Serum and Pulmonary Expression Profiles of the Activin Signaling System in Pulmonary Arterial Hypertension.

BACKGROUND: Activins are novel therapeutic targets in pulmonary arterial hypertension (PAH). We therefore studied whether key members of the activin pathway could be used as PAH biomarkers. METHODS: Serum levels of activin A, activin B, α-subunit of inhibin A and B proteins, and the antagonists follistatin and follistatin-like 3 (FSTL3) were measured in controls and in patients with newly diagnosed idiopathic, heritable, or anorexigen-associated PAH (n=80) at baseline and 3 to 4 months after treatment initiation. The primary outcome was death or lung transplantation. Expression patterns of the inhibin subunits, follistatin, FSTL3, Bambi, Cripto, and the activin receptors type I (ALK), type II (ACTRII), and betaglycan were analyzed in PAH and control lung tissues. RESULTS: Death or lung transplantation occurred in 26 of 80 patients (32.5%) over a median follow-up of 69 (interquartile range, 50-81) months. Both baseline (hazard ratio, 1.001 [95% CI, 1.000-1.001]; P=0.037 and 1.263 [95% CI, 1.049-1.520]; P=0.014, respectively) and follow-up (hazard ratio, 1.003 [95% CI, 1.001-1.005]; P=0.001 and 1.365 [95% CI, 1.185-1.573]; P<0.001, respectively) serum levels of activin A and FSTL3 were associated with transplant-free survival in a model adjusted for age and sex. Thresholds determined by receiver operating characteristic analyses were 393 pg/mL for activin A and 16.6 ng/mL for FSTL3. When adjusted with New York Heart Association functional class, 6-minute walk distance, and N-terminal pro-B-type natriuretic peptide, the hazard ratios for transplant-free survival for baseline activin A <393 pg/mL and FSTL3 <16.6 ng/mL were, respectively, 0.14 (95% CI, 0.03-0.61; P=0.009) and 0.17 (95% CI, 0.06-0.45; P<0.001), and for follow-up measures, 0.23 (95% CI, 0.07-0.78; P=0.019) and 0.27 (95% CI, 0.09-0.78, P=0.015), respectively. Prognostic values of activin A and FSTL3 were confirmed in an independent external validation cohort. Histological analyses showed a nuclear accumulation of the phosphorylated form of Smad2/3, higher immunoreactivities for ACTRIIB, ALK2, ALK4, ALK5, ALK7, Cripto, and FSTL3 in vascular endothelial and smooth muscle layers, and lower immunostaining for inhibin-α and follistatin. CONCLUSIONS: These findings offer new insights into the activin signaling system in PAH and show that activin A and FSTL3 are prognostic biomarkers for PAH.

Risk stratification and treatment goals in pulmonary arterial hypertension.

Risk stratification has gained an increasing role in predicting outcomes and guiding the treatment of patients with pulmonary arterial hypertension (PAH). The most predictive prognostic factors are three noninvasive parameters (World Health Organization functional class, 6-min walk distance and natriuretic peptides) that are included in all currently validated risk stratification tools. However, suffering from limitations mainly related to reduced specificity of PAH severity, these variables may not always be adequate in isolation for guiding individualised treatment decisions. Moreover, with effective combination treatment regimens and emerging PAH therapies, markers associated with pulmonary vascular remodelling are expected to become of increasing relevance in guiding the treatment of patients with PAH. While reaching a low mortality risk, assessed with a validated risk tool, remains an important treatment goal, preliminary data suggest that invasive haemodynamics and cardiac imaging may add incremental value in guiding treatment decisions.

Characteristics and outcomes of patients developing pulmonary hypertension associated with proteasome inhibitors.

BACKGROUND: Pulmonary arterial hypertension (PAH) has been described in patients treated with proteasome inhibitors (PIs). Our objective was to evaluate the association between PIs and PAH. METHODS: Characteristics of incident PAH cases previously treated with carfilzomib or bortezomib were analysed from the French pulmonary hypertension registry and the VIGIAPATH programme from 2004 to 2023, concurrently with a pharmacovigilance disproportionality analysis using the World Health Organization (WHO) global database (VigiBase) and a meta-analysis of randomised controlled trials. RESULTS: 11 incident cases of PI-associated PAH were identified (six with carfilzomib and five with bortezomib) with a female:male ratio of 2.7:1, a median age of 61 years, and a median delay between PI first exposure and PAH of 6 months. Four patients died (two from right heart failure, one from respiratory distress and one from an unknown cause). At diagnosis, six were in New York Heart Association Functional Class III/IV with severe haemodynamic impairment (median mean pulmonary arterial pressure 39 mmHg, cardiac index 2.45 L·min-1·m-2 and pulmonary vascular resistance 7.2 WU). In the WHO pharmacovigilance database, 169 cases of PH associated with PI were reported since 2013 with significant signals of disproportionate reporting (SDR) for carfilzomib, regardless of the definition of cases or control group. However, SDR for bortezomib were inconsistent. The systematic review identified 17 clinical trials, and carfilzomib was associated with a significantly higher risk of dyspnoea, severe dyspnoea and PH compared with bortezomib. CONCLUSION: PIs may induce PAH in patients undergoing treatment, with carfilzomib emitting a stronger signal than bortezomib, and these patients should be monitored closely.

