Effects of exercise training on pulmonary hemodynamics, functional capacity and inflammation in pulmonary hypertension

Effect of home-based pulmonary rehabilitation on exercise capacity in post COVID-19 patients: a randomized controlled trail

BACKGROUND

Coronavirus 2019 (COVID-19) is an epidemic condition that compromises various consequences. The goal of this study was to investigate the effect of home-based pulmonary rehabilitation on exercise capacity in patients with post COVID-19 syndrome.

METHODS

The study was designed as a randomized control trial. A total of sixty-eight patients with post COVID-19 syndrome complaining of fatigue, dyspnea, and exercise intolerance participated in this study. Their ages ranged from 40 to 70 years old. The patients were randomly classified into two equal groups. The control group received usual medical care only, whereas the rehabilitation group received a selected home-based pulmonary rehabilitation exercise program plus the same usual medical care. The Physical Fitness Index (PFI), Chalder fatigue index, SF-36 questionnaire, dyspnea scale, and six-minute walk test (6 MWT) were measured before and after 12 weeks of intervention.

RESULTS

The rehabilitation group showed a significant lower mean of Chalder fatigue (11.1 ± 0.94) and a higher mean of 6MWT (439.7 ± 25.3) and PFI (52.3 ± 10.2), in addition to a higher mean of the SF-36 Questionnaire (66.4 ± 3.7) and a significant improvement of dyspnea in the mMRC score (26.7%), grade 2, (63.3%), grade 1 (10%), and grade 0 with a p-value < 0.001 when compared to the control group.

CONCLUSION

Home-based pulmonary rehabilitation (HBPR) for patients with post COVID-19 syndrome is effective and has a potential direct influence on exercise capacity, fatigue, dyspnea, and quality of life. HBPR could be considered an adjunctive, applicable, and low-cost therapy for patients with post COVID-19 syndrome.

TRIAL REGISTRATION

The study was registered in Pan African Clinical Trial Registry as a clinical trial ID (PACTR202111640499636), November 2021.

Exercise Effects on Health-Related Quality of Life (HRQOL), Muscular Function, Cardiorespiratory Function, and Body Composition in Smokers: A Narrative Review

Smoking is amongst the leading global threats with high incidences of preventable premature mortality, morbidity, and various chronic diseases. The World Health Organization (WHO) proclaims a decrease in the prevalence of daily smoking in both males and females from 1980 to 2012, however, the number of regular smokers since then has exponentially increased. The low socio-income status individuals contribute greatly towards tobacco-attributable diseases due to limited access to healthcare systems, mostly in developing countries as compared to developed countries. Smoking affects the optimal functioning of the human body, which results in altered body system processes. Although a high intake of nicotine can lead to prolonged adherence and dependence on smoking, other factors, such as an individual's level of health-related quality of life (HRQOL), stress, depression, and anxiety, can produce similar effects. Smoking has a wide impact on lifestyle factors, which explains the increase in the number of sedentary smokers with decreased health fitness levels and poor lifestyle conditions. Therefore, this study seeks to investigate the exercise effects on health-related quality of life (HRQOL), muscular function, cardiorespiratory function, and body composition in smokers. Concurrently, exercise as an intervention has been sourced as a rehabilitation strategy during smoking cessation programmes to restore the diminishing health components, however, a high rate of relapse occurs due to intolerable withdrawal symptoms.

Effectiveness and safety of inspiratory muscle training in patients with pulmonary hypertension: A systematic review and meta-analysis

BACKGROUND

Inspiratory muscle training (IMT) is a simple and well-tolerated physical therapy that increases respiratory muscle strength and relieving the degree of dyspnea and fatigue. Therefore, it may be used as a transitional modality before exercise training or as a specific physical therapy intervention for those who are diagnosed with respiratory muscle weakness. However, the current evidence on IMT in pulmonary hypertension (PH) patients is inconclusive. The purpose of this systematic review and meta-analysis was to summarize the current role of IMT in this group of patients.

METHODS

PubMed, EMBASE, and Cochrane databases were searched through May 2022. Trials examining the feasibility and effectiveness of IMT in PH patients. Outcome measures included adverse events, training adherence and compliance, maximum inspiratory pressure (MIP), maximum expiratory pressure (MEP), forced vital capacity (FVC%), forced expiratory volume in 1 s (FEV1%), FEV1/FVC%, 6 min walk distance (6MWD), Peak VO2, dyspnea, and fatigue perception after the IMT training program. Only randomized controlled trials were included. The Cochrane Risk of Bias tool for controlled trials was adopted to assess study quality. Statistical heterogeneity was evaluated with the chi-square test and I 2 statistic. Mean differences and 95% confidence intervals (CIs) were estimated.

