class and 6-min-walk-distance than ILD-only (p < 0.001). HRQoL scores were worst in those with PAH-ILD (p < 0.001). Survival was reduced in the PAH-only and PAH-ILD groups (p < 0.01). Multivariable hazard modelling demonstrated the worst prognosis in extensive ILD and PAH (HR = 5.65 95% CI 3.50-9.12 p < 0.01), followed by PAH-only (HR = 4.21 95% CI 2.89-6.13 p < 0.01) and PAH with limited ILD (HR = 2.46 95% CI 1.52-3.99 p < 0.01).

CONCLUSIONS

The prevalence of concurrent PAH-ILD in the ASCS is 7%, with poorer survival in those patients with PAH-ILD compared to ILD or SSc alone. The presence of PAH confers a poorer overall prognosis than even extensive ILD; however, further data are required to better understand the clinical outcomes of this high-risk patient group.

Role of cardiopulmonary exercise test in early diagnosis of pulmonary hypertension in scleroderma patients

INTRODUCTION

Pulmonary arterial hypertension (PAH) is a severe, high mortality and progressive disease. Early diagnosis and treatment improves the prognosis. Patients with scleroderma disease presents high risk of developing PAH. Established screening strategies - echocardiogram and DETECT algorithm - recognize the disease when it is already advanced. Cardiopulmonary exercise testing (CPET) detects pulmonary vascular injury in earlier stages.

METHODS

Prospective study of 52 consecutive patients diagnosed of scleroderma in our health area, during 2 years (2018 and 2019). All of them undergo CPET, in addition to the annual systematic screening. Sensitivity of current PAH screening is compared to CPET. To confirm the presence of PAH, right heart catheterization (RHC) is performed. In case of suspected PAH in CPET, but non-confirmatory right heart catheterization at rest, patients carried out exercise RHC.

RESULTS

Fifty-two CPET were performed, of which 16 suggested PAH. Resting RHC confirmed PAH in 5 patients and exercise RHC in 7 (diagnostic sensitivity of CPET together with rest and exercise catheterization of 100%). Of these 16 patients, DETECT had identified 10, of whom resting RHC confirmed PAH in 3 and exercise RHC in 2 (guideline-based diagnostic algorithm sensitivity 70%).

CONCLUSIONS

CPET and exercise RHC could detect PAH earlier than established screening in patients with scleroderma disease, allowing early diagnosis.

Skin disorders and interstitial lung disease: Part II-The spectrum of cutaneous diseases with lung disease association

Part 2 of this 2-part CME introduces dermatologists to noninfectious inflammatory skin diseases associated with pulmonary involvement. In many cases, dermatologists may be the first physicians recognizing respiratory complications associated with these diagnoses. Because pulmonary involvement is often the leading cause of morbidity and mortality, dermatologists should be comfortable screening and monitoring for lung disease in high-risk patients, recognizing cutaneous stigmata of lung disease in these patients and referring to pulmonary specialists, when appropriate, for prompt treatment initiation. Some treatments used for skin disease may not be appropriate in the context of lung disease and hence, choosing a holistic approach is important. Interstitial lung disease and pulmonary hypertension are the most common pulmonary complications and a significant cause of mortality in autoimmune connective tissue diseases, especially systemic sclerosis, dermatomyositis, and mixed connective tissue disease. Pulmonary complications, notably interstitial lung disease, are also common and life-threatening in sarcoidosis and vasculitis, while they are variable in neutrophilic and autoimmune blistering diseases.

New Drugs and Therapies in Pulmonary Arterial Hypertension

Pulmonary arterial hypertension is a chronic, progressive disorder of the pulmonary vasculature with associated pulmonary and cardiac remodeling. PAH was a uniformly fatal disease until the late 1970s, but with the advent of targeted therapies, the life expectancy of patients with PAH has now considerably improved. Despite these advances, PAH inevitably remains a progressive disease with significant morbidity and mortality. Thus, there is still an unmet need for the development of new drugs and other interventional therapies for the treatment of PAH. One shortcoming of currently approved vasodilator therapies is that they do not target or reverse the underlying pathogenesis of the disease process itself. A large body of evidence has evolved in the past two decades clarifying the role of genetics, dysregulation of growth factors, inflammatory pathways, mitochondrial dysfunction, DNA damage, sex hormones, neurohormonal pathways, and iron deficiency in the pathogenesis of PAH. This review focuses on newer targets and drugs that modify these pathways as well as novel interventional therapies in PAH.

Serum Biomarkers in Connective Tissue Disease-Associated Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a life-threatening complication of connective tissue diseases (CTDs) characterised by increased pulmonary arterial pressure and pulmonary vascular resistance. CTD-PAH is the result of a complex interplay among endothelial dysfunction and vascular remodelling, autoimmunity and inflammatory changes, ultimately leading to right heart dysfunction and failure. Due to the non-specific nature of the early symptoms and the lack of consensus on screening strategies-except for systemic sclerosis, with a yearly transthoracic echocardiography as recommended-CTD-PAH is often diagnosed at an advanced stage, when the pulmonary vessels are irreversibly damaged. According to the current guidelines, right heart catheterisation is the gold standard for the diagnosis of PAH; however, this technique is invasive, and may not be available in non-referral centres. Hence, there is a need for non-invasive tools to improve the early diagnosis and disease monitoring of CTD-PAH. Novel serum biomarkers may be an effective solution to this issue, as their detection is non-invasive, has a low cost and is reproducible. Our review aims to describe some of the most promising circulating biomarkers of CTD-PAH, classified according to their role in the pathophysiology of the disease.

