BackgroundThe 12-week, phase III Pulmonary Arterial hyperTENsion sGC-stimulator Trial (PATENT)-1 study investigated riociguat in patients with pulmonary arterial hypertension (PAH). Here, we present a prospectively planned analysis of the safety and efficacy of riociguat in the subgroup of patients with PAH associated with connective tissue disease (PAH-CTD).MethodsPatients with PAH-CTD were further classified post hoc as having PAH associated with systemic sclerosis or PAH-other defined CTD. In PATENT-1, patients received riociguat (maximum 2.5 or 1.5 mg three times daily) or placebo. Efficacy endpoints included change from baseline in 6-minute walking distance (6MWD; primary endpoint), haemodynamics and WHO functional class (WHO FC). In the long-term extension PATENT-2, patients received riociguat (maximum 2.5 mg three times daily); the primary endpoint was safety and tolerability.ResultsIn patients with PAH-CTD, riociguat increased mean 6MWD, WHO FC, pulmonary vascular resistance and cardiac index. Improvements in 6MWD and WHO FC persisted at 2 years. Two-year survival of patients with PAH-CTD was the same as for idiopathic PAH (93%). Riociguat had a similar safety profile in patients with PAH-CTD to that of the overall population.ConclusionsRiociguat was well tolerated and associated with positive trends in 6MWD and other endpoints that were sustained at 2 years in patients with PAH-CTD.Trial registration numbersPATENT-1 (NCT00810693), PATENT-2 (NCT00863681).

Statins have been shown to both prevent and attenuate pulmonary hypertension in animal models. This study investigates the potential therapeutic benefits of atorvastatin as an affordable treatment for pulmonary hypertension patients. 220 patients with pulmonary arterial hypertension (PAH) or chronic thromboembolic pulmonary hypertension (CTEPH) were randomised, double-blind, to receive atrovastatin 10 mg daily or matching placebo in addition to supportive care.At 6 months, 6-min walk distance decreased by 16.6 m in the atorvastatin group and 14.1 m in the placebo group. The mean placebo-corrected treatment effect was -2.5 m (95% CI: -38-33; p50.96), based on intention to treat. A small nonsignificant increase in pulmonary vascular resistance and fall in cardiac output was seen in both treatment groups. There was no significant difference in the proportion of patients who improved, remained stable or showed a deterioration in World Health Organization functional class between atorvastatin and placebo treatments. Nine patients died in the atorvastatin group and 11 in the placebo group. Serum cholesterol levels fell significantly on atorvastatin treatment. Discontinuation rates were 23.2% and 26.9% on atorvastatin and placebo, respectively.Atorvastatin 10 mg daily has no beneficial effect on the natural history of PAH or CTEPH over 6 months.

Supplemental Digital Content is available in the text.

P ulmonary arterial hypertension (PAH) is a disease of progressive vascular remodeling characterized by dysregulated growth of pulmonary vascular cells and inflammation. [1][2][3][4] In the search for new medicines, the focus is moving toward therapies targeting these mechanisms, drawing on approved oncology interventions, such as tyrosine kinase inhibitors (eg, imatinib) 5,6 and metabolic modulators (eg, dichloroacetate), 7,8 and antiinflammatory treatments. 9 The evaluation of these antiremodeling and anti-inflammatory strategies in PAH patients poses a considerable challenge that may hamper their development. Background-Pulmonary arterial hypertension (PAH) is a disease of progressive vascular remodeling, characterizedby dysregulated growth of pulmonary vascular cells and inflammation. A prevailing view is that abnormal cellular metabolism, notably aerobic glycolysis that increases glucose demand, underlies the pathogenesis of PAH. Increased lung glucose uptake has been reported in animal models. Few data exist from patients with PAH. Methods and Results-Dynamic positron emission tomography imaging with fluorine-18-labeled 2-fluoro-2-deoxyglucose ( Clinical Perspective on p 1224Noninvasive molecular imaging with the use of positron emission tomography (PET) offers enormous potential for monitoring cellular and biochemical events in otherwise inaccessible tissue and has been used in oncology to assess antiproliferative therapeutics. Specifically, fluorine-18-labeled 2-fluoro-2-deoxyglucose ( 18 FDG), a glucose analogue, is widely used for the detection and staging of a variety of malignant lesions and can provide a quantitative assessment of response to treatment.10-13 18 FDG PET exploits the "Warburg effect," 14,15 the observation that many cancers use aerobic cytoplasmic glycolysis as opposed to mitochondrial glucose oxidation as a major energy source, a process that requires increased cellular glucose uptake.Aerobic glycolysis is also a characteristic of nonmalignant proliferating cells and is observed in human pulmonary endothelial cells isolated and cultured from idiopathic PAH (IPAH) patient lungs, 16 as well as in pulmonary arterial smooth muscle cells from rodent PAH models.17 Lung parenchymal glucose uptake, measured by 18 FDG PET, has been reported to be increased in IPAH patients compared with healthy controls. 16,18 Recently, Marsboom et al 19 showed an increased lung 18 FDG PET signal in animal PAH models that is reduced by treatment with imatinib and dichloroacetate. These data provide the foundation for further investigation of the utility of 18 FDG PET as a tool in the assessment of patients with PAH. We set out to explore 3 questions: (1) the utility of dynamic 18 FDG PET acquisition in discriminating between PAH patients and healthy controls; (2) the feasibility of 18 FDG PET in tracking the pathology of pulmonary hypertension in in vivo PAH models and their response to treatment; and (3) the impact of treatments on cellular 18 FDG uptake with the use of IPAH-derived cells in vitro. Our da...

