Clinical update on pulmonary hypertension

Pharmacological Gq inhibition induces strong pulmonary vasorelaxation and reverses pulmonary hypertension

Pulmonary arterial hypertension (PAH) is a life-threatening disease with limited survival. Herein, we propose the pharmacological inhibition of Gq proteins as a novel concept to counteract pulmonary vasoconstriction and proliferation/migration of pulmonary artery smooth muscle cells (PASMCs) in PAH. We demonstrate that the specific pan-Gq inhibitor FR900359 (FR) induced a strong vasorelaxation in large and small pulmonary arteries in mouse, pig, and human subjects ex vivo. Vasorelaxation by FR proved at least as potent as the currently used triple therapy. We also provide in vivo evidence that local pulmonary application of FR prevented right ventricular systolic pressure increase in healthy mice as well as in mice suffering from hypoxia (Hx)-induced pulmonary hypertension (PH). In addition, we demonstrate that chronic application of FR prevented and also reversed Sugen (Su)Hx-induced PH in mice. We also demonstrate that Gq inhibition reduces proliferation and migration of PASMCs in vitro. Thus, our work illustrates a dominant role of Gq proteins for pulmonary vasoconstriction as well as remodeling and proposes direct Gq inhibition as a powerful pharmacological strategy in PH.

Understanding pulmonary hypertension: the need for an integrative metabolomics and transcriptomics approach

Pulmonary hypertension (PH), characterised by mean pulmonary arterial pressure (mPAP) >20 mm Hg at rest, is a complex pathophysiological disorder associated with multiple clinical conditions. The high prevalence of the disease along with increased mortality and morbidity makes it a global health burden. Despite major advances in understanding the disease pathophysiology, much of the underlying complex molecular mechanism remains to be elucidated. Lack of a robust diagnostic test and specific therapeutic targets also poses major challenges. This review provides a comprehensive update on the dysregulated pathways and promising candidate markers identified in PH patients using the transcriptomics and metabolomics approach. The review also highlights the need of using an integrative multi-omics approach for obtaining insight into the disease at a molecular level. The integrative multi-omics/pan-omics approach envisaged to help in bridging the gap from genotype to phenotype is outlined. Finally, the challenges commonly encountered while conducting omics-driven studies are also discussed.

Liver injury due to endothelin receptor antagonists: a real-world study based on post-marketing drug monitoring data

BACKGROUND

Liver injury is the hallmark adverse reaction of endothelin receptor antagonist (ERA). Since the first drug, bosentan has been widely used in clinical practice, hepatotoxicity has been accompanied by the history of ERA. The new ERA has been proven to have a lower liver risk but the current research findings are inconsistent. ERA-based targeted drug combinations are commonly used in the treatment of pulmonary arterial hypertension, where the risk of liver injury is difficult to estimate.

OBJECTIVES

This study aimed to compare the correlation between ERA and different ERA combination regimens with liver injury in the real world.

DESIGN

This is a retrospective study using data from the Adverse Event Reporting System (Food and Drug Administration AERS, FAERS).

METHODS

The study used proportional imbalance and Bayesian analysis to mine FAERS data from January 2004 to December 2022 to determine the association of three ERAs with liver injury and to further mine the risk of liver injury due to the combination of ERAs with other targeted drugs. In addition, we analyzed the onset time, mortality, and hospitalization rate of liver injury caused by different ERA combination regimens.

RESULTS

We screened out 3581 ERA-related liver injury events, of which bosentan (59.82%) had the largest number of cases. The patients with liver injury were mainly female (60.63%), and the age was concentrated between 61 and 75 years (26.75%). According to different signal mining methods, reporting odds ratio (ROR; 3.38, 95% confidence interval = 3.23-3.53), proportional reporting ratio (PRR; 3.22, χ2 = 37.84), Bayesian confidence propagation neural network (BCPNN; 1.68, 95% confidence interval = 1.61), multi-item gamma Poisson shrinker (MGPS; 3.21, 95% confidence interval = 3.09), bosentan had the strongest association with liver injury compared to ambrisentan and macitentan. Furthermore, bosentan + sildenafil [ROR (2.52, 95% confidence interval = 2.23-2.84), PRR (2.44, χ2 = 15.92), BCPNN (1.29, 95% confidence interval = 1.14), MGPS (2.44, 95% confidence interval = 2.21)], bosentan + epoprostenol [ROR (5.39, 95% confidence interval = 4.29-6.77), PRR (4.94, χ2 = 65.18), BCPNN (2.30, 95% confidence interval = 1.83), MGPS (4.94, 95% confidence interval = 4.08)], bosentan + iloprost [ROR (2.70, 95% confidence interval = 2.11-3.45), PRR (2.61, χ2 = 31.03), BCPNN (1.38, 95% confidence interval = 1.08), MGPS (2.61, 95% confidence interval = 2.12)] had a higher risk of liver injury caused by the three ERA combination regimens. The median time to onset of hepatotoxicity associated with all ERA combination regimens was 259 days (interquartile range: 58-716.5 days). Finally, the hospitalization rate for patients experiencing hepatotoxicity with ERA combination regimens was 47.86% and the mortality rate was 12.67%.

CONCLUSION

By mining the FAERS, we analyzed and compared the risk of liver injury related to different ERA and ERA combination regimens, and the onset time and adverse reaction outcomes of all ERA combination regimens. According to the results of the study, bosentan had the highest risk of liver injury and the combination regimens bosentan + sildenafil, bosentan + epoprostenol, and bosentan + iloprost had a stronger risk of liver injury. From the early stages of treatment, we need to regularly monitor the liver function of patients, especially for females and the elderly, and discontinue the suspected drug as soon as the liver injury occurs.

Development of novel bosentan analogues as endothelin receptor antagonists for pulmonary arterial hypertension

Since decades, bosentan has been in use for the treatment of pulmonary arterial hypertension (PAH). However, chronic exposure to bosentan leads to the development of resistance, tolerance, and serious adverse effects that have restricted its usage in clinical practices. To surmount these limitations, some new bosentan derivatives have been synthesized and evaluated for their therapeutic efficacy in PAH. Molecular docking analyses of all the synthesized derivatives were carried out using the endothelin (ET) receptor. In addition, the inhibitory ability of synthesized derivatives was determined in in vitro assay employing an ET-1 human ELISA kit. Among the synthesized derivatives, three derivatives namely 17d, 16j, and 16h with higher docking scores and lower IC50 values were selected for determination of the magnitude of the binding force between the derivative and ET receptor using molecular dynamics (MD) simulations study. Further, these derivatives were subjected to in vivo studies using monocrotaline (MCT) induced PAH in rat model. Results of in vivo studies inferred that the derivatives exhibit impressive ability to reduce PAH. Besides, its protective role was also evidenced in hemodynamic and right ventricular hypertrophy analyses, histological analysis, cardiac biomarkers, hypoxia-inducible factor 1 alpha (HIF1α) levels, and biochemical studies. Furthermore, gene quantification by quantitative RT-PCR and Western blot analysis was also performed to examine its effect on the expression of key proteins in PAH. Notably, amongst three, derivative 16h exhibited the most encouraging results in molecular docking analysis, in vitro, in vivo, histopathological, biochemical, protein expression, and MD studies. Besides, derivative 16h also showed impressive pharmacokinetic features in ADMET analysis. In conclusion, derivative 16 h could act as a reliable ET receptor antagonist and requires further exploration to attain its therapeutic utility in PAH management.

