Creating a digital approach for promoting physical activity in pediatric pulmonary hypertension: A framework for future interventions

Children with pulmonary hypertension (PH) often demonstrate limited exercise capacity. Data support exercise as an effective nonpharmacologic intervention among adults with PH. However, data on exercise training in children and adolescents are limited, and characteristics of the optimal exercise program in pediatric PH have not been identified. Exercise programs may have multiple targets, including muscle deficits which are associated with exercise limitations in both adult and pediatric PH. Wearable accelerometer sensors measure physical activity volume and intensity in the naturalistic setting and can facilitate near continuous data transfer and bidirectional communication between patients and the study team when paired with informatics tools during exercise interventions. To address the knowledge gaps in exercise training in pediatric PH, we designed a prospective, single arm, nonrandomized pilot study to determine feasibility and preliminary estimates of efficacy of a 16-week home exercise intervention, targeting lower extremity muscle mass and enriched by wearable mobile health technology. The exercIse Training in pulmONary hypertEnsion (iTONE) trial includes (1) semistructured exercise prescriptions tailored to the participant's baseline level of activity and access to resources; (2) interval goal setting fostering self-efficacy; (3) real time monitoring of activity via wearable devices; (4) a digital platform enabling communication and feedback between participant and study team; (5) multiple avenues to assess participant safety. This pilot intervention will provide information on the digital infrastructure needed to conduct home-based exercise interventions in PH and will generate important preliminary data on the effect of exercise interventions in youth with chronic cardiorespiratory conditions to power larger studies in the future.

Pulmonary hypertension alters blood flow distribution and impairs the hyperemic response in the rat diaphragm

Pulmonary hypertension (PH) is characterized by pulmonary vascular remodeling, respiratory muscle and cardiac impairments, and exercise intolerance. Specifically, impaired gas exchange increases work of the diaphragm; however, compromised contractile function precludes the diaphragm from meeting the increased metabolic demand of chronic hyperventilation in PH. Given that muscle contractile function is in part, dependent upon adequate blood flow (Q ˙ ), diaphragmatic dysfunction may be predicated by an inability to match oxygen delivery with oxygen demand. We hypothesized that PH rats would demonstrate a decreased hyperemic response to contractions compared to healthy controls. Methods: Sprague-Dawley rats were randomized into healthy (HC, n = 7) or PH (n = 7) groups. PH rats were administered monocrotaline (MCT) while HC rats received vehicle. Disease progression was monitored via echocardiography. Regional and total diaphragm blood flow and vascular conductance at baseline and during 3 min of electrically-stimulated contractions were determined using fluorescent microspheres. Results: PH rats displayed morphometric and echocardiographic criteria for disease (i.e., acceleration time/ejection time, right ventricular hypertrophy). In all rats, total costal diaphragm Q ˙ increased during contractions and did not differ between groups. In HC rats, there was a greater increase in medial costal Q ˙ compared to PH rats (55% ± 3% vs. 44% ± 4%, p < 0.05), who demonstrated a redistribution of Q ˙ to the ventral costal region. Conclusion: These findings support a redistribution of regional diaphragm perfusion and an impaired medial costal hyperemic response in PH, suggesting that PH alters diaphragm vascular function and oxygen delivery, providing a potential mechanism for PH-induced diaphragm contractile dysfunction.

Safety and effectiveness of standardized exercise training in patients with pulmonary hypertension associated with heart failure with preserved ejection fraction (TRAIN-HFpEF-PH): study protocol for a randomized controlled multicenter trial

BACKGROUND

Left heart failure (HF) is characterized by an elevation in left-sided filling pressures, causing symptoms of dyspnea, impairing exercise capacity, and leading to pulmonary venous congestion and secondary pulmonary hypertension (PH). There is an increased incidence of PH associated with left heart disease, particularly with heart failure with preserved ejection fraction (HFpEF-PH). Treatment possibilities in HFpEF-PH are non-specific and very limited, thus additional pharmacological and non-pharmacological therapeutic strategies are needed. Various types of exercise-based rehabilitation programs have been shown to improve exercise capacity and quality of life (QoL) of HF and PH patients. However, no study focused on exercise training in the population of HFpEF-PH. This study is designed to investigate whether a standardized low-intensity exercise and respiratory training program is safe and may improve exercise capacity, QoL, hemodynamics, diastolic function, and biomarkers in patients with HFpEF-PH.

METHODS

A total of 90 stable patients with HFpEF-PH (World Health Organization functional class II-IV) will be randomized (1:1) to receive a 15-week specialized low-intensity rehabilitation program, including exercise and respiratory therapy and mental gait training, with an in-hospital start, or standard care alone. The primary endpoint of the study is a change in 6-min walk test distance; secondary endpoints are changes in peak exercise oxygen uptake, QoL, echocardiographic parameters, prognostic biomarkers, and safety parameters.

DISCUSSION

To date, no study has investigated the safety and efficacy of exercising specifically in the HFpEF-PH population. We believe that a randomized controlled multicenter trial, which protocol we are sharing in this article, will add important knowledge about the potential utility of a specialized low-intensity exercise and respiratory training program for HFpEF-PH and will be valuable in finding optimal treatment strategies for these patients.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05464238. July 19, 2022.

Pulmoner Arteriyel Hipertansiyonlu Hastalarda İnspiratuar Kas Eğitiminin Fonksiyonel Egzersiz Kapasitesi ve Yaşam Kalitesi Üzerine Etkisi: Bir Sistematik Derleme

Pulmoner Arteriyal Hipertansiyon hastalarında, hastalığın erken dönemlerinde semptomlar eforla ortaya çıkarken, hastalığın ileri evrelerinde dinlenme durumunda da gözlenebilir. Pulmoner Arteriyal Hipertansiyon hastaları için optimize edilmiş tıbbi tedavi bulunmasına rağmen, çoğu Pulmoner Arteriyal Hipertansiyon hastası düşük egzersiz kapasitesi ve yaşam kalitesinden şikayetçidir. Pulmoner Arteriyal Hipertansiyon tedavi parametrelerinden biri pulmoner rehabilitasyondur. Pulmoner rehabilitasyon muldisipliner bir yaklaşımdır. Pulmoner Arteriyal Hipertansiyon için en önemli bileşeni fizyoterapi programıdır. Kişiye özel fizyoterapi programları egzersiz eğitimi, solunum kas eğitimi, hasta eğitimi bileşenlerinden oluşmaktadır. Solunum kas kuvveti eğitimi daha çok spesifik olarak İnspiratuar Kas Eğitimi şeklinde uygulanmaktadır. Pulmoner Arteriyal Hipertansiyonlu hastalar için İnspiratuar Kas Eğitimi uygulamasının genel etkilerini araştıran ve konu alan çalışma sayısı azdır. Bu çalışmanın amacı Pulmoner Arteriyal Hipertansiyonlu hastalarda İnspiratuar Kas Eğitimi’nin hastanın fonksiyonel egzersiz kapasitesinin ve yaşam kalitesinin artmasında etkili midir? sorusunu cevaplamaktır. Ocak 2022 tarihinden önce PubMed, Web of Science, Cochrane Library olmak üzere üç ana veri tabanında arama yapıldı. Arama son 5 yılda yayınlanan randomize kontrollü prospektif çalışmalar olacak şekilde sınırlandırıldı. Pulmoner Arteriyal Hipertansiyonlu hastalarda İnspiratuar Kas Eğitimi uygulanan çalışmalar dahil edildi. Tam metinler okunduktan sonra dahil edilme kriterlerine uygun iki çalışma bulundu. Bu yayınların tümü randomize kontrollü prospektif çalışmalardı. Çalışmalar incelendiğinde, Pulmoner Arteriyal Hipertansiyonlu hastalarda İnspiratuar Kas Eğitimi uygulamasının, fonksiyonel egzersiz kapasitesini ve inspiratuar kas kuvvetini arttırdığı ancak yaşam kalitesini arttırmadaki etkinliğinin belirsiz olduğu sonucuna varıldı.

