Early detection of pulmonary arterial hypertension

Wearable Hyperspectral Photoplethysmography Allows Continuous Monitoring of Exercise-Induced Hypertension

Continuous blood pressure (BP) monitoring is essential for cardiovascular health, yet current BP sensors face cuff-dependent limitations. Cuff-free alternatives still suffer from discomfort and discontinuous measurement. Here a wearable hyperspectral photoplethysmography (HS-PPG) is reported for continuous and nonconscious BP monitoring. The HS-PPG module integrates an ultrathin and high-resolution double-folded solid immersion grating microspectrometer (DFSIG-µSPEC) with a white light LED. DFSIG-µSPEC shows an average spectral resolution of 3.4 nm for 550-800 nm in the operational range. The HS-PPG module has a compact physical dimension of 8 mm × 16 mm × 24 mm, suitable for wrist-wearable configuration. The PPG waveforms contain 50 spectral bands, achieving precise measurement of arteriolar pulse transit time (aPTT). The diastolic and systolic BPs are precisely estimated with R-values of 0.92 and 0.96, and mean absolute differences (MAD) of 1.20 and 0.40 mmHg with the 2-element Windkessel model, respectively. Further, the BP is continuously measured with heart rate (HR) and respiratory exchange ratio (RER) with exercise-induced hypertension. Continuous monitoring of systolic blood pressure (SBP) exhibits immediate responses during hemodynamic changes, with the physiological parameters of SBP, HR, and RER during exercise and recovery. The wearable HS-PPG clearly supports the strong potential for high-fidelity continuous BP monitoring.

Right ventricular outflow tract fractional shortening: a novel diagnostic parameter for pulmonary hypertension

Pulmonary hypertension (PH) is a progressive vascular disease characterized by elevated pulmonary arterial pressure and resistance in the pulmonary vascular bed. It is associated with high morbidity and mortality. Although right heart catheterization (RHC) is the gold standard for diagnosis, noninvasive methods, such as echocardiography, are essential for early detection and management. This study aimed to elucidate the potential of right ventricular outflow tract fractional shortening (RVOT-FS) as a noninvasive diagnostic tool for PH. This single-center observational cohort study was conducted between November 2023 and May 2024. The study included 141 patients referred to the PH clinic (75 with confirmed PH and 66 controls). Echocardiographic measurements were performed using standard protocols, and RVOT-FS was calculated. Hemodynamic parameters were obtained via RHC. RVOT-FS was significantly lower in the PH group (35.71%, IQR: 27.15-43.33) than in the control group (54.50%, IQR: 45.21-69.17) (p < 0.001). RVOT-FS showed negative correlations with mean pulmonary artery pressure (mPAP) (r = - 0.664, p < 0.001), pulmonary vascular resistance (PVR) (r = - 0.526, p < 0.001), and other RHC and RV echocardiographic parameters. ROC analysis demonstrated that RVOT-FS is a reliable parameter for predicting PH, with an area under the curve (AUC) of 0.866. An RVOT-FS value of 44.05% had a sensitivity of 82.7% and specificity of 83.3% for diagnosing PH. This study revealed that RVOT-FS was significantly lower in the PH group than in the control group. The correlations also observed between RVOT-FS and mPAP, PVR, and other RHC and echocardiographic parameters imply its potential clinical utility.

Pulmonary hypertension post-liver transplant: A case report

BACKGROUND

Liver transplantation (LTx) is vital in patients with end-stage liver disease, with metabolic dysfunction-associated steatotic liver disease being the most common indication. Primary sclerosing cholangitis (PSC) is an important indication. Portopulmonary hypertension, associated with portal hypertension, poses a significant perioperative risk, making pretransplant screening essential.

CASE SUMMARY

We report the case of a 41-year-old woman with PSC who developed severe pulmonary hypertension years after a successful LTx. She presented with worsening dyspnea on exertion and presyncope. Diagnostic evaluation confirmed severe precapillary pulmonary hypertension without evidence of recurrent portal hypertension. Initial management with Sildenafil and Macitentan led to a significant improvement in her symptoms, exercise capacity, and biomarkers. This case highlights the rare development of de novo pulmonary hypertension in a liver transplant recipient without recurrent portal hypertension, possibly linked to autoimmune processes or primary liver disease itself. The patient's positive response to the combination therapy underscores the importance of prompt diagnosis and aggressive management.

CONCLUSION

In conclusion, pulmonary arterial hypertension post-LTx is a rare but serious complication with a poor prognosis, necessitating further research to better understand its mechanisms and to develop effective strategies for prevention and treatment.

Predictors, prevalence and prognostic role of pulmonary hypertension in patients with chronic kidney disease: a systematic review and meta-analysis

BACKGROUND

To estimate the predictors, prevalence and prognostic role of pulmonary hypertension (PH) in patients with chronic kidney disease (CKD) using meta-analysis.

METHODS

The PubMed, EmBase, and the Cochrane library were systematically searched for eligible studies from inception till May 2024. All of pooled analyses were performed using the random-effects model.

RESULTS

Fifty observational studies involving 17,558 CKD patients were selected. The prevalence of PH in CKD patients was 38% (95% confidence interval [CI]: 33%-43%), and the prevalence according to CKD status were 31% (95% CI: 20%-42%) for CKD (I-V), 39% (95% CI: 25%-54%) for end stage kidney disease (ESKD) (predialysis), 42% (95% CI: 35%-50%) for ESKD (hemodialysis), and 26% (95% CI: 19%-34%) for renal transplant. We noted the risk factors for PH in CKD included Black individuals (relative risk [RR]: 1.39; 95% CI: 1.18-1.63; p < 0.001), chronic obstructive pulmonary disease (RR: 1.48; 95% CI: 1.21-1.82; p < 0.001), cardiovascular disease history (RR: 1.62; 95% CI: 1.05-2.51; p = 0.030), longer dialysis (RR: 1.70; 95% CI: 1.18-2.46; p = 0.005), diastolic dysfunction (RR: 1.88; 95% CI: 1.38-2.55; p < 0.001), systolic dysfunction (RR: 3.75; 95% CI: 2.88-4.87; p < 0.001), and grade 5 CKD (RR: 5.64; 95% CI: 3.18-9.98; p < 0.001). Moreover, PH in CKD patients is also associated with poor prognosis, including all-cause mortality, major cardiovascular events, and cardiac death.

CONCLUSION

This study systematically identified risk factors for PH in CKD patients, and PH were associated with poor prognosis. Therefore, patients with high prevalence of PH should be identified for treatment.

Role of Exercise Hemodynamics in the Prediction of Pulmonary Arterial Hypertension in BMPR2 Mutation Carriers

BACKGROUND

Exercise hemodynamics are recommended for early detection of pulmonary arterial hypertension (PAH) and have been suggested to be predictive of future development of PAH in high-risk populations such as BMPR2 mutation carriers. However, the optimal exercise hemodynamic screening parameter remains to be determined. Recent data suggest that pulmonary vascular distensibility (α) may serve as a useful parameter for early detection of PAH.

RESEARCH QUESTION

What is the value of exercise hemodynamics, including α, for predicting the occurrence of PAH during long-term follow-up in BMPR2 mutation carriers?

STUDY DESIGN AND METHODS

Fifty-two asymptomatic BMPR2 mutation carriers who underwent symptom-limited exercise hemodynamic assessment were followed up for a median of 10 years. The impact of hemodynamics at rest and exercise, presence of exercise pulmonary hypertension, and α on occurrence of PAH during long-term follow-up were assessed.

RESULTS

During long-term follow-up, five patients developed PAH. Patients who developed PAH showed a significantly lower α (0.8 ± 0.4%/mm Hg) than patients without PAH (1.8 ± 0.8%/mm Hg; P = .008). The only hemodynamic parameter that predicted the occurrence of PAH during long-term follow-up at regression analysis was α. Receiver operating characteristic analysis showed that α ≤ 1.5%/mm Hg predicted PAH occurrence with a specificity of 75% and sensitivity of 100%.

INTERPRETATION

The results of this study indicate that before development of PAH in BMPR2 mutation carriers, α is reduced markedly and may serve as a useful parameter in the setting of early disease detection. Given the low event rate, caution is warranted in interpreting these results, highlighting the need for validation studies.

