Cutaneous polyarteritis nodosa and pulmonary arterial hypertension: An unexpected liaison. A case report.

BACKGROUND: Cutaneous polyarteritis nodosa (cPAN) is a form of medium-sized vessel necrotizing vasculitis. It is a rare, skin-limited variant of polyarteritis nodosa, characterized by dermal and subcutaneous tissue involvement. The most common findings in cPAN include digital gangrene, livedo reticularis, and tender subcutaneous nodules. However, while limited to the skin, cPAN results in significant morbidity and mortality due to the accompanying skin ischemia and necrosis, such that patients are vulnerable to superinfection. Here, we describe a unique presentation of cPAN associated with pulmonary arterial hypertension (PAH). METHODS: A 78-year-old female presented with digital ischemia and leg ulcers associated with PAH. Skin biopsy showed necrotizing fibrinoid necrosis of the small- and middle-sized vessels of the dermis. A diagnosis of cPAN and PAH was made. The patient was treated with glucocorticoids, vasodilators, and cyclophosphamide. RESULTS: She died due to severe sepsis complications. CONCLUSION: To date, this is the first case report describing the association between cPAN and PAH. In this case, PAH is a complication of the cutaneous vasculitides suggesting that vasculopathy could play a role in the pathophysiology of PAH. However, the underlying pathophysiological mechanisms still have to be firmly established.

Macrophage-derived inflammation promotes pulmonary vascular remodeling in hypoxia-induced pulmonary arterial hypertension mice.

The role of inflammation in pulmonary hypertension is gradually gaining increasing research attention. However, no previous study has evaluated the characteristics of inflammation during chronic hypoxia-induced pulmonary hypertension. Therefore, the aim of this study was to investigate the characteristics of the inflammatory process involved in hypoxia-induced pulmonary hypertension in mice. The current study evaluated from day 4 to day 28 of hypoxia, the PAAT and PAAT/PET decreased, accompanied by pulmonary vascular remodeling and right ventricular hypertrophy, as well as increased numbers of CD68 macrophages. The expression of the pro-inflammatory factors IL-1ß and IL-33 increased, but decreased on day 28. The expression of IL-12 increased from day 4 to day 28, whereas that of the anti-inflammatory factor IL-10 in lung tissue decreased. Furthermore, the expression of the IL-33/ST2 signaling pathway also increased over time under hypoxic conditions. In conclusion, pulmonary artery remodeling in HPH mice worsens progressively in a time-dependent manner, with inflammatory cell infiltration predominating in the early stage and pulmonary vascular remodeling occurring in the later stage.

Regional Variation in Pulmonary Arterial Hypertension in the United States: The Pulmonary Hypertension Association Registry.

Rationale: Pulmonary arterial hypertension (PAH) is a heterogeneous disease within a complex diagnostic and treatment environment. Other complex heart and lung diseases have substantial regional variation in characteristics and outcomes; however, this has not been previously described in PAH. Objectives: To identify baseline differences between U.S. census regions in the characteristics and outcomes for participants in the Pulmonary Hypertension Association Registry (PHAR). Methods: Adults with PAH were divided into regional groups (Northeast, South, Midwest, and West), and baseline differences between census regions were presented. Kaplan-Meier survival analyses and Cox proportional hazards were used to estimate the association between region and mortality in unadjusted and adjusted models. Results: Substantial differences by census regions were seen in age, race, ethnicity, marital status, employment, insurance payor breakdown, active smoking, and current alcohol use. Differences were also seen in PAH etiology and baseline 6-minute walk distance test results. Treatment characteristics varied by census region, and mortality appeared to be lower in PHAR participants in the West (hazard ratio, 0.60; 95% confidence interval, 0.43-0.83, P = 0.005). This difference was not readily explained by differences in demographic characteristics, PAH etiology, baseline severity, baseline medication regimen, or disease prevalence. Conclusions: The present study suggests significant regional variation among participants at accredited pulmonary vascular disease centers in multiple baseline characteristics and mortality. This variation may have implications for clinical research planning and represent an important focus for further study to better understand whether there are remediable care aspects that can be addressed in the pursuit of providing equitable care in the United States.

