Reduced Exercise Capacity and Stress-Induced Pulmonary Hypertension in Patients With Scleroderma

Use of exercise tests in screening for pulmonary arterial hypertension in systemic sclerosis: A systematic literature review

Background and objective

Patients with systemic sclerosis (SSc) and pulmonary arterial hypertension (PAH) have a poor prognosis, accounting for 30% of all SSc-related deaths. Guidelines recommend annual screening for PAH regardless of symptoms, as early treatment improves outcomes. Current protocols include combinations of clinical features, biomarkers, pulmonary function tests, and echocardiography. None include exercise testing, although early-stage PAH may only be evident during exercise. This systematic review assessed the performance of exercise tests in predicting the presence of PAH in patients with SSc, where PAH was confirmed through right heart catheterisation (RHC).

Methods

Comprehensive literature searches were performed using MEDLINE, EMBASE, Cochrane Database of Systematic Reviews and Cochrane Central Register of Controlled Trails, CINAHL, Scopus and Web of Science from inception to May 2023. Articles were screened for eligibility by two independent reviewers. Eligibility criteria included the use of a non-invasive exercise test to screen adult patients to detect PAH in a population without a previous diagnosis of PAH, with diagnosis confirmed by RHC.

Results

Eight studies met the inclusion criteria, describing at least one of three different non-invasive exercise tests: cardiopulmonary exercise test, six-minute walk test and stress Doppler echocardiography. All studies found that exercise tests had some ability to predict the presence of PAH, with sensitivity between 50% and 100% and specificity from 73% to 91%.

Conclusion

Exercise tests are infrequently used for screening for PAH in SSc but can predict the presence of PAH. More data are required to establish which tests are most effective.

Pulmonary artery pressure-perfusion relation during exercise in patients with chronic thromboembolic pulmonary hypertension using pulmonary arteriography and right-heart catheterization

Background

In pulmonary hypertension (PH), pulmonary artery pressure (PAP) does not increase to pulmonary perfusion (PP) < 50%. During exercise, PAP may be increased even at PP > 50% for the early detection of PP disorders. The relationship between PP estimated by pulmonary angiography (PAG) and PAP was evaluated in patients with chronic thromboembolic PH (CTEPH) treated by balloon pulmonary angioplasty with near-normal PH.

Methods

Thirty-one patients (age 60 ± 11 years) with CTEPH underwent catheterization at rest and during exercise. Each segmental PP was determined by visualization of its segmental pulmonary artery and graded from 0 to 3 in the PAG. PP was estimated as the percentage PAG (%PAG) score-%summed total of all segmental PP/the full score-54.

Results

The mean PAP (mPAP) increased from 28 ± 6 mmHg to 46 ± 10 mmHg during exercise. Transpulmonary pressure gradient, the value of mPAP with the pulmonary artery wedge pressure substituted at peak exercise, was negatively correlated with %PAG score (rs = -0.56, p < 0.001) and elevated at > 50% PP.

Conclusions

The PAP-PP relationship at peak exercise was correlated, shifting from the relationship at rest, and the PAP started to rise with PP > 50%.

Survival in Swedish patients with systemic sclerosis: a nationwide population-based matched cohort study

OBJECTIVES

To conduct the first-ever nationwide, population-based cohort study investigating survival patterns of all patients with incident SSc in Sweden compared with matched individuals from the Swedish general population.

METHODS

We used the National Patient Register to identify patients with incident SSc diagnosed between 2004 and 2015 and the Total Population Register to identify comparators (1:5), matched on sex, birth year and residential area. We followed them until death, emigration or the end of 2016. Follow-up of the general population comparators started the same date as their matched patients were included. We estimated all-cause survival using the Kaplan-Meier method, crude mortality rates and hazard ratios (HRs) using flexible parametric models.

RESULTS

We identified 1139 incident patients with SSc and 5613 matched comparators. The median follow-up was 5.0 years in patients with SSc and 6.0 years for their comparators. During follow-up, 268 deaths occurred in patients with SSc and 554 in their comparators. The 5-year survival was 79.8% and the 10-year survival was 67.7% among patients with SSc vs 92.9% and 84.8%, respectively, for the comparators (P < 0.0001). The mortality rate in patients with SSc was 42.1 per 1000 person-years and 15.8 per 1000 person-years in their comparators, corresponding to an HR of 3.7 (95% CI 2.9, 4.7) at the end of the first year of follow-up and 2.0 (95% CI 1.4, 2.8) at the end of the follow-up period.

CONCLUSION

Despite advances in understanding the disease and in diagnostic methods over the past decades, survival is still severely impacted in Swedish patients diagnosed with SSc between 2004 and 2015.

Impact of Exercise-Induced Pulmonary Hypertension on Right Ventricular Function and on Worsening of Cardiovascular Risk in HIV Patients

Background and Aim: Exercise-induced pulmonary hypertension (ExPH) predicts clinical outcomes, such as all-cause mortality and cardiovascular (CV) hospitalizations, in patients with dyspnea on effort. We investigated its prognostic significance in human immunodeficiency virus (HIV)-affected patients. Methods: In 52 consecutive HIV patients with either low (n = 47) or intermediate probability (n = 5) of PH at rest, we evaluated—at time 0 and after 2 years—the prognostic determinants of CV risk, according to the 2015 European Society of Cardiology (ESC)/European Respiratory Society (ERS) Guidelines. Patients were classified with or without ExPH at stress echocardiography (ESE) and cardiopulmonary exercise test (CPET). We then related ExPH at time 0 with clinical worsening (CV risk score increase >20% after 2 years). Results: Right ventricle (RV) systolic function was significantly reduced in patients with ExPH compared to those without ExPH at CPET. This also occurred in patients with intermediate/high probability compared to those with low probability of ExPH at ESE. The former exhibited worse values of TAPSE and FAC (p < 0.001 and p = 0.01, respectively). A significantly higher proportion of patients with ExPH (CPET) or with intermediate/high probability of ExPH (ESE) had higher sPAP (p < 0.001), mPAP (p = 0.004) and higher TRV (p = 0.006), as well as higher right atrial area (p < 0.001) and indexed right atrial volume (p = 0.004). Total pulmonary vascular resistance (expressed by the ratio between TRV and the velocity-time integral at the level of the right ventricular outflow tract) was higher both in patients with ExPH and in those with intermediate/high probability of ExPH (p < 0.001). Patients with intermediate/high probability of ExPH at ESE showed a trend (p = 0.137) towards clinical worsening compared to those with low probability of ExPH. No patients with low probability of ExPH had a >20% increased CV risk score after 2 years. We found an association between higher NT-proBNP and the presence or intermediate/high probability of ExPH after 2 years (p = 0.048 at CPET, p = 0.033 at ESE). Conclusions: The assessment of ExPH may predict a trend of increasing CV risk score over time. If confirmed at a longer follow-up, ExPH could contribute to better risk stratification in HIV patients.

