[Targeted therapy for pulmonary arterial hypertension in patients without comorbidities]. / Gezielte medikamentöse Therapie der pulmonalarteriellen Hypertonie bei Patient*innen ohne Komorbiditäten.

The 2022 guidelines on pulmonary hypertension from the European Society of Cardiology (ESC) and the European Respiratory Society (ERS) provide therapeutic strategies that account for the variability in the clinical presentation of newly diagnosed patients. We summarize treatment recommendations for pulmonary arterial hypertension (PAH) in patients without significant comorbidities, particularly for idiopathic, hereditary, drug/toxin-induced, or connective tissue disease-associated PAH. In this group of patients, multidimensional assessments for short-term mortality risk guide initial treatment decisions and treatment decisions during follow-up. Upfront dual combination therapy (phosphodiesterase type-5 inhibitor and endothelin receptor antagonist) is recommended for low- and intermediate-risk patients, and triple therapy including a parenteral prostacyclin should be considered in high- or intermediate-high-risk patients. If a low or intermediate-low-risk profile cannot be achieved during therapy, sequential add-on therapy escalation with parenteral prostacyclin or a prostacyclin receptor agonist should be considered, and switching from a phosphodiesterase type-5 inhibitor to a guanylate cyclase stimulator may also be considered.

[General measures and management of pulmonary arterial hypertension]. / Allgemeine Maßnahmen und Management der pulmonalarteriellen Hypertonie.

Care of patients with pulmonary arterial hypertension (PAH) needs a multi-facetet concept and measures, including management of adverse reactions, right heart insufficiency as well as information on pregnancy, travels by air, psychosocial support, physical exercise training and prophylaxis by vaccination.Positive study results led to an higher recommendation of specialized exercise training in pulmonary hypertension. Also, the recommendation on iron substitution was amended according to the current evidence.In the current guidelines, special focus was given to the elaboration of recommendations regarding pregnancy, including patient information, contraception and patient management in case of pregnancy.This article aims to provide an overview on the recommendations of general measuremes, special circumstances and patient management according to the ESC/ERS guidelines. Amendments to the guideline recommendations are given as comments from the authors of this article.

Long-Term Safety, Outcome, and Clinical Effects of Subcutaneous and Intravenous Treprostinil Treatment in Patients with Severe Chronic Pulmonary Arterial Hypertension.

BACKGROUND: Current guidelines recommend treatment with parenteral prostacyclin analogs in patients with severe pulmonary arterial hypertension (PAH), who have insufficient response to treatment. Real-life data are sought to help physicians in treatment decisions and clinical care of patients. OBJECTIVE: This study analyzed safety, clinical effects, and long-term outcomes of subcutaneous (sc) and/or intravenous (iv) treprostinil via different pump systems in consecutive patients with PAH. METHODS: Thirty-seven patients with severe progressive PAH despite dual combination therapy (20 female, mean age: 52.3 ± 15 years, mean pulmonary vascular resistance: 12.1 ± 5.1 WU) were initiated with add-on treprostinil sc and were routinely clinically assessed. Changes in clinical parameters, adverse events, and outcome were analyzed retrospectively. RESULTS: In 24 of 37 patients, treprostinil administration was continued iv via implantation of LENUS Pro® pump after 3 ± 1.3 months, 6 patients continued with sc therapy, and 7 discontinued treatment. After 3, 6, 9, and 12 months of treprostinil treatment, patients showed a significant improvement in mean 6-min walk distance and tricuspid annular plane systolic excursion compared to baseline. In 8 of the 24 patients, iv pumps required surgical revision. During a mean follow-up of 2.82 ± 1.95 years, 12 patients died, four received lung transplantation. Transplant-free survival after 1, 2, and 3 years was 85.7%, 69.2%, and 65.3%, respectively. CONCLUSION: sc treprostinil as add-on to double combination treatment significantly improved exercise capacity and right heart function. In most patients, treprostinil could be continued via more tolerable iv administration approach (LENUS Pro® pump), showing reasonable overall survival with respect to the severity of PAH.

