Clinical phenotypes and outcomes of precapillary pulmonary hypertension of sickle cell disease.

RATIONALE: Precapillary pulmonary hypertension (PH) is a devastating complication of sickle cell disease (SCD). Little is known about the influence of the SCD genotype on PH characteristics. OBJECTIVES: To describe clinical phenotypes and outcomes of precapillary PH due to SCD according to disease genotype. METHODS: A nationwide multicentre retrospective study including all patients with SCD-related precapillary PH from the French PH Registry was conducted. Clinical characteristics and outcomes according to SCD genotype were analysed. RESULTS: 58 consecutive SCD patients with precapillary PH were identified, of whom 41 had homozygous for haemoglobin S (SS) SCD, three had S-ß0 thalassaemia (S-ß0 thal) and 14 had haemoglobin SC disease (SC). Compared to SC patients, SS/S-ß0 thal patients were characterised by lower 6-min walk distance (p=0.01) and lower pulmonary vascular resistance (p=0.04). Mismatched segmental perfusion defects on lung scintigraphy were detected in 85% of SC patients and 9% of SS/S-ß0 thal patients, respectively, and 50% of SS/S-ß0 thal patients had heterogeneous lung perfusion without segmental defects. After PH diagnosis, 31 patients (53%) received medical therapies approved for pulmonary arterial hypertension, and chronic red blood cell exchange was initiated in 23 patients (40%). Four patients were managed for chronic thromboembolic PH by pulmonary endarterectomy (n=1) or balloon pulmonary angioplasty (n=3). Overall survival was 91%, 80% and 60% at 1, 3 and 5 years, respectively, without influence of genotype on prognosis. CONCLUSIONS: Patients with precapillary PH related to SCD have a poor prognosis. Thrombotic lesions appear as a major component of PH related to SCD, more frequently in SC patients.

Long-term outcomes of dasatinib-induced pulmonary arterial hypertension: a population-based study.

This study aimed to describe the long-term outcomes of pulmonary arterial hypertension (PAH) induced by dasatinib.21 incident, right heart catheterisation-confirmed cases of dasatinib-induced PAH were identified from the French Pulmonary Hypertension Registry. Clinical and haemodynamic variables were compared from baseline to last follow-up (median (range) 24 (1-81) months).Median age was 52 years and 15 patients were female (71%). 19 patients received dasatinib for chronic myelogenous leukaemia for a median (range) duration of 42 (8-74) months before PAH diagnosis. No bone morphogenic protein receptor-2 (BMPR2) mutations were found in the 10 patients tested. Dasatinib was uniformly discontinued and 11 patients received PAH medications. Four patients died during follow-up. New York Heart Association functional class improved from 76% in class III/IV to 90% in class I/II (p<0.01). Median (range) 6-min walk distance improved from 306 (0-660) to 430 (165-635) m (p<0.01). Median (range) mean pulmonary arterial pressure improved from 45 (30-70) to 26 (17-50) mmHg (p<0.01) and pulmonary vascular resistance from 6.1 (3.2-27.3) to 2.6 (1.2-5.9) Wood units (p<0.01). Patients treated with PAH medications had worse baseline haemodynamics but similar long-term outcomes to untreated patients. PAH persisted in 37% of patients.Dasatinib-induced PAH frequently improves after discontinuation but persisted in over one-third of patients, therefore systematic follow-up is essential.

A prospective study of the 6†min walk test as a surrogate marker for haemodynamics in two independent cohorts of treatment-naïve systemic sclerosis-associated pulmonary arterial hypertension.