Exercise-based rehabilitation programmes for pulmonary hypertension

BACKGROUND

Individuals with pulmonary hypertension (PH) have reduced exercise capacity and quality of life. Despite initial concerns that exercise training may worsen symptoms in this group, several studies have reported improvements in functional capacity and well-being following exercise-based rehabilitation.

OBJECTIVES

To evaluate the benefits and harms of exercise-based rehabilitation for people with PH compared with usual care or no exercise-based rehabilitation.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was 28 June 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) in people with PH comparing supervised exercise-based rehabilitation programmes with usual care or no exercise-based rehabilitation.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were 1. exercise capacity, 2. serious adverse events during the intervention period and 3. health-related quality of life (HRQoL). Our secondary outcomes were 4. cardiopulmonary haemodynamics, 5. Functional Class, 6. clinical worsening during follow-up, 7. mortality and 8. changes in B-type natriuretic peptide. We used GRADE to assess certainty of evidence.

MAIN RESULTS

We included eight new studies in the current review, which now includes 14 RCTs. We extracted data from 11 studies. The studies had low- to moderate-certainty evidence with evidence downgraded due to inconsistencies in the data and performance bias. The total number of participants in meta-analyses comparing exercise-based rehabilitation to control groups was 462. The mean age of the participants in the 14 RCTs ranged from 35 to 68 years. Most participants were women and classified as Group I pulmonary arterial hypertension (PAH). Study durations ranged from 3 to 25 weeks. Exercise-based programmes included both inpatient- and outpatient-based rehabilitation that incorporated both upper and lower limb exercise. The mean six-minute walk distance following exercise-based rehabilitation was 48.52 metres higher than control (95% confidence interval (CI) 33.42 to 63.62; I² = 72%; 11 studies, 418 participants; low-certainty evidence), the mean peak oxygen uptake was 2.07 mL/kg/min higher than control (95% CI 1.57 to 2.57; I² = 67%; 7 studies, 314 participants; low-certainty evidence) and the mean peak power was 9.69 W higher than control (95% CI 5.52 to 13.85; I² = 71%; 5 studies, 226 participants; low-certainty evidence). Three studies reported five serious adverse events; however, exercise-based rehabilitation was not associated with an increased risk of serious adverse event (risk difference 0, 95% CI -0.03 to 0.03; I² = 0%; 11 studies, 439 participants; moderate-certainty evidence). The mean change in HRQoL for the 36-item Short Form (SF-36) Physical Component Score was 3.98 points higher (95% CI 1.89 to 6.07; I² = 38%; 5 studies, 187 participants; moderate-certainty evidence) and for the SF-36 Mental Component Score was 3.60 points higher (95% CI 1.21 to 5.98 points; I² = 0%; 5 RCTs, 186 participants; moderate-certainty evidence). There were similar effects in the subgroup analyses for participants with Group 1 PH versus studies of groups with mixed PH. Two studies reported mean reduction in mean pulmonary arterial pressure following exercise-based rehabilitation (mean reduction: 9.29 mmHg, 95% CI -12.96 to -5.61; I² = 0%; 2 studies, 133 participants; low-certainty evidence).

AUTHORS' CONCLUSIONS

In people with PH, supervised exercise-based rehabilitation may result in a large increase in exercise capacity. Changes in exercise capacity remain heterogeneous and cannot be explained by subgroup analysis. It is likely that exercise-based rehabilitation increases HRQoL and is probably not associated with an increased risk of a serious adverse events. Exercise training may result in a large reduction in mean pulmonary arterial pressure. Overall, we assessed the certainty of the evidence to be low for exercise capacity and mean pulmonary arterial pressure, and moderate for HRQoL and adverse events. Future RCTs are needed to inform the application of exercise-based rehabilitation across the spectrum of people with PH, including those with chronic thromboembolic PH, PH with left-sided heart disease and those with more severe disease.

Exercise Training in Pulmonary Hypertension: AN UPDATED SYSTEMATIC REVIEW WITH META-ANALYSIS

PURPOSE

Given that previous reviews on exercise training in pulmonary hypertension (PH) were largely based on a small number of randomized controlled trials (RCT), their conclusions are subject to bias. This review sought to identify the impact of exercise training on functional capacity and health-related quality of life (HRQoL) in PH using advanced statistical approaches such as meta-analysis by stratification according to study design.

REVIEW METHODS

Five databases were searched from January 2015 to April 2020 to update a previous review. Included articles had data extracted, risk of bias (ROB) assessed, and quality rating performed. Data were analyzed using meta-analysis with a random-effects model for 6-min walk test (6MWT) distance and HRQoL. Heterogeneity was explored using stratified meta-analysis, within patient correlation and meta-regression.

RESULTS

A total of 28 studies (11 RCT, 12 pre-/post-studies, 2 two-group non-RCT, and three case series) consisting of 1264 patients were included. Meta-analysis of six RCT demonstrated an improved 6MWT distance by 49.5 m (95% CI, 27.2-71.8: I2 = 73%; 254 participants; low-moderate ROB) with a low correlation coefficient of 0.34, while the 12 pre-/post-non-RCT showed an improvement of 68.36 m (95% CI, -86.78 to -49.94: I2 = 37%; 746 participants; high ROB) along with improvements in V˙ o2peak (weighted mean difference [WMD] = 3.03 mL/kg/min, 95% CI, 2.17-3.90: I2 = 0%, P = .82), and HRQoL (WMD = 2.74: 95% CI, -0.82 to 6.30). Metaregression showed that the benefit of exercise on 6MWT distance did not significantly vary across the trial study characteristics.

CONCLUSION

This updated review identified an additional body of evidence supporting the efficacy of exercise training on 6MWT distance and HRQoL in stable PH patients. These benefits appeared to be consistent across models of delivery.

Pulmonary rehabilitation of chronic pulmonary diseases (the review of clinical trials, national and international recommendations)

The review of data from randomized clinical trials, results of systematic reviews, international and national clinical recommendations on the problem of pulmonary rehabilitation in chronic pulmonary disease was carried out. This analysis of the studies included the databases eLibrary, Medline, PubMed and Cochrane libraries on the problem of pathophysiology and methods of physical rehabilitation of chronic pulmonary disease. The analysis took into account the opinions of expert groups of clinical recommendations developers of the Russian respiratory society, the European respiratory society, and the American thoracic society, presented in this review. The data of studies confirm the clinical effectiveness of physical rehabilitation methods for chronic pulmonary disease that take into account the unique needs of a complex patient. Pulmonary rehabilitation improves the physical activity, quality of life associated with health, reduces the incidence of exacerbations and mortality of patients with chronic pulmonary disease. Increasing the availability and improving pulmonary rehabilitation programs based on individual assessment of the patient's physical capabilities will increase the use of this method of treatment.

Exercise Rehabilitation Training in Patients with Pulmonary Hypertension: A Review

Pulmonary hypertension (PH) has a high morbidity and mortality. Despite the existing disease-targeted therapy, most patients with PH continue to suffer from difficulty in breathing, exercise intolerance, and reduced quality of life. Recently, a large body of research results has suggested that exercise rehabilitation training (ERT) seems to be a beneficial, safe, and cost-effective treatment for patients with PH. However, knowledge gaps still exist for a uniformly accepted ERT protocol, the modality, duration, intensity, and frequency of ERT in PH. The purpose of this review is to summarise the existing research evidence and knowledge, aiming to strengthen clinicians' awareness of the application of ERT in patients with PH. PubMed databases were systematically searched for eligible studies. Twelve (12) randomised controlled trials and other important studies documenting effectiveness, safety, and adverse events of ERT are summarised. Additionally, the modality, duration, intensity, and frequency of various types of ERT and future research directions are discussed. In summary, ERT is generally effective and safe for PH patients as an adjuvant treatment to disease-specific therapy. It can improve the exercise capacity and tolerance, skeletal and respiratory muscle performance, cardiopulmonary function, and quality of life of PH patients. In view of the occurrence of a small number of adverse events, we currently recommend a combination of in-hospital and home-based ERT under close supervision. In the future, more multi-centre randomised controlled studies are needed to evaluate the effectiveness and feasibility of long-term, community, or home-based ERT, as well as to explore the molecular mechanism behind it.

