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Gillet A, Grolaux T, Forton K, Ibrahim M, Lamotte M, Roussoulieres A, Dewachter C, Faoro V, Chaumont M, Deboeck G, van de Borne P. Effect of a new resistance training method on the metaboreflex in cardiac rehabilitation patients: a randomized controlled trial. Eur J Appl Physiol 2024:10.1007/s00421-024-05570-8. [PMID: 39102020 DOI: 10.1007/s00421-024-05570-8] [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: 05/26/2024] [Accepted: 07/26/2024] [Indexed: 08/06/2024]
Abstract
Patients with cardiac disease exhibit exaggerated sympathoexcitation, pressor, and ventilatory responses to muscle metaboreflex activation (MMA). However, the effects of cardiac rehabilitation (CR) and especially resistance training (RT) modalities on MMA are not well known. This study investigated how CR impacts MMA in such patients, specifically examining the effects of two different resistance training (RT) protocols following 12 weeks of CR. In addition to endurance exercises, 32 patients were randomized into either a 3/7 RT modality (comprising 5 sets of 3-7 repetitions) or a control (CTRL) modality (involving 3 sets of 9 repetitions), with distinct inter-set rest intervals (15 s for 3/7 and 60 s for CTRL). MMA, gauged by blood pressure (BP) and ventilatory (Ve) responses during a handgrip exercise at 40% effort and subsequent post-exercise circulatory occlusion, demonstrated CR's significant impact. Systolic BP, initially at + 28 ± 23% pre-CR, improved to + 11 ± 15% post-CR (P = .011 time effect; P = .131 group effect). Diastolic BP showed a similar trend, from + 27 ± 23% to + 13 ± 15% (P = .099 time effect; P = .087 group effect). Ve, initially at + 60 ± 39%, reduced to + 14 ± 19% post-CR (P < .001 time effect; P = .142 group effect). Critical parameters-maximal oxygen consumption, lean mass, hand grip, and quadriceps strength-exhibited parallel increases in both 3/7 and CTRL groups (P < .05 time effect; P > .3 group effect). Ultimately, CR demonstrated comparable improvements in MMA across both RT modalities, indicating its positive influence on cardiovascular responses and physical performance in individuals with cardiac conditions.
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Affiliation(s)
- Alexis Gillet
- Department of Cardiology, Université Libre de Bruxelles (ULB), Hôpital Universitaire de Bruxelles (H.U.B), CUB Hôpital Erasme, route de Lennik 808,1070, Brussels, Belgium.
- Department of Physiotherapy, Université Libre de Bruxelles (ULB), Hôpital Universitaire de Bruxelles (H.U.B), CUB Hôpital Erasme, Brussels, Belgium.
- Research Unit in Rehabilitation, Faculty of Human Movement Sciences, Université Libre de Bruxelles (ULB), Brussels, Belgium.
| | - Thomas Grolaux
- Department of Cardiology, Université Libre de Bruxelles (ULB), Hôpital Universitaire de Bruxelles (H.U.B), CUB Hôpital Erasme, route de Lennik 808,1070, Brussels, Belgium
| | - Kevin Forton
- Department of Cardiology, Université Libre de Bruxelles (ULB), Hôpital Universitaire de Bruxelles (H.U.B), CUB Hôpital Erasme, route de Lennik 808,1070, Brussels, Belgium
- Department of Physiotherapy, Université Libre de Bruxelles (ULB), Hôpital Universitaire de Bruxelles (H.U.B), CUB Hôpital Erasme, Brussels, Belgium
| | - Malko Ibrahim
- Research Unit in Rehabilitation, Faculty of Human Movement Sciences, Université Libre de Bruxelles (ULB), Brussels, Belgium
| | - Michel Lamotte
- Department of Cardiology, Université Libre de Bruxelles (ULB), Hôpital Universitaire de Bruxelles (H.U.B), CUB Hôpital Erasme, route de Lennik 808,1070, Brussels, Belgium
- Department of Physiotherapy, Université Libre de Bruxelles (ULB), Hôpital Universitaire de Bruxelles (H.U.B), CUB Hôpital Erasme, Brussels, Belgium
| | - Ana Roussoulieres
- Department of Cardiology, Université Libre de Bruxelles (ULB), Hôpital Universitaire de Bruxelles (H.U.B), CUB Hôpital Erasme, route de Lennik 808,1070, Brussels, Belgium
| | - Céline Dewachter
- Department of Cardiology, Université Libre de Bruxelles (ULB), Hôpital Universitaire de Bruxelles (H.U.B), CUB Hôpital Erasme, route de Lennik 808,1070, Brussels, Belgium
- Laboratory of Physiology and Pharmacology, Faculty of Medicine, Université Libre de Bruxelles (ULB), Brussels, Belgium
| | - Vitalie Faoro
- Laboratory of Physiology, Faculty of Human Movement Sciences, Université Libre de Bruxelles (ULB), Brussels, Belgium
| | - Martin Chaumont
- Department of Cardiology, Université Libre de Bruxelles (ULB), Hôpital Universitaire de Bruxelles (H.U.B), CUB Hôpital Erasme, route de Lennik 808,1070, Brussels, Belgium
| | - Gaël Deboeck
- Research Unit in Rehabilitation, Faculty of Human Movement Sciences, Université Libre de Bruxelles (ULB), Brussels, Belgium
