An Infant with High-Output Heart Failure and Pulmonary Hypertension Resulting from a Giant Cutaneous Hemangioma.

We present the clinical course of an 8-month-old infant with a giant cutaneous hemangioma resulting in high-output heart failure and pulmonary hypertension. The lesion was successfully embolized and excised, with rapid resolution of heart failure and improvement in pulmonary hypertension.

Pulmonary hypertension across the spectrum of left heart and lung disease.

AIMS: Patients with pulmonary hypertension (PH) are grouped based upon clinical and haemodynamic characteristics. Groups 2 (G2, left heart disease [LHD]) and 3 (G3, lung disease or hypoxaemia) are most common. Many patients display overlapping characteristics of heart and lung disease (G2-3), but this group is not well-characterized. METHODS AND RESULTS: Patients with PH enrolled in the prospective, NHLBI-sponsored PVDOMICS network underwent intensive clinical, biomarker, imaging, gas exchange and exercise phenotyping. Patients with pure G2, pure G3, or overlapping G2-3 PH were compared across multiple phenotypic domains. Of all patients with predominant G2 (n = 136), 66 (49%) were deemed to have secondary lung disease/hypoxaemia contributors (G2/3), and of all patients categorized as predominant G3 (n = 172), 41 (24%) were judged to have a component of secondary LHD (G3/2), such that 107 had G2-3 (combined G2/3 and G3/2). As compared with G3, patients with G2 and G2-3 were more obese and had greater prevalence of hypertension, atrial fibrillation, and coronary disease. Patients with G2 and G2-3 were more anaemic, with poorer kidney function, more cardiac dysfunction, and higher N-terminal pro-B-type natriuretic peptide than G3. Lung diffusion was more impaired in G3 and G2-3, but commonly abnormal even in G2. Exercise capacity was severely and similarly impaired across all groups, with no differences in 6-min walk distance or peak oxygen consumption, and pulmonary vasoreactivity to nitric oxide did not differ. In a multivariable Cox regression model, patients with G2 had lower risk of death or transplant compared with G3 (hazard ratio [HR] 0.51, 95% confidence interval [CI] 0.30-0.86), and patients with G2-3 also displayed lower risk compared with G3 (HR 0.57, 95% CI 0.38-0.86). CONCLUSIONS: Overlap is common in patients with a pulmonary or cardiac basis for PH. While lung structure/function is clearly more impaired in G3 and G2-3 than G2, pulmonary abnormalities are common in G2, even when clinically judged as isolated LHD. Further study is required to identify optimal systematic evaluations to guide therapeutic innovation for PH associated with combined heart and lung disease. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov NCT02980887.

Role of transient receptor potential channels in the regulation of vascular tone.

Vascular tone is a major element in the control of hemodynamics. Transient receptor potential (TRP) channels conducting monovalent and/or divalent cations(e.g. Na+ and Ca2+) are expressed in the vasculature. Accumulating evidence suggests that TRP channels participate in regulating vascular tone by regulating intracellular Ca2+ signaling in both vascular smooth muscle cells (VSMCs) and endothelial cells (ECs). Aberrant expression/function of TRP channels in the vasculature is associated with vascular dysfunction in systemic/pulmonary hypertension and metabolic syndromes. This review intends to summarize our current knowledge of TRP-mediated regulation of vascular tone in both physiological and pathophysiological conditions and to discuss potential therapeutic approaches to tackle abnormal vascular tone due to TRP dysfunction.

The management pattern and outcomes of chronic thromboembolic pulmonary hypertension: rationale and design for a Chinese real-world study.

