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Martis WR, Oughton C, Traer E, Ismail H, Riedel B. Reassessing perioperative cardiopulmonary exercise testing: point-of-care cardiac ultrasound and end-tidal pressure of carbon dioxide measurement for scalable individualised risk assessment. Br J Anaesth 2024; 133:199-202. [PMID: 38670894 DOI: 10.1016/j.bja.2024.03.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 03/06/2024] [Accepted: 03/09/2024] [Indexed: 04/28/2024] Open
Affiliation(s)
- Walston R Martis
- Department of Anaesthetics, Perioperative Medicine, and Pain Medicine, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia; Department of Anaesthetics, Monash Health, Melbourne, VIC, Australia; The Sir Peter MacCallum Department of Oncology, Department of Critical Care, University of Melbourne, Melbourne, VIC, Australia.
| | - Chad Oughton
- Department of Anaesthetics, Perioperative Medicine, and Pain Medicine, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia; Department of Anaesthetics, Perioperative Medicine, and Pain Medicine, Northern Health, Melbourne, VIC, Australia
| | - Emily Traer
- Department of Anaesthetics, Perioperative Medicine, and Pain Medicine, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia; The Sir Peter MacCallum Department of Oncology, Department of Critical Care, University of Melbourne, Melbourne, VIC, Australia
| | - Hilmy Ismail
- Department of Anaesthetics, Perioperative Medicine, and Pain Medicine, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia; The Sir Peter MacCallum Department of Oncology, Department of Critical Care, University of Melbourne, Melbourne, VIC, Australia
| | - Bernhard Riedel
- Department of Anaesthetics, Perioperative Medicine, and Pain Medicine, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia; The Sir Peter MacCallum Department of Oncology, Department of Critical Care, University of Melbourne, Melbourne, VIC, Australia
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Vecchiato M, Neunhaeuserer D, Zanardo E, Quinto G, Battista F, Aghi A, Palermi S, Babuin L, Tessari C, Guazzi M, Gasperetti A, Ermolao A. Respiratory exchange ratio overshoot during exercise recovery: a promising prognostic marker in HFrEF. Clin Res Cardiol 2024:10.1007/s00392-024-02391-9. [PMID: 38358417 DOI: 10.1007/s00392-024-02391-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Accepted: 01/31/2024] [Indexed: 02/16/2024]
Abstract
BACKGROUND AND AIMS Transient increases (overshoot) in respiratory gas analyses have been observed during exercise recovery, but their clinical significance is not clearly understood. An overshoot phenomenon of the respiratory exchange ratio (RER) is commonly observed during recovery from maximal cardiopulmonary exercise testing (CPET), but it has been found reduced in patients with heart failure with reduced ejection fraction (HFrEF). The aim of the study was to analyze the clinical significance of these RER recovery parameters and to understand if these may improve the risk stratification of patients with HFrEF. METHODS This cross-sectional study includes HFrEF patients who underwent functional evaluation with maximal CPET for the heart transplant checklist at our Sports and Exercise Medicine Division. RER recovery parameters, including RER overshoot as the percentual increase of RER during recovery (RER mag), have been evaluated after CPET with assessment of hard clinical long-term endpoints (MACEs/deaths and transplant/LVAD-free survival). RESULTS A total of 190 patients with HFrEF and 103 controls were included (54.6 ± 11.9 years; 73% male). RER recovery parameters were significantly lower in patients with HFrEF compared to healthy subjects (RER mag 24.8 ± 14.5% vs 31.4 ± 13.0%), and they showed significant correlations with prognostically relevant CPET parameters. Thirty-three patients with HFrEF did not present a RER overshoot, showing worse cardiorespiratory fitness and efficiency when compared with those patients who showed a detectable overshoot (VO2 peak: 11.0 ± 3.1 vs 15.9 ± 5.1 ml/kg/min; VE/VCO2 slope: 41.5 ± 8.7 vs 32.9 ± 7.9; ΔPETCO2: 2.75 ± 1.83 vs 4.45 ± 2.69 mmHg, respectively). The presence of RER overshoot was associated with a lower risk of cardiovascular events and longer transplant-free survival. CONCLUSION RER overshoot represents a meaningful cardiorespiratory index to monitor during exercise gas exchange evaluation; it is an easily detectable parameter that could support clinicians to comprehensively interpreting patients' functional impairment and prognosis. CPET recovery analyses should be implemented in the clinical decision-making of advanced HF.