| | - Philippe van de Borne
- Department of Cardiology, Université Libre de Bruxelles (ULB), Hôpital Universitaire de Bruxelles (H.U.B), CUB Hôpital Erasme, route de Lennik 808,1070, Brussels, Belgium
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Coats AJS. Sodium-glucose cotransporter 2 inhibitors and skeletal muscle. Eur J Heart Fail 2024; 26:936-937. [PMID: 38562026 DOI: 10.1002/ejhf.3219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Accepted: 03/14/2024] [Indexed: 04/04/2024] Open
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Kjellström B, Ivarsson B, Landenfelt Gestré LL, Ryftenius H, Nisell M. Respiratory rate modulation improves symptoms in patients with pulmonary hypertension. SAGE Open Med 2021; 9:20503121211053930. [PMID: 34733511 PMCID: PMC8558785 DOI: 10.1177/20503121211053930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Accepted: 09/30/2021] [Indexed: 11/17/2022] Open
Abstract
Background: Pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension are chronic diseases with a severe symptom burden. Common symptoms are dyspnoea at light activity and general fatigue that limits daily activities. Respiratory modulation by device-guided breathing decreased symptoms in patients with heart failure. The aim of this pilot study was to investigate if respiratory modulation could improve symptoms of dyspnoea in patients with pulmonary arterial hypertension or chronic thromboembolic pulmonary hypertension. Method: Adult patients with pulmonary arterial hypertension or chronic thromboembolic pulmonary hypertension with symptoms of dyspnoea at rest or light activity performed home-based respiratory modulation by device-guided breathing 20 min a day for 3 months. Patients were on stable disease-specific treatment ⩾3 months and willing to undergo all study procedures. Dyspnoea score, World Health Organization class, physical status, N-terminal pro b-type natriuretic peptide, quality of life, respiratory rate and 6-min walk distance were assessed before and after 3 months with respiratory modulation. Results: Nine patients with pulmonary arterial hypertension and five with chronic thromboembolic pulmonary hypertension completed the study protocol. Mean age was 71 ± 14 years, and 11 were women. After 3 months of respiratory modulation, dyspnoea score (−0.6, p = 0.014), respiratory rate at rest (−3 breaths/min, p = 0.013), World Health Organization class (−0.3, p = 0.040), quality of life (EuroQol Visual Analogue Scale +5 points, not significant) and decreased N-terminal pro b-type natriuretic peptide (−163 ng/L, p = 0.043) had improved. The fatigue and respiratory rate after the 6-min walk decreased while the 6-min walk distance remained unchanged. Conclusion: Patients with pulmonary arterial hypertension or chronic thromboembolic pulmonary hypertension that used device-guided breathing for 3 months improved symptoms of dyspnoea and lowered the respiratory rate at rest and after exercise.
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Affiliation(s)
- Barbro Kjellström
- Department of Clinical Sciences, Lund University and Clinical Physiology, Skåne University Hospital, Lund, Sweden.,Cardiology Unit, Department of Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Bodil Ivarsson
- Department of Clinical Sciences, Lund University, Cardiothoracic Surgery and Medicine Services University Trust, Region Skåne, Lund, Sweden
| | | | - Henrik Ryftenius
- Lung Unit, Karolinska University Hospital and Department of Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Magnus Nisell
- Lung Unit, Karolinska University Hospital and Department of Medicine, Karolinska Institutet, Stockholm, Sweden
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Abstract
PURPOSE OF REVIEW Heart failure is a frequent problem in an ageing population, associated with high rates of morbidity and mortality. Today, it is important to not only treat heart failure itself but also the related comorbidities. Among them, cardiac cachexia is one of the major challenges. It is a complex multifactorial disease with a negative impact on quality of life and prognosis. Therefore, prevention, early recognition and treatment of cardiac cachexia is essential. RECENT FINDINGS Cardiac cachexia frequently presents with skeletal as well as heart muscle depletion. Imaging-based diagnostic techniques can help to identify patients with cardiac cachexia and muscle wasting. Several blood biomarkers are available to detect metabolic changes in cardiac cachexia. SUMMARY Several studies are currently ongoing to better comprehend the underlying pathophysiological mechanisms of cardiac cachexia and to find new treatments. It is essential to diagnose it as early as possible to initiate therapy.
