Echocardiographic features of right ventricle in septic patients with elevated central venous pressure.

BACKGROUND: Elevated central venous pressure (CVP) is deemed as a sign of right ventricular (RV) dysfunction. We aimed to characterize the echocardiographic features of RV in septic patients with elevated CVP, and quantify associations between RV function parameters and 30-day mortality. METHODS: We retrospectively reviewed a cohort of septic patients with CVP ≥ 8 mmHg in a tertiary hospital intensive care unit. General characteristics and echocardiographic parameters including tricuspid annular plane systolic excursion (TAPSE), pulmonary vascular resistance (PVR) as well as prognostic data were collected. Associations between RV function parameters and 30-day mortality were assessed using Cox regression models. RESULTS: Echocardiography was performed in 244 septic patients with CVP ≥ 8 mmHg. Echocardiographic findings revealed that various types of abnormal RV function can occur individually or collectively. Prevalence of RV systolic dysfunction was 46%, prevalence of RV enlargement was 34%, and prevalence of PVR increase was 14%. In addition, we collected haemodynamic consequences and found that prevalence of systemic venous congestion was 16%, prevalence of RV-pulmonary artery decoupling was 34%, and prevalence of low cardiac index (CI) was 23%. The 30-day mortality of the enrolled population was 24.2%. In a Cox regression analysis, TAPSE (HR:0.542, 95% CI:0.302-0.972, p = 0.040) and PVR (HR:1.384, 95% CI:1.007-1.903, p = 0.045) were independently associated with 30-day mortality. CONCLUSIONS: Echocardiographic findings demonstrated a high prevalence of RV-related abnormalities (RV enlargement, RV systolic dysfunction and PVR increase) in septic patients with elevated CVP. Among those echocardiographic parameters, TAPSE and PVR were independently associated with 30-day mortality in these patients.

Bariatric surgery mitigated electrocardiographic abnormalities in patients with morbid obesity.

Obesity can lead to cardiovascular dysfunctions and cause electrocardiographic disruptions. Bariatric surgery plays a significant role in weight loss. To assess its benefits, this study investigated electrocardiographic changes before and after bariatric surgery. The present article describes a retrospective cohort study with a 6-month follow-up period. Electrocardiograms were interpreted and compared before and six months after surgery. The relationships between weight loss, type of surgery, and electrocardiographic alterations were analyzed. A total of 200 patients participated in the study, with 34 (17%) men and 166 (83%) women. The mean age of the participants was 44.6 ± 8.6, and their mean body mass index was 43.8 ± 5.5 kg/m2. The mean of QTc decreased after the surgery, while the Sokolow-Lyon scores increased. The statistical analysis showed that QTc dispersion (> 40) (P < 0.001), right ventricular hypertrophy (P < 0.001), abnormal R wave progression (P < 0.001), QTc (P < 0.001) and Sokolow-Lyon criteria (P < 0.001) significantly changed postoperatively. In conclusion, bariatric surgery can reduce QTc, correct poor R wave progression, and resolve right ventricular hypertrophy (RVH) in patients with morbid obesity.

Forsythoside B Mitigates Monocrotaline-Induced Pulmonary Arterial Hypertension via Blocking the NF-κB Signaling Pathway to Attenuate Vascular Remodeling.

Purpose: Pulmonary arterial hypertension (PAH) is a devastating disease with little effective treatment. The proliferation of pulmonary artery smooth muscle cells (PASMCs) induced by the nuclear factor-κB (NF-κB) signaling activation plays a pivotal role in the pathogenesis of PAH. Forsythoside B (FTS•B) possesses inhibitory effect on NF-κB signaling pathway. The present study aims to explore the effects and mechanisms of FTS•B in PAH. Methods: Sprague-Dawley rats received monocrotaline (MCT) intraperitoneal injection to establish PAH model, and FTS•B was co-treated after MCT injection. Right ventricular hypertrophy and pulmonary artery pressure were measured by echocardiography and right heart catheterization, respectively. Histological alterations were detected by H&E staining and immunohistochemistry. FTS•B's role in PASMC proliferation and migration were evaluated by CCK-8 and wound healing assay. To investigate the underlying mechanisms, Western blotting, immunofluorescence staining and ELISA were conducted. The NF-κB activator PMA was used to investigate the role of NF-κB in FTS•B's protective effects against PAH. Results: FTS•B markedly alleviated MCT-induced vascular remodeling and pulmonary artery pressure, and improved right ventricular hypertrophy and survival. FTS•B also reversed PDGF-BB-induced PASMC proliferation and migration, decreased PCNA and CyclinD1 expression in vitro. The elevated levels of IL-1ß and IL-6 caused by MCT were decreased by FTS•B. Mechanistically, MCT-triggered phosphorylation of p65, IκBα, IKKα and IKKß was blunted by FTS•B. FTS•B also reversed MCT-induced nuclear translocation of p65. However, all these protective effects were blocked by PMA-mediated NF-κB activation. Conclusion: FTS•B effectively attenuates PAH by suppressing the NF-κB signaling pathway to attenuate vascular remodeling. FTS•B might be a promising drug candidate with clinical translational potential for the treatment of PAH.