Evidence and unresolved questions in pulmonary hypertension: Insights from the 5th French Pulmonary Hypertension Network Meeting

Pulmonary hypertension (PH) continues to present significant challenges to the medical community, both in terms of diagnosis and treatment. The advent of the updated 2022 European Society of Cardiology (ESC) and European Respiratory Society (ERS) guidelines has introduced pivotal changes that reflect the rapidly advancing understanding of this complex disease. These changes include a revised definition of PH, updates to the classification system, and treatment algorithm. While these guidelines offer a critical framework for the management of PH, they have also sparked new discussions and questions. The 5th French Pulmonary Hypertension Network Meeting (Le Kremlin-Bicêtre, France, 2023), addressed these emergent questions and fostering a deeper understanding of the disease's multifaceted nature. These discussions were not limited to theoretical advancements but extended into the practical realms of patient management, highlighting the challenges and opportunities in applying the latest guidelines to clinical practice.

Analysis of terminated pulmonary hypertension clinical trials. What are we doing wrong?

Despite significant interest in the diagnosis and treatment of pulmonary hypertension (PH) over the past two decades, there have been no notable advancements in reducing mortality. One contributing factor to this lack of progress is the insufficient number of well-designed and conducted trials. We aimed to evaluate factors associated with termination of PH clinical trials, to serve as a reference when designing future trials. We searched the ClinicalTrials.gov database for PH clinical trials conducted between January 1st 2000 to December 31st 2020. Information collected and analyzed included trial design, status, and publication status. Of the 240 analyzed clinical trials, 81% evaluated therapeutic interventions. Around 30.4% of the trials were terminated, most commonly due to recruitment issues. Terminated trials had a significantly lower number of enrolled patients when compared to trials that were completed (p= .017). Furthermore, there was an overall negative correlation between the year of trial initiation and the total number of enrolled patients (r= -0.18; p= .013). The likelihood of termination decreased by 1.9% for every additional enrolled patient. Ultimately, only 37.5% of the trials have been published. There was a significant positive correlation between number of patients enrolled and the journal's impact factor (r = 0.4, p < 0.05). Pharmaceutical companies sponsored the majority of the trials. The termination rate of PH trials is higher than other conditions. Factors such as recruitment contribute significantly to termination. Further studies are required to evaluate the challenges associated with recruiting this patient population.

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

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

Exploring Diagnostic and Therapeutic Odyssey in Pulmonary Arterial Hypertension: Insights from In-Depth Semi-Structured Interviews

INTRODUCTION

Establishing a diagnosis is paramount in medical practice as it shapes patients' experiences and guides treatment. Patients grappling with rare diseases face a triple challenge: prolonged diagnostic journeys, limited responses to existing therapies, and the absence of effective monitoring tools. Genetic diagnosis often provides crucial diagnostic and prognostic information, opening up possibilities for genotype-targeted treatments and facilitating counselling and relative testing. The NIHR BioResource - Rare Diseases (NBR) Study and the Cohort Study in Idiopathic and Hereditary Pulmonary Arterial Hypertension (PAH Cohort study) aimed to enhance diagnosis and treatment for PAH, successfully identifying the genetic cause in 25% of idiopathic cases. However, the diagnostic and therapeutic odyssey in patients with PAH remains largely unexplored.

METHODS

Stakeholders from the NBR and PAH Cohort studies were recruited using purposive sampling. In-depth interviews and focus groups were recorded, transcribed, anonymised, and analysed thematically using MAXQDA software.

RESULTS

The study involved 53 interviews and focus groups with 63 participants, revealing key themes across five stages of the diagnostic odyssey: initial health concerns and interactions with general practitioners, experiences of misdiagnosis, relief upon receiving the correct diagnosis, and mixed emotions regarding genetic results and the challenges of living with the disease. Following the diagnosis, participants embarked on a therapeutic journey, facing various challenges, including the disease's impact on professional and social lives, the learning curve associated with understanding the disease, shifts in communication dynamics with healthcare providers, therapeutic hurdles, and insurance-related issues. Building on these insights, we identified areas of unmet needs, such as improved collaboration with primary care providers and local hospitals, the provision of psychological support and counselling, and the necessity for ongoing patient education in the ever-evolving realms of research and therapy.

CONCLUSIONS

The study highlights the significant challenges encountered throughout the diagnostic and therapeutic journey in PAH. To enhance patient outcomes, it is crucial to raise awareness of the disease, establish clear diagnostic pathways, and seamlessly integrate genetic diagnostics into clinical practice. Streamlining the diagnostic process can be achieved by utilising existing clinical infrastructure to support research and fostering better communication within the NHS. Moreover, there is an urgent need for more effective therapies alongside less burdensome drug delivery methods.

The latest definition and classification of pulmonary hypertension

Pulmonary hypertension (PH) is a serious potential complication of some congenital heart diseases (CHDs). PH encompasses a range of diseases which may be idiopathic or inherited, or secondary to cardiac, respiratory, systemic or thromboembolic conditions, amongst others. Our increasing understanding of the normal ranges of pulmonary haemodynamics, as well as evidence supporting the benefits of early treatment, has resulted in a number of recent revisions to the haemodynamic definition of PH. In this Review Article, we report on the recent updates to haemodynamic definitions and classification of PH, as reflected in the 2022 Pulmonary Hypertension Guidelines and particularly focus on the CHD related sub-type of PH, where the aetiology is often multi-factorial.

Exercise-Induced Pulmonary Hypertension in Long-Term Survivors of Congenital Diaphragmatic Hernia

OBJECTIVE

To determine the prevalence of exercise-induced pulmonary hypertension (PH) among long-survivors of congenital diaphragmatic hernia repair.

STUDY DESIGN

This is a single-center, retrospective cohort study of CDH survivors who underwent exercise stress echocardiography (ESE) at Boston Children's Hospital from January 2006 to June 2020. PH severity was assessed by echocardiogram at baseline and after exercise. Patients were categorized by right ventricular systolic pressure (RVSP) after exercise: Group 1 - no or mild PH; and Group 2 - moderate or severe PH (RVSP ≥ 60 mmHg or ≥ ½ systemic blood pressure).

RESULTS

Eighty-four patients with CDH underwent 173 ESE with median age 8.1 (4.8 - 19.1) years at first ESE. Sixty-four patients were classified as Group 1, 11 as Group 2, and 9 had indeterminate RVSP with ESE. Moderate to severe PH after exercise was found in 8 (10%) patients with no or mild PH at rest. Exercise-induced PH was associated with larger CDH defect size, patch repair, use of ECMO, supplemental oxygen at discharge, and higher WHO functional class. Higher VE/VCO2 slope, lower peak oxygen saturation, and lower percent predicted FEV1, and FEV1/FVC ratio were associated with Group 2 classification. ESE changed management in 9/11 Group 2 patients. PH was confirmed in all 5 Group 2 patients undergoing cardiac catheterization after ESE.

CONCLUSIONS

Among long-term CDH survivors, 10% had moderate-severe exercise-induced PH on ESE, indicating ongoing pulmonary vascular abnormalities. Further studies are needed to optimally define PH screening and treatment for patients with repaired CDH.

Early detection of pulmonary arterial hypertension through [18F] positron emission tomography imaging with a vascular endothelial receptor small molecule

The objective of this study is to provide a positron emission tomography (PET) imaging modality targeting vascular endothelial growth factor receptors (VEGFR) for the early noninvasive detection and assessment of pulmonary arterial hypertension (PAH) severity. To validate the effectiveness of the [18F]VEGFR PET tracer, we utilized a monocrotaline (MCT)-induced PAH rat model. Molecular optical imaging, using a Cy5.5-conjugated VEGFR targeting agent, was employed to demonstrate the uptake of the agent at pulmonary arterioles, correlating with the onset and progression of PAH. Histological examinations of the MCT-PAH rat lung revealed a significant correlation between VEGFR2 expression and the pathogenesis of PAH. Molecular optical imaging demonstrated heightened uptake of the Cy5.5-conjugated VEGFR targeting agent at pulmonary arterioles, corresponding with the onset and progression of PAH. [18F]VEGFR PET showed increased lung uptake detectable in early-stage PAH before increase in pulmonary artery pressures, and this uptake correlated with increased PAH severity. Moreover, when compared to [18F]FDG PET, [18F]VEGFR PET exhibited markedly lower background cardiac signal, enhancing imaging sensitivity for lung abnormalities. Our study provides a compelling evidence for the potential utility of the innovative [18F]VEGFR PET tracer, in non-invasively detecting early signs of PAH, and monitoring its progression. The observed correlations between VEGFR2 expression, molecular optical imaging results, and [18F]VEGFR PET findings support the use of this tracer for early detection, and assessment of PAH severity. The lower background cardiac signal observed with [18F]VEGFR PET further enhances its imaging sensitivity, emphasizing its potential clinical significance.

