Determinants of exercise-induced pulmonary arterial hypertension in systemic sclerosis

Clinical course of COPD patients with exercise-induced elevation of pulmonary artery pressure or less severe pulmonary hypertension presenting with respiratory symptoms and the impact of bosentan intervention-prospective, single-center, randomized, parallel-group study

BACKGROUND

The data on bosentan were lacking for the treatment of exercise-induced elevation of pulmonary artery pressure (eePAP) or less severe PH in COPD. This study was conducted to investigate long-term efficacy and safety of bosentan for the treatment of eePAP or less severe PH in COPD.

METHODS

COPD patients diagnosed at this hospital as having COPD (WHO functional class II, III or IV) with eePAP or less severe PH whose respiratory symptoms were stable but remained and gradually progressed even after COPD therapy were randomly assigned in a 1:1 ratio to receive either bosentan or no PH treatment for two years and assessed at baseline and every 6 months for respiratory failure, activities of daily living (ADL), lung and heart functions by right heart catheterization (RHC), and other parameters.

RESULTS

A total of 29 patients who underwent RHC for detail examination were enrolled in the current study between August 2010 and October 2018.No death occurred in drug-treated group (n = 14) for 2 years; 5 patients died in untreated group (n = 15). Significant differences were noted between the 2 group in hospital-free survival (686.00 ± 55.87 days vs. 499.94 ± 53.27 days; hazard ratio [HR], 0.18; P = 0.026) and overall survival (727 days vs. 516.36 ± 55.38 days; HR, 0.095; P = 0.030) in all causes of death analysis, but not in overall survival in analysis of respiratory-related death. Bosentan was not associated with increased adverse events including requiring O2 inhalation.

CONCLUSIONS

This study suggested that the prognosis for COPD patients with eePAP or less severe PH presenting with respiratory symptoms was very poor and that bosentan tended to improve their prognosis and suppress ADL deterioration without worsening respiratory failure.

TRIAL REGISTRATION

This study was registered with UMIN-CTR Clinical Trial as UMIN000004749 . First trial registration at 18/12/2010.

Exercise-Induced Pulmonary Hypertension: A Valid Entity or Another Factor of Confusion?

Exercise-induced pulmonary hypertension EIPH has been defined as an increase in mean pulmonary arterial pressure (mPAP) during exercise in otherwise normal values at rest. EIPH reflects heart and/or lung dysfunction and may precede the development of manifest pulmonary hypertension (PH) in a proportion of patients. It is also associated with decreased life expectancy in patients with heart failure with reduced ejection fraction (HFrEF) or left ventricle (LV) valvular diseases. Diastolic dysfunction exacerbated during exercise relates to increased LV filling pressure and left atrial pressure (LAP). In this context backward, transmitted pressure alone or accompanied with backward blood flow promotes EIPH. The gold standard of EIPH assessment remains the right heart catheterization during exercise, which is an accurate but invasive method. Alternatively, non-invasive diagnostic modalities include exercise stress echocardiography (ESE) and cardiopulmonary exercise testing (CPET). Both diagnostic tests are performed under gradually increasing physical stress using treadmill and ergo-cycling protocols. Escalating workload during the exercise is analogous to the physiological response to real exercise. The results of the latter techniques show good correlation with invasive measurements, but they suffer from lack of validation and cut-off value determination. Although it is not officially recommended, there are accumulated data supporting the importance of EIPH diagnosis in the assessment of other mild/subclinical or probably fatal diseases in patients with latent PH or heart failure or LV valvular disease, respectively. Nevertheless, larger, prospective studies are required to ensure its role in clinical practice.

Clinical application of pulmonary vascular resistance in patients with pulmonary arterial hypertension

Pulmonary arterial hypertension is a type of malignant pulmonary vascular disease, which is mainly caused by the increase of pulmonary vascular resistance due to the pathological changes of the pulmonary arteriole itself, which eventually leads to right heart failure and death. As one of the diagnostic indicators of hemodynamics, pulmonary vascular resistance plays an irreplaceable role in the pathophysiology, diagnosis and treatment of pulmonary arterial hypertension. It provides more references for the evaluation of pulmonary arterial hypertension patients. This article summarizes the clinical application of pulmonary vascular resistance in patients with pulmonary arterial hypertension.