Effect of free and nanoemulsified ß-caryophyllene on monocrotaline-induced pulmonary arterial hypertension.

Pulmonary arterial hypertension (PAH) is characterized by increased pulmonary vascular resistance (PVR), right ventricular (RV) failure and premature death. Compounds with vasodilatory characteristics, such as ß-caryophyllene, could be promising therapeutics for PAH. This study aimed to determine the effects of free and nanoemulsified ß-caryophyllene in lung oxidative stress and heart function in PAH rats. Male Wistar rats (170 g, n = 6/group) were divided into four groups: control (CO), monocrotaline (MCT), monocrotaline + ß-caryophyllene (MCT-Bcar) and monocrotaline + nanoemulsion with ß-caryophyllene (MCT-Nano). PAH was induced by MCT (60 mg/kg i.p.), and 7 days later, treatment with ß-caryophyllene, either free or in a nanoemulsion (by gavage, 176 mg/kg/day) or vehicle was given for 14 days. Echocardiographic and hemodynamic measurements were performed, and after, the RV was collected for morphometry and the lungs for evaluation of oxidative stress, antioxidant enzymes, total sulfhydryl compounds, nitric oxide synthase (NOS) activity and endothelin-1 receptor expression. RV hypertrophy, increased PVR and RV systolic and diastolic pressures (RVSP and RVEDP, respectively) and increased mean pulmonary arterial pressure (mPAP) were observed in the MCT group. Treatment with both free and nanoemulsified ß-caryophyllene reduced RV hypertrophy, mPAP, RVSP and lipid peroxidation. The reduction in RVSP was more pronounced in the MCT-Nano group. Moreover, RVEDP decreased only in the MCT-Nano group. These treatments also increased superoxide dismutase, catalase and NOS activities and decreased endothelin-1 receptors expression. Both ß-caryophyllene formulations improved mPAP, PVR and oxidative stress parameters. However, ß-caryophyllene in a nanoemulsion was more effective in attenuating the effects of PAH.

Cannabidiol may prevent the development of congestive hepatopathy secondary to right ventricular hypertrophy associated with pulmonary hypertension in rats.

BACKGROUND: Pulmonary hypertension (PH) can cause right ventricular (RV) failure and subsequent cardiohepatic syndrome referred to as congestive hepatopathy (CH). Passive blood stasis in the liver can affect inflammation, fibrosis, and ultimately cirrhosis. Cannabidiol (CBD) has many beneficial properties including anti-inflammatory and reduces RV systolic pressure and RV hypertrophy in monocrotaline (MCT)-induced PH in rats. Thus, it suggests that CBD may have the potential to limit CH development secondary to RV failure. The present study aimed to determine whether chronic administration of CBD can inhibit the CH secondary to RV hypertrophy associated with MCT-induced PH. METHODS: The experiments involved rats with and without MCT-induced PH. CBD (10 mg/kg) or its vehicle was administered once daily for 3 weeks after MCT injection (60 mg/kg). RESULTS: Monocrotaline administration increased the liver/body weight ratio. In histology examinations, we observed necrosis and vacuolar degeneration of hepatocytes as well as sinusoidal congestion. In biochemical studies, we observed increased levels of nuclear factor-κappa B (NF-κB), tumour necrosis factor-alpha (TNA-α), interleukin 1 beta (IL-1ß), and interleukin 6 (IL-6). CBD administration to PH rats reduced the liver/body weight ratio, improved the architecture of the liver, and inhibited the formation of necrosis. Cannabidiol also decreased the level of NF-κB, TNF-α, IL-1ß and IL-6. CONCLUSIONS: The studies show that CBD can protect the liver from CH probably through attenuating PH, protective effects on the RV, and possibly direct anti-inflammatory effects on liver tissue through regulation of the NF-κB pathway.