A wrinkle in time: circadian biology in pulmonary vascular health and disease

An often overlooked element of pulmonary vascular disease is time. Cellular responses to time, which are regulated directly by the core circadian clock, have only recently been elucidated. Despite an extensive collection of data regarding the role of rhythmic contribution to disease pathogenesis (such as systemic hypertension, coronary artery, and renal disease), the roles of key circadian transcription factors in pulmonary hypertension remain understudied. This is despite a large degree of overlap in the pulmonary hypertension and circadian rhythm fields, not only including shared signaling pathways, but also cell-specific effects of the core clock that are known to result in both protective and adverse lung vessel changes. Therefore, the goal of this review is to summarize the current dialogue regarding common pathways in circadian biology, with a specific emphasis on its implications in the progression of pulmonary hypertension. In this work, we emphasize specific proteins involved in the regulation of the core molecular clock while noting the circadian cell-specific changes relevant to vascular remodeling. Finally, we apply this knowledge to the optimization of medical therapy, with a focus on sleep hygiene and the role of chronopharmacology in patients with this disease. In dissecting the unique relationship between time and cellular biology, we aim to provide valuable insight into the practical implications of considering time as a therapeutic variable. Armed with this information, physicians will be positioned to more efficiently use the full four dimensions of patient care, resulting in improved morbidity and mortality of pulmonary hypertension patients.

Effects of respiratory training on ventilation potential and extubation time in patients with tracheotomy: A protocol for systematic review and meta-analysis

BACKGROUND

In the early treatment of critical patients, tracheotomy is often performed to improve ventilation. Clinical practices usually start respiratory training after the artificial airway is removed. It is still controversial whether respiratory training during tube occlusion has effects on patients' ventilation potential and tube occlusion time. Therefore, this study used Meta-analysis to evaluate the effects of respiratory training on patients' ventilation potential and tube occlusion time during tracheotomy in patients with tube occlusion, so as to provide evidence for rehabilitation treatment.

METHODS

Wanfang, Chinese Biomedical Literature Database, Chinese National Knowledge Infrastructure, the Chongqing VIP Chinese Science and Technology Periodical Database, PubMed, Embase, and Web of Science were searched through the computer and the randomized controlled trials of respiratory training on ventilation potential and extubation time in patients experiencing tracheotomy were collected as well. The searching time is limited to October 2021. The language restrictions are Chinese and English. Meta-analysis is performed by using RevMan5.4.

RESULTS

The results of this meta-analysis will be submitted to a peer-reviewed journal for publication.

CONCLUSION

This study will provide the latest evidence for the rehabilitation training of patients who underwent tracheotomy.

OSF REGISTRATION NUMBER

DOI 10.17605/OSF.IO/6UCQF.

The effects of pulmonary hypertension on skeletal muscle oxygen pressures in contracting rat spinotrapezius muscle

NEW FINDINGS

What is the central question of this study? Does impairment in the dynamics of O₂ transport in skeletal muscle during a series of contractions constitute a potential mechanism underlying reduced exercise capacity in pulmonary hypertension? What is the main finding and its importance? Pulmonary hypertension compromises the dynamic matching of skeletal muscle O₂ delivery-to-utilization following contraction onset in the rat spinotrapezius muscle. These results implicate a role for vascular dysfunction in the slow V ̇ O 2 kinetics and exercise intolerance present in pulmonary hypertension.

ABSTRACT

Pulmonary hypertension (PH) is characterized by pulmonary vascular dysfunction and exercise intolerance due, in part, to compromised pulmonary and cardiac function. We tested the hypothesis that there are peripheral (i.e., skeletal muscle) aberrations in O₂ delivery ( Q ̇ O 2 )-to-O₂ utilization ( V ̇ O 2 ) matching and vascular control that might help to explain poor exercise tolerance in PH. Furthermore, we investigated the peripheral effects of nitric oxide (NO) in attenuating these decrements. Male Sprague-Dawley rats (n = 21) were administered monocrotaline (MCT; 50 mg/kg, i.p.) to induce PH. Disease progression was monitored via echocardiography. Phosphorescence quenching determined the O₂ partial pressure in the interstitial space ( P O 2 is ) in the spinotrapezius muscle at rest and during contractions under control (SNP-) and NO-donor (sodium nitroprusside, SNP+) conditions. MCT rats displayed right ventricular (RV) hypertrophy (right ventricle/(left ventricle + septum): 0.44 (0.13) vs. 0.28 (0.05)), pulmonary congestion, increased RV systolic pressure (48 (18) vs. 20 (8) mmHg) and arterial hypoxaemia ( P a O 2 : 64 (9) vs. 82 (9) mmHg) compared to healthy controls (HC) (P < 0.05). P O 2 is was significantly lower in MCT rats during the first 30 s of SNP- contractions. SNP superfusion elevated P O 2 is in both groups; however, MCT rats demonstrated a lower P O 2 is throughout SNP+ contractions versus HC (P < 0.05). Thus, for small muscle mass exercise in MCT rats, muscle oxygenation is impaired across the rest-to-contractions transition and exogenous NO does not raise the Q ̇ O 2 -to- V ̇ O 2 ratio in contracting muscle to the same levels as HC. These data support muscle Q ̇ O 2 -to- V ̇ O 2 mismatch as a potential contributor to slow V ̇ O 2 kinetics and therefore exercise intolerance in PH and suggest peripheral vascular dysfunction or remodelling as a possible mechanism.

Outcome Measures Used in Studies of Rehabilitation in Pulmonary Hypertension

Rationale: The evidence base for rehabilitation in pulmonary hypertension is expanding, but adoption in clinical practice is limited.Objectives: The World Health Organization International Classification for Functioning, Disability and Health identifies three health domains: Body Functions/Structures, Activity and Participation in society. To ensure that the wider impact of rehabilitation in pulmonary hypertension is accurately assessed, it is important that study endpoints reflect all three domains.Methods: A systematic review of the literature was conducted to identify studies of rehabilitation in patients with pulmonary hypertension from 2006 to 2019.Results: Searches across five databases yielded 2,564 articles, of which 34 met eligibility criteria; 50 different outcome measures (mean = 5, minimum = 1, maximum = 9) were identified. When mapped onto the World Health Organization International Classification for Functioning, Disability and Health, 48% of instances of outcome usage were measures of Body Functions/Structure, 33% were measures of Activity, and 18% were measures of Participation. Measures of Participation were not included in seven studies (21%).Conclusions: Studies of rehabilitation in pulmonary hypertension have focused primarily on measures of Body Functions/Structure; the impact in other health domains is not well characterized. Greater inclusion of outcome measures reflecting Activity and Participation in society is needed to allow assessment of the wider impact of rehabilitation in patients with pulmonary hypertension.

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.

The Experience, Prerequisites, and the Barriers in Organizing a Specialized Rehabilitation Program for Patients with Pulmonary Hypertension

BACKGROUND

Pulmonary hypertension (PH) is a severe progressive disease, associated with reduced exercise capacity and poor quality of life. Although scientific evidence supports the incorporation of specialized training in the treatment of PH, it is only available in a few countries.

OBJECTIVES AND METHODS

This article aims to share the experience of implementing a PH rehabilitation program, to summarize the barriers and prerequisites for launching this service, and to assess its early effect. We retrospectively analyzed our pathway in organizing this program, by singling out essential steps.

RESULTS

The preparation phase took about 14 months. Establishing and running of a PH rehabilitation program required dedicated rehabilitation specialists to join the multidisciplinary PH expert team. Team members needed to gain special knowledge on exercise training in severely compromised patients; thus, supervision and education by experienced consultants was crucial. The main eligibility criteria for patients were stable status, optimal medical treatment, and motivation to undergo the training. The first results evaluating the effect of a specialized PH training program in 9 patients are promising. Seven of them improved their functional capacity over the period of 15 weeks.

