De-escalation of Oxygen Therapy and Medication in Patients With Chronic Thromboembolic Pulmonary Hypertension After Balloon Pulmonary Angioplasty.

BACKGROUND: There is no consensus on the adjustment of home oxygen therapy (HOT) and pulmonary hypertension (PH)-specific medications after balloon pulmonary angioplasty (BPA) in patients with chronic thromboembolic pulmonary hypertension (CTEPH). We aimed to examine the status of de-escalation and discontinuation of HOT and PH-specific medications post-BPA and clarify its effect on hemodynamics, biomarkers, and long-term outcomes. METHODS: From November 2012 to May 2018, 135 consecutive patients with CTEPH who underwent BPA at a single university hospital were enrolled (age, 63.5 ± 13.5 years; World Health Organization functional class (WHO-FC) II, III, IV; 34, 92, 9). RESULTS: The mean pulmonary arterial pressure decreased from 37.7 ± 11.3 to 20.4 ± 5.1 mm Hg 1 year post-BPA (P < 0.01). The proportion of patients who required HOT and combination medical therapy (≥ 2 PH-specific medications) decreased 1 year post-BPA (from 58.5% to 7.4% and from 40.0% to 10.4%, respectively). Baseline factors influencing the requirement of HOT and combination medical therapy post-BPA were almost identical (ie, lower exercise capacity and pulmonary diffusion capacity and worse hemodynamics). Regardless of their discontinuation, the improved hemodynamics, functional capacity (WHO-FC), and biomarkers (B-type natriuretic peptide and high-sensitivity troponin T) were almost maintained, and no adverse 1-year clinical outcomes (all-cause death and PH-related hospitalization) were observed. CONCLUSIONS: Most patients with CTEPH discontinued HOT and PH-specific combination medical therapy post-BPA, which was not associated with the deterioration of hemodynamics, functional capacity, or biomarkers. No long-term adverse outcomes were observed.

The complement C3-complement factor D-C3a receptor signalling axis regulates cardiac remodelling in right ventricular failure.

Failure of the right ventricle plays a critical role in any type of heart failure. However, the mechanism remains unclear, and there is no specific therapy. Here, we show that the right ventricle predominantly expresses alternative complement pathway-related genes, including Cfd and C3aR1. Complement 3 (C3)-knockout attenuates right ventricular dysfunction and fibrosis in a mouse model of right ventricular failure. C3a is produced from C3 by the C3 convertase complex, which includes the essential component complement factor D (Cfd). Cfd-knockout mice also show attenuation of right ventricular failure. Moreover, the plasma concentration of CFD correlates with the severity of right ventricular failure in patients with chronic right ventricular failure. A C3a receptor (C3aR) antagonist dramatically improves right ventricular dysfunction in mice. In summary, we demonstrate the crucial role of the C3-Cfd-C3aR axis in right ventricular failure and highlight potential therapeutic targets for right ventricular failure.

TET2 Variants in Japanese Patients With Pulmonary Arterial Hypertension.

Recent studies have illuminated the importance of tet-methylcytosine-dioxygenase-2 (TET2) in pulmonary arterial hypertension (PAH). We aimed to clarify the frequency of TET2 variants in Japanese PAH patients. Among whole-exome sequencing of 145 Japanese patients with idiopathic or heritable PAH, 3 patients (2.1%) had a germline heterozygous missense variant in TET2 (c.3116C > T, p.Ser1039Leu). The allele frequency is 0.15% in the gnomAD database, and 0.2% among 3554 in the general Japanese population. These 3 patients needed combination therapy including continuous prostacyclin infusion. Our study identified a novel TET2 variant, and TET2 may have effects on the onset and/or disease progression of PAH.