Risk stratification refinements with inclusion of haemodynamic variables at follow-up in patients with pulmonary arterial hypertension.

BACKGROUND: Haemodynamic variables are prognostic factors in pulmonary arterial hypertension (PAH). However, right heart catheterisation (RHC) is not systematically recommended to assess the risk status during follow-up. This study aimed to assess the added value of haemodynamic variables in prevalent patients to predict the risk of death or lung transplantation according to their risk status assessed by the non-invasive four-strata model as recommended by the European guidelines. METHODS: We evaluated incident patients with PAH enrolled in the French pulmonary hypertension registry between 2009 and 2020 who had a first follow-up RHC. Cox regression identified, in each follow-up risk status, haemodynamic variables significantly associated with transplant-free survival. Optimal thresholds were determined by time-dependent receiver operating characteristics. Several multivariable Cox regression models were performed to identify the haemodynamic variables improving the non-invasive risk stratification model. RESULTS: We analysed 1240 incident patients reassessed within 1 year by RHC. None of the haemodynamic variables were significantly associated with transplant-free survival among low-risk (n=386) or high-risk (n=71) patients. Among patients at intermediate (intermediate-low, n=483 and intermediate-high, n=300) risk at first follow-up, multivariable models including either stroke volume index (SVI) or mixed venous oxygen saturation (S vO2 ) were the best. The prognostic performance of a refined six-strata risk stratification model including the non-invasive four-strata model and SVI >37 mL·m-2 and/or S vO2 >65% for patients at intermediate risk (area under the curve (AUC) 0.81; c-index 0.74) was better than that of the four-strata model (AUC 0.79, p=0.009; c-index 0.72). CONCLUSION: Cardiopulmonary haemodynamics may improve risk stratification at follow-up in patients at intermediate risk.

Clinical Phenotype and Outcomes of Pulmonary Hypertension Associated with Myeloproliferative Neoplasms: A Population-based Study.

Rationale: Precapillary pulmonary hypertension (PH) is a rare and largely unrecognized complication of myeloproliferative neoplasms (MPNs), including polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (MF). Objectives: To describe characteristics and outcomes of MPN-associated PH. Methods: We report clinical, functional, and hemodynamic characteristics, classification, and outcomes of patients with PV, ET, or primary MF in the French PH registry. Measurements and Main Results: Ninety patients with MPN (42 PV, 35 ET, 13 primary MF) presented with precapillary PH with severe hemodynamic impairment, with a median mean pulmonary arterial pressure and pulmonary vascular resistance of 42 mm Hg and 6.7 Wood units, respectively, and impaired clinical conditions, with 71% in New York Heart Association functional classes III/IV and having a median 6-minute-walk distance of 310 m. Half of the patients were diagnosed with chronic thromboembolic PH (CTEPH); the other half were considered to have group 5 PH. MF was preferentially associated with group 5 PH, whereas PV and ET were generally related to CTEPH. Proximal lesions were diagnosed in half of the patients with CTEPH. Thromboendarterectomy was performed in 18 selected patients with high risk of complications (5 early deaths). Overall survival at 1, 3, and 5 years was 67%, 50%, and 34% in group 5 PH and 81%, 66%, and 42% in CTEPH, respectively. Conclusions: PH is a life-threatening condition potentially occurring in MPN. There are multiple mechanisms, with equal diagnoses of CTEPH and group 5 PH. Physicians should be aware that PH strongly affects the burden of patients with MPN, especially in group 5 PH, with unknown pathophysiological mechanisms.

The evolving landscape of pulmonary arterial hypertension clinical trials.