CONCLUSIONS

Despite a number of challenges and barriers, the implementation of a specialized rehabilitation program should be encouraged in a few dedicated PH expert centers per country, who are capable to fulfill all prerequisites and organizational aspects. Local PH experts, supervision by an experienced center, in-patient rehabilitation facilities, dedicated personnel, equipment, and patient motivation are essential.

The benefit of exercise-based rehabilitation programs in patients with pulmonary hypertension: a systematic review and meta-analysis of randomized controlled trials

Several studies have suggested that exercise capacity and quality of life are reduced in patients with pulmonary hypertension, and exercise-based rehabilitation can improve exercise capacity and quality of life in patients with pulmonary hypertension. The aim of this study is to assess the efficacy and safety of exercise-based rehabilitation in patients with pulmonary hypertension through a meta-analysis of randomized controlled trials. We searched PubMed, Embase, Medline, and the Cochrane Central Register of Controlled Trials up to November 2018. All randomized controlled trials comparing exercise capacity and quality of life between patients undergoing exercise-based rehabilitation and those undergoing non-exercise training were included. Data were extracted separately and independently by two investigators, and discrepancies were arbitrated by the third investigator. We used the random-effects model to analyze the results, the GRADE to assess the risk of bias in the included studies, and I² statistic to estimate the degree of heterogeneity. Nine randomized controlled trials are included; however, only seven randomized controlled trials were able to extract data. Including inpatients and outpatients, the total number of participants was 234, most of whom were diagnosed as pulmonary artery hypertension. The study duration ranged from 3 to 15 weeks. The mean six-minute walking distance after exercise training was 51.94 m higher than control (27.65-76.23 m, n = 234, 7 randomized controlled trials, low quality evidence), the mean peak oxygen uptake was 2.96 ml/kg/min higher (2.49-3.43 ml/kg/min, n = 179, 4 randomized controlled trials, low-quality evidence) than in the control group. In conclusion, our finding suggests that an exercise-based training program positively influences exercise capacity in patients with pulmonary hypertension.

A Mobile Health Intervention to Increase Physical Activity in Pulmonary Arterial Hypertension

BACKGROUND

Supervised exercise training improves outcomes in patients with pulmonary arterial hypertension (PAH). The effect of an unsupervised activity intervention has not been tested.

RESEARCH QUESTION

Can a text-based mobile health intervention increase step counts in patients with PAH?

STUDY DESIGN AND METHODS

We performed a randomized, parallel arm, single-blind clinical trial. We randomized patients to usual care or a text message-based intervention for 12 weeks. The intervention arm received three automated text messages per day with real-time step count updates and encouraging messages rooted in behavioral change theory. Individual step targets increased by 20% every 4 weeks. The primary end point was mean week 12 step counts. Secondary end points included the 6-min walk test, quality of life, right ventricular function, and body composition.

RESULTS

Among 42 randomized participants, the change in raw steps between baseline and week 12 was higher in the intervention group (1,409 steps [interquartile range, -32 to 2,220] vs -149 steps [interquartile range, -1,010 to 735]; P = .02), which persisted after adjustment for age, sex, baseline step counts, and functional class (model estimated difference, 1,250 steps; P = .03). The intervention arm took a higher average number of steps on all days between days 9 and 84 (P < .05, all days). There was no difference in week 12 six-minute walk distance. Analysis of secondary end points suggested improvements in the emPHasis-10 score (adjusted change, -4.2; P = .046), a reduction in visceral fat volume (adjusted change, -170 mL; P = .023), and nearly significant improvement in tricuspid annular plane systolic excursion (model estimated difference, 1.2 mm; P = .051).

INTERPRETATION

This study demonstrated the feasibility of an automated text message-based intervention to increase physical activity in patients with PAH. Additional studies are warranted to examine the effect of the intervention on clinical outcomes.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov; No. NCT03069716; URL: www.clinicaltrials.gov.

[Group Training of Patients with Chronic Lung Diseases under Outpatient Conditions - Recommendations of the Working Group Lung Sports in Germany and the German Airways League]

To improve acceptance and use of physical training by patients with chronic lung diseases, recommendations for performing lung exercises on an outpatient basis in a group setting are given by experts in physical training, sports therapists and pulmonologists. The evidence-based positive effects of physical training were analyzed for asthma , COPD, interstitial lung diseases, cystic fibrosis, lung carcinoma, and pulmonary hypertension. The requirements for lung exercises in outpatient groups as well as compensation by care providers were given on the basis of legal regulations. Furthermore, the main items of the training units as well as supervision by specially trained group leaders in relation to the severity of the underlying lung disease are described. Finally, aspects of safety of the participating patients are discussed, including the prevention of infection with corona-2-virus.

Exercise Training for Pulmonary Hypertension: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Pulmonary hypertension (PH) is a chronic disease with a notable health burden; regular exercise may improve specific health outcome measures.

OBJECTIVE

The objective of this meta-analysis was to estimate the effectiveness of exercise training for PH patients.

DATA SOURCES

PubMed, CINAHL, SportDiscuss and Google Scholar databases and reference lists of included studies were searched.

STUDY SELECTION

The selection criteria were randomized controlled trials (RCTs) employing an exercise training intervention. Data were extracted from the entered studies for analysis. The primary outcomes were peak oxygen uptake (VO_2peak), anaerobic threshold (AT), 6-minute walk distance (6-MWD), and quality of life (QoL) measures (physical component score and mental component score). The analysis included 9 articles with a total of 302 participants: intervention (n = 154), and control (n = 148).

RESULTS

In the pooled analysis, improvements were seen in: VO_2peak, mean difference (MD) 2.79 ml/kg/min (95% CI 2.00 to 3.59, p < 0.00001); AT, MD 107.83 ml/min (95% CI 39.64 to 176.00, p = 0.002); and 6-MWD, MD 46.67 meters (95% CI 32.39 to 60.96, p < 0.00001). Differences were found in the SF-36 physical component score MD 3.57 (95% CI 2.04 to 5.10, p < 0.00001) and the SF-36 mental component score MD 3.92 (95% CI 1.92 to 5.91, p = 0.001).

CONCLUSION

This meta-analysis demonstrates exercise training has a beneficial effect on fitness, walking performance, and self-reported QoL in PH patients.

Safety of exercise therapy after acute pulmonary embolism

OBJECTIVE

The role of exercise therapy after acute pulmonary embolism (PE) is unknown. Exercise therapy is safely used after myocardial infarction and chronic obstructive pulmonary disease. The aim of this study was to investigate the safety of exercise therapy after acute PE.

METHODS

We implemented a 3-month exercise program after acute PE. Outcomes were death, bleeding, readmissions, recurrent events, changes in peak VO2 and quality of life (QoL).

RESULTS

A total of 23 patients were enrolled and received anticoagulation; no adverse events were reported during the exercise period. One death, 1 DVT and 5 readmissions were reported due to non-exercise related reasons. Functional capacity improved as evidenced by an increased peak VO2 at 3 months (+3.9 ± 5.6 mL/kg/min; p = 0.05). Improvement in QoL was observed at 6-months on the functional (+17.0 ± 22.6, p = 0.03) and physical health factor scales (+0.9 ± 4.6, p = 0.03).

CONCLUSION

Exercise therapy is feasible and safe in appropriately anticoagulated patients after PE.

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.

Effects of upper extremity aerobic exercise training on oxygen consumption, exercise capacity, dyspnea and quality of life in patients with pulmonary arterial hypertension

BACKGROUND

Pulmonary and extrapulmonary impairments are prevalent in pulmonary arterial hypertension (PAH) which is a rare, chronic and progressive disease.

OBJECTIVES

To investigate the effects of upper extremity aerobic exercise training on exercise capacity, oxygen consumption, dyspnea and quality of life in patients with PAH.

