1
|
Samani SL, Barlow SC, Freeburg LA, Jones TL, Poole M, Sarzynski MA, Zile MR, Shazly T, Spinale FG. Left ventricle function and post-transcriptional events with exercise training in pigs. PLoS One 2024; 19:e0292243. [PMID: 38306359 PMCID: PMC10836705 DOI: 10.1371/journal.pone.0292243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Accepted: 09/14/2023] [Indexed: 02/04/2024] Open
Abstract
BACKGROUND Standardized exercise protocols have been shown to improve overall cardiovascular fitness, but direct effects on left ventricular (LV) function, particularly diastolic function and relation to post-transcriptional molecular pathways (microRNAs (miRs)) are poorly understood. This project tested the central hypothesis that adaptive LV remodeling resulting from a large animal exercise training protocol, would be directly associated with specific miRs responsible for regulating pathways relevant to LV myocardial stiffness and geometry. METHODS AND RESULTS Pigs (n = 9; 25 Kg) underwent a 4 week exercise training protocol (10 degrees elevation, 2.5 mph, 10 min, 5 days/week) whereby LV chamber stiffness (KC) and regional myocardial stiffness (rKm) were measured by Doppler/speckle tracking echocardiography. Age and weight matched non-exercise pigs (n = 6) served as controls. LV KC fell by approximately 50% and rKm by 30% following exercise (both p < 0.05). Using an 84 miR array, 34 (40%) miRs changed with exercise, whereby 8 of the changed miRs (miR-19a, miR-22, miR-30e, miR-99a, miR-142, miR-144, miR-199a, and miR-497) were correlated to the change in KC (r ≥ 0.5 p < 0.05) and mapped to matrix and calcium handling processes. Additionally, miR-22 and miR-30e decreased with exercise and mapped to a localized inflammatory process, the inflammasome (NLRP-3, whereby a 2-fold decrease in NLRP-3 mRNA occurred with exercise (p < 0.05). CONCLUSION Chronic exercise reduced LV chamber and myocardial stiffness and was correlated to miRs that map to myocardial relaxation processes as well as local inflammatory pathways. These unique findings set the stage for utilization of myocardial miR profiling to identify underlying mechanisms by which exercise causes changes in LV myocardial structure and function.
Collapse
Affiliation(s)
- Stephanie L. Samani
- Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC, United States of America
- Columbia VA Health Care System, Columbia, SC, United States of America
| | - Shayne C. Barlow
- Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC, United States of America
| | - Lisa A. Freeburg
- Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC, United States of America
- Columbia VA Health Care System, Columbia, SC, United States of America
| | - Traci L. Jones
- Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC, United States of America
| | - Marlee Poole
- Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC, United States of America
| | - Mark A. Sarzynski
- Department of Exercise Science, Arnold School of Public Health, University of South Carolina, Columbia, SC, United States of America
| | - Michael R. Zile
- Division of Cardiology, RHJ Department of Veterans Affairs Medical Center, Medical University of South Carolina, Charleston, SC, United States of America
| | - Tarek Shazly
- College of Engineering and Computing, University of South Carolina, Columbia, SC, United States of America
| | - Francis G. Spinale
- Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC, United States of America
- Columbia VA Health Care System, Columbia, SC, United States of America
- College of Engineering and Computing, University of South Carolina, Columbia, SC, United States of America
- Cardiovascular Translational Research Center, University of South Carolina, Columbia, SC, United States of America
| |
Collapse
|
2
|