Exercise-Induced Pulmonary Hypertension Is Associated with High Cardiovascular Risk in Patients with HIV

Background and Aim: Pulmonary hypertension (PH) at rest can be preceded by the onset of exercise-induced PH (ExPH). We investigated its association with the cardiovascular (CV) risk score in patients with human immunodeficiency virus (HIV). Methods: In 46 consecutive patients with HIV with low (n = 43) or intermediate (n = 3) probability of resting PH, we evaluated the CV risk score based on prognostic determinants of CV risk. Diagnosis of ExPH was made by cardiopulmonary exercise test (CPET) and exercise stress echocardiogram (ESE). Results: Twenty-eight % (n = 13) of the enrolled patients had ExPH at both CPET and ESE, with good agreement between the two methods (Cohen’s kappa = 0.678). ExPH correlated directly with a higher CV score (p < 0.001). Patients with a higher CV score also had lower CD4+ T-cell counts (p = 0.001), a faster progression to acquired immunodeficiency syndrome (p < 0.001), a poor immunological response to antiretroviral therapy (p = 0.035), higher pulmonary vascular resistance (p = 0.003) and a higher right atrial area (p = 0.006). Conclusions: Isolated ExPH is associated with a high CV risk score in patients with HIV. Assessment of ExPH may better stratify CV risk in patients with HIV.

Tetrahydrobiopterin Administration Augments Exercise-Induced Hyperemia and Endothelial Function in Patients With Systemic Sclerosis

Systemic sclerosis (SSc) is a rare, auto-immune disease with variably progressive fibrosis of the skin and internal organs, as well as vascular dysfunction. Recently, we demonstrated a decrement in exercising skeletal muscle blood flow and endothelium-dependent vasodilation in SSc, but the mechanisms responsible for these impairments have not been investigated. Thus, we sought to determine if acute administration of tetrahydrobiopterin (BH₄), an essential cofactor for endothelial nitric oxide synthase (eNOS), would improve hyperemia and brachial artery vasodilation during progressive handgrip exercise in SSc. Thirteen patients with SSc (63 ± 11 years) participated in this placebo-controlled, randomized, double-blind, crossover study. Tetrahydrobiopterin (10 mg/kg) administration resulted in a ~4-fold increase in circulating BH₄ concentrations (P < 0.05). Cardiovascular variables at rest were unaffected by BH₄ (P > 0.05). During handgrip exercise, BH₄ administration increased brachial artery blood flow (placebo: 200 ± 87; BH₄: 261 ± 115 ml/min; P < 0.05) and vascular conductance (placebo: 2.0 ± 0.8; BH₄: 2.5 ± 1.0 ml/min/mmHg; P < 0.05), indicating augmented resistance artery vasodilation. Tetrahydrobiopterin administration also increased brachial artery vasodilation in response to exercise (placebo: 12 ± 6; BH₄: 17 ± 7%; P < 0.05), resulting in a significant upward shift in the slope relationship between Δ brachial artery vasodilation and Δ shear rate (placebo: 0.030 ± 0.007; BH₄: 0.047 ± 0.007; P < 0.05) that indicates augmented sensitivity of the brachial artery to vasodilate to the sustained elevations in shear rate during handgrip exercise. These results demonstrate the efficacy of acute BH₄ administration to improve both resistance and conduit vessel endothelial function in SSc, suggesting that eNOS recoupling may be an effective strategy for improving vasodilatory capacity in this patient group.

Low-Dose Dobutamine Stress Echocardiography for the Early Detection of Pulmonary Arterial Hypertension in Selected Patients with Systemic Sclerosis Whose Resting Echocardiography Is Non-Diagnostic for Pulmonary Hypertension

BACKGROUND

Dobutamine stress echocardiography (DSE) has limited application in systemic sclerosis (SSc). We examined DSE usefulness in revealing pulmonary arterial hypertension (PAH) in selected SSc patients whose resting echocardiography for pulmonary hypertension (PH) was non-diagnostic.

METHODS

Forty SSc patients underwent right heart catheterization (RHC) and, simultaneously, low-dose DSE (incremental doses up to 20 μg/kg/min). Inclusion criteria were: preserved left and right ventricular (RV) function (tricuspid annulus plane systolic excursion [TAPSE] ≥ 16 mm and tissue Doppler imaging-derived systolic velocity of tricuspid annulus [RVS'] > 10 cm/s), normal pulmonary function tests, and baseline maximal tricuspid regurgitation (TR) velocity of 2.7-3.2 m/s.

RESULTS

Of 36 patients who completed DSE, resting RHC diagnosed PAH in 12 patients (33.3%). At 20 μg/kg/min, patients with PAH had higher TR velocity, higher pulmonary arterial pressure measured by RHC, and lower RV inotropic response compared with patients without PAH. A cut-off value of maximal TR velocity >3.1 m/s had a sensitivity of 80%, a specificity of 84.2%, and an accuracy of 82.4% for the detection of PAH.