METHODS

In a prospective, randomized controlled, double-blinded study, eleven patients in training group applied upper extremity aerobic exercise training (50-80% of maximal heart rate), 15-45 min/day, 3 days a week for 6 weeks and 11 patients in control group alternating active upper extremity exercises for the same period. Exercise capacity evaluated using six minute walk test (6MWT), oxygen consumption simultaneously measured during 6MWT using a portable instrument, dyspnea modified Borg scale and Modified Medical Research Council dyspnea scale and quality of life Short Form 36 Health Survey, before and after the exercise training.

RESULTS

Baseline characteristics of groups were similar (p>0.05). Dyspnea (p<0.001) and peak oxygen consumption (p = 0.031) were significantly improved in training group compared the controls. Dyspnea, exercise capacity, peak oxygen consumption, minute ventilation, tidal volume, end tidal carbon-dioxide pressure, and vitality, social functioning and role-physical were significantly improved within training group (p<0.05). Oxygen consumption at anaerobic threshold were significantly decreased within control group (p<0.05).

CONCLUSIONS

Upper extremity aerobic exercise training improves oxygen consumption, and decreases dyspnea perception. It is a safe and effective intervention in patients with PAH. (ClinicalTrials.gov registration: NCT02371733).

Attitudes towards exercise among medical specialists who manage patients with pulmonary hypertension

Exercise training was not traditionally recommended for patients with pulmonary hypertension. However, recent work has demonstrated that exercise improves endurance and quality-of-life in patients with pulmonary hypertension. Unfortunately, patients with pulmonary hypertension are often sedentary. While some studies have examined patient attitudes to exercise, none have investigated physician perspectives on exercise in patients with pulmonary hypertension. This multinational survey of physicians involved in treating patients with pulmonary hypertension sought to ascertain physician attitudes to exercise and physician-identified barriers and enablers of exercise in this patient population. We collected cross-sectional survey data from a cohort of 280 physicians, including rehabilitation physicians, cardiologists, respiratory physicians and rheumatologists. We found that overall, 86% physicians recommended exercise, in line with current guidelines, although there were differences in the rationale for prescribing exercise and in the type of exercise prescription. Barriers to exercise included patient-related factors, such as patient ill health preventing exercise; poor patient motivation and lack of understanding regarding the benefits of exercise. Systemic barriers included cost/funding issues and limited availability of appropriate services. Perceived enablers of exercise included access to appropriate programmes, provision of education and supportive treating clinicians. Further research is required to identify and implement interventions to promote physical activity in patients with pulmonary hypertension.

Effectiveness and safety of exercise training and rehabilitation in pulmonary hypertension: a systematic review and meta-analysis

Background

Pulmonary hypertension (PH) is a chronic progressive disease characterized by increasing pulmonary vascular resistance, poor prognosis and high disability rate. Although many targeted drugs for PH have been put to clinical use, most patients still have poor exercise tolerance and quality of life. Exercise training is considered to further improve exercise capacity and quality of life in patients with PH, but it has not been fully studied and utilized. The aim of this systematic review and meta-analysis is to evaluate the effectiveness and safety of exercise training in patients with PH.

Methods

A search was conducted for the meta-analysis using the databases PubMed, Embase, Cochrane Library, including literature published before December 2018. The primary outcome of this meta-analysis was a change in the 6-minute walk distance (6MWD). In addition, peak oxygen uptake (PeakVO₂), resting pulmonary arterial systolic pressure (PASP_rest), resting heart rate (HR_rest), peak exercise heart rate (HR_peak), oxygen uptake anaerobic threshold (VO₂ at AT), maximum workload and quality of life (QoL) were also assessed.

Results

A total of 651 patients in 17 studies were included. A meta-analysis showed that exercise training was associated with significant improvement in the 6MWD [weighted mean difference (WMD): 64.75 m (95% CI: 53.19–76.31 m, P<0.001)], peakVO₂ [WMD: 1.78 mL/min/kg (95% CI: 1.27–2.29 mL/min/kg, P<0.001)], HR_peak [WMD: 11.07 beats/min (95% CI: 8.04–14.11 beats/min, P<0.001)] and QoL measured by SF-36 questionnaire subscale scores. Furthermore, exercise training is well tolerated, and no major adverse event occurred related to exercise training.

Conclusions

Exercise training is associated with a significant improvement in exercise capacity, cardiorespiratory fitness and quality of life among patients with PH and proved to be safe for stable PH patients with optimization of medical therapy. However, more large-scale multicenter studies are needed to confirm the effectiveness and safety of exercise training in patients with PH.

Mitochondria in the Pulmonary Vasculature in Health and Disease: Oxygen-Sensing, Metabolism, and Dynamics

In lung vascular cells, mitochondria serve a canonical metabolic role, governing energy homeostasis. In addition, mitochondria exist in dynamic networks, which serve noncanonical functions, including regulation of redox signaling, cell cycle, apoptosis, and mitochondrial quality control. Mitochondria in pulmonary artery smooth muscle cells (PASMC) are oxygen sensors and initiate hypoxic pulmonary vasoconstriction. Acquired dysfunction of mitochondrial metabolism and dynamics contribute to a cancer-like phenotype in pulmonary arterial hypertension (PAH). Acquired mitochondrial abnormalities, such as increased pyruvate dehydrogenase kinase (PDK) and pyruvate kinase muscle isoform 2 (PKM2) expression, which increase uncoupled glycolysis (the Warburg phenomenon), are implicated in PAH. Warburg metabolism sustains energy homeostasis by the inhibition of oxidative metabolism that reduces mitochondrial apoptosis, allowing unchecked cell accumulation. Warburg metabolism is initiated by the induction of a pseudohypoxic state, in which DNA methyltransferase (DNMT)-mediated changes in redox signaling cause normoxic activation of HIF-1α and increase PDK expression. Furthermore, mitochondrial division is coordinated with nuclear division through a process called mitotic fission. Increased mitotic fission in PAH, driven by increased fission and reduced fusion favors rapid cell cycle progression and apoptosis resistance. Downregulation of the mitochondrial calcium uniporter complex (MCUC) occurs in PAH and is one potential unifying mechanism linking Warburg metabolism and mitochondrial fission. Mitochondrial metabolic and dynamic disorders combine to promote the hyperproliferative, apoptosis-resistant, phenotype in PAH PASMC, endothelial cells, and fibroblasts. Understanding the molecular mechanism regulating mitochondrial metabolism and dynamics has permitted identification of new biomarkers, nuclear and CT imaging modalities, and new therapeutic targets for PAH. © 2020 American Physiological Society. Compr Physiol 10:713-765, 2020.

A randomized controlled trial on inspiratory muscle training in pulmonary hypertension: Effects on respiratory functions, functional exercise capacity, physical activity, and quality of life

BACKGROUND

Impaired respiratory muscle function may be one of the causes of increased dyspnea, reduced exercise capacity, and physical activity (PA), and poor quality of life in pulmonary hypertension (PH).

OBJECTIVE

To investigate the effects of threshold inspiratory muscle training (TIMT) on respiratory functions, functional exercise capacity, PA, and QoL in patients with PH.

METHODS

Thirty patients with PH were randomly allocated to a TIMT (n = 15) and sham group (n = 15). Three patients in the sham group could not participate in the program. The TIMT group (n = 15) trained at 30% of the maximal inspiratory pressure (MIP), and the sham group (n = 12) performed at lowest pressure without change in threshold pressure. In both groups, patients performed TIMT at home for 15 min, twice per day, with the MIP load determined by the trainer, and were supervised once weekly at the hospital for eight weeks. The primary outcomes were MIP and maximal expiratory pressure (MEP). The secondary outcome measures included spirometric measurements, six-minute walking distance (6MWD), PA (SenseWear armband and International Physical Activity Questionnaire-Short Form-IPAQ-Short Form), and QoL (Minnesota Living with Heart Failure-MLHF).