Barret T, Degano B, Bouvaist H, Pison C, Noirclerc M, Vanzetto G, Rocca C. Routine Rehabilitation as a Treatment Component for Patients With Pulmonary Arterial or Chronic Thromboembolic Pulmonary Hypertensions. J Cardiopulm Rehabil Prev 2023; 43:354-360. [PMID: 36939648 DOI: 10.1097/hcr.0000000000000755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/21/2023]
Abstract
PURPOSE Patients with pulmonary hypertension (PH) have long been advised to avoid exercise in fear of deterioration in right-sided heart function. Since the 2009 European Society of Cardiology guidelines, rehabilitation in expert centers is considered to have a specific role in care of patients with pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH). We report routine rehabilitation effects in patients with PH as a component of real-life multimodal treatment. METHODS Patients with PAH or CTEPH were recommended for either in- or outpatient rehabilitation in addition to their usual care, unless there were practical problems or the patient declined. Assessment was conducted according to New York Heart Association classes, adverse events, 6 min-walk test, hemodynamics, and risk stratification after rehabilitation. RESULTS Forty-one patients, 61% female, age 60 ±18 yr were included between March 2010 and May 2019. No major adverse events or deaths related to progression of right-sided heart failure were reported. Nevertheless, 22% of participants suffered adverse events in most cases not linked with physical activity. Rehabilitation as add-on to medical therapy and/or arterial deobstruction improved New York Heart Association class: mean difference, -0.39 (95% CI, -0.68 to -0.10), 6-min walk test: mean difference, 80 m (95% CI, 46-114), and was associated with improved right-sided heart hemodynamics. The risk assessment grade improved by -0.25 points (95% CI, -0.44 to -0.06) after rehabilitation. CONCLUSIONS For patients with PAH or CTEPH, supervised rehabilitation as add-on to medical therapy and/or arterial deobstruction is safe and effective in improving patient and clinically related outcomes.
Collapse
Affiliation(s)
- Thomas Barret
- Service de Rééducation Cardiaque, Institut de Rééducation Sud, Pôle Thorax et Vaisseaux, CHU Grenoble Alpes, Grenoble, France (Drs Barret, Noirclerc, and Rocca); Service de Cardiologie, Pôle Thorax et Vaisseaux, CHU Grenoble Alpes, Grenoble, France (Drs Bouvaist and Vanzetto); Université Grenoble Alpes, Saint-Martin-d'Hères, France (Drs Degano, Pison, and Vanzetto); and Service Hospitalier Universitaire Pneumologie Physiologie, Pôle Thorax et Vaisseaux, CHU Grenoble Alpes, Grenoble, France (Drs Degano and Pison)
| | | | | | | | | | | | | |
Collapse
|
3
|
Morris NR, Kermeen FD, Jones AW, Lee JY, Holland AE. Exercise-based rehabilitation programmes for pulmonary hypertension. Cochrane Database Syst Rev 2023; 3:CD011285. [PMID: 36947725 PMCID: PMC10032353 DOI: 10.1002/14651858.cd011285.pub3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/24/2023]
Abstract
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.
Collapse
Affiliation(s)
- Norman R Morris
- Allied Health Research Collaborative, The Prince Charles Hospital, Chermside, Australia
- School of Allied Health Sciences and Social Work and Menzies Health Institute, Griffith University, Gold Coast Campus, Southport, Australia
| | - Fiona D Kermeen
- Queensland Lung Transplant Service, The Prince Charles Hospital, Brisbane, Australia
| | - Arwel W Jones
- Central Clinical School, Monash University, Melbourne, Australia
| | - Joanna Yt Lee
- Central Clinical School, Monash University, Melbourne, Australia
| | - Anne E Holland
- Central Clinical School, Monash University, Melbourne, Australia
- Physiotherapy, Alfred Health, Melbourne, Australia
- Institute for Breathing and Sleep, Melbourne, Australia
| |
Collapse
|
4
|
