Screening for pulmonary hypertension in systemic sclerosis: the longitudinal development of tricuspid gradient in 227 consecutive patients, 1992-2001

Circulating Plasma microRNAs In Systemic Sclerosis-Associated Pulmonary Arterial Hypertension

Objectives

SSc-associated pulmonary arterial hypertension (SSc-APAH) is a late but devastating complication of SSc. Early identification of SSc-APAH may improve survival. We examined the role of circulating miRNAs in SSc-APAH.

Methods

Using quantitative RT-PCR the abundance of mature miRNAs in plasma was determined in 85 female patients with ACA-positive lcSSc. Twenty-two of the patients had SSc-APAH. Sixty-three SSc controls without PAH were matched for disease duration. Forty-six selected miRNA plasma levels were correlated with clinical data. Longitudinal samples were analysed from 14 SSc-APAH and 27 SSc patients.

Results

The disease duration was 12 years for the SSc-APAH patients and 12.7 years for the SSc controls. Plasma expression levels of 11 miRNAs were lower in patients with SSc-APAH. Four miRNAs displayed higher plasma levels in SSc-APAH patients compared with SSc controls. There was significant difference between groups for miR-20a-5p and miR-203a-3p when correcting for multiple comparisons (P = 0.002 for both). Receiver operating characteristics curve showed AUC = 0.69–0.83 for miR-21-5p and miR-20a-5p or their combination. miR-20a-5p and miR-203a-3p correlated inversely with NT-pro-Brain Natriuretic Protein levels (r = −0.42 and −0.47). Mixed effect model analysis could not identify any miRNAs as predictor of PAH development. However, miR-20a-5p plasma levels were lower in the longitudinal samples of SSc-APAH patients than in the SSc controls.

Conclusions

Our study links expression levels of the circulating plasma miRNAs, especially miR-20a-5p and miR-203a-3p, to the occurrence of SSc-APAH in female patients with ACA-positive lcSSc.

Comparison of the clinical phenotype of systemic sclerosis patients in Iran and France in two university centers

Objectives:

Systemic sclerosis is a severe and rare chronic auto-immune multisystem disorder characterized by vasculopathy and skin stiffness. Ethnic and geographical origin can influence the outcomes. In this study, we compared the phenotypic characteristics of Iranian and French patients.

Methods:

This cross-sectional study was performed on 200 Iranian and 268 French systemic sclerosis patients. Iranian patients collected from the Iranian systemic sclerosis cohort of the Rheumatology Research Center, Shariati hospital, Tehran University of Medical Sciences. The French population was monocentric, and it was constituted by the patients included locally in the EUSTAR database in December 2016.

Results:

The mean age at onset was significantly lower in Iranian patients (35.58 ± 11.68 vs 47.06 ± 13.54, p-value < 0.001). The female-to-male ratio was approximately 5.2:1 and was not different in the two populations. The prevalence of diffuse cutaneous systemic sclerosis was significantly higher in Iranian patients (60.2% vs 42.85%, p-value < 0.001). Calcinosis cutis and joint synovitis were more prevalent in French patients ( p-value = 0.013, <0.001). The positivity of anti-topoisomerase antibody was higher in Iranian patients, whereas the anti-centromere antibody predominated in French cases ( p-value < 0.001). Restrictive pattern of pulmonary function test was more common in Iranian patients ( p-value < 0.001), while estimated pulmonary arterial pressure by echocardiography was higher in French patients ( p-value < 0.001).

Conclusion:

It seems that systemic sclerosis occurred in younger ages among Iranian female with the predominance of diffuse cutaneous subtype. In addition, lung interstitial disease appeared to be more prevalent and severe in Iranians than French patients.

Pulmonary hypertension in Spanish patients with systemic sclerosis. Data from the RESCLE registry

INTRODUCTION

Our objective was to evaluate the pulmonary hypertension (PH) data for Spanish patients with systemic sclerosis (SSc), define the PH types and determine the associated factors.

METHOD

Descriptive study of PH-related data from the multicentre RESCLE registry. Estimated systolic pulmonary artery pressure (esPAP), measured via echocardiogram was considered elevated if ≥ 35 mmHg. Left heart disease (LHD) and interstitial lung disease (ILD) were identified. When performed, data from right heart catheterisation (RHC) were collected.