Associations of Digital Ulcers in Patients with Systemic Sclerosis: An 8-Year Retrospective Study

INTRODUCTION

This study aimed to investigate the associations of digital ulcers (DUs) in patients with systemic sclerosis (SSc).

METHODS

This retrospective study investigated the demographic characteristics, specific autoantibodies, organ involvement, and laboratory tests in patients with SSc from our hospital.

RESULTS

This study enrolled 144 patients with SSc. The DU+ group consisted of 15 (10.4%) patients. Patients with SSc having DUs have longer disease duration, higher fibrinogen, higher fibrin degradation product, and lower cholesterol. None of the patients used cholesterol-lowering drugs before onset of DUs. The study also demonstrated a higher prevalence of anti-dsDNA and anti-histone antibodies in patients with SSc with DUs. Anti-dsDNA antibody is a specific antibody for SLE with a specificity of 96-99%. A total of 86.1% (124/144) of patients suffered from diffuse cutaneous SSc, and 28.5% (41/144) of patients suffered from overlap syndrome.

CONCLUSION

Our study indicated that patients with SSc with fibrinogen of >2.895 g/L (p = 0.043) and cholesterol of <3.340 mmol/L (p = 0.036), which is equal to 129.258 mg/dL, are at high risk of developing DUs.

International trends in pulmonary hypertension mortality between 2001 and 2019: Retrospective analysis of the WHO mortality database

BACKGROUND

There are limited published data on mortality trends in pulmonary hypertension (PH) worldwide. The objective of this study was to assess the PH-related mortality and time trends in the general population over the past 20 years.

MATERIAL AND METHODS

We used country-level PH mortality data from the World Health Organization (WHO) mortality database (2000-19), using the International Classification of Diseases, tenth revision (ICD-10) codes (I27.0, I27.2, I27.8, or I27.9). The average annual percentage changes (AAPCs) were calculated to describe mortality trends.

RESULTS

Fifty-four countries were included in this study. Between 2017 and 2019, the average age-standardized death rates (per 100,000) were 0.80 and 0.87 for males and females, respectively. Joinpoint analyses revealed a decreasing PH mortality trend for the overall population from 2000 to 2019 (AAPC -3.2 [95% confidence interval (CI) -4.1 to -2.4]), which was consistent between males and females (males: AAPC -5.3 [95% CI -6.2 to -4.4], females: AAPC -1.7 [95% CI -2.4 to -0.9]). When the estimates were stratified by etiology, we found that the mortality rates from idiopathic pulmonary arterial hypertension (I27.0) and pulmonary heart disease (unspecified, I27.9) had decreased significantly, while the mortality rates in other secondary PH (I27.2) and other specified pulmonary heart diseases (I27.8) had significantly increased. In addition, there were substantial differences in mortality rates and time trends across countries.

CONCLUSION

Although an overall decrease in PH mortality trends over the past two decades, there were substantial differences across countries. For countries with high or rising mortality rates, more efforts are needed to reduce the mortality.

A topological data analysis study on murine pulmonary arterial trees with pulmonary hypertension

Pulmonary hypertension (PH), defined by a mean pulmonary arterial blood pressure above 20 mmHg in the main pulmonary artery, is a cardiovascular disease impacting the pulmonary vasculature. PH is accompanied by chronic vascular remodeling, wherein vessels become stiffer, large vessels dilate, and smaller vessels constrict. Some types of PH, including hypoxia-induced PH (HPH), also lead to microvascular rarefaction. This study analyzes the change in pulmonary arterial morphometry in the presence of HPH using novel methods from topological data analysis (TDA). We employ persistent homology to quantify arterial morphometry for control and HPH mice characterizing normalized arterial trees extracted from micro-computed tomography (micro-CT) images. We normalize generated trees using three pruning algorithms before comparing the topology of control and HPH trees. This proof-of-concept study shows that the pruning method affects the spatial tree statistics and complexity. We find that HPH trees are stiffer than control trees but have more branches and a higher depth. Relative directional complexities are lower in HPH animals in the right, ventral, and posterior directions. For the radius pruned trees, this difference is more significant at lower perfusion pressures enabling analysis of remodeling of larger vessels. At higher pressures, the arterial networks include more distal vessels. Results show that the right, ventral, and posterior relative directional complexities increase in HPH trees, indicating the remodeling of distal vessels in these directions. Strahler order pruning enables us to generate trees of comparable size, and results, at all pressure, show that HPH trees have lower complexity than the control trees. Our analysis is based on data from 6 animals (3 control and 3 HPH mice), and even though our analysis is performed in a small dataset, this study provides a framework and proof-of-concept for analyzing properties of biological trees using tools from Topological Data Analysis (TDA). Findings derived from this study bring us a step closer to extracting relevant information for quantifying remodeling in HPH.

Development and Validation of a Nomogram for Predicting All-Cause Mortality in Patients with Hemodialysis Having Pulmonary Hypertension

INTRODUCTION

Patients with end-stage renal disease receiving hemodialysis (HD) have a high morbidity and mortality rate associated with pulmonary hypertension (PH). A nomogram was developed to predict all-cause mortality in HD patients with PH. In this study, we aimed to validate the usefulness of this nomogram.

METHODS

A total of 274 HD patients with PH were hospitalized at the Affiliated Hospital of Xuzhou Medical University between January 2014 and June 2019 and followed up for 3 years. Echocardiography detected PH when the peak tricuspid regurgitation velocity (TRV) was more than 2.8 m/s. To evaluate the all-cause mortality for long-term HD patients with PH, Cox regression analysis was performed to determine the factors of mortality that were included in the prediction model. Next, the area under the receiver-operating characteristic curve (AUC-ROC) was used to assess the predictive power of the model. Calibration plots and decision curve analysis (DCA) were used to assess the accuracy of the prediction results and the clinical utility of the model.

RESULTS

The all-cause mortality rate was 29.20% throughout the follow-up period. The nomogram comprised six commonly available predictors: age, diabetes mellitus, cardiovascular disease, hemoglobin, left ventricular ejection fraction, and TRV. The 1-year, 2-year, and 3-year AUC-ROC values were 0.842, 0.800, and 0.781, respectively. The calibration curves revealed excellent agreement with the nomogram, while the DCA demonstrated favorable clinical practicability.

CONCLUSION

The first developed nomogram for predicting all-cause mortality in HD patients with PH could guide clinical decision-making and intervention planning.

The Current Role of Cardiopulmonary Exercise Test in the Diagnosis and Management of Pulmonary Hypertension

Pulmonary arterial hypertension (PAH) is a progressive disease with a poor prognosis if left untreated. Despite remarkable achievements in understanding disease pathophysiology, specific treatments, and therapeutic strategies, we are still far from a definitive cure for the disease, and numerous evidences have underlined the importance of early diagnosis and treatment to improve the prognosis. Cardiopulmonary exercise testing (CPET) is the gold standard for assessing functional capacity and evaluating the pathophysiological mechanisms underlying exercise limitation. As effort dyspnea is the earliest and one of the main clinical manifestations of PAH, CPET has been shown to provide valid support in early detection, differential diagnosis, and prognostic stratification of PAH patients, being a useful tool in both the first approach to patients and follow-up. The purpose of this review is to present the current applications of CPET in pulmonary hypertension and to propose possible future utilization to be further investigated.

The cascade screening in heritable forms of pulmonary arterial hypertension

Heritable pulmonary artery hypertension (HPAH) is an increasingly recognized type of pulmonary arterial hypertension, in both pediatric and adult population. Intrinsic to hereditary disease, screening for genetic mutations within families is an important component of diagnosis and understanding burden of disease. Recently, consensus guidelines are published for genetic screening in PAH. These guidelines include recommendations for screening at diagnosis, noting individuals with presumed PAH due to familial, or idiopathic etiologies. Cascade genetic testing is specifically recommended as a testing paradigm to screen relatives for detection of mutation carriers, who may be asymptomatic. Without targeted genetic testing, familial mutation carriers may only come to attention when pulmonary vascular disease burden is high enough to cause symptoms, suggesting more advanced disease. Here, we present our collective experience with HPAH in five distinct families, specifically to report on the clinical courses of patients who were diagnosed with genetic mutation at diagnosis versus those who were offered genetic screening. In three families, asymptomatic mutation carriers were identified and monitored for clinical worsening. In two families, screening was not done and affected family members presented with advanced disease.