RESULTS

We ultimately identified four studies that met the criteria. These studies comprised 80 patients with 16 males and 64 females. The mean age was 53.25. The main types of PH were group I (pulmonary arterial hypertension, 95%) and group IV (chronic thromboembolic PH, 5%). No severe adverse events were reported in the included studies. IMT had a significant effect on improving MIP (18.89 cmH2O; 95% CI: 9.43-28.35, P < 0.001) and MEP (8.06 cmH2O; 95% CI: 2.39-13.73; P = 0.005), increase in the 6MWD (30.16 m; 95% CI: 1.53-58.79; P = 0.04). No significant improvement was found in pulmonary function (P > 0.05), and uncertain effect on the quality of life (QoL) score.

CONCLUSION

Based on currently limited evidence, IMT is an effective physical therapy for increasing respiratory muscle function and exercise capacity, but still a lack of evidence on dyspnea and fatigue levels, pulmonary function, and QoL in PH patients. There are reasons to believe that IMT is a promising intervention in PH patients, enriching rehabilitation options and serving as a bridge before formal exercise training. It is expected that IMT will play an important role in the future clinical pathway of physical therapy for this group of patients.

SYSTEMATIC REVIEW REGISTRATION

[https://www.crd.york.ac.uk/PROSPERO/logout.php], identifier [CRD42022335972].

Exercise Training as a Non-Pharmacological Therapy for Patients with Pulmonary Arterial Hypertension: Home-Based Rehabilitation Program and Training Recommendations

Pulmonary arterial hypertension (PAH) is a chronic and progressive disorder with a poor prognosis associated with non-specific symptoms, including general weakness, shortness of breath on exertion, and decreased muscle strength and endurance. Despite recent significant progress in the field of PAH therapy, many patients are still characterized by a dynamic course of the disease, a significant reduction in physical performance, a constantly deteriorating quality of life, and limited activity in everyday life. Thus, the main goal of PAH therapy is to ensure an acceptable level of quality of life as early as possible in the course of the disease, reduce the progression of symptoms and, if possible, improve the prognosis, which is still poor. The perception of the importance of activity and exercise has changed significantly in recent years, and rehabilitation dedicated to PAH patients is now considered to be one of the new adjuvant treatment options. Currently, there is insufficient data on what form, frequency, and intensity of exercise are required for the best results. Nevertheless, exercise training (ET) is necessary in order to reverse the accompanying PAH impairment of exercise capacity and, without additional clinical risk, to maximize the benefits of pharmacotherapy. This review summarizes the current state of knowledge on the rehabilitation of PAH patients and presents the available rehabilitation models. In addition, it includes a ready-to-use, illustrated, safe home rehabilitation program with recommendations for its use. Utilizing ET as an adjuvant treatment option to improve the functional capacity and quality of life of patients may enhance the clinical effectiveness of therapeutic management and contribute to the improvement of the quality of care for patients suffering from PAH. The beneficial effect of exercise training on the development of symptoms improves the clinical course of the disease, and a lower incidence of adverse events can lead to a reduction in health care expenditure.

Effect of Ground-Based Walk Training in Pulmonary Hypertension

This study aimed to determine the effect of ground-based walking training on exercise capacity, physical activity, quadriceps muscle strength, and quality of life (QoL) in patients with pulmonary hypertension. A total of 24 patients were included in the study. Patients were randomly assigned to 2 groups as the walking group or the control group. The walking group participated in 30-minute supervised ground-based walking training 2 days/week for 8 weeks. Also, they walked unsupervised at least 1 day/week. The control group received no intervention. The number of weekly steps taken in both groups was recorded using a pedometer. In addition to the sociodemographic and clinic characteristics of the patients, the endurance shuttle walk test, incremental shuttle walk test, and 6-minute walk test were used for the evaluation of exercise capacity, and an activity monitor and pedometer for physical activity, a dynamometer for quadriceps muscle strength, and emPHasis-10 for QoL. After 8 weeks, endurance capacity, maximal exercise capacity, and the number of steps significantly improved in the walking group (p <0.05). The 6-minute walk distance, physical activity, quadriceps muscle strength, and QoL were similar in both groups (p >0.05). The results of the study showed that ground-based walking could improve endurance capacity, maximal exercise capacity, and the number of steps. Quadriceps muscle strength also improved in the walking group. No adverse effects were reported during the training period. Ground-based walking training can be performed safely in patients with pulmonary hypertension.

Optimal aerobic exercise intensity and its influence on the effectiveness of exercise therapy in patients with pulmonary arterial hypertension: a systematic review

Background

Exercise intensity in exercise training programs is an important determinant of program efficacy, such as improvement in exercise capacity and quality of life (QOL). It is not well known whether differently applied exercise intensities are efficacious when used in exercise-based cardiac rehabilitation programs for patients with pulmonary arterial hypertension (PAH).

