The 6th World Symposium on Pulmonary Hypertension: what's old is new

Effect of Group 2 Pulmonary Hypertension Subgroups on Outcomes: Impact of the Updated Definition of Pulmonary Hypertension

BACKGROUND

Pulmonary hypertension (PH) is a common complication of end-stage heart failure (ESHF) and associated with increased mortality. The definition of PH has recently been changed from a mean pulmonary arterial pressure (PAPm) ≥25 mmHg to a PAPm >20 mmHg. Since this change, there are no data evaluating group 2 PH subgroups on outcomes. The purpose of this study was to determine the impact of updated group 2 PH subgroups on outcomes, as well as to evaluate the clinical, echocardiographic, and haemodynamic characteristics of subgroups, and determine predictors of PH in patients with ESHF.

METHOD

A total of 416 patients with ESHF with left ventricle ejection fraction (LVEF) ≤25% were divided into three groups. Pulmonary hypertension was defined as PAPm >20 mmHg. Primary outcome was defined as left ventricular assist device (LVAD) implantation, urgent heart transplantation (HT), or death. Secondary outcome was defined as LVAD implantation and HT.

RESULTS

Over a median follow-up of 503.5 days, combined pre- and postcapillary PH (Cpc-PH) displayed greater risk of primary outcome than those with isolated postcapillary (Ipc-PH) (hazard ratio [HR], 1.57; 95% confidence interval [CI], 1.29-1.91; p<0.001) and those with no PH (HR, 2.47; 95% CI, 1.68-3.63; p<0.001). Patients with Ipc-PH demonstrated greater risk than those with no PH (HR, 1.57; 95% CI, 1.57-1.90; p<0.001). Likelihood ratios of updated PH criteria and old PH criteria (PAPm ≥25 mmHg) in identifying primary outcome were 75.6 (R²=0.179) and 72.09 (R²=0.164). Patients with PAPm 21-24 mmHg had a higher primary outcome than those with PAPm ≤20 mmHg. Severe mitral regurgitation, LVEF, grade 3 diastolic dysfunction, diabetes, and cardiac output were predictors of PH.

CONCLUSIONS

Pulmonary hypertension increases the risk of LVAD, urgent HT, or death, and Cpc-PH further increases risk in patients with ESHF. Compared to the previous definition, a new PH definition better discriminates death, going to urgent HT, or LVAD implantation for PH subgroups.

"NOVEL MECHANISMS TARGETED BY DRUG TRIALS IN PULMONARY ARTERIAL HYPERTENSION"

Pulmonary arterial hypertension (PAH) is a rare disease associated with abnormally elevated pulmonary pressures and right heart failure resulting in high morbidity and mortality. While PAH prognosis has improved with the introduction of pulmonary vasodilators, disease progression remains a major problem. Given that available therapies are inadequate for preventing small vessel loss and obstruction, there is an active interest in identifying drugs capable of targeting angiogenesis and mechanisms involved in regulation of cell growth and fibrosis. Among the mechanisms linked to PAH pathogenesis, recent preclinical studies have identified promising compounds that are currently being tested in clinical trials. These drugs target seven of the major mechanisms associated with PAH pathogenesis: BMP signaling, tyrosine kinase receptors, estrogen metabolism, extracellular matrix, angiogenesis, epigenetics, and serotonin metabolism. In this review, we will discuss the preclinical studies that led to prioritization of these mechanisms and will discuss recently completed and ongoing phase 2/3 trials using novel interventions such as sotatercept, anastrozole, rodatristat ethyl, tyrosine kinase inhibitors, and endothelial progenitor cells among others. We anticipate that the next generation of compounds will build upon the success of the current standard of care and improve clinical outcomes and quality of life of patients afflicted with PAH.

Case Report: BMPR2-Targeted MinION Sequencing as a Tool for Genetic Analysis in Patients With Pulmonary Arterial Hypertension

Background: Mutations in the bone morphogenetic protein receptor type 2 gene (BMPR2) represent a major genetic cause of pulmonary arterial hypertension (PAH). Identification of BMPR2 mutations is crucial for the genetic diagnosis of PAH. MinION nanopore sequencer is a portable third-generation technology that enables long-read sequencing at a low-cost. This nanopore technology-based device has not been used previously for PAH diagnosis. This study aimed to determine the feasibility of using MinION nanopore sequencing for the genetic analysis of PAH patients, focused on BMPR2.

Methods: We developed a protocol for the custom bioinformatics pipeline analysis of long reads generated by long-PCR. To evaluate the potential of using MinION sequencing in PAH, we analyzed five samples, including those of two idiopathic PAH patients and a family of three members with one affected patient. Sanger sequencing analysis was performed to validate the variants.

Results: The median read length was around 3.4 kb and a good mean quality score of approximately 19 was obtained. The total number of reads generated was uniform among the cases and ranged from 2,268,263 to 3,126,719. The coverage was consistent across flow cells in which the average number of reads per base ranged from 80,375 to 135,603. We identified two polymorphic variants and three mutations in four out of five patients. Certain indel variant calling-related errors were observed, mostly outside coding sequences.

Conclusion: We have shown the ability of this portable nanopore sequencer to detect BMPR2 mutations in patients with PAH. The MinION nanopore sequencer is a promising tool for screening BMPR2 mutations, especially in small laboratories and research groups.