[Effects of human umbilical cord mesenchymal stem cells (MSCs)-derived exosomes on pulmonary vascular remodeling in hypoxic pulmonary hypertension].

The present study aimed to investigate the effect of human umbilical cord mesenchymal stem cells (MSCs)-derived exosomes (MSCs-Exo) on mice with hypoxic pulmonary hypertension (HPH). MSCs were isolated and cultured from human umbilical cords under aseptic conditions, and exosomes were extracted from the supernatants and identified. Healthy SPF C57BL/6 mice were randomly divided into three groups: normoxic group, hypoxic group, and hypoxic+MSCs-Exo group. Mice in the hypoxic group and the hypoxic+MSCs-Exo group were maintained for 28 d at an equivalent altitude of 5 000 m in a hypobaric chamber to establish HPH mouse model. The mice in the hypoxic+MSCs-Exo group were injected with MSCs-Exo via tail vein before hypoxia and on days 1, 3, 5 and 9 of hypoxia, and the mice in the other two groups were injected with PBS. At the end of the experiment, echocardiography was performed to detect pulmonary arterial acceleration time/pulmonary arterial ejection time ratio (PAAT/PET), right ventricular free wall thickness, and right ventricular hypertrophy index RV/(LV+S). HE staining was performed to observe the lung tissue morphology. EVG staining was performed to observe elastic fiber hyperplasia. Immunohistochemistry was performed to detect α smooth muscle actin (α-SMA) expression in lung tissue. Immunofluorescence staining was used to detect macrophage infiltration in lung tissue. qPCR was performed to detect IL-1ß and IL-33 in lung tissue, and cytometric bead array was performed to detect IL-10 secretion. Western blotting was used to detect the M1 macrophage marker iNOS, M2 macrophage marker Arg-1 and IL-33/ST2 pathway proteins in lung tissues. The results showed that hypoxia increased pulmonary artery pressure and pulmonary vascular remodeling, increased macrophage infiltration, IL-1ß and IL-33 expression (P < 0.05) and upregulated the IL-33/ST2 pathway (P < 0.05). Compared with the hypoxic group, MSCs-Exo treatment increased PAAT/PET (P < 0.05), decreased right ventricular free wall thickness (P < 0.05), right ventricular hypertrophy index RV/(LV+S) (P < 0.05), α-SMA expression in small pulmonary vessels (P < 0.05), and inflammatory factors including IL-1ß and IL-33 expression in lung tissue, however increased IL-10 secretion (P < 0.05). In addition, MSCs-Exo treatment upregulated Arg-1 and downregulated iNOS and IL-33/ST2 (P < 0.05). The results suggest that MSC-Exo may alleviate HPH through their immunomodulatory effects.

MicroRNA-34a-Dependent Attenuation of Angiogenesis in Right Ventricular Failure.

BACKGROUND: The right ventricle (RV) is at risk in patients with complex congenital heart disease involving right-sided obstructive lesions. We have shown that capillary rarefaction occurs early in the pressure-loaded RV. Here we test the hypothesis that microRNA (miR)-34a, which is induced in RV hypertrophy and RV failure (RVF), blocks the hypoxia-inducible factor-1α-vascular endothelial growth factor (VEGF) axis, leading to the attenuated angiogenic response and increased susceptibility to RV failure. METHODS AND RESULTS: Mice underwent pulmonary artery banding to induce RV hypertrophy and RVF. Capillary rarefaction occurred immediately. Although hypoxia-inducible factor-1α expression increased (0.12±0.01 versus 0.22±0.03, P=0.05), VEGF expression decreased (0.61±0.03 versus 0.22±0.05, P=0.01). miR-34a expression was most upregulated in fibroblasts (4-fold), but also in cardiomyocytes and endothelial cells (2-fold). Overexpression of miR-34a in endothelial cells increased cell senescence (10±3% versus 22±2%, P<0.05) by suppressing sirtulin 1 expression, and decreased tube formation by 50% via suppression of hypoxia-inducible factor-1α, VEGF A, VEGF B, and VEGF receptor 2. miR-34a was induced by stretch, transforming growth factor-ß1, adrenergic stimulation, and hypoxia in cardiac fibroblasts and cardiomyocytes. In mice with RVF, locked nucleic acid-antimiR-34a improved RV shortening fraction and survival half-time and restored capillarity and VEGF expression. In children with congenital heart disease-related RVF, RV capillarity was decreased and miR-34a increased 5-fold. CONCLUSIONS: In summary, miR-34a from fibroblasts, cardiomyocytes, and endothelial cells mediates capillary rarefaction by suppressing the hypoxia-inducible factor-1α-VEGF axis in RV hypertrophy/RVF, raising the potential for anti-miR-34a therapeutics in patients with at-risk RVs.

