Bile acid-induced tissue factor activity in hepatocytes correlates with activation of farnesoid X receptor.

Bile acids (BA) have been found to promote coagulation by increasing tissue factor (TF) activity. The contribution of elevated BA levels and cholestasis to TF decryption within the liver parenchyma and the role of farnesoid X receptor (FXR) in this process remain unclear. We investigated the effects of BA on TF activity and thrombin generation in hepatocytes and correlated these effects with activation of FXR-dependent signaling and apoptosis. HepG2 cells and primary hepatocytes were incubated with chenodeoxycholic acid (CDCA), glycochenodeoxycholic acid (GCDCA), ursodeoxycholic acid (UCDA), or the synthetic FXR agonist GW4064 for 24 h. MTT tests demonstrated cell viability throughout experiments. TF activity was tested via factor Xa generation and thrombin generation was measured by calibrated automated thrombography. Increased TF activity alongside enhanced thrombin generation was observed with CDCA and GW4064 but not with GCDCA and UDCA. TF activity was substantially reduced when FXR activation was blocked with the antagonist DY 268. Quantitative polymerase chain reaction revealed upregulation of FXR target genes only by CDCA and GW4064. Western blot analysis and fluorescence microscopy showed no TF overexpression arguing for TF decryption. Caspase 3 activity measurements and flow cytometric analysis of Annexin V binding showed no signs of apoptosis. Long-term exposure of hepatocytes to nontoxic BA may cause intracellular FXR overstimulation, triggering TF decryption irrespective of the amphiphilic properties of BA. The effect of BA on TF activation correlates with the molecule's ability to enter the cells and activate FXR. TF decryption occurs independently of apoptotic mechanisms.

Recommendations from the Association for European Paediatric and Congenital Cardiology for training in pulmonary hypertension.

Pulmonary hypertension is a complex and progressive condition that is either idiopathic or heritable, or associated with one or multiple health conditions, with or without congenital or acquired cardiovascular disease. Recent developments have tremendously increased the armamentarium of diagnostic and therapeutic approaches in children and young adults with pulmonary hypertension that is still associated with a high morbidity and mortality. These modalities include non-invasive imaging, pharmacotherapy, interventional and surgical procedures, and supportive measures. The optimal, tailored diagnostic and therapeutic strategies for pulmonary hypertension in the young are rapidly evolving but still face enormous challenges: Healthcare providers need to take the patient's age, development, disease state, and family concerns into account when initiating advanced diagnostics and treatment. Therefore, there is a need for guidance on core and advanced medical training in paediatric pulmonary hypertension. The Association for European Paediatric and Congenital Cardiology working group "pulmonary hypertension, heart failure and transplantation" has produced this document as an expert consensus statement; however, all recommendations must be considered and applied in the context of the local and national infrastructure and legal regulations.

Neonatal sepsis leads to early rise of rare serum bile acid tauro-omega-muricholic acid (TOMCA).

BACKGROUND: We investigated 'rare' bile acids (BA) as potential markers in septic neonates. METHODS: 'Rare' (C-6 hydroxylated BA) and 'classical' BA were determined in 102 neonates using high-performance liquid chromatography-high-resolution mass spectrometry (HPLC-HRMS). Four groups according to maturity (full term, FT vs. preterm, PT) and septic status (early-onset neonatal sepsis, EOS vs. CTR; non-septic controls) were formed: FT-CTR; (n = 47), PT-CTR (n = 22), FT-EOS (n = 20), PT-EOS (n = 13). RESULTS: Firstly, FT-CTR had a significant higher amount of 'rare' BA than PT (FT-CTR: 0.5 µmol/L, IQR: 0.3-1.3 vs. PT-CTR: 0.01 µmol/L, IQR 0.01-0.2; p < 0.01). The most common 'rare' BA in FT-CTR were tauro-γ- (TGMCA) and tauro-α-muricholic acid (TAMCA). Secondly, in EOS, absolute 'rare' BA levels were comparable in both gestational age groups (FT-EOS: 0.6 µmol/L, IQR: 0.1-1.6 and PT-EOS: 0.6 µmol/L, IQR: 0.2-1.5). Therefore, EOS had significantly higher median 'rare' BA values than non-septic PT neonates (p < 0.01). In PT and term neonates, the relative amount of tauro-ω-muricholic acid (TOMCA) within the 'rare' BA pool was significantly higher in EOS than in controls (FT-CTR vs. "FT-EOS and PT-CTR vs. PT-EOS; p < 0.01). It was hence the predominant 'rare' BA in EOS. CONCLUSION: TOMCA is an independent factor associated with EOS. It has diagnostic potential.