Unenhanced computed tomography as a diagnostic tool in suspected pulmonary hypertension: a retrospective cross-sectional pilot study

Background: Computed tomography pulmonary angiography (CTPA) has been proposed to be diagnostic for pulmonary hypertension (PH) in multiple studies. However, the utility of the unenhanced CT measurements diagnosing PH has not been fully assessed.  This study aimed to assess the diagnostic utility and reproducibility of cardiac and great vessel parameters on unenhanced computed tomography (CT) in suspected pulmonary hypertension (PH). Methods: In total, 42 patients with suspected PH who underwent unenhanced CT thorax and right heart catheterization (RHC) were included in the study. Three observers (a consultant radiologist, a specialist registrar in radiology, and a medical student) measured the parameters by using unenhanced CT. Diagnostic accuracy of the parameters was assessed by area under the receiver operating characteristic curve (AUC). Inter-observer variability between the consultant radiologist (primary observer) and the two secondary observers was determined by intra-class correlation analysis (ICC). Results: Overall, 35 patients were diagnosed with PH by RHC while 7 patients were not. Main pulmonary arterial (MPA) diameter was the strongest (AUC 0.79 to 0.87) and the most reproducible great vessel parameter. ICC comparing the MPA diameter measurement of the consultant radiologist to the specialist registrar’s and the medical student’s were 0.96 and 0.92, respectively. Right atrial area was the cardiac measurement with highest accuracy and reproducibility (AUC 0.76 to 0.79; ICC 0.980, 0.950) followed by tricuspid annulus diameter (AUC 0.76 to 0.79; ICC 0.790, 0.800). Conclusions: MPA diameter and right atrial areas showed high reproducibility. Diagnostic accuracies of these were within the range of acceptable to excellent, and might have clinical value. Tricuspid annular diameter was less reliable and less diagnostic and was therefore not a recommended diagnostic measurement.

Role of Selexipag in Chronic Obstructive Pulmonary Disease (COPD) Patients With Out-of-Proportion Pulmonary Hypertension

Pulmonary hypertension (PH) in patients with chronic obstructive pulmonary disease (COPD) is associated with an increase in the risk of COPD exacerbation, increased hospitalization, and worse survival in this patient population. No specific treatment is available for PH in COPD. However, reported out-of-proportion PH may benefit from a certain type of treatment. This study shows that the use of selexipag in the treatment of out-of-proportion PH in COPD patients was associated with an improvement in functional status evaluated by a six-minute walk test (6MWT) and a mean pulmonary artery pressure at 6 +/- 2 months of treatment.

Penetrance of Severe Pulmonary Arterial Hypertension in Response to Vascular Endothelial Growth Factor Receptor 2 Blockade in a Genetically Prone Rat Model Is Reduced by Female Sex

Background We have previously reported important strain differences in response to SU5416 (SU, a vascular endothelial growth factor receptor 2 inhibitor) in rats and have identified a specific colony of Sprague-Dawley rats that are hyperresponsive (SDHR) to SU alone and develop severe pulmonary arterial hypertension (PAH) with a single injection of SU, even in the absence of hypoxia. Interestingly, SDHR rats exhibit incomplete penetrance of the severe PAH phenotype with an "all-or-none" response to SU alone, which provides a unique opportunity to assess the influence of female sex and sex hormones on susceptibility to PAH after endothelial injury in a genetically prone model. Methods and Results SDHR rats were injected with SU (20 mg/kg SC) and, in the absence of hypoxia, 72% of male but only 27% of female rats developed severe PAH at 7 weeks, which was associated with persistent endothelial cell apoptosis. This sex difference in susceptibility for severe PAH was abolished by ovariectomy. Estradiol replacement, beginning 2 days before SU (prevention), inhibited lung endothelial cell apoptosis and completely abrogated severe PAH phenotype in both male and ovariectomized female rats, while progesterone was only protective in ovariectomized female rats. In contrast, delayed treatment of SDHR rats with established PAH with estradiol or progesterone (initiated at 4 weeks post-SU) failed to reduce lung endothelial cell apoptosis or improve PAH phenotype. Conclusions Female sex hormones markedly reduced susceptibility for the severe PAH phenotype in response to SU alone in a hyperresponsive rat strain by abolishing SU-induced endothelial cell apoptosis, but did not reverse severe PAH in established disease.

Evaluation and Management of Pulmonary Arterial Hypertension in Congenital Heart Disease

Pulmonary arterial hypertension is a common complication in patients with congenital heart disease (CHD), aggravating the natural course of the underlying defect. Pulmonary arterial hypertension (PAH) has a multifactorial etiology depending on the size and nature of the cardiac defect as well as environmental factors. Although progress has been made in disease-targeting therapy using pulmonary vasodilators to treat Eisenmenger syndrome, important gaps still exist in the evaluation and management of adult patients with CHD-associated PAH (PAH-CHD) who have systemic-to-pulmonary shunts. The choice of interventional, medical, or both types of therapy is an ongoing dilemma that requires further data. This review focuses on the evaluation and management of PAH-CHD in the contemporary era.

Effectiveness and safety of a simple home-based rehabilitation program in pulmonary arterial hypertension: an interventional pilot study

BACKGROUND

Rehabilitation plays an important role in the management of patients with pulmonary arterial hypertension (PAH) and current guidelines recommend implementation of a monitored individualized exercise training program as adjuvant therapy for stable PAH patients on optimal medical treatment. An optimal rehabilitation model for this group of patients has not yet been established. This randomized prospective study assessed the effectiveness and safety of a 6-month home-based caregiver-supervised rehabilitation program among patients with pulmonary arterial hypertension.