Methods

Three databases (PubMed, EMBASE, and CINAHL) were searched with the following inclusion criteria: comparative study of exercise interventions for patients with pulmonary arterial hypertension. Three clinical specialists (a physician, nurse, and exercise physiologist) selected the included articles using the process of systematic review. Included articles were grouped according to aerobic exercise intensity: low, moderate-to-vigorous, and vigorous. The level of evidence for each study was rated using Sackett’s levels of evidence.

Results

Of 1,452 studies reviewed, 8 were included according to the inclusion criteria (3 randomized controlled trials (RCTs), 3 prospective studies, and 2 case series). Exercise capacity for a six-minute walk distance (mean: 57.7 m) and QOL improved in the above moderate intensity group, while the low intensity group did not show improvement after intervention. For termination criteria, data obtained from the reviewed articles were not sufficient to suggest any exercise intensity recommendations for patients with pulmonary arterial hypertension.

Discussion

The findings in this study suggest that at least moderate aerobic exercise intensity is needed to significantly improve six-minute walk distance and QOL in individuals diagnosed with World Health Organization Group 1 of pulmonary arterial hypertension. There is a need for prospective RCTs comparing different exercise intensities in this patient population.

Exercise intolerance in pulmonary arterial hypertension: insight into central and peripheral pathophysiological mechanisms

Exercise intolerance is a cardinal symptom of pulmonary arterial hypertension (PAH) and strongly impacts patients' quality of life (QoL). Although central cardiopulmonary impairments limit peak oxygen consumption (V' O2peak ) in patients with PAH, several peripheral abnormalities have been described over the recent decade as key determinants in exercise intolerance, including impaired skeletal muscle (SKM) morphology, convective O2 transport, capillarity and metabolism indicating that peripheral abnormalities play a greater role in limiting exercise capacity than previously thought. More recently, cerebrovascular alterations potentially contributing to exercise intolerance in patients with PAH were also documented. Currently, only cardiopulmonary rehabilitation has been shown to efficiently improve the peripheral components of exercise intolerance in patients with PAH. However, more extensive studies are needed to identify targeted interventions that would ultimately improve patients' exercise tolerance and QoL. The present review offers a broad and comprehensive analysis of the present literature about the complex mechanisms and their interactions limiting exercise in patients and suggests several gaps in knowledge that need to be addressed in the future for a better understanding of exercise intolerance in patients with PAH.

Benefícios do exercício físico na hipertensão arterial pulmonar associada à cardiopatia congênita não corrigida

Introdução: as cardiopatias congênitas são classificadas como um dos principais grupos para desenvolver hipertensão arterial pulmonar. O programa de exercício físico pode auxiliar no aumento da capacidade de vida diária, melhora clínica e funcional, minimizando as consequências deletérias da patologia.Relato do caso: reportamos um caso de um paciente do gênero masculino, 31 anos, com diagnóstico clínico de hipertensão arterial pulmonar grave em decorrência da dupla via de saída do ventrículo direito com comunicação interventricular, sem intervenção cirúrgica. Após ser encaminhado ao programa de Reabilitação Cardiopulmonar e Metabólica em um centro de referência em cardiologia do Rio Grande do Sul, foram realizadas avaliações clínicas e, também, da capacidade funcional pelo teste de caminhada de 6 minutos, da força muscular e resistência periférica, pelo teste Sentar-Levantar, e da força muscular respiratória, pelo exame de manovacuometria. Os valores apresentavam-se abaixo do valor previsto. O programa de exercício proposto foi realizado durante 30 sessões constando de exercícios aeróbicos com duração de 33 minutos, combinados ao treino de fortalecimento dos grandes grupos musculares.Conclusão: após o término do programa observou-se um acréscimo de 83 metros no teste de caminhada de 6 minutos e um aumento da força muscular respiratória, assim como, redução redução nos parâmetros da escala de Borg.

Benefícios do exercício físico na hipertensão arterial pulmonar associada à cardiopatia congênita não corrigida

Introdução: as cardiopatias congênitas são classificadas como um dos principais grupos para desenvolver hipertensão arterial pulmonar. O programa de exercício físico pode auxiliar no aumento da capacidade de vida diária, melhora clínica e funcional, minimizando as consequências deletérias da patologia.Relato do caso: reportamos um caso de um paciente do gênero masculino, 31 anos, com diagnóstico clínico de hipertensão arterial pulmonar grave em decorrência da dupla via de saída do ventrículo direito com comunicação interventricular, sem intervenção cirúrgica. Após ser encaminhado ao programa de Reabilitação Cardiopulmonar e Metabólica em um centro de referência em cardiologia do Rio Grande do Sul, foram realizadas avaliações clínicas e, também, da capacidade funcional pelo teste de caminhada de 6 minutos, da força muscular e resistência periférica, pelo teste Sentar-Levantar, e da força muscular respiratória, pelo exame de manovacuometria. Os valores apresentavam-se abaixo do valor previsto. O programa de exercício proposto foi realizado durante 30 sessões constando de exercícios aeróbicos com duração de 33 minutos, combinados ao treino de fortalecimento dos grandes grupos musculares.Conclusão: após o término do programa observou-se um acréscimo de 83 metros no teste de caminhada de 6 minutos e um aumento da força muscular respiratória, assim como, redução redução nos parâmetros da escala de Borg.