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Melenovsky V, Hlavata K, Sedivy P, Dezortova M, Borlaug BA, Petrak J, Kautzner J, Hajek M. Skeletal Muscle Abnormalities and Iron Deficiency in Chronic Heart Failure An Exercise 31P Magnetic Resonance Spectroscopy Study of Calf Muscle. Circ Heart Fail 2019; 11:e004800. [PMID: 30354361 DOI: 10.1161/circheartfailure.117.004800] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
BACKGROUND Heart failure (HF) is often associated with iron deficiency (ID). Skeletal muscle abnormalities are common in HF, but the potential role of ID in this phenomenon is unclear. In addition to hemopoiesis, iron is essential for muscle bioenergetics. We examined whether energetic abnormalities in skeletal muscle in HF are affected by ID and if they are responsive to intravenous iron. METHODS AND RESULTS Forty-four chronic HF subjects and 25 similar healthy volunteers underwent 31P magnetic resonance spectroscopy of calf muscle at rest and during exercise (plantar flexions). Results were compared between HF subjects with or without ID. In 13 ID-HF subjects, examinations were repeated 1 month after intravenous ferric carboxymaltose administration (1000 mg). As compared with controls, HF subjects displayed lower resting high-energy phosphate content, lower exercise pH, and slower postexercise PCr recovery. Compared with non-ID HF, ID-HF subjects had lower muscle strength, larger PCr depletion, and more profound intracellular acidosis with exercise, consistent with an earlier metabolic shift to anaerobic glycolysis. The exercise-induced PCr drop strongly correlated with pH change in HF group ( r=-0.71, P<0.001) but not in controls ( r=0.13, P=0.61, interaction: P<0.0001). Short-term iron administration corrected the iron deficit but had no effect on muscle bioenergetics assessed 1 month later. CONCLUSIONS HF patients display skeletal muscle myopathy that is more severe in those with iron deficiency. The presence of ID is associated with greater acidosis with exercise, which may explain early muscle fatigue. Further study is warranted to identify the strategy to restore iron content in skeletal muscle.
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Affiliation(s)
- Vojtech Melenovsky
- Department of Cardiology, Institute for Clinical and Experimental Medicine, IKEM, Prague, Czech Republic (V.M., K.H., J.K.)
| | - Katerina Hlavata
- Department of Cardiology, Institute for Clinical and Experimental Medicine, IKEM, Prague, Czech Republic (V.M., K.H., J.K.)
| | - Petr Sedivy
- Diagnostic and Interventional Radiology, Institute for Clinical and Experimental Medicine, IKEM, Prague, Czech Republic (P.S., M.D., M.H.)
| | - Monika Dezortova
- Diagnostic and Interventional Radiology, Institute for Clinical and Experimental Medicine, IKEM, Prague, Czech Republic (P.S., M.D., M.H.)
| | - Barry A Borlaug
- Department of Cardiovascular Disease, Mayo Clinic, Rochester, MN (B.A.B.)
| | - Jiri Petrak
- Department of Cardiology, Institute for Clinical and Experimental Medicine, IKEM, Prague, Czech Republic (V.M., K.H., J.K.)
| | - Josef Kautzner
- BIOCEV, First Faculty of Medicine, Charles University, Vestec, Czech Republic (J.P.)
| | - Milan Hajek
- Diagnostic and Interventional Radiology, Institute for Clinical and Experimental Medicine, IKEM, Prague, Czech Republic (P.S., M.D., M.H.)