METHODS

A total of 39 patients with PAH were divided into two groups: intervention group (16 patients), subjected to a 6-month home-based physical training and respiratory rehabilitation program adapted to the clinical status of participants, and control group (23 patients) who did not perform physical training. The 6-min walk test (6MWT), measurement of respiratory muscle strength, quality of life assessment (SF-36, Fatigue Severity Scale - FSS) were performed before study commencement, and after 6 and 12 months. Adherence to exercise protocol and occurrence of adverse events were also assessed.

RESULTS

Physical training significantly improved 6MWT distance (by 71.38 ± 83.4 m after 6 months (p = 0.004), which remained increased after 12 months (p = 0.043), and respiratory muscle strength after 6 and 12 months (p < 0.01). Significant improvement in quality of life was observed after the training period with the use of the SF-36 questionnaire (Physical Functioning, p < 0.001; Role Physical, p = 0.015; Vitality, p = 0.022; Role Emotional, p = 0.029; Physical Component Summary, p = 0.005), but it did not persist after study completion. Adherence to exercise protocol was on average 91.88 ± 14.1%. No serious adverse events were noted.

CONCLUSION

According to study results, the home-based rehabilitation program dedicated to PAH patients is safe and effective. It improves functional parameters and quality of life. Strength of respiratory muscles and 6MWD remain increased 6 months after training cessation.

TRIAL REGISTRATION

ClinicalTrials.gov , NCT03780803 . Registered 12 December 2018.

Pulmonary Hypertension in 2021: Part I-Definition, Classification, Pathophysiology, and Presentation

The World Symposium on Pulmonary Hypertension (WSPH) was organized by the World Health Organization in 1973 in response to an increase in pulmonary arterial hypertension in Europe caused by aminorex, an appetite suppressant. The mandate of this meeting was to review the latest clinical and scientific research and to formulate recommendations to improve the diagnosis and management of pulmonary hypertension (PH).¹ Since 1998, the WSPH has met every five years and in 2018, the sixth annual WSPH revised the hemodynamic definition of PH. This two-part series will review the updated definition, classification, pathophysiology, presentation, diagnosis, management, and perioperative management of patients with PH. In the first part of this series, the definition, classification, pathophysiology, and presentation will be reviewed.

[Invasive hemodynamic monitoring by Swan-Ganz pulmonary artery catheter: concepts and utility]

Since its beginnings in the last century, pulmonary artery catheterization (PAC) has evolved into an invasive hemodynamic evaluation technique that can be performed at the patient's bedside through a Swan-Ganz catheter; this procedure has maintained an intermittent course in terms of its use; however, it has currently demonstrated relevance in specific scenarios. The PAC allows access to the central venous circulation, the right heart and the pulmonary artery; it performs the calculation of hemodynamic variables directly or indirectly by means of established formulas and methods. This makes possible to perform an adequate hemodynamic evaluation and classification, perform specific tests (e.g. vasoreactivity test), which help to define the diagnosis, therapeutic , monitor the response to treatment, evaluation prior to advanced therapies (e.g. cardiac transplantation or mechanical circulatory assistance devices), and prognosis in our patients. In this article we discuss the concepts and usefulness of pulmonary artery catheterization.

Potential Role of Cardiopulmonary Exercise Testing as an Early Screening Tool for Patients With Suspected Pulmonary Hypertension Including Exercise-Induced Pulmonary Hypertension: Results From a Retrospective Analysis

OBJECTIVE

The primary goal of our retrospective case-control study was to evaluate the ability of cardiopulmonary exercise testing to screen for underlying exercise-induced pulmonary hypertension (EIPH) in symptomatic patients who had a negative stress test and elevated right ventricular systolic pressure on echocardiogram. We also evaluated long-acting nitrates and ranolazine as medication challenges.

SETTING

Performed at a single, tertiary-care medical center in the United States.

PARTICIPANTS

Based on the inclusion and exclusion criteria, 81 patients were included in this study. The primary outcome of the study was to measure mean pulmonary arterial pressure at rest and exertion, as well as Wasserman curves. We also recorded patient demographics and risk factors, left ventricular ejection fraction, and mean oxygen consumption. Additionally, patients were monitored symptomatically after receiving long-acting nitrates and ranolazine.

RESULTS

A total of 61 patients had resting pulmonary arterial hypertension, and 27 had EIPH. The EIPH group had a significantly higher mean age of 71.67 years. Wasserman curves calculated from the cardiopulmonary exercise testing data revealed 3 subgroups of EIPH patients: cardiac restriction, chronotropic incompetence, and combination of both patterns. The EIPH group showed significant improvement in symptoms after receiving long-acting nitrate therapy.

CONCLUSIONS

Many patients with symptoms of angina, dyspnea, and/or fatigue on exertion with negative cardiac stress testing may have underlying pulmonary arterial hypertension, including EIPH. Therefore, these patients require adequate treatment and follow-up to prevent worsening of symptoms and pathology.

How does severe functional mitral regurgitation redefined by European guidelines affect pulmonary vascular resistance and hemodynamics in heart transplant candidates?

OBJECTIVE

Increased pulmonary artery pressure (PAP) and pulmonary vascular resistance (PVR) are important prognostic factors in patients with heart transplantation (HT). It is well known that severe mitral regurgitation increases pulmonary pressures. However, the European Society of Cardiology and the 6th World Symposium of pulmonary hypertension (PH) task force redefined severe functional mitral regurgitation (FMR) and PH, respectively. We aimed to investigate the effect of severe FMR on PAP and PVR based on these major redefinitions in patients with HT.

METHODS

A total of 212 patients with HT were divided into 2 groups: those with severe FMR (n=70) and without severe FMR (n=142). Severe FMR was defined as effective orifice regurgitation area ≥20 mm2 and regurgitation volume ≥30 mL where the mitral valve was morphologically normal. A mean PAP of >20 mm Hg was accepted as PH. Patients with left ventricular ejection fraction ≤25% were included in the study.