CONCLUSIONS

Low-dose DSE has a satisfactory diagnostic accuracy for the early detection of PAH in highly selected SSc patients whose baseline echocardiographic measurements for PH lie in the gray zone.

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.

Exercise-induced pulmonary hypertension in HIV patients: Association with poor clinical and immunological status

BACKGROUND AND AIM

Exercise-induced pulmonary hypertension (Ex-PH) may represent the earliest sign of pulmonary arterial hypertension (PAH) in human immunodeficiency virus (HIV) patients. We investigated its association with clinical and immunological status, virologic control, and response to antiviral therapy.

METHODS

In 32 consecutive HIV patients with either low (n = 29) or intermediate probability (n = 3) of PH at rest, we evaluated the association of isolated ExPH with: time to HIV diagnosis; CD4+ T-cell count; clinical progression to acquired immunodeficiency syndrome (AIDS); development of resistance to antiretroviral therapy (ART); HIV RNA levels; time to beginning of ART; current use of protease inhibitors; combination of ART with boosters (ritonavir or cobicistat); immuno-virologic response to ART; and ART discontinuation. Isolated ExPH at stress echocardiography (ESE) was defined as absence of PH at rest and systolic pulmonary arterial pressure (sPAP) >45 mmHg or a >20 mmHg increase during low-intensity exercise cardiac output (<10 L/min).

RESULTS

In our cohort, 22% (n = 7) of the enrolled population developed ExPH which was inversely related to CD4+ T-cell count (p = 0.047), time to HIV diagnosis (p = 0.014) and time to onset of ART (p = 0.041). Patients with ExPH had a worse functional class than patients without ExPH (p < 0.001). ExPH and AIDS showed a trend (p = 0.093) to a direct relationship. AIDS patients had a higher pulmonary vascular resistance compared to patients without ExPH (p = 0.020) at rest echocardiography.

CONCLUSIONS

The presence of isolated ExPH associates with a worse clinical status and poor immunological control in HIV patients. Assessment of ExPH by ESE may help identify subgroups of HIV patients with a propensity to develop subclinical impairment of pulmonary circulation following poor control of HIV infection.

The effect of dopamine on pulmonary diffusing capacity and capillary blood volume responses to exercise in young healthy humans

NEW FINDINGS

What is the Central question? Does dopamine, a pulmonary vascular vasodilator, contribute to the regulation of pulmonary diffusing capacity and capillary blood volume responses to exercise and exercise tolerance? What are the main findings and their importance? Dopamine appears not to be important for regulating pulmonary diffusing capacity or pulmonary capillary blood volume during exercise in healthy participants. Dopamine blockade trials demonstrated that endogenous dopamine is important for maintaining exercise tolerance; however, exogenous dopamine does not improve exercise tolerance.

ABSTRACT

Pulmonary capillary blood volume (V_c ) and diffusing membrane capacity (D_m ) expansion are important contributors to the increased pulmonary diffusing capacity (DL_CO ) observed during upright exercise. Dopamine is a pulmonary vascular vasodilator, and recent studies suggest that it may play a role in V_c regulation through changes in pulmonary vascular tone. The purpose of this study was to examine the effect of exogenous dopamine and dopamine receptor-2 (D₂ -receptor) blockade on DL_CO , V_c and D_m at baseline and during cycle exercise, as well as time-to-exhaustion at 85% of V ̇ O 2 peak . We hypothesized that dopamine would increase DL_CO , V_c , D_m and time-to-exhaustion, while D₂ -receptor blockade would have the opposite effect. We recruited 14 young, healthy, recreationally active subjects ( V ̇ O 2 peak 45.8 ± 6.6 ml kg^-1  min^-1 ). DL_CO , V_c and D_m were determined at baseline and during exercise at 60% and 85% of V ̇ O 2 peak under the following randomly assigned and double blinded conditions: (1) intravenous saline and placebo pill, (2) intravenous dopamine (2 µg kg^-1  min^-1 ) and placebo pill, and (3) intravenous saline and D₂ -receptor antagonist (20 mg oral metoclopramide). Exogenous dopamine and dopamine blockade had no effect on DL_CO , V_c and D_m responses at baseline or during exercise. Dopamine blockade reduced time-to-exhaustion by 47% (P = 0.04), but intravenous dopamine did not improve time-to-exhaustion. While dopamine modulation did not affect DL_CO , V_c or D_m , the reduction in time-to-exhaustion with D₂ -receptor blockade suggests that endogenous dopamine is important for exercise tolerance.

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.

Accuracy of Doppler echocardiography in the hemodynamic assessment of pulmonary circulation in patients with systemic sclerosis

PURPOSE

Pulmonary hypertension (PH) is an ominous complication in systemic sclerosis patients (SSc) and echocardiography is a screening tool for its detection. The goal of this study was to assess the reliability of resting and exercise echo Doppler parameters with data obtained by right heart catheterization (RHC).

MATERIAL AND METHODS

We included 91 patients (84 F, 53.3 ± 15.2 years) with SSc. Transthoracic echocardiography followed by exercise Doppler-echocardiography (EDE) were performed. A positive EDE was defined as a ≥20 mmHg increase in tricuspid regurgitation peak gradient (TRPG). RHC with exercise was performed in positive EDE patients and/or in subjects with resting TRPG > 31 mmHg.

RESULTS

Finally, RHC was performed in 20 patients. The correlation for the echocardiography and invasive measurement of systolic (sPAP) and mean (mPAP) pulmonary artery pressure was r = 0.66 (p = 0.001) and r = 0.7 (p = 0.001), respectively. We also found significant correlation between echocardiography and invasive measurement of exercise sPAP r = 0.68 (p = 0.001) and exercise mPAP r = 0.67 (p = 0.002). There was a correlation between pulmonary vascular resistance (PVR) assessed by echocardiography and measured by RHC r = 0.49, p = 0.027. The equation derived within our population was: PVR by echocardiography = 9.6*TRV/TVI_RVOT+0.068. We also performed ROC analysis to predict PVR > 2 WU. Our results highlight that sPAP has the highest AUC (0.802, 95% CI 0.585-1).