Is iron deficiency caused by BMPR2 mutations or dysfunction in pulmonary arterial hypertension patients?

Iron deficiency is common in idiopathic and heritable pulmonary arterial hypertension patients (I/HPAH). A previous report suggested a dysregulation of the iron hormone hepcidin, which is controlled by BMP/SMAD signaling involving the bone morphogenetic protein receptor 2 (BMPR-II). Pathogenic variants in the BMPR2 gene are the most common cause of HPAH. Their effect on patients' hepcidin levels has not been investigated. The aim of this study was to assess whether iron metabolism and regulation of the iron regulatory hormone hepcidin was disturbed in I/HPAH patients with and without a pathogenic variant in the gene BMPR2 compared to healthy controls. In this explorative, cross-sectional study hepcidin serum levels were quantified by enzyme-linked immunosorbent assay. We measured iron status, inflammatory parameters and hepcidin modifying proteins such as IL6, erythropoietin, and BMP2, BMP6 in addition to BMPR-II protein and mRNA levels. Clinical routine parameters were correlated with hepcidin levels. In total 109 I/HPAH patients and controls, separated into three groups, 23 BMPR2 variant-carriers, 56 BMPR2 noncarriers and 30 healthy controls were enrolled. Of these, 84% had iron deficiency requiring iron supplementation. Hepcidin levels were not different between groups and corresponded to the degree of iron deficiency. The levels of IL6, erythropoietin, BMP2, or BMP6 showed no correlation with hepcidin expression. Hence, iron homeostasis and hepcidin regulation was largely independent from these parameters. I/HPAH patients had a physiologically normal iron regulation and no false elevation of hepcidin levels. Iron deficiency was prevalent albeit independent of pathogenic variants in the BMPR2 gene.

Hypochromic red cells as a prognostic indicator of survival among patients with systemic sclerosis screened for pulmonary hypertension.

BACKGROUND: Patients with systemic sclerosis (SSc) are frequently affected by iron deficiency, particularly those with pulmonary hypertension (PH). The first data indicate the prognostic importance of hypochromic red cells (% HRC) > 2% among patients with PH. Hence, the objective of our study was to investigate the prognostic value of % HRC in SSc patients screened for PH. METHODS: In this retrospective, single-center cohort study, SSc patients with a screening for PH were enrolled. Clinical characteristics and laboratory and pulmonary functional parameters associated with the prognosis of SSc were analyzed using uni- and multivariable analysis. RESULTS: From 280 SSc patients screened, 171 could be included in the analysis having available data of iron metabolism (81% female, 60 ± 13 years of age, 77% limited cutaneous SSc, 65 manifest PH, and 73 pulmonary fibrosis). The patients were followed for 2.4 ± 1.8 (median 2.4) years. HRC > 2% at baseline was significantly associated with worse survival in the uni- (p = 0.018) and multivariable (p = 0.031) analysis independent from the presence of PH or pulmonary parenchymal manifestations. The combination of HRC > 2% and low diffusion capacity for carbon monoxide (DLCO) ≤ 65% predicted was significantly associated with survival (p < 0.0001). CONCLUSION: This is the first study reporting that HRC > 2% is an independent prognostic predictor of mortality and can possibly be used as a biomarker among SSc patients. The combination of HRC > 2% and DLCO ≤ 65% predicted could serve in the risk stratification of SSc patients. Larger studies are required to confirm these findings.

Oxygenated hemoglobin as prognostic marker among patients with systemic sclerosis screened for pulmonary hypertension.

