Pulmonary artery stent thrombosis and symptomatic pulmonary hypertension following COVID-19 infection in Alagille patient:A case report

BACKGROUND Alagille syndrome is a multisystem disease that results in various vascular anomalies,commonly involving the cardiac and pulmonary systems.To the best of our knowledge,there is no literature regarding the cardiovascular outcomes of these patients in association with coronavirus disease 2019(COVID-19).CASE SUMMARY A 34-year-old woman with a history of Alagille syndrome who underwent successful atrial septal defect with partial anomalous pulmonary veins and patent ductus arteriosus repair,as well as left pulmonary artery catheterization and stenting in childhood due to pulmonary stenosis.The patient was without any respiratory symptoms and was a dancer prior to contracting COVID-19.Several weeks after her COVID-19 infection,she developed left pulmonary artery stent thrombosis and subsequent symptomatic pulmonary hypertension.A treatment strategy of anticoagulation alongside pharmacological agents for pulmonary hypertension for 3 months followed by balloon pulmonary artery angioplasty to reopen the stenosis was unsuccessful.CONCLUSION In the era of COVID-19,patients with pulmonary vascular malformations and endovascular stents are at an increased risk for chronic thromboembolic disease.Patients may benefit from prophylactic antiplatelet or anticoagulation therapy.Stent thrombosis is a devastating phenomenon and should be treated urgently and aggressively with balloon pulmonary angioplasty,and/or a thrombolytic agent.

Rapid improvement in postpartum pulmonary hypertension associated with hereditary hemorrhagic telangiectasia: A case report and review of literature

BACKGROUND Postpartum pulmonary arterial hypertension(PAH)complicated with hereditary hemorrhagic telangiectasia(HHT)is a rare condition.Diagnosing and treating PAH in patients with HHT can be challenging.To the best of our knowledge,no previous reports have investigated the efficacy of pulmonary vasodilators in improving hemodynamics in postpartum patients with this disease.CASE SUMMARY In this paper,we report a postpartum case of HHT combined with PAH,pre-senting with worsening dyspnea.Genetic testing revealed that the patient carried a heterozygous variant of activin receptor-like kinase 1.The patient received various treatments,including diuretics,anticoagulants,sildenafil,macitentan,inhalation of nitric oxide,and iloprost.Changes in PaO2/FiO2,pulmonary artery systolic pressure as assessed by echocardiography,and N-terminus pro-brain natriuretic peptide levels suggested that,except for iloprost inhalation,the other treatments appeared to have limited efficacy.CONCLUSION To our knowledge,this is the first report on efficacy of pulmonary vasodilators in postpartum patients with HHT and PAH.

The Role of Endogenous Carbon Monoxide in the Hypoxic Vascular Remodeling of Rat Model of Hypoxic Pulmonary Hypertension

We investigated the expression of heme oxygenase 1 (HO 1) gene and production of endogenous carbon monoxide (CO) in the rat lung tissue at different time points of chronic hypoxic pulmonary hypertension and the effect of hemin on the expression of HO 1 gene and pulmonary hypertension. A rat model of hypoxic pulmonary hypertension was recreated by exposure to intermittent normobaric hypoxic environment (10 % O 2). Reverse transcriptase polymerase chain reaction (RT PCR) was performed to determine the level of HO 1 mRNA in the rat lung tissue and double wave length spectrophotometry was used to evaluate the quantity of COHb in arterial blood. Cardiac catheterization was employed to measure the right ventricular systolic pressure (RVSP) and HE staining was performed in dissected lung tissue to observe the pathological changes of the intra acinar pulmonary arteries (IAPA). It was found that (1) There was a low level of HO 1 mRNA in normal rat lung tissue, but the level of HO 1 mRNA increased by 2-4 times in the lung tissue of hypoxic rats ( P <0.01). The quantity of COHb was 2-3 times those of control group ( P <0.01 or P <0.05). These were accompanied by the increased of RVSP and the thickened IAPA; (2) Hemin could keep the HO 1 mRNA and COHb in the hypoxic rat lung tissue at a high level, and partially suppressed the increase of rat RVSP, thereby ameliorating the pathological changes of IAPA. In conclusion, the upregulation of the expression of HO 1 gene and production of CO in the rat lung of hypoxic pulmonary hypertension plays a role of inhibition in the development of hypoxic pulmonary hypertension. Hemin has a therapeutic effect on hypoxic pulmonary hypertension.