Vital capacity and valvular dysfunction could serve as non-invasive predictors to screen for exercise pulmonary hypertension in the elderly based on a new diagnostic score

Introduction: Exercise pulmonary hypertension (exPH) has been defined as total pulmonary resistance (TPR) >3 mm Hg/L/min and mean pulmonary artery pressure (mPAP) >30 mm Hg, albeit with a considerable risk of false positives in elderly patients with lower cardiac output during exercise.

Methods: We retrospectively analysed patients with unclear dyspnea receiving right heart catheterisation at rest and exercise (n=244) between January 2015 and January 2020. Lung function testing, blood gas analysis, and echocardiography were performed. We elaborated a combinatorial score to advance the current definition of exPH in an elderly population (mean age 67.0 years±11.9). A stepwise regression model was calculated to non-invasively predict exPH.

Results: Analysis of variables across the achieved peak power allowed the creation of a model for defining exPH, where three out of four criteria needed to be fulfilled: Peak power ≤100 Watt, pulmonary capillary wedge pressure ≥18 mm Hg, pulmonary vascular resistance >3 Wood Units, and mPAP ≥35 mm Hg. The new scoring model resulted in a lower number of exPH diagnoses than the current suggestion (63.1% vs. 78.3%). We present a combinatorial model with vital capacity (VC_max) and valvular dysfunction to predict exPH (sensitivity 93.2%; specificity 44.2%, area under the curve 0.73) based on our suggested criteria. The odds of the presence of exPH were 2.1 for a 1 l loss in VC_max and 3.6 for having valvular dysfunction.

Conclusion: We advance a revised definition of exPH in elderly patients in order to overcome current limitations. We establish a new non-invasive approach to predict exPH by assessing VC_max and valvular dysfunction for early risk stratification in elderly patients.

Exercise Program Improves Functional Capacity and Quality of Life in Uncorrected Atrial Septal Defect-Associated Pulmonary Arterial Hypertension: A Randomized-Control Pilot Study

OBJECTIVE

To assess the effect of combined hospital and home-based exercise programs on functional capacity and quality of life (QoL) among uncorrected atrial septal defect-associated pulmonary arterial hypertension (ASD-PAH) patients.

METHODS

This study was a randomized controlled trial with uncorrected ASD-PAH patients as the subjects. They were allocated randomly into control and exercise groups. Exercise group subjects performed hospital and home-based exercise programs, completing baseline 6-minute walking test (6MWT) and EQ-5D-3L QoL test (Utility Index and EQ-VAS scores), and were followed up for 12 weeks. The primary outcomes were 6MWT distance and EQ-5D-3L score at week 12. The N-terminal pro B-type natriuretic peptide (NT-proBNP) level was also assessed. A repeated-measure ANOVA was performed to detect endpoint differences over time.

RESULTS

The exercise group contained 20 subjects and control group contained 19. In total, 19 exercise group subjects and 16 control group subjects completed the protocol. The 6MWT distance, Utility Index score, and EQ-VAS score incrementally improved significantly in the exercise group from baseline until week 12, with mean differences of 76.7 m (p<0.001), 0.137 (p<0.001) and 15.5 (p<0.001), respectively. Compared with the control group, the exercise group had significantly increased 6MWT distance and utility index score at week 12. The EQ-VAS score increased in the exercise group at week 12. The NT-proBNP level decreased at week 12 in the exercise group.

CONCLUSION

Combined hospital and home-based exercise program added to PAH-targeted therapy, improving functional capacity and QoL in uncorrected ASD-PAH patients.

Exercise intolerance establishment in pulmonary hypertension: Preventive effect of aerobic exercise training

AIMS

1) Characterize the progression of exercise intolerance in monocrotaline-induced pulmonary hypertension (PH) in mice and 2) evaluate the therapeutic effect of aerobic exercise training (AET) on counteracting skeletal and cardiac dysfunction in PH.

MAIN METHODS

Wild type C57BL6/J mice were studied in two different time points: 2 months and 4 months. Exercise tolerance was evaluated by graded treadmill exercise test. The AET was performed in the last month of treatment of 4 months' time point. Cardiac function was evaluated by echocardiography. Skeletal muscle cross-sectional area was assessed by immunofluorescence. The diameter of cardiomyocytes and pulmonary edema were quantified by staining with hematoxylin-eosin. The variables were compared among the groups by two-way ANOVA or non-paired Student's t-test. Significance level was set at p < 0.05.