RESULTS

esPAP was elevated in 350 of 808 patients (43.3%). One hundred and forty-four patients (17.8%) were considered to have PH (88 via RHC and the rest due to elevated esPAP along with evidence of significant LHD or ILD): PAH 3.7%, secondary to ILD 8.3%, secondary to LHD 2.8% and unclassified 3%. Prevalence of elevated esPAP was greater in diffuse SSc (dSSc) than in limited scleroderma (lSSc) (50.5 vs. 42.2%, p 0.046). In the group with elevated esPAP, a lower prevalence of anti-centromere antibodies (41.9% vs. 52.3%, p 0.006) and a greater prevalence of anti-topoisomerase-1 antibodies (ATA) (25.1% vs. 18.6%, p 0.04) were observed compared to the group with normal esPAP. Patients with elevated esPAP had a lower rate of digital ulcers (50.6% vs. 60.2%, p 0.007) and esophageal involvement (83.6% vs. 88.7%, p 0.07) and higher rate of renal crisis (4.6% vs. 1.8%, p 0.066).

CONCLUSIONS

Prevalence of PAH was lower than expected (3.7%). Probability of having elevated esPAP was higher among patients with dSSc and among those with ATA.

Prevalence of auto-antibodies associated to pulmonary arterial hypertension in scleroderma - A review

The prevalence of auto-antibodies associated to pulmonary arterial hypertension in scleroderma patients was reviewed, based on reports cited in two major scientific databases. Data were collected on the following types of antibodies: antinuclear, anti-double-stranded DNA, anticentromere, anti-CENP-A, anti-CENP-B, anti-bicaudal D2, anti-nucleolar, anti-Scl-70 (anti-topoisomerase I), anti-topoisomerase II α, anti-RNP, anti-U1RNP, anti-U3RNP, anti-RNA polymerase III, anti-Th/To, anti-histone, antiphospholipid, anti-PmScl, anti-Sm, anti SSA (anti-Ro),anti SSB (La), anti-Ro52 (TRIM 21), anti-Ku, anti-B23, anti-RuvBL1, anti-RuvBL2, anti-fibrin bound tissue plasminogen activator, anti-endothelial cell, anti-phosphatidylserine-prothrombin complex, anti-endothelin-1 type A receptor, anti-angiotensin II type 1 receptor, anti‑carbonic anhydrase II, anti-fibroblast, anti-cyclic citrullinated peptide, anti-4-sulfated N-Acetyl-lactosamine, class I and II anti-human leukocyte antigen. Auto-antibodies were shown by different authors to be associated to this condition, with different prevalence values for each type of auto-antibody. Antinuclear antibodies, anti-centromere antibodies, antiphospholipid antibodies, anti-U3 RNP antibodies and anti-Th/To antibodies would appear to show a particularly important prevalence in scleroderma patients with pulmonary hypertension, appearing in about 8/10 (antinuclear), 1/ 2 (anti-centromere, anti-phospholipid), and 1/4 (anti-U3RNP, anti-Th/To) of patients. The available evidence points in the direction of a strong association between auto-immune mechanisms and pulmonary hypertension in the setting of scleroderma.

Saudi Guidelines on the Diagnosis and Treatment of Pulmonary Hypertension: Biomarkers in pulmonary arterial hypertension

The biomarker is an indicaror of a biological or pathological process.

Clinical observations, measures or environmental events, or measured laboratory values can all be biomarkers in the appropriate setting. An ideal biomarker reflects the underlying biological process, predicts clinical events, is easily obtainable, is reproducible and is not prohibitively expensive. This typically requires validation in longitudinal cohort studies. Biomarkers may help understand the pathological mechanisms responsible for the disease, help as screening tools, predict disease worsening or decline, and determine adequacy of response to therapeutic interventions.

Updating clinical endpoint definitions

The 6-Minute Walk Distance (6-MWD) has been the most utilized endpoint for judging the efficacy of pulmonary arterial hypertension (PAH) therapy in clinical trials conducted over the past two decades. Despite its simplicity, widespread use in recent trials and overall prognostic value, the 6-MWD has often been criticized over the past several years and pleas from several PAH experts have emerged from the literature to find alternative endpoints that would be more reliable in reflecting the pulmonary vascular resistance as well as cardiac status in PAH and their response to therapy. A meeting of PAH experts and representatives from regulatory agencies and pharmaceutical companies was convened in early 2012 to discuss the validity of current as well as emerging valuable endpoints. The current work represents the proceedings of the conference.

B-type natriuretic peptide in rheumatic diseases: a cardiac biomarker or a sophisticated acute phase reactant?

Natriuretic peptides (NP) are secreted by cardiomyocytes and are reliable markers of cardiac dysfunction and cardiovascular risk by reflecting myocardial stress due to various etiologies. Clinical and occult heart involvement is frequently observed in patients with rheumatic diseases and is associated with increased morbidity and mortality. Cardiac disease in autoimmune disorders encompasses different pathophysiological mechanisms including inflammation and involving either the myocardium or the coronary/pulmonary vessels. Although the major trigger for the synthesis and release of NP is myocardial strain, there is also some support for the concept that inflammation stimulates the neurohormonal system of the heart leading to increased production of NP. Recent studies have focused on the association of NP and inflammation in the context of rheumatic diseases, suggesting that up-regulation of neurohormonal axis in these conditions is linked with inflammation. Additionally the NP have a well-documented role in the diagnostic work-up of patients with connective tissue disease who are at increased risk of developing pulmonary hypertension, as the right ventricular overload results in increased NP synthesis and release. However the precise role of NP in the assessment and the management of cardiovascular risk in patients with rheumatic diseases is yet to be established. In the current article we discuss the pathophysiologic mechanisms involved in enhanced NP expression in patients with rheumatic disorders and their potential clinical implication in daily practice.