Mild Acquired von Willebrand Syndrome and Cholestasis in Pediatric and Adult Patients with Fontan Circulation.

Background: Hemodynamic alterations in Fontan patients (FP) are associated with hemostatic dysbalance and Fontan-associated liver disease. Studies of other hepatopathologies indicate an interplay between cholestasis, tissue factor (TF), and von Willebrand factor (VWF). Hence, we hypothesized a relationship between the accumulation of bile acids (BA) and these hemostatic factors in FP. Methods: We included 34 FP (Phenprocoumon n = 15, acetylsalicylic acid (ASA) n = 16). BA were assessed by mass spectrometry. TF activity and VWF antigen (VWF:Ag) were determined by chromogenic assays. VWF collagen-binding activity (VWF:CB) was assessed via ELISA. Results: Cholestasis was observed in 6/34 FP (total BA ≥ 10 µM). BA levels and TF activity did not correlate (p = 0.724). Cholestatic FP had lower platelet counts (p = 0.013) from which 5/6 FP were not treated with ASA. VWF:Ag levels were increased in 9/34 FP and significantly lower in FP receiving ASA (p = 0.044). Acquired von Willebrand syndrome (AVWS) was observed in 10/34-FP, with a higher incidence in cholestatic FP (4/6) (p = 0.048). Conclusions: Cholestasis is unexpectedly infrequent in FP and seems to be less frequent under ASA therapy. Therefore, ASA may reduce the risk of advanced liver fibrosis. FP should be screened for AVWS to avoid bleeding events, especially in cholestatic states.

The Covert Surge: Murine Bile Acid Levels Are Associated With Pruritus in Pediatric Autoimmune Sclerosing Cholangitis.

Objectives: The exact etiology of pruritus in chronic cholestasis is unknown. Pruritus intensity does not correlate with common biochemical indices and there is a lack of biomarkers guiding diagnosis and treatment. We explored profiles of bile acids (BA) and muricholic acids (MCA) as well as autotaxin (ATX) antigen levels as potential circulating biomarkers of pruritus in pediatric patients. Methods: In 27 pediatric cholestatic patients [autoimmune sclerosing cholangitis (ASC) n = 20 (with pruritus n = 6, without pruritus n = 14); progressive familial intrahepatic cholestasis (PFIC) n = 7 (with pruritus n = 5, without pruritus n = 2)] and 23 age-matched controls pruritus was assessed by a visual analog scale of pruritus (PVAS). We obtained profiles of serum human BA including MCA using a mass-spectrometry assay and ATX antigen levels with a commercial ELISA. Results: PFIC and ASC patients exhibited significantly higher BA-, and MCA levels, than healthy controls, but only PFIC patients showed elevated ATX antigen levels higher [median: 1,650 ng/ml, interquartile rang (IQR): 776.9-3,742] compared to controls (median: 315.9 ng/ml, IQR: 251.1-417.2; PFIC p = 0.0003). ASC patients with pruritus showed only a minor increase in total BA (tBA) levels (median: 76.5 µmol/L, IQR: 54.7-205), but strikingly higher T-conjugated BA (median: 16.4 µmol/L, IQR: 8.9-41.4) and total MCA (tMCA) (median: 1.15 µmol/L, IQR: 0.77-2.44) levels compared to ASC patients without pruritus (tBA median: 24.3 µmol/L, IQR: 16.2-80.8; p < 0.0408; T-conjugated BA median: 1.3 µmol/L, IQR: 0.8-4.9; p = 0.0023; tMCA median: 0.30 µmol/L, IQR: 0.13-0.64, p = 0.0033). BA/MCA profiles distinctly differed depending on presence/absence of pruritus. Different from PFIC patients, ATX antigen levels were not significantly elevated in ASC patients with (median: 665.8 ng/ml, IQR: 357.8-1,203) and without pruritus (median: 391.0 ng/ml, IQR: 283.2-485.6). In ASC patients, tBA, tMCA, and ATX antigen levels did not correlate with pruritus severity. Conclusion: Despite the same underlying disease, pediatric ASC patients with pruritus exhibit significantly altered BA profiles and MCA levels compared to ASC patients without pruritus. ATX antigen levels seem to have little diagnostic or prognostic meaning in ASC patients. An increased ATX activity alone seems not to be causal for pruritus genesis in ASC patients. Clinical Trial Registration: [www.drks.de], identifier [DRKS00026913].