Sodium butyrate alleviates right ventricular hypertrophy in pulmonary arterial hypertension by inhibiting H19 and affecting the activation of let-7g-5p/IGF1 receptor/ERK.

Pulmonary arterial hypertension (PAH) is a complex and fatal cardio-pulmonary vascular disease. Decompensated right ventricular hypertrophy (RVH) caused by cardiomyocyte hypertrophy often leads to fatal heart failure, the leading cause of mortality among patients. Sodium butyrate (SB), a compound known to reduce cardiac hypertrophy, was examined for its potential effect and the underlying mechanism of SB on PAH-RVH. The in vivo study showed that SB alleviated RVH and cardiac dysfunction, as well as improved life span and survival rate in MCT-PAH rats. The in vivo and in vitro experiments showed that SB could attenuate cardiomyocyte hypertrophy by reversing the expressions of H19, let-7g-5p, insulin-like growth factor 1 receptor (IGF1 receptor), and pERK. H19 inhibition restored the level of let-7g-5p and prevented the overexpression of IGF1 receptor and pERK in hypertrophic cardiomyocytes. In addition, dual luciferase assay revealed that H19 demonstrated significant binding with let-7g-5p, acting as its endogenous RNA. Briefly, SB attenuated PAH-RVH by inhibiting the H19 overexpression, restoring the level of let-7g-5p, and hindering IGF1 receptor/ERK activation.

Role of Oxygen Starvation in Right Ventricular Decompensation and Failure in Pulmonary Arterial Hypertension.

Right ventricular (RV) function and eventually failure determine outcome in patients with pulmonary arterial hypertension (PAH). Initially, RV responds to an increased load caused by PAH with adaptive hypertrophy; however, eventually RV failure ensues. Unfortunately, it is unclear what causes the transition from compensated RV hypertrophy to decompensated RV failure. Moreover, at present, there are no therapies for RV failure; those for left ventricular (LV) failure are ineffective, and no therapies specifically targeting RV are available. Thus there is a clear need for understanding the biology of RV failure and differences in physiology and pathophysiology between RV and LV that can ultimately lead to development of such therapies. In this paper, we discuss RV adaptation and maladaptation in PAH, with a particular focus of oxygen delivery and hypoxia as the principal drivers of RV hypertrophy and failure, and attempt to pinpoint potential sites for therapy.

Proteomic and Phosphoproteomic Analysis of Right Ventricular Hypertrophy in the Pulmonary Hypertension Rat Model.

Pulmonary arterial hypertension (PAH) is a progressive disease that affects both the lungs and heart. Right ventricle (RV) hypertrophy is a primary pathological feature of PAH; however, its underlying molecular mechanisms remain insufficiently studied. In this study, we employed tandem mass tag (TMT)-based quantitative proteomics for the integrative analysis of the proteome and phosphoproteome of the RV derived from monocrotaline-induced PAH model rats. Compared with control samples, 564 significantly upregulated proteins, 616 downregulated proteins, 622 downregulated phosphopeptides, and 683 upregulated phosphopeptides were identified (P < 0.05, abs (log2 (fold change)) > log2 1.2) in the MCT samples. The quantitative real-time polymerase chain reaction (qRT-PCR) validated the expression levels of top 20 significantly altered proteins, including Nppa (natriuretic peptides A), latent TGF-ß binding protein 2 (Ltbp2), periostin, connective tissue growth factor 2 (Ccn2), Ncam1 (neural cell adhesion molecule), quinone reductase 2 (Nqo2), and tropomodulin 4 (Tmod4). Western blotting confirmed the upregulation of Ncam1 and downregulation of Nqo2 and Tmod4 in both MCT-induced and hypoxia-induced PH rat models. Pathway enrichment analyses indicated that the altered proteins are associated with pathways, such as vesicle-mediated transport, actin cytoskeleton organization, TCA cycle, and respiratory electron transport. These significantly changed phosphoproteins were enriched in pathways such as diabetic cardiomyopathy, hypertrophic cardiomyopathy, glycolysis/gluconeogenesis, and cardiac muscle contraction. In summary, this study provides an initial analysis of the RV proteome and phosphoproteome in the progression of PAH, highlighting several RV dysfunction-associated proteins and pathways.