BACKGROUND: Chronic thromboembolic pulmonary hypertension (CTEPH) is a progressive pulmonary vascular disorder with substantial morbidity and mortality, also a disease underdiagnosed and undertreated. It is potentially curable by pulmonary endarterectomy (PEA) in patients with surgically accessible thrombi. Balloon pulmonary angioplasty (BPA) and targeted medical therapy are options for patients with distal lesions or persistent/recurrent pulmonary hypertension after PEA. There is an urgent need to increase the awareness of CTEPH. Qualified CTEPH centers are still quite limited. Baseline characteristics, management pattern and clinical outcome of CTEPH in China needs to be reported. METHODS AND DESIGN: The CHinese reAl-world study to iNvestigate the manaGEment pattern and outcomes of chronic thromboembolic pulmonary hypertension (CHANGE) study is designed to provide the multimodality treatment pattern and clinical outcomes of CTEPH in China. Consecutive patients who are ≥ 14 year-old and diagnosed with CTEPH are enrolled. The diagnosis of CTEPH is confirmed in right heart catheterization and imaging examinations. The multimodality therapeutic strategy, which consists of PEA, BPA and targeted medical therapy, is made by a multidisciplinary team. The blood sample and tissue from PEA are stored in the central biobank for further research. The patients receive regular follow-up every 3 or 6 months for at least 3 years. The primary outcomes include all-cause mortality and changes in functional and hemodynamic parameters from baseline. The secondary outcomes include the proportion of patients experiencing lung transplantation, the proportion of patients experiencing heart and lung transplantation, and changes in health-related quality of life. Up to 31 December 2023, the study has enrolled 1500 eligible patients from 18 expert centers. CONCLUSIONS: As a real-world study, the CHANGE study is expected to increase our understanding of CTEPH, and to fill the gap between guidelines and the clinical practice in the diagnosis, assessment and treatment of patients with CTEPH. REGISTRATION NUMBER IN CLINICALTRIALS.GOV: NCT05311072.

Multimodal Assessment and Intramodal Comparison of Imaging Techniques for Pediatric Pulmonary Vein Stenosis with Pulmonary Hypertension.

Pulmonary vein stenosis (PVS) is a rare, serious, and progressive disease in the pediatric population. Evaluation is complex and involves multimodality imaging. Diagnosis is important as early treatment to prevent progressive pulmonary hypertension and right ventricular dysfunction is essential. Adult studies have shown good correlation between various imaging modalities; however, there are limited data in children. This is a single-center retrospective pilot study to determine the reliability of measurement of pulmonary vein stenosis and pulmonary hypertension across different imaging modalities-computed tomography angiography (CTA), echocardiography (echo), lung perfusion scan (LPS), and cardiac catheterization (cath). PVS was defined as > 2 mmHg by echo and cath and/or 50% reduction in diameter by CTA. Patients had to have an echo, CTA and cath performed within a 1-month timeframe of one another to be included in the study, with LPS data included if testing was completed at initial evaluation. Fifteen total patients were enrolled; 87% were categorized as primary PVS; a condition not directly related to direct injury or prior surgical intervention. Twenty-seven total stenotic pulmonary veins were identified (mean 1.8, range 1-4). CTA had a slightly better agreement with cath than echo in identifying PVS in different vein locations except in the LLPV. Additionally, echo and CTA had excellent sensitivity (91%) and specificity (100%) compared to cath for diagnosis of PH. We conclude that non-invasive imaging of echo and CTA has an acceptable correlation to cardiac catheterization for screening and initial evaluation of PVS and PH, as directly related to PVS, in pediatrics.

Notch ratio in pulmonary flow predicts long-term survival after pulmonary endarterectomy for chronic thromboembolic pulmonary hypertension.