Pettersson H, Alexanderson H, Poole JL, Varga J, Regardt M, Russell AM, Salam Y, Jensen K, Mansour J, Frech T, Feghali-Bostwick C, Varjú C, Baldwin N, Heenan M, Fligelstone K, Holmner M, Lammi MR, Scholand MB, Shapiro L, Volkmann ER, Saketkoo LA. Exercise as a multi-modal disease-modifying medicine in systemic sclerosis: An introduction by The Global Fellowship on Rehabilitation and Exercise in Systemic Sclerosis (G-FoRSS). Best Pract Res Clin Rheumatol 2021; 35:101695. [PMID: 34217607 PMCID: PMC8478716 DOI: 10.1016/j.berh.2021.101695] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Systemic sclerosis (SSc) is a heterogeneous multisystem autoimmune disease whereby its main pathological drivers of disability and damage are vascular injury, inflammatory cell infiltration, and fibrosis. These mechanisms result in diffuse and diverse impairments arising from ischemic circulatory dysfunction leading to painful skin ulceration and calcinosis, neurovascular aberrations hindering gastrointestinal (GI) motility, progressive painful, incapacitating or immobilizing effects of inflammatory and fibrotic effects on the lungs, skin, articular and periarticular structures, and muscle. SSc-related impairments impede routine activities of daily living (ADLs) and disrupt three critical life areas: work, family, social/leisure, and also impact on psychological well-being. Physical activity and exercise are globally recommended; however, for connective tissue diseases, this guidance carries greater impact on inflammatory disease manifestations, recovery, and cardiovascular health. Exercise, through myogenic and vascular phenomena, naturally targets key pathogenic drivers by downregulating multiple inflammatory and fibrotic pathways in serum and tissue, while increasing circulation and vascular repair. G-FoRSS, The Global Fellowship on Rehabilitation and Exercise in Systemic Sclerosis recognizes the scientific basis of and advocates for education and research of exercise as a systemic and targeted SSc disease-modifying treatment. An overview of biophysiological mechanisms of physical activity and exercise are herein imparted for patients, clinicians, and researchers, and applied to SSc disease mechanisms, manifestations, and impairment. A preliminary guidance on exercise in SSc, a research agenda, and the current state of research and outcome measures are set forth.
Collapse
Affiliation(s)
- Henrik Pettersson
- Women's Health and Allied Health Professionals, Medical Unit Occupational Therapy and Physiotherapy, Karolinska University Hospital, Stockholm, Sweden; Division of Rheumatology, Department of Medicin, Solna, Karolinska Institutet, Stockholm, Sweden
| | - Helene Alexanderson
- Women's Health and Allied Health Professionals, Medical Unit Occupational Therapy and Physiotherapy, Karolinska University Hospital, Stockholm, Sweden; Division of Rheumatology, Department of Medicin, Solna, Karolinska Institutet, Stockholm, Sweden
| | - Janet L Poole
- Occupational Therapy Graduate Program, University of New Mexico, Albuquerque, NM, USA
| | - Janos Varga
- Department of Pulmonology, Semmelweis University, Budapest, Hungary
| | - Malin Regardt
- Women's Health and Allied Health Professionals, Medical Unit Occupational Therapy and Physiotherapy, Karolinska University Hospital, Stockholm, Sweden; Department of Occupational Therapy, Karolinska Institutet, Stockholm, Sweden
| | - Anne-Marie Russell
- University of Exeter, College of Medicine and Health, Exeter, UK; National Institute of Health Research, Senior Nurse Research Leader, London, UK
| | - Yasser Salam
- Department of Physical Therapy, University of North Texas Health Science Center, Fort Worth, TX, USA
| | - Kelly Jensen
- Oregon Health and Science University, Portland, OR, USA; New Orleans Scleroderma and Sarcoidosis Patient Care and Research Center, New Orleans, USA; Tulane University School of Medicine, New Orleans, USA
| | - Jennifer Mansour
- New Orleans Scleroderma and Sarcoidosis Patient Care and Research Center, New Orleans, USA; Tulane University School of Medicine, New Orleans, USA
| | - Tracy Frech
- Vanderbilt University, Division of Rheumatology, Nashville, TN, USA
| | | | - Cecília Varjú
- Department of Rheumatology and Immunology, University of Pécs Clinical Center, Pecs, Hungary