Oxygenated hemoglobin (OxyHem) in arterial blood may reflect disease severity in patients with systemic sclerosis (SSc). The aim of this study was to analyze the predictive value of OxyHem in SSc patients screened for pulmonary hypertension (PH). OxyHem (g/dl) was measured by multiplying the concentration of hemoglobin with fractional oxygen saturation in arterialized capillary blood. Prognostic power was compared with known prognostic parameters in SSc using uni- and multivariable analysis. A total of 280 SSc patients were screened, 267 were included in the analysis. No signs of pulmonary vascular disease were found in 126 patients, while 141 patients presented with mean pulmonary arterial pressure ≥ 21 mmHg. Interstitial lung disease (ILD) was identified in 70 patients. Low OxyHem ≤ 12.5 g/dl at baseline was significantly associated with worse survival (P = 0.046). In the multivariable analysis presence of ILD, age ≥ 60 years and diffusion capacity for carbon monoxide (DLCO) ≤ 65% were negatively associated with survival. The combination of low DLCO and low OxyHem at baseline could predict PH at baseline (sensitivity 76.1%). This study detected for the first time OxyHem ≤ 12.5 g/dl as a prognostic predictor in SSc patients. Further studies are needed to confirm these results.

Tolerability, safety and survival in patients with severe pulmonary arterial hypertension treated with intravenous epoprostenol (Veletri®): a prospective, 6-months, open label, observational, non-interventional study.

BACKGROUND: Epoprostenol AS (Veletri®), a thermostable epoprostenol formulation, provides better drug stability and improved clinical use compared to previous epoprostenol formulations. This study aims to expand clinical experience in the use of Veletri®, especially regarding tolerability, safety and survival. METHODS: Pulmonary arterial hypertension (PAH) patients at high risk despite pretreatment with at least double oral combination therapy and with clinical indication for epoprostenol (Veletri®) treatment were consecutively included in this prospective, open label, observational, non-interventional study. Clinical data were assessed at baseline, after 3 and 6 months. Adverse events (AEs) and serious adverse events (SAEs) were documented. Survival from initiation of Veletri® was assessed at last patient out. RESULTS: Fifteen patients (60 ± 13.7 years, WHO functional class III (n = 10) or IV (n = 5), severely impaired right ventricular function, mean pulmonary arterial pressure 54.8 ± 8.9 mmHg, mean pulmonary vascular resistance 4.4 ± 0.7 (median 3.8) Wood Units) were enrolled and treated with a mean dosage of 7.9 ± 3.9 (median 7.5) ng/kg/min. Eleven patients completed the study (treatment withdrawal n = 1, death n = 3). After a mean follow-up of 19.1 ± 13.5 (median 18.0) months, seven patients died and three were listed for lung transplantation. Seven AEs (nausea n = 3, diarrhea n = 1, flushing n = 2, headaches n = 1) and three SAEs (catheter infection n = 2, catheter occlusion n = 1) were related to Veletri®. The 1- and 2-year survival rates were 73.3% and 52.4%, respectively. CONCLUSIONS: The study showed that safety and tolerability of epoprostenol AS (Veletri®) was comparable to previous prostacyclin formulations and was feasible for most patients. The maximum tolerable dosage was lower than dosages reported in the literature. In future applications/trials the up-titration process should be pushing for higher dosages of epoprostenol in the occurrence of side effects, as the achievement of a high and effective dosage is crucial for the clinical benefit of the patients. Survival was as expected in these prevalent severely impaired patients. Trial registration The study was registered in the EUPAS registry (EUPAS32492).

Impairment of Inspiratory Muscle Function after COVID-19.