BACKGROUND: Assessment of the pattern of the RV outflow tract Doppler provides insights into the hemodynamics of chronic thromboembolic pulmonary hypertension (CTEPH). We studied whether pre-operative assessment of timing of the pulmonary flow systolic notch by Doppler echocardiography is associated with long-term survival after pulmonary endarterectomy (PEA) for CTEPH. METHODS: Fifty-nine out of 61 consecutive CETPH patients (mean age 53 ± 14 years, 34% male) whom underwent PEA between June 2002 and June 2005 were studied. Clinical, echocardiographic and hemodynamic variables were assessed pre-operatively and repeat echocardiography was performed 3 months after PEA. Notch ratio (NR) was assessed with pulsed Doppler and calculated as the time from onset of pulmonary flow until notch divided by the time from notch until end of pulmonary flow. Long-term follow-up was obtained between May 2021 and February 2022. RESULTS: Pre-operative mean pulmonary artery pressure (mPAP) was 45 ± 15 mmHg and pulmonary vascular resistance (PVR) was 646 ± 454 dynes.s.cm-5. Echocardiography before PEA showed that 7 patients had no notch, 33 had a NR < 1.0 and 19 had a NR > 1.0. Three months after PEA, echocardiography revealed a significant decrease in sPAP in long-term survivors with a NR < 1.0 and a NR > 1.0, while a significant increase in TAPSE/sPAP was only observed in the NR < 1.0 group. Mean long-term clinical follow-up was 14 ± 6 years. NR was significantly different between survivors and non-survivors (0.73 ± 0.25 vs. 1.1 ± 0.44, p < 0.001) but no significant differences were observed in mPAP or PVR. Long-term survival at 14 years was significantly better in patients with a NR < 1.0 compared to patients with a NR > 1.0 (83% vs. 37%, p = < 0.001). CONCLUSION: Pre-operative assessment of NR is a predictor of long-term survival in CTEPH patients undergoing PEA, with low mortality risk in patients with NR < 1.0. Long-term survivors with a NR < 1.0 and NR > 1.0 had a significant decrease in sPAP after PEA. However, the TAPSE/sPAP only significantly increased in the NR < 1.0 group. In the NR < 1.0 group, the 6-min walk test increased significantly between pre-operative and at 1-year post-operative follow-up. NR is a simple echocardiographic parameter that can be used in clinical decision-making for PEA.

Anomalous Bronchial Artery Origin - Canary in the Coal Mine - For Diagnosing Chronic Thromboembolic Pulmonary Hypertension.

Anomalous bronchial artery origins may have clinical implications beyond their anatomical curiosity. In this case, identification of such an anomaly led to the diagnosis of chronic thromboembolic pulmonary hypertension (CTEPH). A 49-year-old male with a history of recurrent deep vein thrombosis (DVT) and pulmonary embolism (PE) on anticoagulation presented with chest pain and shortness of breath. Laboratory analysis was remarkable for a troponin peak of 14.74 ng/ml, a brain natriuretic peptide level of 602 pg/ml and a D-dimer level of 0.62 µg/ml. Electrocardiogram showed non-specific ST elevation in the anterolateral and inferior leads. Computed tomography angiography (CTA) of the chest was positive for PE involving the right lower lobe pulmonary arterial tree. Echocardiogram showed reduced left ventricular function (ejection fraction 38%) and akinesis of the antero-apical and infero-apical segments. Cardiac catheterization revealed non-obstructive coronary arteries, and an anomalous origin of a right bronchial artery from the right coronary artery. The right bronchial hypertrophied as it supplied collateral flow to the occluded right pulmonary artery. This anomaly and the patient's history of multiple DVT/PEs while on therapeutic levels of warfarin with near normal D-dimer levels raised suspicion for a false positive PE. Pulmonary angiogram revealed chronic occlusion in branches of the right pulmonary artery, mean pulmonary artery pressure of 36 mmHg and no acute thrombus. Ventilation-perfusion scan confirmed the diagnosis of CTEPH. The patient underwent successful pulmonary thromboendarterectomy and subsequently had normalization of mean pulmonary artery pressure. This case underscores the importance of a comprehensive diagnostic approach, and consideration of alternative explanations for imaging findings, that unveiled the diagnosis of a complex and life-threatening condition such as CTEPH. LEARNING POINTS: This case underscores the diagnostic significance of identifying anomalous bronchial artery origin which played a crucial role in the diagnosis of the underlying chronic thromboembolic pulmonary hypertension (CTEPH).It is important to understand the limitations of computed tomography angiography (CTA) chest for diagnosis of CTEPH.

A Lifelike guided journey through the pathophysiology of pulmonary hypertension-from measured metabolites to the mechanism of action of drugs.

