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Goh JT, Balmain BN, Tomlinson AR, MacNamara JP, Sarma S, Ritz T, Wakeham DJ, Brazile TL, Hynan LS, Levine BD, Babb TG. Respiratory symptom perception during exercise in patients with heart failure with preserved ejection fraction. Respir Physiol Neurobiol 2024; 325:104256. [PMID: 38583744 PMCID: PMC11088520 DOI: 10.1016/j.resp.2024.104256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 02/26/2024] [Accepted: 04/04/2024] [Indexed: 04/09/2024]
Abstract
We investigated whether central or peripheral limitations to oxygen uptake elicit different respiratory sensations and whether dyspnea on exertion (DOE) provokes unpleasantness and negative emotions in patients with heart failure with preserved ejection fraction (HFpEF). 48 patients were categorized based on their cardiac output (Q̇c)/oxygen uptake (V̇O2) slope and stroke volume (SV) reserve during an incremental cycling test. 15 were classified as centrally limited and 33 were classified as peripherally limited. Ratings of perceived breathlessness (RPB) and unpleasantness (RPU) were assessed (Borg 0-10 scale) during a 20 W cycling test. 15 respiratory sensations statements (1-10 scale) and 5 negative emotions statements (1-10) were subsequently rated. RPB (Central: 3.5±2.0 vs. Peripheral: 3.4±2.0, p=0.86), respiratory sensations, or negative emotions were not different between groups (p>0.05). RPB correlated (p<0.05) with RPU (r=0.925), "anxious" (r=0.610), and "afraid" (r=0.383). While DOE provokes elevated levels of negative emotions, DOE and respiratory sensations seem more related to a common mechanism rather than central and/or peripheral limitations in HFpEF.
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Affiliation(s)
- Josh T Goh
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, TX, USA; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Bryce N Balmain
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, TX, USA; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Andrew R Tomlinson
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, TX, USA; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - James P MacNamara
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, TX, USA; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Satyam Sarma
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, TX, USA; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Thomas Ritz
- Department of Psychology, Southern Methodist University, Dallas, TX, USA
| | - Denis J Wakeham
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, TX, USA; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Tiffany L Brazile
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, TX, USA; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Linda S Hynan
- The O'Donnell School of Public Health and Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Benjamin D Levine
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, TX, USA; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Tony G Babb
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, TX, USA; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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2
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Haverkamp HC, Balmain BN. Ventilatory Responses to Exercise by Age, Sex, and Health Status. Curr Sports Med Rep 2024; 23:79-85. [PMID: 38437493 DOI: 10.1249/jsr.0000000000001149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2024]
Abstract
ABSTRACT An understanding of the normal pulmonary responses to incremental exercise is requisite for appropriate interpretation of findings from clinical exercise testing. The purpose of this review is to provide concrete information to aid the interpretation of the exercise ventilatory response in both healthy and diseased populations. We begin with an overview of the normal exercise ventilatory response to incremental exercise in the healthy, normally trained young-to-middle aged adult male. The exercise ventilatory responses in two nonpatient populations (females, elderly) are then juxtaposed with the responses in healthy males. The review concludes with overviews of the exercise ventilatory responses in four patient populations (obesity, chronic obstructive pulmonary disease, asthma, congestive heart failure). Again, we use the normal response in healthy adults as the framework for interpreting the responses in the clinical groups. For each healthy and clinical population, recent, impactful research findings will be presented.
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Affiliation(s)
- Hans Christian Haverkamp
- Department of Nutrition and Exercise Physiology, Elson S. Floyd College of Medicine, Washington State University-Spokane Health Sciences, Spokane, WA
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3
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Goh JT, Balmain BN, Wilhite DP, Granados J, Sandy LL, Liu YL, Pawelczyk JA, Babb TG. Elevated risk of dyspnea in adults with obesity. Respir Physiol Neurobiol 2023; 318:104151. [PMID: 37673304 PMCID: PMC11087888 DOI: 10.1016/j.resp.2023.104151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 08/24/2023] [Accepted: 09/03/2023] [Indexed: 09/08/2023]
Abstract
We investigated whether older adults (OA) with obesity are more likely to have dyspnea compared with OA without obesity, and whether OA with obesity are at a greater risk of having dyspnea compared with middle-aged (MA) and younger adults (YA) with obesity. We obtained de-identified data from the TriNetX UT Southwestern Medical Center database. We identified obesity and dyspnea using ICD-10-CM codes E66 and R06.0, respectively. Patients were separated into three age groups: OA, (65-75 y.o.), MA (45-55 y.o.), and YA (25-35 y.o). Within these groups, those with and without obesity or dyspnea were identified for analysis. The risk of dyspnea was greater in OA (risk ratio: 3.64), MA (risk ratio: 3.52), and YA (risk ratio: 2.76) with obesity compared with age-matched patients without obesity (all p < 0.01). The risk of dyspnea was greater in OA and MA with obesity compared with YA with obesity (both p < 0.001 vs. YA). These findings suggest that clinicians should consider obesity as an independent risk factor for dyspnea.