Clinical characteristics and risk factors for primary Sjögren's syndrome complicated with pulmonary arterial hypertension. / åŽŸå‘æ€§å¹²ç‡¥ç»¼åˆå¾åˆå¹¶è‚ºåŠ¨è„‰é«˜åŽ‹çš„ä¸´åºŠç‰¹å¾å’Œå±é™©å› ç´ .

OBJECTIVES: Primary Sjögren's syndrome (pSS) is involved in pulmonary tissue. Pulmonary arterial hypertension (PAH) is one of the pulmonary complications caused by pSS. This study aims to investigate the clinical characteristics and risk factors for pSS complicated with PAH. METHODS: We retrospectively analyzed 165 patients in the Second Xiangya Hospital of Central South University. They were divided into a pSS-PAH group (n=86) and a pSS group (n=79) according to pulmonary artery pressure detected by color doppler echocardiography. The clinical characteristics, laboratory test indexes, and risk factors were compared between the 2 groups. RESULTS: Among 165 patients with pSS, 86 patients (52.12%) had PAH. Females were 79 (91.90%) patients in the pSS-PAH group, more than males. The patients in the pSS-PAH group were older than those in the pSS group (all P<0.05). The incidence of keratoconjunctivitis, alopecia, Raynaud's phenomenon, cough, chest tightness, shortness of breath, and dry skin was higher (all P<0.05), and the incidence of pulmonary infection, pulmonary cystic degeneration, respiratory failure, osteoporosis, arteriosclerosis, and hypertension were higher in the pSS-PAH group than those in the pSS group (all P<0.05). The laboratory indicators of pulmonary artery diameter, right atrium diameter, right ventricular contractile diameter and pulmonary artery systolic pressure were higher in the pSS-PAH group than those in the pSS group (all P<0.05), and the positive rates of anti-nuclear antibody, anti-SSA antibody, and anti-Ro-52 antibody were higher (all P<0.05). The incidence of restrictive ventilatory dysfunction and decreased lung diffusion volume in the pSS-PAH group was higher than that in the pSS group (both P<0.05). Advanced age (OR=1.094, 95% CI 1.053 to 1.137, P<0.001), concomitant keratoconjunctivitis (OR=2.075, 95% CI 1.054 to 4.088, P=0.035), hair loss (OR=2.655, 95% CI 1.368 to 5.152, P=0.004), dry skin (OR=2.696, 95% CI 1.364 to 5.332, P=0.004), high pulmonary artery systolic pressure (OR=1.185, 95% CI 1.125 to 1.248, P<0.001), respiratory failure (OR=2.279, 95% CI 1.137 to 4.570, P=0.020), osteoporosis (OR=2.087, 95% CI 1.025 to 4.248, P=0.043), atherosclerosis (OR=2.251, 95% CI 1.146 to 4.423, P=0.018), hypertension (OR=2.370, 95% CI 1.190 to 4.718, P=0.014), the increased antinuclear antibody (OR=2.155, 95% CI 1.094 to 4.245, P=0.026), the increased anti-SSA antibody (OR=2.565, 95% CI 1.292 to 5.091, P=0.007), the increased anti-RO-52 antibody (OR=2.623, 95% CI 1.278 to 5.383, P=0.009), and the decreased lung dispersion (OR=2.602, 95% CI 1.386 to 4.884, P=0.003), were all risk factors for PAH in pSS patients. CONCLUSIONS: The incidence of pSS-PAH is high in this study. The advanced age, elevated pulmonary artery systolic pressure, concomitant keratoconjunctivitis, alopecia, dry skin, respiratory failure, osteoporosis, arteriosclerosis, and hypertension, increased anti-nuclear antibody, anti-SSA antibody, and anti-Ro-52 antibody, and decreased pulmonary dispersion suggest that the risk of PAH is significantly increased in patients with pSS.