Effect of stellate block on vasomotor factor, vascular endothelial nitricoxide synthase and pulmonary arterial pressure in rabbits with hypoxic pulmonary artery hypertension

BACKGROUND： At present, inhalation of nitrogen monoxidum （NO） or other angiotenic is widely used to cure hypoxic pulmonary artery hypertension. In addition, recent researches demonstrate that postganglionic fiber of stellate ganglion can regulate contents of blood vessel endothelium-calcitonin gene-related peptide （BVE-CGRP） and nitricoxide synthase （NOS） in lung tissue. Therefore, stellate ganglion which is blocked with the local anesthetic may cause therapeutic effects on hypoxic pulmonary artery hypertension. OBJECTIVE： To observe the effects of stellate block on calcitonin gene-related peptide （CGRP） of vasodilation factors, prostacyclin, endothelin-i of vasoconstriction factors, thromboxan, blood vessel endothelium-nitricoxide synthase （BVE-NOS） and mean arterial pressure of lung tissue in rabbits with hypoxic pulmonary artery hypertension. DESIGN： Randomly controlled animal study. SETTING： Neurological Institute of Taihe Hospital Affiliated to Yunyang Medical College. MATERIALS： A total of 24 adult Japanese rabbits of both genders and weighing 2.3 - 2.6 kg were provided by Animal Experimental Center of Hubei Academy of Medical Science. SP kit was provided by Beijing Zhongshan Biotechnology Co., Ltd.; moreover, kits of endothelin-1, CGRP, prostacyclin and thromboxan were provided by Radioimmunity Institute, Scientific and Technological Developing Center, General Hospital of Chinese PLA, and color image analytical system （Leica-Q500IW） was made in Germany. METHODS：The experiment was carried out in the Neurological Institute of Taihe Hospital affiliated to Yunyang Medical College from February to December 2002. ① Rabbits were performed with aseptic manipulation to exposure left stellate ganglion and then it was put in epidural catheter for 1 week. In addition, one end of epidural catheter was fixed near by stellate ganglion and the other end was fixed through dorsal neck. All rabbits were randomly divided into 4 groups, including normal control group, stellate block group, hypoxia group and hypoxia ＋ stellate block group, with 6 in each group. Rabbits in the normal control group were perfused with saline through epidural catheter with 0.5 mL once for three times per day and 3 successive days in total; in addition, rabbits in the stellate block group were perfused with 2.5 g/L bupivacaine through epidural catheter with 0.5 mL once for three times per day and 3 successive days in total. Rabbits in the hypoxia group were used to establish hypoxic pulmonary artery hypertension models. That was to say, the experimental rabbits were put in hypoxic box （containing sodalime and calcium chloride to absorb CO2 and water） and given various flows of oxygen and nitrogen through the two lateral wells simultaneously. And then, oxygen was monitored with oxygen-concentration monitoring device to control the concentration in （10±2）% for 8 hours per day and 2 successive weeks in total. Rabbits in the hypoxia ＋ stellate block group were used to establish hypoxia models as the same as those in the hypoxia group. Two weeks later, 2.5 g,/L bupivacaine was pushed into epidural catheter with 0.5 mL once for three times per day and 3 successive days in total. Breast was directly opened to measure mean pulmonary artery pressure.② 6 mL blood was collected through pulmonary arterial duct to measure levels of plasma CGRP, prostacyclin, endothelin-I and thromboxane with radio-immunity technique; meanwhile, immunohistochemical staining was used to observe the changes of BVE-NOS content of the experimental rabbits in all groups. MAIN OUTCOME MEASURES： Changes of CGRP, prostacyclin, endothelin-1 and thromboxane and BVE-NOS. RESULTS： A total of 24 experimental rabbits were involved in the final analysis. ①As compared with those in the normal control group, hypoxic pulmonary artery hypertension of the experimental rabbits was higher in the hypoxia group and hypoxia ＋ stellate block group after hypoxia [（3.8±0.30）, （3.16±0.45）, （2.60± 0.27） kPa, P 〈 0.05, 0.01]; CGRP was lower [（68.20 ±8.78）, （108.24 ±14.35）, （130.25 ±22.70） ng/L, P 〈 0.05, 0.01]; prostacyclin was lower [（94.45± 10.68）, （98.77± 12.31）, （155.27±20.67） ng/L, P 〈 0.01]; endothelin-1 was higher [（184.7±29.66）, （115.27± 13.62）, （98.20±11.52）, ng/L, P 〈 0.05, 0.01]; thromboxan was higher [（226.27 ±30.46）, （207.67 ±27.32）, （124.25 ± 16.89） ng/L, P 〈 0.01 ]. As compared with that in hypoxia group, hypoxic pulmonary artery hypertension was decreased in hypoxia ＋ stellate block group （P 〈 0.05）, CGRP was increased （P 〈 0.01）, and endothelin-1 was decreased remarkably （P 〈 0.05）. ② Level of BVE-NOS of the experimental rabbits was higher in stellate block group, hypoxia group and hypoxia ＋ stellate block group than that in the normal control group [（0.25±0.06）, （0.27±0.07）, （0.46± 0.12）, （0.14±0.03）, P 〈 0.05], and NOS level was higher in the hypoxia ＋ stellate block group than that in hypoxia group （P 〈 0.05）. CONCLUSION： Mean arterial pressure is decreased in rabbits with hypoxic pulmonary artery hypertension after stellate block and level of endothelin-1 is also decreased; however, levels of CGRP and NOS are increased respectively.