The Role of Exercise Doppler Echocardiography to Unmask Pulmonary Arterial Hypertension in Selected Patients with Systemic Sclerosis and Equivocal Baseline Echocardiographic Values for Pulmonary Hypertension

Recently, a lower mean pulmonary arterial pressure (PAP) cutoff of >20 mmHg for pulmonary hypertension (PH) definition has been proposed. We examined whether exercise Doppler echocardiography (EDE) can unmask PA hypertension (PAH) in systemic sclerosis (SSc) patients whose baseline echocardiography for PH is equivocal. We enrolled 49 patients with SSc who underwent treadmill EDE. Tricuspid regurgitation (TR) velocity was recorded immediately after EDE. Inotropic reserve of right ventricle (RV) was assessed by the change (post-prior to exercise) of tissue Doppler imaging-derived peak systolic velocity (S) of tricuspid annulus. Inclusion criteria comprised preserved left and RV function, and baseline TR velocity between 2.7 and 3.2 m/s. All patients had right-heart catheterization (RHC) within 48 h after EDE. From 46 patients with good quality of post-exercise TR velocity, RHC confirmed PAH in 21 (45.6%). Post-exercise TR velocity >3.4 m/s had a sensitivity of 90.5%, a specificity of 80% and an accuracy of 84.8% in detecting PAH. Inotropic reserve of RV was positively correlated with maximum achieved workload in METs (r = 0.571, p < 0.001). EDE has a good diagnostic accuracy for the identification of PAH in selected SSc patients whose baseline echocardiographic measurements for PH lie in the gray zone, and it is also potentially useful in assessing RV contractile reserve.

Feasibility of semi-recumbent bicycle exercise Doppler echocardiography for the evaluation of the right heart and pulmonary circulation unit in different clinical conditions: the RIGHT heart international NETwork (RIGHT-NET)

Exercise Doppler echocardiography (EDE) is a well-validated tool in ischemic and valvular heart diseases. However, its use in the assessment of the right heart and pulmonary circulation unit (RH-PCU) is limited. The aim of this study is to assess the semi-recumbent bicycle EDE feasibility for the evaluation of RH-PCU in a large multi-center population, from healthy individuals and elite athletes to patients with overt or at risk of developing pulmonary hypertension (PH). From January 2019 to July 2019, 954 subjects [mean age 54.2 ± 16.4 years, range 16-96, 430 women] underwent standardized semi-recumbent bicycle EDE with an incremental workload of 25 watts every 2 min, were prospectively enrolled among 7 centers participating to the RIGHT Heart International NETwork (RIGHT-NET). EDE parameters of right heart structure, function and pressures were obtained according to current recommendations. Right ventricular (RV) function at peak exercise was feasible in 903/940 (96%) by tricuspid annular plane systolic excursion (TAPSE), 667/751 (89%) by tissue Doppler-derived tricuspid lateral annular systolic velocity (S') and 445/672 (66.2%) by right ventricular fractional area change (RVFAC). RV-right atrial pressure gradient [RV-RA gradient = 4 × tricuspid regurgitation velocity² (TRV)] was feasible in 894/954 patients (93.7%) at rest and in 816/954 (85.5%) at peak exercise. The feasibility rate in estimating pulmonary artery pressure improved to more than 95%, if both TRV and/or right ventricular outflow tract acceleration time (RVOT AcT) were considered. In high specialized echocardiography laboratories semi-recumbent bicycle EDE is a feasible tool for the assessment of the RH-PCU pressure and function.

Significant Clinical Indexes of Exercise-Induced Pulmonary Hypertension in Patients With Connective Tissue Disease

Background: Pulmonary hypertension (PH) is an important cause of morbidity in patients with connective tissue disease (CTD), and an early stage of PH could present as exercise-induced PH (EIPH). This study investigated the significant clinical indexes of EIPH in patients with CTD.