CONCLUSION

Doppler resting and exercise echocardiography may provide a reliable, noninvasive method for determining resting and exercise sPAP, mPAP, and PVR in SSc patients, although it may underestimate or overestimate these values in some individuals. Doppler echocardiography does not replace RHC for definite hemodynamic assessment of suspected PH.

Reliability and validity of the German version of the Myositis Activities Profile (MAP) in patients with inflammatory myopathy

The Myositis Activity Profile (MAP) is the only disease-specific questionnaire to assess limitations in activities of daily living (ADL) in patients with inflammatory myopathy (IM). Because a German version does not currently exist, this study’s aim was to translate the MAP and assess reliability and construct validity of the new version. Therefore, a cross-cultural adaptation was performed following international guidelines. Forty-eight patients with IM completed the German-MAP, twice within two weeks. They were also assessed using the Health Assessment Questionnaire (HAQ), 36-Item Short Form Survey (SF36), Manual Muscle Test (MMT8), Quantitative Muscle Testing (QMT) and Functional Index (FI-2). For discriminant validity, 48 age-and gender-matched healthy controls completed the German-MAP. Reliability was assessed using weighted kappa (K_w). Correlations between the MAP and the HAQ, the physical (PCM) and mental (MCS) component scores of SF36 and the MMT8 and QMT muscle tests were assessed using Spearman correlation analysis. Discriminative validity was assessed by calculating the Area under the Curve (AUC). The German-MAP showed substantial reliability for the four subscales (K_w: 0.65–0.71) and moderate to substantial reliability for the single items (K_w: 0.57–0.77). The MAP showed good construct validity (high correlations with HAQ and PCM, moderate with FI-2, QMT and MMT8 and poor with MCS and pain) and acceptable discrimination for three subscales and two single items (AUC: 0.65–0.79). In conclusion, the German-MAP appears to be a reliable and valid questionnaire to assess ADL-limitations in patients with IM. Further research is required, both to substantiate these results and to evaluate responsiveness.

Progression of Left Ventricular Myocardial Dysfunction in Systemic Sclerosis: A Speckle-tracking Strain Echocardiography Study

OBJECTIVE

Cardiac involvement is a main cause of mortality in systemic sclerosis (SSc). Its detection remains challenging using conventional echocardiography and little is known about its potential progression. This study assessed changes in cardiac performance over time in a prospective cohort of patients with SSc, including echocardiographic speckle-tracking strain analysis.

METHODS

The study included 234 patients with SSc [196 women, age 52 ± 14 yrs, 165 limited SSc, time since diagnosis 5.2 yrs, interquartile range (IQR) 2.9-11.3]. Clinical variables, laboratory tests, pulmonary function tests, and echocardiographic measures were recorded at baseline and followup (median 2.3 yrs, IQR 1.3-3.9). Additionally, left ventricular (LV) systolic function was assessed with global longitudinal strain (GLS) by echocardiographic speckle-tracking analysis.

RESULTS

At followup, GLS had significantly worsened (-21% ± 2 vs -19% ± 2, p < 0.001) while LV ejection fraction had not changed (62% ± 7 vs 61% ± 8, p = 0.124). In particular, 39 patients showed a significant deterioration of GLS as defined by a ≥ 15% decrease, which was accompanied by a concomitant worsening of proximal muscle weakness, lung fibrosis, renal function, LV diastolic function, and right ventricular systolic function. Baseline variables associated with ≥ 15% deterioration in GLS were proximal muscle weakness (OR 3.437, 95% CI 1.13-10.43, p = 0.020), decreased DLCO (OR 3.621, 95% CI 1.25-10.51, p = 0.049), and LV diastolic dysfunction (OR 2.378, 95% CI 1.07-5.27, p = 0.033).

CONCLUSION

In patients with SSc, progression of LV systolic dysfunction was demonstrated by GLS but not by LV ejection fraction. Proximal muscle weakness, DLCO, and LV diastolic dysfunction may identify patients at risk for progressive LV systolic dysfunction and in need of closer cardiac monitoring.

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.

Assessment of Right Ventricular Function in Pulmonary Hypertension with Multimodality Imaging

Pulmonary hypertension (PH) is defined as resting mean pulmonary artery pressure ≥ 25 mmHg and is caused by multiple etiologies including heart, lung or other systemic diseases. Evaluation of right ventricular (RV) function in PH is very important to plan treatment and determine prognosis. However, quantification of volume and function of the RV remains difficult due to complicated RV geometry. A number of imaging tools has been utilized to diagnose PH and assess RV function. Each imaging technique including conventional echocardiography, three-dimensional echocardiography, strain echocardiography, computed tomography and cardiac magnetic resonance imaging has-advantages and limitations and can provide unique information. In this article, we provide a comprehensive review of the utility, advantages and shortcomings of the multimodality imaging used to evaluate patients with PH.

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.

Design of the exercise MRI evaluation of HIV-pulmonary arterial hypertension longitudinal determinants (EXALTED) trial

BACKGROUND

Pulmonary arterial hypertension (PAH) is a potentially serious cause of dyspnea and exercise limitation in patients with HIV infection. In this trial, we propose using exercise MRI in conjunction with cardiopulmonary testing to delineate PAH from other causes of cardiovascular dysfunction, identify individuals with exercise-induced PAH who are at high risk of developing resting PAH, and provide longitudinal estimates of progression of PAH and right ventricular function.