| | | | - Matty Heenan
- Scleroderma Foundation/Pulmonary Hypertension Association, Tucson, AZ, USA
| | - Kim Fligelstone
- Scleroderma & Raynaud Society UK (SRUK), London, UK; Royal Free Hospital, London, UK
| | - Monica Holmner
- The Swedish Rheumatism Association National Association for Systemic Sclerosis, Sweden
| | - Matthew R Lammi
- New Orleans Scleroderma and Sarcoidosis Patient Care and Research Center, New Orleans, USA; University Medical Center - Comprehensive Pulmonary Hypertension Center and Interstitial Lung Disease Clinic Programs, New Orleans, USA; Louisiana State University School of Medicine, Section of Pulmonary Medicine, New Orleans, USA
| | - Mary Beth Scholand
- University of Utah, Division of Pulmonary Medicine, Pulmonary Fibrosis Center, Salt Lake City, UT, USA
| | - Lee Shapiro
- Division of Rheumatology, Albany Medical Center, Albany, NY, USA; Steffens Scleroderma Foundation, Albany, NY, USA
| | - Elizabeth R Volkmann
- University of California, David Geffen School of Medicine, UCLA Scleroderma Program and UCLA CTD-ILD Program, Division of Rheumatology, Department of Medicine, Los Angeles, CA, USA
| | - Lesley Ann Saketkoo
- New Orleans Scleroderma and Sarcoidosis Patient Care and Research Center, New Orleans, USA; Tulane University School of Medicine, New Orleans, USA; University Medical Center - Comprehensive Pulmonary Hypertension Center and Interstitial Lung Disease Clinic Programs, New Orleans, USA; Louisiana State University School of Medicine, Section of Pulmonary Medicine, New Orleans, USA.
| |
Collapse
|
5
|
Exercise preconditioning prevents left ventricular dysfunction and remodeling in monocrotaline-induced pulmonary hypertension. Porto Biomed J 2020; 5:e081. [PMID: 33195871 PMCID: PMC7657575 DOI: 10.1097/j.pbj.0000000000000081] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 06/25/2020] [Accepted: 06/29/2020] [Indexed: 11/26/2022] Open
Abstract
Background: Despite pulmonary arterial hypertension (PAH) directly affects the right ventricle (RV), important structural, functional, and molecular changes also occur in left ventricle (LV). The objective of our study was to analyze the hypothetical cardioprotective effects of exercise preconditioning on LV in rats with monocrotaline (MCT)-induced PAH. Methods: Forty male Wistar rats were randomly separated in sedentary (SED) and trained group (EX; running sessions of 60 min/day, 5 days/wk, at 25 m/min, for 4 weeks). After 4 weeks, animals were injected with MCT (60 mg/kg; SED + MCT; EX + MCT) or vehicle (SED + V). Following an additional period of 4 weeks where all animals remained sedentary, we completed LV hemodynamic evaluation in baseline and isovolumic conditions and collected LV samples for histological and molecular analysis. Results: Preconditioning with exercise was capable to restore LV systolic and diastolic dysfunction in both baseline and isovolumic conditions (P < .05). This improved was paralleled with prevention of LV cardiomyocytes atrophy, fibrosis, and endothelin 1 mRNA levels (P < .05). Conclusions: Our findings suggest that exercise preconditioning can prevent LV dysfunction secondary to MCT-induced PAH, which is of particular interest for the familial form of the disease that is manifested by greater severity or earlier onset.
Collapse
|
6
|
Waller L, Krüger K, Conrad K, Weiss A, Alack K. Effects of Different Types of Exercise Training on Pulmonary Arterial Hypertension: A Systematic Review. J Clin Med 2020; 9:jcm9061689. [PMID: 32498263 PMCID: PMC7356848 DOI: 10.3390/jcm9061689] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 05/13/2020] [Accepted: 05/26/2020] [Indexed: 12/12/2022] Open
Abstract
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.
Collapse
Affiliation(s)
- Lena Waller
- Department of Exercise Physiology and Sports Therapy, Institute of Sports Sciences, Justus-Liebig-University Giessen, 35394 Giessen, Germany; (K.K.); (K.C.); (K.A.)