Burden of pulmonary hypertension due to chronic obstructive pulmonary disease: Analysis of exacerbations and healthcare resource utilization in the United States

BACKGROUND

The burden of pulmonary hypertension (PH) among patients with chronic obstructive pulmonary disease (COPD) is not well understood. The present retrospective cohort study aimed to quantify the clinical and economic burden of PH in patients with COPD.

METHODS

Adults with COPD were retrospectively identified in the Optum® Clinformatics® Data Mart between July 1, 2016 and June 30, 2021. Those diagnosed with PH were assigned to the PH-COPD cohort and those without a diagnosis of PH were assigned to the COPD cohort. Outcomes, including the number of visits for exacerbations and all-cause and COPD-related healthcare resource utilization (HCRU) and costs per patient per month (PPPM), were compared between cohorts. Baseline and study outcomes were analyzed descriptively. For significance testing, continuous variables were analyzed using Student's t-tests and categorical variables were analyzed using Chi-square tests.

RESULTS

A total of 1627 patients with PH-COPD were matched 1:1 to COPD patients without PH. A greater percentage of PH-COPD patients experienced COPD exacerbations vs. the COPD cohort (p < 0.001) and the PH-COPD cohort had more total (p < 0.001) and severe exacerbation-related visits PPPM (p < 0.001). All-cause and COPD-related HCRU PPPM estimates were higher among the PH-COPD cohort vs. the COPD cohort (p < 0.01). Total all-cause (p < 0.001) and COPD-related costs (p < 0.001) were higher among PH-COPD patients than COPD patients.

CONCLUSIONS

Patients with PH-COPD had higher rates of severe exacerbations, hospitalizations, and costs compared to COPD patients without PH, underscoring the need for targeted therapies to prevent and manage PH in patients with COPD.

Role of pulmonary perfusion magnetic resonance imaging for the diagnosis of pulmonary hypertension: A review

Among five types of pulmonary hypertension, chronic thromboembolic pulmonary hypertension (CTEPH) is the only curable form, but prompt and accurate diagnosis can be challenging. Computed tomography and nuclear medicine-based techniques are standard imaging modalities to non-invasively diagnose CTEPH, however these are limited by radiation exposure, subjective qualitative bias, and lack of cardiac functional assessment. This review aims to assess the methodology, diagnostic accuracy of pulmonary perfusion imaging in the current literature and discuss its advantages, limitations and future research scope.

Unraveling the epigenetic landscape of pulmonary arterial hypertension: implications for personalized medicine development

Pulmonary arterial hypertension (PAH) is a multifactorial disease associated with the remodeling of pulmonary blood vessels. If left unaddressed, PAH can lead to right heart failure and even death. Multiple biological processes, such as smooth muscle proliferation, endothelial dysfunction, inflammation, and resistance to apoptosis, are associated with PAH. Increasing evidence suggests that epigenetic factors play an important role in PAH by regulating the chromatin structure and altering the expression of critical genes. For example, aberrant DNA methylation and histone modifications such as histone acetylation and methylation have been observed in patients with PAH and are linked to vascular remodeling and pulmonary vascular dysfunction. In this review article, we provide a comprehensive overview of the role of key epigenetic targets in PAH pathogenesis, including DNA methyltransferase (DNMT), ten-eleven translocation enzymes (TET), switch-independent 3A (SIN3A), enhancer of zeste homolog 2 (EZH2), histone deacetylase (HDAC), and bromodomain-containing protein 4 (BRD4). Finally, we discuss the potential of multi-omics integration to better understand the molecular signature and profile of PAH patients and how this approach can help identify personalized treatment approaches.

Protective effects of the Terminalia bellirica tannin-induced Nrf2/HO-1 signaling pathway in rats with high-altitude pulmonary hypertension

BACKGROUND

Oxidative stress and endothelial cell dysfunction induced by high-altitude hypoxia have important roles in the pathological process of high-altitude pulmonary hypertension (HAPH). Tannins present in Terminalia bellirica (Gaertn.) Roxb. (TTR) have pharmacological activities that produce oxidation resistance and exert anti-inflammatory effects. Whether TTR exerts a protective effect on HAPH remains unknown.

METHODS

A rat model of HAPH was established. The mean pulmonary arterial pressure (mPAP) of the animals was measured, the serum levels of SOD, MDA, and GSH-Px were measured using ELISA, and the expression of Bax, Bcl-2, Nrf2, and HO-1 proteins in the lung tissue of each group of rats was measured using Western blotting. Pathological changes in the lung tissue were also observed. A model of damage to H₂O₂-induced pulmonary artery endothelial cells (PAECs) was generated, and cell proliferation was measured using CCK-8 assays. Flow cytometry was used to measure ROS levels in PAECs. Western blotting was used to detect the expression of Bax, Bcl-2, Nrf2, and HO-1 proteins in PAECs.

RESULTS

The hemodynamic and pathologic findings showed that the mPAP of HAPH rats increased markedly, and the vascular wall thickness increased (P < 0.05). TTR reduced mPAP, alleviated or slowed pulmonary arterial remodeling, increased GSH-Px and SOD activity, lowered the level of MDA (P < 0.05), and downregulated the expression of Bax in the lung tissues of HAPH rats, while the expression of Bcl-2, Nrf2, and HO-1 was upregulated (P < 0.05). The results of the cell experiments showed that TTR inhibited H₂O₂-induced PAEC apoptosis and ROS production (P < 0.05), downregulated the expression of Bax in PAECs, and upregulated the expression of Bcl-2, Nrf2, and HO-1 (P < 0.05).

CONCLUSION

The results suggest that TTR reduces pulmonary arterial pressure, decreases oxidative stress during HAPH, and exerts protective effects in rats with HAPH and that its mechanism of action is related to regulation of the Nrf2/HO-1 signaling pathway.

ELABELA RELAXES RAT PULMONARY ARTERY AND TRACHEA VIA BKCa, KV, and KATP CHANNELS

OBJECTIVE

Elabela is a newly discovered peptide hormone. This study aimed to determine the functional effects and mechanisms of action of elabela in rat pulmonary artery and trachea.