Introduction: Pulmonary hypertension (PH) is a pathological condition that affects approximately 1% of the population. The prognosis for many patients is poor, even after treatment. Our knowledge about the pathophysiological mechanisms that cause or are involved in the progression of PH is incomplete. Additionally, the mechanism of action of many drugs used to treat pulmonary hypertension, including sotatercept, requires elucidation. Methods: Using our graph-powered knowledge mining software Lifelike in combination with a very small patient metabolite data set, we demonstrate how we derive detailed mechanistic hypotheses on the mechanisms of PH pathophysiology and clinical drugs. Results: In PH patients, the concentration of hypoxanthine, 12(S)-HETE, glutamic acid, and sphingosine 1 phosphate is significantly higher, while the concentration of L-arginine and L-histidine is lower than in healthy controls. Using the graph-based data analysis, gene ontology, and semantic association capabilities of Lifelike, led us to connect the differentially expressed metabolites with G-protein signaling and SRC. Then, we associated SRC with IL6 signaling. Subsequently, we found associations that connect SRC, and IL6 to activin and BMP signaling. Lastly, we analyzed the mechanisms of action of several existing and novel pharmacological treatments for PH. Lifelike elucidated the interplay between G-protein, IL6, activin, and BMP signaling. Those pathways regulate hallmark pathophysiological processes of PH, including vasoconstriction, endothelial barrier function, cell proliferation, and apoptosis. Discussion: The results highlight the importance of SRC, ERK1, AKT, and MLC activity in PH. The molecular pathways affected by existing and novel treatments for PH also converge on these molecules. Importantly, sotatercept affects SRC, ERK1, AKT, and MLC simultaneously. The present study shows the power of mining knowledge graphs using Lifelike's diverse set of data analytics functionalities for developing knowledge-driven hypotheses on PH pathophysiological and drug mechanisms and their interactions. We believe that Lifelike and our presented approach will be valuable for future mechanistic studies of PH, other diseases, and drugs.

Assessing the correlation between the degree of tricuspid regurgitation and pulmonary hypertension: A comprehensive study.

OBJECTIVES: To evaluate the relationship between severity of tricuspid regurgitation (TR) and pulmonary hypertension. METHODS: Cross-sectional study of 118 patients with pulmonary hypertension was carried out at a single center in Jeddah, Saudi Arabia, between 2018-2021. Patients who had pulmonary or tricuspid valves organic diseases, previously undergone tricuspid or pulmonary valve surgeries, had permanent pacemakers or critically ill were excluded. RESULTS: A high proportion of patients were women (n=100, 85%) and obese (n=57, 48%). Patients with more than mild TR had higher systolic pulmonary artery pressure (sPAP) than those with trivial or mild regurgitation (p<0.001). There was a significant association between severity of TR (p<0.001) and right chambers size (p=0.001). Furthermore, pulmonary artery pressure (PAP) was significantly higher in patients with mild right ventricular impairment (p=0.001). CONCLUSION: Increase in degree of TR and right atrial size were predictors of elevated sPAP. Our findings highlight the interplay among TR, right heart size, ventricular function, and PAP. Understanding these associations can aid in risk stratification, monitoring disease progression, and potentially guiding treatment in those patients.

Crocin's role in modulating MMP2/TIMP1 and mitigating hypoxia-induced pulmonary hypertension in mice.

To explore the molecular pathogenesis of pulmonary arterial hypertension (PAH) and identify potential therapeutic targets, we performed transcriptome sequencing of lung tissue from mice with hypoxia-induced pulmonary hypertension. Our Gene Ontology analysis revealed that "extracellular matrix organization" ranked high in the biological process category, and matrix metallopeptidases (MMPs) and other proteases also played important roles in it. Moreover, compared with those in the normoxia group, we confirmed that MMPs expression was upregulated in the hypoxia group, while the hub gene Timp1 was downregulated. Crocin, a natural MMP inhibitor, was found to reduce inflammation, decrease MMPs levels, increase Timp1 expression levels, and attenuate hypoxia-induced pulmonary hypertension in mice. In addition, analysis of the cell distribution of MMPs and Timp1 in the human lung cell atlas using single-cell RNAseq datasets revealed that MMPs and Timp1 are mainly expressed in a population of fibroblasts. Moreover, in vitro experiments revealed that crocin significantly inhibited myofibroblast proliferation, migration, and extracellular matrix deposition. Furthermore, we demonstrated that crocin inhibited TGF-ß1-induced fibroblast activation and regulated the pulmonary arterial fibroblast MMP2/TIMP1 balance by inhibiting the TGF-ß1/Smad3 signaling pathway. In summary, our results indicate that crocin attenuates hypoxia-induced pulmonary hypertension in mice by inhibiting TGF-ß1-induced myofibroblast activation.