Methods and Results: We enrolled 63 patients with CTD who did not have PH at rest. All patients underwent the 6-min walk test (6MWT), and systolic pulmonary artery pressure (SPAP) was evaluated on echocardiography before and after 6MWT. EIPH was defined as SPAP ≥40 mmHg after 6 WMT. Thirty-five patients had EIPH. On univariate logistic analysis, SPAP at rest, log brain natriuretic peptide (BNP), vital capacity (VC), and forced expiratory volume in 1 s (FEV1.0) were significantly correlated with EIPH. On multiple logistic analysis, SPAP at rest and VC were independent predictors of EIPH, whereas FEV1.0 and log BNP were not significantly associated with EIPH. The area under the receiver operating characteristics curve between EIPH and BNP, SPAP at rest, VC or FEV1.0 was 0.67, 0.76, 0.74, and 0.75, respectively.

Conclusions: SPAP at rest and respiratory function, especially VC, could be independent predictors of EIPH in patients with CTD.

Visfatin and chemerin levels correspond with inflammation and might reflect the bridge between metabolism, inflammation and fibrosis in patients with systemic sclerosis

Introduction

Adipokines are regulatory molecules which act as mediators of the inflammatory, fibrotic and metabolic processes by interacting with the immune system.

Aim

We hypothesized that chemerin and visfatin by pro-inflammatory properties play a significant role in inflammation in systemic sclerosis. To address this hypothesis, we determined serum chemerin and visfatin levels in SSc patients, compared with the control group and defined the correlations with clinical and laboratory parameters in SSc patients.

Material and methods

The study included 48 Caucasian female patients with SSc and 38 healthy subjects of the control group. Serum concentrations of selected adipokines were measured using commercially available ELISA Kits.

Results

Patients with SSc had higher chemerin levels (209.38 ±55.35 ng/ml) than the control group (182.71 ±33.94 ng/ml) and the difference was statistically significant (Z = 2.14, p = 0.032). The highest chemerin levels were found in dcSSc patients (242.46 ±95.82 ng/ml). We indicated a positive correlation of chemerin and visfatin with levels of inflammatory markers: CRP (r = 0.35, p = 0.013 for chemerin; r = 0.41, p = 0.003 for visfatin) and ESR (r = 0.31, p = 0.03 for chemerin; r = 0.30, p = 0.03 for visfatin). What is more, chemerin manifested a statistically significant positive correlation with the concentration of complement component C3 (r = 0.47, p = 0.001) and C4 (r = 0.29, p = 0.049), whereas visfatin correlated with C4 levels (r = 0.32, p = 0.029).

Conclusions

The results of our study indicate that chemerin and visfatin as pro-inflammatory cytokines might represent new markers corresponding with inflammation in systemic sclerosis and might reflect the bridge between metabolism, inflammation and potentially, chemerin may also link inflammation with skin and lung fibrosis.

A review of exercise pulmonary hypertension in systemic sclerosis

In general, pulmonary vascular disease has important negative prognostic implications, regardless of the associated condition or underlying mechanism. In this regard, systemic sclerosis is of particular interest as it is the most common connective tissue disease associated with pulmonary hypertension, and a well-recognized at-risk population. In the setting of systemic sclerosis and unexplained dyspnea, the concept of using exercise to probe for underlying pulmonary vascular disease has acquired significant interest. In theory, a diagnosis of systemic sclerosis-associated exercise pulmonary hypertension may allow for earlier therapeutic intervention and a favorable alteration in the natural history of the pulmonary vascular disease. In the context of underlying systemic sclerosis, the purpose of this article is to provide a comprehensive review of the evolving definition of exercise pulmonary hypertension, the current role and methodologies for non-invasive and invasive exercise testing, and the importance of the right ventricle.

Clinical associations of serum leptin and leptin/adiponectin ratio in systemic sclerosis

INTRODUCTION

Leptin and adiponectin have recently received the attention of researchers as attractive biomarkers in systemic sclerosis (SSc) because of their role in the inflammatory process, vascular function and fibrosis. We hypothesized that leptin and adiponectin may be associated with disease activity and severity in patients with SSc.