Inhibition of Expression of Hypoxia-inducible Factor-1α mRNA by Nitric Oxide in Hypoxic Pulmonary Hypertension Rats

In order to study the effect of nitric oxide (NO) on the expression of hypoxia inducible factor 1 alpha (HIF 1α) mRNA in hypoxic pulmonary hypertension (HPH) rats, 30 healthy male Wistar rats were randomly divided into normoxic control group, chronic hypoxic group and hypoxia plus L argine (L Arg) group. The animal model of HPH was developed. The mean pulmonary arterial pressure (mPAP) was measured by inserting a microcatheter into the pulmonary artery. The HIF 1α mRNA expression levels were detected by in situ hybridization (ISH) and semiquantitative RT PCR. It was found that after 14 days hypoxia, the mPAP in normoxic control group (17.6±2 7 mmHg,1 mmHg=0 133 kPa) was significantly lower than that in chronic hypoxic group(35.8±6.1 mmHg, t =0.2918, P <0.05) and mPAP in chronic hypoxic group was higher than that in hypoxia plus L argine group(24.4±3.8 mmHg, t =0.2563, P <0.05). ISH showed that the expression of HIF 1α mRNA in the intraacinar pulmonary arteriolae (IAPA) in normoxic control group (0.1076±0.0205) was markedly weaker than that in chronic hypoxic group (0.3317±0.0683, t =3.125, P <0.05) and that in chronic hypoxic group was stronger than that in hypoxia plus L argine group (0.1928±0.0381, t =2.844, P <0.05). RT PCR showed that the content of HIF 1α mRNA in chronic hypoxic group (2.5395±0.6449) was 2.16 times and 1.75 times higher than that in normoxic control group (1.1781±0.3628) and hypoxia plus L argine group (1.4511±0.3981), respectively. It is concluded that NO can reduce the mPAP by the inhibition of the expression of HIF 1α mRNA, which may be one of the mechanisms through which NO affects the pathogenesis of HPH.

Risk Stratification and Prognosis of Pulmonary Arterial Hypertension Associated with Congenital Heart Disease

Background:Current guidelines for managing pulmonary arterial hypertension(PAH)recommend a risk strati-fication approach.However,the applicability and accuracy of these strategies for PAH associated with congenital heart disease(PAH-CHD)require further validation.This study aims to validate the reliability and predictive accuracy of a simplified stratification strategy for PAH-CHD patients over a three-year follow-up.Additionally,new prognostic variables are identified and novel risk stratification methods are developed for assessing and managing PAH-CHD patients.Methods:This retrospective study included 126 PAH-CHD patients.Clinical and biochemical variables across risk groups were assessed using Kruskal-Wallis and Fisher’s exact tests.Indepen-dent risk factors were identified using ordered logistic regression,while Kaplan-Meier and Cox proportional hazards regression analyses evaluated their impact on all-cause mortality.A new stratification model for the PAH-CHD population was constructed based on these analyses.Results:Significant survival differences across stratified risk groups were observed(p<0.001),validating the effectiveness of the simplified risk stratification method in PAH-CHD patients.Prothrombin activity was a strong independent predictor of adverse outcomes of PAH-CHD patients(Hazard ratio 0.95,p<0.001,C-index 0.70).A model combining N-terminal pro-brain natriuretic peptide,prothrombin activity,albumin,and right atrial area achieved an area under the curve of 0.89 and a C-index of 0.85.Conclusions:The simplified risk stratification method is applicable to PAH-CHD patients.Prothrombin activity is a strong independent predictor of adverse outcomes.A comprehensive risk stratification approach,incorporating both established and novel biomarkers,enhances accessibility and offers predictive efficacy during follow-up for PAH-CHD patients,comparable to established models.