Usefulness of serial N-terminal pro-B-type natriuretic peptide measurements for determining prognosis in patients with pulmonary arterial hypertension

Previous studies have shown the prognostic benefit of N-terminal pro-brain natriuretic peptide (NT-pro-BNP) in pulmonary arterial hypertension (PAH) at time of diagnosis. However, there are only limited data on the clinical utility of serial measurements of the inactive peptide NT-pro-BNP in PAH. This study examined the value of serial NT-pro-BNP measurements in predicting prognosis PAH. We retrospectively analyzed all available NT-pro-BNP plasma samples in 198 patients who were diagnosed with World Health Organization group I PAH from January 2002 through January 2009. At time of diagnosis median NT-pro-BNP levels were significantly different between survivors (610 pg/ml, range 6 to 8,714) and nonsurvivors (2,609 pg/ml, range 28 to 9,828, p <0.001). In addition, NT-pro-BNP was significantly associated (p <0.001) with other parameters of disease severity (6-minute walking distance, functional class). Receiver operating curve analysis identified ≥1,256 pg/ml as the optimal NT-pro-BNP cutoff for predicting mortality at time of diagnosis. Serial measurements allowed calculation of baseline NT-pro-BNP (i.e., intercept obtained by back-extrapolation of concentration-time graph), providing a better discrimination between survivors and nonsurvivors than NT-pro-BNP at time of diagnosis alone (p = 0.010). Furthermore, a decrease of NT-pro-BNP of >15%/year was associated with survival. In conclusion, a serum NT-pro-BNP level ≥1,256 pg/ml at time of diagnosis identifies poor outcome in patients with PAH. In addition, a decrease in NT-pro-BNP of >15%/year is associated with survival in PAH.

Pulmonary arterial hypertension associated with systemic sclerosis in the Czech Republic

BACKGROUND

Systemic sclerosis (SSc) is an important cause of pulmonary arterial hypertension (PAH), with an estimated prevalence of 7.85-26.7%.

OBJECTIVE

Our aim was to estimate the prevalence of PAH among patients with SSc in the Czech Republic and to compare haemodynamics in SSc patients diagnosed with PAH through screening with those diagnosed previously, based on symptoms.

METHODS

During 2007, SSc patients in the Czech Republic, without significant pulmonary function impairment or cardiac disease, underwent screening for PAH with transthoracic echocardiography. Those with a tricuspid regurgitant (TR) jet gradient suggestive of PAH (>30 mmHg) underwent subsequent right heart catheterisation (RHC) to confirm the diagnosis (mean pulmonary arterial pressure, mPAP, ≥25 mmHg; pulmonary capillary wedge pressure, ≤15 mmHg). Haemodynamics in patients diagnosed with PAH in this way were compared with those in patients diagnosed previously, based on symptoms.

RESULTS

Two hundred and three SSc patients (mean age, 53.8 ± 13 years; 82.3% women) from 26 rheumatology practices were screened. Among these, 17 had a TR jet gradient >30 mmHg and underwent RHC; PAH was confirmed in six patients. These six patients were found to have significantly lower mPAP than nine patients diagnosed previously with PAH, based on symptoms (31.17 ± 5.56 vs. 46.89 ± 9.48 mmHg, p = 0.0014).

CONCLUSION

Prevalence of PAH in our SSc cohort was 7.08%. SSc patients diagnosed with PAH through screening have less advanced disease in terms of haemodynamics than those with PAH diagnosed previously based on symptoms; their prognosis is therefore likely to be more favourable.

The current state of biomarkers in systemic sclerosis

Scleroderma is a complex, multisystem autoimmune rheumatic disease with wide heterogeneity in phenotype and outcome. There are often coexisting ongoing pathologic processes including immune system activation, progressive fibrosis, and vascular disease in subsets of patients. Currently, it is challenging to identify patients at risk for developing adverse outcomes and to determine which patients are responding to current therapies. For these reasons, it is highly valuable to find easily measurable biomarkers that may represent ongoing disease activity or treatment response. This review examines the current state of biomarker development in systemic sclerosis and identifies areas in which further work should be directed.