AIM

To compare serum leptin, adiponectin and leptin/adiponectin levels in patients with SSc and healthy controls and to evaluate their possible relationship with frequently used laboratory markers and clinical findings.

MATERIAL AND METHODS

The study included 48 Caucasian female patients with SSc and 38 healthy controls. Serum concentrations of leptin and adiponectin were measured in patients and controls using commercially available ELISA Kits (Quantikine ELISA Kit R&D Systems, Minneapolis, MN, USA). The results were assessed by the Mann-Whitney U-test and Spearman's correlation test.

RESULTS

Leptin and adiponectin levels correlated with body mas index in SSc patients (r = 0.495, p = 0.000398 and r = -0.306; p = 0.0342) in contrast to healthy controls (p = 0.070 and p = 0.256, respectively), and, in SSc patients only, a strong negative correlation was observed between leptin and adiponectin serum levels (r = -0.314; p = 0.0312). Diffuse form of the disease (dcSSc) was associated with significantly lower serum adiponectin levels (8638.62 ±10382.62). Active disease was associated with significantly lower leptin concentration (13700.49 ±18293.32) and there was a significant negative correlation between leptin serum level and activity index score (r = -0.342; p = 0.0185).

CONCLUSIONS

The results of our study indicate that leptin levels might correlate with disease activity and subtype in SSc patients.

Abnormal pulmonary artery systolic pressure response after exercise in systemic sclerosis patients: A PRISMA-compliant meta-analysis

BACKGROUND

Pulmonary artery systolic pressure (PASP) is an important parameter for detecting pulmonary arterial hypertension (PAH). The difference between rest PASP and post-exercise PASP (ΔPASP) may play a role in predicting and screening resting PAH. The aim of this study is to analyze ΔPASP in systemic sclerosis (SSc) patients with PAH or non-PAH and suggest a cutoff value of ΔPASP for detection of PAH.

METHODS

PubMed, Embase, and Web of Science were searched for relevant publications up to July 7, 2018. Characteristics of control, no PAH, exercise-induced PAH (EIPH) and PAH subgroups in SSc patients were extracted. R 3.5.0 with the "meta" package was used to conduct this meta-analysis.

RESULTS

Twelve articles involving 1279 patients were included in this study. The subgroups meta-analysis showed pooled mean ΔPASP in different subgroups: control group (8.6 mmHg, 95% CI: 6.9-10.5), no PAH group (12.2 mmHg, 95% CI: 11.2-13.2), EIPH group (26.0 mmHg, 95% CI: 24.2-27.7) and PAH group (36.2 mmHg, 95% CI: 29.7-42.7).

CONCLUSION

Combining the results of our study with the previous studies, an abnormal increase in PASP after exercise could indicate the development of PAH in SSc patients. In addition, if ΔPASP>29 mmHg, a high suspicion of PAH should be raised.

The Right Heart International Network (RIGHT-NET): Rationale, Objectives, Methodology, and Clinical Implications

The Right Heart International Network is a multicenter international study aiming to prospectively collect exercise Doppler echocardiography tests of the right heart pulmonary circulation unit (RHPCU) in large cohorts of healthy subjects, elite athletes, and individuals at risk of or with overt pulmonary hypertension. It is going to provide standardization of exercise stress echocardiography of RHPCU and explore the full physiopathologic response.

Stressing the Cardiopulmonary Vascular System: The Role of Echocardiography

The cardiopulmonary vascular system represents a key determinant of prognosis in several cardiorespiratory diseases. Although right heart catheterization is considered the gold standard for assessing pulmonary hemodynamics, a comprehensive noninvasive evaluation including left and right ventricular reserve and function and cardiopulmonary interactions remains highly attractive. Stress echocardiography is crucial in the evaluation of many cardiac conditions, typically coronary artery disease but also heart failure and valvular heart disease. In stress echocardiographic applications beyond coronary artery disease, the assessment of the cardiopulmonary vascular system is a cornerstone. The possibility of coupling the left and right ventricles with the pulmonary circuit during stress can provide significant insight into cardiopulmonary physiology in healthy and diseased subjects, can support the diagnosis of the etiology of pulmonary hypertension and other conditions, and can offer valuable prognostic information. In this state-of-the-art document, the topic of stress echocardiography applied to the cardiopulmonary vascular system is thoroughly addressed, from pathophysiology to different stress modalities and echocardiographic parameters, from clinical applications to limitations and future directions.