RESULTS

After the training, changes in MIP (p = 0.023) were higher in the intervention group compared with the sham group. Differences in MEP, FEV1 (%), FVC (%), FEV1/FVC (%), 6MWD, %6MWD, IPAQ-SF, MLHFQ, and armband parameters were not significantly different between the groups (p > 0.05).

CONCLUSIONS

The results of the study demonstrated that TIMT could increase MIP and did not improve other parameters of respiratory functions, functional exercise capacity, PA, and QoL in patients with PH.

The role of cardiopulmonary exercise testing and training in patients with pulmonary hypertension: making the case for this assessment and intervention to be considered a standard of care

Introduction: Pulmonary hypertension (PH) is a broad pathophysiological disorder primarily characterized by increased pulmonary vascular resistance due to multiple possible etiologies. Patients typically present with multiple complaints that worsen as disease severity increases. Although initially discouraged due to safety concerns, exercise interventions for patients with PH have gained wide interest and multiple investigations have established the effective role of exercise training in improving the clinical profile, exercise tolerance, and overall quality of life.Areas covered: In this review, we discuss the pathophysiology of PH during rest and exercise, the role of cardiopulmonary exercise testing (CPX) in the diagnosis and prognosis of PAH, the role of exercise interventions in this patient population, and the expected physiological adaptations to exercise training.Expert opinion: Exercise testing, in particular CPX, provides a wealth of clinically valuable information in the PH population. Moreover, the available evidence strongly supports the safety and efficacy of exercise training as a clinical tool in improving exercise tolerance and quality of life. Although clinical trials investigating the role of exercise in this PH population are relatively few compared to other chronic conditions, current available evidence supports the clinical implementation of exercise training as a safe and effective treatment modality.

Skeletal and Respiratory Muscle Dysfunctions in Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a rare disease, which leads to the progressive loss and remodeling of the pulmonary vessels, right heart failure, and death. Different clinical presentations can be responsible for such a bad prognosis disease and the underlying mechanisms still need to be further examined. Importantly, skeletal and respiratory muscle abnormalities largely contribute to the decreased quality of life and exercise intolerance observed in patients with PAH. At the systemic level, impaired oxygen supply through reduced cardiac output and respiratory muscle dysfunctions, which potentially result in hypoxemia, is associated with altered muscles vascularization, inflammation, enhanced catabolic pathways, and impaired oxygen use through mitochondrial dysfunctions that are likely participate in PAH-related myopathy. Sharing new insights into the pathological mechanisms of PAH might help stimulate specific research areas, improving the treatment and quality of life of PAH patients. Indeed, many of these muscular impairments are reversible, strongly supporting the development of effective preventive and/or therapeutic approaches, including mitochondrial protection and exercise training.

[Physical rehabilitation of patients with pulmonary hypertension]

Pulmonary arterial hypertension (PAH) is characterized by characterized by a continuous increase in precapillary pulmonary vascular resistance with a progressive decrease in cardiac output, which leads to progressive dyspnea, fatigue, and deterioration of exercise capacity. Traditionally, the patients have been advised to limit physical exercises. Recent studies suggest that there are improvements in exercise capacity, quality of life, muscle function, and pulmonary circulation when cardiovascular and pulmonary rehabilitation programs are implemented. According to the 2015 European Society of Cardiology guidelines for the management of patients with PAH, physical rehabilitation is indicated for clinically stable patients who receive drug therapy for this disease. There are various physical rehabilitation programs, but there is no generally accepted protocol for physical exercises in patients with PAH. The review highlights the pathophysiological mechanisms for reducing exercise capacity in patients with PAH; methods for assessing the right ventricular contractile reserve, the effect of physical stress on the cardiovascular system, lungs, and muscles; the existing physical rehabilitation programs, complications and ways to overcome them are considered. Clinical trials studies are also briefly analyzed; promising areas for further development and improvement of rehabilitation programs are considered.

Exploring a physiotherapy well-being review to deliver community-based rehabilitation in patients with pulmonary hypertension

BACKGROUND

Highly structured, supervised exercise training has been shown to be beneficial in patients with pulmonary hypertension. Despite evidence of the effectiveness of community-based rehabilitation in other cardiopulmonary diseases, there are limited data in patients with pulmonary hypertension.

METHODS

This prospective study evaluated the intervention of a physiotherapist well-being review in patients with pulmonary hypertension who had been established on targeted drug therapy for between 3 and 12 months. The intervention included a detailed consultation assessing functional, social and motivational status to identify individual patient rehabilitation goals and facilitate tailored referrals to community-based services.

RESULTS

One hundred and thirty-eight patients (79% pulmonary arterial hypertension, 17% chronic thromboembolic disease), age 67 ± 14 years, diagnosed over a one year period were evaluated between July 2017 and January 2018. Fifty-two per cent of patients were referred to community-based pulmonary rehabilitation programmes, 19% received other forms of community rehabilitation, 17% were given exercise advice, 5% had an assessment of social support and 7% declined any intervention. At the end of the study, 32% of patients were undertaking independent exercise.

CONCLUSION

This study has identified that the majority of patients with pulmonary hypertension who are optimised on targeted drug therapy have rehabilitation needs. The use of a physiotherapy well-being review can identify this need and facilitate access to community-based rehabilitation. Further research is required to evaluate the efficacy of such interventions in pulmonary hypertension.

The role of rehabilitation in patients with pulmonary arterial hypertension

PURPOSE OF REVIEW

The current review summarizes the latest evidence of the effects of exercise training for pulmonary hypertension patients demonstrated by six randomized controlled trails and 20 further studies. As the availability of exercise training is still limited it is important to raise awareness of the body of evidence showing the benefit for the patients and the limitations.

RECENT FINDINGS

The effects of exercise training on exercise capacity, hemodynamics as well as quality of life are described as well as different settings and components of exercise training. Associated adverse events are critically reviewed and strategies for avoidance of these events discussed. Lastly, the most important issues of availability and reimbursement of a specialized exercise training program are examined and the future path is outlined to improve patient access.

SUMMARY

The latest publications on this topic strengthen the call for international multicenter randomized controlled trials to establish the feasibility of exercise training in different healthcare systems and to enhance patient access to these programs.

ERS statement on exercise training and rehabilitation in patients with severe chronic pulmonary hypertension

Objectives of this European Respiratory Society task force were to summarise current studies, to develop strategies for future research and to increase availability and awareness of exercise training for pulmonary hypertension (PH) patients.

An evidence-based approach with clinical expertise of the task force members, based on both literature search and face-to-face meetings was conducted. The statement summarises current knowledge and open questions regarding clinical effects of exercise training in PH, training modalities, implementation strategies and pathophysiological mechanisms.

In studies (784 PH patients in total, including six randomised controlled trials, three controlled trials, 10 prospective cohort studies and four meta-analyses), exercise training has been shown to improve exercise capacity, muscular function, quality of life and possibly right ventricular function and pulmonary haemodynamics. Nevertheless, further studies are needed to confirm these data, to investigate the impact on risk profiles and to identify the most advantageous training methodology and underlying pathophysiological mechanisms.

As exercise training appears to be effective, cost-efficient and safe, but is scarcely reimbursed, support from healthcare institutions, commissioners of healthcare and research funding institutions is greatly needed. There is a strong need to establish specialised rehabilitation programmes for PH patients to enhance patient access to this treatment intervention.

Exercise Training and Rehabilitation in Pulmonary Hypertension

Within the last years, exercise training and rehabilitation as add-on to medical treatment has become an emerging field in pulmonary hypertension. Owing to the beneficial effects of exercise training in pulmonary hypertension, the new European Respiratory Society/European Society of Cardiology guidelines for pulmonary hypertension recommended a supervised and closely monitored exercise and respiratory training/rehabilitation as add-on to medical therapy (class IIa, level of evidence B). In this article, different training modalities, effects of exercise training, possible pathobiological mechanisms of action, and future research questions are discussed.

Exercise rehabilitation programmes for pulmonary hypertension: a systematic review of intervention components and reporting quality

Objectives

To identify the components, and assess the reporting quality, of exercise training interventions for people living with pulmonary hypertension.