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Affiliation(s)
- Marco Vecchiato
- Sports and Exercise Medicine Division, Department of Medicine, University of Padova, University Hospital of Padova, Via Giustiniani 2, 35128, Padova, Italy
| | - Daniel Neunhaeuserer
- Sports and Exercise Medicine Division, Department of Medicine, University of Padova, University Hospital of Padova, Via Giustiniani 2, 35128, Padova, Italy.
| | - Emanuele Zanardo
- Sports and Exercise Medicine Division, Department of Medicine, University of Padova, University Hospital of Padova, Via Giustiniani 2, 35128, Padova, Italy
| | - Giulia Quinto
- Sports and Exercise Medicine Division, Department of Medicine, University of Padova, University Hospital of Padova, Via Giustiniani 2, 35128, Padova, Italy
| | - Francesca Battista
- Sports and Exercise Medicine Division, Department of Medicine, University of Padova, University Hospital of Padova, Via Giustiniani 2, 35128, Padova, Italy
| | - Andrea Aghi
- Fisioterapia Osteopatia Raimondi Di Giovanni e Daniele, Piazza Vittorio Veneto 1, Selvazzano Dentro, Padova, Italy
| | - Stefano Palermi
- Public Health Department, University of Naples Federico II, 80131, Naples, Italy
| | - Luciano Babuin
- Cardiology Unit, Department of Cardiac, Thoracic, Vascular Sciences and Public Health, University Hospital of Padova, Padova, Italy
| | - Chiara Tessari
- Cardiac Surgery Unit, Department of Cardiac, Thoracic, Vascular Sciences and Public Health, University Hospital of Padova, Padova, Italy
| | - Marco Guazzi
- Department of Biological Sciences, University of Milano School of Medicine, Milan, Italy
- Cardiology Division, San Paolo Hospital, Milan, Italy
| | - Andrea Gasperetti
- Sports and Exercise Medicine Division, Department of Medicine, University of Padova, University Hospital of Padova, Via Giustiniani 2, 35128, Padova, Italy
| | - Andrea Ermolao
- Sports and Exercise Medicine Division, Department of Medicine, University of Padova, University Hospital of Padova, Via Giustiniani 2, 35128, Padova, Italy
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Vianna MVA, Ávila MR, Figueiredo PHS, Lima VP, Carvalho LMS, da Cruz Ferreira PH, de Oliveira LFF, Silva WT, de Almeida ILGI, Lacerda ACR, Mendonça VA, de Castro Faria SC, Mediano MFF, da Costa Rocha MO, Costa HS. Functional predictors of poor outcomes in Chagas cardiomyopathy: The value of end-tidal carbon dioxide at peak exercise. Heart Lung 2023; 62:152-156. [PMID: 37531867 DOI: 10.1016/j.hrtlng.2023.07.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 07/07/2023] [Accepted: 07/28/2023] [Indexed: 08/04/2023]
Abstract
BACKGROUND Functional impairment can be detected from the onset of heart disease in patients with Chagas cardiomyopathy (ChC) and the prognostic value of the end-tidal carbon dioxide at peak exercise (PETCO2 peak) should be investigated. OBJECTIVE To verify the prognostic value of PETCO2 peak in patients with ChC. METHODS Seventy-six patients with ChC (49.2 ± 9.8 years, NYHA I-III) were evaluated by echocardiography and Cardiopulmonary Exercise Testing. Patients were followed up to four years and the end-point was defined as cardiovascular death, stroke, or cardiac transplantation. RESULTS At the end of the follow-up period (29.0 ± 16.0 months), 16 patients (21%) had experienced adverse events. The area under the receiver operating characteristic (ROC) curve to identify the risk of adverse events by PETCO2 peak in patients with ChC was 0.83 (95% CI: 0.69 to 0.97), and the value of 32 mmHg was the optimal cut point (70% of sensitivity and 85% of specificity). In the Kaplan-Meier diagram, there was a significant difference (p<0.001) between patients with reduced (≤ 32 mmHg) and preserved PETCO2 peak (>32 mmHg). In the final Cox multivariate model, only reduced PETCO2 peak (HR 4.435; 95% CI: 1.228 to 16.016, p = 0.023) and VO2peak (HR 0.869; 95% CI: 0.778 to 0.971, p = 0.013) remained as independent predictors of poor outcome in ChC patients. CONCLUSION Reduced PETCO2 peak and VO2peak demonstrated valuable prognostic value in patients with ChC. The cutoff points for both functional variables can be used during risk stratification and may help in the development of therapeutic strategies in ChC patients.