KEY FINDINGS

After 2 months of MCT treatment, mice presented pulmonary edema, right cardiac dysfunction and left ventricle hypertrophy. After 4 months of MCT treatment, mice showed pulmonary edema, right and left cardiac dysfunction and remodeling associated with exercise intolerance and skeletal muscle atrophy. AET was able to reverse cardiac left ventricle dysfunction and remodeling, prevent exercise intolerance and skeletal muscle dysfunction. Thus, our data provide evidence of skeletal muscle abnormalities on advanced PH. AET was efficient in inducing an anti-cardiac remodeling effect besides preventing exercise intolerance.

SIGNIFICANCE

Our study provides a robust model of PH in mice, as well as highlights the importance of AET as a preventive strategy for exercise intolerance and, skeletal and cardiac muscle abnormalities in PH.

Effects of Different Types of Exercise Training on Pulmonary Arterial Hypertension: A Systematic Review

Pulmonary arterial hypertension (PAH) represents a chronic progressive disease characterized by high blood pressure in the pulmonary arteries leading to right heart failure. The disease has been a focus of medical research for many years due to its worse prognosis and limited treatment options. The aim of this study was to systematically assess the effects of different types of exercise interventions on PAH. Electronic databases were searched until July 2019. MEDLINE database was used as the predominant source for this paper. Studies with regards to chronic physical activity in adult PAH patients are compared on retrieving evidence on cellular, physiological, and psychological alterations in the PAH setting. Twenty human studies and 12 rat trials were identified. Amongst all studies, a total of 628 human subjects and 614 rats were examined. Regular physical activity affects the production of nitric oxygen and attenuates right ventricular hypertrophy. A combination of aerobic, anaerobic, and respiratory muscle training induces the strongest improvement in functional capacity indicated by an increase of 6 MWD and VO₂peak. In human studies, an increase of quality of life was found. Exercise training has an overall positive effect on the physiological and psychological components of PAH. Consequently, PAH patients should be encouraged to take part in regular exercise training programs.

Impact of Nutrition on Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is characterized by sustained vasoconstriction, vascular remodeling, inflammation, and in situ thrombosis. Although there have been important advances in the knowledge of the pathophysiology of PAH, it remains a debilitating, limiting, and rapidly progressive disease. Vitamin D and iron deficiency are worldwide health problems of pandemic proportions. Notably, these nutritional alterations are largely more prevalent in PAH patients than in the general population and there are several pieces of evidence suggesting that they may trigger or aggravate disease progression. There are also several case reports associating scurvy, due to severe vitamin C deficiency, with PAH. Flavonoids such as quercetin, isoflavonoids such as genistein, and other dietary polyphenols including resveratrol slow the progression of the disease in animal models of PAH. Finally, the role of the gut microbiota and its interplay with the diet, host immune system, and energy metabolism is emerging in multiple cardiovascular diseases. The alteration of the gut microbiota has also been reported in animal models of PAH. It is thus possible that in the near future interventions targeting the nutritional status and the gut dysbiosis will improve the outcome of these patients.

Right ventricular function correlates of right atrial strain in pulmonary hypertension: a combined cardiac magnetic resonance and conductance catheter study

The functional relevance of right atrial (RA) function in pulmonary hypertension (PH) remains incompletely understood. The purpose of this study was to explore the correlation of cardiac magnetic resonance (CMR) feature tracking-derived RA phasic function with invasively measured pressure-volume (P-V) loop-derived right ventricular (RV) end-diastolic elastance ( Eed) and RV-arterial coupling [ratio of end-systolic elastance to arterial elastance ( Ees/ Ea)]. In 54 patients with severe PH, CMR was performed within 24 h of diagnostic right heart catheterization and P-V measurements. RA phasic function was assessed by CMR imaging of RA reservoir, passive, and active strain. The association of RA phasic function with indexes of RV function was evaluated by Spearman’s rank correlation and linear regression analyses. Median [interquartile range] RA reservoir strain, passive strain, and active strain were 19.5% [11.0–24.5], 7.0% [4.0–12.0], and 13.0% [7.0–18.5], respectively. Ees/ Ea was 0.73 [0.48–1.08], and Eed was 0.14 mmHg/mL [0.05–0.22]. RV diastolic impairment [RV end-diastolic pressure (EDP) and Eed] was correlated with RA phasic function, but Ea and Ees were not. In addition, RA phasic function was correlated with inferior vena cava diameter. In multivariate linear regression analysis, adjusting for key P-V loop indexes, Eed and EDP remained significantly associated with RA phasic function. We conclude that RA phasic function is altered in relation to impaired diastolic function of the chronically overloaded right ventricle and contributes to backward venous flow and systemic congestion. These results call for more attention to RA function in the management of patients with PH.