Right Atrial Enlargement on Electrocardiogram in Previously Healthy Young Patients.

OBJECTIVES: To assess whether right atrial enlargement (RAE) on electrocardiogram (ECG) correlates with true RAE on echocardiogram in previously healthy young patients and to understand which patients with RAE on ECG may warrant additional testing. STUDY DESIGN: A single-center, retrospective review of previously healthy young patients with (1) ECGs that were read as RAE by a pediatric cardiologist and (2) echocardiograms obtained within 90 days of the ECG. ECGs were reviewed to confirm RAE and determine which leads met criteria. The echocardiograms were then reviewed and RA measurements with z scores obtained. A z score >2 was considered positive for RAE on echocardiogram. RESULTS: In total, 162 patients with median age 10.8 years were included in the study. A total of 23 patients had true RAE on echocardiogram, giving a positive predictive value (PPV) of 14%. In patients <1 year of age, the PPV increased to 35%. In patients older than 1 year, the PPV was low at 7%. Patients with true RAE were more likely to meet criteria for RAE in the anterior precordial leads (V1-V3) (48% vs 5%, P < .001) and meet criteria for right ventricular hypertrophy (22% vs 6%, P = .023). CONCLUSION: Our findings show that RAE on ECG has a low PPV for RAE on echocardiogram in previously healthy young patients. The highest yield for RAE on echocardiogram was observed in patients who were <1 year of age, had RAE in the anterior precordial leads, or displayed right ventricular hypertrophy on ECG.

Ferrostatin-1 Blunts Right Ventricular Hypertrophy and Dysfunction in Pulmonary Arterial Hypertension by Suppressing the HMOX1/GSH Signaling.

Ferroptosis plays a critical role in pulmonary arterial hypertension (PAH)-induced right ventricular (RV) dysfunction, but key genes remain largely unclear. We here identified HMOX1 as an essential ferroptosis-related differentially expressed gene in PAH by bioinformatic analysis using FerrDb, GSE119754, and GSE3675 datasets, respectively. Notably, there were marked increases in HMOX1 and iron levels in RV of monocrotaline-induced PAH rats with reduced TAPSE levels. More importantly, treatment with ferrostatin-1 effectively attenuated RV hypertrophy, remodeling, myocardial fibrosis, and dysfunction in PAH rats. In cultured H9C2 cells and primary neonatal rat cardiomyocytes, pretreatment with ferrostatin-1 and knockdown HMOX1 by siRNA strikingly blunted hypoxia-induced promotion of lipid peroxidation, ferroptosis, and cardiomyocyte injury by potentiating glutathione (GSH) and nitric oxide signaling, respectively. In summary, ferrostatin-1 attenuates RV hypertrophy, fibrosis, and dysfunction in PAH by suppressing the HMOX1/GSH signaling. Targeting HMOX1 ferroptosis signaling functions as a potential therapeutic strategy for patients with PAH.

Multi-omic and multispecies analysis of right ventricular dysfunction.