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Maslarska M, Weis C, Bode C, Hehrlein C. Shear Wave Elastography of Peripheral Muscle Weakness in Patients with Chronic Congestive Heart Failure. ULTRASOUND IN MEDICINE & BIOLOGY 2018; 44:2531-2539. [PMID: 30286950 DOI: 10.1016/j.ultrasmedbio.2018.08.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2018] [Revised: 08/16/2018] [Accepted: 08/17/2018] [Indexed: 06/08/2023]
Abstract
Forty-five study participants (28 chronic heart failure [CHF] patients and 17 control participants) were prospectively enrolled in this study to investigate the clinical potential of ultrasound shear wave elastography (SWE) in identifying peripheral muscle weaknesses in chronic heart failure patients. Muscle stiffness in the gastrocnemius muscle during extension (stretch) and the lower arm flexor muscles during flexion was assessed via shear wave elastography, measuring the shear modulus (kPa) for the resting and contractile states in a range of 0-300 kPa. Resting kPa revealed no significant difference between CHF and CP, but exercise kPa for extension and flexion was significantly lower in CHF than CP. The area under the receiver operating characteristic curve of the denominator kPa-Exercise stretch was 0.916, associated with a sensitivity of 89%, a specificity of 71% and a corresponding cutoff value of 81.1 kPa. Shear wave elastography is thus a reproducible and sensitive ultrasound method for evaluating peripheral muscle deficits in patients with CHF.
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Affiliation(s)
- Mariya Maslarska
- Department of Cardiology I, University Heart Center Freiburg, Freiburg, Germany
| | - Christoph Weis
- Department of Cardiology I, University Heart Center Freiburg, Freiburg, Germany
| | - Christoph Bode
- Department of Cardiology I, University Heart Center Freiburg, Freiburg, Germany
| | - Christoph Hehrlein
- Department of Cardiology I, University Heart Center Freiburg, Freiburg, Germany.
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7
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High-intensity aerobic interval training can lead to improvement in skeletal muscle power among in-hospital patients with advanced heart failure. Heart Vessels 2018; 33:752-759. [DOI: 10.1007/s00380-018-1120-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 01/05/2018] [Indexed: 12/25/2022]
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8
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Ding R. Exercise-Based Rehabilitation for Heart Failure: Clinical Evidence. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 1000:31-49. [PMID: 29098614 DOI: 10.1007/978-981-10-4304-8_3] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
People with heart failure experience marked reduction in their exercise capacity which has detrimental effects on their activities of daily living, health-related quality of life, and ultimately their hospital ad-mission rate and mortality. Numerous cardiac rehabilitation studies have demonstrated functional benefits, improvement in quality of life and clinical outcomes from exercise training in patients with HFrEF. Based on evidences, the American College of Cardiology/American Heart Association, European Society of Cardiology, and National Institute for Health and Care Excellence(NICE) consistently recommend exercise-based cardiac rehabilitation(CR) as an effective and safe adjunct for patients with stable class II to III heart failure (HF) who do not have advanced arrhythmias and who do not have other limitations to exercise. This recommendation applies to patients with HFrEF as well as to patients with HFpEF besides patients with class IV HF, although the data are not as robust for patients with HFpEF. In this article, the clinical evidence on effects of exercise for HFrEF and HFpEF as well as end-stage heart failure were separately reviewed.
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Affiliation(s)
- Rongjing Ding
- Department of Cardiology, Peking University People's Hospital, Beijing, 100044, People's Republic of China.
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9
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Truong AD, Kho ME, Brower RG, Feldman DR, Colantuoni E, Needham DM. Effects of neuromuscular electrical stimulation on cytokines in peripheral blood for healthy participants: a prospective, single-blinded Study. Clin Physiol Funct Imaging 2015; 37:255-262. [PMID: 26475418 DOI: 10.1111/cpf.12290] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Accepted: 06/29/2015] [Indexed: 12/30/2022]
Abstract
INTRODUCTION The effect of exercise on cytokines may improve muscle strength. Neuromuscular electrical stimulation (NMES) is a muscle-preserving therapy that benefits patients unable to participate in active exercise. How NMES alters cytokines is unclear. The aim of this study was to study the effects of 1 NMES session on cytokines associated with protein metabolism during exercise. METHODS We evaluated the effects of NMES on IL-1, IL-6, IL-10 and TNF-α levels in peripheral blood. Participants received NMES to bilateral lower extremity muscles (quadriceps, tibialis anterior, gastrocnemius) for 30 min. Blood samples immediately pre- and post-NMES were drawn at 15-min intervals to 2-h follow-up, and the mean values of pre-NMES levels were compared to peak and trough post-NMES levels. For cytokines with significant changes, we conducted a repeated-measures linear regression analysis. We also measured post-NMES lactate and creatine kinase levels. RESULTS We enrolled nine eligible participants. There was a significant increase in peak IL-6 from the mean pre-NMES value [0·65 (0·89) to 1·04 (0·89) pg ml-1 , P = 0·001] and a significant decrease in trough IL-1 [0·08 (0·07) to 0·02 (0·02) pg ml-1 , P = 0·041] and TNF-α [2·42 (0·54) to 2·16 (0·59) pg ml-1 , P = 0·021]. In repeated-measures regression analysis, we identified significantly higher mean IL-6 values throughout the full 120 min post-NMES period, and a significantly higher mean IL-1 value at 30 min post-NMES. There were no significant differences in peak IL-10, trough IL-6, lactate, or creatine kinase values. CONCLUSIONS In nine healthy humans, 30 min of NMES was temporally associated with changes in cytokines similar to the effects of active exercise and may mediate NMES' observed effects on reducing muscle weakness.