NEW & NOTEWORTHY There is growing awareness of the importance of the right atrial (RA)-right ventricular (RV) axis in pulmonary hypertension (PH). Our results uncover alterations in RA phasic function that are related to depressed RV lusitropic function and contribute to backward venous return and systemic congestion in chronic RV overload. Assessment of RA function should be part of the management and follow-up of patients with PH.

Interval aerobic exercise in individuals with advanced interstitial lung disease: a feasibility study

Background: Aerobic exercise is used in the rehabilitation setting in people with interstitial lung disease (ILD), however little is known about interval exercise as a training strategy. The aim of this study was to compare the cardiorespiratory responses and preferences of a single bout of interval exercise with continuous exercise in individuals with advanced ILD. Methods: Peak work (Wpeak) was obtained from a cardiopulmonary exercise test (CPET). The total volume of prescribed exercise was matched between a bout of interval cycling (alternating 30 seconds at 100% of Wpeak: 30 seconds total rest × 20 min) and continuous cycling (50% of Wpeak × 20 min). Results: Nine lung transplant candidates with ILD were included: 4 men; 62 (6) years; forced vital capacity (FVC) 60% of predicted; and all using supplemental oxygen. Eight (89%) participants reported a preference for interval exercise and one reported no preference (p = .01). One participant required two unintended breaks during continuous exercise. There were no large differences between interval and continuous exercise although some trends emerged. Interval exercise resulted in a lower peak heart rate (124 (12) vs. 132 (15), p = .04) and a trend toward less oxygen desaturation (drop of 8 (4)% vs. 11 (5)%, p = .05) and lower end-exercise Borg leg fatigue (3.8 (2) vs. 4.4 (2), p = .05). End-exercise dyspnea was similar between both exercise modes. Conclusions: Interval exercise was well tolerated and preferred by participants with advanced ILD.

Decrease in Cerebral Oxygen Saturation During the 6-Minute Walk Test in Pediatric Pulmonary Arterial Hypertension

This observational study aimed to investigate the relationship between regional cerebral oxygen saturation (rSO₂) during the 6-minute walk test (6-MWT) and the demographic/clinical features of patients with pulmonary arterial hypertension (PAH). Cerebral oxygenation was evaluated during the 6-MWT in 20 pediatric patients with PAH aged ≥ 7 years [13 male, 7 female; median age 12.25 (range 7-18) years]. In all patients, regional cerebral oxygen saturation    (rSO₂), arterial oxygen saturation (SpO₂), and heart rate (HR) were measured using near-infrared spectroscopy (NIRS) for 2 min before the test, during the 6-MWT test, and 2 min after the test. The relationship between the changes in rSO₂, heart rate, and SpO₂ values and clinical and laboratory features was compared statistically. The mean pulmonary arterial pressure (mPAP) was 77 (range 25-126) mmHg, and the median 6-minute walk distance (6-MWD) was 427.5 (300-570) m. The changes in rSO₂ measurements ranged between 3.41 and 21.8%, and 70% of the patients had a greater than 10% decrease in rSO₂ during the test compared with baseline. Eight patients showed a decrease in rSO₂ without SpO₂ changes. The present study demonstrated a significant decrease in cerebral oxygenation in pediatric patients with PAH during the 6-MWT. We hypothesized that using a combination of the 6-MWT and regional cerebral oxygenation monitoring in pediatric patients with PAH in order to evaluate exercise capacity, as a reflection of reduced daily activities, would provide more precise predictive values than the 6-MWT alone.

Barriers to physical activity in patients with pulmonary hypertension

Patients with pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) have low levels of physical activity (PA). Increased PA has health benefits including improved quality of life. This study aimed to identify patient-perceived barriers to PA that correlate with objectively measured PA in this population. We performed a cross-sectional survey of 40 patients with PAH and CTEPH. Participants rated how often 15 barriers interfere with being physically active on a 5-point Likert Scale. The primary outcome measure was PA quantified using the Fitbit Zip activity tracker for two weeks. The primary independent variables were the 15 barriers and a summary score (total average barriers). Separate multivariable linear regressions were performed to assess the association between the 15 barriers and the summary score and PA adjusting for age, sex, and PAH etiology. Of the participants, 85% (34/40) had valid step counts and were included. Of these 34, 85% (n = 29) were female and 91% (n = 31) had PAH. The median (interquartile range [IQR]) number of daily steps was 3913 (2309-6313). The barriers endorsed most strongly were lack of self-discipline, lack of energy, and lack of interest. In the multivariable analysis, a 1-unit increase in perceived lack of interest, lack of enjoyment, and lack of skills was associated with a significant decrease in step counts of -1414 steps (95% confidence interval [CI] = (-2580 - -248), -1458 steps (-2404 - -511), and -1533 steps (-2910 - -156), respectively. Counseling and interventions aimed at increasing PA in patients with PAH should address interest, enjoyment, and skill development.