BACKGROUND: Persistent symptoms after acute coronavirus-disease-2019 (COVID-19) are common, and there is no significant correlation with the severity of the acute disease. In long-COVID (persistent symptoms >4 weeks after acute COVID-19), respiratory symptoms are frequent, but lung function testing shows only mild changes that do not explain the symptoms. Although COVID-19 may lead to an impairment of the peripheral nervous system and skeletal muscles, respiratory muscle function has not been examined in this setting. METHODS: In this study, we assessed the severity of dyspnea (NYHA-function class) in long-COVID patients and analyzed its association with body mass index (BMI), FEV1, forced vital capacity, other parameters of body plethysmography, diffusing capacity for carbon monoxide (DLCO), arterial blood gases, and inspiratory muscle function, assessed by airway occlusion pressure (P0.1) and maximal inspiratory pressure (PImax) in two respiratory clinics in Germany between Oct 2020 and Aug 2021. RESULTS: A total of 116 patients were included in the study. The mean age was 50.2 ± 14.5 years; BMI, 26.7 ± 5.87 kg/m2; NYHA class I, 19%; II, 27%; III, 41%; and IV, 14%. While lung function values and computed tomography or conventional X-ray of the chest were in the normal range, inspiratory muscle function was markedly impaired. P01 was elevated to 154 ± 83%predicted and PImax was reduced to 41 ± 25%predicted. PImax reduction was strongly associated with the severity of dyspnea but independent of BMI, time after acute COVID-19 and most of the other parameters. CONCLUSIONS: This study shows that in long-COVID patients, respiratory symptoms may be mainly caused by reduced inspiratory muscle strength. Assessment of PImax and P0.1 might better explain dyspnea than classical lung function tests and DLCO. A prospective study is needed to confirm these results.

Prognostic meaning of right ventricular function and output reserve in patients with systemic sclerosis.

BACKGROUND: The objective of this study was to investigate the prognostic impact of right ventricular (RV) function at rest and during exercise in patients with systemic sclerosis (SSc) presenting for a screening for pulmonary hypertension (PH). METHODS: In this study, data from SSc patients who underwent routinely performed examinations for PH screening including echocardiography and right heart catheterization at rest and during exercise were analysed. Uni- and multivariable analyses were performed to identify prognostic parameters. RESULTS: Out of 280 SSc patients screened for PH, 225 were included in the analysis (81.3% female, mean age 58.1±13.0 years, 68% limited cutaneous SSc, WHO-FC II-III 74%, 24 manifest PH). During the observation period of 3.2±2.7 (median 2.6) years 35 patients died. Tricuspid annular plane systolic excursion (TAPSE) at rest <18 mm (p=0.001), RV output reserve as increase of cardiac index (CI) during exercise <2 l/min (p<0.0001), RV pulmonary vascular reserve (Δ mean pulmonary artery pressure/Δ cardiac output) ≥3 mmHg/l/min (p<0.0001), peak CI <5.5 l/min/m2 (p=0.001), pulmonary arterial compliance <2 ml/mmHg (p=0.002), TAPSE/systolic pulmonary arterial pressure (sPAP) ratio ≤0.6 ml/mmHg (p<0.0001) and echocardiographic qualitative RV function at rest (p<0.0001) significantly predicted worse survival. In the multivariable analysis TAPSE/sPAP ratio and diffusion capacity for carbon monoxide ≤65% were identified as independent prognostic predictors and had 75% sensitivity and 69% specificity to predict future development of pulmonary vascular disease (PVD) during follow-up. CONCLUSIONS: This study demonstrates that assessment of RV function at rest and during exercise may provide crucial information to identify SSc patients who are at a high risk of poor outcome and for the development of PH and/or PVD.

Gene panel diagnostics reveals new pathogenic variants in pulmonary arterial hypertension.

BACKGROUND: A genetic predisposition can lead to the rare disease pulmonary arterial hypertension (PAH). Most mutations have been identified in the gene BMPR2 in heritable PAH. However, as of today 15 further PAH genes have been described. The exact prevalence across these genes particularly in other PAH forms remains uncertain. We present the distribution of mutations across PAH genes identified at the largest German referral centre for genetic diagnostics in PAH over a course of > 3 years. METHODS: Our PAH-specific gene diagnostics panel was used to sequence 325 consecutive PAH patients from March 2017 to October 2020. For the first year the panel contained thirteen PAH genes: ACVRL1, BMPR1B, BMPR2, CAV1, EIF2AK4, ENG, GDF2, KCNA5, KCNK3, KLF2, SMAD4, SMAD9 and TBX4. These were extended by the three genes ATP13A3, AQP1 and SOX17 from March 2018 onwards following the genes' discovery. RESULTS: A total of 79 mutations were identified in 74 patients (23%). Of the variants 51 (65%) were located in the gene BMPR2 while the other 28 variants were found in ten further PAH genes. We identified disease-causing variants in the genes AQP1, KCNK3 and SOX17 in families with at least two PAH patients. Mutations were not only detected in patients with heritable and idiopathic but also with associated PAH. CONCLUSIONS: Genetic defects were identified in 23% of the patients in a total of 11 PAH genes. This illustrates the benefit of the specific gene panel containing all known PAH genes.