Des études récentes ont mis en lumière l'importance de TET méthylcytosine dioxygénase 2 (TET2) dans l'hypertension artérielle pulmonaire (HTAP). Nous avons cherché à préciser la fréquence des mutations du gène TET2 chez des patients japonais atteints d'HTAP. Lors du séquençage de l'exome entier de 145 patients japonais présentant une HTAP idiopathique ou héréditaire, une mutation germinale hétérozygote faux-sens du TET2 (c.3116C > T, p.Ser1039Leu) a été détectée chez trois patients (2,1 %). La fréquence allélique est de 0,15 % dans la base de données gnomAD et de 0,2 % parmi 3 554 personnes au sein de la population japonaise en général. Les trois patients ont dû suivre un traitement d'association faisant notamment appel à la prostacycline administrée en perfusion continue. Notre étude a permis de découvrir une nouvelle mutation du gène TET2, et le TET2 peut avoir des effets sur l'apparition et/ou la progression de l'HTAP.

RNF213-Associated Vascular Disease: A Concept Unifying Various Vasculopathies.

The ring finger protein 213 gene (RNF213) encodes a 590 kDa protein that is thought to be involved in angiogenesis. This gene was first recognized as a vasculopathy-susceptibility locus through genome-wide association studies undertaken in a Japanese population, demonstrating that heterozygotes for RNF213 p.Arg4810Lys (c.14429G>A, rs112735431) had a greatly increased risk of moyamoya disease. The association of RNF213 p.Arg4810Lys as a susceptibility variant of moyamoya disease was reproduced in Korean and Chinese individuals and, later, in Caucasians. Variants of the RNF213 gene have been linked to a number of vascular diseases such as moyamoya disease, intracranial major artery stenosis, pulmonary arterial hypertension, and peripheral pulmonary artery stenosis, and have also been associated with co-occurrent diseases and vascular disease in different organs. Based on the findings that we have reported to date, our paper proposes a new concept of "RNF213-associated vascular disease" to unify these conditions with the aim of capturing patients with multiple diseases but with a common genetic background. This concept will be highly desirable for clarifying all of the diseases in the RNF213-associated vascular disease category by means of global epidemiological investigations because of the possibility of such diseases appearing asymptomatically in some patients.

Qualitative and Quantitative Effects of Fatty Acids Involved in Heart Diseases.

Fatty acids (FAs) have structural and functional diversity. FAs in the heart are closely associated with cardiac function, and their qualitative or quantitative abnormalities lead to the onset and progression of cardiac disease. FAs are important as an energy substrate for the heart, but when in excess, they exhibit cardio-lipotoxicity that causes cardiac dysfunction or heart failure with preserved ejection fraction. FAs also play a role as part of phospholipids that compose cell membranes, and the changes in mitochondrial phospholipid cardiolipin and the FA composition of plasma membrane phospholipids affect cardiomyocyte survival. In addition, FA metabolites exert a wide variety of bioactivities in the heart as lipid mediators. Recent advances in measurement using mass spectrometry have identified trace amounts of n-3 polyunsaturated fatty acids (PUFAs)-derived bioactive metabolites associated with heart disease. n-3 PUFAs have a variety of cardioprotective effects and have been shown in clinical trials to be effective in cardiovascular diseases, including heart failure. This review outlines the contributions of FAs to cardiac function and pathogenesis of heart diseases from the perspective of three major roles and proposes therapeutic applications and new medical perspectives of FAs represented by n-3 PUFAs.

Impact of additional selexipag on prostacyclin infusion analogs in patients with pulmonary arterial hypertension.

The effective therapy for pulmonary arterial hypertension (PAH) with inadequate clinical response is scarce except for lung transplantation when prostacyclin infusion is ineffective. The purpose of this study is to investigate the efficacy and safety of selexipag in addition to the infusion of prostacyclin. Nine patients [median 38 (36-49) years of age; 78% female] with PAH whose clinical response was inadequate despite the use of prostacyclin infusion analogs, were evaluated. Addition of selexipag significantly improved hemodynamics and no serious adverse events were observed. Selexipag with prostacyclin infusion analogs can be an effective therapeutic strategy for the PAH patients with inadequate clinical response.

Pharmacokinetics of hydrogen after ingesting a hydrogen-rich solution: A study in pigs.