Comparison of brain natriuretic peptide (BNP) and NT-proBNP in screening for pulmonary arterial hypertension in patients with systemic sclerosis

OBJECTIVE

To compare the performance of brain natriuretic peptide (BNP) and N-terminal pro-brain natriuretic peptide (NT-proBNP) in screening for pulmonary arterial hypertension (PAH) in systemic sclerosis (SSc).

METHODS

Between January 2008 and March 2009, outpatients referred to our unit and satisfying LeRoy criteria for SSc were assessed for PAH. Doppler echocardiography, BNP measurement, and NT-proBNP measurement were done concomitantly for a complete clinical, instrumental, and biochemical evaluation. Right-heart catheterization was carried out in cases of suspected PAH [estimated pulmonary arterial pressure (PAP) ≥ 36 mm Hg; diffusion capacity for carbon monoxide (DLCO) ≤ 50% of predicted value; 1-year DLCO decline ≥ 20% in absence of pulmonary fibrosis; unexplained dyspnea].

RESULTS

One hundred thirty-five patients were enrolled (124 women, 11 men; 96 limited SSc, 39 diffuse SSc); precapillary PAH was found in 20 patients (15 limited SSc, 5 diffuse SSc). The estimated PAP correlated with both BNP (R = 0.3; 95% CI 0.14-0.44) and NT-proBNP (R = 0.3, 95% CI 0.14-0.45). BNP [area under the curve (AUC) 0.74, 95% CI 0.59-0.89] was slightly superior to NT-proBNP (AUC 0.63, 95% CI 0.46-0.80) in identification of PAH, with diagnosis cutoff values of 64 pg/ml (sensitivity 60%, specificity 87%) and 239.4 pg/ml (sensitivity 45%, specificity 90%), respectively. BNP (log-transformed, p = 0.032) and creatinine (p = 0.049) were independent predictors of PAH, while NT-proBNP was not (p = 0.50).

CONCLUSION

In our single-center study, the performance of BNP was slightly superior to that of NT-proBNP in PAH screening of patients with SSc, although normal levels of these markers do not exclude diagnosis. We observed that impaired renal function is associated with an increased risk of PAH in SSc. Further multicenter studies are needed to confirm our results (ClinicalTrials.gov ID NCT00617487).

Variable prevalence of pulmonary hypertension in patients with advanced interstitial pneumonia

BACKGROUND

Pulmonary hypertension may occur in patients with interstitial pneumonia and is associated with increased mortality. We sought to determine the prevalence of pulmonary hypertension in sub-groups of patients with interstitial pneumonia and to investigate possible associations between pulmonary vascular hemodynamics and pulmonary function.

METHODS

The presence or absence of pulmonary hypertension was assessed in 70 patients with advanced interstitial pneumonia who underwent right heart catheterization. The associations of pulmonary hypertension with clinical characteristics and pulmonary function tests were analyzed.

RESULTS

The prevalence of pulmonary hypertension in patients with idiopathic interstitial pneumonia was 29% vs 64% in patients with connective tissue disease-interstitial pneumonia (p = 0.013). African American patients had a significantly higher prevalence of pulmonary hypertension in the entire study population (81% vs 22%, p < 0.001) and in the idiopathic interstitial pneumonia group (70% vs 19%, p < 0.01). Regression analyses revealed no association between mean pulmonary artery pressure (mPAP) and forced vital capacity or mPAP and diffusion capacity of the lung for carbon monoxide in the entire cohort or in sub-groups of patients.

CONCLUSIONS

African American patients and patients with connective tissue disease-interstitial pneumonia had a high prevalence of pulmonary hypertension. Non-African American patients with advanced idiopathic interstitial pneumonia (including idiopathic pulmonary fibrosis) had a low prevalence of pulmonary hypertension.

Echocardiography as an Outcome Measure in Scleroderma-related Pulmonary Arterial Hypertension: A Systematic Literature Analysis by the EPOSS Group

Objective.

To assess the validation status of echocardiography with continuous Doppler (echo-Doppler) as an outcome measure in pulmonary arterial hypertension associated with systemic sclerosis (PAH-SSc).

Methods.

Structured literature review on full-text English articles was performed using the PubMed and Cochrane databases. Assessment of validation of echo-Doppler was based on the OMERACT filter criteria with the domains truth (face, content, construct, and criterion validity), discrimination, and feasibility.

Results.

Out of 35 studies eligible for analysis, only 5 included well defined PAH-SSc subgroups (World Health Organization criteria). Echo was considered as having face validity based on expert opinion and high number of studies using echo for evaluation of patients with SSc. Echo was considered partially validated with respect to criterion validity based on significant correlations between echo measures and right-heart catheterization in patients with SSc at risk of PAH/PH. However, echo was found to lack specificity (lack of content validity), since measurements of echo pulmonary pressure may be influenced by left-heart disease and interstitial lung disease. Data from general populations of patients with scleroderma indicate that evaluation of pulmonary artery pressure by echo might not be available in all PAH-SSc patients because of technical factors. No studies enabling evaluation of the discriminant capacity over time and treatment of echo in PAH-SSc could be identified.