Evaluation of Clinical Outcomes and Simultaneous Digital Tracking of Daily Physical Activity, Heart Rate, and Inhalation Behavior in Patients With Pulmonary Arterial Hypertension Treated With Inhaled Iloprost: Protocol for the Observational VENTASTEP Study

BACKGROUND

Pulmonary arterial hypertension (PAH)-a progressive, ultimately fatal disease-patients often experience dyspnea, which can limit their daily physical activities. Iloprost is an inhaled therapy for PAH that has shown efficacy in clinical trials. However, clinical trials in PAH have provided only limited data on daily physical activity. Digital monitoring of daily physical activity in PAH is therefore attracting growing interest. To fully understand a patient's response to treatment, monitoring of treatment adherence is also required. The Breelib nebulizer for administration of iloprost saves inhalation data, thus allowing digital monitoring of adherence.

OBJECTIVE

This study aims to perform parallel digital tracking of daily physical activity parameters, heart rate, and iloprost inhalation data in patients with PAH, before and after starting inhaled iloprost treatment. The primary objective is to investigate correlations between changes in digital measures of daily physical activity and traditional clinical measures. Secondary objectives are to assess iloprost inhalation behavior, the association between daily physical activity measures and time since last inhalation, changes in sleep quality and heart rate, the association of heart rate with daily physical activity measures and iloprost inhalation, and adverse events.

METHODS

VENTASTEP is a digital, prospective, observational, multicenter, single-arm cohort study of adults with PAH in Germany, starting inhaled iloprost treatment via the Breelib nebulizer, in addition to existing PAH therapy. The study comprises a baseline period without iloprost treatment (≤2 weeks) and an observation period with iloprost treatment (3 months±2 weeks). The Apple Watch Series 2 and iPhone 6s are used with a dedicated study app to continuously measure digital daily physical activity parameters and heart rate during the baseline and observation periods; the watch is also used with a 6-min walk distance (6MWD) app to measure digital 6MWD at baseline and the end-of-observation visit. Inhalation frequency, completeness, and duration are monitored digitally via the nebulizer and the BreeConnect app. Sleep quality is assessed using the Pittsburgh Sleep Quality Index at baseline and the end-of-observation visit. Changes in traditional outcome measures (6MWD, Borg dyspnea scale, EuroQol 5-dimensions questionnaire, functional class, and brain natriuretic peptide [BNP] or N-terminal proBNP) between baseline and the end-of-observation visit will be correlated with changes in digital daily physical activity parameters and digital 6MWD as the primary analysis.

RESULTS

The first participant was enrolled in February 2018 (estimated study completion by July 2019; planned sample size: 80 patients).

CONCLUSIONS

The VENTASTEP study will inform future research on the utility of digital parameters as outcome assessment tools for disease monitoring in PAH. The study will also provide insight into clinical outcomes, daily physical activity, and quality of life in patients adding inhaled iloprost, to existing PAH therapy.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03293407; https://clinicaltrials.gov/ct2/show/NCT03293407 (Archived by WebCite at http://www.webcitation.org/6ywPGcn4I).

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/12144.

Effects of exercise training on physical and psychosocial health in children with chronic respiratory disease: a systematic review and meta-analysis

INTRODUCTION

Chronic disease in children is increasing, including the prevalence of chronic respiratory diseases such as asthma, cystic fibrosis (CF), bronchiectasis and bronchopulmonary dysplasia (BPD). The aim of this systematic review and meta-analysis was to evaluate the effects of exercise training on health outcomes in children with chronic respiratory disease.

METHOD

Five databases were searched for randomised controlled trials investigating the effects of exercise training on children with chronic respiratory disease. Following the PRISMA guidelines, eligible studies were identified and data were extracted. A meta-analysis was conducted for the outcomes cardiovascular fitness, lung function and quality of life (QoL).

RESULTS

The initial search returned 3688 papers. Twenty-seven (17 in children with asthma, 10 in children with CF) were included in the systematic review and 24 of these were included in the meta-analysis. No studies were identified in children with bronchiectasis or BPD. Included papers had a total of 1009 participants aged 8-20 years. In addition to cardiovascular fitness, lung function and QoL, studies also assessed pulmonary function, respiratory muscle strength, muscular strength and inflammation. Meta-analysis showed a large significant effect size in favour of exercise for cardiovascular fitness (peak VO2) (standard mean difference (SMD)=1.16, 95%  CI 0.61 to 1.70) and QoL (SMD=1.27, 95% CI 0.72 to 1.82) as well as a small, non-significant effect size for lung function (FEV1) (SMD=0.02, 95% CI -0.38 to 0.42).