OBJECTIVES: Despite the wide use of the 6 min walk distance (6MWD), no study has ever assessed its validity as a surrogate marker for haemodynamics and predictor of outcome in isolated pulmonary arterial hypertension associated with systemic sclerosis (SSc-PAH). We designed this work to address this issue. METHODS: Treatment-naïve patients with SSc-PAH were prospectively included from two sources: the French PAH Network (a prospective epidemiological cohort) (n=83) and randomised clinical trials submitted for drug approval (Food and Drug Administration) (n=332). Correlations between absolute values of the 6MWD and haemodynamics at baseline, as well as between variations of 6MWD and haemodynamics during follow-up, were studied in both populations. RESULTS: In the French cohort, baseline cardiac output (CO) (R(2)=0.19, p=0.001) and New York Heart Association class (R(2)=0.10, p<0.001) were significantly and independently correlated with baseline 6MWD in multivariate analysis. A significant, independent, but weaker, correlation with CO was also found in the Food and Drug Administration sample (R(2)=0.04, p<0.001). During follow-up, there was no association between the changes in 6MWD and haemodynamic parameters in patients under PAH-specific treatments. CONCLUSIONS: In SSc-PAH, CO independently correlates with 6MWD at baseline, but accounts for a small amount of the variance of 6MWD in both study samples. This suggests that other non-haemodynamic factors could have an impact on the walk distance. Moreover, variations of 6MWD do not reflect changes in haemodynamics among treated patients. Our results suggest that 6MWD is not an accurate surrogate marker for haemodynamic severity, nor an appropriate outcome measure to assess changes in haemodynamics during follow-up in treated SSc-PAH.

Right Heart Hemodynamics in Pulmonary Hypertension　- An Echocardiography and Catheterization Study.

BACKGROUND: Echocardiography (ECHO) plays a key role in both the diagnosis and prognosis of pulmonary hypertension (PH). Many equations have been published to assess right heart hemodynamics using ECHO. The objective of this study was to test the accuracy and precision of different echocardiographic equations in comparison with the right heart catheterization. METHODS AND RESULTS: Complete right heart hemodynamic assessments were prospectively obtained from 115 individuals (mean age 66±1 years; 57 males) who had known or suspected PH. Several equations were tested for the estimation of right atrial pressure, mean and systolic pulmonary artery pressure (MPAP), cardiac output, pulmonary capillary wedge pressure (PCWP), and pulmonary vascular resistance (PVR). The accuracy of ECHO was good, with a mean difference <2 mmHg for all of the pressure calculations and ±0.6 L/min for cardiac output. However, the PVR estimation was weak using any one of the formulae. For all the parameters, the precision of ECHO was moderate. The MPAP calculation detected PH with a sensibility of 97% and specificity of 83%. However, ECHO underdiagnosed post-capillary PH. CONCLUSIONS: ECHO is a good method for the diagnosis of PH, with an adequate calculation of right pressures, but cannot accurately calculate PCWP and PVR. (Circ J 2016; 80: 2019-2025).

Pulmonary Arterial Hypertension-Specific Drug Therapy in COPD Patients with Severe Pulmonary Hypertension and Mild-to-Moderate Airflow Limitation.

BACKGROUND: Patients with severe pulmonary hypertension (PH) associated with chronic obstructive pulmonary disease (COPD) present a poor outcome. Specific PH treatment could improve the clinical and hemodynamic status of these patients but may worsen arterial blood gases. OBJECTIVES: Our study retrospectively included 28 patients with severe precapillary PH (mean pulmonary arterial pressure >35 mm Hg) associated with mild-to-moderate COPD [forced expiratory volume in 1 s (FEV1) >50% predicted]. All patients underwent specific pulmonary arterial hypertension (PAH) treatment as mono-, bi- or triple therapy. METHODS: Our single-center study was conducted based on retrospective data of 537 right heart catheterizations (RHCs) performed on patients with COPD from January 2004 to June 2014. An echocardiography, comprehensive blood tests, pulmonary function tests, and a high-resolution computed tomography were performed before the RHCs. All patients underwent RHC with a Swan-Ganz catheter. RESULTS: Compared to baseline, patients treated with specific PAH drugs showed a significant increase in cardiac index at long term (2.5 ± 0.7 liters/min/m2 at baseline vs. 3.2 ± 0.6 liters/min/m2 at 6/12 months; p = 0.003) as well as a decrease in pulmonary vascular resistance in the long term (8.4 ± 4.2 Wood units at baseline vs. 5 ± 1.7 Wood units at 6/12 months; p = 0.008). There was a slight decrease in arterial oxygen tension (PaO2) after 3 months of treatment (-2.4 ± 7.21 mm Hg; p = 0.066). During a median follow-up of 3 years, 12 patients (42.8%) died (including all causes of death). CONCLUSIONS: This preliminary report suggests that the use of specific PH therapy in severe PH associated with mild-to-moderate COPD can improve pulmonary hemodynamic parameters, with worsening of PaO2, which had no clinical significance and did not lead to specific PAH therapy withdrawal in any patient.