Conclusion.

Further studies are needed to fully validate echo-Doppler as an outcome measure in PAH-SSc. These studies would include cross-sectional analysis of baseline measures and longitudinal data of placebo and verum groups in randomized controlled trials of patients with PAH-SSc.

Biomarkers of vascular disease in scleroderma

Vascular disease is present in every patient with scleroderma and is a major source of morbidity and mortality. There is a subset of patients who will develop severe and sometimes life-threatening vascular events. We have good evidence that an insult to the microvasculature occurs early in the disease course, but there is a subset of patients who have an ongoing chronic process, the end result of which are events such as digital loss and pulmonary arterial hypertension. The ability to detect this process at an early stage by simple means would be of great value as our ability to treat these vascular complications improves with time. We have a significant amount of evidence of vascular perturbation from studies of peripheral blood in scleroderma, but know very little about the ability of these biomarkers to predict vascular outcomes. In this review, we will critically assess our current knowledge of the use of biomarkers of vascular disease in scleroderma and the possible directions of future research in this area.

Systemic sclerosis: a world wide global analysis

The objective of this study was to analyze epidemiological tendencies of systemic sclerosis (SSc) around the world in order to identify possible local variations in the presentation and occurrence of the disease. A systematic review of the literature was performed through electronic databases using the keywords "Systemic Sclerosis" and "Clinical Characteristics." Out of a total of 167 articles, 41 were included in the analysis. Significant differences in the mean age at the time of diagnosis, subsets of SSc, clinical characteristics, and presence of antibodies were found between different regions of the word. Because variations in both additive and nonadditive genetic factors and the environmental variance are specific to the investigated population, ethnicity and geography are important characteristics to be considered in the study of SSc and other autoimmune diseases.

Echocardiographic and right heart catheterization techniques in patients with pulmonary arterial hypertension

BACKGROUND

The cardiovascular assessment of patients with suspected pulmonary arterial hypertension (PAH) involves Doppler echocardiography and often subsequent confirmation by right heart catheterization (RHC). However, there appears to be limited consensus on the appropriate technique(s) for assessing PAH, and thus no clear, comprehensive guidelines exist for assessment of PAH. The aim of this paper is to review the Doppler echocardiographic and RHC techniques for the diagnosis and/or assessment of PAH.

METHOD

We searched Medline (1966 to August 2006) and EMBASE (1980 to August 2006) bibliographic databases to allow identification of all potentially relevant studies and review articles. In addition, the reference lists of included articles were scanned to identify relevant references and unpublished reports missed by the search strategy.

RESULTS

Our findings show that recommendations for the echocardiographic assessment of PAH at rest or with exercise are heterogeneous. Clinical practice guidelines provide limited details. Although more specific information regarding echocardiographic techniques can be obtained from individual research articles, the techniques employed and the methods used to calculate specific hemodynamic variables do not appear to be consistent throughout the literature. RHC techniques for the confirmation of PAH are more consistent, albeit less frequently reported. The literature search identified several articles where indications and considerations for the catheterization of patients with PAH are discussed, together with safety considerations and principles for the accurate assessment of hemodynamic variables.

CONCLUSION

Although clinical practice guidelines and numerous research studies provide details of echocardiographic measures in patients with PAH, greater consensus and standardisation of measurement techniques is required. A minimum dataset for the evaluation of PAH by these techniques is suggested.

The clinical significance of serum N-terminal pro-brain natriuretic peptide in systemic sclerosis patients

We evaluated the clinical significance of serum N-terminal pro-brain natriuretic peptide (NT-proBNP) level in systemic sclerosis (SSc). We studied 45 SSc patients (30 with limited and 15 with diffuse cutaneous SSc) of mean age +/- SD 47.1 +/- 12.9 years, mean duration of disease 10.2 +/- 6.0 years, and 45 age- and sex-matched healthy controls. Pulmonary artery pressure was measured by echocardiography. Lung involvement was evaluated by pulmonary function testing and by using high-resolution computed tomography scores. Serum NT-proBNP levels were measured using a sandwich electrochemiluminescent immunoassay. Serum NT-proBNP levels were significantly higher in patients with SSc compared to healthy controls. When the patients were divided into clinical subsets, serum NT-proBNP was higher in diffuse SSc than in limited SSc. Serum NT-proBNP levels were found to be positively correlated with age, skin thickness score, and systolic pulmonary artery pressure and negatively correlated with percentage of carbon monoxide diffusion capacity (DLco). Multivariate analysis showed that serum NT-proBNP levels were positively correlated with age (p = 0.010), skin thickness score (p = 0.000), and blood pressure (p = 0.021) and negatively correlated with %DLco (p = 0.016). Fifty-seven percent of the variation in log (proBNP) can be explained by the multivariate model (R (2) = 0.57). Serum NT-proBNP levels were higher in SSc patients (particularly the diffuse subset) than in healthy controls and were found to be correlated with skin thickness and %DLco. We conclude that serum NT-proBNP may be a biologic marker of skin fibrosis and pulmonary vascular involvement in SSc.