MATERIALS AND METHODS

Vascular rings isolated from the pulmonary arteries of male Wistar Albino rats were placed in chambers in the isolated tissue bath system. The resting tension was set to 1g. After the equilibration period, the pulmonary artery rings were contracted with 10^-6M phenylephrine. Once a stable contraction was achieved, elabela was applied cumulatively (10^-10-10^-6M) to the vascular rings. To determine the vasoactive effect mechanisms of elabela, the specified experimental protocol was repeated after the incubation of signaling pathway inhibitors and potassium channel blockers. The effect and mechanisms of action of elabela on tracheal smooth muscle were also determined by a similar protocol.

RESULTS

Elabela exhibited a concentration-dependent relaxation in the precontracted rat pulmonary artery rings (p<.001). Maximal relaxation level was 83% (pEC₅₀: 7.947 CI95(7.824-8.069)). Removal of the endothelium, indomethacin incubation, and dideoxyadenosine incubation significantly decreased the vasorelaxant effect levels of elabela (p<.001). Elabela-induced vasorelaxation levels were significantly reduced after iberiotoxin, glyburide, and 4-Aminopyridine administrations (p<.001). L-NAME, methylene blue, apamin, TRAM-34, anandamide, and BaCl₂ administrations did not cause a significant change in the vasorelaxant effect level of elabela (p=1.000). Elabela showed a relaxing effect on precontracted tracheal rings (p<.001). Maximal relaxation level was 73% (pEC₅₀: 6.978 CI95(6.791-7.153)). The relaxant effect of elabela on tracheal smooth muscle was decreased significantly after indomethacin, dideoxyadenosine, iberiotoxin, glyburide, and 4-Aminopyridine incubations (p<.001).

CONCLUSIONS

Elabela exerted a prominent relaxant effect in the rat pulmonary artery and trachea. Intact endothelium, prostaglandins, cAMP signaling pathway, and potassium channels (BK_Ca, K_V, and K_ATP channels) are involved in the vasorelaxant effect of elabela. Prostaglandins, cAMP signaling pathway, BK_Ca channels, K_V channels, and K_ATP channels also contribute to elabela-induced tracheal smooth muscle relaxant effect.

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.

Association Between the Degree of Severity of Pulmonary Hypertension With the Presence of Pulmonary Artery Aneurysm: A Brief Updated Review for Clinicians

Pulmonary hypertension (PH) is defined as an increase in mean pulmonary arterial pressure (mPAP) ≥20 mm Hg at rest as assessed by right cardiac catheterization. It has a median survival nowadays of 6 years, compared to 2.8 years in the 1980s. A pulmonary artery aneurysm (PAA) is the focal dilation of a blood vessel involving all 3 layers of the vessel wall; they have a diameter greater than 4 cm measured in the trunk of the pulmonary artery. PAAs can be classified into proximal (or central) and peripheral. The clinical manifestations of PAA are primarily nonspecific, and most patients remain undiagnosed, even those with large PAA, due to its silent course; however, clinical manifestations occur unless when there are complications such as bronchial or tracheal compression (leading to cough and dyspnea), dissection, or rupture (leading to hemoptysis). PAH is observed in 66% of patients with PAA. PA dissections are usually associated with PAH; 80% of dissections occur in the main pulmonary trunk. Although there is no clear guideline for the best treatment of PAA, surgery is indicated in patients with a pulmonary trunk aneurysm >5.5 cm. It has been observed that patients in the PAH group associated with congenital heart disease tend to develop PAA more commonly. Those with PAH associated with connective tissue disease have a smaller diameter of PA dilation. This report presents a comprehensive review of PAA, discussing critical aspects of the clinical and imaging diagnosis, hemodynamics, and treatment. A comprehensive updated literature review is included; we believe this article will interest cardiopulmonologists.

Role of ryanodine receptor 2 and FK506-binding protein 12.6 dissociation in pulmonary hypertension

Pulmonary hypertension (PH) is a devastating disease characterized by a progressive increase in pulmonary arterial pressure leading to right ventricular failure and death. A major cellular response in this disease is the contraction of smooth muscle cells (SMCs) of the pulmonary vasculature. Cell contraction is determined by the increase in intracellular Ca2+ concentration ([Ca2+]i), which is generated and regulated by various ion channels. Several studies by us and others have shown that ryanodine receptor 2 (RyR2), a Ca2+-releasing channel in the sarcoplasmic reticulum (SR), is an essential ion channel for the control of [Ca2+]i in pulmonary artery SMCs (PASMCs), thereby mediating the sustained vasoconstriction seen in PH. FK506-binding protein 12.6 (FKBP12.6) strongly associates with RyR2 to stabilize its functional activity. FKBP12.6 can be dissociated from RyR2 by a hypoxic stimulus to increase channel function and Ca2+ release, leading to pulmonary vasoconstriction and PH. More specifically, dissociation of the RyR2-FKBP12.6 complex is a consequence of increased mitochondrial ROS generation mediated by the Rieske iron-sulfur protein (RISP) at the mitochondrial complex III after hypoxia. Overall, RyR2/FKBP12.6 dissociation and the corresponding signaling pathway may be an important factor in the development of PH. Novel drugs and biologics targeting RyR2, FKBP12.6, and related molecules may become unique effective therapeutics for PH.

Pathophysiology and new advances in pulmonary hypertension

Pulmonary hypertension is a progressive and often fatal cardiopulmonary condition characterised by increased pulmonary arterial pressure, structural changes in the pulmonary circulation, and the formation of vaso-occlusive lesions. These changes lead to increased right ventricular afterload, which often progresses to maladaptive right ventricular remodelling and eventually death. Pulmonary arterial hypertension represents one of the most severe and best studied types of pulmonary hypertension and is consistently targeted by drug treatments. The underlying molecular pathogenesis of pulmonary hypertension is a complex and multifactorial process, but can be characterised by several hallmarks: inflammation, impaired angiogenesis, metabolic alterations, genetic or epigenetic abnormalities, influence of sex and sex hormones, and abnormalities in the right ventricle. Current treatments for pulmonary arterial hypertension and some other types of pulmonary hypertension target pathways involved in the control of pulmonary vascular tone and proliferation; however, these treatments have limited efficacy on patient outcomes. This review describes key features of pulmonary hypertension, discusses current and emerging therapeutic interventions, and points to future directions for research and patient care. Because most progress in the specialty has been made in pulmonary arterial hypertension, this review focuses on this type of pulmonary hypertension. The review highlights key pathophysiological concepts and emerging therapeutic directions, targeting inflammation, cellular metabolism, genetics and epigenetics, sex hormone signalling, bone morphogenetic protein signalling, and inhibition of tyrosine kinase receptors.