Aerobic and resistance exercise in systemic sclerosis: State of the art

INTRODUCTION

Patients with systemic sclerosis (SSc) experience reduced exercise capacity and muscle strength compared with healthy subjects. There are also indications of reduced levels of physical activity.

OBJECTIVE

To present the current knowledge of physical exercise in SSc.

RESULTS

Most studies presently available [three case studies, one single subject experimental design, one study comparing patients with healthy controls, one quasi experimental design (pre-post), two clinical trials and two random controlled trials] have included small samples of patients, mostly composed of patients with and without pulmonary involvement. It seems that patients with SSc without pulmonary involvement are able to perform and benefit from aerobic exercises of at least moderate intensity. Exercise tolerance, aerobic capacity, walking distance, muscle strength and muscle function as well as health-related quality of life (HRQL) have been found to be improved after participation in programmes including aerobic exercise and aerobic exercise combined with resistance exercises. Improvements seem to be only partially retained at follow up. Patients with pulmonary involvement may also experience improved muscle strength, physical and aerobic capacity, as well as HRQL following exercise.

CONCLUSIONS

Patients with SSc without pulmonary involvement can be recommended to be as physically active as the general population. Patients with mild pulmonary involvement can be recommended to be physically active by engaging in exercises of moderate intensity and to participate in moderate-load resistance exercises. Health professionals should inform patients with SSc about the importance of physical activity and avoidance of a sedentary lifestyle.

An official European Respiratory Society statement: pulmonary haemodynamics during exercise

There is growing recognition of the clinical importance of pulmonary haemodynamics during exercise, but several questions remain to be elucidated. The goal of this statement is to assess the scientific evidence in this field in order to provide a basis for future recommendations.

Right heart catheterisation is the gold standard method to assess pulmonary haemodynamics at rest and during exercise. Exercise echocardiography and cardiopulmonary exercise testing represent non-invasive tools with evolving clinical applications. The term “exercise pulmonary hypertension” may be the most adequate to describe an abnormal pulmonary haemodynamic response characterised by an excessive pulmonary arterial pressure (PAP) increase in relation to flow during exercise. Exercise pulmonary hypertension may be defined as the presence of resting mean PAP <25 mmHg and mean PAP >30 mmHg during exercise with total pulmonary resistance >3 Wood units. Exercise pulmonary hypertension represents the haemodynamic appearance of early pulmonary vascular disease, left heart disease, lung disease or a combination of these conditions. Exercise pulmonary hypertension is associated with the presence of a modest elevation of resting mean PAP and requires clinical follow-up, particularly if risk factors for pulmonary hypertension are present. There is a lack of robust clinical evidence on targeted medical therapy for exercise pulmonary hypertension.