NT-proBNP in chronic hypercapnic respiratory failure: A marker of disease severity, treatment effect and prognosis

BACKGROUND

Natriuretic peptides are considered as reliable indicators of left-heart failure (HF) and are useful for differential diagnosis of dyspnoea.

AIM

We evaluated the clinical significance of N-terminal pro-brain natriuretic peptide (NT-proBNP) in patients with chronic hypercapnic respiratory failure (CHRF).

METHODS

In 60 patients with CHRF, plasma concentrations of NT-proBNP were assessed at baseline and after treatment including non-invasive ventilation (NIV). The relationship of NT-proBNP to disease severity and its predictive value for survival were evaluated up to 4 years.

RESULTS

NT-proBNP levels were markedly elevated in patients with CHRF (n=60; geometric mean (SD) 546.4 (4.9) pg/mL; p<0.001) compared to healthy controls (n=182; 49.0 (2.2) pg/mL). After excluding patients with concomitant HF or renal impairment, levels were still increased (n=43; 393.2 (3.8) pg/mL; p<0.001). According to multivariate regression, hypoxia and exacerbation independently determined NT-proBNP levels (p<0.05 each). After initiation of NIV, blood gases and lung function improved and NT-proBNP decreased (-31.3 (0.3)%; p<0.001). During 22.5 (2.2) months follow-up, NT-proBNP was not significantly associated with survival in the total population, however, the subgroup of patients with levels >722 pg/mL (67th percentile) and no adherence to NIV displayed poor prognosis (hazard ratio=0.21; 95%-CI=0.022-0.580; p=0.0091).

CONCLUSIONS

NT-proBNP was highly elevated in patients with CHRF and correlated with the degree of respiratory impairment and exacerbation. Correspondingly, treatment including NIV led to reduction of NT-proBNP. These data indicate a potential role of NT-proBNP in assessing disease severity, treatment efficacy and prognosis in CHRF.

Determinants of Pulmonary Arterial Hypertension in Scleroderma

OBJECTIVE

To define risk factors associated with pulmonary arterial hypertension (PAH) in a large cohort of patients with systemic sclerosis (SSc).

METHODS

SSc patients undergoing screening for PAH by means of Doppler echocardiography were identified and their charts were retrospectively reviewed. In all patients, we recorded systolic pulmonary artery pressure along with pulmonary function testing, clinical, and laboratory data. PAH was defined as right ventricular systolic pressure equal or greater than 40 mm Hg.

RESULTS

Of 114 SSc patients with echocardiographic measurements, PAH was found in 33 (29%) patients. In a multiple logistic regression analysis, the presence of pulmonary fibrosis on thoracic computed tomography (OR 6.78, CI 1.54 to 29.9), forced vital capacity less than 80% predicted (OR 3.03, CI 1.1 to 8.35), and duration of Raynaud's phenomenon preceding the onset of skin changes for at least 3 years (OR 5.75, CI 1.9 to 17.41) were found to be independent predictors of PAH. Age, disease duration, disease subtype, or autoantibodies were not associated with PAH in our patients.

CONCLUSIONS

The present analysis identified pulmonary fibrosis and Raynaud's phenomenon preceding SSc skin manifestations by at least 3 years as risk factors for PAH in our scleroderma cohort. Screening for PAH in these high-risk patients may detect PAH at an earlier stage and guide decisions on therapeutic interventions.

