Guidelines on the Diagnosis and Treatment of Pulmonary Hypertension: Summary of Recommendations

Pulmonary artery pressure assessed by catheterization and its concordance with transthoracic echocardiographic estimates in patients with pulmonary arterial hypertension: experience of the Colombian Pulmonary Hypertension Network in a real-life study

OBJECTIVE

To evaluate the correlation and concordance of pulmonary artery systolic pressure values measured via right heart catheterization and estimated via transthoracic echocardiography based on data from a multicenter cohort of patients with pulmonary hypertension in Colombia.

METHODS

A retrospective study was conducted of patients with pulmonary hypertension classified into Groups 1 or 4 according to the definitions of the ESC/ERS-PH-2022 guidelines. Patients were obtained from the Colombian Pulmonary Hypertension Network (HAPredco) database.

RESULTS

A total of 633 patients were identified and included in this study. Among these patients, 77.7% (n = 492) had complete data from transthoracic echocardiography at diagnosis, 58,3% (n = 369) had complete data from right heart catheterization at the time of diagnosis, and 264 (41.7%) had complete data from both tests at diagnosis, with a difference in days between them of 1 (84). The values of pulmonary artery systolic pressure estimated by transthoracic echocardiography and those obtained by right heart catheterization were significantly correlated (p < 0.001) in the entire population evaluated, as was the correlation assessed for those patients with a gap of ≤ 7 days (p = 0.0001) or ≤ 48 hours (p = 0.041) between the two examinations; however, these findings presented a low Spearman (0.32 for ≤ 7 days and 0.264 for ≤ 48 hours) and Lin´s correlation coefficient (0.32 for ≤ 7 days and 0.21 for ≤ 48 hours).

CONCLUSION

The pulmonary artery systolic pressure values estimated via transthoracic echocardiography and measured via right heart catheterization were significantly but weakly linearly correlated, with low concordance. These findings suggest interindividual variability between the pulmonary artery systolic pressure values obtained by the two methods, which may have clinical significance in follow-up and decision-making.

Knockdown of PLOD2 inhibits pulmonary artery smooth muscle cell glycolysis under chronic intermittent hypoxia via PI3K/AKT signal

OBJECTIVE

This study aimed to investigate the role and potential mechanism of procollagen-lysine, 2-oxoglutarate 5-dioxygenase 2 (PLOD2) in chronic intermittent hypoxia (CIH)-induced mice and pulmonary arterial smooth muscle cells (PASMCs).

METHODS

CIH mouse model was pre-injected with AAV-shPLOD2 by tail vein, and the pathological changes of lung was evaluated using hematoxylin-eosin (H&E) and α-SMA immunostaining. Enriched KEGG pathway analyses of PLOD2 targeted genes were performed using GSE11341 and GSE131425 datasets. Next, primary PASMCs were exposed to CIH environment, and then measured its proliferation, migration and glycolysis by CCK8, EdU assay, wound healing assay, Transwell and western blotting.

RESULTS

PLOD2 expression was increased in the lungs of CIH-induced mice and in PASMCs under CIH conditions. Moreover, glycolysis and PI3K/AKT pathway were regulated by PLOD2. Silencing of PLOD2 significantly inhibited the increase of RV/(LV + S) and RVSP, alleviated pathological changes of lung in CIH-induced mice and restrained the proliferation, migration, glycolysis and activation of PI3K/AKT in CIH-induced PASMCs. The inhibitory effects of PLOD2 silencing on PASMC proliferation and migration were accelerated by 2-DG (an inhibitor of glycolysis) and were reversed by lactate (the end product of glycolysis). In addition, the inhibitory effects of PLOD2 silencing on PASMC proliferation, migration and glycolysis were accelerated by PI3K/AKT inhibitor LY294002 and were reversed by the agonist 740Y-P.

CONCLUSIONS

Silencing of PLOD2 inhibits PI3K/AKT signaling to limit PASMC glycolysis which allows PASMC proliferation and migration in CIH-induced pulmonary arterial hypertension (PAH).

The impact of pulmonary hypertension on prognosis in moderate-to-severe mitral regurgitation patients treated with transcatheter edge-to-edge mitral valve repair: a comprehensive meta-analysis

Objective

This meta-analysis aims to assess the impact of pulmonary hypertension (PH) on the clinical prognosis of patients with moderate to severe mitral valve regurgitation (MR) undergoing transcatheter edge-to-edge mitral valve repair (TEER).