Pharmacotherapy for Pulmonary Hypertension in Infants with Bronchopulmonary Dysplasia: Past, Present, and Future

Approximately 8-42% of premature infants with chronic lung disease of prematurity, bronchopulmonary dysplasia (BPD), develop pulmonary hypertension (PH). Infants with BPD-PH carry alarmingly high mortality rates of up to 47%. Effective PH-targeted pharmacotherapies are desperately needed for these infants. Although many PH-targeted pharmacotherapies are commonly used to treat BPD-PH, all current use is off-label. Moreover, all current recommendations for the use of any PH-targeted therapy in infants with BPD-PH are based on expert opinion and consensus statements. Randomized Control Trials (RCTs) are needed to determine the efficacy of PH-targeted treatments in premature infants with or at risk of BPD-PH. Prior to performing efficacy RCTs, studies need to be conducted to obtain pharmacokinetic, pharmacodynamic, and safety data for any pharmacotherapy used in this understudied and fragile patient population. This review will discuss current and needed treatment strategies, identify knowledge deficits, and delineate both challenges to be overcome and approaches to be taken to develop effective PH-targeted pharmacotherapies that will improve outcomes for premature infants with or at risk of developing BPD-PH.

Combination of echocardiography and pulmonary function tests could predict no complication of pulmonary hypertension during 5 years in patients with systemic sclerosis

OBJECTIVE

To determine whether complications of pulmonary hypertension (PH) can be predicted by noninvasive screening tests in systemic sclerosis (SSc).

METHODS

Forty-seven of 113 SSc patients underwent right heart catheterization (RHC) during 2011-2014. Clinical data, hemodynamic features, echocardiography, and pulmonary function tests had been followed up from the first RHC until 5 years later.

RESULTS

At the first RHC, out of 44 patients, 8 were diagnosed with pre-capillary PH (mean pulmonary arterial pressure [mPAP] > 20 mm Hg), and 36 patients were defined as no-PH (mPAP ≤ 20 mm Hg). Three patients with >15 mm Hg of pulmonary artery wedge pressure were excluded. Receiver operating characteristic analyses for pre-capillary PH using estimated systolic PAP (esPAP) revealed an area under the curve (AUC) of 0.736, with a sensitivity and specificity of 62.5% and 86.1%, respectively, at a cutoff level of 35.0 mm Hg. The predicted percentage diffusing lung capacity for carbon monoxide (DLCO%) revealed an AUC of 0.840, with a sensitivity and specificity of 85.7% and 80.0%, respectively, at a cutoff level of 70.0%. Six pre-capillary PH patients, including one who died from PH 14 months after the first RHC, indicated exacerbations of mPAP or esPAP within 5 years. When esPAP < 35.0 mm Hg and DLCO% > 70% were met as the cutoff, none had been newly diagnosed with PH over 5 years.

CONCLUSIONS

The conventional screening tests may be useful for detecting pre-capillary PH with SSc, and both esPAP < 35.0 mm Hg and DLCO% > 70% indicated a lower risk of developing PH for at least 5 years.

Dynamic Prediction of Pulmonary Hypertension in Systemic Sclerosis Using Landmark Analysis

OBJECTIVE

Pulmonary hypertension (PH) is a serious complication of systemic sclerosis (SSc). In this study, we explored the prediction of short-term risk for PH using serial pulmonary function tests (PFTs) and other disease features.

METHODS

SSc patients in whom disease onset occurred ≥10 years prior to data retrieval and for whom autoantibody specificity and PFT data were available were included in this study. Mixed-effects modeling was used to describe changes in PFTs over time. Landmarking was utilized to include serial assessments and stratified Cox proportional hazards regression analysis with landmarks as strata was used to develop the PH prediction models.

RESULTS

We analyzed data from 1,247 SSc patients, 16.3% of whom were male and 35.8% of whom had diffuse cutaneous SSc. Anticentromere, antitopoisomerase, and anti-RNA polymerase antibodies were observed in 29.8%, 22.0%, and 11.4% of patients, respectively, and PH developed in 13.6% of patients. Over time, diffusing capacity for carbon monoxide (DLco) and carbon monoxide transfer coefficient (Kco) declined in all SSc patients (up to 1.5% per year) but demonstrated much greater annual decline (up to 4.5% and 4.8%, respectively) in the 5-7 years preceding PH diagnosis. Comparisons between multivariable models including either DLco, Kco, or forced vital capacity (FVC)/DLco ratio, demonstrated that both absolute values and change over the preceding year in those measurements were strongly associated with the risk of PH (hazard ratio [HR] 0.93 and 0.76 for Kco and its change; HR 0.90 and 0.96 for DLco and its change; and HR 1.08 and 2.01 for FVC/DLco ratio and its change; P < 0.001 for all). The Kco-based model had the greatest discriminating ability (Harrell's C-statistic 0.903).

CONCLUSION

Our findings strongly support the importance of PFT trends over time in identifying patients at risk of developing PH.

Krüppel-like Factor 7 inhibits proliferation and migration of pulmonary smooth muscle cells via p21 activation

The aberrant proliferation and migration of pulmonary arterial smooth muscle cells (PASMCs) are critical contributors to the pulmonary vascular remodeling that occurs during the development of Pulmonary arterial hypertension (PAH). Krüppel-like Factor 7 (KLF7) has been reported to be involved in the development of certain cardiovascular diseases. However, the role of KLF7 in PAH remains unknown. Here, we aimed to explore whether KLF7 mediates the proliferation and migration of PASMCs and its underlying mechanism. In this study, Sprague Dawley rats were exposed to 60 mg/kg monocrotaline (MCT) for 3 weeks to induce PAH and human PASMCs were stimulated with 20 ng/ml platelet-derived growth factor-BB (PDGF-BB) for 24 h to induce proliferation and migration. The mRNA and protein expression of KLF7 were significantly down-regulated in MCT-induced PAH rats and PDGF-BB-treated PASMCs. Under normal conditions, KLF7 knockdown obviously promoted PASMCs proliferation and migration, whereas KLF7 overexpression exhibited the opposite effects. Furthermore, PDGF-BB promoted the PASMCs proliferation and migration, increased the cell proportion in S phase, which was significantly attenuated by overexpression of KLF7. Mechanistic investigation indicated that KLF7 through activation its target protein, the cell cycle inhibitor p21, which finally leading to the inhibition of PASMCs growth. Consistently, UC2288, a specific inhibitor of p21, partially reversed the PASMCs proliferation inhibited by KLF7 overexpression. Taken collectively, the data suggested that KLF7 inhibits PASMCs proliferation and migration via p21 pathway and it may be used as a new therapeutic target for the PAH.

Alterations of pulmonary vascular afterload in exercise-induced pre- and post-capillary pulmonary hypertension

Exercise imposes increased pulmonary vascular afterload based on rises in pulmonary artery (PA) wedge pressure, declines in PA compliance, and resistance-compliance time. In health, afterload stress stabilizes during steady-state exercise. Our objective was to examine alterations of these exercise-associated stresses in states of pre- and post-capillary pulmonary hypertension (PH). PA hemodynamics were evaluated at rest, 2 and 7 min of steady-state exercise at moderate intensity in patients who exhibited Pre-capillary (n = 22) and post-capillary PH (n = 22). Patients with normal exercise hemodynamics (NOR-HD) (n = 32) were also studied. During exercise in all groups, PA wedge pressure increased at 2 min, with no further change at 7 min. In post-capillary PH and NOR-HD, increases in PA diastolic pressure and diastolic pressure gradient remained stable at 2 and 7 min of exercise, while in pre-capillary PH, both continued to increase at 7 min. The behavior of the diastolic pressure gradient was linearly related to the duration of resistance-compliance time at rest (r²  = 0.843) and exercise (r²  = 0.760). Exercise resistance-compliance time was longer in pre-capillary PH associated with larger increases in diastolic pressure gradient. Conversely, resistance-compliance time was shortest in post-capillary PH compared to pre-capillary PH and NOR-HD and associated with limited increases in exercise diastolic pressure gradient. During steady-state, modest-intensity exercise-specific patterns of pulmonary vascular afterload responses were observed in pre- and post-capillary PH relative to NOR-HD. Longer resistance-compliance time related to greater increases in PA diastolic pressure and diastolic pressure gradients in pre-capillary PH, while shorter resistance-compliance time appeared to limit these increases in post-capillary PH.