Survival and response to pulmonary vasodilator therapies in patients with chronic obstructive pulmonary disease and pulmonary vascular phenotype.

BACKGROUND: The aim of the study was to describe and investigate the effect of pulmonary arterial hypertension (PAH) therapies in a cohort of patients with severe precapillary pulmonary hypertension (PH) associated with chronic obstructive pulmonary disease (COPD; PH-COPD), and to assess factors predictive of treatment response and mortality. MATERIAL AND METHODS: We retrospectively included patients with severe incident PH-COPD who received PAH therapy and underwent RHC at diagnosis and on treatment. RESULTS: From 2015 to 2022, 35 severe PH-COPD patients, with clinical features of pulmonary vascular phenotype, were included. Seventeen (48.5%) patients were treated with combined PAH therapy. PAH therapy led to a significant improvement in hemodynamics (PVR -3.5 Wood Units (-39.3%); p < 0.0001), and in the simplified four-strata risk-assessment score, which improved by at least one category in 21 (60%) patients. This effect was more pronounced in patients on dual therapy. Kaplan-Meier estimated survival rates at 1, 3 and 5 years were 94%, 65% and 42% respectively. Univariate analysis showed a significant reduction in survival in patients with a higher simplified risk score at follow-up (Hazard ratio (HR) 2.88 [1.16-7.15]; p = 0.02). Hypoxemia <50 mmHg was correlated to mortality in multivariate analysis (HR 4.33 [1.08-17.42]; p = 0.04). CONCLUSIONS: Our study confirms the poor prognosis of patients with COPD and a pulmonary vascular phenotype and the potential interest of combined PAH therapy in this population, with good tolerability and greater clinical and hemodynamic improvement than monotherapy. Using the simplified risk score during follow-up could be of interest in this population.

Pulmonary arterial hypertension in patients treated by dasatinib.

BACKGROUND: The French pulmonary hypertension (PH) registry allows the survey of epidemiological trends. Isolated cases of precapillary PH have been reported in patients who have chronic myelogenous leukemia treated with the tyrosine kinase inhibitor dasatinib. METHODS AND RESULTS: This study was designed to describe incident cases of dasatinib-associated PH reported in the French PH registry. From the approval of dasatinib (November 2006) to September 30, 2010, 9 incident cases treated by dasatinib at the time of PH diagnosis were identified. At diagnosis, patients had moderate to severe precapillary PH with functional and hemodynamic impairment. No other incident PH cases were exposed to other tyrosine kinase inhibitors at the time of PH diagnosis. Clinical, functional, or hemodynamic improvements were observed within 4 months of dasatinib discontinuation in all but 1 patient. Three patients required PH treatment with endothelin receptor antagonist (n=2) or calcium channel blocker (n=1). After a median follow-up of 9 months (min-max 3-36), the majority of patients did not demonstrate complete clinical and hemodynamic recovery, and no patients reached a normal value of mean pulmonary artery pressure (≤20 mm Hg). Two patients (22%) died at follow-up (1 of unexplained sudden death and 1 of cardiac failure in the context of septicemia, respectively, 8 and 12 months after dasatinib withdrawal). The lowest estimate of incident PH occurring in patients exposed to dasatinib in France was 0.45%. CONCLUSIONS: Dasatinib may induce severe precapillary PH fulfilling the criteria of pulmonary arterial hypertension, thus suggesting a direct and specific effect of dasatinib on pulmonary vessels. Improvement is usually observed after withdrawal of dasatinib.

Pulmonary hypertension in antisynthetase syndrome: prevalence, aetiology and survival.