Methods

As of August 2024, relevant studies were identified through searches of the PubMed, Cochrane Library, Web of Science, and Embase databases. A comprehensive screening process was conducted, with quality assessment performed utilizing the Newcastle Ottawa Scale (NOS). Data analysis was carried out using Stata17.0 software, generating forest plots, funnel plots, Egger's test, and sensitivity analysis plots to analyze heterogeneity and publication bias. Odds ratios (OR) and standardized mean differences (SMD) were calculated for dichotomous and continuous variables, respectively, each presented with a 95% confidence interval (CI).

Results

A total of 10 studies involving 28,404 patients were included, with all articles achieving a NOS score of ≥7. The outcome indicators were as follows: 2-year all-cause mortality [OR = 2.06, 95%CI(1.49, 2.84), p < 0.01, I 2 = 79.9%]; heart failure rehospitalization rate [OR = 1.56, 95%CI(1.29,1.76), p < 0.01, I 2 = 41.7%]; 30-day all-cause mortality [OR = 2.10, 95%CI(1.78,2.47), p < 0.01, I 2 = 0%]; cardiogenic mortality [OR = 2.00, 95%CI (1.61,2.49), p < 0.01, I 2 = 0%]; and length of hospital stay [OR = 0.17, 95%CI(0.14,0.20), p < 0.01, I 2 = 0%]. All outcome indicators demonstrated that the PH group had significantly worse outcomes compared to the non-PH group. Subgroup analyses were performed on outcome indicators with notable heterogeneity, focusing on PH measurement methods, PH diagnostic criteria, and the severity of PH. The results indicated that most combined subgroup outcomes were consistent with the overall findings and showed significantly reduced heterogeneity. The sources of heterogeneity are likely attributed to the methods of PH measurement, diagnostic criteria for PH, and the severity of PH.

Conclusion

Within two years after undergoing transcatheter edge-to-edge repair (TEER), patients with MR and PH experiecne significantly higher rates of all-cause mortality, 30-day all-cause mortality, heart failure readmissions, cardiogenic mortality, and longer hospital stays compared to those without PH.

Systematic Review Registration

https://inplasy.com/, identifier (INPLASY202480068).

Unprecedented Approach for Using Misoprostol Alongside Low-Dose Gamma Radiation to Alleviate Paraquat-Induced Pulmonary Injury in Rats

Background

Abrupt inflammation and alveolar epithelial membrane damage, which may cause the alveolar membrane's malfunction, are related to acute lung injury (ALI). This could eventually lead to pulmonary fibrosis. While lung injury can happen in many ways, the current study will concentrate on the changes in lung pathology mediated by paraquat (PQ). Paraquat, a widely used herbicide, targets lung toxicity through inflammation and oxidative stress, which significantly contribute to lung damage.

Objective

The current research was to ascertain whether low-dose gamma radiation (R) and misoprostol (MP) could lessen the lung inflammatory cascade started by PQ injection in rats.

Methods

The ALI model was induced by I.P. injection of PQ (20 mg/kg once), and then treatment was done by MP and/or R for 14 days, and finally, the biochemical and histological parameters were measured in the lung tissues.

Results

Our data suggest that PQ can promote ALI through TGF-β/smad, Notch, NF-κB, and ET-1 signaling pathways, resulting in EMT. These suggestions were supported by increased levels of TGF-β, inflammatory cytokines, α-SMA, NF-κB, ET-1, CTGF protein, and LPA, whereas PPAR-γ decreased. The aforementioned results have been confirmed by lung histopathology.

Conclusion

We suggest that the pulmonary inflammatory cascade was hindered and all the previously described gauges improved with R and/or MP therapy.

The specific medications for pulmonary arterial hypertension at functional class III to IV: a systematic review and meta-analysis

Purpose

To systematically evaluate the clinical efficacy and safety of targeted drugs in patients with pulmonary arterial hypertension (PAH) with cardiac function grades III-IV, and conduct a meta-analysis.