Although it is a rare disease, the number of available therapeutic options for treating pulmonary arterial hypertension has increased since the late 1990s, with multiple drugs developed that are shown to be effective in phase 3 randomised controlled trials. Despite considerable advancements in pulmonary arterial hypertension treatment, prognosis remains poor. Existing therapies target pulmonary endothelial dysfunction with vasodilation and anti-proliferative effects. Novel therapies that target proliferative vascular remodelling and affect important outcomes are urgently needed. There is need for additional innovations in clinical trial design so that all emerging candidate therapies can be rigorously studied. Pulmonary arterial hypertension trial design has shifted from short-term submaximal exercise capacity as a primary endpoint, to larger clinical event-driven trial outcomes. Event-driven pulmonary arterial hypertension trials could face feasibility and efficiency issues in the future because increasing sample sizes and longer follow-up durations are needed, which would be problematic in such a rare disease. Enrichment strategies, innovative and alternative trial designs, and novel trial endpoints are potential solutions that could improve the efficiency of future pulmonary arterial hypertension trials while maintaining robustness and clinically meaningful evidence.

Cytokines as prognostic biomarkers in pulmonary arterial hypertension.

BACKGROUND: Risk stratification and assessment of disease progression in patients with pulmonary arterial hypertension (PAH) are challenged by the lack of accurate disease-specific and prognostic biomarkers. To date, brain natriuretic peptide (BNP) and/or its N-terminal fragment (NT-proBNP) are the only markers for right ventricular dysfunction used in clinical practice, in association with echocardiographic and invasive haemodynamic variables to predict outcome in patients with PAH. METHODS: This study was designed to identify an easily measurable biomarker panel in the serum of 80 well-phenotyped PAH patients with idiopathic, heritable or drug-induced PAH at baseline and at first follow-up. The prognostic value of identified cytokines of interest was secondly analysed in an external validation cohort of 125 PAH patients. RESULTS: Among the 20 biomarkers studied with the multiplex Ella platform, we identified a three-biomarker panel composed of ß-NGF, CXCL9 and TRAIL that were independently associated with prognosis both at the time of PAH diagnosis and at the first follow-up after initiation of PAH therapy. ß-NGF and CXCL9 were predictors of death or transplantation, whereas high levels of TRAIL were associated with a better prognosis. Furthermore, the prognostic value of the three cytokines was more powerful for predicting survival than usual non-invasive variables (New York Heart Association Functional Class, 6-min walk distance and BNP/NT-proBNP). The results were validated in a fully independent external validation cohort. CONCLUSION: The monitoring of ß-NGF, CXCL9 and TRAIL levels in serum should be considered in the management and treatment of patients with PAH to objectively guide therapeutic options.

In-depth characterization of pulmonary arterial hypertension in mixed connective tissue disease: a French national multicentre study.

OBJECTIVE: Pulmonary arterial hypertension (PAH) is a leading cause of death in MCTD. We aimed to describe PAH in well-characterized MCTD patients. METHODS: MCTD patients enrolled in the French Pulmonary Hypertension Registry with a PAH diagnosis confirmed by right heart catheterization were included in the study and compared with matched controls: MCTD patients without PAH, SLE patients with PAH and SSc patients with PAH. Survival rates were estimated by the Kaplan-Meier method and risk factors for PAH in MCTD patients and risk factors for mortality in MCTD-PAH were sought using multivariate analyses. RESULTS: Thirty-six patients with MCTD-PAH were included in the study. Comparison with MCTD patients without PAH and multivariate analysis revealed that pericarditis, polyarthritis, thrombocytopenia, interstitial lung disease (ILD) and anti-Sm antibodies were independent predictive factors of PAH/PH in MCTD. Estimated survival rates at 1, 5 and 10 years following PAH diagnosis were 83%, 67% and 56%, respectively. MCTD-PAH presentation and survival did not differ from SLE-PAH and SSc-PAH. Multivariate analysis revealed that tobacco exposure was an independent factor predictive of mortality in MCTD-PAH. CONCLUSION: PAH is a rare and severe complication of MCTD associated with a 56% 10-year survival. We identified ILD, pericarditis, thrombocytopenia and anti-Sm antibodies as risk factors for PAH in MCTD and tobacco exposure as a predictor of mortality in MCTD-PAH.

Management of Acutely Decompensated Pulmonary Hypertension.