No abstract

Background: Soluble suppression of tumorigenicity (sST2) has been proposed to be a marker for biomechanical strain and a possible predictor of mortality in patients with chronic heart failure. The use of sST2 in pulmonary arterial hypertension (PAH) has not been well defined. Hypothesis: Plasma sST2 levels may correlate with the disease severity and predict clinical worsening in PAH. Methods: We performed a cohort study of 40 idiopathic PAH patients with data on demographics, exercise capacity, echocardiographic parameters, laboratory tests, hemodynamics, and medications. Plasma sST2 was assessed with the high-sensitivity ST2 ELISA kit at diagnostic catheterization. All patients were followed up from the date of blood sampling. The endpoint was clinical worsening. Results: sST2 was significantly elevated in patients with idiopathic PAH compared with control subjects (28.9 ± 13.9 vs 20.7 ± 7.5 ng/mL, P = 0.003). Pearson correlation analysis revealed that sST2 levels correlated with cardiac index (r = −0.534, P = 0.000) and pulmonary vascular resistance (r = 0.350, P = 0.027), and could reflect disease severity of PAH. After a mean follow-up of 14 ± 5 months, 12 patients showed clinical worsening. Receiver operating characteristic analysis suggested that sST2 levels >31.4 ng/mL discriminated clinical worsening with a sensitivity and specificity of 83.3% and 78.6%, respectively. Kaplan-Meier analysis showed that higher sST2 levels (>31.4 ng/mL) were associated with poor clinical outcomes (P = 0.008). Multivariate Cox regression analysis showed that sST2 was an independent predictor of clinical worsening (hazard ratio: 6.067, 95% confidence interval: 1.317-27.948, P = 0.021). Conclusions: sST2 correlates with disease severity and is a significant predictor of clinical worsening in patients with PAH.

C-reactive protein (CRP) is well-known inflammatory marker, and recognized as a risk predictor of pulmonary arterial diseases. Although statins have a beneficial effect in animal models and patients with pulmonary arterial hypertension (PAH), the underlying mechanisms of their actions have less been investigated. The aims of this study was to examined the effects of CRP on expressions of interleukin-6 (IL-6) and monocyte chemoattractant protein-1 (MCP-1), and the possible mechanisms of atorvastatin on CRP-induced IL-6 and MCP-1 production in cultured human pulmonary artery smooth muscle cells (PASMCs). In a preliminary study, the human PASMCs were stimulated by a variety of concentrations of CRP (5-200 μg/mL) at different time points (0, 3, 6, 9, 12, 18 and 24 h) for the purpose of determining the dose-and timedependent effects of CRP on inflammatory response of the cells. Then, the cells were pre-incubated for 2 h with atorvastatin (0.1-10 μmol/L) in the presence of CRP. The supernatant levels of both IL-6 and MCP-1 secretion were examined by ELISA. The cellular mRNA expressions of IL-6 and MCP-1 and nuclear factor-κB (NF-κB) activity were determined by real-time reverse transcription and polymerase chain reaction (RT-PCR) and electrophoretic mobility shift assay (EMSA), respectively. CRP resulted in elevated IL-6 and MCP-1 secretion and mRNA expression in a dose-and time-dependent manner. In addition, CRP also significantly activated the NF-κB pathway. Preincubation with 0.1-10 μmol/L of atorvastatin significantly decreased the secretions of IL-6 and MCP-1 induced by CRP. Moreover, 10 μmol/L of atorvastatin completely abrogated CRP-induced increase in IL-6 and MCP-1 by attenuating the activation of NF-κB. The present study demonstrated that inhibiting effect of atorvastatin on CRP-induced inflammatory response in cultured PASMCs was associated with NF-κB pathway. This pathway might represent a promising target for controlling CRP-induced inflammatory response in pulmonary arterial diseases.

This study measured glucose uptake in the right ventricle (RV) of patients with pulmonary hypertension and investigated the relationship to hemodynamics and survival. Myocardial 18F-fluorodeoxy-glucose (FDG) uptake was measured using single-photon positron emission tomography (SPECT) in 24 patients with idiopathic pulmonary arterial hypertension (IPAH) and 43 patients with congenital heart disease (CHD). In both IPAH and CHD-PAH, RV FDG uptake (RV/LV ratio) was associated with pulmonary vascular resistance (PVR). A second SPECT scan was performed in nine patients after 6 months treatment with sildenafil. PVR decreased from 1683±426 to 1207±383 dyn s-1 cm-5 (P < 0.05) and cardiac index improved from 2.2±0.2 to 2.8±0.5 L/min/m2 (P < 0.01). RV/LV FDG uptake decreased from 1.28±0.32 before treatment to 0.99±0.23 (P < 0.05). Survival in the IPAH group with a baseline RV/LV FDG uptake greater than the median value of 1.20 was significantly lower than that of the group with RV/LV FDG uptake below 1.20 (log-rank test, P < 0.05). In contrast, baseline RV/LV FDG was of little informative value in CHD. FDG uptake by the RV reflects the severity of PVR in PAH. Increased RV FDG uptake is a marker of poor prognosis in IPAH and is reduced in patients receiving effective therapy. It could prove useful in the early clinical assessment of novel therapies for PAH.