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Affiliation(s)
- Alexander D Truong
- Pulmonary, Allergy and Critical Care Medicine, Emory University, Atlanta, GA, USA
| | - Michelle E Kho
- Department of Physical Medicine and Rehabilitation, Johns Hopkins University, Baltimore, MD, USA.,School of Rehabilitation Science, McMaster University, Hamilton, ON, Canada
| | - Roy G Brower
- Division of Pulmonary and Critical Care Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Dorianne R Feldman
- Department of Physical Medicine and Rehabilitation, Johns Hopkins University, Baltimore, MD, USA
| | - Elizabeth Colantuoni
- Division of Pulmonary and Critical Care Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Dale M Needham
- Department of Physical Medicine and Rehabilitation, Johns Hopkins University, Baltimore, MD, USA.,Division of Pulmonary and Critical Care Medicine, Johns Hopkins University, Baltimore, MD, USA.,Outcomes After Critical Illness and Surgery (OACIS) Group, Johns Hopkins University, Baltimore, MD, USA
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10
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Iron supplementation effectively suppresses gastrocnemius muscle lesions to improve exercise capacity in chronic heart failure rats with anemia. Nutrition 2015; 31:1038-44. [PMID: 26059380 DOI: 10.1016/j.nut.2015.02.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Revised: 02/13/2015] [Accepted: 02/27/2015] [Indexed: 12/18/2022]
Abstract
OBJECTIVE For patients with chronic heart failure (CHF), exertional fatigue is one of the most common and debilitating symptoms. However, the poor relationship between heart dysfunction and exercise capacity has been ascribed to peripheral abnormalities. Several previous studies confirmed that iron supplementation could significantly improve the exercise capacity of patients with CHF, although they did not analyze effects in the musculoskeletal system. The aim of this study was to investigate the effect of iron treatment on gastrocnemius muscles of CHF rats with anemia. METHODS Male Sprague-Dawley rats were subjected to coronary ligation to induce heart failure. At the same time, blood (1-1.5 mL) was withdrawn from the retro-orbital plexus once every week to induce anemia. After 6 wk of this process, iron dextran was administered to the CHF rats with anemia (CHFa rats) at the dose of 8, 16, 32, or 64 mg/kg every 2 d for 2 wk. RESULTS Iron dextran (8 mg/kg every 2 d) effectively improved hemodynamic parameters (P < 0.05) compared with CHFa rats. Similarly, this dose of iron dextran significantly reduced the ratio of heart weight to body weight (P < 0.01), whereas it significantly increased the distance run (m) to exhaustion (P < 0.01). Iron dextran effectively inhibited sarcoplasmic vacuolation and muscle atrophy of gastrocnemius muscles in CHFa rats, as evaluated by pathologic examinations. Other iron treatments, however, were found to be ineffective on the same parameters, so particular focus was placed on the iron dextran (8 mg/kg every 2 d) group in subsequent analyses. Consistently, phospho-p38 in gastrocnemius muscles of CHFa rats was markedly suppressed by iron dextran. Additionally, iron dextran significantly decreased c-fos and c-jun and up-regulated cellular FLICE-inhibitory protein expression levels.