Pulmonary arterial hypertension is a severe life-threatening condition associated with increased pulmonary vascular resistance and resulting right heart dysfunction. Admission to intensive care unit with acutely decompensated right heart failure is a significant negative prognostic event with a high risk of multisystem organ dysfunction and death. Presentations are heterogenous and may combine signs of both diastolic and systolic dysfunction complicating management. Renal dysfunction is often present, but other organ systems can be involved resulting in findings such as acute hepatic dysfunction or bowel wall congestion and ischemia. The goals of therapy are to rapidly reverse ventriculo-arterial decoupling and reduce right ventricular afterload to prevent progression to refractory or irreversible right heart failure. Triggering events must be investigated for and addressed urgently if identified. Volume status management is critical and both noninvasive and invasive testing can aid in prognostication and guide management, including the use of inotropes and vasopressors. In cases of refractory right heart dysfunction, consideration of urgent lung transplantation and mechanical circulatory support is necessary. These patients should be managed at expert centers in an intensive care setting with a multidisciplinary team of practitioners experienced in the management of right heart dysfunction given the high short- and long-term mortality resulting from acute decompensated right heart failure.

Using the Plasma Proteome for Risk Stratifying Patients with Pulmonary Arterial Hypertension.

Rationale: NT-proBNP (N-terminal pro-brain natriuretic peptide), a biomarker of cardiac origin, is used to risk stratify patients with pulmonary arterial hypertension (PAH). Its limitations include poor sensitivity to early vascular pathology. Other biomarkers of vascular or systemic origin may also be useful in the management of PAH. Objectives: Identify prognostic proteins in PAH that complement NT-proBNP and clinical risk scores. Methods: An aptamer-based assay (SomaScan version 4) targeting 4,152 proteins was used to measure plasma proteins in patients with idiopathic, heritable, or drug-induced PAH from the UK National Cohort of PAH (n = 357) and the French EFORT (Evaluation of Prognostic Factors and Therapeutic Targets in PAH) study (n = 79). Prognostic proteins were identified in discovery-replication analyses of UK samples. Proteins independent of 6-minute-walk distance and NT-proBNP entered least absolute shrinkage and selection operator modeling, and the best combination in a single score was evaluated against clinical targets in EFORT. Measurements and Main Results: Thirty-one proteins robustly informed prognosis independent of NT-proBNP and 6-minute-walk distance in the UK cohort. A weighted combination score of six proteins was validated at baseline (5-yr mortality; area under the curve [AUC], 0.73; 95% confidence interval [CI], 0.63-0.85) and follow-up in EFORT (AUC, 0.84; 95% CI, 0.75-0.94; P = 9.96 × 10-6). The protein score risk stratified patients independent of established clinical targets and risk equations. The addition of the six-protein model score to NT-proBNP improved prediction of 5-year outcomes from AUC 0.762 (0.702-0.821) to 0.818 (0.767-0.869) by receiver operating characteristic analysis (P = 0.00426 for difference in AUC) in the UK replication and French samples combined. Conclusions: The plasma proteome informs prognosis beyond established factors in PAH and may provide a more sensitive measure of therapeutic response.

COVID-19 in Patients with Pulmonary Hypertension: A National Prospective Cohort Study.

Rationale: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is associated with pulmonary endothelial dysfunction. There are limited data available on the outcomes of coronavirus disease (COVID-19) in patients with pulmonary hypertension (PH), a disease characterized by pulmonary endothelial dysfunction. Objectives: To describe characteristics and outcomes of patients with precapillary PH and COVID-19. Methods: We prospectively collected characteristics, management, and outcomes of adult patients with precapillary PH in the French PH network who had COVID-19 between February 1, 2020, and April 30, 2021. Clinical, functional, and hemodynamic characteristics of PH before COVID-19 were collected from the French PH registry. Measurements and Main Results: A total of 211 patients with PH (including 123 with pulmonary arterial hypertension, 47 with chronic thromboembolic PH, and 41 with other types of PH) experienced COVID-19, and 40.3% of them were outpatients, 32.2% were hospitalized in a conventional ward, and 27.5% were in an ICU. Among hospitalized patients (n = 126), 54.0% received corticosteroids, 37.3% high-flow oxygen, and 11.1% invasive ventilation. Right ventricular and acute renal failure occurred in 30.2% and 19.8% of patients, respectively. Fifty-two patients (all hospitalized) died from COVID-19. Overall mortality was 24.6% (95% CI [confidence interval], 18.8-30.5) and in-hospital mortality 41.3% (95% CI, 32.7-49.9). Nonsurvivors were significantly older, more frequently male and suffering comorbidities (diabetes, chronic respiratory diseases, systemic hypertension, chronic cardiac diseases, and/or chronic renal failure), and had more severe PH at their most recent evaluation preceding COVID-19 diagnosis (in terms of functional class and 6-minute-walk distance; all P < 0.05). Use of pulmonary arterial hypertension therapy was similar between survivors and nonsurvivors. Conclusions: COVID-19 in patients with precapillary PH was associated with a high in-hospital mortality. The typical risk factors for severe COVID-19 and severity of PH were associated with mortality in this population.