Treatment and Clinical Management of Chronic Thromboembolic Pulmonary Hypertension:An Update of Literature Review

Chronic thromboembolic pulmonary hypertension(CTEPH)is a chronic,progressive,debilitating,and life-threa-tening complication of pulmonary embolism(PE).Recent technological advances have permitted various treat-ment options for the treatment of CTEPH,including surgery,angioplasty,and medical treatment,depending on the location and characteristics of lesions.Pulmonary endarterectomy(PEA)is the treatment of choice for CTEPH,as it offers excellent long-term outcomes and a high probability of recovery.Moreover,various medical and interventional therapies are currently being developed for patients with inoperable CTEPH.This review mainly summarizes the current treatment approaches of CTEPH,offering more options for specialist physicians to,thus,better manage chronic thromboembolic syndromes.

Development of pulmonary hypertension remains a major hurdle to corrective surgery in Down syndrome

Down syndrome is the most common chromosomal abnormality encountered in clinical practice with 50%of them having associated congenital heart disease(CHD).Shunt lesions account for around 75%of all CHDs in Down syndrome.Down syndrome patients,especially with large shunts are particularly predisposed to early development of severe pulmonary hypertension(PH)compared with shunt lesions in general population.This necessitates timely surgical correction which remains the only viable option to prevent long term morbidity and mortality.However,despite clear recommendations,there is wide gap between actual practice and fear of underlying PH which often leads to surgical refusals in Down syndrome even when the shunt is reversible.Another peculiarity is that Down syndrome patients can develop PH even after successful correction of shunt.It is not uncommon to come across Down syndrome patients with uncorrected shunts in adulthood with irreversible PH at which stage intracardiac repair is contraindicated and the only option available is a combined heartlung transplant.However,despite the guidelines laid by authorities,the rates of cardiac transplant in adult Down syndrome remain dismal largely attributable to the high prevalence of intellectual disability in them.The index case presents a real-world scenario highlighting the impact of severe PH on treatment strategies and discrimination driven by the fear of worse outcomes in these patients.

The Potential of Circular RNAs as Biomarkers in Pulmonary Arterial Hypertension Related to Congenital Heart Disease

A particular type of endogenous noncoding RNAs known as circular RNAs(circRNAs)has now become possible biomarkers for several diseases because of their stability and tissue-specific expression patterns.CircRNAs might play a role in various of biological processes.The identification of particular circRNAs dysregulated in pulmonary arterial hypertension(PAH)raises the possibility of these molecules serving as biomarkers for the disease’s early diagnosis and treatment.This review mainly summarizes the role and potential of circRNA as a future biomarker in PAH related to congenital heart disease.This study presented several potential circRNA targets as diagnostic biomarkers for PAH,discussed their biological functions,and addressed the challenges that need to be considered for their application in clinical settings.

Mufangji tang ameliorates pulmonary arterial hypertension through improving vascular remodeling,inhibiting inflammatory response and oxidative stress,and inducing apoptosis