Advances in the discovery of drugs that treat pulmonary arterial hypertension.

INTRODUCTION: Distal pulmonary arterial remodeling and elevated pulmonary vascular resistance are characteristic of pulmonary arterial hypertension (PAH). Current approved vasodilator-specific PAH therapy that includes phosphodiesterase-5 inhibitors, soluble guanylate cyclase stimulators, endothelin receptor antagonists, and prostanoids has demonstrated dramatic enhancement in functional capacity, quality of life, and invasive hemodynamics. However, none of these treatments are curative, underscoring the need to identify new pathophysiologic signaling pathways. AREAS COVERED: The author provides a comprehensive review on current knowledge and recent development in the understanding of PAH. Furthermore, the author discusses PAH potential genetic causes as well as novel molecular signaling pathways. This article also reviews the currently approved PAH specific therapy based on pivotal clinical trials and ongoing clinical trials using novel compounds that specifically target PAH pathogenesis. EXPERT OPINION: The discovery of novel signaling pathways - growth factors, tyrosine kinases, BMPs, estrogen, and serotonin - involved in the PAH pathobiology will lead within the next 5 years to the approval of new therapeutic agents targeting these different pathways. If proven beneficial, these new agents may reverse or at least prevent the progression of this devastating and lethal disease.

Wnt7a deficit is associated with dysfunctional angiogenesis in pulmonary arterial hypertension.

INTRODUCTION: Pulmonary arterial hypertension (PAH) is characterised by loss of microvessels. The Wnt pathways control pulmonary angiogenesis but their role in PAH is incompletely understood. We hypothesised that Wnt activation in pulmonary microvascular endothelial cells (PMVECs) is required for pulmonary angiogenesis, and its loss contributes to PAH. METHODS: Lung tissue and PMVECs from healthy and PAH patients were screened for Wnt production. Global and endothelial-specific Wnt7a -/- mice were generated and exposed to chronic hypoxia and Sugen-hypoxia (SuHx). RESULTS: Healthy PMVECs demonstrated >6-fold Wnt7a expression during angiogenesis that was absent in PAH PMVECs and lungs. Wnt7a expression correlated with the formation of tip cells, a migratory endothelial phenotype critical for angiogenesis. PAH PMVECs demonstrated reduced vascular endothelial growth factor (VEGF)-induced tip cell formation as evidenced by reduced filopodia formation and motility, which was partially rescued by recombinant Wnt7a. We discovered that Wnt7a promotes VEGF signalling by facilitating Y1175 tyrosine phosphorylation in vascular endothelial growth factor receptor 2 (VEGFR2) through receptor tyrosine kinase-like orphan receptor 2 (ROR2), a Wnt-specific receptor. We found that ROR2 knockdown mimics Wnt7a insufficiency and prevents recovery of tip cell formation with Wnt7a stimulation. While there was no difference between wild-type and endothelial-specific Wnt7a -/- mice under either chronic hypoxia or SuHx, global Wnt7a +/- mice in hypoxia demonstrated higher pulmonary pressures and severe right ventricular and lung vascular remodelling. Similar to PAH, Wnt7a +/- PMVECs exhibited an insufficient angiogenic response to VEGF-A that improved with Wnt7a. CONCLUSIONS: Wnt7a promotes VEGF signalling in lung PMVECs and its loss is associated with an insufficient VEGF-A angiogenic response. We propose that Wnt7a deficiency contributes to progressive small vessel loss in PAH.

Identification of potential serum biomarkers for congenital heart disease children with pulmonary arterial hypertension by metabonomics.