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Affiliation(s)
- Josh T Goh
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, and University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Bryce N Balmain
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, and University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Daniel P Wilhite
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, and University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Jorge Granados
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, and University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Lydia L Sandy
- Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Yu-Lun Liu
- Peter O'Donnell Jr. School of Public Health, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - James A Pawelczyk
- Noll Laboratory, Department of Kinesiology, Pennsylvania State University, University Park, PA, USA
| | - Tony G Babb
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, and University of Texas Southwestern Medical Center, Dallas, TX, USA.
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Berton DC, Plachi F, James MD, Vincent SG, Smyth RM, Domnik NJ, Phillips DB, de-Torres JP, Nery LE, O'Donnell DE, Neder JA. Dynamic Ventilatory Reserve During Incremental Exercise: Reference Values and Clinical Validation in Chronic Obstructive Pulmonary Disease. Ann Am Thorac Soc 2023; 20:1425-1434. [PMID: 37413694 DOI: 10.1513/annalsats.202304-303oc] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 07/06/2023] [Indexed: 07/08/2023] Open
Abstract
Rationale: Ventilatory demand-capacity imbalance, as inferred based on a low ventilatory reserve, is currently assessed only at peak cardiopulmonary exercise testing (CPET). Peak ventilatory reserve, however, is poorly sensitive to the submaximal, dynamic mechanical ventilatory abnormalities that are key to dyspnea genesis and exercise intolerance. Objectives: After establishing sex- and age-corrected norms for dynamic ventilatory reserve at progressively higher work rates, we compared peak and dynamic ventilatory reserve for their ability to expose increased exertional dyspnea and poor exercise tolerance in mild to very severe chronic obstructive pulmonary disease (COPD). Methods: We analyzed resting functional and incremental CPET data from 275 controls (130 men, aged 19-85 yr) and 359 Global Initiative for Chronic Obstructive Lung Disease patients with stage 1-4 obstruction (203 men) who were prospectively recruited for previous ethically approved studies in three research centers. In addition to peak and dynamic ventilatory reserve (1 - [ventilation / estimated maximal voluntary ventilation] × 100), operating lung volumes and dyspnea scores (0-10 on the Borg scale) were obtained. Results: Dynamic ventilatory reserve was asymmetrically distributed in controls; thus, we calculated its centile distribution at every 20 W. The lower limit of normal (lower than the fifth centile) was consistently lower in women and older subjects. Peak and dynamic ventilatory reserve disagreed significantly in indicating an abnormally low test result in patients: whereas approximately 50% of those with a normal peak ventilatory reserve showed a reduced dynamic ventilatory reserve, the opposite was found in approximately 15% (P < 0.001). Irrespective of peak ventilatory reserve and COPD severity, patients who had a dynamic ventilatory reserve below the lower limit of normal at an isowork rate of 40 W had greater ventilatory requirements, prompting earlier attainment of critically low inspiratory reserve. Consequently, they reported higher dyspnea scores, showing poorer exercise tolerance compared with those with preserved dynamic ventilatory reserve. Conversely, patients with preserved dynamic ventilatory reserve but reduced peak ventilatory reserve reported the lowest dyspnea scores, showing the best exercise tolerance. Conclusions: Reduced submaximal dynamic ventilatory reserve, even in the setting of preserved peak ventilatory reserve, is a powerful predictor of exertional dyspnea and exercise intolerance in COPD. This new parameter of ventilatory demand-capacity mismatch may enhance the yield of clinical CPET in the investigation of activity-related breathlessness in individual patients with COPD and other prevalent cardiopulmonary diseases.