Background:Mufangji tang(MFJT)is composed of Ramulus Cinnamomi,Radix Ginseng,Cocculus orbiculatus(Linn.)DC.,and Gypsum.In clinical settings,MFJT has been effectively employed in addressing a range of respiratory disorders,notably including pulmonary arterial hypertension(PAH).However,the mechanism of action of MFJT on PAH remains unknown.Methods:In this study,a monocrotaline-induced PAH rat model was established and treated with MFJT.The therapeutic effects of MFJT on PAH rat model were evaluated.Network pharmacology was conducted to screen the possible targets for MFJT on PAH,and the molecular docking between the main active components and the core targets was carried out.The key targets identified from network pharmacology were tested.Results:Results showed significant therapeutic effects of MFJT on PAH rat model.Analysis of network pharmacology revealed several potential targets related to apoptosis,inflammation,oxidative stress,and vascular remodeling.Molecular docking showed that the key components were well docked with the core targets.Further experimental validation results that MFJT treatment induced apoptosis(downregulated Bcl-2 levels and upregulated Bax levels in lung tissue),inhibited inflammatory response and oxdative stress(decreased the levels of IL-1β,TNF-α,inducible NOS,and malondialdehyde,and increased the levels of endothelial nitric oxide synthase,nitric oxide,glutathione and superoxide dismutase),reduced the proliferation of pulmonary arterial smooth muscle cells(downregulated ET-1 andβ-catenin levels and ERK1/2 phosphorylation,increased GSK3βlevels).Conclusion:Our study revealed MFJT treatment could alleviate PAH in rats via induction of apoptosis,inhibition of inflammation and oxidative stress,and the prevention of vascular remodeling.

Intervention control of aerobic exercise in maintaining quality of life and pulmonary hypertension in hemodialysis patients

BACKGROUND Pulmonary hypertension is a serious complication in the treatment of maintenance hemodialysis patients,which seriously affects the quality of life of patients and threatens their life safety.Prevention,treatment and improvement of pulmonary hypertension are of great significance to improve the quality of life of patients.AIM To investigate the intervention and control of pedal-powered bicycle in maintaining quality of life and pulmonary hypertension in hemodialysis patients.METHODS 73 patients with maintenance hemadialysis combined with pulmonary arterial hypertension at a hemodialysis center in a certain hospital from May 2021 to May 2022 are selected.Patients are divided into two groups,37 cases in the control group(group C)and 36 cases in the intervention group(group I).Patients are divided into two groups,group C is treated with oral administration of betaglandin sodium combined with routine nursing care.Based on group C,group I conducts power cycling exercises.RESULTS After treatment,group I patients had higher muscle strength,36-Item Short Form Health Survey scores,and Kidney Disease Targets Areas scores;The 6-minute walk distance test index level was higher and the Borg score was lower;The group I had lower systolic blood pressure,greater vital capacity,higher positive emotion,lower systolic pulmonary artery pressure index level,higher arterial partial oxygen pressure level,lower pulmonary vascular resistance index level,and higher blood oxygen saturation level[158.91±11.89 vs 152.56±12.81,1795.01±603.18 vs 1907.20±574.15,24.00(22.00,29.00)vs 24.00(22.00,28.00),P<0.001].CONCLUSION Aerobic exercise combined with Western medicine treatment can effectively improve patients'pulmonary hypertension,alleviate their negative emotions,and enable them to achieve a higher level of quality of life.

Hypoxic pulmonary hypertension and novel ATP-sensitive potassium channel opener: the new hope on the horizon

Hypoxic pulmonary hypertension(HPH) is a syndrome characterized by the increase of pulmonary vascular tone and the structural remodeling of peripheral pulmonary arteries.The aim of specific therapies for hypoxic pulmonary hypertension is to reduce pulmonary vascular resistance,reverse pulmonary vascular remodeling,and thereby improving right ventricular function.Iptakalim,a lipophilic para-amino compound with a low molecular weight,has been demonstrated to be a new selective ATP-sensitive potassium(K ATP) channel opener via pharmacological,electrophysiological,biochemical studies,and receptor binding tests.In hypoxia-induced animal models,iptakalim decreases the elevated mean pressure in pulmonary arteries,and attenuates remodeling in the right ventricle,pulmonary arteries and airways.Furthermore,iptakalim has selective antihypertensive effects,selective vasorelaxation effects on smaller arteries,and protective effects on endothelial cells,but no effects on the central nervous,respiratory,digestive or endocrine systems at therapeutic dose.Our previous studies demonstrated that iptakalim inhibited the effects of endothelin-1,reduced the intracellular calcium concentration and inhibited the proliferation of pulmonary artery smooth muscle cells.Since iptakalim has been shown safe and effective in both experimental animal models and phase I clinical trials,it can be a potential candidate of HPH in the future.