BACKGROUND: Pulmonary arterial hypertension is a common complication in patients with congenital heart disease. In the absence of early diagnosis and treatment, pediatric patients with PAH has a poor survival rate. Here, we explore serum biomarkers for distinguishing children with pulmonary arterial hypertension associated with congenital heart disease (PAH-CHD) from CHD. METHODS: Samples were analyzed by nuclear magnetic resonance spectroscopy-based metabolomics and 22 metabolites were further quantified by ultra-high-performance liquid chromatography-tandem mass spectroscopy. RESULTS: Serum levels of betaine, choline, S-Adenosyl methionine (SAM), acetylcholine, xanthosine, guanosine, inosine and guanine were significantly altered between CHD and PAH-CHD. Logistic regression analysis showed that combination of serum SAM, guanine and N-terminal pro-brain natriuretic peptide (NT-proBNP), yielded the predictive accuracy of 157 cases was 92.70% with area under the curve of the receiver operating characteristic curve value of 0.9455. CONCLUSION: We demonstrated that a panel of serum SAM, guanine and NT-proBNP is potential serum biomarkers for screening PAH-CHD from CHD.

Human Resistin Induces Cardiac Dysfunction in Pulmonary Hypertension.

Background Cardiac failure is the primary cause of death in most patients with pulmonary arterial hypertension (PH). As pleiotropic cytokines, human resistin (Hresistin) and its rodent homolog, resistin-like molecule α, are mechanistically critical to pulmonary vascular remodeling in PH. However, it is still unclear whether activation of these resistin-like molecules can directly cause PH-associated cardiac dysfunction and remodeling. Methods and Results In this study, we detected Hresistin protein in right ventricular (RV) tissue of patients with PH and elevated resistin-like molecule expression in RV tissues of rodents with RV hypertrophy and failure. In a humanized mouse model, cardiac-specific Hresistin overexpression was sufficient to cause cardiac dysfunction and remodeling. Dilated hearts exhibited reduced force development and decreased intracellular Ca2+ transients. In the RV tissues overexpressing Hresistin, the impaired contractility was associated with the suppression of protein kinase A and AMP-activated protein kinase. Mechanistically, Hresistin activation triggered the inflammation mediated by signaling of the key damage-associated molecular pattern molecule high-mobility group box 1, and subsequently induced pro-proliferative Ki67 in RV tissues of the transgenic mice. Intriguingly, an anti-Hresistin human antibody that we generated protected the myocardium from hypertrophy and failure in the rodent PH models. Conclusions Our data indicate that Hresistin is expressed in heart tissues and plays a role in the development of RV dysfunction and maladaptive remodeling through its immunoregulatory activities. Targeting this signaling to modulate cardiac inflammation may offer a promising strategy to treat PH-associated RV hypertrophy and failure in humans.

Metastatic pancreatic cancer presenting with pulmonary arterial hypertension.

Chronic cough is one of the most common symptoms encountered in respiratory clinics. It has a variety of differential diagnoses, and without a clear algorithmic approach, the final diagnosis can be overlooked. In this case report, we present a unique case of metastatic pancreatic cancer presented as chronic cough.

Patent ductus arteriosus and the risk of bronchopulmonary dysplasia-associated pulmonary hypertension.