Methods

Two researchers independently searched the PubMed, EMBASE, and Cochrane Library databases for relevant studies, with the search period extending from the establishment of the databases to March 2024. Meta-analysis was performed using statistical software Review Manager 5.4. Heterogeneity among studies was analyzed using either a random-effects model or a fixed-effects model. When the I2 value was < 50%, indicating good homogeneity, the fixed-effects model was adopted; otherwise, the random-effects model was used. For continuous variables, the 6-minute walk distance (6MWD) was expressed as the mean difference (MD), while hemodynamic parameters were represented by the standard mean difference (SMD). For categorical variables, the odds ratio (OR) was used. The confidence interval (CI) was set at 95%, and a p < 0.05 was considered statistically significant.

Results

Ten randomized controlled trials (RCTs) involving 553 patients with PAH and cardiac function grades III-IV were ultimately included. Three RCTs targeted the endothelin pathway, five targeted the prostacyclin pathway, and two assessed the effects of combination therapy. Meta-analysis and subgroup analysis revealed that short-term monotherapy with bosentan significantly improved 6MWD by ~53.67 m (95% CI: [43.57, 63.77] meters, p < 0.0001) in patients with FC III-IV PAH. Additionally, prostacyclin analogs increased 6MWD by approximately 25.02 meters (95% CI: [19.22, 30.81] meters, p < 0.0001) in this patient population. Further hemodynamic assessments demonstrated that both bosentan monotherapy and prostacyclin analog therapy significantly reduced pulmonary vascular resistance, with SMDs of -1.07 (95% CI [-2.08, -0.06], p = 0.04) and -1.26 (95% CI = [-2.21, -0.32], p = 0.009), respectively. Analysis of the clinical efficacy of combination therapy in PAH patients revealed that while it did not significantly improve 6MWD, cardiac function improved in ~59.1% of patients (95% CI=[38.5%, 79.6%]). Safety analysis indicated that combination targeted therapy did not significantly increase the incidence of severe adverse events in PAH patients.

Conclusion

Monotherapy with targeted drugs is safe and effective for patients with PAH and cardiac function grades III-IV. Combination therapy can significantly improve cardiac dysfunction in these patients without significantly increasing the risk of severe adverse events. Therefore, bosentan and prostacyclin analogs are both safe and effective options for patients with PAH and cardiac function grades III-IV. However, early combination therapy may have added clinical value in improving exercise tolerance, cardiac function, and cardiovascular remodeling in this patient population.

The Relevance of the Endothelium in Cardiopulmonary Disorders

The endothelium is a cell monolayer that lines vessels and separates tissues from blood flow. Endothelial cells (ECs) have a multitude of functions, including regulating blood flow and systemic perfusion through changes in vessel diameter. When an injury occurs, the endothelium is affected by altering its functions and structure, which leads to endothelial dysfunction, a characteristic of many vascular diseases. Understanding the role that the endothelium plays in pulmonary vascular and cardiopulmonary diseases, and exploring new therapeutic strategies is of utmost importance to advance clinically. Currently, there are several treatments able to improve patients' quality of life, however, none are effective nor curative. This review examines the critical role of the endothelium in the pulmonary vasculature, investigating the alterations that occur in ECs and their consequences for blood vessels and potential molecular targets to regulate its alterations. Additionally, we delve into promising non-pharmacological therapeutic strategies, such as exercise and diet. The significance of the endothelium in cardiopulmonary disorders is increasingly being recognized, making ECs a relevant target for novel therapies aimed at preserving their functional and structural integrity.

Prescription patterns of ambrisentan in some cities of Colombia

INTRODUCTION

Ambrisentan is a selective type A endothelin receptor antagonist that has shown significant effectiveness and safety in the management of patients with pulmonary hypertension. Its use pattern with real-world evidence in Colombia is unknown.

OBJECTIVE

The objective of this study is to determine the prescription patterns of ambrisentan in some cities of Colombia.

METHODS

A longitudinal descriptive study on the prescription patterns of ambrisentan in patients with pulmonary hypertension (all the groups) was conducted between January 2021 and December 2022 based on a population database of members of the Colombian Health System. Adherence at 1 year was determined using the Medication Possession Ratio (days the drug was dispensed/days from first dispensing to the end of the follow-up period × 100). Descriptive analysis was carried out.