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Affiliation(s)
- Danilo C Berton
- Unidade de Fisiologia Pulmonar, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Franciele Plachi
- Unidade de Fisiologia Pulmonar, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Matthew D James
- Respiratory Investigation Unit, Division of Respirology, Department of Medicine, Kingston Health Sciences Centre, Queen's University and Kingston General Hospital, Kingston, Ontario, Canada
| | - Sandra G Vincent
- Respiratory Investigation Unit, Division of Respirology, Department of Medicine, Kingston Health Sciences Centre, Queen's University and Kingston General Hospital, Kingston, Ontario, Canada
| | - Reginald M Smyth
- Respiratory Investigation Unit, Division of Respirology, Department of Medicine, Kingston Health Sciences Centre, Queen's University and Kingston General Hospital, Kingston, Ontario, Canada
| | - Nicolle J Domnik
- Respiratory Investigation Unit, Division of Respirology, Department of Medicine, Kingston Health Sciences Centre, Queen's University and Kingston General Hospital, Kingston, Ontario, Canada
| | - Devin B Phillips
- Respiratory Investigation Unit, Division of Respirology, Department of Medicine, Kingston Health Sciences Centre, Queen's University and Kingston General Hospital, Kingston, Ontario, Canada
- School of Kinesiology and Health Science, Faculty of Health, York University, Toronto, Ontario, Canada; and
| | - Juan P de-Torres
- Respiratory Investigation Unit, Division of Respirology, Department of Medicine, Kingston Health Sciences Centre, Queen's University and Kingston General Hospital, Kingston, Ontario, Canada
| | - Luiz E Nery
- Setor de Função Pulmonar e Fisiologia Clinica do Exercício, Universidade Federal de Sao Paulo, Sao Paulo, Brazil
| | - Denis E O'Donnell
- Respiratory Investigation Unit, Division of Respirology, Department of Medicine, Kingston Health Sciences Centre, Queen's University and Kingston General Hospital, Kingston, Ontario, Canada
| | - J Alberto Neder
- Respiratory Investigation Unit, Division of Respirology, Department of Medicine, Kingston Health Sciences Centre, Queen's University and Kingston General Hospital, Kingston, Ontario, Canada
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Balmain BN, Tomlinson AR, MacNamara JP, Hynan LS, Wakeham DJ, Levine BD, Sarma S, Babb TG. Reducing Pulmonary Capillary Wedge Pressure During Exercise Exacerbates Exertional Dyspnea in Patients With Heart Failure With Preserved Ejection Fraction: Implications for V˙/Q˙ Mismatch. Chest 2023; 164:686-699. [PMID: 37030529 PMCID: PMC10548458 DOI: 10.1016/j.chest.2023.04.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 03/29/2023] [Accepted: 04/01/2023] [Indexed: 04/09/2023] Open
Abstract
BACKGROUND The primary cause of dyspnea on exertion in heart failure with preserved ejection fraction (HFpEF) is presumed to be the marked rise in pulmonary capillary wedge pressure during exercise; however, this hypothesis has never been tested directly. Therefore, we evaluated invasive exercise hemodynamics and dyspnea on exertion in patients with HFpEF before and after acute nitroglycerin (NTG) treatment to lower pulmonary capillary wedge pressure. RESEARCH QUESTION Does reducing pulmonary capillary wedge pressure during exercise with NTG improve dyspnea on exertion in HFpEF? STUDY DESIGN AND METHODS Thirty patients with HFpEF performed two invasive 6-min constant-load cycling tests (20 W): one with placebo (PLC) and one with NTG. Ratings of perceived breathlessness (0-10 scale), pulmonary capillary wedge pressure (right side of heart catheter), and arterial blood gases (radial artery catheter) were measured. Measurements of V˙/Q˙ matching, including alveolar dead space (Vdalv; Enghoff modification of the Bohr equation) and the alveolar-arterial Po2 difference (A-aDO2; alveolar gas equation), were also derived. The ventilation (V˙e)/CO2 elimination (V˙co2) slope was also calculated as the slope of the V˙e and V˙co2 relationship, which reflects ventilatory efficiency. RESULTS Ratings of perceived breathlessness increased (PLC: 3.43 ± 1.94 vs NTG: 4.03 ± 2.18; P = .009) despite a clear decrease in pulmonary capillary wedge pressure at 20 W (PLC: 19.7 ± 8.2 vs NTG: 15.9 ± 7.4 mm Hg; P < .001). Moreover, Vdalv (PLC: 0.28 ± 0.07 vs NTG: 0.31 ± 0.08 L/breath; P = .01), A-aDO2 (PLC: 19.6 ± 6.7 vs NTG: 21.1 ± 6.7; P = .04), and V˙e/V˙co2 slope (PLC: 37.6 ± 5.7 vs NTG: 40.2 ± 6.5; P < .001) all increased at 20 W after a decrease in pulmonary capillary wedge pressure. INTERPRETATION These findings have important clinical implications and indicate that lowering pulmonary capillary wedge pressure does not decrease dyspnea on exertion in patients with HFpEF; rather, lowering pulmonary capillary wedge pressure exacerbates dyspnea on exertion, increases V˙/Q˙ mismatch, and worsens ventilatory efficiency during exercise in these patients. This study provides compelling evidence that high pulmonary capillary wedge pressure is likely a secondary phenomenon rather than a primary cause of dyspnea on exertion in patients with HFpEF, and a new therapeutic paradigm is needed to improve symptoms of dyspnea on exertion in these patients.
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Affiliation(s)
- Bryce N Balmain
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, University of Texas Southwestern Medical Center, Dallas, TX; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX
| | - Andrew R Tomlinson
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, University of Texas Southwestern Medical Center, Dallas, TX; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX
| | - James P MacNamara
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, University of Texas Southwestern Medical Center, Dallas, TX; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX
| | - Linda S Hynan
- The O'Donnell School of Public Health and Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX
| | - Denis J Wakeham
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, University of Texas Southwestern Medical Center, Dallas, TX; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX
| | - Benjamin D Levine
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, University of Texas Southwestern Medical Center, Dallas, TX; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX
| | - Satyam Sarma
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, University of Texas Southwestern Medical Center, Dallas, TX; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX
| | - Tony G Babb
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, University of Texas Southwestern Medical Center, Dallas, TX; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX.