BACKGROUND: The aim of the study was to determine whether prolonged exposure to a moderate/large patent ductus arteriosus left-to-right shunt (PDA) increases the risk of late (beyond 36 weeks) pulmonary hypertension (BPD-PH) and pulmonary vascular disease (BPD-PVD) during the neonatal hospitalization in preterm infants (<28 weeks' gestation) with bronchopulmonary dysplasia (BPD). METHODS: All infants requiring respiratory support ≥36 weeks had systematic echocardiographic evaluations for BPD-PH at planned intervals. Infants were classified as having either flow-associated BPD-PH (BPD-flow-PH) or BPD-PVD. RESULTS: 256 infants survived ≥36 weeks: 105 had NO BPD (were off respiratory support by 36 weeks); 151 had BPD. 22/151 had BPD-PH (12/22 had BPD-flow-PH from a PDA that persisted beyond 36 weeks; 10/22 had BPD-PVD). Moderate/large PDA shunts that persisted beyond 36 weeks were significantly associated with an increased incidence of BPD-PH due to BPD-flow-PH. We found no association between the duration of PDA exposure and the incidence of BPD-PVD. CONCLUSIONS: Moderate/large PDA shunts increase the risk of flow-associated BPD-PH when present beyond 36 weeks. Although term infants with PDA-congenital heart disease can develop pulmonary vascular remodeling and PVD after months of PDA exposure, we found no echocardiographic evidence in preterm infants that prolonged PDA exposure increases the incidence of BPD-PVD during the neonatal hospitalization. IMPACT: In our study, preterm infants (<28 weeks' gestation) with bronchopulmonary dysplasia (BPD) had a 15% incidence of pulmonary hypertension (PH) beyond 36 weeks' postmenstrual age as a comorbidity. Moderate/large patent ductus arteriosus (PDA) shunts increased the risk of flow-associated PH when present beyond 36 weeks. Although months of prolonged PDA exposure can cause pulmonary vascular remodeling and pulmonary vascular disease (PVD) in term infants with PDA-congenital heart disease, we found no echocardiographic evidence for an association between the duration of PDA exposure and the incidence of late PVD during the neonatal hospitalization in preterm infants with BPD.

Intermittent Hypoxemia and Bronchopulmonary Dysplasia with Pulmonary Hypertension in Preterm Infants.

Rationale: Bedside biomarkers that allow early identification of infants with bronchopulmonary dysplasia-associated pulmonary hypertension (BPD-PH) are critically important, given the higher risk of death in these infants. Objectives: We hypothesized that infants with BPD-PH have patterns of intermittent hypoxemia (IH) that differ from infants with BPD without PH. Methods: We conducted a matched case-control study of extremely preterm infants from 22 weeks 0 days to 28 weeks 6 days born between 2018 and 2020 at the University of Alabama at Birmingham. BPD-PH status was determined using echocardiographic data performed after postnatal Day 28. Physiologic data were compared between infants with BPD-PH (cases) and BPD alone (control subjects). Receiver operating characteristic (ROC) analysis estimated the predictive ability of cumulative hypoxemia, desaturation frequency, and duration of intermittent hypoxemic events in the week preceding echocardiography to discriminate between cases and control subjects. Measurements and Main Results: Forty infants with BPD-PH were compared with 40 infants with BPD alone. Infants with and without PH had a similar frequency of IH events, but infants with PH had more prolonged hypoxemic events for desaturations below 80% (7 s vs. 6 s; P = 0.03) and 70% (105 s vs. 58 s; P = 0.008). Among infants with BPD-PH, infants who died had longer hypoxemic events below 70% (145 s vs. 72 s; P = 0.01). Using the duration of hypoxemic events below 70%, the areas under the ROC curves for diagnosis of BPD-PH and death in BPD-PH infants were 0.71 and 0.77, respectively. Conclusions: Longer duration of intermittent hypoxemic events was associated both with a diagnosis of BPD-PH and with death among infants with BPD-PH.

Circulating markers of inflammation and angiogenesis and clinical outcomes across subtypes of pulmonary arterial hypertension.