Physical activity and autoimmune diseases: Get moving and manage the disease

Physical activity, by definition, is any skeletal muscle body movement that results in energy expenditure. In the last few decades, a plethora of scientific evidences have accumulated and confirmed the beneficial role of physical activity as a modifiable risk factor for a wide variety of chronic diseases including cardiovascular diseases (CVDs), diabetes mellitus and cancer, among others. Autoimmune diseases are a heterogeneous group of chronic diseases, which occur secondary to loss of self-antigen tolerance. With the advent of biological therapies, better outcomes have recently been noted in the management of autoimmune diseases. Nonetheless, recent research highlights the salient role of modifiable behaviors such as physical inactivity on various aspects of the immune system and autoimmune diseases. Physical activity leads to a significant elevation in T-regulatory cells, decreased immunoglobulin secretion and produces a shift in the Th1/Th2 balance to a decreased Th1 cell production. Moreover, physical activity has been proven to promote the release of IL-6 from muscles. IL-6 released from muscles functions as a myokine and has been shown to induce an anti-inflammatory response through IL-10 secretion and IL-1β inhibition. Physical activity has been shown to be safe in most of autoimmune diseases including systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), multiple sclerosis (MS), inflammatory bowel diseases (IBD), as well as others. Additionally, the incidence of RA, MS, IBD and psoriasis has been found to be higher in patients less engaged in physical activity. As a general trend, patients with autoimmune diseases tend to be less physically active as compared to the general population. Physically active RA patients were found to have a milder disease course, better cardiovascular disease (CVD) profile, and improved joint mobility. Physical activity decreases fatigue, enhances mood, cognitive abilities and mobility in patients with MS. In SLE patients, enhanced quality of life and better CVD profile were documented in more physically active patients. Physically active patients with type 1 diabetes mellitus have a decreased risk of autonomic neuropathy and CVD. Both fibromyalgia and systemic sclerosis patients report decreased disease severity, pain, as well as better quality of life with more physical activity. Further, SSc patients improve their grip strength, finger stretching and mouth opening with increased level of exercise. The purpose of this paper is to review the clinical evidence regarding the safety, barriers to engagement, and impact of physical activity on autoimmune diseases.

Changes in pulmonary exercise haemodynamics in scleroderma: a 4-year prospective study

Pulmonary arterial hypertension (PAH) is a feared complication of systemic sclerosis. In this prospective cohort study, we monitored the changes in resting and exercise pulmonary haemodynamics of scleroderma patients without initial PAH over a mean follow-up period of ∼4 years.

All patients underwent exercise echocardiography and cardiopulmonary exercise testing at baseline and follow-up. A subgroup underwent exercise right heart catheter (RHC) investigations. The primary end-point was the echocardiographic systolic pulmonary arterial pressure at 50 W exercise (sPAP50).

We included 99 patients, of whom 58 had a complete dataset. Three out of 99 patients developed RHC-confirmed PAH (0.75 cases per 100 patient-years). sPAP50 increased (p<0.001) and peak oxygen uptake (secondary end-point) decreased significantly (p=0.001) during follow-up, but there was no significant change in resting sPAP (p=0.38). In the RHC subgroup (n=28), mean (m)PAP and pulmonary vascular resistance at 50 W increased significantly (p=0.02 and p=0.002, respectively), but resting mPAP was unchanged.

Scleroderma patients without PAH develop a mild but significant deterioration of pulmonary exercise haemodynamics and exercise capacity over a 4-year follow-up period, indicating a progression of pulmonary vascular disease. The manifestation rate of RHC-confirmed PAH was 0.75 cases per 100 patient-years.

Exercise echocardiography for the assessment of pulmonary hypertension in systemic sclerosis: a systematic review

BACKGROUND

Pulmonary arterial hypertension (PAH) complicates the course of systemic sclerosis (SSc) and is associated with poor prognosis. The elevation of systolic pulmonary arterial pressure (sPAP) during exercise in patients with SSc with normal resting haemodynamics may anticipate the development of PAH. Exercise echocardiography (ExEcho) has been proposed as a useful technique to identify exercise-induced increases in sPAP, but it is unclear how to clinically interpret these findings. In this systematic review, we summarize the available evidence on the role of exercise echocardiography to estimate exercise-induced elevations in pulmonary and left heart filling pressures in patients with systemic sclerosis.

METHODS

We conducted a systematic review of the literature using MEDLINE, Cochrane Library and Web of Knowledge, using the vocabulary terms: ('systemic sclerosis' OR 'scleroderma') AND ('exercise echocardiography') AND ('pulmonary hypertension'). Studies including patients with SSc without a prior diagnosis of PAH, and subjected to exercise echocardiography were included. All searches were limited to English and were augmented by review of bibliographic references from the included studies. The quality of evidence was assessed by the Effective Public Health Practice Project system.