BACKGROUND: Right ventricular failure (RVF) is a leading cause of morbidity and mortality in multiple cardiovascular diseases, but there are no treatments for RVF as therapeutic targets are not clearly defined. Contemporary transcriptomic/proteomic evaluations of RVF are predominately conducted in small animal studies, and data from large animal models are sparse. Moreover, a comparison of the molecular mediators of RVF across species is lacking. METHODS: Transcriptomics and proteomics analyses defined the pathways associated with cardiac magnetic resonance imaging (MRI)-derived values of RV hypertrophy, dilation, and dysfunction in control and pulmonary artery banded (PAB) pigs. Publicly available data from rat monocrotaline-induced RVF and pulmonary arterial hypertension patients with preserved or impaired RV function were used to compare molecular responses across species. RESULTS: PAB pigs displayed significant right ventricle/ventricular (RV) hypertrophy, dilation, and dysfunction as quantified by cardiac magnetic resonance imaging. Transcriptomic and proteomic analyses identified pathways associated with RV dysfunction and remodeling in PAB pigs. Surprisingly, disruptions in fatty acid oxidation (FAO) and electron transport chain (ETC) proteins were different across the 3 species. FAO and ETC proteins and transcripts were mostly downregulated in rats but were predominately upregulated in PAB pigs, which more closely matched the human response. All species exhibited similar dysregulation of the dilated cardiomyopathy and arrhythmogenic right ventricular cardiomyopathy pathways. CONCLUSIONS: The porcine metabolic molecular signature was more similar to human RVF than rodents. These data suggest there may be divergent molecular responses of RVF across species, and pigs may more accurately recapitulate metabolic aspects of human RVF.

Hub gene ELK3-mediated reprogramming lipid metabolism regulates phenotypic switching of pulmonary artery smooth muscle cells to develop pulmonary arterial hypertension induced by PM2.5.

Fine particulate matter (PM2.5) as an environmental pollutant is related with respiratory and cardiovascular diseases. Pulmonary arterial hypertension (PAH) was characterized by incremental pulmonary artery pressure and pulmonary arterial remodeling, leading to right ventricular hypertrophy, and finally cardiac failure and death. The adverse effects on pulmonary artery and the molecular biological mechanism underlying PM2.5-caused PAH has not been elaborated clearly. In the current study, the ambient PM2.5 exposure mice model along with HPASMCs models were established. Based on bioinformatic methods and machine learning algorithms, the hub genes in PAH were screened and then adverse effects on pulmonary artery and potential mechanism was studied. Our results showed that chronic PM2.5 exposure contributed to increased pulmonary artery pressure, pulmonary arterial remodeling and right ventricular hypertrophy in mice. In vitro, PM2.5 induced phenotypic switching in HPASMCs, which served as the early stage of PAH. In mechanism, we investigated that PM2.5-mediated mitochondrial dysfunction could induce phenotypic switching in HPASMCs, which was possibly through reprogramming lipid metabolism. Next, we used machine learning algorithm to identify ELK3 as potential hub gene for mitochondrial fission. Besides, the effect of DNA methylation on ELK3 was further detected in HPASMCs after PM2.5 exposure. The results provided novel directions for protection of pulmonary vasculature injury, against adverse environmental stimuli. This work also provided a new idea for the prevention of PAH, as well as provided experimental evidence for the targeted therapy of PAH.

Chronic hypoxia-induced alterations of the right ventricular myocardium are not aggravated by alimentary obesity in the mouse.

BACKGROUND AND AIMS: Obesity is a risk factor of cardiopulmonary disorders including left and right ventricular dysfunction and pulmonary hypertension (PH), and PH is associated with right ventricular (RV) hypertrophy and failure. Here, we tested the hypothesis that alterations of the RV capillary network under PH induced by chronic hypoxia are aggravated by alimentary obesity, thereby representing a predisposition for subsequent RV dysfunction. METHODS AND RESULTS: Male, 6-week-old C57BL/6N mice were assigned to one of the following groups: control diet (CD), CD/hypoxia (CD-Hyp), high-fat diet (HFD), HFD/hypoxia (HFD-Hyp). Mice were fed CD or HFD for 30 weeks, CD-Hyp and HFD-Hyp mice were exposed to normobaric hypoxia (13 % O2) during the last 3 weeks of the experiments. Hearts were prepared for light and electron microscopy and right atria and RVs were analyzed by design-based stereology. HFD and hypoxia independently increased RV and cardiomyocyte volume. These changes were further enhanced in HFD-Hyp. The ratio between RV and body weights was similar in CD and HFD but enhanced in both hypoxia groups to a similar extent. The total length of capillaries was elevated in proportion with the RV hypertrophy, thus the area of myocardium supplied by an average capillary was similar in all groups. Similarly, the thickness of the capillary endothelium was not altered by HFD or hypoxia. CONCLUSION: In conclusion, in experimental PH capillaries of the RV myocardium showed similar adaptations in lean and obese mice. Thus, under chronic hypoxic conditions, obesity had no adverse effect on the capillarization of the right ventricle.