Clinical characteristics and outcomes in pulmonary manifestations of systemic sclerosis: Contribution from pulmonary hypertension and interstitial lung disease severity

Patients with systemic sclerosis complicated by both pulmonary hypertension (SSc-PH) and interstitial lung disease (SSc-PH-ILD) have poor prognosis compared to those with SSc-PH or SSc-ILD alone. Little is known of how ILD severity affects outcomes in those with SSc-PH, or how PH severity affects outcomes in those with SSc-ILD. Herein, we aimed to delineate clinical features of patients with SSc-PH and SSc-ILD and determine to what degree PH and ILD severity contribute to mortality in patients with SSc. We conducted parallel retrospective studies in cohorts of patients with SSc-PH and SSc-ILD. We categorized ILD severity by pulmonary function testing and PH severity by cardiopulmonary hemodynamics. Our primary outcome was all-cause mortality from time of PH or ILD diagnosis for the SSc-PH and SSc-ILD cohorts, respectively. We calculated adjusted risks of time to all-cause mortality using Cox proportional hazards models. In patients with SSc-PH, severe ILD (HR: 3.54; 95% CI: 1.05, 11.99) was associated with increased hazards for all-cause mortality. By contrast, mild and moderate ILD were not associated with increased mortality risk. In patients with SSc-ILD, both moderate (HR: 2.65; 95% CI: 1.12, 6.31) and severe PH (HR: 6.60; 95% CI: 2.98, 14.61) were associated with increased hazards for all-cause mortality, while mild PH was not. Through our parallel study design, the risk of all-cause mortality increases as severity of concomitant ILD or PH worsens. Therapies that target slowing disease progression earlier in the disease course may be beneficial.

Pulmonary Manifestations in Rheumatological Diseases

Pulmonary involvement complicates the various aspects of care in patients suffering from autoimmune disorders. The epidemiological data generated over the last 10 to 15 years have improved the overall understanding of the risk factors and pathophysiological mechanisms involved in pulmonary involvement in rheumatological conditions. Recent advances in genetics have provided superior insight into the pathogenesis of autoimmune diseases and the underlying pulmonary involvement. This review article provides a concise overview of the four most common rheumatological conditions associated with pulmonary involvement: systemic lupus erythematosus (SLE), dermatomyositis/polymyositis, rheumatoid arthritis (RA), and systemic sclerosis (SSc). The clinical, epidemiological, and genetic aspects of these diseases are summarized in this article with particular emphasis on the characteristic patterns of pulmonary involvement in radiological imaging and various treatment options for each of these autoimmune diseases and their lung manifestations.

The Use and Utility of Machine Learning in Achieving Precision Medicine in Systemic Sclerosis: A Narrative Review

BACKGROUND

Systemic sclerosis (SSc) is a rare connective tissue disease that can affect different organs and has extremely heterogenous presentations. This complexity makes it difficult to perform an early diagnosis and a subsequent subclassification of the disease. This hinders a personalized approach in clinical practice. In this context, machine learning (ML), a branch of artificial intelligence (AI), is able to recognize relationships in data and predict outcomes.

METHODS

Here, we performed a narrative review concerning the application of ML in SSc to define the state of art and evaluate its role in a precision medicine context.

RESULTS

Currently, ML has been used to stratify SSc patients and identify those at high risk of severe complications. Additionally, ML may be useful in the early detection of organ involvement. Furthermore, ML might have a role in target therapy approach and in predicting drug response.

CONCLUSION

Available evidence about the utility of ML in SSc is sparse but promising. Future improvements in this field could result in a big step toward precision medicine. Further research is needed to define ML application in clinical practice.

Prognostic meaning of right ventricular function and output reserve in patients with systemic sclerosis

Background

The objective of this study was to investigate the prognostic impact of right ventricular (RV) function at rest and during exercise in patients with systemic sclerosis (SSc) presenting for a screening for pulmonary hypertension (PH).

Methods

In this study, data from SSc patients who underwent routinely performed examinations for PH screening including echocardiography and right heart catheterization at rest and during exercise were analysed. Uni- and multivariable analyses were performed to identify prognostic parameters.

Results

Out of 280 SSc patients screened for PH, 225 were included in the analysis (81.3% female, mean age 58.1±13.0 years, 68% limited cutaneous SSc, WHO-FC II–III 74%, 24 manifest PH). During the observation period of 3.2±2.7 (median 2.6) years 35 patients died. Tricuspid annular plane systolic excursion (TAPSE) at rest <18 mm (p=0.001), RV output reserve as increase of cardiac index (CI) during exercise <2 l/min (p<0.0001), RV pulmonary vascular reserve (Δ mean pulmonary artery pressure/Δ cardiac output) ≥3 mmHg/l/min (p<0.0001), peak CI <5.5 l/min/m² (p=0.001), pulmonary arterial compliance <2 ml/mmHg (p=0.002), TAPSE/systolic pulmonary arterial pressure (sPAP) ratio ≤0.6 ml/mmHg (p<0.0001) and echocardiographic qualitative RV function at rest (p<0.0001) significantly predicted worse survival. In the multivariable analysis TAPSE/sPAP ratio and diffusion capacity for carbon monoxide ≤65% were identified as independent prognostic predictors and had 75% sensitivity and 69% specificity to predict future development of pulmonary vascular disease (PVD) during follow-up.

Conclusions

This study demonstrates that assessment of RV function at rest and during exercise may provide crucial information to identify SSc patients who are at a high risk of poor outcome and for the development of PH and/or PVD.

Sex Differences in Pulmonary Hypertension

Pulmonary hypertension (PH) includes multiple diseases that share as common characteristic an elevated pulmonary artery pressure and right ventricular involvement. Sex differences are observed in practically all causes of PH. The most studied type is pulmonary arterial hypertension (PAH) which presents a gender bias regarding its prevalence, prognosis, and response to treatment. Although this disease is more frequent in women, once affected they present a better prognosis compared to men. Even if estrogens seem to be the key to understand these differences, animal models have shown contradictory results leading to the birth of the estrogen paradox. In this review we will summarize the evidence regarding sex differences in experimental animal models and, very specially, in patients suffering from PAH or PH from other etiologies.

Systemic sclerosis in Asians: Are there racial differences?