Design

Systematic review with analysis of intervention reporting quality using the Consensus on Exercise Reporting Template (CERT).

Data sources

Eligible studies in the Cochrane Systematic Review of exercise-based rehabilitation for pulmonary hypertension, updated with a new search of relevant databases from 1 August 2016 to 15 January 2018.

Eligibility criteria

Peer-reviewed journal articles of randomised and non-randomised controlled trials, and non-controlled prospective observational studies, investigating dynamic exercise training interventions in adult humans with diagnosed pulmonary hypertension, reporting on at least one physiological and/or psychosocial outcome.

Results

Interventions typically involved cycle ergometry and walking. They were delivered as 3-week inpatient, or outpatient and/or home-based programmes, lasting for 4–15 weeks. Components relating specifically to exercise prescription were described satisfactorily and in more detail than motivational/behavioural change strategies, adherence and fidelity. Mean CERT score was 13.1 (range 8–17) out of a possible maximum score of 19. No studies fully reported every aspect of an exercise intervention to the standard recommended by CERT.

Summary/conclusion

Considerable variability was evident in the components and reporting quality of interventions for exercise rehabilitation studies in pulmonary hypertension. Interventional studies using exercise training should pay greater attention to describing motivational/behavioural change strategies, adherence and fidelity. Detailed description of these parameters is essential for the safe and effective replication of exercise rehabilitation interventions for pulmonary hypertension in clinical practice.

Trial registration number

CRD42018085558.

Safe and effective exercise training for patients with pulmonary arterial hypertension: putting current evidence into clinical practice

INTRODUCTION

While there have been significant advances in the medical treatment of pulmonary arterial hypertension (PAH), life expectancy, and quality of life remain reduced in this disease. Strenuous exercise may be hazardous for PAH patients; however, several relatively small trials have confirmed that exercise training programs can be used safely and effectively as adjunctive treatment for selected patients. The use of exercise training is now recommended in consensus international PAH treatment algorithms; however, there is no published guideline detailing how this intervention should be carried out. Areas covered: This review describes the evidence available and evaluates its applicability to 'real life' clinical practice. The limitations of current evidence are acknowledged, and we discuss how the existing data can be applied to management of PAH patients in Australia, New Zealand, and countries with similar healthcare systems. Recommendations for PAH exercise training are proposed including patient selection, program structure and duration, training modalities, training intensity, supervision, monitoring, safety precautions, and outcome assessments. Expert commentary: It is recognized that knowledge gaps remain and further research is required into physiological mechanisms associated with improved exercise capacity, optimal outpatient exercise regimen, durability of benefit, and whether there is any disease-modifying effect or impact on long-term prognosis.

Increasing quality of life in pulmonary arterial hypertension: is there a role for nutrition?

Pulmonary arterial hypertension (PAH) is a progressive disease primarily affecting the pulmonary vasculature and heart. PAH patients suffer from exercise intolerance and fatigue, negatively affecting their quality of life. This review summarizes current insights in the pathophysiological mechanisms underlying PAH. It zooms in on the potential involvement of nutritional status and micronutrient deficiencies on PAH exercise intolerance and fatigue, also summarizing the potential benefits of exercise and nutritional interventions. Pubmed/Medline, Scopus, and Web of Science were searched for publications on pathophysiological mechanisms of PAH negatively affecting physical activity potential and nutritional status, and for potential effects of interventions involving exercise or nutritional measures known to improve exercise intolerance. Pathophysiological processes that contribute to exercise intolerance and impaired quality of life of PAH patients include right ventricular dysfunction, inflammation, skeletal muscle alterations, and dysfunctional energy metabolism. PAH-related nutritional deficiencies and metabolic alterations have been linked to fatigue, exercise intolerance, and endothelial dysfunction. Available evidence suggests that exercise interventions can be effective in PAH patients to improve exercise tolerance and decrease fatigue. By contrast, knowledge on the prevalence of micronutrient deficiencies and the possible effects of nutritional interventions in PAH patients is limited. Although data on nutritional status and micronutrient deficiencies in PAH are scarce, the available knowledge, including that from adjacent fields, suggests that nutritional intervention to correct deficiencies and metabolic alterations may contribute to a reduction of disease burden.

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.

Exercise-based evaluations and interventions for pulmonary hypertension with connective tissue disorders

INTRODUCTION

Exercise intolerance is a common and often significant limitation in pulmonary arterial hypertension (PAH). This intolerance greatly affects the quality of life and function of the individual with PAH, irrespective of its etiology. In PAH associated with connective tissue disorders (PAH-CTD), exercise intolerance is further amplified by the presence of coexisting musculoskeletal manifestations of CTD. The evaluation of exercise capacity and prescription for exercise training therefore becomes a challenge to the clinician. Areas covered: This review highlights factors contributing to exercise intolerance in PAH-CTD, evaluation methods of exercise capacity and an overview on exercise training and a roadmap for future research. Expert commentary: Exercise intolerance is a complex interplay of cardiovascular, pulmonary, and musculoskeletal systems. Data from cardiopulmonary exercise tests have shown predictive abilities for both diagnosis and prognosis. In its absence, the 6-min walk test can be used to provide similar information thereby making the role of exercise testing an invaluable evaluation method in PAH-CTD. Exercise training data in PAH-CTD are still sparse, though, data from PAH studies suggest potential benefit. However, more research is required in this area of testing and training for greater understanding on exercise hemodynamic, phenotypes, and training benefits.

Comorbidities in Patients With Chronic Obstructive Pulmonary Disease and Pulmonary Rehabilitation Outcomes

PURPOSE

The objective of this study was to evaluate the impact of comorbidities as potential predictors of the response to pulmonary rehabilitation in patients with chronic obstructive pulmonary disease (COPD).

METHODS

The study included 165 patients with COPD with exercise limitations. Comorbidity was classified as cardiac, metabolic, orthopedic, behavioral health problems, or other diseases. Number of comorbidities was grouped as 0, 1, or ≥2. Outcomes were defined as improvement in exercise capacity (maximal exercise capacity, 6-minute walk test, and constant workload cycle exercise duration) and quality of life (Chronic Respiratory Questionnaire). We assessed the effect of comorbidities on improvement in outcomes and the impact of the number of comorbidities on the percentage of patients reaching the minimal clinically important difference for each outcome.

RESULTS

Most patients (n = 160; 96%) were elderly males (mean age 70 years) with COPD Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages II to IV. Sixty-four percent of patients had at least 1 comorbidity. The ≥2 comorbidity group (n = 29) had a higher modified Charlson index and more patients required continuous supplemental oxygen. Absolute differences in dyspnea scores in patients with cardiac disease and orthopedic problems compared with those without these comorbidities were 2.6 ± 0.87; 95% CI 0.89 to 4.32; p = .003, and -3.25 ± 1.23; 95% CI -5.69 to -0.82; p = .009, respectively. Comorbidities had no significant effect on other exercise outcomes or quality of life.

CONCLUSION

Patients with cardiac disease experienced greater improvement in the dyspnea score compared with patients with no cardiac disease, whereas patients with orthopedic problems had a smaller but also clinically significant improvement in dyspnea after pulmonary rehabilitation.

Study protocol for a randomised controlled trial of exercise training in pulmonary hypertension (ExTra_PH)

Background

Exercise training is an integral component of evidence-based management programs for many chronic cardiac and respiratory conditions. Despite this, there are limited high-quality studies available on the significance of exercise training in pulmonary hypertension (PH). The aim of this study is to evaluate the short and long-term effectiveness of exercise training in PH patients in terms of exercise capacity, quality of life, cardiac function and disease progression.