BACKGROUND: Subtypes of pulmonary arterial hypertension (PAH) differ in both fundamental disease features and clinical outcomes. Angiogenesis and inflammation represent disease features that may differ across subtypes and are of special interest in connective tissue disease-associated PAH (CTD-PAH). We compared inflammatory and angiogenic biomarker profiles across different etiologies of PAH and related them to clinical outcomes. METHODS: Participants with idiopathic PAH, CTD-PAH, toxin-associated PAH (tox-PAH), or congenital heart disease-associated PAH (CHD-PAH) were enrolled into a prospective observational cohort. Baseline serum concentrations of 33 biomarkers were related to 3-year mortality, echocardiogram, REVEAL score, and 6-minute walk distance (6MWD). Findings were validated using plasma proteomic data from the UK PAH Cohort Study. RESULTS: One hundred twelve patients were enrolled: 45 idiopathic, 27 CTD-PAH, 20 tox-PAH, and 20 CHD-PAH. Angiogenic and inflammatory biomarkers were distinctly elevated within the CTD-PAH cohort. Six biomarkers were associated with mortality within the entire PAH cohort: interleukin-6 (IL-6, HR:1.6, 95% CI:1.18-2.18), soluble fms-like tyrosine kinase 1 (sFlt-1, HR:1.35, 95% CI:1.02-1.80), placental growth factor (PlGF, HR:1.55, 95% CI:1.07-2.25), interferon gamma-induced protein 10 (IP-10, HR:1.44, 95% CI:1.04-1.99), tumor necrosis factor-beta (TNF-ß, HR:1.81, 95% CI:1.11-2.95), and NT-proBNP (HR:2.19, 95% CI:1.52-3.14). Only IL-6 and NT-proBNP remained significant after controlling for multiple comparisons. IL-6, IP-10, and sFlt-1 significantly associated with mortality in CTD-PAH, but not non-CTD-PAH subgroups. In the UK cohort, IP-10, PlGF, TNF-ß, and NT-proBNP significantly associated with 5-year survival. CONCLUSION: Levels of angiogenic and inflammatory biomarkers are elevated in CTD-PAH, compared with other etiologies of PAH, and may correlate with clinical outcomes including mortality.

Patent Ductus Arteriosus and Development of Bronchopulmonary Dysplasia-associated Pulmonary Hypertension.

Rationale: Extremely preterm infants with evolving bronchopulmonary dysplasia (BPD) are at risk for development of BPD-associated pulmonary hypertension (BPD-PH). A patent ductus arteriosus (PDA) shunt may be a modifiable risk factor for BPD-PH development. Objective: To determine whether the presence and duration of ductus arteriosus patency differs between extremely preterm infants with and without BPD-PH. Methods: We conducted a retrospective case-control study among preterm infants of gestational age 22 weeks, 0 days, to 28 weeks, 6 days, who remained on respiratory support on postnatal day 28 at the University of Alabama at Birmingham from 2017 to 2020. Infants who were diagnosed with PH (cases) by echocardiography were compared with infants without PH (control subjects). Data from echocardiograms performed during the hospitalization after postnatal day 28 were included. Logistic regression adjusted for covariates that differed significantly between groups. A probit analysis related the duration of ductal patency to the development of BPD-PH. Measurements and Main Results: A total of 138 infants developed BPD alone, and 82 infants developed BPD-PH. After adjustment for differing covariates between groups, both PDA (adjusted odds ratio, 4.29; 95% confidence interval, 1.89-9.77) and moderate to large PDA (adjusted odds ratio, 4.15; 95% confidence interval, 1.78-9.64) remained significantly related to BPD-PH at discharge. By probit analysis, each additional month of PDA and hemodynamically significant PDA exposure was associated with an increased probability for the composite outcome of BPD-PH at discharge or death with coefficients of 0.40 (P < 0.001) and 0.45 (P < 0.001), respectively. Conclusions: In extremely preterm infants on respiratory support on postnatal day 28, both the presence of and a longer duration of ductus arteriosus patency were associated with the development of BPD-PH.

Lung Volume Reduction Surgery Reduces Pulmonary Arterial Hypertension Associated With Severe Lung Emphysema and Hypercapnia.