Oral Prostacyclin Pathway Agents Used in PAH: A Targeted Literature Review.

Purpose: Pulmonary arterial hypertension (PAH) is a rare and progressive pulmonary vascular disease that can result in right heart failure and death. Oral prostacyclins play an important role in the management of intermediate-low risk PAH. This targeted literature review (TLR) aimed to identify and compare evidence supporting use of oral prostacyclin pathway agents (PPAs: selexipag and oral treprostinil) in intermediate-low risk PAH. Methods: A targeted literature review was conducted. Literature databases (MEDLINE, Embase, and Cochrane reviews) were searched for studies describing clinical practice and treatment outcomes for oral treprostinil and selexipag globally, published in English (2012 to 2022). Electronic searches were supplemented by manual-searches of targeted conferences (2020 to 2022), and reference lists of identified publications were reviewed. One reviewer assessed studies for eligibility. Results: In total, 95 publications met inclusion criteria: 47 full-text articles (selexipag n = 22; oral treprostinil n = 16; selexipag and oral treprostinil n = 9) and 48 conference materials. Selexipag and oral treprostinil target the prostacyclin pathway differently; their label-supporting trials had different primary endpoints (disease progression and hospitalization vs exercise capacity and disease progression), differing baseline therapy (0, 1 or 2 vs 0 or 1 baseline treatments), titration duration and dosing (personalized dose capped at 1600 ug twice daily (BID) vs increasing doses over time with no maximum dose), respectively. While both oral PPAs have demonstrated reduced risk of disease progression, only selexipag showed reduction in hospitalization rates. Oral PPAs have been shown to reduce healthcare costs in real-world clinical practice. This difference is reflected in labeled indications. Conclusion: Given differences in trial- and real-world outcomes, number of prior therapies, and dosing, personalizing the choice of oral PPA is critical to maximizing the benefit for individual patients.

PAH is a condition that causes heart failure. It is important to take medicines to slow down this process. For people with early disease, there are some medicines that can be taken as a tablet rather than as an injection to slow down disease progression. The differences between two of the tablet options ­ selexipag and oral treprostinil, are unclear. We reviewed publications describing how, when and why these medicines are used and how well they work, to improve our understanding of the value of these medicines to people with PAH.

SGLT2 inhibitors as a potential therapeutic option for pulmonary hypertension: mechanisms and clinical perspectives.

Pulmonary arterial hypertension (PAH), one subtype of pulmonary hypertension (PH), is a life-threatening condition characterized by pulmonary arterial remodeling, elevated pulmonary vascular resistance, and blood pressure in the pulmonary arteries, leading to right heart failure and increased mortality. The disease is marked by endothelial dysfunction, vasoconstriction, and vascular remodeling. The role of Sodium-Glucose Co-Transporter-2 (SGLT2) inhibitors, a class of medications originally developed for diabetes management, is increasingly being explored in the context of cardiovascular diseases, including PAH, due to their potential to modulate these pathophysiological processes. In this review, we systematically examine the burgeoning evidence from both basic and clinical studies that describe the effects of SGLT2 inhibitors on cardiovascular health, with a special emphasis on PAH. By delving into the complex interactions between these drugs and the potential pathobiology that underpins PH, this study seeks to uncover the mechanistic underpinnings that could justify the use of SGLT2 inhibitors as a novel therapeutic approach for PAH. We collate findings that illustrate how SGLT2 inhibitors may influence the normal function of pulmonary arteries, possibly alleviating the pathological hallmarks of PAH such as inflammation, oxidative stress, aberrant cellular proliferation, and so on. Our review thereby outlines a potential paradigm shift in PAH management, suggesting that these inhibitors could play a crucial role in modulating the disease's progression by targeting the potential dysfunctions that drive it. This comprehensive synthesis of existing research underscores the imperative need for further clinical trials to validate the efficacy of SGLT2 inhibitors in PAH and to integrate them into the therapeutic agents used against this challenging disease.

Fetal ductal constriction caused by SSRI: A case report.