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6
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Foster J, Balmain BN, Wilhite DP, Watso JC, Babb TG, Cramer MN, BelvaL LN, Crandall CG. Inhibiting regional sweat evaporation modifies the ventilatory response to exercise: interactions between core and skin temperature. J Appl Physiol (1985) 2023; 134:1011-1021. [PMID: 36892886 PMCID: PMC10110718 DOI: 10.1152/japplphysiol.00597.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 02/27/2023] [Accepted: 03/03/2023] [Indexed: 03/10/2023] Open
Abstract
In humans, elevated body temperatures can markedly increase the ventilatory response to exercise. However, the impact of changing the effective body surface area (BSA) for sweat evaporation (BSAeff) on such responses is unclear. Ten healthy adults (9 males, 1 female) performed eight exercise trials cycling at 6 W/kg of metabolic heat production for 60 min. Four conditions were used where BSAeff corresponded to 100%, 80%, 60%, and 40% of BSA using vapor-impermeable material. Four trials (one at each BSAeff) were performed at 25°C air temperature, and four trials (one at each BSAeff) at 40°C air temperature, each with 20% humidity. The slope of the relation between minute ventilation and carbon dioxide elimination (V̇E/V̇co2 slope) assessed the ventilatory response. At 25°C, the V̇E/V̇co2 slope was elevated by 1.9 and 2.6 units when decreasing BSAeff from 100 to 80 and to 40% (P = 0.033 and 0.004, respectively). At 40°C, V̇E/V̇co2 slope was elevated by 3.3 and 4.7 units, when decreasing BSAeff from 100 to 60 and to 40% (P = 0.016 and P < 0.001, respectively). Linear regression analyses using group average data from each condition demonstrated that end-exercise mean body temperature (integration of core and mean skin temperature) was better associated with the end-exercise ventilatory response, compared with core temperature alone. Overall, we show that impeding regional sweat evaporation increases the ventilatory response to exercise in temperate and hot environmental conditions, and the effect is mediated primarily by increases in mean body temperature.NEW & NOTEWORTHY Exercise in the heat increases the slope of the relation between minute ventilation and carbon dioxide elimination (V̇E/V̇co2 slope) in young healthy adults. An indispensable role for skin temperature in modulating the ventilatory response to exercise is noted, contradicting common belief that internal/core temperature acts independently as a controller of ventilation during hyperthermia.
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Affiliation(s)
- Josh Foster
- Thermal and Vascular Physiology Laboratory, Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, and University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Bryce N Balmain
- Pulmonary Physiology Laboratory, Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, and University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Daniel P Wilhite
- Pulmonary Physiology Laboratory, Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, and University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Joseph C Watso
- Thermal and Vascular Physiology Laboratory, Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, and University of Texas Southwestern Medical Center, Dallas, Texas, United States
- Cardiovascular and Applied Physiology Laboratory, Department of Nutrition & Integrative Physiology, Florida State University, Tallahassee, Florida, United States
| | - Tony G Babb
- Pulmonary Physiology Laboratory, Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, and University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Matthew N Cramer
- Thermal and Vascular Physiology Laboratory, Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, and University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Luke N BelvaL
- Thermal and Vascular Physiology Laboratory, Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, and University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Craig G Crandall
- Thermal and Vascular Physiology Laboratory, Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, and University of Texas Southwestern Medical Center, Dallas, Texas, United States
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7
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Müller PDT, Chiappa GR, Laveneziana P, Ewert R, Neder JA. Lung mechanical constraints: the Achilles' heel of excess exertional ventilation for prognosis assessment? J Appl Physiol (1985) 2023; 134:378-382. [PMID: 36227163 DOI: 10.1152/japplphysiol.00059.2022] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Affiliation(s)
- Paulo de Tarso Müller
- Laboratory of Respiratory Pathophysiology (LAFIR), Federal University of Mato Grosso do Sul (UFMS)/Maria Aparecida Pedrossian Hospital (HUMAP), Campo Grande, Brazil
| | - Gaspar Rogério Chiappa
- Graduate Program in Human Movement and Rehabilitation of Evangelical Universitary of Goiás, Goiania, Brazil
| | - Pierantonio Laveneziana