Effect of Supervised Training Therapy on Pulmonary Arterial Compliance and Stroke Volume in Severe Pulmonary Arterial Hypertension and Inoperable or Persistent Chronic Thromboembolic Pulmonary Hypertension.

BACKGROUND: Pulmonary arterial compliance (PAC) is a prognostic parameter in pulmonary arterial hypertension (PAH) reflecting the elasticity of the pulmonary vessels. OBJECTIVES: The objective of this post hoc analysis of a prospective randomized controlled trial (RCT) was to assess the effect of exercise training on PAC and stroke volume (SV) in patients with PAH and persistent/inoperable chronic thromboembolic pulmonary hypertension (CTEPH). METHOD: From the previous RCT, 43 out of 87 patients with severe PAH (n = 29) and CTEPH (n = 14) had complete haemodynamic examinations at baseline and after 15 weeks by right heart catheterization and were analysed (53% female, 79% World Health Organization functional class III/IV, 58% combination therapy, 42% on supplemental oxygen therapy, training group n = 24, and control group n = 19). Medication remained unchanged for all patients. RESULTS: Low-dose exercise training at 4-7 days/week significantly improved PAC (training group 0.33 ± 0.65 mL/mm Hg vs. control group -0.06 ± 1.10 mL/mm Hg; mean difference 0.39 mL/mm Hg, 95% confidence interval [CI] 0.15-0.94 mL/mm Hg; p = 0.004) and SV (training group 9.9 ± 13.4 mL/min vs. control group -4.2 ± 11.0 mL/min; mean difference 14.2 mL, 95% CI 6.5-21.8 mL; p < 0.001) in the training versus control group. Furthermore, exercise training significantly improved cardiac output and pulmonary vascular resistance at rest, peak oxygen consumption, and oxygen pulse. CONCLUSIONS: Our findings suggest that supervised exercise training may improve right ventricular function and PAC at the same time. Further prospective studies are needed to evaluate these findings.

Supervised Exercise Training in Patients with Chronic Thromboembolic Pulmonary Hypertension as Early Follow-Up Treatment after Pulmonary Endarterectomy: A Prospective Cohort Study.

BACKGROUND: Data on exercise training in chronic thromboembolic pulmonary hypertension (CTEPH) after pulmonary endarterectomy (PEA) as well as data on clinical and haemodynamic changes shortly after PEA are lacking. OBJECTIVE: The objective of this prospective study was to analyse the safety, feasibility, and the effectiveness of combined supervised inpatient rehabilitation in patients with CTEPH directly after PEA. METHODS: CTEPH patients started a 19-week rehabilitation program (3 weeks as inpatients and continued at home for another 16 weeks) with supervised exercise training as follow-up treatment shortly after PEA. Haemodynamics were assessed by right heart catheterisation before PEA and 22 weeks after PEA. Non-invasive assessments as transthoracic echocardiography and 6-min walking distance (6MWD) were performed before PEA and after 3 (that is, beginning of rehabilitation), 6, and 22 weeks following PEA. Adverse events were recorded throughout the study. RESULTS: Forty-five CTEPH patients were included (49% female, 57.6 ± 12.4 years old, 60% WHO functional class III). Rehabilitation was started 3.3 ± 0.9 weeks after PEA. Exercise training was well tolerated in all patients without severe side effects. Haemodynamics measured by right heart catheterisation significantly improved from pre-PEA to 22 weeks post-PEA in cardiac output (+1.2 ± 1.5 L/min, 33.4%, p = 0.001) and mean pulmonary arterial pressure (-19 ± 13 mm Hg, -39.6%, p < 0.0001). Right heart size measured by echocardiography, 6MWD, quality of life, and oxygen saturation significantly improved not only within the first 3 weeks after PEA but also during the following 19 weeks of exercise training. CONCLUSIONS: Supervised exercise training was feasible as early follow-up treatment after PEA. Further controlled studies are needed to discriminate the effects of PEA and early follow-up rehabilitation. TRIAL REGISTRATION: The study was registered at clinicaltrials.gov (NCT01393327) on July 13, 2011. The study start date was January 2010, and completion date was December 2013.