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Affiliation(s)
- Marcus Vinícius Accetta Vianna
- Postgraduate Course of Reabilitação e Desempenho Funcional, Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM), Diamantina, Brazil; Medical School, Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM), Diamantina, Brazil
| | - Matheus Ribeiro Ávila
- Postgraduate Course of Reabilitação e Desempenho Funcional, Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM), Diamantina, Brazil
| | - Pedro Henrique Scheidt Figueiredo
- Postgraduate Course of Reabilitação e Desempenho Funcional, Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM), Diamantina, Brazil
| | - Vanessa Pereira Lima
- Postgraduate Course of Reabilitação e Desempenho Funcional, Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM), Diamantina, Brazil
| | - Liliany Mara Silva Carvalho
- Postgraduate Course of Health Sciences, Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM), Diamantina, Brazil
| | - Paulo Henrique da Cruz Ferreira
- Postgraduate Course of Health Sciences, Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM), Diamantina, Brazil
| | - Lucas Fróis Fernandes de Oliveira
- Postgraduate Course of Reabilitação e Desempenho Funcional, Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM), Diamantina, Brazil
| | - Whesley Tanor Silva
- Postgraduate Course of Reabilitação e Desempenho Funcional, Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM), Diamantina, Brazil
| | | | - Ana Cristina Rodrigues Lacerda
- Postgraduate Course of Reabilitação e Desempenho Funcional, Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM), Diamantina, Brazil
| | - Vanessa Amaral Mendonça
- Postgraduate Course of Reabilitação e Desempenho Funcional, Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM), Diamantina, Brazil
| | - Sanny Cristina de Castro Faria
- Department of Internal Medicine, Medical School and Hospital das Clinicas of the Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, Brazil
| | | | - Manoel Otávio da Costa Rocha
- Department of Internal Medicine, Medical School and Hospital das Clinicas of the Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, Brazil
| | - Henrique Silveira Costa
- Postgraduate Course of Reabilitação e Desempenho Funcional, Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM), Diamantina, Brazil; Postgraduate Course of Health Sciences, Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM), Diamantina, Brazil.
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Pretreatment of Nicorandil Protects the Heart from Exhaustive Exercise-Induced Myocardial Injury in Rats. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2022; 2022:7550872. [PMID: 35035509 PMCID: PMC8758261 DOI: 10.1155/2022/7550872] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 11/02/2021] [Accepted: 11/12/2021] [Indexed: 11/17/2022]
Abstract
OBJECTIVE Nicorandil has been widely used for the treatment of angina pectoris and myocardial infarction. The purpose of this study was to investigate whether nicorandil plays a protective role in exhaustive exercise (EE)-induced myocardial injury. METHODS Here, we applied the rat EE model and treated them with exercise preconditioning (EP, reported to protect the heart) or different doses of nicorandil gavage, respectively, to explore whether there are protective effects of single EP or nicorandil or a combination of both and the potential mechanism. Forty-nine male Sprague Dawley rats were randomly divided into control, EE, EP + EE, nicorandil (with low, middle, and high dose) + EE, and EP + nicorandil (middle dose) + EE. Blood samples and myocardial tissues were collected to analyze the myocardial injury-related index. RESULTS EE induced myocardial structural damage and altered the myocardial injury markers, which were partially reversed by pretreatment of nicorandil. In addition, oxidative stress and inflammation lead to the accumulation of reactive oxygen species (ROS) products and further damage to the myocardium, while pretreatment of nicorandil reduces the oxidative stress response and inflammation. Moreover, nicorandil suppressed the myocardial apoptosis induced by EE, as indicated by a decrease of Bax and caspase-3 expression and an increase of Bcl-2 expression. Finally, the pathway in which nicorandil plays a role may be involved in the endothelial nitric oxide synthase (eNOS)/nitric oxide (NO) pathway. Pretreatment of nicorandil increased the protein level of myocardial eNOS and NO production. CONCLUSION Our result demonstrated that nicorandil has protective effects in EE-induced myocardial injury with dose-dependent effects. A combination of nicorandil and EP can further improve the protective effects. Taken together, nicorandil can be potentially used as an intervention method in EE-induced myocardial injury.