METHODS

In this prospective observational study, HIV patients with dyspnea and exercise limitation in the absence of identifiable causes and those who meet the inclusion criteria will be enrolled based on resting pulmonary artery pressure (≤ or >40 mmHg) on a screening echocardiogram and exercise limitation on the Modified Medical Research Council dyspnea scale. Patients without evidence of resting PAH will be enrolled into both rest and exercise MRI and cardiopulmonary testing protocol, whereas patients with evidence of PAH on resting echocardiograms will undergo only resting cardiac MRI studies to evaluate right ventricular function and fibrosis. Both patient subgroups will be followed for 24 months to obtain longitudinal progression of the disease. In a sub-study, we will further analyze inflammatory variables that may predict these changes, thus allowing early identification of these patients.

IMPLICATIONS AND CONCLUSIONS

This trial will be the first study to provide an understanding of the mechanisms underpinning the functional deterioration of the right ventricle in patients with HIV and will impart insight into the immune mediators of PAH progression and right ventricular functional deterioration in patients with HIV-PAH.

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.

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.

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.

Readdressing the entity of exercise pulmonary arterial hypertension

Exercise pulmonary hypertension (EPH) indicates an abnormally elevated pulmonary artery pressure (PAP) during exercise. The physiological range of PAP during exercise remains poorly defined and, therefore, a universally accepted definition of EPH remains elusive. Nevertheless, previous data concerning the distribution of PAP in normal populations and more recent retrospective clinical data enhanced our ability to define EPH. EPH can impair exercise capacity and cause dyspnea. The underlying pathophysiology of the arterial form of EPH (EPAH) appears to be similar to that seen in resting pulmonary arterial hypertension (PAH), and EPAH individuals are at risk of developing resting PAH. Patients with collagen vascular disease, especially scleroderma, are at risk for EPAH and its presence indicates a relatively poor prognosis. The prevalence of EPAH in scleroderma may be as high as 50%. The utility of pulmonary vasodilator therapy for EPAH is not well defined; however, a sizable subgroup of EPAH patients will achieve an improvement in symptoms.

Short-Term Pulmonary Rehabilitation for a Female Patient with Chronic Scleroderma under a Single-Case Research Design

Although previously proposed that chronic scleroderma should be cared for clinically and early rehabilitation should be performed in hospital by a chest physical therapist, little evidence is currently available on its benefits. Therefore, this study demonstrated the benefits of short-term pulmonary rehabilitation during hospitalization in a female patient with chronic scleroderma. The aim of rehabilitation was to improve ventilation and gas exchange by using airway clearance, chest mobilization, and breathing-relearning techniques, including strengthening the respiratory system and the muscles of the limbs by using the BreathMax^® device and elastic bands. Gross motor function and activities of daily life were regained by balancing, sitting, and standing practices. Data on minimal chest expansion, high dyspnea, high respiratory rate, and low maximal inspiratory mouth pressure were recorded seven days before rehabilitation or at the baseline period. But there was a clinically significant improvement in dyspnea, chest expansion, maximal inspiratory mouth pressure, and respiratory rate, when compared to baseline data, which were recorded by a chest physical therapist during seven days of rehabilitation. Furthermore, physicians decided to stop using a mechanical ventilator, and improvement in functional capacity was noted. Therefore, in the case of chronic and stable scleroderma, short-term rehabilitation during hospitalization for chest physical therapy possibly shows clinical benefits by improving both pulmonary function and physical performance.

Exercise-induced brachial artery blood flow and vascular function is impaired in systemic sclerosis

Systemic sclerosis (SSc) is a rare autoimmune disease characterized by debilitating fibrosis and vascular dysfunction; however, little is known about the circulatory response to exercise in this population. Therefore, we examined the peripheral hemodynamic and vasodilatory responses to handgrip exercise in 10 patients with SSc (61 ± 4 yr) and 15 age-matched healthy controls (56 ± 5 yr). Brachial artery diameter, blood flow, and mean arterial pressure (MAP) were determined at rest and during progressive static-intermittent handgrip exercise. Patients with SSc and controls were similar in body stature, handgrip strength, and MAP; however, brachial artery blood flow at rest was nearly twofold lower in patients with SSc compared with controls (22 ± 4 vs. 42 ± 5 ml/min, respectively; P < 0.05). Additionally, SSc patients had an ∼18% smaller brachial artery lumen diameter with an ∼28% thicker arterial wall at rest (P < 0.05). Although, during handgrip exercise, there were no differences in MAP between the groups, exercise-induced hyperemia and therefore vascular conductance were ∼35% lower at all exercise workloads in patients with SSc (P < 0.05). Brachial artery vasodilation, as assessed by the relationship between Δbrachial artery diameter and Δshear rate, was significantly attenuated in the patients with SSc (P < 0.05). Finally, vascular dysfunction in the patients with SSc was accompanied by elevated blood markers of oxidative stress and attenuated endogenous antioxidant activity (P < 0.05). Together, these findings reveal attenuated exercise-induced brachial artery blood flow and conduit arterial vasodilatory dysfunction during handgrip exercise in SSc and suggest that elevated oxidative stress may play a role.

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.

Prediction of new onset of resting pulmonary arterial hypertension in systemic sclerosis

BACKGROUND

Early detection of pulmonary arterial hypertension (PH) is crucial in systemic scleroderma. However, predictors of new onset of resting PH during follow-up (FUPH) have been poorly explored.

AIM

To determine whether nailfold videocapillaroscopy (NVC) grade and exercise echocardiographic variables are predictors of FUPH.

METHODS

We prospectively enrolled 40 patients with systemic sclerosis (age 54±13 years; 68% women). All patients underwent graded semisupine exercise echocardiography and NVC. Baseline resting PH and FUPH were defined as systolic pulmonary arterial pressure (sPAP)>35 mmHg, and exercise-induced PH (EIPH) as exercise sPAP>50 mmHg.