Mesenchymal Stem Cell-Derived Extracellular Vesicles Therapy for Pulmonary Hypertension: A Comprehensive Review of Preclinical Studies

Pulmonary hypertension (PH) is a type of clinical pathophysiological syndrome characterized by a progressive increase in pulmonary vascular resistance and subsequent progressive failure of the right heart function, and is a common complication of many diseases. Mesenchymal stem cells (MSCs) autonomously home to sites damaged by disease, repair damaged tissues, and participate in the regulation of systemic inflammation and immune responses, which have good clinical application prospects. Extracellular vesicles (EVs), such as exosomes and microvesicles, participate in various biological activities by regulating intercellular communication. Exosomes secreted into the extracellular environment also affect the host immune system. MSC-derived extracellular vesicles (MSC-EVs), as a mediator in the paracrine processes of MSCs, carry biologically active substances such as proteins, lipids, mRNA, and micro-RNA. MSC-EVs therapies, safer than cell-based treatments, have been shown to be effective in modulating macrophages to support anti-inflammatory phenotypes, which are strongly related to histological and functional benefits in preclinical models of pulmonary hypertension. The main effects of active substances and their potential medical value have attracted wide attention from researchers. This article reviews the role and relevant mechanisms of MSC-EVs in the treatment of pulmonary hypertension in recent studies and provides a basis for their future clinical applications.

[Functional characterization of patients with isolated post-capillary or combined post-capillary and pre-capillary pulmonary hypertension]

BACKGROUND

 The World Conference on PH recommended differentiation of isolated postcapillary (Ipc) and combined post- and precapillary (Cpc) PH according to pulmonary vascular resistance alone. The aim of this study was the haemodynamic and functional characterization of patients diagnosed IpcPH and CpcPH according to the current recommendation of the latest World Symposium on Pulmonary Hypertension (PH) with an exploratory data analysis.

METHODS

 We evaluated all consecutive patients presenting at the PH outpatient clinic of Mission Medical Hospital from 2008-2015. All received a complete diagnostic work-up according to the guidelines. We analyzed data of patients with mPAP ≥ 25 mmHg and pulmonary capillary wedge pressure (PCWP  > 15 mmHg. We compared anthropometric, hemodynamic and functional data of six-minute walking test (6 MWT), cardiopulmonary exercise testing (CPET) and echocardiography of patients with IpcPH and CpcPH.

RESULTS

 Out of 726 patients 58 showed a postcapillary PH: IpcPH: n = 20; CpcPH: n = 38. Patients with IpcPH had a significantly lower mPAP and PVR than patients with CpcPH. Cardiac index was lower in the Cpc-PH group compared to the IpcPH group. Functional capacity did not differ. CpcPH patients showed a higher right/left atrial area (RA/LA)-ratio.

DISCUSSION AND CONCLUSION

Although CpcPH patients showed higher values of mPAP and PVR functional capacity was not worse than in patients with IpcPH. In patients with PH due to left heart disease an elevated RA/LA ratio may indicate CpcPH and invasive diagnostic work-up should be considered.

Clinical value of lncRNA SOX2-OT in pulmonary arterial hypertension and its role in pulmonary artery smooth muscle cell proliferation, migration, apoptosis, and inflammatory

BACKGROUND

Non-coding RNA is confirmed to be involved in pulmonary arterial hypertension (PAH).

OBJECTIVES

This study investigated the clinical value and potential mechanisms of the long noncoding RNA (lncRNA) SRY-box transcription factor 2 overlapping transcript (SOX2-OT) in PAH.

METHODS

SOX2-OT levels were measured by quantitative real-time polymerase chain reaction (qRT-PCR) in serum of 82 patients with PAH and 76 healthy controls. Receiver operating characteristic (ROC) analysis was performed to assess the diagnostic value of SOX2-OT. Human pulmonary arterial smooth muscle cells (hPASMCs) were treated by hypoxia to construct PAH cell models. Proliferation, migration, apoptosis, and inflammatory cytokines levels of hPASMCs were examined by CCK-8, Transwell, flow cytometry, and ELISA assay. Dual-luciferase reporter gene assays were performed to verify the target relationships between miR-455-3p and SOX2-OT, as well as small ubiquitin-related modifier 1 (SUMO1).

RESULTS

Serum SOX2-OT was highly expressed in patients with PAH (P < 0.05). And elevated SOX2-OT levels significantly differentiated PAH patients from healthy controls, confirming high diagnostic feasibility. What's more, SOX2-OT was increased in hypoxia-induced hPASMCs in a time-dependent manner. Silencing SOX2-OT could reverse hypoxia-induced proliferation, migration, anti-apoptosis, and inflammation of hPASMCs (P < 0.05). However, rescue experiments showed that this reversal effect of silencing SOX2-OT was attenuated by suppressed miR-455-3p, which was presumably achieved by SUMO1 (P < 0.05).

CONCLUSIONS

Elevated SOX2-OT is a feasible diagnostic marker for PAH, and its silencing may attenuated hypoxia-induced hPASMCs proliferation, migration, anti-apoptosis, and inflammation by modulating the miR-455-3p/SUMO1 axis, preventing vascular remodeling and PAH progression. Our research provided new insights for PAH treatment.

Association between income and likelihood of right heart catheterization in individuals with pulmonary hypertension: A US claims database analysis

We used a US-based administrative claims database to determine associations between annual household income and the likelihood of right heart catheterization (RHC) among individuals with pulmonary hypertension. Those with annual household income < $40,000 were 19% less likely to receive RHC compared to individuals with annual household income ≥ $100,000 (p < 0.0001).

Successful Early Immunosuppressive Therapy for Pulmonary Arterial Hypertension Due to Takayasu arteritis: Two Case Reports and a Review of Similar Case Reports in the English Literature

The efficacy of early immunosuppressive therapy without invasive therapy, such as endovascular or surgical revascularization, for pulmonary hypertension due to Takayasu arteritis (TAK-PH) remains to be elucidated. We herein report two cases of TAK-PH due to pulmonary arteritis successfully treated with early immunosuppressive therapy. A literature review of 42 cases of TAK-PH with pulmonary artery involvement showed that the cases treated with immunosuppressive therapy early after the onset (within 12 months) had a higher erythrocyte sedimentation rate and better outcome without invasive therapy than those treated later. TAK-PH may be successfully treated with immunosuppressive therapy without invasive therapy when diagnosed early with high disease activity.

Perfusion imaging heterogeneity during NO inhalation distinguishes pulmonary arterial hypertension (PAH) from healthy subjects and has potential as an imaging biomarker

BACKGROUND

Without aggressive treatment, pulmonary arterial hypertension (PAH) has a 5-year mortality of approximately 40%. A patient's response to vasodilators at diagnosis impacts the therapeutic options and prognosis. We hypothesized that analyzing perfusion images acquired before and during vasodilation could identify characteristic differences between PAH and control subjects.

METHODS

We studied 5 controls and 4 subjects with PAH using HRCT and ¹³NN PET imaging of pulmonary perfusion and ventilation. The total spatial heterogeneity of perfusion (CV²_Qtotal) and its components in the vertical (CV²_Qvgrad) and cranio-caudal (CV²_Qzgrad) directions, and the residual heterogeneity (CV²_Qr), were assessed at baseline and while breathing oxygen and nitric oxide (O₂ + iNO). The length scale spectrum of CV²_Qr was determined from 10 to 110 mm, and the response of regional perfusion to O₂ + iNO was calculated as the mean of absolute differences. Vertical gradients in perfusion (Q_vgrad) were derived from perfusion images, and ventilation-perfusion distributions from images of ¹³NN washout kinetics.