Lung volume reduction surgery (LVRS) represents a standard surgical approach for patients with severe pulmonary emphysema. One of the relevant risk factors for LVRS is the presence of pulmonary arterial hypertension (PAH). The aim of this study is to assess the postoperative changes in pulmonary arterial pressure (PAP) after LVRS for patients with severe pulmonary emphysema compared with preoperative measures. N = 61 consecutive patients with severe pulmonary emphysema and preoperative evidence for PAH (pulmonary arterial systolic pressure [PASP] ≥ 35 mmHg) were prospectively included into this study. In all patients, thoracoscopic LVRS was performed. PASP was assessed by echocardiography before surgery, early postoperatively, and 3 months after surgery. Data were prospectively recorded and analyzed retrospectively. Primary end points were the postoperative changes in PASP as well as the 90 day mortality rate. Secondary endpoints included: pulmonary function test, exercise capacity, quality of life, and dyspnea symptoms (Borg scale). Early after surgery, a significant reduction in PASP was observed at the day of discharge and at 3 month follow-up. In n = 34 patients, no tricuspid valve regurgitation was detectable anymore suggesting normal PAP. In n = 3 patients, venovenous extracorporeal lung support (VV ECLS) was already implemented preoperatively. In the remaining cases, VV ECLS was applied intraoperatively and continued postoperatively. Mean duration of postoperative ECLS support was 2 days. Four patients died due to acute right heart failure, two patients from sepsis with multiorgan failure, and one patient from acute pulmonary embolism. Ninety day mortality was 11.5 %. A significant improvement was postoperatively observed regarding the performance status, dyspnea scale, as well as quality of life. This study suggests a beneficial effect of LVRS on PAP, which may ultimately help to protect and stabilize right ventricular function. Further studies, implementing pre- and postoperative right heart catheterizations including invasive PAP evaluation, are necessary to support the findings in this study in greater detail.

Dapagliflozin reduces the vulnerability of rats with pulmonary arterial hypertension-induced right heart failure to ventricular arrhythmia by restoring calcium handling.

BACKGROUND: Malignant ventricular arrhythmia (VA) is a major contributor to sudden cardiac death (SCD) in patients with pulmonary arterial hypertension (PAH)-induced right heart failure (RHF). Recently, dapagliflozin (DAPA), a sodium/glucose cotransporter-2 inhibitor (SGLT2i), has been found to exhibit cardioprotective effects in patients with left ventricular systolic dysfunction. In this study, we examined the effects of DAPA on VA vulnerability in a rat model of PAH-induced RHF. METHODS: Rats randomly received monocrotaline (MCT, 60 mg/kg) or vehicle via a single intraperitoneal injection. A day later, MCT-injected rats were randomly treated with placebo, low-dose DAPA (1 mg/kg/day), or high-dose (3 mg/kg/day) DAPA orally for 35 days. Echocardiographic analysis, haemodynamic experiments, and histological assessments were subsequently performed to confirm the presence of PAH-induced RHF. Right ventricle (RV) expression of calcium (Ca2+) handling proteins were detected via Western blotting. RV expression of connexin 43 (Cx43) was determined via immunohistochemical staining. An optical mapping study was performed to assess the electrophysiological characteristics in isolated hearts. Cellular Ca2+ imaging from RV cardiomyocytes (RVCMs) was recorded using Fura-2 AM or Fluo-4 AM. RESULTS: High-dose DAPA treatment attenuated RV structural remodelling, improved RV function, alleviated Cx43 remodelling, increased the conduction velocity, restored the expression of key Ca2+ handling proteins, increased the threshold for Ca2+ and action potential duration (APD) alternans, decreased susceptibility to spatially discordant APD alternans and spontaneous Ca2+ events, promoted cellular Ca2+ handling, and reduced VA vulnerability in PAH-induced RHF rats. Low-dose DAPA treatment also showed antiarrhythmic effects in hearts with PAH-induced RHF, although with a lower level of efficacy. CONCLUSION: DAPA administration reduced VA vulnerability in rats with PAH-induced RHF by improving RVCM Ca2+ handling.

Surgical management of giant pulmonary artery aneurysms in patients with severe pulmonary arterial hypertension.