Antisynthetase syndrome is characterised by the association of interstitial lung disease and myositis with different anti-tRNA-synthetase antibodies. The occurrence, aetiology and prognosis of pulmonary hypertension have not yet been evaluated. Among 203 consecutive patients, transthoracic echocardiogram and right heart catheterisation results were retrospectively analysed in the light of clinico-biological, morphological and functional parameters. Definitions of pulmonary hypertension were based on the European Society of Cardiology/European Respiratory Society 2009 guidelines, with severe pulmonary hypertension being defined by a mean pulmonary arterial pressure >35 mmHg. Pulmonary hypertension was suspected by transthoracic echocardiogram in 47 (23.2%) cases, corresponding to pulmonary hypertension "possible" (n=27, 13.3%) or "likely" (n=20, 9.9%). Right heart catheterisation was performed in 21 patients, excluding pulmonary hypertension in five and confirming pre-capillary pulmonary hypertension in 16 (7.9%). Although related to interstitial lung disease in all cases, pre-capillary pulmonary hypertension was severe in 13 (81.3%) patients (mean ± sd pulmonary arterial pressure 46 ± 9 mmHg), frequently associated with low cardiac index (mean ± sd 2.3 ± 0.8 L · min(-1) · m(-2)) and high forced vital capacity/diffusing capacity of the lung for carbon monoxide ratio (2.5 ± 0.6). Pulmonary hypertension was significantly associated with a lower survival rate (p<0.001), with a 3-year survival rate of 58%. The occurrence of pulmonary hypertension in antisynthetase syndrome is significant and dramatically worsens the prognosis. Although systematically associated with interstitial lung disease, pulmonary hypertension was usually severe, suggesting a specific pulmonary vascular involvement.

Cold ischemia with selective anterograde in situ pulmonary perfusion preserves gas exchange and mitochondrial homeostasis and curbs inflammation in an experimental model of donation after cardiac death.

The aim of this study was to assess the functional preservation of the lung graft with anterograde lung perfusion in a model of donation after cardiac death. Thirty minutes after cardiac arrest, in situ anterograde selective pulmonary cold perfusion was started in six swine. The alveolo-capillary membrane was challenged at 3, 6, and 8 h with measurements of the mean pulmonary arterial pressure (mPAP), the pulmonary vascular resistance (PVR), the PaO2 /FiO2 ratio, the transpulmonary oxygen output (tpVO2 ), and the transpulmonary CO2 clearance (tpCO2 ). Mitochondrial homeostasis was investigated by measuring maximal oxidative capacity (Vmax ) and the coupling of phosphorylation to oxidation (ACR, acceptor control ratio) in lung biopsies. Inflammation and induction of primary immune response were assessed by measurement of tumor necrosis factor alpha (TNFα), interleukine-6 (IL-6) and receptor for advanced glycation endproducts (RAGE) in bronchoalveolar lavage fluid. Data were compared using repeated measures Anova. Pulmonary hemodynamics (mPAP: P = 0.69; PVR: P = 0.46), oxygenation (PaO2 /FiO2 : P = 0.56; tpVO2 : P = 0.46), CO2 diffusion (tpCO2 : P = 0.24), mitochondrial homeostasis (Vmax : P = 0.42; ACR: P = 0.8), and RAGE concentrations (P = 0.24) did not significantly change up to 8 h after cardiac arrest. TNFα and IL-6 were undetectable. Unaffected pulmonary hemodynamics, sustained oxygen and carbon dioxide diffusion, preserved mitochondrial homeostasis, and lack of inflammation suggest a long-lasting functional preservation of the graft with selective anterograde in situ pulmonary perfusion.

Balloon pulmonary angioplasty versus riociguat for the treatment of inoperable chronic thromboembolic pulmonary hypertension (RACE): a multicentre, phase 3, open-label, randomised controlled trial and ancillary follow-up study.