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H 2O 2 Signaling-Triggered PI3K Mediates Mitochondrial Protection to Participate in Early Cardioprotection by Exercise Preconditioning. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2018; 2018:1916841. [PMID: 30147831 PMCID: PMC6083504 DOI: 10.1155/2018/1916841] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 05/05/2018] [Accepted: 06/19/2018] [Indexed: 12/15/2022]
Abstract
Previous studies have shown that early exercise preconditioning (EEP) imparts a protective effect on acute cardiovascular stress. However, how mitophagy participates in exercise preconditioning- (EP-) induced cardioprotection remains unclear. EEP may involve mitochondrial protection, which presumably crosstalks with predominant H2O2 oxidative stress. Our EEP protocol involves four periods of 10 min running with 10 min recovery intervals. We added a period of exhaustive running and a pretreatment using phosphoinositide 3-kinase (PI3K)/autophagy inhibitor wortmannin to test this protective effect. By using transmission electron microscopy (TEM), laser scanning confocal microscopy, and other molecular biotechnology methods, we detected related markers and specifically analyzed the relationship between mitophagic proteins and mitochondrial translocation. We determined that exhaustive exercise associated with various elevated injuries targeted the myocardium, oxidative stress, hypoxia-ischemia, and mitochondrial ultrastructure. However, exhaustion induced limited mitochondrial protection through a H2O2-independent manner to inhibit voltage-dependent anion channel isoform 1 (VDAC1) instead of mitophagy. EEP was apparently safe to the heart. In EEP-induced cardioprotection, EEP provided suppression to exhaustive exercise (EE) injuries by translocating Bnip3 to the mitochondria by recruiting the autophagosome protein LC3 to induce mitophagy, which is potentially triggered by H2O2 and influenced by Beclin1-dependent autophagy. Pretreatment with the wortmannin further attenuated these effects induced by EEP and resulted in the expression of proapoptotic phenotypes such as oxidative injury, elevated Beclin1/Bcl-2 ratio, cytochrome c leakage, mitochondrial dynamin-1-like protein (Drp-1) expression, and VDAC1 dephosphorylation. These observations suggest that H2O2 generation regulates mitochondrial protection in EEP-induced cardioprotection.
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Yuan Y, Pan SS, Shen YJ. Cardioprotection of exercise preconditioning involving heat shock protein 70 and concurrent autophagy: a potential chaperone-assisted selective macroautophagy effect. J Physiol Sci 2018; 68:55-67. [PMID: 27928720 PMCID: PMC10717675 DOI: 10.1007/s12576-016-0507-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Accepted: 11/21/2016] [Indexed: 12/23/2022]
Abstract
It has been confirmed that exercise preconditioning (EP) has a protective effect on acute cardiovascular stress. However, how Hsp70 participates in EP-induced cardioprotection is unknown. EP may involve Hsp70 to repair unfolded proteins or may also stabilize the function of the endoplasmic reticulum via Hsp70-related autophagy to work on a protective formation. Our EP protocol involves four periods of 10 min running with 10 min recovery intervals. We added a period of exhaustive running to test this protective effect, using histology and molecular biotechnology methods to detect related markers. EP provided cardioprotection at its early and late phases against exhaustive exercise-induced ischemic myocardial injury. Results showed that Hsp70 co-chaperone protein BAG3, ubiquitin adaptor p62 and critical autophagy protein LC3 were significantly upregulated at the early phase. Meanwhile, Hsp70, Hsp70/BAG3 co-localization extent, LC31 and LC3II were significantly upregulated at the late phase. Hsp70 mRNA levels and LC3II/I ratios were also consistent with the extent of myocardial injury following exhaustive exercise. Hsp70 increase was delayed relative to BAG3 and p62 after EP, indicating a pre-synthesized phenomenon of BAG3 and p62 for chaperone-assisted selective autophagy (CASA). The decreased Hsp70, BAG3 and p62 levels and increased Hsp70/BAG3 co-localization extent and LC3 levels induced by exhaustive exercise after EP suggest that EP-induced cardioprotection might associate with CASA. Hsp70 has a cardioprotective role and has a closer link with CASA in LEP. Additionally, EP may not cause exhaustion-dependent excessive autophagy regulation. Collectively, during early and late EP, CASA potentially plays different roles in cardioprotection.