RESULTS

O₂ + iNO significantly enhanced perfusion distribution differences between PAH and controls, allowing differentiation of PAH subjects from controls. During O₂ + iNO, CV²_Qvgrad was significantly higher in controls than in PAH (0.08 (0.055-0.10) vs. 6.7 × 10^-3 (2 × 10^-4-0.02), p < 0.001) with a considerable gap between groups. Q_vgrad and CV²_Qtotal showed smaller differences: - 7.3 vs. - 2.5, p = 0.002, and 0.12 vs. 0.06, p = 0.01. CV²_Qvgrad had the largest effect size among the primary parameters during O₂ + iNO. CV²_Qr, and its length scale spectrum were similar in PAH and controls. Ventilation-perfusion distributions showed a trend towards a difference between PAH and controls at baseline, but it was not statistically significant.

CONCLUSIONS

Perfusion imaging during O2 + iNO showed a significant difference in the heterogeneity associated with the vertical gradient in perfusion, distinguishing in this small cohort study PAH subjects from controls.

[Functional characterization of patients with isolated post-capillary or combined post-capillary and pre-capillary pulmonary hypertension]

BACKGROUND

The World Conference on PH recommended differentiation of isolated postcapillary (Ipc) and combined post- and precapillary (Cpc) PH according to pulmonary vascular resistance alone. The aim of this study was the haemodynamic and functional characterization of patients diagnosed IpcPH and CpcPH according to the current recommendation of the latest World Symposium on Pulmonary Hypertension (PH) with an exploratory data analysis.

METHODS

We evaluated all consecutive patients presenting at the PH outpatient clinic of Mission Medical Hospital from 2008-2015. All received a complete diagnostic work-up according to the guidelines. We analyzed data of patients with mPAP≥ 25 mmHg and pulmonary capillary wedge pressure (PCWP) > 15 mmHg. We compared anthropometric, hemodynamic and functional data of six-minute walking test (6 MWT), cardiopulmonary exercise testing (CPET) and echocardiography of patients with IpcPH and CpcPH.

RESULTS

Out of 726 patients 58 showed a postcapillary PH: IpcPH: n = 20; CpcPH: n = 38. Patients with IpcPH had a significantly lower mPAP and PVR than patients with CpcPH. Cardiac index was lower in the Cpc-PH group compared to the IpcPH group. Functional capacity did not differ. CpcPH patients showed a higher right/left atrial area (RA/LA)-ratio.

DISCUSSION AND CONCLUSION

Although CpcPH patients showed higher values of mPAP and PVR functional capacity was not worse than in patients with IpcPH. In patients with PH due to left heart disease an elevated RA/LA ratio may indicate CpcPH and invasive diagnostic work-up should be considered.

In systemic sclerosis TAPSE/sPAP ratio can be used in addition to the DETECT algorithm for pulmonary arterial hypertension diagnosis

OBJECTIVE

Early detection of pulmonary arterial hypertension (PAH) is crucial to improve patient outcomes. The aim of this study was to compare the positive predictive value (PPV) between the echocardiography-derived tricuspid annular plane systolic excursion/systolic pulmonary artery pressure (TAPSE/sPAP) ratio and the DETECT algorithm for PAH screening in a cohort of systemic sclerosis (SSc) patients.

METHODS

51 SSc patients were screened for PAH using DETECT algorithm and echocardiography.

RESULTS

Echocardiography was recommended by the DETECT algorithm step 1 in 34 patients (66.7%). Right heart catheterization (RHC) was recommended by the DETECT algorithm step 2 in 16 patients (31.4%). PAH was confirmed by RHC in 5 patients. DETECT algorithm positive predictive value (PPV) was 31.3%.TAPSE/sPAP ratio was higher in SSc patients not referred for RHC than in SSc patients referred for RHC according to DETECT algorithm step 2 [0.83 (0.35-1.40) mm/mmHg vs 0.74 (0.12-1.09) mm/mmHg, p < 0.05]. Using a cut-off of 0.60 mm/mmHg, 8 (15.7%) SSc patients had a TAPSE/sPAP ratio ≤0.60 mm/mmHg. PAH was confirmed by RHC in 5 patients. PPV of TAPSE/sPAP was 62.5%.In multiple regression analysis, TAPSE/sPAP was associated with age (β coefficient = -0.348 [95% CI, -0.011 to -0.003]; p < 0.01), DETECT algorithm step 1 (β coefficient = 1.023 [95% CI, 0.006-0.024]; p < 0.01) and DETECT algorithm step 2 (β coefficient = -1.758 [95% CI, -0.059 to -0.021]; p < 0.0001).

CONCLUSION

In SSc patients with a DETECT algorithm step 2 total score >35 the TAPSE/sPAP ratio can be used to further select patients requiring RHC to confirm PAH diagnosis.

Vascular remodeling of the small pulmonary arteries and measures of vascular pruning on computed tomography

Pulmonary hypertension is characterized histologically by intimal and medial thickening in the small pulmonary arteries, eventually resulting in vascular "pruning." Computed tomography (CT)-based quantification of pruning is associated with clinical measures of pulmonary hypertension, but it is not established whether CT-based pruning correlates with histologic arterial remodeling. Our sample consisted of 138 patients who underwent resection for early-stage lung adenocarcinoma. From histologic sections, we identified small pulmonary arteries and measured the relative area comprising the intima and media (VWA%), with higher VWA% representing greater histologic remodeling. From pre-operative CTs, we used image analysis algorithms to calculate the small vessel volume fraction (BV5/TBV) as a CT-based indicator of pruning (lower BV5/TBV represents greater pruning). We investigated relationships of CT pruning and histologic remodeling using Pearson correlation, simple linear regression, and multivariable regression with adjustment for age, sex, height, weight, smoking status, and total pack-years. We also tested for effect modification by sex and smoking status. In primary models, more severe CT pruning was associated with greater histologic remodeling. The Pearson correlation coefficient between BV5/TBV and VWA% was -0.41, and in linear regression models, VWA% was 3.13% higher (95% CI: 1.95-4.31%, p < 0.0001) per standard deviation lower BV5/TBV. This association persisted after multivariable adjustment. We found no evidence that these relationships differed by sex or smoking status. Among individuals who underwent resection for lung adenocarcinoma, more severe CT-based vascular pruning was associated with greater histologic arterial remodeling. These findings suggest CT imaging may be a non-invasive indicator of pulmonary vascular pathology.

Prognostic value of 6-min walk stress echocardiography in patients with interstitial lung disease

BACKGROUND

The 6-min walk test (6MWT) provides prognostic information for patients with interstitial lung disease (ILD). Parameter determined by Doppler echocardiography after the 6MWT (6 MW stress echocardiography) is shown to be a predictor of future development of pulmonary hypertension in patients with connective tissue disease. However, the clinical utility of 6 MW stress echocardiography in predicting cardiopulmonary events in patients with ILD remains unknown. We examined whether parameters determined by 6 MW stress echocardiography independent predictors of adverse events in patients with ILD.

METHODS

Echocardiographic examinations were performed in 68 consecutively enrolled patients with ILD (age, 65 ± 10 years, 65% men). A pressure gradient of tricuspid regurgitation (TRPG) and pulmonary vascular resistance (PVRecho) calculated using the following formula [PVRecho = (peak velocity of TR × 10/time-velocity integral of right ventricular outflow (RVOT-VTI)) + 0.16] were measured at baseline and at post 6MWT. Data for parameters of pulmonary functional tests and for 6MWT were collected.

RESULTS

During a mean follow-up period of 22 ± 12 months, 22 patients experienced cardiopulmonary events. In univariate analysis, %VC, TRPG, PVRecho, TRPG post 6MWT, and PVRecho post 6MWT were significantly associated with cardiopulmonary events. Multivariate analysis using the Cox proportional hazards model indicated that %VC [hazard ratio (HR): 0.97, p = 0.009] and PVRecho post 6MWT (HR: 1.77, p = 0.004) were independent predictors of cardiopulmonary events in patients with ILD.

CONCLUSIONS

In addition to parameters of pulmonary function tests, increased PVRecho post 6MWT is a significant predictor of cardiopulmonary events in patients with ILD. A 6 MW stress echocardiography is useful in assessing the risk of adverse events in patients with ILD.