RESULTS

Sixty-seven patients taking ambrisentan were identified in 10 cities of the country. The individuals had a median age of 51.5 years (interquartile range-IQR: 39.8-64.0 years), and 82.1% were women. The drug possession rate was 82.2% (IQR: 65.0-96.8%), and persistence at 1 year was present in 49.3% (n = 33) of the cases. The average dose was 8.8 ± 5.0 mg/day, and 76.1% (n = 51) received it in combination therapy, mainly with phosphodiesterase type 5 inhibitors (61.2%, n = 41).

CONCLUSIONS

Adherence to ambrisentan was good, but its persistence at 1 year was low. The dosages of the drug used were in accordance with the recommendations of the clinical practice guidelines, and it was used in combination therapy, especially with phosphodiesterase 5 inhibitors.

Role of macrophages in pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a severe cardiopulmonary vascular disease characterized by progressive pulmonary artery pressure elevation, increased pulmonary vascular resistance and ultimately right heart failure. Studies have demonstrated the involvement of multiple immune cells in the development of PAH in patients with PAH and in experimental PAH. Among them, macrophages, as the predominant inflammatory cells infiltrating around PAH lesions, play a crucial role in exacerbating pulmonary vascular remodeling in PAH. Macrophages are generally polarized into (classic) M1 and (alternative) M2 phenotypes, they accelerate the process of PAH by secreting various chemokines and growth factors (CX3CR1, PDGF). In this review we summarize the mechanisms of immune cell action in PAH, as well as the key factors that regulate the polarization of macrophages in different directions and their functional changes after polarization. We also summarize the effects of different microenvironments on macrophages in PAH. The insight into the interactions between macrophages and other cells, chemokines and growth factors may provide important clues for the development of new, safe and effective immune-targeted therapies for PAH.

Characterization of Doppler spectrum of hepatic veins in dogs with pulmonary hypertension

Pulmonary hypertension (PH) triggers hemodynamic changes within the right heart, which may affect hepatic venous flow. The aims of this study were three-fold: to investigate, prospectively, the reliability of the hepatic vein Doppler waveform to diagnose and characterize the magnitude of PH in dogs; to evaluate whether a correlation exists between hepatic venous flow waves and the structural and functional characteristics of the right ventricle (RV); and to determine whether age, gender, body weight, heart rate (HR), heart rhythm and systolic blood pressure affect the hepatic venous waveform pattern. A cross-sectional observational study was carried out in 43 dogs with varying degrees of PH and a control group of 15 healthy dogs. The velocities of the hepatic A, S, V and D spectral waves and the phasic pattern varied according to the severity of PH. Weak to moderate correlations were documented between hepatic vein waves and age, HR, and the structural and functional variables of the RV. A D Wave cut-off of 11.6 cm ∙ s-1 had a sensitivity of 100% and specificity of 35% for differentiation of dogs with severe PH from healthy dogs. Doppler assessment of hepatic venous flow was shown to be a reliable technique for screening dogs for PH.

Advances in the Study of Inhaled Formulations for the Treatment of Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a serious disease with reduced systemic circulation and low bioavailability associated with conventional and dosed therapy, which inhaled drugs can avoid. A mean pulmonary artery pressure (mPAP) of ≥25 mmHg (1 mmHg = 0.133 kPa) at rest or ≥30 mmHg during exercise and a pulmonary capillary pressure or left atrial pressure (PLA) of ≤15 mmHg can be diagnosed with PAH. Pulmonary hypertension is classified into primary PAH and secondary PAH according to the presence or absence of principles or risk factors. The main symptoms of pulmonary hypertension include dyspnoea, syncope, weakness, chest pain, and the presence of varying degrees of peripheral oedema. It is a highly pathogenic and life-threatening disease and can lead to delays in treatment if not diagnosed in time. In the past few years, the studies related to this progressed slowly, which brought great harm to patients with PAH. Reports showed that patients diagnosed with PAH should receive routine preventative care, such as pneumococcal and influenza vaccinations. Inhalation therapy is mainly used for the treatment of respiratory diseases and is of great interest due to the concentration of the drug in the airways and lung tissues. Therefore, the present situation of pulmonary hypertension and the characteristics of inhalation preparation were reviewed in this paper to provide some related cue for the treatment of pulmonary hypertension. In the future, it is necessary to develop more treatment methods for pulmonary hypertension.