Pulmonary hypertension in patients with interstitial lung diseases

Pulmonary hypertension (PH) in patients with interstitial lung diseases (ILDs) is not well recognized and can occur in the absence of advanced pulmonary dysfunction or hypoxemia. To address this topic, we identified relevant studies in the English language by searching the MEDLINE database (1966 to November 2006) and by individually reviewing the references of identified articles. Connective tissue disease-related ILD, sarcoidosis, idiopathic pulmonary fibrosis, and pulmonary Langerhans cell histiocytosis are the ILDs most commonly associated with PH. Pulmonary hypertension is an underrecognized complication in patients with ILDs and can adversely affect symptoms, functional capacity, and survival. Pulmonary hypertension can arise in patients with ILDs through various mechanisms, Including pulmonary vasoconstriction and vascular remodeling, vascular destruction associated with progressive parenchymal fibrosis, vascular inflammation, perivascular fibrosis, and thrombotic angiopathy. Diagnosis of PH in these patients requires a high index of suspicion because the clinical presentation tends to be nonspecific, particularly in the presence of an underlying parenchymal lung disease. Doppler echocardiography is an essential tool in the evaluation of suspected PH and allows ready recognition of cardiac causes. Right heart catheterization is needed to confirm the presence of PH, assess its severity, and guide therapy. Management of PH in patients with ILDs is guided by identification of the underlying mechanism and the clinical context. An increasing number of available pharmacologic agents in the treatment of PH allow possible treatment of PH in some patients with ILDs. Whether specific treatment of PH in these patients favorably alters functional capacity or outcome needs to be determined.

N-terminal Pro-Brain Natriuretic Peptide and Renal Insufficiency as Predictors of Mortality in Pulmonary Hypertension

BACKGROUND

N-terminal pro-brain natriuretic peptide (NT-proBNP) is a byproduct of the brain natriuretic peptide (BNP) that was shown to be of prognostic value in pulmonary hypertension (PH). The role of NT-proBNP in PH has to be determined, especially under the influence of renal impairment that might lead to an accumulation of the peptide, and may be a sign of increased mortality per se.

METHODS

We assessed NT-proBNP, BNP, renal function, and hemodynamic parameters (during right-heart catheterization) in 118 consecutive patients with isolated PH, excluding left-heart disease. Depending on the calculated creatinine clearance, patients were classified into different groups of renal function. Correlation analysis was performed on all key parameters. Results were then compared between the levels of renal function. The prognostic value of each parameter was assessed during a mean follow-up period of 10 months.

RESULTS

Twenty-two patients (approximately 19%) had significantly impaired renal function (creatinine clearance < 60 mL/min). Although the overall levels of NT-proBNP were correlated with hemodynamics, we observed no correlation in the group with significant renal dysfunction. Moreover, NT-proBNP was related to creatinine clearance. Finally, NT-proBNP and renal insufficiency were independent predictors of death during univariate and multivariate analysis, whereas BNP only predicted mortality in univariate analysis.

CONCLUSIONS

The diagnostic accuracy of NT-proBNP as a parameter of the hemodynamic status is diminished by renal function. However, NT-proBNP could be superior to BNP as a survival parameter in PH because it integrates hemodynamic impairment and renal insufficiency, which serves as a sign of increased mortality per se.

Scleroderma Lung

The lungs are frequently involved in systemic sclerosis ('scleroderma'), a rare, disabling disease of unknown origin, characterised by skin thickening and Raynaud's phenomenon. The pathogenesis of scleroderma is complex, but signs and symptoms of excessive fibrosis, vasculopathy and inflammation are almost universally present. Dyspnoea in scleroderma patients can be due to chest wall tightening from skin thickening, pleural disease, cardiac involvement, myositis of intercostal muscles, or so-called scleroderma lung disease. Scleroderma lung disease encompasses vascular (pulmonary artery hypertension) or interstitial lung disease, or both. A comprehensive work-up is required to delineate the underlying cause of dyspnoea in a scleroderma patient, and to establish the contribution of each component to the symptoms. This should include a 6-minute walk test, pulmonary function testing, high-resolution thoracic CT scanning, ECG, echocardiography and, if pulmonary artery hypertension is suspected, right-heart catheterisation; bronchoalveolar lavage is optional. Lung disease in scleroderma contributes significantly to excess morbidity and early mortality, especially when diffusion capacity drops below 40% and/or forced vital capacity below 50%. However, recent clinical studies have unequivocally demonstrated that scleroderma lung disease is amenable to treatment with new vasodilatory drugs that target specific pathways involved in vasoconstriction, or with cyclophosphamide for interstitial lung disease. Uncontrolled studies have suggested that these therapies also have an impact on survival, but controlled studies with a long follow-up are needed to corroborate this point.

Atteinte cardiaque de la sclérodermie systémique

Primary myocardial involvement is common in systemic sclerosis. Increasing evidence strongly suggests that this involvement is related to repeated focal ischemic injury causing irreversible myocardial fibrosis. The underlying mechanism appears to be microcirculatory impairment with abnormal vasoreactivity, with or without structural vascular abnormalities. Clinically evident cardiac involvement is recognized to be a poor prognostic factor. Pericardial involvement is frequent but usually asymptomatic. Conduction system abnormalities appear common but not serious, while arrhythmias may be life-threatening. No significant valvular involvement appears to be associated with systemic sclerosis. Treatment for myocardial involvement includes long-term systematic administration of calcium channel blockers and possibly angiotensin-converting enzyme inhibitors, frequently given at high dosage.