Independent prognostic value of lipocalin-2 in congenital heart disease-associated pulmonary artery hypertension

BACKGROUND Timely and accurate evaluation of the patient's pulmonary arterial pressure(PAP)is of great significance for the treatment of congenital heart disease.Currently,there is no non-invasive gold standard method for evaluating PAP.AIM To assess the prognostic value of lipocalin-2(LCN2)in relation to PAP in patients with congenital heart disease associated with pulmonary artery hypertension.METHODS We conducted a retrospective analysis of 69 pediatric patients diagnosed with ventricular septal defects.The patients’clinical and laboratory data were collected.The serum LCN2 concentrations were compared between the pulmonary arterial hypertension(PAH)group and the nonPAH group.The correlation of LCN2 concentration with PAH classification was evaluated using binary logistic regression analysis.The receiver operating characteristic(ROC)curve was used to evaluate the diagnostic potential of LCN2 for PAH.RESULTS Serum LCN2 concentration significantly correlated with patients’mean PAP(r=0.544,P<0.001),but not correlated with creatinine(P=0.446)or blood urea nitrogen(P=0.747).LCN2 levels were significantly correlated with PAH in both univariate[odds ratio(OR)1.107,95%CI:1.033-1.185,P=0.004)]and multivariate regression analysis(OR 1.150,95%CI:1.027-1.288,P=0.015).ROC curve analysis revealed an area under the curve of 0.783 for LCN2.At the cutoff value of 19.42 ng/mL,the sensitivity and specificity of LCN2 for diagnosing PAH is 90.19%and 55.56%,respectively.LCN2 concentration also significantly correlated with the post-repair mean PAP in patients with congenital heart disease(r=0.532,P=0.009).CONCLUSION LCN2 is emerging as a candidate biomarker for assessing PAP in patients with congenital heart disease.Its high sensitivity in diagnosing PAH makes it a valuable tool in patient management.

Pulmonary hypertension post-liver transplant:A case report

BACKGROUND Liver transplantation(LTx)is vital in patients with end-stage liver disease,with metabolic dysfunction-associated steatotic liver disease being the most common indication.Primary sclerosing cholangitis(PSC)is an important indication.Portopulmonary hypertension,associated with portal hypertension,poses a significant perioperative risk,making pretransplant screening essential.CASE SUMMARY We report the case of a 41-year-old woman with PSC who developed severe pul-monary hypertension years after a successful LTx.She presented with worsening dyspnea on exertion and presyncope.Diagnostic evaluation confirmed severe precapillary pulmonary hypertension without evidence of recurrent portal hy-pertension.Initial management with Sildenafil and Macitentan led to a significant improvement in her symptoms,exercise capacity,and biomarkers.This case highlights the rare development of de novo pulmonary hypertension in a liver transplant recipient without recurrent portal hypertension,possibly linked to autoimmune processes or primary liver disease itself.The patient’s positive re-sponse to the combination therapy underscores the importance of prompt diag-nosis and aggressive management.CONCLUSION In conclusion,pulmonary arterial hypertension post-LTx is a rare but serious complication with a poor prognosis,necessitating further research to better understand its mechanisms and to develop effective strategies for prevention and treatment.

Impact of diabetes mellitus on mortality in pulmonary hypertension:A systematic review and meta-analysis

BACKGROUND Pulmonary hypertension(PH)is a progressive disease characterized by endothelial dysfunction and vascular remodeling and is a leading cause of mortality worldwide.Although it is independently associated with multiple comorbidities,the impact of diabetes mellitus(DM)on mortality in patients with PH remains uncertain.To address this issue,we conducted a systematic review and meta-analysis to investigate the effect of DM on survival in patients with pulmonary hypertension.AIM To investigate the impact of diabetes mellitus on mortality in pulmonary hypertension patients.METHODS We conducted a comprehensive search of four major electronic bibliographic databases like PubMed,Google Scholar,Scopus,and Embase,and identified 106 relevant studies,out of 1561 articles,published since the year 2000 for full-text review.Fourteen retrospective and prospective cohort studies that compared survival between patients with DM and those without DM in the context of PH were deemed eligible for inclusion in our meta-analysis.The study was registered on PROSPERO with the identifier CRD42023390232.RESULTS A total of 116455 patients with PH were included in the meta-analysis,of whom 41228 suffered from DM and 75227 did not.The results of our meta-analysis indicate an elevated mortality rate among PH patients with diabetes mellitus in comparison to those without DM[odds ratio(OR)=1.40,95%CI:1.15–1.70,P=0.0006].The metaregression analysis unveiled a statistically significant negative association between mean age and effect size(coefficient=-0.036,P value=0.018).Conversely,a statistically significant positive association was detected between female proportion and effect size(coefficient=0.000,P value<0.001).CONCLUSION Our meta-analysis,which included approximately 116500 PH patients,revealed that the presence of diabetes mellitus was associated with increased odds of mortality when compared to non-diabetic patients.The metaregression analysis indicates that studies with older participants and lower proportions of females tend to exhibit smaller effect sizes.Clinically,these findings underscore the importance of incorporating diabetes status into the risk stratification of patients with PH with more aggressive monitoring and early intervention to improve prognosis potentially.