A 31-week fetus was diagnosed with premature ductal constriction due to maternal treatment with sertraline. An emergent Cesarean section was performed at 32 gestational weeks. The baby was born in a severely depressed condition, with supra-systemic pulmonary hypertension, requiring intubation, mechanical ventilation, and milrinone infusion. The patient's condition improved rapidly, allowing weaning from the ventilator and the inodilator therapy. The baby was discharged home at 38 weeks postmenstrual age, in good general condition, without any signs of pulmonary hypertension, requiring no respiratory support. The echo examinations on the first and third months after birth were normal.

A comprehensive study on machine learning models combining with oversampling for bronchopulmonary dysplasia-associated pulmonary hypertension in very preterm infants.

BACKGROUND: Bronchopulmonary dysplasia-associated pulmonary hypertension (BPD-PH) remains a devastating clinical complication seriously affecting the therapeutic outcome of preterm infants. Hence, early prevention and timely diagnosis prior to pathological change is the key to reducing morbidity and improving prognosis. Our primary objective is to utilize machine learning techniques to build predictive models that could accurately identify BPD infants at risk of developing PH. METHODS: The data utilized in this study were collected from neonatology departments of four tertiary-level hospitals in China. To address the issue of imbalanced data, oversampling algorithms synthetic minority over-sampling technique (SMOTE) was applied to improve the model. RESULTS: Seven hundred sixty one clinical records were collected in our study. Following data pre-processing and feature selection, 5 of the 46 features were used to build models, including duration of invasive respiratory support (day), the severity of BPD, ventilator-associated pneumonia, pulmonary hemorrhage, and early-onset PH. Four machine learning models were applied to predictive learning, and after comprehensive selection a model was ultimately selected. The model achieved 93.8% sensitivity, 85.0% accuracy, and 0.933 AUC. A score of the logistic regression formula greater than 0 was identified as a warning sign of BPD-PH. CONCLUSIONS: We comprehensively compared different machine learning models and ultimately obtained a good prognosis model which was sufficient to support pediatric clinicians to make early diagnosis and formulate a better treatment plan for pediatric patients with BPD-PH.

Selexipag Dosing Strategies for Pediatric Patients with Pulmonary Arterial Hypertension.

This retrospective chart review of patients less than 18 years old with pulmonary arterial hypertension (PAH) receiving selexipag was conducted to describe selexipag dosing practices, impact on concomitant PAH therapies, and the safety and efficacy of selexipag. Twenty-seven patients aged 1-17 years started a median dose of oral selexipag 100 µg twice daily. Therapy was increased by a median of 100 µg twice daily every 6 days to a maximally tolerated median dose of 800 µg twice daily. All 24 patients on another prostacyclin derivative were able to discontinue therapy at their maximum tolerated selexipag dose; other concomitant PAH therapies did not change. Changes in echocardiogram data and 6-MWT results were variable. No patients discontinued selexipag; four patients received decreased doses due to flushing (n = 1), drug interactions (n = 2), or increased frequency of nose bleeds (n = 1).

The acute effect of inhaled nitric oxide on the exercise capacity of patients with advanced interstitial lung disease: a randomized controlled trial.

BACKGROUND: Inhaled nitric oxide (iNO) selectively acts on the pulmonary vasculature of ventilated lung tissue by reducing pulmonary vascular resistance and intrapulmonary shunt. This effect may reduce ventilation/perfusion mismatch and decrease pulmonary hypertension in patients with interstitial lung disease. METHODS: In a prospective, single-blinded, randomized, placebo-controlled trial, participants with advanced interstitial lung disease, underwent two separate six-minute walk tests (6MWT): one with iNO and the other with a placebo. The primary outcome measured the difference in meters between the distances covered in the two tests. Secondary outcomes included oxygen saturation levels, distance-saturation product, and Borg dyspnea score. A predefined subgroup analysis was conducted for patients with pulmonary hypertension. RESULTS: Overall, 44 patients were included in the final analysis. The 6MWT distance was similar for iNO treatment and placebo, median 362 m (IQR 265-409) vs 371 m (IQR 250-407), respectively (p = 0.29). Subgroup analysis for patients with pulmonary hypertension showed no difference in 6MWT distance with iNO and placebo, median 339 (256-402) vs 332 (238-403) for the iNO and placebo tests respectively (P=0.50). No correlation was observed between mean pulmonary artery pressure values and the change in 6MWT distance with iNO versus placebo (spearman correlation Coefficient 0.24, P=0.33). CONCLUSION: In patients with advanced interstitial lung disease, both with and without concurrent pulmonary hypertension, the administration of inhaled nitric oxide failed to elicit beneficial effects on the six-minute walk distance and oxygen saturation. The use of inhaled NO was found to be safe and did not lead to any serious side effects. TRIAL REGISTRATION: (NCT03873298, MOH_2018-04-24_002331).