RESULTS

The systolic PAP, mean PAP, and PVR were higher in patients with severe FMR than in those without severe FMR [58.5 (48.0-70.2) versus 45.0 (36.0-64.0), p<0.001; 38.0 (30.2-46.6) versus 31.0 (23.0-39.5), p=0.004; 4.0 (2.3-6.8) versus 2.6 (1.2-4.3), p=0.001, respectively]. Univariate analysis revealed that the severe FMR is a risk factor for PVR ≥3 and 5 WU [odds ratio (OR): 2.0, 95% confidence interval (CI): 1.1-3.6, p=0.009; and OR: 3.2, 95% CI: 1.5-6.7, p=0.002]. The multivariate regression analysis results revealed that presence of severe FMR is an independent risk factor for PVR ≥3 WU and presence of combined pre-post-capillary PH (OR: 2.23, 95% CI: 1.30-3.82, p=0.003 and OR: 2.30, 95% CI: 1.25-4.26, p=0.008).

CONCLUSION

Even in the updated definition of FMR with a lower threshold, severe FMR is associated with higher PVR, systolic PAP, and mean PAP and appears to have an unfavorable effect on pulmonary hemodynamics in patients with HT.

Transition from Bosentan to Ambrisentan in Pulmonary Arterial Hypertension: A Single-Center Prospective Study

Background

Pulmonary hypertension patients experienced a high financial burden due to the high cost of drug therapy, high incidence of comorbidities and hospitalizations. Endothelin receptor antagonists (ERAs) in PAH treatment showed a high cost. While ambrisentan has been covered by medical insurance of a local government of China, there has been a drug transition from bosentan to ambrisentan in treating PAH patients. We evaluated the safety, efficacy and tolerability of ambrisentan after drug transition.

Methods

Liver and renal functions were inspected at baseline, month 1, 3 and 6. NT-proBNP, echocardiographic variables, WHO functional class (WHO-FC), 6-minute walking distance (6MWD) were measured in the baseline and month 6 to evaluate the safety and efficacy. Quality of life (QOL) scale was used in the baseline and month 6 to investigate the tolerability and quality of life of PAH patients.

Results

Among 224 PAH patients, 49 stable PAH patients meet the inclusion criteria were enrolled, among which three patients discontinued during the study. Our results showed no difference in 6-minute walking distance (6MWD) of PAH patients from baseline and month 6. The liver and renal function, N-terminal pro-brain natriuretic peptide (NT-proBNP), WHO functional class (WHO-FC) showed no difference either. For echocardiography parameters, the left ventricular end-diastolic dimension (LVEDD) of month 6 decreased. Other parameters were no significant difference from the baseline. There was no difference in the QOL scale between baseline and month 6.

Conclusion

Our results suggested that it is safe and tolerable for stable PAH patients to transition from bosentan to ambrisentan without influencing hematologic parameters or heart function.

Novel TNIP2 and TRAF2 Variants Are Implicated in the Pathogenesis of Pulmonary Arterial Hypertension

Background: Pulmonary arterial hypertension (PAH) is a rare disease characterized by pulmonary vascular remodeling and right heart failure. Specific genetic variants increase the incidence of PAH in carriers with a family history of PAH, those who suffer from certain medical conditions, and even those with no apparent risk factors. Inflammation and immune dysregulation are related to vascular remodeling in PAH, but whether genetic susceptibility modifies the PAH immune response is unclear. TNIP2 and TRAF2 encode for immunomodulatory proteins that regulate NF-κB activation, a transcription factor complex associated with inflammation and vascular remodeling in PAH. Methods: Two unrelated families with PAH cases underwent whole-exome sequencing (WES). A custom pipeline for variant prioritization was carried out to obtain candidate variants. To determine the impact of TNIP2 and TRAF2 in cell proliferation, we performed an MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] assay on healthy lung pericytes transfected with siRNA specific for each gene. To measure the effect of loss of TNIP2 and TRAF2 on NF-kappa-beta (NF-κB) activity, we measured levels of Phospho-p65-NF-κB in siRNA-transfected pericytes using western immunoblotting. Results: We discovered a novel missense variant in the TNIP2 gene in two affected individuals from the same family. The two patients had a complex form of PAH with interatrial communication and scleroderma. In the second family, WES of the proband with PAH and primary biliary cirrhosis revealed a de novo protein-truncating variant in the TRAF2. The knockdown of TNIP2 and TRAF2 increased NF-κB activity in healthy lung pericytes, which correlated with a significant increase in proliferation over 24 h. Conclusions: We have identified two rare novel variants in TNIP2 and TRAF2 using WES. We speculate that loss of function in these genes promotes pulmonary vascular remodeling by allowing overactivation of the NF-κB signaling activity. Our findings support a role for WES in helping identify novel genetic variants associated with dysfunctional immune response in PAH.