Effects of combined aerobic,resistance and inspiratory training in patients with pulmonary hypertension:A systematic review

BACKGROUND Pulmonary hypertension(PH)is a serious progressive disorder of the modern world,characterized by endothelial dysfunction and impaired vasoreactivity.Patients with PH usually present exercise intolerance from the very early stages and reduced exercise capacity.Exercise training has been shown to have beneficial effects in patients with cardiovascular comorbidities.However,data regarding the effects of combined exercise training programs in patients with PH still remains limited.AIM To investigate the effects of combined exercise training programs on exercise capacity and quality of life in patients with PH.METHODS Our search included all available randomized controlled trials(RCTs)regarding combined aerobic,resistance and inspiratory training programs in patients with PH in 4 databases(Pubmed,PEDro,Embase,CINAHL)from 2012 to 2022.Five RCTs were included in the final analysis.Functional capacity,assessed by peak VO_(2)or 6-min walking test(6MWT),as well as quality of life,assessed by the SF-36 questionnaire,were set as the primary outcomes in our study.RESULTS Peak VO_(2)was measured in 4 out of the 5 RCTs while 6MWT was measured in all RCTs.Both indices of functional capacity were significantly increased in patients with PH who underwent combined exercise training compared to the controls in all of the included RCTs(P<0.05).Quality of life was measured in 4 out of 5 RCTs.Although patients improved their quality of life in each group,however,only 2 RCTs demonstrated further improvement in patients performing combined training compared to controls.CONCLUSION By this systematic review,we have demonstrated that combined aerobic,resistance and inspiratory exercise training is safe and has beneficial effects on aerobic capacity and quality of life in patients with PH.Such exercise training regimen may be part of the therapeutic strategy of the syndrome.

Methylene blue could transiently reverse the vasodilator effect of inhaled nitric oxide in canine hypoxic pulmonary hypertension mode

Low dose inhalation of nitric oxide could selectively lower pulmonary hypertension. But increasing methemoglobin (MeHb) formation is one of its side effects. This study aimed to investigate whethermethylene blue (MB) could attenuate the therapeutic effect of nitric oxide (NO) while reducing methemoglobin.Methods: The effect of administering MB 2 mg.kg-1 intravenously on mean pulmonary arterial pressure (MPAP)was observed after the inhalation of 90±7 vpm (volume per million) NO in nine dogs with pulmonary hypertension induced by hypoxia (FiO2=0.08). Results: Inha1ation of NO significantly decreased MPAP (P<0.01) from 2. 6±0.9kPa to 2.0±0.6 kPa. After intravenous administration of MB, the pulmonary vasodilator effect of inhaled NO (P<0.01) was partly reversed, MPAP increased from 2. 01±0. 6 kPa to 2. 3±0. 7 kPa, and cardiac output (CO) significantly increased (P<0. 05). But the effects lasted on1y 5 min. Couclusion: MB could transiently and partly reverse the pulmonary vasodilator action of inhaled NO in canine hypoxic pulmonary hypertension mode.The MB should be carefully used in severe pulmonary hypertension.