BACKGROUND: Riociguat and balloon pulmonary angioplasty (BPA) are treatment options for inoperable chronic thromboembolic pulmonary hypertension (CTEPH). However, randomised controlled trials comparing these treatments are lacking. We aimed to evaluate the efficacy and safety of BPA versus riociguat in patients with inoperable CTEPH. METHODS: In this phase 3, multicentre, open-label, parallel-group, randomised controlled trial done in 23 French centres of expertise for pulmonary hypertension, we enrolled treatment-naive patients aged 18-80 years with newly diagnosed, inoperable CTEPH and pulmonary vascular resistance of more than 320 dyn·s/cm5. Patients were randomly assigned (1:1) to BPA or riociguat via a web-based randomisation system, with block randomisation (block sizes of two or four patients) without stratification. The primary endpoint was change in pulmonary vascular resistance at week 26, expressed as percentage of baseline pulmonary vascular resistance in the intention-to-treat population. Safety analyses were done in all patients who received at least one dose of riociguat or had at least one BPA session. Patients who completed the RACE trial continued into an ancillary 26-week follow-up during which symptomatic patients with pulmonary vascular resistance of more than 320 dyn·s/cm5 benefited from add-on riociguat after BPA or add-on BPA after riociguat. This trial is registered at ClinicalTrials.gov, NCT02634203, and is completed. FINDINGS: Between Jan 19, 2016, and Jan 18, 2019, 105 patients were randomly assigned to riociguat (n=53) or BPA (n=52). At week 26, the geometric mean pulmonary vascular resistance decreased to 39·9% (95% CI 36·2-44·0) of baseline pulmonary vascular resistance in the BPA group and 66·7% (60·5-73·5) of baseline pulmonary vascular resistance in the riociguat group (ratio of geometric means 0·60, 95% CI 0·52-0·69; p<0·0001). Treatment-related serious adverse events occurred in 22 (42%) of 52 patients in the BPA group and five (9%) of 53 patients in the riociguat group. The most frequent treatment-related serious adverse events were lung injury (18 [35%] of 52 patients) in the BPA group and severe hypotension with syncope (two [4%] of 53 patients) in the riociguat group. There were no treatment-related deaths. At week 52, a similar reduction in pulmonary vascular resistance was observed in patients treated with first-line riociguat or first-line BPA (ratio of geometric means 0·91, 95% CI 0·79-1·04). The incidence of BPA-related serious adverse events was lower in patients who were pretreated with riociguat (five [14%] of 36 patients vs 22 [42%] of 52 patients). INTERPRETATION: At week 26, pulmonary vascular resistance reduction was more pronounced with BPA than with riociguat, but treatment-related serious adverse events were more common with BPA. The finding of fewer BPA-related serious adverse events among patients who were pretreated with riociguat in the follow-up study compared with those who received BPA as first-line treatment points to the potential benefits of a multimodality approach to treatment in patients with inoperable CTEPH. Further studies are needed to explore the effects of sequential treatment combining one or two medications and BPA in patients with inoperable CTEPH. FUNDING: Programme Hospitalier de Recherche Clinique of the French Ministry of Health and Bayer HealthCare. TRANSLATION: For the French translation of the abstract see Supplementary Materials section.

Primary Hepatic Lymphoma After Lung Transplantation: A Report of 2 Cases.

BACKGROUND: Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin lymphoma in the posttransplant setting. Treatment is based on chemotherapy; surgery is still debated and should be performed in very select cases. METHODS: We observed 2 patients out of 300 who underwent lung transplantation in the Nouvel Hopital Civil between 2013 and 2019 with primary hepatic lymphoma. Chemotherapy with a rituximab-cyclophosphamide, hydroxydaunorubicin, vincristine, prednisone protocol was performed in all patients. Mycophenolate mofetil was interrupted before treatment, and everolimus was introduced after chemotherapy by associating tacrolimus withdrawal. RESULTS: One patient showed complete remission; after 7 years, no recurrence has been noticed. The second is still undergoing chemotherapy with no signs of disease progression. CONCLUSIONS: DLBCL risk is higher in solid organ transplant recipients than in the general population. Primary hepatic lymphoma diagnosis is often difficult and based on histologic findings after initial clinical and radiological suspicion of primary or secondary liver neoplasia. Diagnosis is challenging because no clinical, radiological, or biological features exist. Biopsy is always indicated for histologic confirmation. Chemotherapy is the mainstay of therapy, but surgery may be indicated in very select patients.

Biallelic RFC1-expansion in a French multicentric sporadic ataxia cohort.