Systemic sclerosis is a multisystemic autoimmune disease characterized by vasculopathy and fibrosis. Racial factors exert a significant influence on the epidemiology, clinical manifestations, antibody profile, mortality and genetic factors in systemic sclerosis. In this review, we examined Asian systemic sclerosis cohorts reported in Asia and multi-racial cohort studies to evaluate the disease characteristics and outcomes of systemic sclerosis in Asians. Asian patients have distinct genetic susceptibility to systemic sclerosis, younger age of systemic sclerosis onset, higher frequency of diffuse skin involvement, different autoantibody profiles such as higher frequency of anti-Scl70 and anti-U1-RNP antibodies, and more severe clinical phenotype. There was a suggestion of poorer survival among Asians that may be contributed by more severe disease, socioeconomic factors and differences in healthcare systems. Recognizing the influence of racial differences in systemic sclerosis disease course is important as it has implications for appropriate treatment, monitoring and prognostication.

Diagnosis and Treatment of Pulmonary Arterial Hypertension: A Review

IMPORTANCE

Pulmonary arterial hypertension (PAH) is a subtype of pulmonary hypertension (PH), characterized by pulmonary arterial remodeling. The prevalence of PAH is approximately 10.6 cases per 1 million adults in the US. Untreated, PAH progresses to right heart failure and death.

OBSERVATIONS

Pulmonary hypertension is defined by a mean pulmonary artery pressure greater than 20 mm Hg and is classified into 5 clinical groups based on etiology, pathophysiology, and treatment. Pulmonary arterial hypertension is 1 of the 5 groups of PH and is hemodynamically defined by right heart catheterization demonstrating a mean pulmonary artery pressure greater than 20 mm Hg, a pulmonary artery wedge pressure of 15 mm Hg or lower, and a pulmonary vascular resistance of 3 Wood units or greater. Pulmonary arterial hypertension is further divided into subgroups based on underlying etiology, consisting of idiopathic PAH, heritable PAH, drug- and toxin-associated PAH, pulmonary veno-occlusive disease, PAH in long-term responders to calcium channel blockers, and persistent PH of the newborn, as well as PAH associated with other medical conditions including connective tissue disease, HIV, and congenital heart disease. Early presenting symptoms are nonspecific and typically consist of dyspnea on exertion and fatigue. Currently approved therapy for PAH consists of drugs that enhance the nitric oxide-cyclic guanosine monophosphate biological pathway (sildenafil, tadalafil, or riociguat), prostacyclin pathway agonists (epoprostenol or treprostinil), and endothelin pathway antagonists (bosentan and ambrisentan). With these PAH-specific therapies, 5-year survival has improved from 34% in 1991 to more than 60% in 2015. Current treatment consists of combination drug therapy that targets more than 1 biological pathway, such as the nitric oxide-cyclic guanosine monophosphate and endothelin pathways (eg, ambrisentan and tadalafil), and has shown demonstrable improvement in morbidity and mortality compared with the previous conventional single-pathway targeted monotherapy.

CONCLUSIONS AND RELEVANCE

Pulmonary arterial hypertension affects an estimated 10.6 per 1 million adults in the US and, without treatment, typically progresses to right heart failure and death. First-line therapy with drug combinations that target multiple biological pathways are associated with improved survival.

Increased risk of mortality in systemic sclerosis-associated pulmonary hypertension: a systemic review and meta-analysis

BACKGROUND

Pulmonary hypertension (PH) is a frequent complication of systemic sclerosis (SSc) and is currently one of the primary causes of death in patients with this disease. We conducted a systematic review and meta-analysis to assess the association between PH and mortality in patients with SSc to verify trends in mortality in patients with SSc-associated PH.

METHODS

We searched the PubMed and Embase databases for published studies on SSc-associated PH from inception to May 2021. All cohort studies in which mortality and/or survival for SSc-associated PH were reported were included in the analysis. The outcome parameters were pooled and analyzed using a random-effects model via generic inverse-variance weighting in conventional and cumulative meta-analysis.

RESULTS

The literature search identified 1161 citations, and the full texts of 54 studies were examined. Sixteen articles, with a total of 7857 patients with SSc and 1140 patients with SSc-associated PH, were included in the meta-analysis. Patients with SSc-associated PH had a higher pooled risk of mortality than patients with SSc without PH (risk ratio = 3.12; 95% confidence interval: [2.44, 3.98]).

CONCLUSIONS

This meta-analysis revealed a higher mortality in patients with SSc-associated PH. PH was a significant predictor of death in patients with SSc. Thus, early diagnosis and treatment of PH are important in patients with SSc.

Impact of interstitial lung disease on the survival of systemic sclerosis with pulmonary arterial hypertension

To assess severity markers and outcomes of patients with systemic sclerosis (SSc) with or without pulmonary arterial hypertension (PAH-SSc/non-PAH-SSc), and the impact of interstitial lung disease (ILD) on PAH-SSc. Non-PAH-SSc patients from the Spanish SSc registry and PAH-SSc patients from the Spanish PAH registry were included. A total of 364 PAH-SSc and 1589 non-PAH-SSc patients were included. PAH-SSc patients had worse NYHA-functional class (NYHA-FC), worse forced vital capacity (FVC) (81.2 ± 20.6% vs 93.6 ± 20.6%, P < 0.001), worse tricuspid annular plane systolic excursion (TAPSE) (17.4 ± 5.2 mm vs 19.9 ± 6.7 mm, P < 0.001), higher incidence of pericardial effusion (30% vs 5.2%, P < 0.001) and similar prevalence of ILD (41.8% vs. 44.9%). In individuals with PAH-SSc, ILD was associated with worse hemodynamics and pulmonary function tests (PFT). Up-front combination therapy was used in 59.8% and 61.7% of patients with and without ILD, respectively. Five-year transplant-free survival rate was 41.1% in PAH-SSc patients and 93.9% in non-PAH-SSc patients (P < 0.001). Global survival of PAH-SSc patients was not affected by ILD regardless its severity. The multivariate survival analysis in PAH-SSc patients confirmed age at diagnosis, worse NYHA-FC, increased PVR, reduced DLCO, and lower management with up-front combination therapy as major risk factors. In conclusion, in PAH-SSc cohort risk of death was greatly increased by clinical, PFT, and hemodynamic factors, whereas it was decreased by up-front combination therapy. Concomitant ILD worsened hemodynamics and PFT in PAH-SSc but not survival regardless of FVC impairment.