Risk stratification and prognostic factors in patients with pulmonary arterial hypertension and comorbidities a cross-sectional cohort study with survival follow-up.

BACKGROUND: The objective of this study was to analyze prognostic factors and risk stratification in patients with pulmonary arterial hypertension (PAH) and comorbidities. METHODS: Patients with invasively diagnosed PAH were included in the analysis. Comorbidities were clinically diagnosed as proposed in the 6th World Symposium of pulmonary hypertension. Uni- and multivariate analysis were employed for identification of factors predicting survival and time to first clinical worsening (TTCW). Risk stratification was based on parameters from ESC/ERS-guidelines 2015. RESULTS: In total 142 patients were enrolled in the study, 90 of them were diagnosed as PAH without and 52 with comorbidities. All patients received targeted PAH therapy and were followed for 3.3 ± 2.4 years. In PAH patients without comorbidities survival and TTCW were significantly associated with reduced 6-min walking distance (6MWD), elevated N-terminal pro brain natriuretic peptide (NT-proBNP), WHO-functional class (WHO-FC) and right atrial (RA) area. In the multivariate analysis, 6MWD was an independent predictor for survival (p = 0.002) and WHO-FC for TTCW (p = 0.001). In patients with PAH and comorbidities these parameters had no significant association with survival and TTCW. Average risk score was significantly associated with survival (p = 0.001) and TTCW (p = 0.013) in PAH but not in PAH with comorbidities (both p > 0.05; figure 1). CONCLUSION: Risk stratification based on ESC/ERS-guidelines could only be confirmed in patients without comorbidities, but not in patients with PAH and comorbidities. The data of this study suggest, that a different risk stratification needs to be applied to PAH patients with comorbidities. Further studies are needed to confirm these results. TRIAL REGISTRATION: Not applicable, retrospective registry.

Myeloproliferative Diseases as Possible Risk Factor for Development of Chronic Thromboembolic Pulmonary Hypertension-A Genetic Study.

Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare disease which is often caused by recurrent emboli. These are also frequently found in patients with myeloproliferative diseases. While myeloproliferative diseases can be caused by gene defects, the genetic predisposition to CTEPH is largely unexplored. Therefore, the objective of this study was to analyse these genes and further genes involved in pulmonary hypertension in CTEPH patients. A systematic screening was conducted for pathogenic variants using a gene panel based on next generation sequencing. CTEPH was diagnosed according to current guidelines. In this study, out of 40 CTEPH patients 4 (10%) carried pathogenic variants. One patient had a nonsense variant (c.2071A>T p.Lys691*) in the BMPR2 gene and three further patients carried the same pathogenic variant (missense variant, c.1849G>T p.Val617Phe) in the Janus kinase 2 (JAK2) gene. The latter led to a myeloproliferative disease in each patient. The prevalence of this JAK2 variant was significantly higher than expected (p < 0.0001). CTEPH patients may have a genetic predisposition more often than previously thought. The predisposition for myeloproliferative diseases could be an additional risk factor for CTEPH development. Thus, clinical screening for myeloproliferative diseases and genetic testing may be considered also for CTEPH patients.

Flow rate variance of a fully implantable pump for the delivery of intravenous treprostinil in pulmonary arterial hypertension.

Implantable infusion pumps might improve the convenience and safety of intravenous treprostinil for pulmonary arterial hypertension. The LENUS Pro® pump (approved in Europe) has a fixed flow rate. Based on 126 pumps and 2853 refills, we retrospectively analyzed the actual flow rate from 09/2010 to 09/2018. A relevant flow rate variance is evident after three years; therefore, flow rate monitoring and dose adjustment are mandatory.