RGS10 inhibits proliferation and migration of pulmonary arterial smooth muscle cell in pulmonary hypertension via AKT/mTORC1 signaling.

Objective: Excessive proliferation and migration of pulmonary arterial smooth muscle cell (PASMC) is a core event of pulmonary hypertension (PH). Regulators of G protein signaling 10 (RGS10) can regulate cellular proliferation and cardiopulmonary diseases. We demonstrate whether RGS10 also serves as a regulator of PH.Methods: PASMC was challenged by hypoxia to induce proliferation and migration. Adenovirus carrying Rgs10 gene (Ad-Rgs10) was used for external expression of Rgs10. Hypoxia/SU5416 or MCT was used to induce PH. Right ventricular systolic pressure (RVSP) and right ventricular hypertrophy index (RVHI) were used to validate the establishment of PH model.Results: RGS10 was downregulated in hypoxia-challenged PASMC. Ad-Rgs10 significantly suppressed proliferation and migration of PASMC after hypoxia stimulus, while silencing RGS10 showed contrary effect. Mechanistically, we observed that phosphorylation of S6 and 4E-Binding Protein 1 (4EBP1), the main downstream effectors of mammalian target of rapamycin complex 1 (mTORC1) as well as phosphorylation of AKT, the canonical upstream of mTORC1 in hypoxia-induced PASMC were negatively modulated by RGS10. Both recovering mTORC1 activity and restoring AKT activity abolished these effects of RGS10 on PASMC. More importantly, AKT activation also abolished the inhibitory role of RGS10 in mTORC1 activity in hypoxia-challenged PASMC. Finally, we also observed that overexpression of RGS10 in vivo ameliorated pulmonary vascular wall thickening and reducing RVSP and RVHI in mouse PH model.Conclusion: Our findings reveal the modulatory role of RGS10 in PASMC and PH via AKT/mTORC1 axis. Therefore, targeting RGS10 may serve as a novel potent method for the prevention against PH."

Right ventricular global strain in patients with hypertrophic cardiomyopathy with and without right ventricular hypertrophy.

PURPOSE: Regardless of whether there are morphological abnormalities of right ventricle in hypertrophic cardiomyopathy (HCM) patients, the exact contribution of right ventricular (RV) global strains remains unresolved. We aimed to study the prognostic value of RV global strains in HCM patients with and without RV hypertrophy (RVH). METHOD: A total of 358 HCM patients who underwent the CMR examination and carried out the follow-up were finally included in this retrospective study. The endpoint was a composite of all-cause mortality, aborted SCD, and heart failure readmission. RV hypertrophy (RVH) was defined as maximal RVWT ≥ 5 mm at end-diastole. RV global strains (RV global longitudinal strain (GLS) and RV global circumferential strain (GCS) were measured in HCM patients by cardiac MRI feature tracking technique. The intraobserver and interobserver reproducibility were evaluated. Receiver-operating characteristic curves and Kaplan-Meier curves, cox proportional hazards regression, Likelihood ratio test and Integrated Discrimination Improvement (IDI) analysis were performed. P-value were corrected for multiple testing when using many covariables by a false discovery rate adjustment. RESULTS: Over a median follow-up of 25 (range 3-54) months, 49 patients reached the composite endpoints. HCM patients were divided into the RVH group and non-RVH groups. In the multivariate cox proportional hazards regression, after adjusting multiple clinical and imaging variables, RV GLS and RV GCS were independently associated with the composite endpoints in the RVH group (HR: 1.123; 95 % CI: 1.048-1.205; P = 0.002) and non-RVH group (HR: 1.174; 95 % CI: 1.031-1.337; P = 0.015), respectively. And The IDI index of models improved when adding RV GLS (IDI = 0.030, p < 0.001) and RV GLS (IDI = 0.056, p = 0.020), respectively. CONCLUSIONS: RV GLS and RV GCS are independent predictors of HCM with RVH and without RVH, respectively. RV GLS in the RVH group and RV GCS in the non-RVH group provide additional values for predicting the risk of adverse events.

[Quercetin improves pulmonary arterial hypertension in rats by regulating the HMGB1/RAGE/NF-κB pathway].