sPAP/PAAT Ratio as a New Index of Pulmonary Vascular Load: A Study in Normal Subjects and Ssc Patients with and without PH

In pulmonary hypertension (PH), the development of right ventricular (RV) dilatation and RV failure are signs of accelerated progression of the disease, resulting in an increased risk of cardiac death. Even the noninvasive assessment of systolic blood pressure in the pulmonary artery undertaken by echocardiography does not provide a measure of ventricle–pulmonary interaction. Some studies have shown the potential for echocardiography to indirectly evaluate pulmonary vascular resistance (PVR) and the acceleration time of pulmonary outflow (PAAT). We used systolic pulmonary artery pressure (sPAP) and pulmonary vascular resistance to develop an sPAP/PAAT ratio (strength/surface unit)/(time) for this study. From January 2017 to December 2018, 60 healthy subjects and 63 patients with systemic scleroderma (Ssc) (60 females, 3 males), 27 with PH and 36 without PH at two-dimensional echocardiographic/Doppler, were screened. In normal subjects, the mean sPAP/PAAT ratio was 0.26 ± 0.063, which indicated optimal pulmonary arterial ventricle coupling and biventricular function. The data derived from the analysis of the Ssc patients showed that those presenting pre-capillary PH at cardiac catheterization had an sPAP/PAAT ratio of 0.40 ± 0.05. There was a significant correlation between sPAP/PAAT with Walk Distance (WD) and PVR, but not with TAPSE. Interobserver variability was less than 5%. The sPAP/PAAT ratio is a new parameter that may indicate pulmonary vascular afterload and interaction, both in normal subjects and in patients with Ssc and PH.

High prevalence of occult left ventricular diastolic dysfunction detected by exercise stress test in systemic sclerosis

Despite the poor prognosis of systemic sclerosis (SSc) due to the co-occurrence of left ventricular diastolic dysfunction (LVDD), presence of occult LVDD has not been sufficiently investigated. This retrospective study aimed to reveal the prevalence and determinants of occult LVDD in patients with SSc by exercise stress test. Forty-five SSc patients (age, 63 ± 13 years; men/women, 6/39) with normal pulmonary artery pressure and pulmonary artery wedge pressure (PAWP) at rest underwent a symptom-limited exercise test with right heart catheterization using a supine cycle ergometer; haemodynamic parameters at rest, leg raise and during exercise were evaluated. Occult LVDD defined PAWP ≥ 25 mmHg during exercise was seen in 13 patients (29%). Higher PAWP, lower pulmonary vascular resistance and diastolic pulmonary pressure gradient, larger left atrium at rest, and higher PAWP during leg raise (15 ± 4 vs 10 ± 4 mmHg in non-LVDD group, p < 0.001) were observed in the occult LVDD group. The area under the ROC curve for PAWP after leg raise was largest at 0.83 (95% CI: 0.70–0.95, p = 0.001). About one-third (29%) of SSc patients with normal haemodynamics at rest showed occult LVDD. A higher PAWP after leg raise could be useful for detecting occult LVDD.

Clinical phenotypes, hemodynamic characteristics and prognosis of Chinese patients with systemic sclerosis-associated precapillary pulmonary hypertension: a retrospective study

INTRODUCTION

Systemic sclerosis (SSc) is associated with interstitial lung disease (ILD) and pulmonary arterial hypertension (PAH). This study aimed to explore the prevalence, clinical features, hemodynamic characteristics and prognosis of different severity of ILD in a cohort of patients with SSc-associated precapillary pulmonary hypertension (SSc-PH) and investigate the differences between SSc-PAH and idiopathic pulmonary arterial hypertension (IPAH) patients.

METHOD

SSc-PH patients and IPAH patients, admitted to Shanghai Pulmonary Hospital (August 1, 2008-January 31, 2020) and diagnosed by right-sided heart catheterization (RHC) or echocardiography, were retrospectively included. SSc-PH patients had a baseline chest high-resolution computed tomography (HRCT), and PH classification was based on the extent of ILD. Clinical, pulmonary function, hemodynamic characteristics and survival data were extracted.

RESULTS

The study included 45 SSc-PH patients (60% had coexisting ILD and 77.8% were SSc-Group 1 PH/SSc-PAH [without ILD or with mild ILD], 22.2% were SSc-Group 3 PH/SSc-PH with severe ILD) and 52 IPAH patients. SSc-PH with ILD had lower arterial oxygen partial pressure (PaO₂) than those without ILD. Hemodynamic characteristics and survival rates were comparable between SSc-PAH with mild ILD and those without ILD. SSc-Group 3 PH had lower pulmonary vascular resistance (PVR) and more severe restrictive ventilatory dysfunction than SSc-Group 1 PH, but the survival rate was equally poor. SSc-PAH had a poorer prognosis than IPAH patients despite the better hemodynamic characteristics.

CONCLUSIONS

ILD was common in SSc-PH patients. Careful phenotyping of PH in SSc-PH patients is very important as it is imperative to recognize its impact on clinical course, treatment and survival.

KEY POINTS

• ILD was common in Chinese SSc-PH patients. • SSc-PH patients with ILD had lower PaO₂ than those without ILD. • Hemodynamic characteristics and survival rates were similar in SSc-PAH patients with mild ILD and those without ILD. • Patients in SSc-Group 3 PH had lower pulmonary vascular resistance (PVR) and more severe restrictive ventilatory dysfunction than those in SSc-Group 1 PH, but the survival rate was equally poor. SSc-PAH patients had a poorer prognosis than IPAH patients despite their better hemodynamic characteristics.