Haemodynamic phenotypes and survival in patients with systemic sclerosis: the impact of the new definition of pulmonary arterial hypertension.

BACKGROUND: In this study, we investigated the impact of the new haemodynamic definition of pulmonary arterial hypertension (PAH) as proposed by the 6th PH World Symposium on phenotypes and survival in patients with systemic sclerosis (SSc). METHODS: In SSc patients who were prospectively and consecutively screened for PAH including right heart catheterisation in Heidelberg or Zurich, haemodynamic and clinical variables have been reassessed according to the new PAH definition. Patients have been followed for 3.7±3.7 (median 3.4) years; Kaplan-Meier survival analysis was performed. Patients with significant lung or left heart disease were excluded from comparative analyses. RESULTS: The final dataset included 284 SSc patients, 146 patients (49.2%) had mean pulmonary arterial pressure (mPAP) ≤20 mm Hg, 19.3% had mPAP 21-24 mm Hg and 29.4% had mPAP ≥25 mm Hg. In the group of mildly elevated mPAP, only four patients (1.4% of the whole SSc cohort) had pulmonary vascular resistance (PVR) values ≥3 Wood Units (WU) and could be reclassified as manifest SSc-APAH. Twenty-eight (9.8%) patients with mPAP of 21-24 mm Hg and PVR ≥2 WU already presented with early pulmonary vascular disease with decreased 6 min walking distance (6MWD) (p<0.001), TAPSE (p=0.004) and pulmonary arterial compliance (p<0.001). A PVR ≥2 WU was associated with reduced long-term survival (p=0.002). PVR and 6MWD were independent prognostic predictors in multivariate analysis. CONCLUSION: The data of this study show that a PVR threshold ≥3 WU is too high to enable an early diagnosis of PAH. A PVR threshold ≥2 WU was already associated with pulmonary vascular disease, significantly reduced survival and would be more appropriate in SSc patients with mild PAH.

Early treatment with ambrisentan of mildly elevated mean pulmonary arterial pressure associated with systemic sclerosis: a randomized, controlled, double-blind, parallel group study (EDITA study).

OBJECTIVE: The objective of this randomized, placebo-controlled, double-blind, parallel group, trial was to assess the effect of ambrisentan on mean pulmonary arterial pressure (mPAP) in patients with systemic sclerosis (SSc) and mildly elevated pulmonary hypertension (PH). METHODS: Thirty-eight SSc patients with mildly elevated mPAP at rest between 21 and 24 mmHg and/or > 30 mmHg during low-dose exercise were randomly assigned to treatment with either ambrisentan 5-10 mg/day or placebo. Right heart catheterization and further clinical parameters were assessed at baseline and after 6 months. The primary endpoint was the difference of mPAP change at rest between groups. RESULTS: After 6 months, the two groups did not differ in the primary endpoint (ambrisentan mPAP - 1 ± 6.4 mmHg vs. placebo - 0.73 ± 3.59 mmHg at rest, p = 0.884). However, three patients from the placebo group but none of the ambrisentan group progressed to SSc-associated pulmonary arterial hypertension. Furthermore, ambrisentan treatment showed significant improvements in the secondary endpoints cardiac index (CI) and pulmonary vascular resistance (PVR) at rest (CI 0.36 ± 0.66 l/min/m2 vs. - 0.31 ± 0.71 l/min/m2, p = 0.010; PVR - 0.70 ± 0.78 WU vs. 0.01 ± 0.71 WU, p = 0.012) and during exercise (CI 0.7 ± 0.81 l/min/m2 vs. - 0.45 ± 1.36 l/min/m2, p = 0.015; PVR - 0.84 ± 0.48 WU vs. - 0.0032 ± 0.34 WU, p < 0.0001). CONCLUSION: This is the first randomized, double-blind, placebo-controlled study testing the effect of ambrisentan in patients with mildly elevated mPAP and/or exercise PH. The primary endpoint change in mPAP did only tendentially improve in the ambrisentan group, but the significant improvement of other hemodynamic parameters points to a possible benefit of ambrisentan and will be helpful to design future trials. TRIAL REGISTRATION: www.ClinicalTrials.gov, unique identifier NCT: NCT02290613 , registered 14th of November 2014.