Orphan Drug Use in Patients With Rare Diseases: A Population-Based Cohort Study

Background: Orphan drugs are used for the diagnosis, prevention and treatment of rare diseases that, in the European Union, are defined as disorders affecting no more than 5 persons in 10,000. So far, a total of around 800 orphan medicinal products have been approved by the European Medicines Agency, however the utilization profile of orphan drugs has yet to be explored. This study aimed at assessing the utilization profile of orphan drugs authorized for marketing by the Italian Medicines Agency using population-based data. Methods: A total of 21 orphan drugs used in outpatient settings, approved in the European Union before or during the 2008-2018 period and involving 15 rare diseases, were included in the study. The monitored population included patients with one of the conditions surveilled by the population-based Tuscany Registry of Rare Diseases and diagnosed between 2000-2018. A multi-database approach was applied, by linking data from the registry with information collected in drug prescriptions databases. The prevalence and intensity of use were estimated for the selected orphan drugs and other non-orphan medications, used to treat the same rare disease and for which a change in the prevalence of use was hypothesized after authorization of the orphan drug. Results: For some diseases (acquired aplastic anemia, tuberous sclerosis complex, most metabolic diseases) a low prevalence of orphan drugs use was observed (range between 1.1-12.5%). Conversely, orphan drugs were frequently used in hemophilia B, Wilson disease and idiopathic pulmonary fibrosis (maximum of 78.3, 47.6 and 41.8%, respectively). For hemophilia B and Leber's hereditary optic neuropathy, there are currently no other medications used in clinical practice in addition to orphan drugs. Six orphan drugs were used for the treatment of pulmonary arterial hypertension, appearing the elective therapy for this disease, albeit with different utilization profiles (range of prevalence 1.7-55.6%). Conclusion: To the best of our knowledge, this is the first study investigating the utilization profile of orphan drugs prescribed in a defined geographical area, and providing relevant information to monitor over time potential changes in the prevalence of these medications as well as in the health care decision making.

Tetramethylpyrazine Improves Monocrotaline-Induced Pulmonary Hypertension through the ROS/iNOS/PKG-1 Axis

Background

Tetramethylpyrazine (TMP), a potent anti-free radical and anti-inflammations substance, has been demonstrated to possess a direct vessel relaxation property. This study aimed to evaluate the effect of TMP treatment in pulmonary hypertension (PH) and test the hypothesis that TMP prevents or reverses the process of PH.

Methods

Rats (n = 36) injected with 50 mg/kg of monocrotaline (MCT) subcutaneously 4 weeks to develop PH were then randomized to TMP (5 mg/kg per day) for another 4 weeks. Hemodynamics was evaluated via the right ventricle. Pulmonary vessels structural remodeling and inflammation were examined by histologic and transmission electron microscopy observation. The expression of inducible nitric oxide synthase (iNOS) and cGMP-dependent protein kinases 1 (PKG-1) was detected by immunohistochemical staining and Western blot. Generation of reactive oxygen species (ROS) and antioxidation species was measured by biochemical analyses.

Results

MCT increased PH and right ventricle hypertrophy. TMP alleviated pulmonary arterial pressure elevation, leukocyte infiltration, and structural remodeling of pulmonary arterials induced by MCT successfully. TMP treatment significantly increased the PKG-1 expression and suppressed the iNOS expression. The activity of superoxide dismutase (SOD), glutathione peroxidase (GSH), and catalase (CAT) was significantly higher than control group, while malondialdehyde (MDA) levels were lower compared with MCT group.

Conclusion

TMP can suppress established MCT-induced PH through the ROS/iNOS/PKG axis. The underlying mechanisms may be associated with its anti-inflammatory, antioxidant, and antiproliferative properties in pulmonary arterial.

Baseline Ratio of Soluble Fas/FasL Predicts Onset of Pulmonary Hypertension in Elder Patients Undergoing Maintenance Hemodialysis: A Prospective Cohort Study

Background

Pulmonary hypertension (PH) is one of the most common complications associated with end-stage renal disease (ESRD). Though numerous risk factors have been founded, other risk factors remain unidentified, particularly in patients undergoing maintenance hemodialysis with elder age. Soluble Fas (sFas) and its ligand FasL (sFasL) have been reported in chronic renal disease patients; however, they have not been identified in the PH patients of elder hemodialysis patients. We aimed to determine the roles of sFas/sFasL in onset of PH in elder patients undergoing maintenance hemodialysis with ESRD.