Heart Involvement in Systemic Sclerosis: the Role of Magnetic Resonance Imaging

Systemic sclerosis (SSc) is a severe connective tissue disease characterized by diffuse vascular damage and aberrant activation of immune system, resulting in inflammation and fibrosis of skin and internal organs, including the heart. Cardiac involvement is frequent in SSc, even though often unrecognized due to the occult nature at early stages and to the lack of a defined diagnostic algorithm. Once clinically evident, heart involvement is associated with a poor prognosis, representing the leading cause of death in about one third of SSc patients. Thus, its early recognition and monitoring are of crucial importance to allow a prompt therapeutic intervention and to improve patients' outcomes. Cardiac Magnetic Resonance (CMR) is a non-invasive, non-radiating imaging technique of great importance for the assessment of cardiovascular system, and represents the modality of choice for the morpho-functional and structural characterization of the heart. In SSc, CMR allows a precise definition of biventricular and biatrial size and function, and a detailed tissue characterization. CMR has been therefore extensively proposed in SSc as a non-invasive diagnostic tool to characterize heart involvement, particularly myocardial involvement. In this review, we summarize the most recent evidences to support the use of CMR in SSc as an important tool to recognize and characterize scleroderma heart disease. Furthermore, the unmet needs and the future perspectives of a CMR-based approach for the early detection of SSc heart involvement are discussed.

Systemic Sclerosis: From Pathophysiology to Novel Therapeutic Approaches

Systemic sclerosis (SSc) is a systemic, immune-mediated chronic disorder characterized by small vessel alterations and progressive fibrosis of the skin and internal organs. The combination of a predisposing genetic background and triggering factors that causes a persistent activation of immune system at microvascular and tissue level is thought to be the pathogenetic driver of SSc. Endothelial alterations with subsequent myofibroblast activation, excessive extracellular matrix (ECM) deposition, and unrestrained tissue fibrosis are the pathogenetic steps responsible for the clinical manifestations of this disease, which can be highly heterogeneous according to the different entity of each pathogenic step in individual subjects. Although substantial progress has been made in the management of SSc in recent years, disease-modifying therapies are still lacking. Several molecular pathways involved in SSc pathogenesis are currently under evaluation as possible therapeutic targets in clinical trials. These include drugs targeting fibrotic and metabolic pathways (e.g., TGF-β, autotaxin/LPA, melanocortin, and mTOR), as well as molecules and cells involved in the persistent activation of the immune system (e.g., IL4/IL13, IL23, JAK/STAT, B cells, and plasma cells). In this review, we provide an overview of the most promising therapeutic targets that could improve the future clinical management of SSc.

Cytokine signatures differentiate systemic sclerosis patients at high versus low risk for pulmonary arterial hypertension

BACKGROUND

Pulmonary arterial hypertension (PAH) affects approximately 10% of patients with systemic sclerosis (SSc) and is a leading cause of death. We sought to identify serum cytokine signatures that risk stratify SSc patients for this potentially fatal complication.

METHODS

Subjects at high risk for PAH and with incident PAH based on right heart catheterization (RHC) were enrolled in the multi-center prospective registry, Pulmonary Hypertension Assessment and Recognition of Outcomes in Scleroderma (PHAROS). Low-risk SSc patients were enrolled at Stanford and had normal pulmonary function test and echocardiogram parameters. Serum was available from 71 high-risk patients, 81 incident PAH patients, 10 low-risk patients, and 20 healthy controls (HC). Custom 14- and 65-plex arrays were used for cytokine analysis. Cytokine expression was compared between patient groups by principal component analysis and Tukey's test result. A multiple hypotheses corrected p value <0.05 was considered significant.

RESULTS

Exploratory analysis using principal components showed unique clustering for each patient group. There was a significant difference in cytokine expression in at least one group comparison for every cytokine. Overall, there was very little difference in cytokine expression comparing high-risk and PAH patient groups; however, these groups had substantially different cytokine profiles compared to low-risk patients and HC.

CONCLUSION

These data suggest that cytokine profiles can distinguish SSc patients who are at high-risk for or have PAH from SSc patients who may be at lower risk for PAH and HC. However, high-risk and PAH patients had very similar cytokine profiles, suggesting that these patients are on a disease continuum.

Estimates of Prevalence of Pulmonary Hypertension according to Different International Definitions

Background

Pulmonary hypertension is a dreaded disease associated with considerable morbidity and mortality. The pulmonary hypertension developing due to chronic respiratory disease is a unique subset with symptoms often getting masqueraded by the underlying respiratory condition. The importance of early detection of this complication has been realized worldwide, and recently, the definition of pulmonary hypertension was revised to set the cutoff of mean pulmonary artery pressure (mPAP) at 20 mmHg instead of 25 mmHg at rest. In our study, we have tried to estimate the difference this new definition brings to the prevalence of pulmonary hypertension among interstitial lung disease patients at our centre.

Methods

This was a cross-sectional study in which all the patients of ILDs (n = 239) attending the outdoor and indoor Department of Respiratory Medicine, King George's Medical University, India, for the duration of one year were subjected to transthoracic echocardiography along with measurement of serum pro-B-type natriuretic peptide (BNP) and troponin T values. The data were analyzed using the different definitions, and the prevalence was compared.

Result

Incidence of pulmonary hypertension among ILD patients at mPAP cutoff ≥ 25 was 28.9%, while that at value ≥20 mmHg, incidence of pulmonary hypertension increased to 46.0%. An increment of 15-20% in incidence of pulmonary hypertension was observed among different types of ILD when cutoff of mPAP was changed.

Conclusion

The new definition helps in a significant increase in the detection of pulmonary hypertension, which certainly helps in earlier detection and better management of patients.