Reduced Right Ventricular Output Reserve in Patients With Systemic Sclerosis and Mildly Elevated Pulmonary Artery Pressure.

OBJECTIVE: This prospective study was undertaken to evaluate right ventricular function and pulmonary arterial compliance (PAC; ratio of stroke volume to pulse pressure) at rest and during exercise in patients with systemic sclerosis (SSc) with normal mean pulmonary artery pressure (PAP), patients with SSc with mildly elevated mean PAP, and patients with SSc with manifest pulmonary hypertension (PH). METHODS: Patients with SSc (n = 112) underwent clinical assessment and right-sided heart catheterization at rest and during exercise and were divided into 3 groups according to their resting mean PAP values: normal mean PAP (≤20 mm Hg), mildly elevated mean PAP (21-24 mm Hg), and PH (mean PAP ≥25 mm Hg). Results were compared between groups by analysis of variance followed by post hoc Student's t-test. RESULTS: Compared to patients with normal mean PAP, patients with mildly elevated mean PAP had a lower 6-minute walking distance (P = 0.008), lower cardiac index (P = 0.027) and higher pulmonary vascular resistance (P = 0.0002) during exercise, and lower PAC at rest (P = 0.016) and different stages of exercise (P = 0.033 for 25W and P = 0.024 for 75W). CONCLUSION: The results of this study suggest that impaired 6-minute walking distance in SSc patients with mildly elevated mean PAP might be caused by reduced PAC during exercise and reduced right ventricular output reserve, presumably due to impaired coupling between the right ventricle and the pulmonary vasculature. These findings provide further evidence of the clinical relevance of mildly elevated mean PAP in patients with SSc.

Right ventricular size and function under riociguat in pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension (the RIVER study).

BACKGROUND: Riociguat is a soluble guanylate cyclase stimulator approved for pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTPEH). The objective of this study was to evaluate right heart size and function assessed by echocardiography during long term treatment with riociguat. METHODS: Patients who started riociguat treatment (1.0-2.5 mg tid) within the trials phase II, PATENT, PATENTplus, EAS, CHEST and continued treatment for 3-12 months were included in this study. Echocardiography was analysed off-line at baseline, after 3, 6 and 12 months by investigators who were blinded to clinical data. Last and baseline observation carried forward method (LOCF, BOCF) were performed as sensitivity analysis. RESULTS: Seventy-one patients (45% PAH, 55% CTEPH; 53.5% female; 60 ± 13 years, mean pulmonary arterial pressure 46 ± 10 mmHg, mean PVR 700 ± 282dynes·sec·cm-5) were included. After 6 months, RA and RV area, RV thickness tricuspid regurgitation velocity showed a significant reduction. After 12 months, patients receiving riociguat therapy showed a significant reduction in right atrial (- 2.6 ± 4.4 cm2, 95% CI -3.84, - 1.33; p < 0.001, n = 49) and right ventricular (RV) area (- 3.5 ± 5.2 cm2, 95% CI -5.1, - 1.9; p < 0.001; n = 44), RV thickness (- 0.76 ± 2.2 mm, 95% CI -1.55, 0.03; n = 32), and a significant increase in TAPSE (2.95 ± 4.78 mm, 95% CI 1.52, 4.39; n = 45) and RV fractional area change (8.12 ± 8.87 mm, 95% CI 4.61, 11.62; n = 27). Both LOCF and BOCF showed similar results but lower effect sizes. CONCLUSION: Patients under long-term treatment with riociguat show significantly reduced right heart size and improved RV function in PAH and CTEPH. Further controlled prospective studies are needed to confirm these results.