Pulmonary Hypertension in Association with Lung Disease: Quantitative CT and Artificial Intelligence to the Rescue? State-of-the-Art Review

Accurate phenotyping of patients with pulmonary hypertension (PH) is an integral part of informing disease classification, treatment, and prognosis. The impact of lung disease on PH outcomes and response to treatment remains a challenging area with limited progress. Imaging with computed tomography (CT) plays an important role in patients with suspected PH when assessing for parenchymal lung disease, however, current assessments are limited by their semi-qualitative nature. Quantitative chest-CT (QCT) allows numerical quantification of lung parenchymal disease beyond subjective visual assessment. This has facilitated advances in radiological assessment and clinical correlation of a range of lung diseases including emphysema, interstitial lung disease, and coronavirus disease 2019 (COVID-19). Artificial Intelligence approaches have the potential to facilitate rapid quantitative assessments. Benefits of cross-sectional imaging include ease and speed of scan acquisition, repeatability and the potential for novel insights beyond visual assessment alone. Potential clinical benefits include improved phenotyping and prediction of treatment response and survival. Artificial intelligence approaches also have the potential to aid more focused study of pulmonary arterial hypertension (PAH) therapies by identifying more homogeneous subgroups of patients with lung disease. This state-of-the-art review summarizes recent QCT developments and potential applications in patients with PH with a focus on lung disease.

Identifying Potential Mutations Responsible for Cases of Pulmonary Arterial Hypertension

Pulmonary Arterial Hypertension (PAH) is a progressive and devastating disease for which there is an escalating body of genetic and related pathophysiological information on disease pathobiology. Nevertheless, the success to date in identifying susceptibility genes, genetic variants and epigenetic processes has been limited due to PAH clinical multi-faceted variations. A number of germline gene candidates have been proposed but demonstrating consistently the association with PAH has been problematic, at least partly due to the reduced penetrance and variable expressivity. Although the data for bone morphogenetic protein receptor type 2 (BMPR2) and related genes remains undoubtedly the most extensive, recent advanced gene sequencing technologies have facilitated the discovery of further gene candidates with mutations among those with and without familial forms of PAH. An in depth understanding of the multitude of biologic variations associated with PAH may provide novel opportunities for therapeutic intervention in the coming years. This knowledge will irrevocably provide the opportunity for improved patient and family counseling as well as improved PAH diagnosis, risk assessment, and personalized treatment.

Molecular and Genetic Profiling for Precision Medicines in Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a rare and chronic lung disease characterized by progressive occlusion of the small pulmonary arteries, which is associated with structural and functional alteration of the smooth muscle cells and endothelial cells within the pulmonary vasculature. Excessive vascular remodeling is, in part, responsible for high pulmonary vascular resistance and the mean pulmonary arterial pressure, increasing the transpulmonary gradient and the right ventricular “pressure overload”, which may result in right ventricular (RV) dysfunction and failure. Current technological advances in multi-omics approaches, high-throughput sequencing, and computational methods have provided valuable tools in molecular profiling and led to the identification of numerous genetic variants in PAH patients. In this review, we summarized the pathogenesis, classification, and current treatments of the PAH disease. Additionally, we outlined the latest next-generation sequencing technologies and the consequences of common genetic variants underlying PAH susceptibility and disease progression. Finally, we discuss the importance of molecular genetic testing for precision medicine in PAH and the future of genomic medicines, including gene-editing technologies and gene therapies, as emerging alternative approaches to overcome genetic disorders in PAH.

Curable Syncope in Primary Pulmonary Hypertension with Novel Atrial Flow Regulator

Pulmonary artery hypertension (PAH) occurs when mean pulmonary artery pressure (PAP) is higher than 25 mmHg in rest or 30 mmHg during activity. Idiopathic pulmonary artery hypertension (IPAH) is defined as PAH without a definite reason. The IPAH is a rare disease with a high mortality rate if left untreated. To date, there has been no definite cure for this entity, and most treatments are for symptom relief or improvement in the quality of life. For many years, decompressing the right heart through a hole in the interatrial septum has been advised to alleviate some of their symptoms, specifically syncope. Atrial flow regulator (AFR) is a device to make an iatrogenic interatrial hole and finally a unidirectional shunt. It has been used for some PAH patients for symptom relief. Herein, we report a 36-year-old female case with diagnosed IPAH for 6 years. In the last 3 years, the case had frequent syncope with shortening intervals. The AFR was implanted for her without any complications. Then, within 6 months of follow-up, she had only one syncope episode. A significant change was observed in her 6-minute walk and PAP.

The Growing Role of Echocardiography in Pulmonary Arterial Hypertension Risk Stratification: The Missing Piece

Pulmonary arterial hypertension (PAH) is a rare, progressive disease with a poor prognosis. The pathophysiologic model is mainly characterized by an afterload mismatch in which an increased right ventricle afterload, driven by increased pulmonary vascular resistance (PVR), leads to right heart failure. International guidelines recommend optimization of treatment based on regular risk assessments to achieve or maintain a low-risk status. Current risk scores are based on a multi-modality approach, including demographic, clinical, functional, exercise, laboratory, and hemodynamic parameters, which lack significant echocardiographic parameters. The originality of echocardiography relies on the opportunity to assess in a non-invasive way a physiologically meaningful combination of easy to measure variables tightly related to right ventricle adaptation/maladaptation to increased afterload, the main determinant of a patient's prognosis. Echo-derived morphological and functional parameters have been investigated in PAH, proving to have prognostic relevance. Different therapeutic strategies proved to have different effects in reducing PVR. An upfront combination of drugs, including a parenteral prostacyclin, has shown to be associated with right heart reverse remodeling in a greater proportion of patients than other treatment strategies as a function of PVR reduction. Adding echocardiographic data to current risk scores would allow better identification of right ventricle (RV) adaptation in PAH patients' follow-up. This additional information would allow better stratification of the patient, leading to optimized and personalized therapeutic management.