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Affiliation(s)
- Yang Yuan
- School of Kinesiology, Shanghai University of Sport, 399 Changhai Road, Shanghai, 200438, China
| | - Shan-Shan Pan
- School of Kinesiology, Shanghai University of Sport, 399 Changhai Road, Shanghai, 200438, China.
| | - Yu-Jun Shen
- School of Kinesiology, Shanghai University of Sport, 399 Changhai Road, Shanghai, 200438, China
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Ramos RP, Alencar MCN, Treptow E, Arbex F, Ferreira EMV, Neder JA. Clinical usefulness of response profiles to rapidly incremental cardiopulmonary exercise testing. Pulm Med 2013; 2013:359021. [PMID: 23766901 PMCID: PMC3666297 DOI: 10.1155/2013/359021] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2012] [Revised: 12/17/2012] [Accepted: 01/15/2013] [Indexed: 02/06/2023] Open
Abstract
The advent of microprocessed "metabolic carts" and rapidly incremental protocols greatly expanded the clinical applications of cardiopulmonary exercise testing (CPET). The response normalcy to CPET is more commonly appreciated at discrete time points, for example, at the estimated lactate threshold and at peak exercise. Analysis of the response profiles of cardiopulmonary responses at submaximal exercise and recovery, however, might show abnormal physiologic functioning which would not be otherwise unraveled. Although this approach has long been advocated as a key element of the investigational strategy, it remains largely neglected in practice. The purpose of this paper, therefore, is to highlight the usefulness of selected submaximal metabolic, ventilatory, and cardiovascular variables in different clinical scenarios and patient populations. Special care is taken to physiologically justify their use to answer pertinent clinical questions and to the technical aspects that should be observed to improve responses' reproducibility and reliability. The most recent evidence in favor of (and against) these variables for diagnosis, impairment evaluation, and prognosis in systemic diseases is also critically discussed.
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Affiliation(s)
- Roberta P. Ramos
- Pulmonary Function and Clinical Exercise Physiology Unit (SEFICE), Division of Respiratory Diseases, Department of Medicine, Federal University of Sao Paulo (UNIFESP), Rua Francisco de Castro 54, Vila Mariana, 04020-050 São Paulo, SP, Brazil
| | - Maria Clara N. Alencar
- Pulmonary Function and Clinical Exercise Physiology Unit (SEFICE), Division of Respiratory Diseases, Department of Medicine, Federal University of Sao Paulo (UNIFESP), Rua Francisco de Castro 54, Vila Mariana, 04020-050 São Paulo, SP, Brazil
| | - Erika Treptow
- Pulmonary Function and Clinical Exercise Physiology Unit (SEFICE), Division of Respiratory Diseases, Department of Medicine, Federal University of Sao Paulo (UNIFESP), Rua Francisco de Castro 54, Vila Mariana, 04020-050 São Paulo, SP, Brazil
| | - Flávio Arbex
- Pulmonary Function and Clinical Exercise Physiology Unit (SEFICE), Division of Respiratory Diseases, Department of Medicine, Federal University of Sao Paulo (UNIFESP), Rua Francisco de Castro 54, Vila Mariana, 04020-050 São Paulo, SP, Brazil
| | - Eloara M. V. Ferreira
- Pulmonary Function and Clinical Exercise Physiology Unit (SEFICE), Division of Respiratory Diseases, Department of Medicine, Federal University of Sao Paulo (UNIFESP), Rua Francisco de Castro 54, Vila Mariana, 04020-050 São Paulo, SP, Brazil
| | - J. Alberto Neder
- Pulmonary Function and Clinical Exercise Physiology Unit (SEFICE), Division of Respiratory Diseases, Department of Medicine, Federal University of Sao Paulo (UNIFESP), Rua Francisco de Castro 54, Vila Mariana, 04020-050 São Paulo, SP, Brazil