Extremely premature infants born at 23-25 weeks gestation are at substantial risk for pulmonary hypertension.

OBJECTIVE: Extremely low gestational age newborns (ELGANs) represent an especially vulnerable population. Herein, we aimed to determine incidence and severity of pulmonary hypertension associated with bronchopulmonary dysplasia (BPD-PH) in extremely immature ELGANs (gestational age: 230/6-256/7 weeks). METHODS: In this prospective observational cohort study, we assessed BPD-PH by means of several echocardiography markers and serum N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels at 3 and 12 months of chronological age. In addition, we analyzed incidence and efficacy of pharmacologic treatment for BPD-PH. RESULTS: At 3 months 15/34 ELGANs had echocardiographic evidence of BPD-PH, while at 12 months of age 6/34 still had PH. PH-targeted therapy consisted of sildenafil monotherapy in 11 and dual oral combination therapy (sildenafil and macitentan) in four ELGANs at 3 and 12 months. CONCLUSION: 44% (15/34) of ELGANs developed BPD-PH. All received PH-targeted pharmacotherapy at 3 months, leading to hemodynamic improvements at 12 months in most infants.

Amino Acid and Phospholipid Metabolism as an Indicator of Inflammation and Subtle Cardiomyopathy in Patients with Marfan Syndrome.

Patients with Marfan syndrome (MFS) have an increased risk of aortic aneurysm formation, dissection and development of a subtle cardiomyopathy. We analyzed amino acid and lipid metabolic pathways in MFS patients, seeking biomarker patterns as potential monitoring tools of cardiovascular risk with deterioration of myocardial function. We assessed myocardial function in 24 adult MFS patients and compared traditional laboratory values and mass spectrometry-based amino acid, phospholipid and acylcarnitine metabolomes in patients with those in healthy controls. Analytes for which values differed between patients and controls were subjected to regression analysis. A high proportion of patients had signs of impaired diastolic function and elevated serum levels of NT-proBNP. Patients had lower serum levels of taurine, histidine and PCaeC42:3 than controls. The evidence of diastolic dysfunction, aortic root dimensions and history of aortic root surgery correlated with NT-proBNP and taurine levels. Alterations in serum levels of metabolism derived analytes link MFS pathophysiology with inflammation, oxidative stress and incipient cardiomyopathy.

Echocardiography for the Assessment of Pulmonary Hypertension and Congenital Heart Disease in the Young.

While invasive assessment of hemodynamics and testing of acute vasoreactivity in the catheterization laboratory is the gold standard for diagnosing pulmonary hypertension (PH) and pulmonary vascular disease (PVD) in children, transthoracic echocardiography (TTE) serves as the initial diagnostic tool. International guidelines suggest several key echocardiographic variables and indices for the screening studies when PH is suspected. However, due to the complex anatomy and special physiological considerations, these may not apply to patients with congenital heart disease (CHD). Misinterpretation of TTE variables can lead to delayed diagnosis and therapy, with fatal consequences, or-on the other hand-unnecessary invasive diagnostic procedures that have relevant risks, especially in the pediatric age group. We herein provide an overview of the echocardiographic workup of children and adolescents with PH with a special focus on children with CHD, such as ventricular/atrial septal defects, tetralogy of Fallot or univentricular physiology. In addition, we address the use of echocardiography as a tool to assess eligibility for exercise and sports, a major determinant of quality of life and outcome in patients with PH associated with CHD.