Targeting Jak-Stat Signaling in Experimental Pulmonary Hypertension

In pulmonary arterial hypertension (PAH), progressive structural remodeling accounts for the pulmonary vasculopathy including the obliteration of the lung vasculature that causes an increase in vascular resistance and mean blood pressure in the pulmonary arteries ultimately leading to right heart failure-mediated death. Deciphering the molecular details of aberrant signaling of pulmonary vascular cells in PAH is fundamental for the development of new therapeutic strategies. We aimed to identify kinases as new potential drug targets that are dysregulated in PAH by means of a peptide-based kinase activity assay. We performed a tyrosine kinase-dependent phosphorylation assay using 144 selected microarrayed substrate peptides. The differential signature of phosphopeptides was used to predict alterations in tyrosine kinase activities in human pulmonary arterial smooth muscle cells (HPASMCs) from patients with idiopathic PAH (IPAH) compared with healthy control cells. Thereby, we observed an overactivation and an increased expression of Jak2 (Janus kinase 2) in HPASMCs from patients with IPAH as compared with controls. In vitro, IL-6-induced proliferation and migration of HPASMCs from healthy individuals as well as from patients with IPAH were reduced in a dose-dependent manner by the U.S. Food and Drug Administration-approved Jak1 and Jak2 inhibitor ruxolitinib. In vivo, ruxolitinib therapy in two experimental models of pulmonary arterial hypertension dose-dependently attenuated the elevation in pulmonary arterial pressure, partially reduced right ventricular hypertrophy, and almost completely restored cardiac index without signs of adverse events on cardiac function. Therefore, we propose that ruxolitinib may present a novel therapeutic option for patients with PAH by reducing pulmonary vascular remodeling through effectively blocking Jak2-Stat3 (signal transducer of activators of transcription)-mediated signaling pathways.

The Evolution in Nomenclature, Diagnosis, and Classification of Pulmonary Hypertension

The current description of pulmonary hypertension is a testament to the physicians and scientists who dedicated their lives to furthering understanding of the pulmonary circulation. This has spanned a millennium, from ancient Egyptian descriptions of human anatomy to the current molecular and hemodynamic phenotyping of pulmonary hypertension. The recent Sixth World Symposium on Pulmonary Hypertension is a direct result of these discoveries and reflects an evolution in a classification scheme that has spanned half a century. This provides a framework for future directions related to therapeutics and mechanisms of disease.

The Prevalence of Pulmonary Hypertension Among Maintenance Dialysis Patients With ESRD and Its Associated Factors: A Retrospective Study

Aim: To determine the prevalence of pulmonary hypertension (PH) and its associated factors among end-stage renal disease (ESRD) patients who underwent maintenance dialysis. Methods: A total of 491 patients received echocardiography examinations and underwent pulmonary artery systolic pressure (PASP) assessments. A subgroup of 283 patients were subjected to plasma creatinine (Cr) and blood urea nitrogen concentration (BUN) tests, routine blood examinations and electrolyte analysis. First, we compared the differences in echocardiographic, Cr and BUN, blood routine and electrolyte parameters between PH and non-PH groups. The correlations between PASP and the parameters mentioned above were also analyzed. Furthermore, univariate and adjusted logistic regression analyses were performed to identify the independent associated factors. Results: The incidence of PH among ESRD patients who were treated with maintenance dialysis was 34.6%. Most of the echocardiographic parameters, including end-diastolic internal diameters of the left atrium, left ventricle, right atrium, and pulmonary artery, as well as interventricular septum mobility, left ventricular posterior wall mobility, fractional shortening, stroke volume and left ventricle ejection fraction (LVEF), were associated with PH. Furthermore, Mg²⁺ (p = 0.037) and Cl^- (p = 0.043) were significantly associated with PASP. However, after adjustments were made in the regression analysis, only internal diameters of the left atrium, right atrium, and LVEF were independently associated with PH. Conclusion: PH is prevalent, with a relatively high incidence among ESRD patients who undergo maintenance dialysis. The sizes of the left and right atria as well as LVEF were independently associated with PH, but further cohort and basic mechanistic studies are needed to confirm this finding.

Pulmonary hypertension associated with congenital heart disease; clinical decision scenario

Pulmonary arterial hypertension associated with congenital heart disease (PAH-CHD) is one type under group 1 PH. Undiagnosed or delayed diagnosis of significant CHD might lead to significant PAH and at the end might lead to Eisenmenger syndrome. We could expect the degree of PAH in patients with CHD by proper clinical assessment as well as by the basic assessment tools including the chest x-ray (CXR), ECG, and transthoracic echocardiography (TTE). We are presenting a three and half years old child with a delayed/missed diagnosis of large patent ductus arteries (PDA) who present with significant PAH. Clinical evaluation, CXR, ECG, TTE, as well as cardiac catheterization data are presented, with a review of the current guidelines regarding the management of pediatric patients with PAH-CHD.

High prevalence of salivary gland ultrasound abnormalities in systemic sclerosis

OBJECTIVE

To evaluate salivary gland (SG) involvement in patients with systemic sclerosis (SSc) using SG ultrasound (SGUS).

METHODS

Patients with SSc (n=62), primary Sjögren's syndrome (pSS) (n=59), and idiopathic Sicca syndrome (n=43) were evaluated using the outcome measures in rheumatology clinical trial (OMERACT) definitions of the SGUS scoring system. The hyperechogenic bands using the 0-3 scoring system, intraglandular power Doppler signal (PDS), and SG volumes were also assessed.