The role of TGF-β or BMPR2 signaling pathway-related miRNA in pulmonary arterial hypertension and systemic sclerosis

Pulmonary arterial hypertension (PAH) is a severe complication of connective tissue disease (CTD), causing death in systemic sclerosis (SSc). The past decade has yielded many scientific insights into microRNA (miRNAs) in PAH and SSc. This growth of knowledge has well-illustrated the complexity of microRNA (miRNA)-based regulation of gene expression in PAH. However, few miRNA-related SSc-PAH were elucidated. This review firstly discusses the role of transforming growth factor-beta (TGF-β) signaling and bone morphogenetic protein receptor type II (BMPR2) in PAH and SSc. Secondly, the miRNAs relating to TGF-β and BMPR2 signaling pathways in PAH and SSc or merely PAH were subsequently summarized. Finally, future studies might develop early diagnostic biomarkers and target-oriented therapeutic strategies for SSc-PAH and PAH treatment.

Improvement with time of vascular outcomes in systemic sclerosis: a systematic review and meta-analysis study

OBJECTIVES

Vascular disease in systemic sclerosis (SSc) is associated with significant morbidity and mortality. Preliminary data may lead to the suggestion of a modifiable unified-vascular endophenotype. Our aim was to determine whether the prevalence, mortality, and severity of SSc-vascular disease have changed over time.

METHODS

We performed a systematic review and meta-analysis of the literature in PubMed 1950-2019 related to SSc-digital ulcers (DUs), pulmonary artery hypertension (PAH) and scleroderma renal crisis (SRC). We included full-text articles and extracted study characteristics and assessed risk of bias/quality. We examined the prevalence, mortality, and surrogate measures of SSc-associated vascular disease severity.

RESULTS

We included 55 studies in our meta-analysis. The pooled prevalence of DUs (41.0%), PAH (9.5%) and SRC (4.9%) remained largely stable over time. There was significant improvement in PAH 1-year (p= 0.001) and SRC mortality (P = <0.001), but not PAH 3-year (p= 0.312) or 5-year (p= 0.686) mortality. The prevalence of DU healing did not significantly change (p= 0.265). There was a trend (all P=∼0.1) towards improvement in PAH surrogates: mean pulmonary artery pressure, pulmonary vascular resistance, and right atrial pressure. For SRC, there was evidence that the overall frequency of dialysis (66.7%, p= 0.297) and permanent dialysis (34.5%, p= 0.036) increased over time.

CONCLUSION

Despite the heterogeneity and scarcity of the disease, there have been major improvements obtained in the various vascular complications in SSc leading to benefit in survival. This is supported by a trend towards improvement in several surrogate markers and demonstrates that progresses in vascular management translate into major patient benefit.

Evaluation and Comparison of Quantitative Right Ventricular Strain Assessment by Cardiac Magnetic Resonance in Pulmonary Hypertension Using Feature Tracking and Deformable Registration Algorithms

RATIONALE AND OBJECTIVE

Deformable registration algorithms (DRA) has been used to detect left ventricular myocardial changes, however, its clinical utility in right ventricular (RV) function has not been evaluated. In this study, we aim to evaluate and compare quantitative RV strain assessment by cardiac magnetic resonance in pulmonary hypertension (PH) using feature tracking (FT) and DRA.

MATERIALS AND METHODS

Thirty patients were confirmed to have PH using right heart catheterization, and 16 healthy controls were evaluated with cardiac magnetic resonance. Global and segmental RV strain was measured by DRA and FT methods. Intraclass correlation coefficients (ICCs), coefficient of variation, and Bland-Altman analysis were used to assess and compare the interobserver and intraobserver variability of the DRA and FT methods.

RESULTS

DRA was more sensitive than FT in the detection of RV circumferential and septal dysfunction. The global longitudinal strain (GLS) obtained by the two methods was reduced in mild-moderate PH patients (mean pulmonary artery pressure≤45 mm Hg), and the GLS and global circumferential strain (GCS) were reduced in severe PH patients (mean pulmonary artery pressure >45 mm Hg). DRA and FT methods demonstrate similar observer agreement in global strain using ICC (ICC greater than 0.90), but RV strain derived from DRA had lower variability using COV ([8%-14%] for DRA versus [11%-39%] for FT).For segmental longitudinal strain, DRA showed higher ICC and lower COV compared with that of the FT method. Correlations between RVEF and RV global strain parameters were strong (p < 0.01):GLS-DRA, r = -0.696; GLS-FT, r = -0.832; GCS-DRA, r = -0.745; and GCS-FT, r = -0.817. GLS-DRA was weakly correlated with mPAP (r = 0.385, p < 0.05).In multiple linear regression analysis, RVEF and mPAP were independent predictors of GLS-DRA (R² = 0.57, p < 0.01).

CONCLUSIONS

The DRA method is more sensitive and robust for RV myocardial strain measurements than FT method.

Advances in the management of pulmonary arterial hypertension

The management of pulmonary arterial hypertension (PAH) has significantly evolved over the last decades in the wake of more sensitive diagnostics and specialized clinical programs that can provide focused medical care. In the current era of PAH care, 1-year survival rates have increased to 86%–90% from 65% in the 1980s, and average long-term survival has increased to 6 years from 2.8 years. The heterogeneity in the etiology and disease course has opened doors to focusing research in phenotyping the disease and understanding the pathophysiology at a cellular and genetic level. This may eventually lead to precision medicine and the development of medications that may prevent or reverse pulmonary vascular remodeling. With more insight, clinical trial designs and primary end-points may change to identify the true survival benefit of pharmacotherapy. Identifying responders from non-responders to therapy may help provide individualized patient-centered care rather than an algorithm-based approach. The purpose of this review is to highlight the latest advances in screening, diagnosis, and management of PAH.