Selexipag for the treatment of children with pulmonary arterial hypertension: First multicenter experience in drug safety and efficacy.

BACKGROUND: The European Pediatric Pulmonary Vascular Disease Network (EPPVDN) investigated the safety and efficacy of add-on selexipag, an oral prostacyclin receptor agonist approved for pulmonary arterial hypertension (PAH) in adults, in the largest, exploratory pediatric cohort to date. METHODS: This is a prospective observational study of 15 consecutive children with PAH, treated with oral add-on selexipag at 3 centers. Most patients underwent cardiac catheterizations at baseline and median of 8 months follow-up. All patients had clinical, echocardiographic, and N-terminal pro b-type natriuretic peptide studies, including the EPPVDN pediatric pulmonary hypertension (PH) risk score. RESULTS: There was no death during the use of selexipag. Two of 15 patients ultimately underwent lung transplantation. One patient with heritable PAH died on intravenous treprostinil (off selexipag). The mean right atrial pressure, the ratio of pulmonary arterial pressure (PAP) to systemic arterial pressure (SAP) (mean PAP/mean SAP, diastolic PAP/diastolic SAP: -17%), and transpulmonary pressure gradients (TPG) (mean TPG: -17%; p < 0.01; diastolic TPG: -6 mm Hg; p < 0.05) were improved after the therapy (n = 10). Selexipag therapy was associated with a better right ventricular systolic function (tricuspid annular plane systolic excursion: +14.5%; p < 0.01) and functional class. Improvement was seen in non-invasive and combined invasive/non-invasive PH risk scores (lower risk: +18%-22%, higher risk: -35%-37%; p < 0.05). Overall, the efficacy of selexipag was variable, often with a better response in less sick patients. CONCLUSIONS: Oral selexipag use in children with PAH is well tolerated and safe when closely monitored. Add-on selexipag therapy improved several outcome-relevant variables in about 50% of patients and prevented disease progression in additional 27% of patients. The novel EPPVDN pediatric PH risk score indicated these drug effects properly, can be useful in clinical follow-up, and should be validated in larger prospective studies.

Update on noninvasive imaging of right ventricle dysfunction in pulmonary hypertension.

Pulmonary hypertension (PH) is a progressive disease affecting patients across the life span. The pathophysiology primarily involves the pulmonary vasculature and right ventricle (RV), but eventually affects the left ventricular (LV) function as well. Safe, accurate imaging modalities are critical for diagnosis, serial monitoring, and tailored therapy. While cardiac catheterization remains the conventional modality for establishing diagnosis and serial monitoring, noninvasive imaging has gained considerable momentum in providing accurate assessment of the entire RV-pulmonary axis. In this state-of-the-art review, we will discuss the most recent developments in echocardiography, magnetic resonance imaging, and computed tomography in PH evaluation from pediatric to adult population.

Challenges and Special Aspects of Pulmonary Hypertension in Middle- to Low-Income Regions: JACC State-of-the-Art Review.

Challenges and special aspects related to the management and prognosis of pulmonary hypertension (PH) in middle- to low-income regions (MLIRs) range from late presentation to comorbidities, lack of resources and expertise, cost, and rare options of lung transplantation. Expert consensus recommendations addressing the specific challenges for prevention and therapy of PH in MLIRs with limited resources have been lacking. To date, 6 MLIR-PH registries containing mostly adult patients with PH exist. Importantly, the global prevalence of PH is much higher in MLIRs compared with high-income regions: group 2 PH (left heart disease), pulmonary arterial hypertension associated with unrepaired congenital heart disease, human immunodeficiency virus, or schistosomiasis are highly prevalent. This consensus statement provides selective, tailored modifications to the current PH guidelines to address the specific challenges faced in MLIRs, resulting in the first pragmatic and cost-effective consensus recommendations for PH care providers, patients, and their families.