RESULTS

The proportion of patients with OMERACT grades (≥2) among the four SGs was significantly higher in SSc (51.6%) and pSS (62.7%) groups than those in the idiopathic Sicca syndrome group (4.7%). Patients with SSc and pSS had significantly higher total fibrosis grades than controls. No difference in fibrosis grades was observed between SSc and pSS groups. The PDS scores of SGs were higher in the SSc group than in the idiopathic Sicca syndrome group. SG volumes did not differ between the groups. SSc patients with SGUS grades ≥2 had more anti-centromere antibodies (ACA) (65.6% vs. 30.0%) than individuals with grades 0-1. SSc patients with fibrosis grades ≥2 reported more Sicca symptoms than those with grades 0-1. Inhomogeneity and hyperechogenic bands within the SGs were not associated with organ involvement in SSc.

CONCLUSIONS

More than half of patients with SSc, specifically with ACA, showed SG involvement. SG fibrosis was more prominent in SSc than in idiopathic Sicca syndrome and was associated with subjective Sicca symptoms. However, hyperechoic bands within the SGs are not features that can differentiate between SSc and pSS.

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.

Current Understanding of Circulating Biomarkers in Pulmonary Hypertension Due to Left Heart Disease

Pulmonary hypertension due to left heart disease (PH-LHD; Group 2), especially in the setting of heart failure with preserved ejection fraction (HFpEF), is the most frequent cause of PH. Despite its prevalence, no effective therapies for PH-LHD are available at present. This is largely due to the lack of a concise definition for hemodynamic phenotyping, existence of significant gaps in the understanding of the underlying pathology and the impact of associated comorbidities, as well as the absence of specific biomarkers that can aid in the early diagnosis and management of this challenging syndrome. Currently, B-type natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP) are guideline-recommended biomarkers for the diagnosis and prognosis of heart failure (HF) and PH. Endothelin-1 (ET-1), vascular endothelial growth factor-D (VEGF-D), and microRNA-206 have also been recently identified as new potential circulating biomarkers for patients with PH-LHD. In this review, we aim to present the current state of knowledge of circulating biomarkers that can be used to guide future research toward diagnosis, refine specific patient phenotype, and develop therapeutic approaches for PH-LHD, with a particular focus on PH-HFpEF. Potential circulating biomarkers identified in pre-clinical models of PH-LHD are also summarized here.

Left ventricular dysfunction in heart failure with preserved ejection fraction-molecular mechanisms and impact on right ventricular function

The current classification of heart failure (HF) based on left ventricular (LV) ejection fraction (EF) identifies a large group of patients with preserved ejection fraction (HFpEF) with significant morbidity and mortality but without prognostic benefit from current HF therapy. Co-morbidities and conditions such as arterial hypertension, diabetes mellitus, chronic kidney disease, adiposity and aging shape the clinical phenotype and contribute to mortality. LV diastolic dysfunction and LV structural remodeling are hallmarks of HFpEF, and are linked to remodeling of the cardiomyocyte and extracellular matrix. Pulmonary hypertension (PH) and right ventricular dysfunction (RVD) are particularly common in HFpEF, and mortality is up to 10-fold higher in HFpEF patients with vs. without RV dysfunction. Here, we review alterations in cardiomyocyte function (i.e., ion homeostasis, sarcomere function and cellular metabolism) associated with diastolic dysfunction and summarize the main underlying cellular pathways. The contribution and interaction of systemic and regional upstream signaling such as chronic inflammation, neurohumoral activation, and NO-cGMP-related pathways are outlined in detail, and their diagnostic and therapeutic potential is discussed in the context of preclinical and clinical studies. In addition, we summarize prevalence and pathomechanisms of RV dysfunction in the context of HFpEF and discuss mechanisms connecting LV and RV dysfunction in HFpEF. Dissecting the molecular mechanisms of LV and RV dysfunction in HFpEF may provide a basis for an improved classification of HFpEF and for therapeutic approaches tailored to the molecular phenotype.

Current and emerging therapeutic approaches to pulmonary hypertension

Pulmonary arterial hypertension (PAH) is a progressive and fatal lung disease of multifactorial etiology. Most of the available drugs and FDA-approved therapies for treating pulmonary hypertension attempt to overcome the imbalance between vasoactive and vasodilator mediators, and restore the endothelial cell function. Traditional medications for treating PAH include the prostacyclin analogs and receptor agonists, phosphodiesterase 5 inhibitors, endothelin-receptor antagonists, and cGMP activators. While the current FDA-approved drugs showed improvements in quality of life and hemodynamic parameters, they have shown only very limited beneficial effects on survival and disease progression. None of them offers a cure against PAH, and the median survival rate remains less than three years from diagnosis. Extensive research efforts have led to the emergence of innovative therapeutic approaches in the area of PAH. In this review, we provide an overview of the current FDA-approved therapies in PAH and discuss the associated clinical trials and reported-side effects. As recent studies have led to the emergence of innovative therapeutic approaches in the area of PAH, we also focus on the latest promising therapies in preclinical studies such as stem cell-based therapies, gene transfer, and epigenetic therapies.

The Role and Regulation of Pulmonary Artery Smooth Muscle Cells in Pulmonary Hypertension

Pulmonary hypertension (PH) is one of the most devastating cardiovascular diseases worldwide and it draws much attention from numerous scientists. As an indispensable part of pulmonary artery, smooth muscle cells are worthy of being carefully investigated. To elucidate the pathogenesis of PH, several theories focusing on pulmonary artery smooth muscle cells (PASMC), such as hyperproliferation, resistance to apoptosis, and cancer theory, have been proposed and widely studied. Here, we tried to summarize the studies, concentrating on the role of PASMC in the development of PH, feasible molecular basis to intervene, and potential treatment to PH.