BACKGROUND AND AIM: Giant aneurysm of the pulmonary artery (PAA) is an extremely rare condition that may develop in patients with pulmonary arterial hypertension (PAH) which may be complicated by rupture, dissection or intravascular thrombus formation. The aim of this study was to examine available literature with regard to surgical strategies in patients undergoing transplantation for PAH with PAA. RESULTS: These patients were traditionally considered for heart-lung transplantation but more recently, there have been reports of successful lung transplantation with reconstruction of the pulmonary artery. CONCLUSIONS: Unless there is a mandatory indication for heart-lung transplantation, patients with PAH and PAA can undergo lung transplantation and reconstruction of the pulmonary artery without compromising the outcome.

Leiomyosarcoma in adrenal gland.

Not required for Clinical Vignette.

Thioredoxin system activation is associated with the progression of experimental pulmonary arterial hypertension.

In addition to being an antioxidant, thioredoxin (Trx) is known to stimulate signaling pathways involved in cell proliferation and to inhibit apoptosis. The aim of this study was to explore the role of Trx in some of these pathways along the progression of monocrotaline (MCT)-induced pulmonary arterial hypertension (PAH). Male rats were first divided into two groups: monocrotaline (MCT - 60 mg/kg i.p.) and control (received saline), that were further divided into three groups: 1, 2, and 3 weeks. Animals were submitted to echocardiographic analysis. Right and left ventricles were used for the measurement of hypertrophy, through morphometric and histological analysis. The lung was prepared for biochemical and molecular analysis. One week after MCT injection, there was an increase in thioredoxin reductase (TrxR) activity, a reduction in glutathione reductase (GR) activity, and an increase in Trx-1 and vitamin D3 up-regulated protein-1 (VDUP-1) expression. Two weeks after MCT injection, there was an increase in VDUP-1, Akt and cleaved caspase-3 activation, and a decrease in Trx-1 and Nrf2 expression. PAH-induced by MCT promoted a reduction in Nrf2 and Trx-1 expression as well as an increase in Akt and VDUP-1 expression after three weeks. The increase in pulmonary vascular resistance was accompanied by increased TrxR activity, suggesting an association between the Trx system and functional changes in the progression of PAH. It seems that Trx-1 activation was an adaptive response to MCT administration to cope with pulmonary remodeling and disease progression, suggesting a potential new target for PAH therapeutics.

Betaine alleviates right ventricular failure via regulation of Rho A/ROCK signaling pathway in rats with pulmonary arterial hypertension.

Pulmonary vascular remodeling was shown to lead to pulmonary arterial hypertension (PAH), further trigger excessive apoptosis of cardiomyocytes, and ultimately cause right ventricular failure (RVF), which involves the activation of Rho A/ROCK signaling pathway. Betaine has been found efficacious for attenuating PAH through its anti-inflammatory effects in our previous research while its effects on RVF due to PAH remains inconclusive. Thus, we attempted to elucidate the protective effects of betaine on PAH, RVF due to PAH as well as the potential mechanisms. To this end, male Sprague Dawley rats received a single subcutaneous injection of monocrotaline (50 mg/kg) to imitate PAH and RVF, and subsequently oral administration of betaine (100, 200, and 400 mg/kg/day). Betaine treatment improved the hemodynamics and histomorphological parameters and echocardiographic changes. Moreover, betaine also alleviated the pulmonary vascular remodeling and cardiomyocyte apoptosis. The mechanisms study revealed that administration of betaine significantly increased the expression of Rho A, ROCK1, and ROCK2. Furthermore, betaine alleviated the changes of its downstream molecules P53, Bcl-2, Bax, phosphorylated MYPT1 (p-MYPT1), total MYPT1 (t-MYPT1), p27kip1, and Cleaved Caspase-3. According to what we observed, this study indicated that betaine treatment could protect RVF due to PAH, which may be achieved through an altered Rho A/ROCK signaling pathway.