An emerging phenotype of pulmonary arterial hypertension patients carrying SOX17 variants.

BACKGROUND: The phenotype of pulmonary arterial hypertension (PAH) patients carrying SOX17 pathogenic variants remains mostly unknown. METHODS: We report the genetic analysis findings, characteristics and outcomes of patients with heritable PAH carrying SOX17 variants from the French Pulmonary Hypertension Network. RESULTS: 20 patients and eight unaffected relatives were identified. The median (range) age at diagnosis was 17 (2-53) years, with a female:male ratio of 1.5. At diagnosis, most of the patients (74%) were in New York Heart Association Functional Class III or IV with severe haemodynamic compromise, including a median pulmonary vascular resistance of 14.0 (4.2-31.5) WU. An associated congenital heart disease (CHD) was found in seven PAH patients (35%). Patients with CHD-associated PAH were significantly younger at diagnosis than PAH patients without CHD. Four patients (20%) suffered from recurrent haemoptysis requiring repeated arterial embolisations. 13 out of 16 patients (81%) for whom imaging was available displayed chest computed tomography abnormalities, including dilated, tortuous pulmonary vessels, ground-glass opacities as well as anomalies of the bronchial and nonbronchial arteries. After a median (range) follow-up of 47 (1-591) months, 10 patients underwent lung transplantation and one patient benefited from a heart-lung transplantation due to associated CHD. Histopathological analysis of lung explants showed a congested lung architecture with severe pulmonary arterial remodelling, subpleural vessel dilation and numerous haemorrhagic foci. CONCLUSIONS: PAH due to SOX17 pathogenic variants is a severe phenotype, frequently associated with CHD, haemoptysis and radiological abnormalities. Pathological assessment reveals severe pulmonary arterial remodelling and malformations affecting pulmonary vessels and thoracic systemic arteries.

External validation of a refined four-stratum risk assessment score from the French pulmonary hypertension registry.

INTRODUCTION: Contemporary risk assessment tools categorise patients with pulmonary arterial hypertension (PAH) as low, intermediate or high risk. A minority of patients achieve low risk status with most remaining intermediate risk. Our aim was to validate a four-stratum risk assessment approach categorising patients as low, intermediate-low, intermediate-high or high risk, as proposed by the Comparative, Prospective Registry of Newly Initiated Therapies for Pulmonary Hypertension (COMPERA) investigators. METHODS: We evaluated incident patients from the French PAH Registry and applied a four-stratum risk method at baseline and at first reassessment. We applied refined cut-points for three variables: World Health Organization functional class, 6-min walk distance and N-terminal pro-brain natriuretic peptide. We used Kaplan-Meier survival analyses and Cox proportional hazards regression to assess survival according to three-stratum and four-stratum risk approaches. RESULTS: At baseline (n=2879), the four-stratum approach identified four distinct risk groups and performed slightly better than a three-stratum method for predicting mortality. Four-stratum model discrimination was significantly higher than the three-stratum method when applied during follow-up and refined risk categories among subgroups with idiopathic PAH, connective tissue disease-associated PAH, congenital heart disease and portopulmonary hypertension. Using the four-stratum approach, 53% of patients changed risk category from baseline compared to 39% of patients when applying the three-stratum approach. Those who achieved or maintained a low risk status had the best survival, whereas there were more nuanced differences in survival for patients who were intermediate-low and intermediate-high risk. CONCLUSIONS: The four-stratum risk assessment method refined risk prediction, especially within the intermediate risk category of patients, performed better at predicting survival and was more sensitive to change than the three-stratum approach.

Association between Initial Treatment Strategy and Long-Term Survival in Pulmonary Arterial Hypertension.