Beyond the genome: challenges and potential for epigenetics-driven therapeutic approaches in pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a devastating disease of the cardiopulmonary system caused by the narrowing of the pulmonary arteries, leading to increased vascular resistance and pressure. This leads to right ventricle remodeling, dysfunction, and eventually, death. While conventional therapies have largely focused on targeting vasodilation, other pathological features of PAH including aberrant inflammation, mitochondrial dynamics, cell proliferation, and migration have not been well explored. Thus, despite some recent improvements in PAH treatment, the life expectancy and quality of life for patients with PAH remains poor. Showing many similarities to cancers, PAH is characterized by increased pulmonary arterial smooth muscle cell proliferation, decreased apoptotic signaling pathways, and changes in metabolism. The recent successes of therapies targeting epigenetic modifiers for the treatment of cancer has prompted epigenetic research in PAH, revealing many new potential therapeutic targets. In this minireview we discuss the emergence of epigenetic dysregulation in PAH and highlight epigenetic-targeting compounds that may be effective for the treatment of PAH.

Clinical characteristics and survival of Chinese patients diagnosed with pulmonary arterial hypertension who carry BMPR2 or EIF2KAK4 variants

Background

Variants in the gene encoding bone morphogenetic protein receptor type II (BMPR2) are the most common genetic cause of pulmonary arterial hypertension (PAH), whereas biallelic variants in the eukaryotic translation initiation factor 2 alpha kinase 4 gene (EIF2AK4) are described in pulmonary veno-occlusive disease/pulmonary capillary haemangiomatosis (PVOD/PCH). Racial background may influence the clinical characteristics of patients diagnosed with PAH or PVOD/PCH. Here, we compared the clinical characteristics and survival between patients with BMPR2 variants or EIF2AK4 variants in a Chinese population.

Methods

Heterozygous variants in BMPR2 and homozygous or compound heterozygous biallelic EIF2AK4 variants predicted to be deleterious were identified as potentially causal. Clinical and radiological data were collected and analysed. The primary outcomes were death or lung transplantation. Hazard ratios (HRs) for death or transplantation associated with the presence of BMPR2 or biallelic EIF2AK4 variants were calculated using Cox proportional hazards models to analyse patient survival.

Results

Two hundred thirty-two patients with PAH were enrolled for genetic testing, and PAH patients with associated conditions were excluded from the study. Forty-five patients with BMPR2 variants and 11 patients with biallelic EIF2AK4 variants were recruited. PAH patients with BMPR2 or biallelic EIF2AK4 variants presented symptoms at the ages of 25.57 ± 10.17 years and 31.6 ± 9.38 years, respectively. The whole group of patients showed female dominance either with BMPR2 variants or biallelic EIF2AK4 variants. Specific radiological abnormalities are more prominent in EIF2AK4 variant carriers but can also be found in some patients with BMPR2 variants. Biallelic EIF2AK4 variant carriers had worse survival than BMPR2 variant carriers (p < 0.0001).

Conclusions

Clinical pictures of PAH patients with BMPR2 and biallelic EIF2AK4 variants in the Chinese population differ from other populations by a younger age at diagnosis and demonstrate female dominance in the whole patient group. High-resolution chest CT can help assist in differentiating PAH with PVOD/PCH. BMPR2 variants and biallelic EIF2AK4 variants are associated with adverse outcomes, but the survival of patients with biallelic EIF2AK4 variants is dismal.

Management of reproductive health in patients with pulmonary hypertension

Pulmonary hypertension is characterized by elevated pulmonary artery pressure caused by several clinical conditions that affect pulmonary vasculature. Morbidity and death in this condition are related to the development of right ventricular failure. Normal physiologic changes that occur in pregnancy to support the growing fetus can pose hemodynamic challenges to the pregnant patient with pulmonary hypertension that results in increased morbidity and mortality rates. Current guidelines recommend that patients with known pulmonary hypertension be counseled against pregnancy. This review aims to provide clinicians with guidelines for preconception counseling, medication management, and delivery planning.

Efficacy and safety of tetramethylpyrazine phosphate on pulmonary hypertension: study protocol for a randomized controlled study

BACKGROUND

Tetramethylpyrazine (TMP), an active ingredient in the traditional Chinese herbal medicine Rhizoma Chuanxiong, has been used clinically for the prevention and treatment of cardiovascular disease. The benefits of TMP are largely attributed to its anti-oxidative and vasodilative properties. However, the efficacy of TMP in the treatment of pulmonary hypertension (PH) is unknown. We hypothesized that TMP may have a therapeutic effect in patients with PH.

METHODS/DESIGN

A randomized, single-blinded, clinical study with a TMP treatment group and a control group will be conducted to evaluate the efficacy and safety of TMP intervention in patients with PH. The recruitment target is 120 subjects meeting the following criteria: (i) at rest and at sea level, mean pulmonary artery pressure above 20 mmHg and pulmonary capillary wedge pressure below 15 mmHg; (ii) type 1 or 4 PH in the stable phase; (iii) age 15-70 years; (iv) 6-min walk distance between 100 and 450 m; (v) World Health Organization (WHO) functional classification of pulmonary hypertension of II, III, or IV. Subjects will be assigned randomly into two groups at a ratio of 1:2 (control:TMP). Both groups will receive routine treatment, and the treatment group will also receive oral TMP (100 mg) three times a day for 16 weeks. All patients will be followed up for 4, 8, 12, and 16 weeks; symptoms and patient compliance will be recorded.

DISCUSSION

We aimed to determine the efficacy and safety of TMP for the treatment of PH.

TRIAL REGISTRATION

Chinese Clinical Trial Register, ChiCTR1800018664. Registered on 2 October 2018.