RESULTS

Seventeen patients developed EIPH (43%). During follow-up (FU) (25±15 months), 11 patients without baseline PH developed FUPH (28%), all from the EIPH group. Patients with FUPH were significantly older (60±14 vs 50±12 years; P=0.04), had higher resting and exercise sPAP (30±4 vs 22±5 and 60±12 vs 40±11 mmHg, respectively; P<0.0001) and a higher exercise E/e' ratio (9.4±0.7 vs 5.8±0.4; P=0.0003) and presented more frequently NVC grade>2 (90% vs 35%; P=0.0009). After adjustment for age, resting sPAP, exercise sPAP and NVC grade>2 were associated with maximal resting sPAP during follow-up and FUPH (P<0.05). Patients with both EIPH and NVC grade>2 had a very high incidence of FUPH (82%), and both variables remained strongly associated with FUPH after adjustment for age (hazard ratio 11.6, 95% confidence interval 2.4-55.3; P=0.002).

CONCLUSION

Exercise echocardiography and NVC can identify a subgroup of patients with systemic sclerosis who are at risk of developing FUPH.

Risk factors for severity and manifestations in systemic sclerosis and prediction of disease course

Systemic sclerosis (SSc, or scleroderma) is a rheumatic disease with distinct features that encompass autoimmunity, vascular lesions (vasculopathy) and tissue fibrosis. The disease has a high morbidity and mortality compared with other rheumatic diseases. This review discusses risk factors and markers that predict the disease course and the occurrence of disease manifestations, with an emphasis on major organ involvement. In addition, risk factors will be described that are associated with mortality in SSc patients. The review addresses the impact of recent developments on screening, diagnosis and risk stratification as well as the need for further research where data are lacking.

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.

Novel Therapeutic Strategies for Reducing Right Heart Failure Associated Mortality in Fibrotic Lung Diseases

Fibrotic lung diseases carry a significant mortality burden worldwide. A large proportion of these deaths are due to right heart failure and pulmonary hypertension. Underlying contributory factors which appear to play a role in the mechanism of progression of right heart dysfunction include chronic hypoxia, defective calcium handling, hyperaldosteronism, pulmonary vascular alterations, cyclic strain of pressure and volume changes, elevation of circulating TGF-β, and elevated systemic NO levels. Specific therapies targeting pulmonary hypertension include calcium channel blockers, endothelin (ET-1) receptor antagonists, prostacyclin analogs, phosphodiesterase type 5 (PDE5) inhibitors, and rho-kinase (ROCK) inhibitors. Newer antifibrotic and anti-inflammatory agents may exert beneficial effects on heart failure in idiopathic pulmonary fibrosis. Furthermore, right ventricle-targeted therapies, aimed at mitigating the effects of functional right ventricular failure, include β-adrenoceptor (β-AR) blockers, angiotensin-converting enzyme (ACE) inhibitors, antioxidants, modulators of metabolism, and 5-hydroxytryptamine-2B (5-HT2B) receptor antagonists. Newer nonpharmacologic modalities for right ventricular support are increasingly being implemented. Early, effective, and individualized therapy may prevent overt right heart failure in fibrotic lung disease leading to improved outcomes and quality of life.

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.

Exercise-Induced Abnormal Increase of Systolic Pulmonary Artery Pressure in Adult Patients With Sickle Cell Anemia: An Exercise Stress Echocardiography Study

BACKGROUND

Pulmonary hypertension (PH) at rest is a risk factor for death in patients with sickle cell anemia (SCA). Exercise echocardiography (EE) can detect latent PH. We sought to investigate the occurrence of exercise-induced abnormal response of systolic pulmonary artery pressure (SPAP) in adult patients with SCA and normal SPAP at rest, and to identify the independent predictors of this abnormal response.

METHODS AND RESULTS

Forty-four adult patients with SCA and normal SPAP at rest (tricuspid regurgitant jet flow velocity [TRV] <2.5 m/sec) were studied and divided into 2 groups: exhibiting normal SPAP after treadmill EE (TRV ≤ 2.7 m/sec) (G1), and exhibiting abnormal exercise-induced increase of SPAP (TRV > 2.7 m/sec) (G2). TRV cutoff points at rest and during EE were based on data from healthy-matched control subjects. Abnormal response of SPAP with exercise occurred in 57% of the sample (G2), with mean TRV level of 3.39 ± 0.41 m/sec (range 2.8-4.5 m/sec), significantly higher than those of G1 (2.29 ± 0.25 m/sec, range 2.0-2.7 m/sec; P < 0.001). Multivariate analysis identified TRV value in resting conditions ≥2.25 m/sec (P < 0.05), left atrial volume index ≥41 mL/m² (P < 0.05), and a E/e'-waves ratio ≥6.3 (P < 0.05) as independent predictors of exercise-induced increase of SPAP.

CONCLUSION

We concluded that adult patients with SCA and normal SPAP at rest may exhibit abnormal exercise-induced increase in SPAP, which was independently related to resting TRV levels, and indices of diastolic impairment and left ventricular filling pressure.

Pulmonary arterial hypertension: the key role of echocardiography

Echocardiography is a key screening tool in the diagnostic algorithm of pulmonary arterial hypertension (PAH). It provides an estimate of right ventricular function and pulmonary artery pressure, either at rest or during exercise, and is useful in ruling out secondary causes of pulmonary hypertension (PH) such as left heart disease or congenital heart disease. Several studies have showed that echocardiography is insufficiently precise as single tool for the ultimate diagnosis of PH respect to the right heart catheterization, considered the gold standard technique. Echocardiography is valuable in assessing prognosis and treatment options, monitoring the efficacy of specific therapeutic interventions, and detecting the preclinical stages of disease. The ideal imaging modality for accurate noninvasive assessment of the right heart should be accurate and precise, not influenced by loading conditions, routinely practicable and easily repeatable. For all such reasons and considering that PAH is a rare and severe condition, a complete noninvasive assessment of right heart function requires a deep knowledge of the disease and a multimodality approach.