CONCLUSION

Exercise training significantly improves cardiovascular fitness and QoL in children with asthma and CF. Further research is needed, particularly in children with bronchiectasis and BPD.

Circulating MicroRNA Markers for Pulmonary Hypertension in Supervised Exercise Intervention and Nightly Oxygen Intervention

Rationale: Therapeutic exercise training has been shown to significantly improve pulmonary hypertension (PH), including 6-min walking distance and right heart function. Supplemental nightly oxygen also has therapeutic effects. A biomarker tool that could query critical gene networks would aid in understanding the molecular effects of the interventions.

Methods: Paired bio-banked serum (n = 31) or plasma (n = 21) samples from the exercise or oxygen intervention studies, respectively, and bio-banked plasma samples (n = 20) from high altitude induced PH in cattle were tested. MicroRNAs (miRNAs) markers were chosen for study because they regulate gene expression, control the function of specific gene networks, and are conserved across species.

Results: miRNAs that control muscle (miR-22-3p, miR-21-5p) or erythrocyte function (miR-451a) were chosen based on pilot experiments. Plasma samples from cattle that developed PH in high altitude had significantly higher miR-22-3p/(relative to) miR-451a values when compared to control cattle tolerant to high altitude. Measurements of miR-22-3p/miR-451a values in serum from patients receiving exercise training showed that the values were significantly decreased in 74.2% of the samples following intervention and significantly increased in the remainder (25.8%). In samples obtained after exercise intervention, a higher composite miRNA value, made of miR-22-3p and miR-21-5p/miR-451a and spike RNA, was significantly decreased in 65% of the samples and significantly increased in 35% of the samples. In the study of nightly oxygen intervention, when comparing placebo and oxygen, half of the samples showed a significant down-ward change and the other half a significant up-ward change measuring either of the miRNA markers. Samples that had a downward change in the miRNA marker following either intervention originated from patients who had a significantly higher 6-min-walking-distance at baseline (mean difference of 90 m or 80 m following exercise or oxygen intervention, respectively) when compared to samples that had an upward change in the miRNA marker.

Conclusion: These natural animal model and human sample studies further highlight the utility of miRNAs as future biomarkers. The different directional changes of the miRNA markers following supervised exercise training or nightly oxygen intervention could indicate different PAH molecular pathomechanisms (endotypes). Further studies are needed to test this idea.

Pulmonary hypertension and exercise training: a synopsis on the more recent evidences

The benefits of exercise training in virtually all humans, including those with a clinically stable chronic disease are numerous. The potential value lies in the fact that functional capacity is oftentimes significantly compromised. Exercise training not only play a role in reversing some of the pathophysiologic processes associated with chronic diseases but also improves clinical trajectory. Given the significant pathologic consequences associated with pulmonary hypertension and its implications for deteriorating right ventricular function as well as the perceived potential for a precipitous and possibly critical drop in cardiac output during periods of physical exertion, exercise training was historically not recommended for these patients. More recently, a promising body of literature demonstrating the safety and efficacy of exercise training (with benefit on exercise capacity, peak oxygen consumption and quality of life) in pulmonary hypertension patients has emerged, but the conclusion about the effects of exercise training were non-exhaustive and therefore there is still a lack of knowledge regarding exercise training for these patients. Thus, we aim to ascertain the current effectiveness of exercise rehabilitation for pulmonary hypertension by performing a brief overview on the latest currently available evidences in such an "at a glance" synopsis addressed to summarize/quantify the more recent existing body of literature. KEY MESSAGES Exercise training was historically not recommended in pulmonary hypertension. Recently, exercise training safety-efficacy in pulmonary hypertension has emerged. Exercise training should be recommended in addition to optimal medical therapy.

[Update pulmonary arterial hypertension : Definitions, diagnosis, therapy]

The term pulmonary arterial hypertension comprises a group of pulmonary vascular diseases of different etiologies that are characterized by similar precapillary vascular remodeling processes and result in exertional dyspnea and right heart insufficiency. The specific pharmacological treatment approach considers the risk of mortality and phenotypical properties and includes treatment with phosphodiesterase type 5 inhibitors, endothelin receptor antagonists and prostanoids, as well as with more novel substances, such as a soluble guanylyl cyclase stimulator and an oral prostacyclin receptor agonist. The prognosis of the disease is mainly determined by the right heart insufficiency for which there is currently no specific pharmacological treatment. Lung transplantation may be offered as a last option. This review provides an overview of the current European guidelines from 2015 and the recommendations of the Cologne Consensus Conference for pulmonary hypertension from 2016.