Rationale: The relationship between the initial treatment strategy and survival in pulmonary arterial hypertension (PAH) remains uncertain. Objectives: To evaluate the long-term survival of patients with PAH categorized according to the initial treatment strategy. Methods: A retrospective analysis of incident patients with idiopathic, heritable, or anorexigen-induced PAH enrolled in the French Pulmonary Hypertension Registry (January 2006 to December 2018) was conducted. Survival was assessed according to the initial strategy: monotherapy, dual therapy, or triple-combination therapy (two oral medications and a parenteral prostacyclin). Measurements and Main Results: Among 1,611 enrolled patients, 984 were initiated on monotherapy, 551 were initiated on dual therapy, and 76 were initiated on triple therapy. The triple-combination group was younger and had fewer comorbidities but had a higher mortality risk. The survival rate was higher with the use of triple therapy (91% at 5 yr) as compared with dual therapy or monotherapy (both 61% at 5 yr) (P < 0.001). Propensity score matching of age, sex, and pulmonary vascular resistance also showed significant differences between triple therapy and dual therapy (10-yr survival, 85% vs. 65%). In high-risk patients (n = 243), the survival rate was higher with triple therapy than with monotherapy or dual therapy, whereas there was no difference between monotherapy and double therapy. In intermediate-risk patients (n = 1,134), survival improved with an increasing number of therapies. In multivariable Cox regression, triple therapy was independently associated with a lower risk of death (hazard ratio, 0.29; 95% confidence interval, 0.11-0.80; P = 0.017). Among the 148 patients initiated on a parenteral prostacyclin, those on triple therapy had a higher survival rate than those on monotherapy or dual therapy. Conclusions: Initial triple-combination therapy that includes parenteral prostacyclin seems to be associated with a higher survival rate in PAH, particularly in the youngest high-risk patients.

Pulmonary Hypertension in Patients with Common Variable Immunodeficiency.

PURPOSE: Common variable immunodeficiency (CVID) is known to cause infectious, inflammatory, and autoimmune manifestations. Pulmonary hypertension (PH) is an unusual complication of CVID with largely unknown characteristics and mechanisms. METHODS: We report the clinical, functional, hemodynamics, radiologic and histologic characteristics, and outcomes of CVID-associated PH patients from the French PH Network. RESULTS: Ten patients were identified. The median (range) age at CVID diagnosis was 36.5 (4-49) years and the median delay between CVID and PH diagnosis was 12 (0-30) years. CVID-associated PH affected predominantly women (female-to-male ratio 9:1). Most patients were New York Heart Association functional class III with a severe hemodynamic profile and frequent portal hypertension (n = 6). Pulmonary function tests were almost normal in 70% of patients and showed a mild restrictive syndrome in 30% of patients while the diffusing capacity for carbon monoxide was decreased in all but one patient. High-resolution computed tomography found enlarged mediastinal nodes, mild interstitial infiltration with reticulations and nodules. Two patients had a CIVD-interstitial lung disease, and one presented with bronchiectasis. Pathologic assessment of lymph nodes performed in 5 patients revealed the presence of granulomas (n = 5) and follicular lymphoid hyperplasia (n = 3). At last follow-up (median 24.5 months), 9 patients were alive, and one patient died of Hodgkin disease. CONCLUSION: PH is a possible complication of CVID whose pathophysiological mechanisms, while still unclear, would be due to the inflammatory nature of CVID. CVID-associated PH presents as precapillary PH with multiple possible causes, acting in concert in some patients: a portal hypertension, a pulmonary vascular remodeling, sometimes a pulmonary parenchymal involvement and occasionally an extrinsic compression by mediastinal lymphadenopathies, which would be consistent with its classification in group 5 of the current PH classification.

Serum and pulmonary uric acid in pulmonary arterial hypertension.

Previous studies have suggested an association between uric acid (UA) and the severity of pulmonary arterial hypertension (PAH), but it is unknown whether UA contributes to disease pathogenesis.The aim of this study was to determine the prognostic value of circulating UA in the era of current management of PAH and to investigate the role of UA in pulmonary vascular remodelling.Serum UA levels were determined in idiopathic, heritable or anorexigen PAH at baseline and first re-evaluation in the French Pulmonary Hypertension Network. We studied protein levels of xanthine oxidase (XO) and the voltage-driven urate transporter 1 (URATv1) in lungs of control and PAH patients and of monocrotaline (MCT) and Sugen/hypoxia (SuHx) rats. Functional studies were performed using human pulmonary artery smooth muscle cells (PA-SMCs) and two animal models of pulmonary hypertension (PH).High serum UA levels at first follow-up, but not at baseline, were associated with a poor prognosis. Both the generating enzyme XO and URATv1 were upregulated in the wall of remodelled pulmonary arteries in idiopathic PAH patients and MCT and SuHx rats. High UA concentrations promoted a mild increase in cell growth in idiopathic PAH PA-SMCs, but not in control PA-SMCs. Consistent with these observations, oxonic acid-induced hyperuricaemia did not aggravate MCT-induced PH in rats. Finally, chronic treatment of MCT and SuHx rats with benzbromarone mildly attenuated pulmonary vascular remodelling.UA levels in idiopathic PAH patients were associated with an impaired clinical and haemodynamic profile and might be used as a non-invasive indicator of clinical prognosis during follow-up. Our findings also indicate that UA metabolism is disturbed in remodelled pulmonary vascular walls in both experimental and human PAH.