Imaging in pulmonary hypertension: Focus on the role of echocardiography

Patients with pulmonary hypertension must be evaluated using a multimodality approach to ensure a correct diagnosis and basal evaluation as well as a prognostic assessment. Beyond the assessment of pulmonary pressures, the echocardiographical examination allows the evaluation of right ventricular adaptation to elevated afterload. Numbers of variables are commonly used in the assessment of the pulmonary hypertension patient in order to detect changes in right heart geometry, right-to-left interaction and right ventricular dysfunction. Whereas an isolated change in one echocardiographical variable is not meaningful, multiple echocardiographical variable modifications together provide accurate information. In this review, we will link pulmonary hypertension pathophysiological changes with echocardiographical indices and describe the clinical implications of echocardiographical findings.

Determinants of exercise-induced pulmonary arterial hypertension in systemic sclerosis

BACKGROUND

Exercise-induced pulmonary arterial hypertension (EIPH) in systemic sclerosis (SSc) has already been observed but its determinants remain unclear. The aim of this study was to determine the incidence and the determinants of EIPH in SSc.

METHODS AND RESULTS

We prospectively enrolled 63 patients with SSc (age 54±3years, 76% female) followed in CHU Sart-Tilman in Liège. All patients underwent graded semi-supine exercise echocardiography. Systolic pulmonary arterial pressure (sPAP) was derived from the peak velocity of the tricuspid regurgitation jet and adding the estimation of right atrial pressure, both at rest and during exercise. Resting pulmonary arterial hypertension (PH) was defined as sPAP > 35 mmHg and EIPH as sPAP > 50 mmHg during exercise. The following formulas were used: mean PAP (mPAP) = 0.61 × sPAP + 2, left atrial pressure (LAP)=1.9+1.24 × left ventricular (LV) E/e' and pulmonary vascular resistance (PVR)=(mPAP-LAP)/LV cardiac output (CO) and slope of mPAP-LVCO relationship=changes in mPAP/changes in LVCO. Resting PH was present in 3 patients (7%) and 21 patients developed EIPH (47%). Patients with EIPH had higher resting LAP (10.3 ± 2.2 versus 8.8 ± 2.3 mmHg; p = 0.03), resting PVR (2.6 ± 0.8 vs. 1.4 ± 1.1 Woods units; p=0.004), exercise LAP (13.3 ± 2.3 vs. 9 ± 1.7 mmHg; p < 0.0001), exercise PVR (3.6 ± 0.7 vs. 2.1 ± 0.9 Woods units; p = 0.02) and slope of mPAP-LVCO (5.8 ± 2.4 vs. 2.9 ± 2.1 mmHg/L/min; p < 0.0001). After adjustment for age and gender, exercise LAP (β=3.1 ± 0.8; p=0.001) and exercise PVR (β=7.9 ± 1.7; p=0.0001) were independent determinants of exercise sPAP.

CONCLUSION

EIPH is frequent in SSc patients and is mainly related to both increased exercise LV filling pressure and exercise PVR.

Systemic sclerosis-associated pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is the leading cause of death in systemic sclerosis (SSc) and affects up to 12% of all patients with SSc, with a 50% mortality rate within 3 years of PAH diagnosis. Compared with the idiopathic form of PAH (IPAH), patients with SSc-associated PAH (SSc-PAH) have a threefold increased risk of death and may receive a diagnosis late in the course of disease because of insidious onset and the high prevalence of cardiac, musculoskeletal, and pulmonary parenchymal comorbidities. Treatment with conventional forms of PAH therapy often yield poor results compared with IPAH cohorts; unfortunately, the exact reasons behind this remain poorly understood but likely include variations in the pathologic mechanisms, differences in cardiovascular response to increasing afterload, and inadequate strategies to detect and treat SSc-PAH early in its course. Current methods for screening and longitudinal evaluation of SSc-PAH, such as the 6-min walk test, transthoracic echocardiography, and MRI, each have notable advantages and disadvantages. We provide an up-to-date, focused review of SSc-PAH and how it differs from IPAH, including pathogenesis, appropriate screening for disease onset, and new approaches to treatment and longitudinal assessment of this disease.

Stress Doppler echocardiography in systemic sclerosis: evidence for a role in the prediction of pulmonary hypertension

OBJECTIVE

Patients with systemic sclerosis (SSc) in whom pulmonary hypertension (PH) is not suspected have been reported to develop an inappropriate increase of pulmonary artery systolic pressure as estimated by Doppler echocardiography under conditions of exercise (pulmonary artery systolic pressure under exercise). We undertook this study to investigate whether this increase or any other parameter detectable by stress Doppler echocardiography has utility in predicting the development of PH in SSc.

METHODS

We enrolled a total of 170 patients with SSc previously investigated using standard and stress Doppler echocardiography and tissue Doppler imaging. Each patient was evaluated at baseline and yearly for skin and internal organ involvement. Right-sided heart catheterization was carried out when PH was suspected. The baseline Cochin Risk Prediction Score was calculated retrospectively.

RESULTS

During followup, 6 patients (3.5%) developed PH. Compared with patients without any feature suggesting PH, the Cochin Risk Prediction Score was higher in this group (mean ± SD 4.2 ± 0.9 versus 3.4 ± 0.9; P < 0.05), as was the difference between pulmonary artery systolic pressure under exercise and pulmonary artery systolic pressure (Δpulmonary artery systolic pressure) (18.2 ± 7 mm Hg versus 9.4 ± 6.5 mm Hg; P < 0.001), even when adjusted for cardiac index changes. In multivariate analysis, Δpulmonary artery systolic pressure (hazard ratio [HR] 3.4 [95% confidence interval 1.4-8], P < 0.01) and Cochin Risk Prediction Score within the fifth quintile of the values registered in our series (HR 9.3 [95% confidence interval 1.4-63.7], P < 0.05) were the only factors independently predictive of PH during followup. A Δpulmonary artery systolic pressure cutoff of >18 mm Hg, identified by receiver operating characteristic curve analysis, had a sensitivity of 50% and a specificity of 90% for the development of PH during followup.

CONCLUSION

An inappropriate response to exercise among patients with SSC is detectable by stress Doppler echocardiography. Independently of other clinical associations, increased Δpulmonary artery systolic pressure heralds PH. Stress Doppler echocardiography may represent an additional screening tool for this severe complication.