- INSERM, UMRS1158 Neurophysiologie Respiratoire Expérimentale et Clinique, Sorbonne Université, Paris, France.,AP-HP, Groupe Hospitalier Universitaire APHP-Sorbonne Université, sites Pitié-Salpêtrière, Saint-Antoine et Tenon, Service des Explorations Fonctionnelles de la Respiration, de l'Exercice et de la Dyspnée (Département R3S), Paris, France
| | - Ralf Ewert
- Department of Internal Medicine B, University Medicine Greifswald, Greifswald, Germany
| | - José Alberto Neder
- Laboratory of Clinical Exercise Physiology and Respiratory Investigation Unit, Queen's University & Kingston General Hospital, Kingston, Ontario, Canada
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8
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Wang CJ, Noble PB, Elliot JG, James AL, Wang KCW. From Beneath the Skin to the Airway Wall: Understanding the Pathological Role of Adipose Tissue in Comorbid Asthma-Obesity. Compr Physiol 2023; 13:4321-4353. [PMID: 36715283 DOI: 10.1002/cphy.c220011] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
This article provides a contemporary report on the role of adipose tissue in respiratory dysfunction. Adipose tissue is distributed throughout the body, accumulating beneath the skin (subcutaneous), around organs (visceral), and importantly in the context of respiratory disease, has recently been shown to accumulate within the airway wall: "airway-associated adipose tissue." Excessive adipose tissue deposition compromises respiratory function and increases the severity of diseases such as asthma. The mechanisms of respiratory impairment are inflammatory, structural, and mechanical in nature, vary depending on the anatomical site of deposition and adipose tissue subtype, and likely contribute to different phenotypes of comorbid asthma-obesity. An understanding of adipose tissue-driven pathophysiology provides an opportunity for diagnostic advancement and patient-specific treatment. As an exemplar, the potential impact of airway-associated adipose tissue is highlighted, and how this may change the management of a patient with asthma who is also obese. © 2023 American Physiological Society. Compr Physiol 13:4321-4353, 2023.
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Affiliation(s)
- Carolyn J Wang
- School of Human Sciences, The University of Western Australia, Crawley, Western Australia, Australia
| | - Peter B Noble
- School of Human Sciences, The University of Western Australia, Crawley, Western Australia, Australia
| | - John G Elliot
- School of Human Sciences, The University of Western Australia, Crawley, Western Australia, Australia.,Department of Pulmonary Physiology and Sleep Medicine, West Australian Sleep Disorders Research Institute, Sir Charles Gairdner Hospital, Nedlands, Western Australia, Australia
| | - Alan L James
- Department of Pulmonary Physiology and Sleep Medicine, West Australian Sleep Disorders Research Institute, Sir Charles Gairdner Hospital, Nedlands, Western Australia, Australia.,Medical School, The University of Western Australia, Nedlands, Western Australia, Australia
| | - Kimberley C W Wang
- School of Human Sciences, The University of Western Australia, Crawley, Western Australia, Australia.,Telethon Kids Institute, The University of Western Australia, Nedlands, Western Australia, Australia
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A Human Model of the Effects of an Instant Sheer Weight Loss on Cardiopulmonary Parameters during a Treadmill Run. J Clin Med 2022; 12:jcm12010098. [PMID: 36614900 PMCID: PMC9821056 DOI: 10.3390/jcm12010098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 12/19/2022] [Accepted: 12/20/2022] [Indexed: 12/24/2022] Open
Abstract
Exercise tolerance is limited in obesity and improves after weight reduction; therefore, we mutually compared the relative changes in exercise capacity variables during cardiopulmonary exercise tests (CPET) in a 12 kg sheer weight reduction model. Twenty healthy male runners underwent two CPETs: CPET1 with the actual body weight, which determined the anaerobic threshold (AT) and respiratory compensation point (RCP); and CPET2 during which the participants wore a +12 kg vest and ran at the AT speed set during the CPET1. Running after body weight reduction shifted the CPET parameters from the high-mixed aerobic-anaerobic (RCP) to the aerobic zone (AT), but these relative changes were not mutually similar. The most beneficial changes were found for breathing mechanics parameters (range 12-28%), followed by cardiovascular function (6-7%), gas exchange (5-6%), and the smallest for the respiratory exchange ratio (5%) representing the energy metabolism during exercise. There was no correlation between the extent of the relative body weight change (median value ~15%) and the changes in CPET parameters. Weight reduction improves exercise capacity and tolerance. However, the observed relative changes are not related to the magnitude of the body change nor comparable between various parameters characterizing the pulmonary and cardiovascular systems and energy metabolism.