Overexpression of Msx1 in Mouse Lung Leads to Loss of Pulmonary Vessels Following Vascular Hypoxic Injury

Pulmonary arterial hypertension (PAH) is a progressive lung disease caused by thickening of the pulmonary arterial wall and luminal obliteration of the small peripheral arteries leading to increase in vascular resistance which elevates pulmonary artery pressure that eventually causes right heart failure and death. We have previously shown that transcription factor Msx1 (mainly expressed during embryogenesis) is strongly upregulated in transformed lymphocytes obtained from PAH patients, especially IPAH. Under pathological conditions, Msx1 overexpression can cause cell dedifferentiation or cell apoptosis. We hypothesized that Msx1 overexpression contributes to loss of small pulmonary vessels in PAH. In IPAH lung, MSX1 protein localization was strikingly increased in muscularized remodeled pulmonary vessels, whereas it was undetectable in control pulmonary arteries. We developed a transgenic mouse model overexpressing MSX1 (MSX1^OE) by about 4-fold and exposed these mice to normoxic, sugen hypoxic (3 weeks) or hyperoxic (100% 02 for 3 weeks) conditions. Under normoxic conditions, compared to controls, MSX1^OE mice demonstrated a 30-fold and 2-fold increase in lung Msx1 mRNA and protein expression, respectively. There was a significant retinal capillary dropout (p < 0.01) in MSX1^OE mice, which was increased further (p < 0.03) with sugen hypoxia. At baseline, the number of pulmonary vessels in MSX1^OE mice was similar to controls. In sugen-hypoxia-treated MSX1^OE mice, the number of small (0-25 uM) and medium (25-50 uM) size muscularized vessels increased approximately 2-fold (p < 0.01) compared to baseline controls; however, they were strikingly lower (p < 0.001) in number than in sugen-hypoxia-treated control mice. In MSX1^OE mouse lung, 104 genes were upregulated and 67 genes were downregulated compared to controls. Similarly, in PVECs, 156 genes were upregulated and 320 genes were downregulated from siRNA to MSX1^OE, and in PVSMCs, 65 genes were upregulated and 321 genes were downregulated from siRNA to MSX1^OE (with control in the middle). Many of the statistically significant GO groups associated with MSX1 expression in lung, PVECs, and PVSMCs were similar, and were involved in cell cycle, cytoskeletal and macromolecule organization, and programmed cell death. Overexpression of MSX1 suppresses many cell-cycle-related genes in PVSMCs but induces them in PVECs. In conclusion, overexpression of Msx1 leads to loss of pulmonary vessels, which is exacerbated by sugen hypoxia, and functional consequences of Msx1 overexpression are cell-dependent.

[Characteristics of patients with connective tissue disease-associated pulmonary arterial hypertension treated with prostanoids: A multicenter retrospective study]

INTRODUCTION

Pulmonary arterial hypertension (PAH) is a severe complication of connective tissue disease (CTD). Data on use of prostanoids in this particular subset of patients are lacking. We aimed to describe the characteristics of patients with PAH-CTD treated with prostanoids and the outcomes under treatment.

METHODS

In this multicenter retrospective study, all patients treated with prostanoids since 2006 were included. Data on PAH and CTD were collected at the time of prostanoid introduction and under treatment.

RESULTS

Twenty-one patients were included, of whom 20 (95%) had limited cutaneous systemic sclerosis. Nineteen patients were treated with oral monotherapy or combination before addition of prostanoid. Treprostinil was the most used molecule (57% of patients). At the time of prostanoid introduction, 90% of patients were considered at high risk for death. Among patients who had right heart catheterization during follow-up, there was no significant difference in haemodynamics. No extrarespiratory worsening of the CTD was reported. The 1-year survival under prostanoid was 62%. In univariate analysis, NYHA functional class was associated with survival under treatment.

CONCLUSION

This study provides original data on use of prostanoids in a cohort consisting mainly of systemic sclerosis. It underlines the difficulty to achieve a standardized assessment in this subset of patients. Safety profile was comparable with data reported in idiopathic PAH.

Identifying early pulmonary arterial hypertension biomarkers in systemic sclerosis: machine learning on proteomics from the DETECT cohort

Pulmonary arterial hypertension (PAH) is a devastating complication of systemic sclerosis (SSc). Screening for PAH in SSc has increased detection, allowed early treatment for PAH and improved patient outcomes. Blood-based biomarkers that reliably identify SSc patients at risk of PAH, or with early disease, would significantly improve screening, potentially leading to improved survival, and provide novel mechanistic insights into early disease. The main objective of this study was to identify a proteomic biomarker signature that could discriminate SSc patients with and without PAH using a machine learning approach and to validate the findings in an external cohort.

Serum samples from patients with SSc and PAH (n=77) and SSc without pulmonary hypertension (non-PH) (n=80) were randomly selected from the clinical DETECT study and underwent proteomic screening using the Myriad RBM Discovery platform consisting of 313 proteins. Samples from an independent validation SSc cohort (PAH n=22 and non-PH n=22) were obtained from the University of Sheffield (Sheffield, UK).

Random forest analysis identified a novel panel of eight proteins, comprising collagen IV, endostatin, insulin-like growth factor binding protein (IGFBP)-2, IGFBP-7, matrix metallopeptidase-2, neuropilin-1, N-terminal pro-brain natriuretic peptide and RAGE (receptor for advanced glycation end products), that discriminated PAH from non-PH in SSc patients in the DETECT Discovery Cohort (average area under the receiver operating characteristic curve 0.741, 65.1% sensitivity/69.0% specificity), which was reproduced in the Sheffield Confirmatory Cohort (81.1% accuracy, 77.3% sensitivity/86.5% specificity).

This novel eight-protein biomarker panel has the potential to improve early detection of PAH in SSc patients and may provide novel insights into the pathogenesis of PAH in the context of SSc.