Intensity and quality of exertional dyspnoea in patients with stable pulmonary hypertension.

Dynamic hyperinflation is observed during exercise in 60% of patients with clinically stable pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH), intensifying exertional dyspnoea. The impact of dynamic changes in respiratory mechanics during exercise on qualitative dimensions of dyspnoea in these patients has not been evaluated.26 patients (PAH n=17; CTEPH n=9) performed an incremental symptom-limited cycle exercise test. Minute ventilation (V'E), breathing pattern, operating lung volumes and dyspnoea intensity were assessed throughout exercise. Dyspnoea quality was serially assessed during exercise using a three-item questionnaire (dyspnoea descriptors). The inflection point of tidal volume (V T) relative to V'E was determined for each incremental test. Changes in inspiratory capacity during exercise defined two groups of patients: hyperinflators (65%) and non-hyperinflators (35%). Multidimensional characterisation of dyspnoea was performed after exercise using the Multidimensional Dyspnea Profile.In hyperinflators, inspiratory capacity decreased progressively throughout exercise by 0.36 L, while remaining stable in non-hyperinflators. The "work/effort" descriptor was most frequently selected throughout exercise in both types of patients (65% of all responses). At the V T/V'E inflection, work/effort plateaued while "unsatisfied inspiration" descriptors became selected predominantly only in hyperinflators (77% of all responses). In the affective domain, the emotion most frequently associated with dyspnoea was anxiety.In pulmonary hypertension patients who develop hyperinflation during exercise, dyspnoea descriptors referring to unsatisfied inspiration become predominant following the V T/V'E inflection. As these descriptors are generally associated with more negative emotional experiences, delaying or preventing the V T/V'E inflection may have important implications for symptom management in patients with pulmonary hypertension.

Characteristics and outcomes of asthmatic patients with COVID-19 pneumonia who require hospitalisation.

BACKGROUND: Viral respiratory infections are the main causes of asthma exacerbation. The susceptibility of patients with asthma to develop an exacerbation when they present with severe pneumonia due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is unknown. The objective of this study was to investigate the characteristics and outcomes of asthmatic patients with coronavirus disease 2019 (COVID-19) pneumonia who required hospitalisation during the spring 2020 outbreak in Paris, France. METHODS: A prospective cohort follow-up was carried out from 15 March to 15 April 2020 in Bicêtre Hospital, University Paris-Saclay, France. All hospitalised patients with a SARS-CoV-2 infection who reported a history of asthma were included. RESULTS: Among 768 hospitalised patients, 37 (4.8%) reported a history of asthma, which had been previously confirmed by a pulmonologist in 85% of cases. These asthmatic patients were mainly female (70%) and nonsmokers (85%), with a median age of 54 years (interquartile range (IQR) 42-67 years). None of them presented with an asthma exacerbation. 22 (59%) had major comorbidities and 31 (84%) had a body mass index ≥25 kg·m-2. The most common comorbidities were obesity (36%), hypertension (27%) and diabetes (19%). All patients had a confirmed diagnosis of COVID-19 pneumonia on computed tomography of the chest. Eosinopenia was a typical biological feature with a median count of 0 cells·mm-3 (IQR 0-0 cells·mm-3). 11 patients (30%) were admitted into the intensive care unit, with three deaths (8.1%) occurring in the context of comorbidities. CONCLUSION: Asthma patients were not overrepresented among those with severe pneumonia due to SARS-CoV-2 infection who required hospitalisation. The worst outcomes were observed mainly in patients with major comorbidities.

Prognostic Value of Follow-Up Hemodynamic Variables After Initial Management in Pulmonary Arterial Hypertension.