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10
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Use of Positive Airway Pressure in the Treatment of Hypoventilation. Sleep Med Clin 2022; 17:577-586. [DOI: 10.1016/j.jsmc.2022.07.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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11
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Balmain BN, Tomlinson AR, MacNamara JP, Hynan LS, Levine BD, Sarma S, Babb TG. Alveolar Dead Space Is Augmented During Exercise in Patients With Heart Failure With Preserved Ejection Fraction. Chest 2022; 162:1349-1359. [PMID: 35753384 PMCID: PMC10403624 DOI: 10.1016/j.chest.2022.06.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 06/09/2022] [Accepted: 06/09/2022] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Patients with heart failure with preserved ejection fraction (HFpEF) exhibit many cardiopulmonary abnormalities that could result in V˙/Q˙ mismatch, manifesting as an increase in alveolar dead space (VDalveolar) during exercise. Therefore, we tested the hypothesis that VDalveolar would increase during exercise to a greater extent in patients with HFpEF compared with control participants. RESEARCH QUESTION Do patients with HFpEF develop VDalveolar during exercise? STUDY DESIGN AND METHODS Twenty-three patients with HFpEF and 12 control participants were studied. Gas exchange (ventilation [V˙E], oxygen uptake [V˙o2], and CO2 elimination [V˙co2]) and arterial blood gases were analyzed at rest, twenty watts (20W), and peak exercise. Ventilatory efficiency (evaluated as the V˙E/V˙co2 slope) also was measured from rest to 20W in patients with HFpEF. The physiologic dead space (VDphysiologic) to tidal volume (VT) ratio (VD/VT) was calculated using the Enghoff modification of the Bohr equation. VDalveolar was calculated as: (VD / VT × VT) - anatomic dead space. Data were analyzed between groups (patients with HFpEF vs control participants) across conditions (rest, 20W, and peak exercise) using a two-way repeated measures analysis of variance and relationships were analyzed using Pearson correlation coefficient. RESULTS VDalveolar increased from rest (0.12 ± 0.07 L/breath) to 20W (0.22 ± 0.08 L/breath) in patients with HFpEF (P < .01), whereas VDalveolar did not change from rest (0.01 ± 0.06 L/breath) to 20W (0.06 ± 0.13 L/breath) in control participants (P = .19). Thereafter, VDalveolar increased from 20W to peak exercise in patients with HFpEF (0.37 ± 0.16 L/breath; P < .01 vs 20W) and control participants (0.19 ± 0.17 L/breath; P = .03 vs 20W). VDalveolar was greater in patients with HFpEF compared with control participants at rest, 20W, and peak exercise (main effect for group, P < .01). Moreover, the increase in VDalveolar correlated with the V˙E/V˙co2 slope (r = 0.69; P < .01), which was correlated with peak V˙o2peak (r = 0.46; P < .01) in patients with HFpEF. INTERPRETATION These data suggest that the increase in V˙/Q˙ mismatch may be explained by increases in VDalveolar and that increases in VDalveolar worsens ventilatory efficiency, which seems to be a key contributor to exercise intolerance in patients with HFpEF.
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Affiliation(s)
- Bryce N Balmain
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital, Dallas, TX; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX
| | - Andrew R Tomlinson
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital, Dallas, TX; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX
| | - James P MacNamara
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital, Dallas, TX; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX
| | - Linda S Hynan
- Department of Population and Data Sciences (Biostatistics) & Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX
| | - Benjamin D Levine
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital, Dallas, TX; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX
| | - Satyam Sarma
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital, Dallas, TX; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX
| | - Tony G Babb
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital, Dallas, TX; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX.
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Zhou N, Forton K, Motoji Y, Scoubeau C, Klass M, Naeije R, Faoro V. Right ventricular-pulmonary arterial coupling impairment and exercise capacity in obese adults. Front Cardiovasc Med 2022; 9:946155. [PMID: 36061564 PMCID: PMC9437327 DOI: 10.3389/fcvm.2022.946155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 08/02/2022] [Indexed: 11/13/2022] Open
Abstract
BackgroundObesity-related exercise intolerance may be associated with pulmonary vascular and right ventricular dysfunction. This study tested the hypothesis that decreased pulmonary vascular reserve and right ventricular (RV)-pulmonary arterial (PA) uncoupling contributes to exercise limitation in subjects with obesity.MethodsSeventeen subjects with obesity were matched to normo-weighted healthy controls. All subjects underwent; exercise echocardiography, lung diffusing capacity (DL) for nitric oxide (NO) and carbon monoxide (CO) and an incremental cardiopulmonary exercise test. Cardiac output (Q), PA pressure (PAP) and tricuspid annular plane systolic excursion (TAPSE) were recorded at increasing exercise intensities. Pulmonary vascular reserve was assessed by multipoint mean PAP (mPAP)/Q relationships with more reserve defined by lesser increase in mPAP at increased Q, and RV-PA coupling was assessed by the TAPSE/systolic PAP (sPAP) ratio.ResultsAt rest, subjects with obesity displayed lower TAPSE/sPAP ratios (1.00 ± 0.26 vs. 1.19 ± 0.22 ml/mmHg, P < 0.05), DLCO and pulmonary capillary blood volume (52 ± 11 vs. 64 ± 13 ml, P < 0.01) compared to controls. Exercise was associated with steeper mPAP-Q slopes, decreased TAPSE/sPAP and lower peak O2 uptake (VO2peak). The changes in TAPSE/sPAP at exercise were correlated to the body fat mass (R = 0.39, P = 0.01) and VO2peak (R = 0.44, P < 0.01).ConclusionObesity is associated with a decreased pulmonary vascular and RV-PA coupling reserve which may impair exercise capacity.