Methods

This randomized control trial will aim to recruit 50 medically stable PH patients categorised as New York Heart Association functional classification II-III. Participants will be randomly allocated to either the supervised exercise training group or usual care group for the 8-week study period. Exercise training will be conducted in an outpatient setting. Measurements at baseline and following the 8-week study period include exercise capacity (6 min walk distance and cardiopulmonary exercise test), cardiac function (exercise cardiac magnetic resonance imaging [CMRI] and echocardiography), health-related quality of life (Cambridge Pulmonary Hypertension Outcome Review), adverse responses to exercise training and time to clinical worsening. In addition, participants will be followed up for a minimum of 2 year period from commencement of the study so as to monitor long-term clinical outcomes i.e. time to clinical worsening.

Discussion

This study will determine whether an 8-week outpatient based supervised exercise training program is safe and beneficial for medically stable PH patients in the short and long term. This will be the first study to examine the impact of exercise training on right heart function using exercise CMRI. Results from the study will contribute new knowledge in relation to the impact of exercise training on cardiac function, long-term prognosis and inform clinical practice guidelines for this patient population. Moreover, the study will add to our understanding regarding the efficacy of exercise training in individuals with PH in an outpatient setting.

Trial registration

Australia and New Zealand Clinical Trials Registry: ACTRN12616001467426. Registered 21st October, 2016.

Exercise training in patients with pulmonary and systemic hypertension: A unique therapy for two different diseases

Pulmonary hypertension is a potentially life-threatening condition. Given its evolving definition, the incidence and prevalence of the disease is difficult to define, but registries suggest an increased global awareness. The management of patients with pulmonary arterial hypertension is highly specialised and requires multi-disciplinary input from a range of healthcare professionals, including cardiologists, respiratory physicians, rheumatologists, rehabilitation physicians and cardio-pulmonary physiotherapists. Historically, exercise training in pulmonary hypertension has not been recommended because of safety concerns. However, an increasing number of studies have demonstrated the benefit of exercise training on exercise capacity, peak oxygen consumption and quality of life. Systemic hypertension is one of the most important risk factors for cardiovascular disease, and has been ranked as the leading cause for death and disability worldwide: therefore, adequate control of blood pressure is important for public health. Lowering of blood pressure and prevention of hypertension is in first instance preferable by lifestyle changes. These include weight loss, moderation of alcohol intake, a diet with increased fresh fruit and vegetables, reduced saturated fat, reduced salt intake, reduced stress, and, finally, increased physical activity. With regard to the latter, former guidelines predominantly recommended aerobic exercises such as walking, jogging, and cycling for lowering blood pressure. The main focus of this narrative overview paper is to briefly examine and summarize the benefit of exercise training in patients with pulmonary and systemic hypertension, suggest mechanisms by which exercise may improve symptoms and function and provide evidence-based recommendations regarding the frequency and intensity of exercise in these patients.

Exercise training in pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is characterized by a continuous increase in pre-capillary pulmonary vascular resistance (PVR) with a progressive reduction of cardiac output (CO). Similar to what occurs in left heart failure (HF), this represents the initial phase of a syndrome characterized by the progressive development of dyspnea and fatigue with increasing deterioration of exercise tolerance. Although the therapies introduced in the last two decades have determined a significant improvement of the clinical conditions of PAH patients, they have a little impact on exercise capacity and prognosis. However, as previously demonstrated for HF, recent pilot studies have reported that physical and respiratory rehabilitation may have a specific role in the management of PAH. Despite potential risks, so far all studies agree that exercise training (ET) improves exercise capacity, quality of life (QoL), muscle function and pulmonary circulation. We will review the pathophysiological mechanisms underlying the functional incompetence of PAH patients, the effects of ET on clinical and functional parameters, the selection criteria for inclusion of patients in a training program, the suggested monitoring of beneficial effects or possible side effects induced by ET. Finally, we discuss of the possible exercise induced amelioration of prognosis in PAH.

Pulmonary arterial hypertension: tailoring treatment to risk in the current era

Recent advances in the treatment of pulmonary arterial hypertension (PAH) have led to improved patient outcomes. Multiple PAH therapies are now available and optimising the use of these drugs in clinical practice is vital. In this review, we discuss the management of PAH patients in the context of current treatment guidelines and supporting clinical evidence. In clinical practice, considerable emphasis is placed on the importance of making treatment decisions guided by each patient's risk status, which should be assessed using multiple prognostic parameters. As PAH is a progressive disease, regular assessments are essential to ensure that any change in risk is detected in a timely manner and treatment is adjusted accordingly. With the availability of therapies that target three different pathogenic pathways, combination therapy is now the standard of care. For most patients, this involves dual combination therapy with agents targeting the endothelin and nitric oxide pathways. Therapies targeting the prostacyclin pathway should be added for patients receiving dual combination therapy who do not achieve a low-risk status. There is also a need for a holistic approach to treatment beyond pharmacological therapies. Implementation of all these approaches will ensure that PAH patients receive maximal benefit from currently available therapies.

Optimal PAH treatment requires frequent multiparameter risk assessment and early initiation of combination therapyhttp://ow.ly/IA6t30fPceT

A prescribed walking regimen plus arginine supplementation improves function and quality of life for patients with pulmonary arterial hypertension: a pilot study

Current evidence suggests that exercise training is beneficial in pulmonary arterial hypertension (PAH). Unfortunately, the standard supervised, hospital-based programs limit patient accessibility to this important intervention. Our proof-of-concept study aimed to provide insight into the usefulness of a prescribed walking regimen along with arginine supplementation to improve outcomes for patients with PAH. Twelve PAH patients (all women) in New York Heart Association (NYHA) functional class (FC) II (n = 7) or III (n = 5) and in stable condition for ≥ 3 months were enrolled. Patients performed home- and fitness-center- based walking at 65-75% heart rate (HR) reserve for 45 min, six sessions/week for 12 weeks. Concomitant L-arginine supplementation (6000 mg/day) was provided to maximize beneficial endothelial training adaptations. Cardiopulmonary exercise testing, 6-min walk testing (6MWT), echocardiography, laboratory studies, and quality of life (QoL) survey (SF-36) were performed at baseline and 12 weeks. Eleven patients completed the study (72 session adherence rate = 96 ± 3%). Objective improvement was demonstrated by the 6MWT distance (increased by 40 ± 13 m, P = 0.01), VO₂max (increased by 2 ± 0.7 mL/kg/min, P = 0.02), time-to-VO₂max (increased by 2.5 ± 0.6 min, P = 0.001), VO₂ at anaerobic threshold (increased by 1.3 ± 0.5 mL/kg/min, P = 0.04), HR recovery (reduced by 68 ± 23% in slope, P = 0.01), and SF-36 subscales of Physical Functioning and Energy/Fatigue (increased by 70 ± 34% and 74 ± 34%, respectively, P < 0.05). No adverse events occurred, and right ventricular function and brain natriuretic peptide levels remained stable, suggesting safety of the intervention. This proof-of-concept study indicates that a simple walking regimen with arginine supplementation is a safe and efficacious intervention for clinically stable PAH patients, with gains in objective function and QoL measures. Further investigation in a randomized controlled trial is warranted.

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

Pulmonary hypertension (PH) is characterized by severe exercise limitation mainly attributed to the impairment of right ventricular function resulting from a concomitant elevation of pulmonary vascular resistance and pressure. The unquestioned cornerstone in the management of patients with pulmonary arterial hypertension (PAH) is specific vasoactive medical therapy to improve pulmonary hemodynamics and strengthen right ventricular function. Nevertheless, evidence for a beneficial effect of exercise training (ET) on pulmonary hemodynamics and functional capacity in patients with PH has been growing during the past decade. Beneficial effects of ET on regulating factors, inflammation, and metabolism have also been described. Small case-control studies and randomized clinical trials in larger populations of patients with PH demonstrated substantial improvements in functional capacity after ET. These findings were accompanied by several studies that suggested an effect of ET on inflammation, although a direct link between this effect and the therapeutic benefit of ET in PH has not yet been demonstrated. On this background, the aim of the present review is to describe current concepts regarding the effects of exercise on the pulmonary circulation and pathophysiological limitations, as well as the clinical and mechanistic effects of exercise in patients with PH.