Methods

Altogether, 163 patients aged 68.00 ± 10.51 years with ESRD who undergoing maintenance hemodialysis in a prospective cohort and were followed-up for a median of 5.5 years. They underwent echocardiography examinations, liver function assessments, residual renal function, and serum ion examinations, before and after dialysis. Furthermore, levels of sFas and sFasL at baseline had also been measured. We compared demographic data, echocardiographic parameters, liver function, ions, and residual renal function as well as serum sFas and sFasL between the PH and non-PH groups. These parameters were correlated with systolic pulmonary artery pressure (sPAP) using Spearman’s correlation. Moreover, univariate and adjusted logistic regression analyses have also been conducted.

Results

The incidence of PH in the elder dialysis patients was 39.1%. PH populations were demonstrated with significantly higher end-diastolic internal diameters of the left atrium, left ventricle, right ventricle (RV), and pulmonary artery, as well as the left ventricular posterior wall thickness (LVWP; all p < 0.05). A higher baseline serum sFas and sFasL levels have also been identified ( p < 0.001). They also showed lower fractional shortening and left ventricular ejection fraction (LVEF; p < 0.05). Following dialysis, the post-dialysis serum potassium concentration (K⁺) was significantly higher in the PH group ( p = 0.013). Furthermore, the adjusted regression identified that ratio of sFas/FasL (OR: 1.587, p = 0.004), RV (OR: 1.184, p = 0.014), LVPW (OR: 1.517, p = 0.007), and post-dialysis K⁺ (OR: 2.717, p = 0.040) was the independent risk factors for PH while LVEF (OR: 0.875, p = 0.040) protects patients from PH.

Conclusion

The baseline ratio of sFas/sFasL, RV, LVPW, and post-dialysis K⁺ was independent risk factors for PH onset, while LVEF was a protective factor for PH.

Spanish COPD Guidelines (GesEPOC) 2021: Updated Pharmacological treatment of stable COPD

The Spanish COPD Guidelines (GesEPOC) were first published in 2012, and since then have undergone a series of updates incorporating new evidence on the diagnosis and treatment of COPD. GesEPOC was drawn up in partnership with scientific societies involved in the treatment of COPD and the Spanish Patients' Forum. Their recommendations are based on an evaluation of the evidence using GRADE methodology, and a narrative description of the evidence in areas in which GRADE cannot be applied. In this article, we summarize the recommendations on the pharmacological treatment of stable COPD based on 9 PICO questions. COPD treatment is a 4-step process: 1) diagnosis, 2) determination of the risk level, 3) initial and subsequent inhaled therapy, and 4) identification and management of treatable traits. For the selection of inhaled therapy, high-risk patients are divided into 3 phenotypes: non-exacerbator, eosinophilic exacerbator, and non-eosinophilic exacerbator. Some treatable traits are general and should be investigated in all patients, such as smoking or inhalation technique, while others affect severe patients in particular, such as chronic hypoxemia and chronic bronchial infection. COPD treatment is based on long-acting bronchodilators with single agents or in combination, depending on the patient's risk level. Eosinophilic exacerbators must receive inhaled corticosteroids, while non-eosinophilic exacerbators require a more detailed evaluation to choose the best therapeutic option. The new GesEPOC also includes recommendations on the withdrawal of inhaled corticosteroids and on indications for alpha-1 antitrypsin treatment. GesEPOC offers a more individualized approach to COPD treatment tailored according to the clinical characteristics of patients and their level of complexity.

Mesenchymal stem cell-derived small extracellular vesicles in the treatment of human diseases: Progress and prospect

Mesenchymal stem cells (MSCs) are self-renewing, multipotent cells that could differentiate into multiple tissues. MSC-based therapy has become an attractive and promising strategy for treating human diseases through immune regulation and tissue repair. However, accumulating data have indicated that MSC-based therapeutic effects are mainly attributed to the properties of the MSC-sourced secretome, especially small extracellular vesicles (sEVs). sEVs are signaling vehicles in intercellular communication in normal or pathological conditions. sEVs contain natural contents, such as proteins, mRNA, and microRNAs, and transfer these functional contents to adjacent cells or distant cells through the circulatory system. MSC-sEVs have drawn much attention as attractive agents for treating multiple diseases. The properties of MSC-sEVs include stability in circulation, good biocompatibility, and low toxicity and immunogenicity. Moreover, emerging evidence has shown that MSC-sEVs have equal or even better treatment efficacies than MSCs in many kinds of disease. This review summarizes the current research efforts on the use of MSC-sEVs in the treatment of human diseases and the existing challenges in their application from lab to clinical practice that need to be considered.