Single cell transcriptomic analyses reveal diverse and dynamic changes of distinct populations of lung interstitial macrophages in hypoxia-induced pulmonary hypertension.

Introduction: Hypoxia is a common pathological driver contributing to various forms of pulmonary vascular diseases leading to pulmonary hypertension (PH). Pulmonary interstitial macrophages (IMs) play pivotal roles in immune and vascular dysfunction, leading to inflammation, abnormal remodeling, and fibrosis in PH. However, IMs' response to hypoxia and their role in PH progression remain largely unknown. We utilized a murine model of hypoxia-induced PH to investigate the repertoire and functional profiles of IMs in response to acute and prolonged hypoxia, aiming to elucidate their contributions to PH development. Methods: We conducted single-cell transcriptomic analyses to characterize the repertoire and functional profiles of murine pulmonary IMs following exposure to hypobaric hypoxia for varying durations (0, 1, 3, 7, and 21 days). Hallmark pathways from the mouse Molecular Signatures Database were utilized to characterize the molecular function of the IM subpopulation in response to hypoxia. Results: Our analysis revealed an early acute inflammatory phase during acute hypoxia exposure (Days 1-3), which was resolved by Day 7, followed by a pro-remodeling phase during prolonged hypoxia (Days 7-21). These phases were marked by distinct subpopulations of IMs: MHCIIhiCCR2+EAR2+ cells characterized the acute inflammatory phase, while TLF+VCAM1hi cells dominated the pro-remodeling phase. The acute inflammatory phase exhibited enrichment in interferon-gamma, IL-2, and IL-6 pathways, while the pro-remodeling phase showed dysregulated chemokine production, hemoglobin clearance, and tissue repair profiles, along with activation of distinct complement pathways. Discussion: Our findings demonstrate the existence of distinct populations of pulmonary interstitial macrophages corresponding to acute and prolonged hypoxia exposure, pivotal in regulating the inflammatory and remodeling phases of PH pathogenesis. This understanding offers potential avenues for targeted interventions, tailored to specific populations and distinct phases of the disease. Moreover, further identification of triggers for pro-remodeling IMs holds promise in unveiling novel therapeutic strategies for pulmonary hypertension.

Prevalence of Pulmonary Hypertension in Liver Cirrhosis Patients: A Cross-Sectional Analytical Study.

BACKGROUND: Liver cirrhosis (LC) is a common complication of chronic liver disease. Its prevalence has increased markedly over the last few years. With liver cirrhosis comes cardiovascular morbidity and mortality. It is important that the detection of the abnormalities by echocardiography be given priority, as this can change the clinical outcome of these patients with cardiovascular abnormalities in liver cirrhosis. AIM: This study aims to determine the prevalence of pulmonary hypertension in LC patients. METHODS AND MATERIALS: A cross-sectional analytical study was carried out at JUTH (Jos University Teaching Hospital) over a period of one year. We recruited 210 adult patients with liver cirrhosis from the gastroenterology clinic and wards for this study. Data from these patients were collected with questionnaires administered by the interviewer and analysed using SPSS 23 statistical software (IBM Corp., Armonk, NY). The data obtained are presented in tables and charts. Categorical variables were expressed as proportions and frequencies, while continuous data were expressed as the median, mean, and standard deviation. RESULTS: Pulmonary hypertension was found in 30.5% of the participants, with mild pulmonary hypertension being the most common. No one had severe pulmonary hypertension. There was an increased risk of developing pulmonary hypertension in patients with coughs, easy fatigability, bilateral leg swelling, abdominal swelling, and ascites (P<0.05). CONCLUSION: The result showed that there is a high prevalence of pulmonary hypertension in patients with liver cirrhosis.