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13
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Assessment of Cardio-Respiratory Function in Overweight and Obese Children Wearing Face Masks during the COVID-19 Pandemic. CHILDREN 2022; 9:children9071053. [PMID: 35884037 PMCID: PMC9319347 DOI: 10.3390/children9071053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 07/11/2022] [Accepted: 07/11/2022] [Indexed: 11/17/2022]
Abstract
Objective: To evaluate whether the use of a surgical and N95 mask for overweight and obese children was associated with respiratory distress. Methods: We enrolled 15 healthy and 14 overweight or obese children. We performed two sessions: one wearing a surgical, the other an N95 mask. We tracked changes in partial pressure of end-tidal carbon dioxide (PETCO2), oxygen saturation (SaO2), pulse rate (PR), and respiratory rate (RR) during a 72 min test: 30 min without a mask, 30 min wearing a mask, and then during a 12 min walking test. Results: In healthy children, there was no significant change in SaO2 and PETCO2 during the study; there was a significant increase in PR and RR after the walking test with both the masks. In overweight or obese children, there was no significant change in SaO2 during the study period; there was a significant increase in PETCO2 as fast as wearing the mask and an increase in PETCO2, PR, and RR after walking test. After the walking test, we showed a significant correlation between PETCO2 and body mass index. Conclusion: Overweight or Obese children who wear a mask are more prone to developing respiratory distress, which causes them to remove it frequently. In a crowded environment, they are at greater risk of infection. For this reason, it is desirable that they attend environments where everyone uses a mask.
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Borasio N, Vecchiato M, Quinto G, Battista F, Neunhaeuserer D, Ermolao A. Correspondence regarding "Ventilatory efficiency in athletes, asthma and obesity": different ventilatory phenotypes during exercise in obesity? Eur Respir Rev 2022; 31:31/164/210253. [PMID: 35768128 DOI: 10.1183/16000617.0253-2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Accepted: 02/07/2022] [Indexed: 11/05/2022] Open
Affiliation(s)
- Nicola Borasio
- Sports and Exercise Medicine Division, Dept of Medicine, University of Padova, Padova, Italy
| | - Marco Vecchiato
- Sports and Exercise Medicine Division, Dept of Medicine, University of Padova, Padova, Italy
| | - Giulia Quinto
- Sports and Exercise Medicine Division, Dept of Medicine, University of Padova, Padova, Italy
| | - Francesca Battista
- Sports and Exercise Medicine Division, Dept of Medicine, University of Padova, Padova, Italy
| | - Daniel Neunhaeuserer
- Sports and Exercise Medicine Division, Dept of Medicine, University of Padova, Padova, Italy
| | - Andrea Ermolao
- Sports and Exercise Medicine Division, Dept of Medicine, University of Padova, Padova, Italy
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15
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Bhammar DM, Balmain BN, Babb TG, Bernhardt V. Sex differences in the ventilatory responses to exercise in mild-moderate obesity. Exp Physiol 2022; 107:965-977. [PMID: 35771362 PMCID: PMC9357174 DOI: 10.1113/ep090309] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Accepted: 06/20/2022] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the central question of the study? What are the sex differences in ventilatory responses during exercise in adults with obesity. What is the main finding and its importance? Tidal volume and expiratory flows are lower in females when compared with males at higher levels of ventilation despite small increases in end-expiratory lung volumes. Since dyspnea on exertion is a frequent complaint, particularly in females with obesity, careful attention should be paid to unpleasant respiratory symptoms and mechanical ventilatory constraints before prescribing exercise. ABSTRACT Obesity is associated with altered ventilatory responses, which may be exacerbated in females due to the functional consequences of sex-related morphological differences in the respiratory system. This study examined sex differences in ventilatory responses during exercise in adults with obesity. Healthy adults with obesity (n = 73; 48 females) underwent pulmonary function testing, underwater weighing, magnetic resonance imaging, a graded exercise test to exhaustion, and two constant work rate exercise tests; one at a fixed work rate (60W for females and 105W for males) and one at a relative intensity (50% of peak oxygen uptake, V̇O2peak ). Metabolic, respiratory, and perceptual responses were assessed during exercise. Compared with males, females used a smaller proportion of their ventilatory capacity at peak exercise (69.13 ± 14.49 vs. 77.41 ± 17.06 % maximum voluntary ventilation, P = 0.0374). Females also utilized a smaller proportion of their forced vital capacity (FVC) at peak exercise (tidal volume: 48.51±9.29 vs. 54.12±10.43 %FVC, P = 0.0218). End-expiratory lung volumes were 2-4% higher in females compared with males during exercise (P<0.05), while end-inspiratory lung volumes were similar. Since the males were initiating inspiration from a lower lung volume, they experienced greater expiratory flow limitation during exercise. Ratings of perceived breathlessness during exercise were similar between females and males at comparable levels of ventilation. In summary, sex differences in the manifestations of obestity-related mechanical ventilatory constraints were observed. Since dyspnea on exertion is a common complaint in patients with obesity, particularly in females, exercise prescriptions should be tailored with the goal of minimizing unpleasant respiratory sensations. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Dharini M Bhammar