OBJECTIVE: Cerebellar ataxia with neuropathy and vestibular areflexia syndrome (CANVAS) is a recessively inherited multisystem ataxia compromising cerebellar, vestibular, and sensory nerves, which has been associated to a pathogenic AAGGG(n) biallelic expansion repeat in the RFC1 gene. Our objective was to assess its prevalence in a French cohort of patients with idiopathic sporadic late-onset ataxia (ILOA), idiopathic early-onset ataxia (IEOA), or Multiple System Atrophy of Cerebellar type (MSA-C). METHODS: 163 patients were recruited in 3 French tertiary centers: 100 ILOA, 21 IEOA, and 42 patients with possible or probable MSA-C. RESULTS: A pathogenic biallelic RFC1 AAGGG(n) repeat expansion was found in 15 patients: 15/100 in the ILOA group, but none in the IEOA and MSA-C subgroups. 14/15 patients had a CANVAS phenotype. Only 1/15 had isolated cerebellar ataxia, but also shorter biallelic expansions. Two RFC1 AAGGG(n) alleles were found in 78% of patients with a CANVAS phenotype. In one post-mortem case, the pathophysiological involvement of cerebellum and medullar posterior columns was found. CONCLUSION: Our study confirms the genetic heterogeneity of the CANVAS and that RFC1 repeat expansions should be searched for preferentially in case of unexplained ILOA associated with a sensory neuronopathy, but not particularly in patients classified as MSA-C.

Acute renal failure in systemic sclerosis revealing Goodpasture syndrome: "All that glitters is not scleroderma renal crisis".

The most common cause of acute renal failure in systemic sclerosis patients is scleroderma renal crisis but other etiologies have to be considered such as another autoimmune disease. We report the case of a 60-year-old male admitted to our hospital with a renal failure. His medical history included a diagnosis of systemic sclerosis 6 months ago. Antinuclear antibodies were positive at a titer of 1:1280 with positive anti-Scl-70 and anti-myeloperoxidase (34 U/mL) antibodies. Scleroderma renal crisis was suspected. However, antineutrophil cytoplasmic antibody-associated vasculitis could not be excluded and a renal biopsy was performed. Histopathology revealed crescentic glomerulonephritis and rupture of Bowman's capsule. Anti-glomerular basement membrane antibodies were detected in serum and the diagnosis of Goodpasture syndrome was confirmed by kidney's immunofluorescence analysis showing typical deposits. Only three other cases of systemic sclerosis associated with Goodpasture syndrome have been reported in the literature. Also, rapidly progressive glomerulonephritis with positivity of both antineutrophil cytoplasmic antibody and anti-glomerular basement membrane antibodies has been described. Several studies have suggested that antineutrophil cytoplasmic antibody positivity occurs first leading to damages of the glomerular basement membrane, to the release of alpha-3 NC1 antigen, and ultimately to anti-glomerular basement membrane antibody production. Although rare, antineutrophil cytoplasmic antibody-associated vasculitis and Goodpasture syndrome should be searched for in systemic sclerosis patients with acute renal failure.

T1 mapping cardiac magnetic resonance imaging frequently detects subclinical diffuse myocardial fibrosis in systemic sclerosis patients.

OBJECTIVES: cardiac involvement is the second most frequent systemic sclerosis (SSc) related cause of death. It remains mostly asymptomatic in the early stage and is underdiagnosed with routine screening. Cardiac magnetic resonance imaging (CMR) could improve cardiac assessment of patients and noteworthily, new sequences allow the detection of diffuse myocardial fibrosis (DMF) by native T1 mapping. The aim of this study was to determine the prevalence of cardiac involvement by CMR native T1 mapping and its correlation with echocardiography data and non-cardiac manifestations in SSc patients. METHODS: patients fulfilling the ACR/EULAR classification criteria for SSc were prospectively included between 2014 and 2016. They underwent CMR at 1.5T, including native T1 and T2 mapping, and Late Gadolinium Enhancement (LGE) as a part of routine follow up. Routine biological tests (mainly BNP and CRP) were centralized in the hospital laboratory. RESULTS: seventy-two unselected patients were included. Thirty six patients (50%) had elevated T1 (ET1) (mean T1 1097±14 ms). CMR cardiac functional parameters were similar in ET1 and normal T1 (NT1). Echocardiography was normal in 18 (50%) of ET1. ET1 and NT1 groups were similar for cardiovascular risk factors and ischemic heart disease. ET1 was not correlated with any clinical or echocardiographic parameter or antibody profile. Thirty-six percent of patients with ET1 had no cardiac symptoms, normal echocardiography and CMR LVEF, and no LGE. CONCLUSION: native T1 mapping detects left ventricular ET1 (potential DMF) in 50% of patients with SSc and a third of them had a normal conventional screening including standard CMR. In the future, further studies are needed to confirm the benefit of use of native T1 mapping as a part of routine follow up to detect earlier pejorative cardiac involvement in SSc patients.