RESULTS

We identified 15 studies enrolling 1242 patients, who were mostly middle-aged and female. Several exercise methods were used (cycloergometer, treadmill and Master's two step), with different protocols and positions (supine, semi-supine, upright); definition of a positive test also varied widely. Resting estimated sPAP levels varied from 18 to 35 mm Hg, all in the normal range. The weighted means for estimated sPAP were 22.2 ± 2.9 mmHg at rest and 43.0 ± 4.3 mmHg on exercise; more than half of the studies reported mean exercise sPAP ≥40 mmHg. The assessment of left ventricular diastolic function on peak exercise was reported in a minority of studies; however, when assessed, surrogate variables of left ventricular (LV) diastolic dysfunction were associated with higher sPAP on exercise.

CONCLUSIONS

We found very high heterogeneity in the methods, the protocols and the estimated sPAP response to exercise. LV diastolic dysfunction was common and was associated with greater elevation of sPAP on exercise.

Rest and exercise echocardiography for early detection of pulmonary hypertension

Early detection of pulmonary hypertension (PH) is essential to ensure that patients receive timely and appropriate treatment for this progressive disease. Rest and exercise echocardiography has been used to screen patients in an attempt to identify early stage PH. However, current PH guidelines recommend against exercise tests because of the lack of evidence. We reviewed previous studies to discuss the current standpoint concerning rest and exercise echocardiography in PH. Around 20 exercise echocardiography studies were included to assess the cutoff value for exercise-induced pulmonary hypertension (EIPH). Approximately 40 exercise echocardiography studies were also included to evaluate the pulmonary artery pressure-flow relationship as assessed by the slope of the mean pulmonary artery pressure and cardiac output (ΔmPAP/ΔQ). There were several EIPH and ΔmPAP/ΔQ reference values in individuals with pulmonary vascular disease. We believed that assessing the ΔmPAP/ΔQ makes sense from a physiological standpoint, and the clinical value should be confirmed in future studies. Exercise echocardiography is an appealing alternative in PH. Further studies are needed to assess the prognostic value of the pulmonary artery pressure-flow relationship in high-risk subjects.

Stress Doppler echocardiography for early detection of systemic sclerosis-associated pulmonary arterial hypertension

INTRODUCTION

In patients with systemic sclerosis (SSc), associated pulmonary arterial hypertension (SSc-APAH) is the leading cause of death. The objective of this prospective screening study was to analyse sensitivity and specificity of stress Doppler echocardiography (SDE) in detecting pulmonary hypertension (PH).

METHODS

Pulmonary artery pressures and further parameters of PH were assessed by echocardiography and right heart catheterisation (RHC) at rest and during exercise in patients with SSc. Investigators of RHC were blinded to the results of non-invasive measurements.

RESULTS

Of 76 patients with SSc (64 were female and mean age was 58±14 years), 22 (29 %) had manifest PH confirmed by RHC: four had concomitant left heart diseases, three had lung diseases, and 15 had SSc-APAH. Echocardiography at rest missed PH diagnosis in five of 22 patients with PH when a cutoff value for systolic pulmonary arterial pressure (PASP) was more than 40 mm Hg at rest. The sensitivity of echocardiography at rest was 72.7 % (95 % confidence interval (CI) 0.52-0.88), and specificity was 88.2 % (95 % CI 0.78-0.95). When a cutoff value for PASP was more than 45 mm Hg during low-dose exercise, SDE missed PH diagnosis in one of the 22 patients with PH and improved sensitivity to 95.2 % (95 % CI 0.81-1.0) but reduced specificity to 84.9 % (95 % CI 0.74-0.93). Reduction of specificity was partly due to concomitant left heart disease.

CONCLUSIONS

The results of this prospective cross-sectional study using RHC as gold standard in all patients showed that SDE markedly improved sensitivity in detecting manifest PH to 95.2 % compared with 72.7 % using echocardiography at rest only. Thus, for PH screening in patients with SSc, echocardiography should be performed at rest and during exercise.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01387035. Registered 29 June 2011.