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas and UT Southwestern Medical Center, Dallas, TX, USA.,Center for Tobacco Research, Division of Medical Oncology, Department of Internal Medicine, The Ohio State University, Columbus, OH, USA
| | - Bryce N Balmain
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas and UT Southwestern Medical Center, Dallas, TX, USA
| | - Tony G Babb
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas and UT Southwestern Medical Center, Dallas, TX, USA
| | - Vipa Bernhardt
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas and UT Southwestern Medical Center, Dallas, TX, USA.,Department of Health & Human Performance, Texas A&M University - Commerce, Commerce, TX, USA
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16
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Collins SÉ, Phillips DB, Brotto AR, Rampuri ZH, Stickland MK. Reply to: "Ventilatory efficiency in athletes, asthma and obesity": different ventilatory phenotypes during exercise in obesity? Eur Respir Rev 2022; 31:31/164/220054. [PMID: 35768131 DOI: 10.1183/16000617.0054-2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 05/19/2022] [Indexed: 11/05/2022] Open
Affiliation(s)
- Sophie É Collins
- Division of Pulmonary Medicine, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada.,Faculty of Rehabilitation Medicine, University of Alberta, Edmonton, AB, Canada
| | - Devin B Phillips
- Respiratory Investigation Unit, Dept of Medicine, Queen's University, Kingston, ON, Canada
| | - Andrew R Brotto
- Division of Pulmonary Medicine, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada.,Faculty of Kinesiology, Sport, and Recreation, University of Alberta, Edmonton, AB, Canada
| | - Zahrah H Rampuri
- Division of Pulmonary Medicine, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada
| | - Michael K Stickland
- Division of Pulmonary Medicine, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada .,G.F. MacDonald Centre for Lung Health, Covenant Health, Edmonton, AB, Canada
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D'Ascenzi F, Cavigli L, Pagliaro A, Focardi M, Valente S, Cameli M, Mandoli GE, Mueller S, Dendale P, Piepoli M, Wilhelm M, Halle M, Bonifazi M, Hansen D. Clinician approach to cardiopulmonary exercise testing for exercise prescription in patients at risk of and with cardiovascular disease. Br J Sports Med 2022; 56:bjsports-2021-105261. [PMID: 35680397 DOI: 10.1136/bjsports-2021-105261] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/29/2022] [Indexed: 12/24/2022]
Abstract
Exercise training is highly recommended in current guidelines on primary and secondary prevention of cardiovascular disease (CVD). This is based on the cardiovascular benefits of physical activity and structured exercise, ranging from improving the quality of life to reducing CVD and overall mortality. Therefore, exercise should be treated as a powerful medicine and critical component of the management plan for patients at risk for or diagnosed with CVD. A tailored approach based on the patient's personal and clinical characteristics represents a cornerstone for the benefits of exercise prescription. In this regard, the use of cardiopulmonary exercise testing is well-established for risk stratification, quantification of cardiorespiratory fitness and ventilatory thresholds for a tailored, personalised exercise prescription. The aim of this paper is to provide a practical guidance to clinicians on how to use data from cardiopulmonary exercise testing towards personalised exercise prescriptions for patients at risk of or with CVD.
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Affiliation(s)
- Flavio D'Ascenzi
- Department of Medical Biotechnologies, Division of Cardiology, University of Siena, Siena, Italy
- Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Luna Cavigli
- Department of Medical Biotechnologies, Division of Cardiology, University of Siena, Siena, Italy
| | - Antonio Pagliaro
- Department of Medical Biotechnologies, Division of Cardiology, University of Siena, Siena, Italy
| | - Marta Focardi
- Department of Medical Biotechnologies, Division of Cardiology, University of Siena, Siena, Italy
| | - Serafina Valente
- Department of Medical Biotechnologies, Division of Cardiology, University of Siena, Siena, Italy
| | - Matteo Cameli
- Department of Medical Biotechnologies, Division of Cardiology, University of Siena, Siena, Italy
| | - Giulia Elena Mandoli
- Department of Medical Biotechnologies, Division of Cardiology, University of Siena, Siena, Italy
| | - Stephan Mueller
- Department of Prevention and Sports Medicine, Technical University of Munich, Munchen, Germany
| | | | | | | | - Martin Halle
- Department of Prevention and Sports Medicine, Technical University of Munich, Munchen, Germany
- DZHK (German Center for Cardiovascular Research), Munich, Germany
| | - Marco Bonifazi
- Department of Medicine, Surgery, and NeuroScience, University of Siena, Siena, Italy
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