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.

Metformin prevents the development of monocrotaline-induced pulmonary hypertension by decreasing serum levels of big endothelin-1

Pulmonary hypertension (PH) is a disease with poor prognosis, and it is characterized by the progressive elevation of pulmonary vascular resistance and pressure. Various factors are associated with the pathology of PH, including AMP-activated protein kinase (AMPK) deficiency. The present study aimed to evaluate the therapeutic effect of metformin, an AMPK activator, in a monocrotaline (MCT)-induced PH rat model. Rats were randomly divided into the following three groups: i) Saline-injected group (sham group); ii) monocrotaline (MCT)-injected group (PH group); iii) MCT-injected and metformin-treated group (MT group). Four weeks following MCT injection, cardiac ultrasonography, invasive hemodynamic measurements, measurement of serum levels of big endothelin-1 (big ET-1) and histological analysis were performed to evaluate the effect of metformin treatment in PH. Pulmonary arterial pressure and serum big ET-1 concentrations were reduced in the MT group compared with the PH group. Medial wall thickness and wall area of the pulmonary arterioles in the MT group were decreased compared with the PH group. Comparing the right heart functional parameters among groups revealed that the acceleration time/ejection time ratio improved in the MT group compared with the PH group. Thus, the present study demonstrated the efficacy of metformin in an MCT-induced PH rat model and suggested that metformin may be a valuable, potential novel therapeutic for the treatment of PH.

Resistance training prevents right ventricle hypertrophy in rats exposed to secondhand cigarette smoke

Exposure to secondhand cigarette smoke is associated with the development of diverse diseases. Resistance training has been considered one of the most useful tools for patients with pulmonary disease, improving their quality of life. This study aimed to evaluate the effect of resistance training (RT) on the prevention of thickening of the right ventricle wall of rats exposed to secondhand cigarette smoke. Thirty-two Wistar rats were divided into four groups: Control (C), Smoker (S), Exercised (E) and Exercised Smoker (ES). The smoker groups were exposed to the smoke of four cigarettes for 30 min, twice daily, five days a week, for 16 weeks. The exercised groups climbed on a vertical ladder with progressive load, once a day, five days a week, for 16 weeks. The heart, trachea, lung, liver and gastrocnemius muscle were removed for histopathological analysis. Pulmonary emphysema (S and ES vs C and E, P < 0.0001) and pulmonary artery thickness enlargement (S vs C and E, P = 0.003, ES vs C, P = 0.003) were detected in the smoking groups. There was an increase in the right ventricle thickness in the S group compared with all other groups (P < 0.0001). An increase in resident macrophages in the liver was detected in both smoking groups compared with the C group (P = 0.002). Additionally, a relevant reduction of the diameter of the muscle fibers was detected only in ES compared with the C, S and E groups (P = 0.0002), impairing, at least in part, the muscle mass in exercised smoking rats. Therefore, it was concluded that resistance training prevented the increase of thickness of the right ventricle in rats exposed to secondhand cigarette smoke, but it may be not so beneficial for the skeletal muscle of smoking rats.

Double-stranded RNA and Toll-like receptor activation: a novel mechanism for blood pressure regulation

Toll-like receptors (TLRs), such as TLR4 and 9, recognize pathogen-associated molecular pattern (PAMPs) and danger-associated molecular patterns (DAMPs) and are associated with increased blood pressure (BP). TLR3, residing in the endosomal compartment, is activated by viral double-stranded RNA (dsRNA) leading to activation of TIR receptor domain-containing adaptor inducing IFN-β (TRIF) dependent pathway. Besides foreign pathogens, the immune system responds to endogenous markers of cellular damage such as mitochondrial dsRNA (mtdsRNA). New evidence has shown a link between dsRNA and increased BP. Moreover, TLR3 activation during pregnancy was demonstrated to develop preeclampsia-like symptoms in both rats and mice. Hence, we hypothesize that the dsRNA derived from viral nucleic acids or cellular damage (mtdsRNA) will increase the inflammatory state through activation of TLR3, contributing to vascular dysfunction and increased BP. Therefore, inhibition of TLR3 could be a therapeutic target for the treatment of hypertension with potential improvement in vascular reactivity and consequently, a decrease in BP.