BACKGROUND: Hemodynamic variables such as cardiac index and right atrial pressure have consistently been associated with survival in pulmonary arterial hypertension (PAH) at the time of diagnosis. Recent studies have suggested that pulmonary arterial compliance may also predict prognosis in PAH. The prognostic importance of hemodynamic values achieved after treatment initiation is less well established. METHODS: Our objective was to evaluate the prognostic importance of clinical and hemodynamic variables during follow-up, including pulmonary arterial compliance, after initial management in PAH. We evaluated incident patients with idiopathic, drug- and toxin-induced, or heritable PAH enrolled in the French pulmonary hypertension registry between 2006 and 2016 who had a follow-up right-sided heart catheterization (RHC). The primary outcome was death or lung transplantation. We used stepwise Cox regression and the Kaplan-Meier method to assess variables obtained at baseline and at first follow-up RHC. RESULTS: Of 981 patients, a primary outcome occurred in 331 patients (33.7%) over a median follow-up duration of 2.8 years (interquartile range, 1.1-4.6 years). In a multivariable model considering only baseline variables, no hemodynamic variables independently predicted prognosis. Median time to first follow-up RHC was 4.6 months (interquartile range, 3.7-7.8 months). At first follow-up RHC (n=763), New York Heart Association functional class, 6-minute walk distance, stroke volume index (SVI), and right atrial pressure were independently associated with death or lung transplantation, adjusted for age, sex, and type of PAH. Pulmonary arterial compliance did not independently predict outcomes at baseline or during follow-up. The adjusted hazard ratio for SVI was 1.28 (95% confidence interval, 1.11-1.49; P<0.01) per 10-mL/m2 decrease and for right atrial pressure was 1.05 (95% confidence interval, 1.02-1.09; P<0.01) per 1-mm Hg increase. Among patients who had 2 (n=355) or 3 (n=193) low-risk prognostic features at follow-up, including a cardiac index ≥2.5 L·min-1·m-2, 6-minute walk distance >440 m, and New York Heart Association class I or II functional class, lower SVI was still associated with higher rates of death or lung transplantation (P<0.01). CONCLUSIONS: SVI and right atrial pressure were the hemodynamic variables that were independently associated with death or lung transplantation at first follow-up RHC after initial PAH treatment. These findings suggest that the SVI could be a more appropriate treatment target than cardiac index in PAH.

Aztreonam plus Clavulanate, Tazobactam, or Avibactam for Treatment of Infections Caused by Metallo-ß-Lactamase-Producing Gram-Negative Bacteria.

Metallo-ß-lactamase (MBL)-producing Gram-negative bacteria are often extremely resistant, leading to a real therapeutic dead end. Here, we evaluated the in vitro and in vivo efficacy of aztreonam in combination with ceftazidime-avibactam, ceftolozane-tazobactam, or amoxicillin-clavulanate for the treatment of infections caused by MBL-producing Enterobacteriaceae, MBL-producing Pseudomonas aeruginosa, and extremely drug-resistant Stenotrophomonas maltophilia First, we report two clinical cases, namely, a urinary tract infection caused by an NDM-5-producing Escherichia coli isolate and a pulmonary infection caused by a S. maltophilia isolate efficiently treated with the association of aztreonam-ceftazidime-avibactam and aztreonam-amoxicillin-clavulanate, respectively. Then, a total of 50 MBL-producing Enterobacteriaceae isolates, 3 MBL-producing P. aeruginosa isolates, and 5 extremely drug-resistant S. maltophilia isolates were used to test aztreonam susceptibility in combination with ceftolozane-tazobactam, ceftazidime-avibactam, or amoxicillin-clavulanate. The Etest strip superposition method was used to determine the MICs of the aztreonam/inhibitor combinations. According to CLSI breakpoints, aztreonam susceptibility was fully restored for 86%, 20%, and 50% of the MBL-producing Enterobacteriaceae isolates when combined with ceftazidime-avibactam, ceftolozane-tazobactam, and amoxicillin-clavulanate, respectively. In P. aeruginosa, the aztreonam-ceftazidime-avibactam combination was the most potent, even though the reduction in MICs was at most 2-fold. With the 5 S. maltophilia isolates, aztreonam-ceftazidime-avibactam and aztreonam-amoxicillin-clavulanate were found to be equal (100% susceptibility). Overall, aztreonam-ceftazidime-avibactam was the most potent combination to treat infections caused by MBL producers compared with aztreonam-amoxicillin-clavulanate and aztreonam-ceftolozane-tazobactam. However, in many cases aztreonam-amoxicillin-clavulanate was found to be as efficient as aztreonam-ceftazidime-avibactam, offering the main advantage to be markedly cheaper. We also confirmed the validity of Etest superpositions as a very simple method to determine MICs of aztreonam combinations.