Combined pre- and post-capillary pulmonary hypertension in left heart disease

Patients with heart failure (HF) often have pulmonary hypertension (PH), which is mainly post-capillary; however, some of them also develop a pre-capillary component. The exact mechanisms leading to combined pre- and post-capillary PH are not yet clear, but the phenomenon seems to start from a passive transmission of increased pressure from the left heart to the lungs, and then continues with the remodeling of both the alveolar and vascular components through different pathways. More importantly, it is not yet clear which patients are predisposed to develop the disease. These patients have some characteristics similar to those with idiopathic pulmonary arterial hypertension (e.g., young age and frequent incidence in female gender), but they share cardiovascular risk factors with patients with HF (e.g., obesity and diabetes), with both reduced and preserved ejection fraction. Thanks to echocardiography parameters and newly introduced scores, more tools are available to distinguish between idiopathic pulmonary arterial hypertension and combined PH and to guide patients' management. It may be hypothesized to treat patients in whom the pre-capillary component is predominant with specific therapies such as those for idiopathic pulmonary arterial hypertension; however, no adequately powered trials of PH-specific treatment are available in combined PH. Early evidence of clinical benefit has been proven in some trials on phosphodiesterase type 5 inhibitors, while data on prostacyclin analogues, endothelin-1 receptor antagonists, and soluble guanylate cyclase stimulators are still controversial.

The Therapeutic Role of Rho Kinase Inhibitor, Fasudil, on Pulmonary Hypertension; a Systematic Review and Meta-Analysis

BACKGROUND

Pulmonary hypertension (PH) is a pathophysiological disorder, which involves multiple clinical conditions such as the upregulation of the Rho/ROCK signaling pathway. On the other hand, fasudil as a Rho kinase inhibitor has been investigated in the treatment of PH in some clinical studies.

OBJECTIVES

The present systematic review and meta-analysis aimed to evaluate the human clinical trials regarding the efficacy of fasudil in the management of PH.

METHODS

Databases were searched with pre-defined search terms, up to December 2021. Efficacy measures were such as mean pulmonary arterial pressure (mPAP), systolic PAP (sPAP), pulmonary vascular resistance (PVR), systolic vascular resistance (SVR) and cardiac index (CI).

RESULTS

A total of 12 studies involving 575 PH patients were included in our research. Eight short-term trials and four mid-term trials were found (no clinical trials on the long-term effects). Short-term trials had a before-after study design and measuring pulmonary hemodynamic parameters' intervention revealed a statistically significant improvement of mPAP, sPAP, PVR, SVR, and CI in the meta-analysis of five eligible studies. Three mid-term trials also revealed improvement in some pulmonary hemodynamic parameters with fasudil and in another mid-term trial, fasudil significantly decreased rehospitalization and mortality in PH patients. No serious adverse effects with fasudil were reported in these trials.

CONCLUSION

Fasudil therapy is efficacious and probably safe in the improvement of some hemodynamics in PH patients along short and mid-term periods. However, long-term randomized controlled trials comparing fasudil with placebo and other treatments are warranted for confirmation of these benefits.

Influence of Iron Deficiency on Clinical and Haemodynamic Parameters in Pulmonary Arterial Hypertension Cohorts

BACKGROUND

Iron deficiency (Fe_def) has been shown to be common in patients with group 1 or pulmonary arterial hypertension (PAH). Several studies have shown a negative impact of Fe_def on clinical and haemodynamic parameters of the disease, but data from individual studies have not been strong enough to lead to incorporation of the finding of Fe_def into prognostic or therapeutic algorithms. The goal of this meta-analysis was to combine data from available studies to better define any associations between Fe_def and established variables of prognostic importance in PAH.

METHODS

A literature search identified nine studies with extractable data relevant to the study questions. The impact of Fe_def upon the following parameters was evaluated: 6-minute walk distance (6MWD), WHO-functional class, N-terminal pro-brain natriuretic peptide (NT-proBNP) levels, echocardiography, and findings from right heart catheterisation (RHC). Pooled results were reported as mean difference or risk difference with 95% confidence intervals utilising a random effects modeling approach.

RESULTS

Fe_def in the PAH population was common (47% of cases) and was associated with cardiovascular dysfunction (lower tricuspid annular plane systolic excursion [TAPSE], elevated NT-proBNP, and lower mixed venous oxygen saturation) and with reduction in functional capacity (lower 6MWD and higher functional class).

CONCLUSION

This meta-analysis strengthens the relationships between Fe_def and several markers of poor outcome in PAH. Fe_def in patients with PAH warrants further scrutiny and merits consideration as a cause of clinical deterioration. Even though causation and longitudinal relationships between Fe_def and PAH could not be identified, effect of Fe_def on factors that affect disease prognosis is noteworthy and worthy of more focussed studies.

ACR Appropriateness Criteria® Suspected Pulmonary Hypertension: 2022 Update

Pulmonary hypertension may be idiopathic or related to a large variety of diseases. Various imaging examinations may be helpful in diagnosing and determining the etiology of pulmonary hypertension. Imaging examinations discussed in this document include chest radiography, ultrasound echocardiography, ventilation/perfusion scintigraphy, CT, MRI, right heart catheterization, and pulmonary angiography. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer-reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances in which peer-reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Echocardiographic changes after arteriovenous fistula creation in hemodialysis patients

BACKGROUND

Pulmonary hypertension (PH) is common in end-stage renal disease (ESRD) patients and is associated with increased all-cause and cardiovascular mortality in this group. There is scarce data on the long-term effect of arteriovenous fistula (AVF) creation on pulmonary hypertension (PH) and the reflected changes in echocardiographic measurements.

MATERIALS AND METHODS

This is a retrospective study of 54 patients who underwent AVF creation between 2009 and 2014 and with echocardiographic evaluations before and after surgery. We analyzed pairwise changes in right ventricular systolic pressure (RVSP), right atrial pressure (RAP) during systole, left ventricular mass (LVM), tricuspid regurgitation (TR), mitral E/E' ratio, and ejection fraction (EF), as well as the factors that predicted change in RVSP after surgery.

RESULTS

The median time for the preoperative echocardiogram was 0.3 years (interquartile range (IQR) 0.2 - 0.7 years) prior to AVF creation, while the follow-up echo was done 1.3 (0.6 - 2.1) years after surgery. 67% of the patients had RVSP &gt; 37 mmHg at baseline. There was a significant reduction in RVSP after AVF creation compared to baseline (median 33 (IQR 26 - 43) vs. 46 mmHg, p = 0.0015), with 59% of the patients experiencing a decrease and 19% remaining stable. There were also significant decreases in LVM (201 (143 - 256) vs. 215 (163 - 276), p = 0.045) and RAP systole (10 (10 - 15) vs. 3 (3 - 8); p &lt; 0.001) after surgery. Higher preoperative weight (p = 0.038) and RVSP (p = 0.006), and use of loop diuretics (p = 0.015) were significantly associated with improvement in RVSP after AVF creation.