- Division of Respiratory and Critical Care Medicine, Department of Medicine, Queen's University and Kingston General Hospital, Richardson House, 102 Stuart Street, Kingston, ON, Canada K7L 2V6
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Kano H, Koike A, Hoshimoto-Iwamoto M, Nagayama O, Sakurada K, Suzuki T, Tsuneoka H, Sawada H, Aizawa T, Wasserman K. Abnormal end-tidal PO(2) and PCO(2) at the anaerobic threshold correlate well with impaired exercise gas exchange in patients with left ventricular dysfunction. Circ J 2011; 76:79-87. [PMID: 22094908 DOI: 10.1253/circj.cj-11-0599] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND The aim of the present study was to compare the end-tidal O(2) pressure (PETO(2)) to end-tidal CO(2) pressure (PETCO(2)) in cardiac patients during rest and during 2 states of exercise: at anaerobic threshold (AT) and at peak. The purpose was to see which metabolic state, PETO(2) or PETCO(2), best correlated with exercise limitation. METHODS AND RESULTS Thirty-eight patients with left ventricular (LV) ejection fraction <40% underwent cardiopulmonary exercise testing (CPX). PETO(2) and PETCO(2) were measured during CPX, along with peak O(2) uptake (VO(2)), AT, slope of the increase in ventilation (VE) relative to the increase in CO(2) output (VCO(2)) (VE vs. VCO(2) slope), and the ratio of the increase in VO(2) to the increase in work rate (ΔVO(2)/ΔWR). Both PETO(2) and PETCO(2) measured at AT were best correlated with peakVO(2), AT, ΔVO(2)/ΔWR and VE vs. VCO(2) slope. PETO(2) at AT correlated with reduced peak VO(2) (r=-0.60), reduced AT (r=-0.52), reduced ΔVO(2)/ΔWR (r=-0.55) and increased VE vs. VCO(2) slope (r=0.74). PETCO(2) at AT correlated with reduced peak VO(2) (r=0.67), reduced AT (r=0.61), reduced ΔVO(2)/ΔWR (r=0.58) and increased VE vs. VCO(2) slope (r=-0.80). CONCLUSIONS PETCO(2) and PETO(2) at AT correlated with peak VO(2), AT and ΔVO(2)/ΔWR, but best correlated with increased VE vs. VCO(2) slope. PETO(2) and PETCO(2) at AT can be used as a prime index of impaired cardiopulmonary function during exercise in patients with LV failure.
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Sue DY. Excess ventilation during exercise and prognosis in chronic heart failure. Am J Respir Crit Care Med 2011; 183:1302-10. [PMID: 21257789 DOI: 10.1164/rccm.201006-0965ci] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Excess ventilation during exercise with accompanying dyspnea is characteristic of chronic heart failure (CHF), and these patients often exhibit increased Ve relative to the Vco(2) compared with normal subjects. This can be measured in several ways, including using such variables as the slope of Ve versus Vco(2), the lowest ratio of Ve/Vco(2), and the ratio of Ve/Vco(2) at the lactic acidosis threshold or peak exercise. There is now considerable evidence that the degree of excess ventilation during exercise in patients with CHF is a robust predictor of outcome and identifies higher-risk patients requiring aggressive treatment, including heart transplantation. The mechanism of excess ventilation in patients with CHF during exercise is not completely understood. It may be related to enhanced output of chemoreceptors or peripheral muscle ergoreceptors, increased dead space/Vt ratio due to increased contribution of high ventilation-perfusion lung regions or rapid shallow breathing caused by earlier onset of lactic acidosis, or likely resulting from a combination of these causes.
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Affiliation(s)
- Darryl Y Sue
- Department of Medicine, Harbor-UCLA Medical Center, Torrance, CA 90509-2910, USA.
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