Microvascular damage in systemic sclerosis: Detection and monitoring with biomarkers

Vascular disease is universal in patients with systemic sclerosis (SSc), but there is a wide variability in its severity. It is clear that there is an early insult to the microvasculature, followed-up by on-going chronic process. This results in profound vascular damage in a subset of patients who develop severe events such as digital loss and pulmonary arterial hypertension. Although there is abundant evidence of vascular perturbation from studies of peripheral blood in SSc, there are few data about the ability to use these biomarkers to predict vascular outcomes. This paper examines the possibility of using circulating biomarkers to assess vascular disease activity and to predict severe vascular events among patients with SSc.

New developments in scleroderma interstitial lung disease

PURPOSE OF REVIEW

To review the recent medical literature pertaining to interstitial lung disease found in association with systemic sclerosis remains a major contributor to morbidity and mortality. Significant progress is being made in terms of understanding the pathogenesis, the best approaches to clinical evaluation, and various options for therapy of systemic sclerosis patients whose disease course is complicated by interstitial lung disease.

RECENT FINDINGS

Recent studies highlight the importance of microvascular disease, autoimmunity, and fibroblast differentiation/activation in the pathogenesis of systemic sclerosis-interstitial lung disease, particularly in the early phase of disease. It appears as if the balance between various pro-fibrotic/pro-inflammatory and anti-fibrotic/anti-inflammatory mediators may be central to interstitial lung disease pathogenesis, which presents potential opportunities for therapeutic intervention. The clinical approach to staging of disease activity remains controversial. High resolution computed tomography scans, bronchoalveolar lavage and various serum markers (e.g., surfactant protein D and KL-6) each may provide useful information about the degree of activity of the systemic sclerosis-interstitial lung disease. Currently, treatment recommendations are limited by a scarcity of well designed clinical trials, but the recently completed Scleroderma Lung Study is a model for future studies and is providing useful information about this important complication of systemic sclerosis.

SUMMARY

Basic and clinical studies of systemic sclerosis patients with interstitial lung disease are yielding promising data that ultimately will be translated in to more effective diagnostic and therapeutic strategies.

Autoimmunity and interstitial lung disease

PURPOSE OF REVIEW

The pathogenesis of idiopathic pulmonary fibrosis as well as that of several other interstitial lung diseases is poorly understood. The role of autoimmunity in interstitial lung diseases associated with connective tissue disorders such as systemic sclerosis, systemic lupus erythematosus, and rheumatoid arthritis as well as the vasculitides is well established. There is at least some evidence in the literature that supports the role of autoimmunity as one of the mechanisms of alveolar injury responsible for idiopathic pulmonary fibrosis. This review is an attempt to summarize the studies on this subject.

RECENT FINDINGS

Repeated extraneous insults and exposures are considered to be responsible for recurrent alveolar injury, inflammation, dysregulated tissue repair, and fibroproliferation resulting in pulmonary fibrosis. The presence of autoantibodies in the sera of patients with idiopathic pulmonary fibrosis has been demonstrated in a few studies. Several autoantibodies, including anti-Sm antibodies, antibodies to U1 ribonucleoproteins, and antibodies to U3 ribonucleoproteins, have been demonstrated in connective tissue disorders, many of which are associated with interstitial lung involvement. Autoimmunity has been also suggested as a possible mechanism of rejection caused by bronchiolitis obliterans after lung transplantation.

SUMMARY

It might seem that the role of autoimmunity in interstitial lung disease has been underestimated or even underinvestigated. The subject requires further investigation, especially with regard to the problems of lung allograft rejection due to bronchiolitis obliterans of nonalloimmunity origin and the failure of patients with idiopathic pulmonary fibrosis to respond to most forms of currently available therapy.

B-type natriuretic peptide: Issues for the intensivist and pulmonologist

OBJECTIVE

B-type natriuretic peptide (BNP) and N-terminal pro-BNP (NT-proBNP), although promising as biomarkers for heart failure, are affected by multiple confounders. The purpose of this article is to review the literature on the utility of BNP and NT-proBNP as biomarkers, with a focus on their role in critical illness and pulmonary diseases.

DATA SOURCE

Published articles on BNP and NT-proBNP.

DATA ANALYSIS

Multiple disorders in the intensive care unit cause elevated BNP and NT-proBNP levels, including cardiac diseases, shock, pulmonary hypertension, acute respiratory distress syndrome, acute pulmonary embolism, chronic obstructive pulmonary disease, renal failure, and other conditions.

CONCLUSIONS

Intensivists and pulmonologists should understand that BNP and NT-proBNP levels might be raised to different degrees not only in heart failure but also in critical illness and various pulmonary diseases; in these situations, BNP and NT-proBNP may also serve as markers of severity and prognosis.