Pulmonary hypertension in chronic obstructive pulmonary disease and interstitial lung diseases.

Pulmonary hypertension (PH) is a common complication of chronic respiratory diseases and particularly of chronic obstructive pulmonary disease (COPD) and interstitial lung diseases (ILD). Owing to its frequency COPD is by far the most common cause of PH. It is generally a mild to moderate PH, pulmonary artery mean pressure (PAP) usually ranging between 20 and 25 mm Hg, but PH may worsen during exercise, sleep, and particularly during exacerbations of the disease. These acute increases in PAP may lead to the development of right heart failure. A small proportion of COPD patients may present "disproportionate" PH defined by a resting PAP >35 to 40 mm Hg. The prognosis is particularly poor in these patients. PH is relatively frequent in advanced ILD and particularly in idiopathic pulmonary fibrosis. As in COPD the diagnosis is suggested by Doppler echocardiography, but the confirmation still requires right heart catheterization. As in COPD, functional (alveolar hypoxia) and morphological factors (vascular remodeling, destruction of the pulmonary parenchyma) explain the elevation of pulmonary vascular resistance that leads to PH. Also as in COPD PH is most often mild to moderate. In ILD the presence of PH predicts a poor prognosis. The treatment of PH relies on long-term oxygen therapy. "New" vasodilator drugs have rarely been used in COPD and ILD patients exhibiting severe PH. In advanced ILD the presence of PH is a supplemental argument for considering lung transplantation.

Procoagulant membrane microparticles correlate with the severity of pulmonary arterial hypertension.

RATIONALE: Procoagulant microparticles constitute valuable hallmarks of cell damage. Microparticles also behave as cellular effectors. OBJECTIVES: We hypothesized that the extent of the vascular cell damage measured by circulating microparticles could be related to the severity of pulmonary arterial hypertension (PAH). METHODS: Circulating biomarkers of vascular damage and cell activation were measured in blood samples from 20 patients with PAH. Samples were withdrawn from occluded pulmonary artery and jugular vein. Peripheral venous blood samples were obtained in 23 control subjects. The microparticle procoagulant abilities were quantified by functional prothrombinase and tissue factor assays and their cellular origin was determined. MEASUREMENTS AND MAIN RESULTS: Soluble vascular cellular adhesion molecule-1 and proinflammatory markers, such as monocyte chemoattractant protein-1 and highly specific C-reactive protein, were elevated in patients with PAH compared with control subjects. Microparticles bearing active tissue factor and CD105 (endoglin) were also elevated in patients with PAH compared with control subjects (29 +/- 13 vs. 16 +/- 6 fmol/L, P < 0.001, and 1.10 +/- 0.46 vs. 0.49 +/- 0.33 nmol/L phosphatidylserine equivalent, P < 0.001, respectively). A further increase in endothelium-derived CD105 microparticles was observed in pulmonary arterial blood compared with venous blood in patients with PAH (1.73 +/- 0.77, P = 0.038). Microparticles bearing active tissue factor were at a higher level in patients in functional class III and IV and who were walking fewer than 380 m with the six-minute-walk test. CONCLUSIONS: Circulating markers of endothelium damage, proinflammatory markers, and cell stimulation estimated with circulating microparticles appear to be valuable tools in determining the severity of PAH.