Exercise capacity in relation to autoantibodies in systemic sclerosis patients

Autoantibodies have been detected in systemic sclerosis patients, and typical clinical features regarding organ involvement by each autoantibody have been reported. To reveal differences in exercise intolerance in patients with either anti-topoisomerase-I or anti-centromere antibodies, 53 systemic sclerosis patients were investigated retrospectively. A 6-min walking distance showed no significant differences (P = 0.090) between autoantibodies, while exercise-induced hypoxia during the 6-min walking test was significant in subjects with the anti-topoisomerase-I antibody (P = 0.033). The percent predicted of vital capacity, the diffusion capacity of the lung for carbon monoxide, and the modified Rodnan skin score were affected more in subjects with the anti-topoisomerase-I antibody than the anti-centromere antibody. The main parameter affecting the 6-min walking distance was the percent predicted of vital capacity for each autoantibody, and there was a significant positive relationship for all subjects (R² = 0.30, P < 0.0001). Exercise-induced hypoxia was also shown in the more affected subjects in the percent predicted of vital capacity and the diffusion capacity of the lung for carbon monoxide. Lung parameters were suggested to be more important factors determining exercise intolerance and induced hypoxia than detected autoantibodies.

Exaggerated increase of exercise-induced pulmonary artery pressure in systemic sclerosis patients predominantly results from left ventricular diastolic dysfunction

OBJECTIVE

High prevalence of exaggerated pulmonary artery pressure response to exercise (EPAPR) was reported in patients with systemic sclerosis (SSc). However, pathophysiology of this phenomenon has not been well defined. Therefore, we evaluated the frequency and potential aetiology of EPAPR in SSc patients.

METHODS

We included 85 patients (79 female, 6 male, mean age 54.3 ± 13.9 years) with SSc. Transthoracic echocardiography followed by exercise Doppler echocardiography (EDE) were performed. A positive EDE was defined when at least 20 mmHg increase of tricuspid regurgitation peak gradient (TRPG) was recorded. Right heart catheterization (RHC) with exercise was performed in positive EDE patients and in subjects with resting TRPG >31 mmHg.

RESULTS

Resting TRPG >31 mmHg and/or positive EDE was found in 30 patients and they were referred to RHC. Finally, RHC was performed in 20 patients (16 pts resting TRPG >31 mmHg and 4 others normal resting TRPG and positive EDE). In 12 (60 %) of them an EPAPR with elevated pulmonary capillary wedge pressure (PCWP) was observed. Interestingly, mean left atrium (LA) diameter was greater in an EPAPR with elevated PCWP patients than in subjects with normal exercise response (39.36 ± 5.6 vs. 35.53 ± 3.48, p = 0.03). In EPAPR with elevated PCWP group greater mean value of E/E' of mitral lateral annulus was observed (7.98 ± 3.35 vs. 6.27 ± 1.94, p = 0.03). In the univariate logistic regression analysis increased LA diameter was significant predictor of EPAPR with elevated PCWP (OR 1.199, 95 % CI 1.029-1.396, p = 0.019).

CONCLUSIONS

Despite very well-known risk of PAH in systemic sclerosis patients, the excessive increase of PAP during exercise is more commonly caused by left ventricular diastolic dysfunction than pulmonary arterial vasculopathy.

Clinical and echocardiographic correlations of exercise-induced pulmonary hypertension in systemic sclerosis: a multicenter study

BACKGROUND

Patients with systemic sclerosis (SSc) are at risk for developing pulmonary hypertension, which is associated with a poor prognosis. Exercise Doppler echocardiography enables the identification of exercise-induced increase in pulmonary artery systolic pressure (PASP) and may provide a thorough noninvasive hemodynamic evaluation.

AIM

The aim of this study was to evaluate the clinical and echocardiographic determinants of exercise-induced increase in PASP in a large population of patients with SSc.

METHODS

We selected 164 patients with SSc (age 58 ± 13 years, 91% female) with normal resting PASP (<40 mm Hg) who underwent a comprehensive 2-dimensional and Doppler echocardiography and graded bicycle semisupine exercise Doppler echocardiography. Pulmonary artery systolic pressure, cardiac output, and pulmonary vascular resistance (PVR) were estimated noninvasively. Cutoff values of PASP ≥50 mm Hg and PVR ≥3.0 Wood Units at peak exercise were considered a significant exercise-induced increase in PASP and PVR, respectively.

RESULTS

Sixty-nine (42%) patients showed a significant exercise-induced increase in PASP. Among them, peak PVR ≥3 Wood Units was present only in 11% of patients, about 5% of the total population. Univariate analysis showed that age, presence of interstitial lung disease, and both right and left diastolic dysfunction are predictors of peak PASP ≥50 mm Hg, but none of these parameters predict elevated peak PVR.

CONCLUSIONS

Exercise-induced increase in PASP occurs in almost one-half of patients with SSc with normal resting PASP. Peak exercise PASP is affected by age, interstitial lung disease, and right and left ventricular diastolic dysfunction and, only in 5% of the patients, is associated with an increase in PVR during exercise, suggesting heterogeneity of the mechanisms underlying exercise-induced pulmonary hypertension in SSc.

Echocardiography in pulmonary arterial hypertension: from diagnosis to prognosis

Pulmonary arterial hypertension is most often diagnosed in its advanced stages because of the nonspecific nature of early symptoms and signs. Although clinical assessment is essential when evaluating patients with suspected pulmonary arterial hypertension, echocardiography is a key screening tool in the diagnostic algorithm. It provides an estimate of pulmonary artery pressure, either at rest or during exercise, and is useful in ruling out secondary causes of pulmonary hypertension. In addition, echocardiography is valuable in assessing prognosis and treatment options, monitoring the efficacy of specific therapeutic interventions, and detecting the preclinical stages of disease.