Role of Na^+/H^+ antiporter in pulmonary artery smooth muscle of hypoxic pulmonary hypertension in the rat

Objective: To investigate the role of Na+ /H+ antiporter in the hypoxic pumonary hypertension ofrats. Methods: Thirty Wistar rats were randomly divided into 3 groups with 10 in each group: controlgroup, 3--week hypoxia group and 8--week hypoxia group. After the isolation of pulmonary artery smoothmuscles, pHi was determined by fluorescence measurement of the pH--sensitive dye BCECF and theexpression of NHE--1 mRNA was detected with reverse transcription--polymerase chain reaction. Results: ThepHi and expression of NHE-1 mRNA of pulmonary artery smooth muscle cell in the hypoxia groups weresignificantly increased than those in the normal group (P < 0. 01 ). There was no remarkable differencebetween the hypoxia groups. Conclusion: With the function of regulation pHi., NHE--1 may play an importantrole in the pulmonary vascular remodeling of pulmonary hypertension. The result provides a new therapeuticmethod with NHE--1 inhibitors and/or gene therapy for the hypoxic pulmonary hypertension.

Effect of Ligusticum Chuanxiong on Hypoxic Pulmonary Hypertension in Rats and Its Mechanism

Objective: To explore the mechanism of Chuanxiong in alleviating hypoxic pulmonary hypertension in rats by inhibiting pulmonary vascular remodeling. Methods: Thirty healthy and clean male SD rats weighing (180 - 220) g were randomly divided into three groups (n = 10): normoxia group (n), hypoxia group (H) and Chuanxiong group (L). Group N was fed in normoxic environment, and the other two groups were fed in hypoxic (9% 11% O2) environment for 4 weeks, 8 h/D, 6 days a week. Rats in group L were gavaged with Ligusticum chuanxiong solution diluted with normal saline at the concentration of 300 mg/kg, and rats in group H were gavaged with equal volume of normal saline. After 4 weeks, the mean pulmonary artery pressure was measured. After pulmonary perfusion, the right ventricular free wall and left ventricle plus ventricular septum were taken to measure the right ventricular hypertrophy index. The changes of pulmonary morphology and ultrastructure were observed under light microscope. Results: Compared with group n, the average pulmonary artery pressure and right ventricular hypertrophy index in the other two groups increased, and the thickening of pulmonary vascular wall was obvious under microscope (P Conclusion: Ligusticum chuanxiong can relieve pulmonary artery pressure in rats by inhibiting pulmonary vascular remodeling.

Effect of safflower injection on endoplasmic reticulum stress-induced apoptosis in rats with hypoxic pulmonary hypertension

Objective To explore the effects of safflower injection on prevention and treatment of hypoxic pulmonary hypertension and clarify the function of the endoplasmic reticulum stress apoptosis pathway during the process.Methods Thirty male SD rats were randomly grouped as normal control group,hypoxiahypercapnia group and hypoxia+safflower group.The latter two groups were put in the cabin with oxygen concentration ranged from 9% to 11% and carbon dioxide concentration from 5% to 6%.The pulmonary artery pressure and the index of right ventricular hypertrophy were determined after hypoxia exposure(8 h/d×28 d).Changes in morphology of lung tissue were observed by electron microscopy.To explore the possible mechanisms,we also detected apoptosis and apoptosis-related genes/proteins in lung tissue by TUNEL reactivity and PCR and Western blot.Results Compared with the normal control group,pulmonary artery pressure and the index of right ventricular hypertrophy in hypoxia group were 45% and 33.4% higher,respectively.Tiny blood vessel wall of lungs was thickened and edema,and proliferation of collagen fibers was obvious under the electron microscope.TUNEL staining of apoptotic cells in lung tissues showed more high brightness green fluorescence(+～++),but less green fluorescence showed in the pulmonary vascular smooth muscle cell layer,and apoptosis index(AI) value was 150% higher;gene and protein expression levels of endoplasmic reticulum stress pathway were increased.Compared with hypoxia-hypercapnia group,pulmonary artery pressure and the index of right ventricular hypertrophy in the hypoxia+safflower group were 18% and 15.6% lower,respectively;collagen fibers were decreased,and smooth muscle cells and epithelial cells were got apoptotic-like changes under the electron microscope.TUNEL staining of apoptotic cells in lung tissues showed brighter green fluorescence(++～+++);the high brightness green fluorescence showed in pulmonary vascular smooth muscle cell layer,and apoptotic index(AI) value was 40% higher;gene and protein expressions of endoplasmic reticulum stress pathway were significantly upregulated.Conclusion Our findings demonstrate that safflower injection could activate endoplasmic reticulum stressinduced apoptosis and especially promote apoptosis in pulmonary vascular smooth muscle cells.