Dyspnoea and diffuse pulmonary nodules in a patient with pulmonary veno-occlusive disease: a case report and literature review

Pulmonary veno-occlusive disease (PVOD) is a rare type of pulmonary hypertension characterized by capillary damage or arterial pulmonary hypertension. Early lung transplantation is the only effective treatment for PVOD because of the lack of specificity in its clinical manifestations and its rapid progression and poor prognosis. A 28-year-old woman presented with exertional dyspnoea. A chest computed tomography scan revealed diffuse centrilobular ground glass opacities in both lungs, a ratio of the transverse diameter of the main pulmonary trunk to the ascending aorta of >1, and enlargement of the right ventricle and right atrium. A right atrial floating catheter test showed right ventricular pressure of 82/0/4 mmHg, mean pulmonary artery pressure of 83/34/53 mmHg, and pulmonary artery wedge pressure of 15/8/12 mmHg. A mutation was found in the eukaryotic translation initiation factor 2 alpha kinase 4 (EIF2AK4) gene. Thus, the patient was diagnosed with PVOD and subsequently given standard bosentan treatment (62.5 mg twice a day). However, after 6 months of follow-up, there was no significant improvement in the pulmonary artery pressure or activity tolerance (6-minute walking test). Therefore, cardiopulmonary transplantation was performed. Early diagnosis and timely treatment of PVOD may improve the patient’s prognosis.

Cardiopulmonary Hemodynamics in Pulmonary Hypertension and Heart Failure: JACC Review Topic of the Week

Pulmonary hypertension (PH) is an independent risk factor for adverse clinical outcome, particularly in left heart disease (LHD) patients. Recent advances have clarified the mean pulmonary artery pressure (mPAP) range that is above normal and is associated with clinical events, including mortality. This progress has for the first time resulted in a new clinical definition of PH that is evidenced-based, is inclusive of mPAP >20 mm Hg, and emphasizes early diagnosis. Additionally, pulmonary vascular resistance (PVR) 2.2 to 3.0 WU, considered previously to be normal, appears to associate with elevated clinical risk. A revised approach to classifying PH patients as pre-capillary, isolated post-capillary, or combined pre-/post-capillary PH now guides point-of-care diagnosis, risk stratification, and treatment. Exercise hemodynamic or confrontational fluid challenge studies may also aid decision-making for patients with PH-LHD or otherwise unexplained dyspnea. This collective progress in pulmonary vascular and heart failure medicine reinforces the critical importance of accurate hemodynamic assessment.

EmPHasis-10 health-related quality of life score predicts outcomes in patients with idiopathic and connective tissue disease-associated pulmonary arterial hypertension: results from a UK multicentre study

Health-related quality of life (HRQoL) scores assess symptom burden in pulmonary arterial hypertension (PAH) but data regarding their role in prognostication and risk stratification are limited. We assessed these relationships using the emPHasis-10 HRQoL measure.1745 patients with idiopathic PAH (IPAH), drug-induced PAH (DPAH), heritable PAH (HPAH) (collectively "(I/D/H)PAH"), or connective tissue disease-associated PAH (CTD-PAH), who had completed emPHasis-10 questionnaires at one of six UK referral centres between 2014 and 2017, were identified. Correlations with exercise capacity and World Health Organization (WHO) functional class were assessed, and exploratory risk stratification thresholds were tested.Moderate correlations were seen between emPHasis-10 scores and 6-min walk distance (r=-0.546), incremental shuttle walk distance (r=-0.504) and WHO functional class (r=0.497) (all p<0.0001). Distribution of emPHasis-10 score differed significantly between each WHO functional class (all p<0.0001). On multivariate analysis, emPHasis-10 score, but not WHO functional class, was an independent predictor of mortality. In a risk stratification approach, scores of 0-16, 17-33 and 34-50 identified incident patients with 1-year mortality of 5%, 10% and 23%, respectively. Survival of patients in WHO functional class III could be further stratified using an emPHasis-10 score ≥34 (p<0.01). At follow-up, patients with improved emPHasis-10 scores had improved exercise capacity (p<0.0001) and patients who transitioned between risk groups demonstrated similar survival to patients originally in those risk groups.The emPHasis-10 score is an independent prognostic marker in patients with (I/D/H)PAH or CTD-PAH. It has utility in risk stratification in addition to currently used parameters. Improvement in emPHasis-10 score is associated with improved exercise capacity.

Vascular Pruning on CT and Interstitial Lung Abnormalities in the Framingham Heart Study

BACKGROUND

Pulmonary vascular disease is associated with poor outcomes in individuals affected by interstitial lung disease. The pulmonary vessels can be quantified with noninvasive imaging, but whether radiographic indicators of vasculopathy are associated with early interstitial changes is not known.

RESEARCH QUESTION

Are pulmonary vascular volumes, quantified from CT scans, associated with interstitial lung abnormalities (ILA) in a community-based sample with a low burden of lung disease?

STUDY DESIGN AND METHODS

In 2,386 participants of the Framingham Heart Study, we used CT imaging to calculate pulmonary vascular volumes, including the small vessel fraction (a surrogate of vascular pruning). We constructed multivariable logistic regression models to investigate associations of vascular volumes with ILA, progression of ILA, and restrictive pattern on spirometry. In secondary analyses, we additionally adjusted for diffusing capacity and emphysema, and performed a sensitivity analysis restricted to participants with normal FVC and diffusing capacity.

RESULTS

In adjusted models, we found that lower pulmonary vascular volumes on CT were associated with greater odds of ILA, antecedent ILA progression, and restrictive pattern on spirometry. For example, each SD lower small vessel fraction was associated with 1.81-fold greater odds of ILA (95% CI, 1.41-2.31; P < .0001), and 1.63-fold greater odds of restriction on spirometry (95% CI, 1.18-2.24; P = .003). Similar patterns were seen after adjustment for diffusing capacity for carbon monoxide, emphysema, and among participants with normal lung function.

INTERPRETATION

In this cohort of community-dwelling adults not selected on the basis of lung disease, more severe vascular pruning on CT was associated with greater odds of ILA, ILA progression, and restrictive pattern on spirometry. Pruning on CT may be an indicator of early pulmonary vasculopathy associated with interstitial lung disease.

Perinuclear anti-neutrophil cytoplasmic antibody in systemic lupus erythematosus indicates more severe condition

OBJECTIVE

To investigate the clinical significance of perinuclear anti-neutrophil cytoplasmic antibody (p-ANCA) in patients with systemic lupus erythematosus (SLE).

METHODS

This retrospective study included 120 SLE patients. All patients were divided into group p-ANCA+ and group p-ANCA-. Demographic characteristics, clinical symptoms, autoantibodies, laboratory tests and renal pathology were compared between these two groups.

RESULTS

Among 120 patients, 45 (37.5%) patients were p-ANCA+ and 75 (62.5%) patients were p-ANCA-. The occurrence of lupus nephritis was significantly higher in group p-ANCA+ (P = 0.046). For autoantibodies, the occurrences of anti-dsDNA, anti-nucleosome and anti-histone were significantly higher in group p-ANCA+ (P < 0.001, P = 0.004 and P = 0.006, respectively). Titers of anti-dsDNA antibody, erythrocyte sedimentation rate (ESR), serum beta-2-microglobulin (β2-MG) and systemic lupus erythematosus disease activity index (SLEDAI) were higher in group p-ANCA+ (P < 0.001, P = 0.021, P < 0.001 and P = 0.005, respectively), while albumin was significantly lower than p-ANCA- group (P = 0.012). There were no differences in the classification of lupus nephritis, activity index and chronicity index. p-ANCA correlated with lupus nephritis, anti-dsDNA antibody, anti-nucleosome antibody and anti-histone antibody, and also disease activity markers, such as titers of anti-dsDNA antibody, ESR, albumin, serum β2-MG and SLEDAI.

CONCLUSION

The appearance of p-ANCA in SLE indicated high probability of lupus nephritis and more severe condition.

Epigenetic Regulation of Pulmonary Arterial Hypertension-Induced Vascular and Right Ventricular Remodeling: New Opportunities?

Pulmonary artery hypertension (PAH) is a rare chronic disease with high impact on patients’ quality of life and currently no available cure. PAH is characterized by constant remodeling of the pulmonary artery by increased proliferation and migration of pulmonary arterial smooth muscle cells (PASMCs), fibroblasts (FBs) and endothelial cells (ECs). This remodeling eventually leads to increased pressure in the right ventricle (RV) and subsequent right ventricle hypertrophy (RVH) which, when left untreated, progresses into right ventricle failure (RVF). PAH can not only originate from heritable mutations, but also develop as a consequence of congenital heart disease, exposure to drugs or toxins, HIV, connective tissue disease or be idiopathic. While much attention was drawn into investigating and developing therapies related to the most well understood signaling pathways in PAH, in the last decade, a shift towards understanding the epigenetic mechanisms driving the disease occurred. In this review, we reflect on the different epigenetic regulatory factors that are associated with the pathology of RV remodeling, and on their relevance towards a better understanding of the disease and subsequently, the development of new and more efficient therapeutic strategies.