Drinking hydrogen (H2)-rich water is a common way to consume H2. Although many studies have shown efficacy of drinking H2-rich water in neuropsychiatric and endocrine metabolic disorders, their authenticity has been questioned because none examined the associated pharmacokinetics of H2. Therefore, we performed the first study to investigate the pharmacokinetics of H2 in pigs given an H2-rich glucose solution with the aim to extrapolate the findings to humans. We inserted blood collection catheters into the jejunal and portal veins, suprahepatic inferior vena cava, and carotid artery of 4 female pigs aged 8 weeks. Then, within 2 min we infused 500 ml of either H2-rich or H2-free glucose solution into the jejunum via a percutaneous gastrostomy tube and measured changes in H2 concentration in venous and arterial blood over 120 min. After infusion of the H2-rich glucose solution, H2 concentration in the portal vein peaked at 0.05 mg/L and remained at more than 0.016 mg/L (H2 saturation level, 1%) after 1 h; it also increased after infusion of H2-free glucose solution but remained below 0.001 mg/L (H2 saturation level, 0.06%). We assume that H2 was subsequently metabolized in the liver or eliminated via the lungs because it was not detected in the carotid artery. In conclusion, drinking highly concentrated H2-rich solution within a short time is a good way to increase H2 concentration in portal blood and supply H2 to the liver.

Triple oral combination therapy with macitentan, riociguat, and selexipag for pulmonary arterial hypertension.

BACKGROUND: The evidence regarding triple oral combination therapy for patients with pulmonary arterial hypertension (PAH) is scarce. This study was performed to investigate the effectiveness and safety of triple oral combination therapy with macitentan, riociguat, and selexipag. METHODS: Among consecutive patients with PAH who were referred to our hospital from 2009 to 2020, those who underwent triple oral combination therapy using macitentan, riociguat, and selexipag were retrospectively analyzed. Hemodynamic and echocardiographic assessments and Kaplan-Meier analyses of all-cause death and initiation of prostacyclin infusion were conducted. RESULTS: Twenty-six patients underwent this combination therapy. These patients were predominantly female (73.1%) with a median age of 38 years at baseline and nine patients were taking some PAH medications at baseline. The median time from initiation of the first PAH drug to the third PAH drug in treatment naïve patients was 24 days (interquartile range, 12-47 days). Four patients (15.0%) discontinued taking any of the three vasodilators because of adverse events, and 17 patients (65.4%) reached the maximum dose of all three drugs. The mean pulmonary arterial pressure, pulmonary vascular resistance, and cardiac output improved by 29%, 65%, and 82%, respectively (median observation period: 441 days) and similar improvements were observed in treatment-naïve patients at baseline. The survival rate and prostacyclin infusion-free rate since administration of all three vasodilators was 93.3% and 74.6% at 3 years, respectively. When patients were divided by risk stratification, the prostacyclin-free rate at 3 years was 92.9% in low-/intermediate-risk patients and 55.0% in high-risk patients. CONCLUSION: Triple oral combination therapy with macitentan, riociguat, and selexipag sufficiently improved clinical parameters and was well tolerated in patients with PAH. This combination could be a particularly promising strategy in patients with low/intermediate risk and possibly even in half of patients with high risk. Further studies are needed to validate these findings.The reviews of this paper are available via the supplemental material section.

TNFRSF13B c.226G>A (p.Gly76Ser) as a Novel Causative Mutation for Pulmonary Arterial Hypertension.

Background Recently, some studies reported the pulmonary artery hypertension (PAH)-associated genes. However, a majority of patients with familial or sporadic PAH lack variants in the known pathogenic genes. In this study, we investigated the new causative gene variants associated with PAH. Methods and Results Whole-exome sequencing in 242 Japanese patients with familial or sporadic PAH identified a heterozygous substitution change involving c.226G>A (p.Gly76Ser) in tumor necrotic factor receptor superfamily 13B gene (TNFRSF13B) in 6 (2.5%) patients. TNFRSF13B controls the differentiation of B cell and secretion of inflammatory cytokines and may be involved in vascular inflammation. In silico structural analysis simulation demonstrated the structural instability of the N-terminal region of the protein synthesized from TNFRSF13B p.Gly76Ser variant. These suggest that the TNFRSF13B p.Gly76Ser variant may be involved in the development of PAH via aberrant inflammation in pulmonary vessels. Conclusions TNFRSF13B p.Gly76Ser variant is a candidate of novel causative gene variant for PAH.