CONCLUSION

Our results suggest that AVF creation is associated with a significant reduction or stable measurements of RVSP in the ESRD population, likely due to an improvement in volume status.

Non-invasive assessment of HFpEF in mouse models: current gaps and future directions

BACKGROUND

Heart failure (HF) with preserved ejection fraction (HFpEF) prevalence is increasing, and large clinical trials have failed to reduce mortality. A major reason for this outcome is the failure to translate results from basic research to the clinics. Evaluation of HFpEF in mouse models requires assessing three major key features defining this complex syndrome: the presence of a preserved left ventricular ejection fraction (LVEF), diastolic dysfunction, and the development of HF. In addition, HFpEF is associated with multiple comorbidities such as systemic arterial hypertension, chronic obstructive pulmonary disease, sleep apnea, diabetes, and obesity; thus, non-cardiac disorders assessment is crucial for a complete phenotype characterization. Non-invasive procedures present unquestionable advantages to maintain animal welfare and enable longitudinal analyses. However, unequivocally determining the presence of HFpEF using these methods remains challenging.

MAIN TEXT

Transthoracic echocardiography (TTE) represents an invaluable tool in HFpEF diagnosis, allowing evaluation of LVEF, diastolic dysfunction, and lung congestion in mice. Since conventional parameters used to evaluate an abnormal diastole like E/A ratio, isovolumic relaxation time, and E/e' may pose limitations in mice, including advanced TTE techniques to characterize cardiac motion, including an assessment under stress, will improve diagnosis. Patients with HFpEF also show electrical cardiac remodelling and therefore electrocardiography may add valuable information in mouse models to assess chronotropic incompetence and sinoatrial node dysfunction, which are major contributors to exercise intolerance. To complete the non-invasive diagnosis of HF, low aerobic exercise capacity and fatigue using exercise tests, impaired oxygen exchange using metabolic cages, and determination of blood biomarkers can be determined. Finally, since HFpEF patients commonly present non-cardiac pathological conditions, acquisition of systemic and pulmonary arterial pressures, blood glucose levels, and performing glucose tolerance and insulin resistance tests are required for a complete phenotyping.

CONCLUSION

Identification of reliable models of HFpEF in mice by using proper diagnosis tools is necessary to translate basic research results to the clinics. Determining the presence of several HFpEF indicators and a higher number of abnormal parameters will lead to more reliable evidence of HFpEF.

Current status of pulmonary artery denervation

Pulmonary hypertension is a progressive disease with a poor long-term prognosis and high mortality. Pulmonary artery denervation (PADN) is emerging as a potential novel therapy for this condition. The basis of pursuing a sympathetic denervation strategy has its origins in a body of experimental translation work that has demonstrated that denervation can reduce sympathetic nerve activity in various animal models. This reduction in pulmonary sympathetic nerve activity is associated with a reduction in pathological pulmonary hemodynamics in response to mechanical, pharmacological, and toxicologically induced pulmonary hypertension. The most common method of PADN is catheter-directed thermal ablation. Since 2014, there have been 12 reports on the role of PADN in 490 humans with pulmonary hypertension (311:179; treated: control). Of these, six are case series, three are randomized trials, and three are case reports. Ten studies used percutaneous PADN techniques, and two combined PADN with mitral and/or left atrial surgery. PADN treatment has low mortality and morbidity and is associated with an improved 6-minute walking distance, a reduction in both mean pulmonary artery pressure and pulmonary vascular resistance, and an improvement in cardiac output. These improved outcomes were seen over a median follow-up of 12 months (range 2–46 months). A recent meta-analysis of human trials also supports the effectiveness of PADN in carefully selected patients. Based on the current literature, PADN can be effective in select patients with pulmonary hypertension. Additional randomized clinical trials against best medical therapy are required.

Pulmonary Manifestations in Rheumatological Diseases

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

Coping styles associated with depression, health anxiety and health-related quality of life in pulmonary hypertension: cross-sectional analysis

OBJECTIVES

Pulmonary hypertension (PH) is a life-shortening disease associated with early mortality and high morbidity. With advancements in medical treatment, people are living longer with the disease, and research is now needed to explore variables that help to enhance patient-reported outcomes. This study investigated the coping strategies of individuals with PH and examined the relationship between coping, depression, health anxiety and health-related quality of life (HRQoL).

DESIGN

A cross-sectional survey design was used.

PARTICIPANTS

Participants (n=121) were recruited from membership of Pulmonary Hypertension Association (PHA) UK.

OUTCOME MEASURES

Participants completed a series of questionnaires assessing depression (Patient Health Questionnaire-9), health anxiety (Short Health Anxiety Inventory), HRQoL (emPHasis-10) and coping (Brief COPE). A principal component analysis was used to identify participants' coping profile. A series of correlational, linear and moderated multiple regression analyses were performed to examine the relationship between coping and health-related outcomes.

RESULTS

Overall, 43% participants met criteria for potential clinical depression. Depression and health anxiety were strongly associated with HRQoL, explaining 37% and 30% of variance respectively (p<0.001). A principal component analysis identified a four-component model of coping. Dimensions were named based on construct items: 'cognitive and affirmation coping' (seven items), 'passive coping' (four items), 'external coping' (seven items) and 'substance use coping' (two items). Cognitive and affirmation and external coping moderated the relationship between depression and HRQoL, with high use of these coping strategies reducing the impact of depression on HRQoL. External coping also moderated the effect of health anxiety on HRQoL.

CONCLUSIONS

The results uniquely highlight the importance of coping styles and psychological distress in predicting HRQoL in PH. Our findings indicate the importance to assess for psychological distress in this population and suggest the need to offer psychological interventions that take into account coping resources and strategies.

Immune Cells in Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a complex and serious cardiopulmonary disease; it is characterised by increased pulmonary arterial pressure and pulmonary vascular remodelling accompanied by disordered endothelial and smooth muscle cell proliferation within pulmonary arterioles and arteries. Although recent reports have suggested that dysregulated immunity and inflammation are key players in PAH pathogenesis, their roles in PAH progression remain unclear. Intriguingly, altered host immune cell distribution, number, and polarisation within the lung arterial vasculature have been linked to disease development. This review mainly focusses on the roles of different immune cells in PAH and discusses the underlying mechanisms.

Diagnostic value of computed tomography-based pulmonary artery to aorta ratio measurement in chronic obstructive pulmonary disease with pulmonary hypertension: A systematic review and meta-analysis

OBJECTIVE

We conducted a meta-analysis to systematic assess the diagnostic value of computed tomography (CT)-based pulmonary artery to aorta (PA:A) ratio measurement in COPD with pulmonary hypertension (COPD-PH).