- Correspondence: ; Tel.: +49-641-99-25212
| | - Karsten Krüger
- Department of Exercise Physiology and Sports Therapy, Institute of Sports Sciences, Justus-Liebig-University Giessen, 35394 Giessen, Germany; (K.K.); (K.C.); (K.A.)
| | - Kerstin Conrad
- Department of Exercise Physiology and Sports Therapy, Institute of Sports Sciences, Justus-Liebig-University Giessen, 35394 Giessen, Germany; (K.K.); (K.C.); (K.A.)
| | - Astrid Weiss
- Department of Internal Medicine, Institute of Pulmonary Pharmacotherapy, Justus-Liebig-University Giessen, Universities of Giessen and Marburg Lung Center (UGMLC), 35392 Giessen, Germany;
| | - Katharina Alack
- Department of Exercise Physiology and Sports Therapy, Institute of Sports Sciences, Justus-Liebig-University Giessen, 35394 Giessen, Germany; (K.K.); (K.C.); (K.A.)
| |
Collapse
|
7
|
Morris ZV, Chin LMK, Chan L, Guccione AA, Ahmad A, Keyser RE. Cardiopulmonary exercise test indices of respiratory buffering before and after aerobic exercise training in women with pulmonary hypertension: Differentiation by magnitudes of change in six-minute walk test performance. Respir Med 2020; 164:105900. [PMID: 32217288 PMCID: PMC10367185 DOI: 10.1016/j.rmed.2020.105900] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 02/10/2020] [Accepted: 02/11/2020] [Indexed: 02/01/2023]
Abstract
While aerobic exercise training (AET) has generally been shown to improve 6-min walk test (6MWT) distance (6MWD) in patients with pulmonary hypertension (PH), a substantial number of patients appear to adapt differently, with minimal or even negative changes in 6MWT distance being reported. PURPOSE To compare post-aerobic exercise training adaptations in cardiorespiratory functional capacity across three groups of patients with PH: those with high (HI), low (LI) and negative (NEG) post-training increases in 6MWD. METHODS Participants were 25 females (age 54 ± 11 years; BMI 31 ± 7 kg/m2) who completed a vigorous, 10-week, thrice weekly, supervised treadmill walking exercise program. Cardiopulmonary exercise tests (CPET) and 6MWT were completed before and after training. Ten of the 25 participants were classified as HI (range = 47-143 m), 11 were classified as LI (range = 4-37 m) and 4 were classified as NEG (range = -17 to -53 m). RESULTS Peak CPET duration, WR and time to anaerobic threshold (AT) were significantly higher (p < 0.05) after training in both the LI and HI groups but not in the NEG group. There was a significant improvement in VE/VCO2 (p = 0.042), PETCO2 (p = 0.011) and TV (p = 0.050) in the HI group after training, but not in the NEG or LI group. CONCLUSION These findings suggest that sustained ventilatory inefficiency and restricted respiratory buffering may mediate exercise intolerance and impede the ability to adapt to exercise training in some patients with PH.
Collapse
Affiliation(s)
- Z V Morris
- Department of Rehabilitation Science, George Mason University, Fairfax, VA, USA; Rehabilitation Medicine Department, National Institutes of Health Clinical Center, Bethesda, MD, USA
| | - L M K Chin
- Rehabilitation Medicine Department, National Institutes of Health Clinical Center, Bethesda, MD, USA
| | - L Chan
- Rehabilitation Medicine Department, National Institutes of Health Clinical Center, Bethesda, MD, USA
| | - A A Guccione
- Department of Rehabilitation Science, George Mason University, Fairfax, VA, USA
| | - A Ahmad
- Rehabilitation Medicine Department, National Institutes of Health Clinical Center, Bethesda, MD, USA
| | - R E Keyser
- Department of Rehabilitation Science, George Mason University, Fairfax, VA, USA; Rehabilitation Medicine Department, National Institutes of Health Clinical Center, Bethesda, MD, USA.
| |
Collapse
|