The era of clinical application of gene diagnosis in cardiovascular diseases is coming

Gene diagnosis refers to the use of genetic testing in the diagnosis of inheritable conditions, which has gradually been applied in clinical practice with the completion of the gene sequencing efforts of the Human Genome Project and the advancement of gene detection technology. In the specialty field of cardiology, monogenic cardiovascular diseases are defined as monogenic inherited diseases with cardiovascular damage as the only phenotype, or accompanied by cardiovascular damage. Although the incidence of such diseases is relatively low, in the country of China with its vast population of 1.33 billion, the sheer volume of patients with monogenic cardiovascular diseases is alarming. With early onset, severe symptoms, and poor prognosis, delays in diagnosis and treatment of monogenic cardiovascular diseases often have serious consequences. Gene testing is perfectly suited for early diagnosis of monogenic cardiovascular diseases, especially for "pre-symptomatic" diagnosis. In this article, we generally review the characteristics of common monogenic cardiovascular diseases, summarize the progress of the standardized application of gene testing technology in clinical practice, describe the applicable population and condition of genetic testing for different monogenic cardiovascular diseases, analyze the practicality of genetic diagnosis of these inheritable conditions, and provide guidance on identifying suitable candidates for gene diagnosis. In conclusion, gene diagnosis provides new insights into the way physicians diagnose diseases, and is well-positioned to guide clinical decision making and treatment, especially in cardiology.

Idiopathic Pulmonary Fibrosis: Epidemiology, Natural History, Phenotypes

Idiopathic pulmonary fibrosis (IPF) is the most common of the idiopathic interstitial pneumonias. It is characterized by a chronic, progressive, fibrotic interstitial lung disease of unknown cause that occurs primarily in older adults. Its prevalence and incidence have appeared to be increasing over the last decades. Despite its unknown nature, several genetic and environmental factors have been associated with IPF. Moreover, its natural history is variable, but could change depending on the currently suggested phenotypes: rapidly progressive IPF, familial, combined pulmonary fibrosis and emphysema, pulmonary hypertension, and that associated with connective tissue diseases. Early recognition and accurate staging are likely to improve outcomes and induce a prompt initiation of antifibrotics therapy. Treatment is expected to be more effective in the early stages of the disease, while developments in treatment aim to improve the current median survival of 3⁻4 years after diagnosis.

Methods of Pharmacological Treatment of Chronic Thromboembolic Pulmonary Hypertension Current Approaches to the Patients Management

In this paper we have discussed epidemiology, pathogenesis, and approaches to treatment of chronic thromboembolic pulmonary hypertension (CTEPH). CTEPH is a unique potentially curable form of pulmonary hypertension. The gold standard of CTEPH treatment is pulmonary thromboendarterectomy. However, about 40% of patients with CTEPH are inoperable due to distal surgically inaccessible lesions of the pulmonary vasculature, severe hemodynamic impairments, or other contraindications. In addition, nearly half of patients have persistent or recurrent pulmonary hypertension following surgery. Current guidelines support the use of pharmacotherapy in these patients. In the article we have presented results of main clinical studies of targeted drugs therapy (endothelin receptor antagonists, prostanoids, phosphodiesterase type 5 inhibitors, soluble guanylate cyclase stimulators) of patients with CTEPH. The only drug that has demonstrated robust clinical efficacy in terms of improvment hemodynamic parameters, exercise capacity and patients' quality of life is the stimulator of the soluble guanylate cyclase riociguat. The efficacy and safety of riociguat have been investigated in short-term and long-term studies with follow-up up to 6 years. Results of these studies have constituted the basis forits approval by the regulatory authorities of more than 50 countries for the treatment of inoperable CTEPH and persistent or recurrent CTEPH after pulmonary thromboendarterectomy. In the European Union, USA and many other countries, riociguat is the only pharmacological agent approved for these indications.