METHODS

Published studies referring to diagnostic accuracy of PA:A ratio for COPD-PH were screened out from PubMed, Embase, Web of science, China National Knowledge databases (CNKI), Wan fang databases, and VIP databases. We used bivariate random-effects model to estimate pooled sensitivity (SEN), specificity (SPE), positive and negative likelihood ratios (PLR and NLR, respectively), and diagnostic odds ratios (DOR). Summary receiver operating characteristic (SROC) curves and area under the curve (AUC) were also calculated to summarize the aggregate diagnostic performance.

RESULTS

Nine eligible studies were included and the pooled SEN was 69% (95% CI: 59 ~ 78), SPE was 85% (95% CI: 77 ~ 90), PLR was 4.5 (95% CI: 2.8 ~ 7.5), and NLR was 0.36 (95% CI: 0.26 ~ 0.51), respectively. DOR reached 13.00 (95% CI: 6.00 ~ 28.00), and value of AUC was 0.84 (95% CI: 0.81 ~ 0.87). Subgroup analysis indicated that when the value of PA:A ratio was equal or greater than one (PA/A ≥ 1), the combined SEN, SPE, AUC, and DOR was 69%, 89%, 0.90, and 19.65, respectively.

CONCLUSIONS

PA:A ratio is helpful for appraisal of COPD-PH, and PA/A ≥ 1 possessed prominent diagnostic accuracy.

MMP-10 from M1 macrophages promotes pulmonary vascular remodeling and pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is characterized by muscularized pulmonary blood vessels, leading to right heart hypertrophy and cardiac failure. However, state-of-the-art therapeutics fail to target the ongoing remodeling process. Here, this study shows that matrix metalloproteinases (MMP)-1 and MMP-10 levels are increased in the medial layer of vessel wall, serum, and M1-polarized macrophages from patients with PAH and the lungs of monocrotaline- and hypoxia-induced PAH rodent models. MMP-10 regulates the malignant phenotype of pulmonary artery smooth muscle cells (PASMCs). The overexpression of active MMP-10 promotes PASMC proliferation and migration via upregulation of cyclin D1 and proliferating cell nuclear antigen, suggesting that MMP-10 produced by infiltrating macrophages contributes to vascular remodeling. Furthermore, inhibition of STAT1 inhibits hypoxia-induced MMP-10 but not MMP-1 expression in M1-polarized macrophages from patients with PAH. In conclusion, circulating MMP-10 could be used as a potential targeted therapy for PAH.

Treatment with neurohormonal inhibitors and prognostic outcome in pulmonary arterial hypertension with risk factors for left heart disease

BACKGROUND

Despite major advances in pharmacologic treatment, patients with pulmonary arterial hypertension (PAH) still have a considerably reduced life expectancy. In this context, chronic hyperactivity of the neurohormonal axis has been shown to be detrimental in PAH, thus providing novel insights on the role of neurohormonal blockade as a potential therapeutic target.

AIM

To evaluate the application and prognostic effect of neurohormonal inhibitors (NEUi) in a single-center sample of patients with idiopathic PAH and risk factors for left heart disease.

METHODS

We analyzed data retrospectively collected from our register of right heart catheterizations performed consecutively from January 1, 2005 to October 31, 2018. Patients on beta-blocker, angiotensin-converting enzyme inhibitor, angiotensin receptor blocker or mineralocorticoid receptor antagonist at the time of right heart catheterization were classified as NEUi users and compared to NEUi non-recipients.

RESULTS

Complete data were available for 57 PAH subjects: 27 of those (47.4%) were taking at least one NEUi at the time of right heart catheterization and were compared with the remaining 36 NEUi non-recipients. NEUi users were older and had a higher cardiovascular risk profile compared to non-recipients. Additionally, NEUi non-users had a higher probability of dying during the course of follow-up than NEUi recipients (56.7% vs 25.9%, log-rank P = 0.020).

CONCLUSION

The above data highlighted a subgroup of patients with PAH and comorbidities for left heart disease in which NEUi use has shown to be associated with improved survival. Future prospective studies are needed to identify the most appropriate therapeutic strategies in this subset population.

MiRNAs in Systemic Sclerosis Patients with Pulmonary Arterial Hypertension: Markers and Effectors

Background: Pulmonary arterial hypertension (PAH) is a major cause of death in systemic sclerosis (SSc). Early detection may improve patient outcomes. Methods: We searched for circulating miRNAs that would constitute biomarkers in SSc patients with PAH (SSc-PAH). We compared miRNA levels and laboratory parameters while evaluating miRNA levels in white blood cells (WBCs) and myofibroblasts. Results: Our study found: 1) miR-26 and miR-let-7d levels were significantly lower in SSc-PAH (n = 12) versus SSc without PAH (SSc-noPAH) patients (n = 25); 2) a positive correlation between miR-26 and miR-let-7d and complement-C3; 3) GO-annotations of genes that are miR-26/miR-let-7d targets and that are expressed in myofibroblast cells, suggesting that these miRNAs regulate the TGF-β-pathway; 4) reduced levels of both miRNAs accompanied fibroblast differentiation to myofibroblasts, while macitentan (endothelin receptor-antagonist) increased the levels. WBCs of SSc-noPAH and SSc-PAH patients contained equal amounts of miR-26/miR-let-7d. During the study, an echocardiograph that predicted PAH development, showed increased pulmonary artery pressure in three SSc-noPAH patients. At study initiation, those patients and an additional SSc-noPAH patient, who eventually developed PAH, had miR-let-7d/miR-26 levels similar to those of SSc-PAH patients. This implies that reduced miR-let-7d/miR-26 levels might be an early indication of PAH. Conclusions: miR-26 and miR-let-7d may be serological markers for SSc-PAH. The results of our study suggest their involvement in myofibroblast differentiation and complement pathway activation, both of which are active in PAH development.

Comparison of Risk Stratification Scores in Pulmonary Arterial Hypertension: A Monocentric Retrospective Study at Lausanne University Hospital

BACKGROUND

Risk assessment is the cornerstone of pulmonary arterial hypertension (PAH) management. Risk stratification scores predict prognosis and help individualize treatment.

OBJECTIVES

The aims of the study include the following: (1) to compare the prediction for transplant-free survival (TFs) of 3 risk assessment tools at 3 and 5 years after diagnosis and (2) to analyze whether the initial risk stratification was altered after 1 year of treatment.

METHOD

We collected retrospectively data of 50 patients diagnosed with PAH Group 1. We categorized them as low, intermediate, and high mortality risk at baseline and at 1 year with the (1) Registry to Evaluate Early and Long-Term PAH Disease Management (REVEAL) risk score version 2.0, (2) Swedish/Comparative Prospective Registry of Newly Initiated Therapies for Pulmonary Hypertension (PH) (COMPERA) score, and (3) French PH Network Registry (FPHR) score.