OBJECTIVE: To explore the mechanism through which quercetin improves pulmonary arterial hypertension (PAH). METHODS: Rat models of hypoxic pulmonary hypertension were established by exposure to hypoxia for 8-10 h each day (6 days a week for 4 weeks), and before each hypoxic exposure, the rats were given intragastric administration of 100 mg/kg quercetin or saline. After the treatments, the right ventricular systolic pressure (RVSP) and pulmonary artery systolic pressure of the rats were recorded. The right ventricular hypertrophy index (RVHI) was measured to evaluate right ventricular hypertrophy. HE staining was used to observe the remodeling of the pulmonary arterioles. The right cardiac function of the rats was evaluated by ultrasound. The protein levels of HMGB1, RAGE, NF-κB, Bax, Bcl-2 and cleaved caspase-3 in the lung tissue of the rats were detected using Western blotting. RESULTS: Compared with the rats maintained in normoxia, the rats with chronic hypoxic exposure showed significantly increased RVHI and RVSP (P<0.01), which were obviously lowered by quercetin treatment (P<0.01). HE staining showed significant pulmonary artery wall thickening with reduced lumen diameter in hypoxia group, and quercetin treatment effectively improved pulmonary vascular remodeling. Ultrasound examination revealed a significantly increased RVFW and a lowered PAT/PET ratio in hypoxia group (P<0.01), and such changes were ameliorated by quercetin treatment (P<0.01). Chronic hypoxia significantly increased the protein expressions of HMGB1 (P<0.01), RAGE, NF-κB and Bcl-2 (P<0.01) and lowered the protein expressions of Bax and cleaved caspase-3 (P<0.01); Quercetin treatment obviously lowered the protein expressions of HMGB1, NF-κB (P<0.05), RAGE (P<0.01) and (P<0.05) and increased the expressions of Bax and cleaved caspase-3 in the rat models (P<0.01). CONCLUSION: Quercetin improves pulmonary hypertension in rats possibly by promoting apoptosis through the HMGB1/RAGE/NF-κB pathway.

Unrepaired tetralogy of Fallot in a 71 years old woman: A case report and review of the literature.

Tetralogy of Fallot (ToF) is the most common cyanotic congenital heart disease (CHD) in infants. The four components that constitute ToF are an overriding aorta over the crest of the interventricular septum, obstruction in the right ventricular outflow tract, right ventricular hypertrophy, and a typically large non-restricted ventricular septal defect. ToF may also be associated with other extracardiac abnormalities, including patent ductus arteriosus or multiple aortopulmonary collateral arteries, which can impact the patient's survival. Patients with unoperated ToF rarely reach adulthood, and it is extremely rare to discover undiagnosed ToF in individuals over 60 years old. In this report, we describe an unusual case of a woman with unrepaired ToF who survived until the age of 71. She was fairly asymptomatic until the 7th decade of her life and complained only of dyspnea on exertion. The patient declined corrective cardiac surgery and preferred conservative management.

Copaiba oil improves pulmonary nitric oxide bioavailability in monocrotaline-treated rats.

Oxidative stress is involved in increased pulmonary vascular resistance (PVR) and right ventricular (RV) hypertrophy, characteristics of pulmonary arterial hypertension (PAH). Copaiba oil, an antioxidant compound, could attenuate PAH damage. This study's aim was to determine the effects of copaiba oil on lung oxidative stress, PVR, and mean pulmonary arterial pressure (mPAP) in the monocrotaline (MCT) model of PAH. Male Wistar rats (170 g, n = 7/group) were divided into four groups: control, MCT, copaiba oil, and MCT + copaiba oil (MCT-O). PAH was induced by MCT (60 mg/kg i.p.) and, after 1 week, the treatment with copaiba oil (400 mg/kg/day gavage) was started for 14 days. Echocardiographic and hemodynamic measurements were performed. RV was collected for morphometric evaluations and lungs and the pulmonary artery were used for biochemical analysis. Copaiba oil significantly reduced RV hypertrophy, PVR, mPAP, and antioxidant enzyme activities in the MCT-O group. Moreover, increased nitric oxide synthase and decreased NADPH oxidase activities were observed in the MCT-O group. In conclusion, copaiba oil was able to improve the balance between nitric oxide and reactive oxygen species in lungs and the pulmonary artery and to reduce PVR, which could explain a decrease in RV hypertrophy in this PAH model.