Early screening for pulmonary arterial hypertension in patients with systemic sclerosis improves patient outcome. This study identified a novel eight-protein biomarker panel that has the potential to assist early detection of PAH in this patient group.https://bit.ly/373BNkL

Systemic Sclerosis-Associated Pulmonary Hypertension: Spectrum and Impact

Systemic sclerosis-associated pulmonary arterial hypertension (SSc-PAH) is a catastrophic complication of one of the most common and devastating autoimmune diseases. Once diagnosed, it becomes the leading cause of mortality among this patient population. Screening modalities and risk assessments have been designed and validated by various organizations and societies in order to identify patients early in their disease course and promptly refer them to expert centers for a hemodynamic assessment and formal diagnosis. Moreover, several large multicenter clinical trials have now included patients with SSc-PAH to assess their response to therapy. Despite an improved understanding of the condition and significant advances in supportive and targeted therapy, outcomes have remained far from optimal. Therefore, rigorous phenotyping and search for novel therapies are desperately needed for this devastating condition.

Connective Tissue Disease-Associated Pulmonary Arterial Hypertension in Southern Taiwan: A Single-Center 10-Year Longitudinal Observation Cohort

Background: Pulmonary arterial hypertension (PAH) is a life-threatening disease with different etiologies and outcomes. We aimed to explore differences in clinical features and outcomes of idiopathic PAH (iPAH) and connective tissue disease-related PAH (CTD-PAH) in Taiwanese patients and determine risk factors for mortality. Methods: We retrospectively reviewed the medical records of patients with right-sided heart catheterization-diagnosed PAH between January 2005 and December 2015. The iPAH (n = 31) and CTD-PAH (n = 14) patients were enrolled and followed until December 31, 2019. Between-group comparisons were conducted. Potential predictors of the mortality of PAH were determined using the Cox proportional hazard regression model. Results: CTD-PAH patients had higher levels of N-terminal pro-brain natriuretic peptide (NT-proBNP) and lower predicted diffusing capacity of carbon monoxide (DLCO) than iPAH patients. The mortality rates were similar between CTD-PAH and iPAH (21.4% vs. 22.6%, p = 0.99). A mean pulmonary arterial pressure (mPAP) > 46 mmHg was a predictor of PAH-induced mortality (adjusted hazard ratio 21.8, 95% confidence interval 2.32–204.8). Conclusions: A higher mPAP level, but not underlying CTDs, imposed a significantly increased risk of mortality to patients with PAH.

Cardiopulmonary Exercise Testing Is an Accurate Tool for the Diagnosis of Pulmonary Arterial Hypertension in Scleroderma Related Diseases

The early diagnosis of pulmonary arterial hypertension (PAH) is a major determinant of prognosis in patients affected by connective tissue diseases (CTDs) complicated by PAH. In the present paper we investigated the diagnostic accuracy of cardiopulmonary exercise testing (CPET) in this specific setting. We recorded clinical and laboratory data of 131 patients who underwent a CPET at a pulmonary hypertension clinic. Out of them, 112 (85.5%) had a diagnosis of CTDs; 8 (6.1%) received a diagnosis of CTDs-PAH and 11 (8.4%) were affected PH of different etiology. Among CPET parameters the following parameters showed the best diagnostic performance for PAH: peak volume of oxygen uptake (VO₂; AUC: 0.845, CI95% 0.767-0.904), ratio between ventilation and volume of exhaled carbon dioxide (VE/VCO₂ slope; AUC: 0.888, CI95%: 0.817-0.938) and end-tidal partial pressures (PetCO₂; AUC: 0.792, CI95%: 0.709-0.861). These parameters were comparable among CTDs-PAH and PH of different etiology. The diagnostic performance was even improved by creating a composite score which included all the three parameters identified. In conclusion, CPET is a very promising tool for the stratification of risk of PAH among CTDs patients; the use of composite measures may improve diagnostic performance.

Nailfold Capillaroscopy in Systemic Sclerosis Patients with and without Pulmonary Arterial Hypertension: A Systematic Review and Meta-Analysis

Systemic sclerosis (SSc)-related pulmonary arterial hypertension (SSc-PAH) is a leading cause of mortality in SSc. The extent of peripheral microvasculopathy assessed through nailfold capillaroscopy might correlate with the presence of PAH in SSc patients. We searched the PubMed, Cochrane Library, Scopus, and Web of Science databases and performed a random effects meta-analysis of observational studies comparing nailfold capillaroscopic alterations in SSc-PAH versus SSc-noPAH patients. Weighted mean differences (WMD) with the corresponding confidence intervals (CIs) were estimated. The quality of the included studies was evaluated using a modified Newcastle-Ottawa scale. Seven studies with 101 SSc-PAH and 277 SSc-noPAH participants were included. Capillary density was marginally reduced in the SSc-PAH group (WMD: -1.0, 95% CI: -2.0 to 0.0, I² = 86%). This effect was strengthened once PAH diagnosis was confirmed by right heart catheterization (WMD: -1.2, 95% CI: -2.3 to -0.1, I² = 85%). An increase in capillary loop width was observed in SSc-PAH compared to SSc-noPAH patients (WMD: 10.9, 95% CI: 2.5 to 19.4, I² = 78%). Furthermore, SSc-PAH patients had a 7.3 times higher likelihood of active or late scleroderma pattern (95% CI: 3.0 to 18.0, I² = 4%). SSc-PAH patients presented with worse nailfold capillaroscopic findings compared to SSc-noPAH patients.

Pulmonary hypertension in connective tissue diseases, new evidence and challenges

Pulmonary arterial hypertension is a lethal complication of different connective tissue diseases such as systemic sclerosis, mixed connective tissue disease and systemic lupus erythematosus. Although the treatment possibilities for patients with pulmonary arterial hypertension have increased in the last two decades and survival of patients with idiopathic pulmonary arterial hypertension has improved, the latter is not the case for patients with pulmonary arterial hypertension associated with connective tissue disease. In this narrative review, we review recent literature and describe the improvement of early diagnostic possibilities, screening modalities and treatment options. We also point out the pitfalls in diagnosis in this patient category and describe the unmet needs and what the focus of future research should be.