RESULTS

TFs at 3 years is predicted by the 3 scores computed at baseline with an area under the curve (AUC) of 0.73, 0.73, and 0.77, respectively. The predictive value increased when the scores were calculated after 1 year of treatment (AUC = 0.91, 0.89, and 0.78). The prediction of TFs at 5 years was better evaluated by the COMPERA and FPHR (AUC = 0.85) than by REVEAL 2.0 (AUC = 0.69) computed at baseline. A low risk status was associated with excellent TFs whatever the scoring used.

CONCLUSION

In accordance with the original publications, the 3 scores are able to predict survival up to 5 years after diagnosis. The better performance of the scores after 1 year is a further evidence for their clinical use and an indirect proof for treatment efficacy.

Pulmonary Hypertension Is Associated With Systemic Arterial Hypertension Among Patients With Normal Left Ventricular Diastolic Function

Background

The association of pulmonary and systemic arterial hypertension is believed to be mediated through hypertensive left heart disease. The purpose of the current study was to investigate whether pulmonary hypertension (PHT) is associated with systemic arterial hypertension among patients with apparently normal left ventricular diastolic function.

Methods and Results

Consecutive patients who had echocardiographic evaluation between 2007 and 2019 were enrolled. Patients with disease states that are known to be associated with PHT, including diastolic dysfunction, were excluded from the analysis. Estimated right ventricular systolic pressure was extracted for all patients from the echocardiographic reports. PHT was defined as estimated right ventricular systolic pressure >40 mm Hg. Multivariate logistic regression models were applied. Final study population included 25 916 patients with a median age of 59 (interquartile range, 44–69) years, of whom 12 501 (48%) were men and 13 265 (51%) had systemic arterial hypertension. Compared with normotensive patients, hypertensive patients were 3.2 times more likely to have PHT (95% CI, 2.91–3.53; P<0.001). A multivariate model adjusted for clinical and echocardiographic parameters that are known to be associated with PHT demonstrated that hypertensive patients are almost 3 times more likely to have PHT (95% CI, 2.45–3.15; P<0.001). The association was significant in multiple subgroups but was more significant among women compared with men (odds ratio, 3.1 versus 2.4; P for interaction <0.001).

Conclusions

PHT is associated with systemic arterial hypertension irrespective of left heart disease. The association is more pronounced among women.

Identification of novel metabolic signatures potentially involved in the pathogenesis of COPD associated pulmonary hypertension

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) associated pulmonary hypertension (COPD-PH), one of the most prevalent forms of PH, is a major burden on the healthcare system. Although PH in COPD is usually of mild-to-moderate severity, its presence is associated with shorter survival, more frequent exacerbations and worse clinical outcomes. The pathophysiologic mechanisms responsible for PH development in COPD patients remain unclear. It is envisioned that a better understanding of the underlying mechanism will help in diagnosis and future treatment strategies.

OBJECTIVES

The present study aims to determine metabolomic alterations in COPD-PH patients as compared to healthy controls. Additionally, to ensure that the dysregulated metabolites arise due to the presence of PH per se, an independent COPD cohort is included for comparison purposes.

METHODS

Paired serum and exhaled breath condensate (EBC) samples were collected from male patients with COPD-PH (n = 60) in accordance with the 2015 European Society of Cardiology (ESC)/European Respiratory Society (ERS) guidelines. Age, sex and BMI matched healthy controls (n = 57) and COPD patients (n = 59) were recruited for comparison purposes. All samples were characterized using ¹H nuclear magnetic resonance (NMR) spectroscopy.

RESULTS

Fifteen serum and 9 EBC metabolites were found to be significantly altered in COPD-PH patients as compared to healthy controls. Lactate and pyruvate were dysregulated in both the biofluids and were further correlated with echocardiographic systolic pulmonary artery pressure (sPAP). Multivariate analysis showed distinct class separation between COPD-PH and COPD.

CONCLUSIONS

The findings of this study indicate an increased energy demand in patients with COPD-PH. Furthermore, both lactate and pyruvate correlate with sPAP, indicating their importance in the clinical course of the disease.

Echocardiography in Pulmonary Arterial Hypertension: Comprehensive Evaluation and Technical Considerations

Pulmonary arterial hypertension (PAH) is a rare, progressive disease in which there is a persistent, abnormal increase in pulmonary artery pressure. Symptoms of pulmonary hypertension are nonspecific and mainly associated with progressive right ventricular failure. The diagnosis of PAH is a multistep process and often requires the skillful use of several tests. The gold standard for the diagnosis of PAH is hemodynamic testing. Echocardiography currently plays an important role in the diagnostic algorithm of PAH as it is minimally invasive and readily available. Moreover, many echocardiographic parameters are closely related to pulmonary hemodynamics. It allows assessment of the right heart′s structure and function, estimation of the pressure in the right ventricle, right atrium, and pulmonary trunk, and exclusion of other causes of elevated pulmonary bed pressure. Echocardiographic techniques are constantly evolving, and recently, measurements made using new techniques, especially 3D visualization, have become increasingly important. In echocardiographic assessment, it is crucial to know current guidelines and new reports that organize the methodology and allow standardization of the examination. This review aims to discuss the different echocardiographic techniques used to evaluate patients with PAH.

Substantial involvement of TRPM7 inhibition in the therapeutic effect of Ophiocordyceps sinensis on pulmonary hypertension

Ophiocordyceps sinensis (OCS), an entomopathogenic fungus, is known to exert antiproliferative and antitissue remodeling effects. Vascular remodeling and vasoconstriction play critical roles in the development of pulmonary hypertension (PH). The therapeutic potential of OCS for PH was investigated using rodent PH models, and cultured pulmonary artery endothelial and smooth muscle cells (PAECs and PASMCs), with a focus on the involvement of TRPM7. OCS ameliorated the development of PH, right ventricular hypertrophy and dysfunction in the monocrotaline-induced PH rats. The genetic knockout of TRPM7 attenuated the development of PH in mice with monocrotaline pyrrole-induced PH. TRPM7 was associated with medial hypertrophy and the plexiform lesions in rats and humans with PH. OCS suppressed proliferation of PASMCs derived from the PH patients. Ethanol extracts of OCS inhibited TRPM7-like current, TGF-β2-induced endothelial-mesenchymal transition, IL-6-induced STAT3 phosphorylation, and PDGF-induced Akt phosphorylation in PAECs or PASMCs. These inhibitory effects were recapitulated by either siRNA-mediated TRPM7 knockdown or treatment with TRPM7 antagonist FTY-720. OCS and FTY-720 induced vasorelaxation in the isolated normal human pulmonary artery. As a result, the present study proposes the therapeutic potential of OCS for the treatment of PH. The inhibition of TRPM7 is suggested to underlie the therapeutic effect of OCS.