Genetic Evaluation in a Cohort of 126 Dutch Pulmonary Arterial Hypertension Patients

Pulmonary arterial hypertension (PAH) is a severe, life-threatening disease, and in some cases is caused by genetic defects. This study sought to assess the diagnostic yield of genetic testing in a Dutch cohort of 126 PAH patients. Historically, genetic testing in the Netherlands consisted of the analysis of BMPR2 and SMAD9. These genes were analyzed in 70 of the 126 patients. A (likely) pathogenic (LP/P) variant was detected in 22 (31%) of them. After the identification of additional PAH associated genes, a next generation sequencing (NGS) panel consisting of 19 genes was developed in 2018. Additional genetic testing was offered to the 48 BMPR2 and SMAD9 negative patients, out of which 28 opted for NGS analysis. In addition, this gene panel was analyzed in 56 newly identified idiopathic (IPAH) or pulmonary veno occlusive disease (PVOD) patients. In these 84 patients, NGS panel testing revealed LP/P variants in BMPR2 (N = 4), GDF2 (N = 2), EIF2AK4 (N = 1), and TBX4 (N = 3). Furthermore, 134 relatives of 32 probands with a LP/P variant were tested, yielding 41 carriers. NGS panel screening offered to IPAH/PVOD patients led to the identification of LP/P variants in GDF2, EIF2AK4, and TBX4 in six additional patients. The identification of LP/P variants in patients allows for screening of at-risk relatives, enabling the early identification of PAH.

Cardiopulmonary exercise testing in a combined screening approach to individuate pulmonary arterial hypertension in systemic sclerosis

Objectives

The DETECT algorithm has been developed to identify SSc patients at risk for pulmonary arterial hypertension (PAH) yielding high sensitivity but low specificity, and positive predictive value. We tested whether cardiopulmonary exercise testing (CPET) could improve the performance of the DETECT screening strategy.

Methods

Consecutive SSc patients over a 30-month period were screened with the DETECT algorithm and positive subjects were referred for CPET before the execution of right-heart catheterization. The predictive performance of CPET on top of DETECT was evaluated and internally validated via bootstrap replicates.

Results

Out of 314 patients, 96 satisfied the DETECT application criteria and 54 were positive. PAH was ascertained in 17 (31.5%) and pre-capillary pulmonary hypertension in 23 (42.6%) patients. Within CPET variables, the slope of the minute ventilation to carbon dioxide production relationship (VE/VCO₂ slope) had the best performance to predict PAH at right-heart catheterization [median (interquartile range) of specificity 0.778 (0.714–0.846), positive predictive value 0.636 (0.556–0.750)]; exploratory analysis on pre-capillary yielded a specificity of 0.714 (0.636–0.8) and positive predictive value of 0.714 (0.636–0.8).

Conclusion

In association with the DETECT algorithm, CPET may be considered as a useful tool in the workup of SSc-related pulmonary hypertension. The sequential determination of the VE/VCO₂ slope in DETECT-positive subjects may reduce the number of unnecessary invasive procedures without any loss in the capability to capture PAH. This strategy had also a remarkable performance in highlighting the presence of pre-capillary pulmonary hypertension.

Pulmonary Vascular Disease and Cardiopulmonary Exercise Testing

Cardiopulmonary exercise testing (CPET) is of great interest and utility for clinicians dealing Pulmonary Hypertension (PH) in several ways, including: helping with differential diagnosis, evaluating exercise intolerance and its underpinning mechanisms, accurately assessing exertional dyspnea and unmasking its underlying often non-straightforward mechanisms, generating prognostic indicators. Pathophysiologic anomalies in PH can range from reduced cardiac output and aerobic capacity, to inefficient ventilation, dyspnea, dynamic hyperinflation, and locomotor muscle dysfunction. CPET can magnify the PH-related pathophysiologic anomalies and has a major role in the management of PH patients.

Pulmonary arterial hypertension with below threshold pulmonary vascular resistance

Pulmonary vascular resistance (PVR) >3 Wood units is a criterion of the haemodynamic definition of pulmonary arterial hypertension (PAH). However, this cut-off is conservative and arbitrarily defined. Data is lacking on the natural history, response to therapy and survival of patients diagnosed with precapillary pulmonary hypertension (PH) with mild or borderline elevation of PVR.In Australia, PAH therapy could be prescribed solely on mean pulmonary arterial pressure (PAP) and pulmonary arterial wedge pressure (PAWP) criteria. Using the Australian and New Zealand Pulmonary Hypertension Registry, we aimed to study a population diagnosed with PAH between January 2004 and December 2017 with the pre-defined haemodynamic characteristics of mean PAP ≥25 mmHg, PAWP ≤15 mmHg and PVR <3 Wood units.Eighty-two patients met the pre-defined haemodynamic inclusion criteria (mean age 63±11 years; 67 females). Underlying aetiologies included idiopathic disease (n=39), connective tissue disease (CTD; n=42) and HIV infection (n=1). At diagnosis, mean PAP was 27 mmHg (interquartile range (IQR) 25-30 mmHg), PAWP 13 mmHg (IQR 11-14 mmHg) and PVR 2.2 Wood units (IQR 1.9-2.7 Wood units). Baseline 6-min walk distance (6MWD) was 352 m (IQR 280-416 m) and 77% of subjects were in New York Heart Association (NYHA) functional class 3 or 4. All patients were commenced on initial monotherapy with an endothelin receptor antagonist (ERA; n=66) or phosphodiesterase type-5 inhibitor (PDE5i; n=16). At first re-evaluation, 6MWD increased by 46 m (IQR 7-96 m) and 35% of subjects demonstrated improvement in NYHA functional class. After a median follow-up of 65 months (IQR 32-101 months), 18 out of 82 subjects (22.0%) had died, with estimated 1-year and 5-year survival rates of 98% and 84%, respectively. Death attributed to PAH occurred in six out of these 18 patients (33.3%, 7% of total cohort).Patients with precapillary PH and "borderline" PVR falling outside the current definition have adverse outcomes. Such patients appear to respond to PAH therapy; however, this requires further study in randomised trials.

Reduced pulmonary vascular reserve during stress echocardiography in confirmed pulmonary hypertension and patients at risk of overt pulmonary hypertension

Noninvasive estimation of systolic pulmonary artery pressure (SPAP) during exercise stress echocardiography (ESE) is recommended for pulmonary hemodynamics evaluation but remains flow-dependent. Our aim was to assess the feasibility of pulmonary vascular reserve index (PVRI) estimation during ESE combining SPAP with cardiac output (CO) or exercise-time and compare its value in three group of patients: with invasively confirmed pulmonary hypertension (PH), at risk of PH development (PH risk) mainly with systemic sclerosis and in controls (C) without clinical risk factors for PH, age-matched with PH risk patients. We performed semisupine ESE in 171 subjects: 31 PH, 61 PH at risk and 50 controls as well as in 29 young, healthy normals. Rest and stress assessment included: tricuspid regurgitant flow velocity (TRV), pulmonary acceleration time (ACT), CO (Doppler-estimated). SPAP was calculated from TRV or ACT when TRV was not available. We estimated PVRI based on CO (peak CO/SPAP*0.1) or exercise-time (ESE time/SPAP*0.1). During stress, TRV was measurable in 44% patients ACT in 77%, either one in 95%. PVRI was feasible in 65% subjects with CO and 95% with exercise-time (p < 0.0001). PVRI was lower in PH compared to controls both for CO-based PVRI (group 1 = 1.0 ± 0.95 vs group 3 = 4.28 ± 2.3, p < 0.0001) or time-based PVRI estimation (0.66 ± 0.39 vs 3.95 ± 2.26, p < 0.0001). The proposed criteria for PH detection were for CO-based PVRI ≤ 1.29 and ESE-time based PVRI ≤ 1.0 and for PH risk ≤ 1.9 and ≤ 1.7 respectively. Noninvasive estimation of PVRI can be obtained in near all patients during ESE, without contrast administration, integrating TRV with ACT for SPAP assessment and using exercise time as a proxy of CO. These indices allow for comparison of pulmonary vascular dynamics in patients with varied exercise tolerance and clinical status.