Limited Scleroderma-Induced Pulmonary Arterial Hypertension Resulting in Impaired Postoperative Respiratory Function

Limited scleroderma falls under the umbrella of systemic sclerosis, an autoimmune disease that presents with multiorgan dysfunction that includes pulmonary arterial hypertension. We examine a case of pulmonary arterial hypertension in an elderly nonsmoker with a history of limited scleroderma. 

The patient presented with abdominal tenderness and was diagnosed with a sigmoid colonic stricture. She underwent laparoscopic bowel resection. During and after her surgery, she suffered from worsening respiratory function and decompensated, developing a large pleural effusion that led to a thoracentesis and a prolonged hospital course.

Patients with scleroderma can develop acute symptoms involving several organ systems, including the colonic tract and lungs, as seen in our patient. A thorough workup and continuous close management and monitoring are necessary to avoid further complications in these patients, especially in the postoperative period.

Effect of exercise on sleep and cardiopulmonary parameters in patients with pulmonary artery hypertension

BACKGROUND

Pulmonary arterial hypertension (PAH) is considered to be a rare progressive disease resulting from restricted flow through the pulmonary arterial circulation resulting ultimately in right-sided heart failure. Most patients with PAH suffer from sleep disorders, reduced aerobic fitness, and mortality risk despite optimized medical treatment. This study investigated the effect of 12 weeks of aerobic training on sleep quality, sleep efficiency, right ventricular systolic pressure (RVSP), and aerobic fitness in patients with PAH.

METHODS

Thirty patients with PAH were randomized to two equal groups, training group (A) and control group (B). The Pittsburg sleep quality index (PSQI) questionnaire and a wrist-worn actigraph were used for the assessment of sleep quality and sleep efficiency respectively. RVSP was measured using echocardiography. Cardiopulmonary exercise testing (CPET) assessed maximal heart rate and VO2max. All were measured before and after the study period for both groups. Exercise training was conducted on a bicycle ergometer as an individually-tailored moderate-intensity aerobic training session (60 to 70% of the maximal heart rate reached during the initial exercise test) for 30 to 45 min/day, 3 sessions/week for 12 weeks (36 sessions).

RESULTS

Sleep scores and RVSP showed significant reductions and VO2max-representing the aerobic fitness-showed a significant increase in the group (A) compared with group (B).

CONCLUSION

These results suggest that aerobic training has a positive effect on three risk factors for mortality in patients with PAH, namely sleep quality, decline in exercise capacity, and right ventricular remodeling.

CLINICAL TRIALS REGISTRATION

Clinical trial registered in ClinicalTrials.gov , ID: NCT04337671.

The diagnostic challenge in pulmonary tumour embolism in cancer: a case report and literature review

Pulmonary tumour embolism is a rare condition without specific symptoms or pathognomonic features. Pulmonary tumour embolism can occur as the first manifestation of cancer, but because of diagnostic difficulties, it is often wrongly recognised as a more common cardiopulmonary disease. We present a case of a 46-year-old Caucasian male with no prior malignancy diagnosis, admitted because of progressing dyspnoea and cough. Based on radiological and clinical presentations, sarcoidosis, silicosis and lymphangitic carcinomatosis were considered in the differential diagnosis. Histopathological analysis of lung biopsy revealed that multiple emboli of atypical epithelial cells found in the pulmonary vessels were of gastrointestinal origin. Further pathological examination of the gastric biopsy led to the final diagnosis of the signet-ring cells gastric adenocarcinoma. The patient was referred for chemotherapy. After a short-term partial remission, he died within two months after the final diagnosis. The presented case illustrates challenges posed by the diagnostic process of pulmonary tumour embolism.

Optimal Cut-Off of Tricuspid Regurgitation Velocity According to the New Definition of Pulmonary Hypertension ― Its Use in Predicting Pulmonary Hypertension ―

Background: The 6th World Symposium on Pulmonary Hypertension proposed that precapillary pulmonary hypertension (PH) be defined as mean pulmonary arterial pressure (mPAP) >20 mmHg instead of mPAP ≥25 mmHg. Peak tricuspid regurgitation velocity (TRV) >3.4 m/s is widely used to predict PH, but it is unclear whether this value remains reliable for the new definition of PH.

Methods and Results: We found that the optimal cut-off value of peak TRV for 511 PH patients was >2.8 m/s, with a sensitivity of 89.5%, specificity of 73.4%, and area under the curve of 0.89 (P<0.001).

Conclusions: Based on the new definition of PH, TRV >2.8 m/s can be considered to indicate a high probability of PH.

Phosphodiesterases in the Liver as Potential Therapeutic Targets of Cirrhotic Portal Hypertension

Liver cirrhosis is a frequent condition with high impact on patients' life expectancy and health care systems. Cirrhotic portal hypertension (PH) gradually develops with deteriorating liver function and can lead to life-threatening complications. Other than an increase in intrahepatic flow resistance due to morphological remodeling of the organ, a functional dysregulation of the sinusoids, the smallest functional units of liver vasculature, plays a pivotal role. Vascular tone is primarily regulated by the nitric oxide-cyclic guanosine monophosphate (NO-cGMP) pathway, wherein soluble guanylate cyclase (sGC) and phosphodiesterase-5 (PDE-5) are key enzymes. Recent data showed characteristic alterations in the expression of these regulatory enzymes or metabolite levels in liver cirrhosis. Additionally, a disturbed zonation of the components of this pathway along the sinusoids was detected. This review describes current knowledge of the pathophysiology of PH with focus on the enzymes regulating cGMP availability, i.e., sGC and PDE-5. The results have primarily been obtained in animal models of liver cirrhosis. However, clinical and histochemical data suggest that the new biochemical model we propose can be applied to human liver cirrhosis. The role of PDE-5 as potential target for medical therapy of PH is discussed.

The roles of endothelin and its receptors in cigarette smoke-associated pulmonary hypertension with chronic lung disease

Chronic exposure to cigarette smoke is the major risk factor for the development of pulmonary hypertension (PH) with chronic lung disease (i.e. PH group III). The pathogenesis of smoke-associated PH group III in chronic obstructive pulmonary disease (COPD) involves cigarette smoke exposure-induced damage to lung tissue and dysfunction of pulmonary system with increased synthesis and release of endothelin-1 (ET-1), hypoxia, inflammation, pulmonary vascular remodeling. Many studies have demonstrated that cigarette smoke exposure induces activation of mitogen-activated protein kinase (MAPK) signal pathway that leads to up-regulation of ET-1 and its receptors with the receptor-mediated enhanced contraction, proliferation of pulmonary vascular smooth muscle cells, pulmonary vascular remodeling, elevated pulmonary arterial pressure and finally PH group III. This mini-review article aims to summarize the current state of understanding on the roles of cigarette smoke-induced up-regulation of ET-1 and its receptors in the development of PH group III. Understanding the underlying molecular mechanisms that cigarette smoke exposure leads to PH group III may provide a novel strategy for the treatment.