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Hwee DT, Kennedy AR, Hartman JJ, Ryans J, Durham N, Malik FI, Jasper JR. The small-molecule fast skeletal troponin activator, CK-2127107, improves exercise tolerance in a rat model of heart failure. J Pharmacol Exp Ther 2015; 353:159-68. [PMID: 25678535 DOI: 10.1124/jpet.114.222224] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Heart failure-mediated skeletal myopathy, which is characterized by muscle atrophy and muscle metabolism dysfunction, often manifests as dyspnea and limb muscle fatigue. We have previously demonstrated that increasing Ca(2+) sensitivity of the sarcomere by a small-molecule fast skeletal troponin activator improves skeletal muscle force and exercise performance in healthy rats and models of neuromuscular disease. The objective of this study was to investigate the effect of a novel fast skeletal troponin activator, CK-2127107 (2-aminoalkyl-5-N-heteroarylpyrimidine), on skeletal muscle function and exercise performance in rats exhibiting heart failure-mediated skeletal myopathy. Rats underwent a left anterior descending coronary artery ligation, resulting in myocardial infarction and a progressive decline in cardiac function [left anterior descending coronary artery heart failure (LAD-HF)]. Compared with sham-operated control rats, LAD-HF rat hindlimb and diaphragm muscles exhibited significant muscle atrophy. Fatigability was increased during repeated in situ isokinetic plantar flexor muscle contractions. CK-2127107 produced a leftward shift in the force-Ca(2+) relationship of skinned, single diaphragm, and extensor digitorum longus fibers. Exercise performance, which was assessed by rotarod running, was lower in vehicle-treated LAD-HF rats than in sham controls (116 ± 22 versus 193 ± 31 seconds, respectively; mean ± S.E.M.; P = 0.04). In the LAD-HF rats, a single oral dose of CK-2127107 (10 mg/kg p.o.) increased running time compared with vehicle treatment (283 ± 47 versus 116 ± 22 seconds; P = 0.0004). In summary, CK-2127107 substantially increases exercise performance in this heart failure model, suggesting that modulation of skeletal muscle function by a fast skeletal troponin activator may be a useful therapeutic in heart failure-associated exercise intolerance.
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Affiliation(s)
| | | | | | - Julie Ryans
- Cytokinetics Inc., South San Francisco, California
| | | | - Fady I Malik
- Cytokinetics Inc., South San Francisco, California
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12
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Thibault R, Meyer P, Cano N. Activité physique, nutrition, et insuffisance cardiaque chronique. NUTR CLIN METAB 2014. [DOI: 10.1016/j.nupar.2014.10.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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13
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Grans CF, Feriani DJ, Abssamra MEV, Rocha LY, Carrozzi NM, Mostarda C, Figueroa DM, Angelis KD, Irigoyen MC, Rodrigues B. Resistance training after myocardial infarction in rats: its role on cardiac and autonomic function. Arq Bras Cardiol 2014; 103:60-8. [PMID: 25014059 PMCID: PMC4126762 DOI: 10.5935/abc.20140093] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Accepted: 02/24/2014] [Indexed: 12/17/2022] Open
Abstract
Background Although resistance exercise training is part of cardiovascular rehabilitation
programs, little is known about its role on the cardiac and autonomic function
after myocardial infarction. Objective To evaluate the effects of resistance exercise training, started early after
myocardial infarction, on cardiac function, hemodynamic profile, and autonomic
modulation in rats. Methods Male Wistar rats were divided into four groups: sedentary control, trained
control, sedentary infarcted and trained infarcted rats. Each group with n = 9
rats. The animals underwent maximum load test and echocardiography at the
beginning and at the end of the resistance exercise training (in an adapted
ladder, 40% to 60% of the maximum load test, 3 months, 5 days/week). At the end,
hemodynamic, baroreflex sensitivity and autonomic modulation assessments were
made. Results The maximum load test increased in groups trained control (+32%) and trained
infarcted (+46%) in relation to groups sedentary control and sedentary infarcted.
Although no change occurred regarding the myocardial infarction size and systolic
function, the E/A ratio (-23%), myocardial performance index (-39%) and systolic
blood pressure (+6%) improved with resistance exercise training in group trained
infarcted. Concomitantly, the training provided additional benefits in the high
frequency bands of the pulse interval (+45%), as well as in the low frequency band
of systolic blood pressure (-46%) in rats from group trained infarcted in relation
to group sedentary infarcted. Conclusion Resistance exercise training alone may be an important and safe tool in the
management of patients after myocardial infarction, considering that it does not
lead to significant changes in the ventricular function, reduces the global
cardiac stress, and significantly improves the vascular and cardiac autonomic
modulation in infarcted rats.
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Affiliation(s)
| | | | | | - Leandro Yanase Rocha
- Laboratório do Movimento Humano, Universidade São Judas Tadeu, São Paulo, SP, Brazil
| | | | - Cristiano Mostarda
- Departamento de Educação Física, Universidade Federal do Maranhão, São Luís, MA, Brazil
| | - Diego Mendrot Figueroa
- Laboratório de Hipertensão Experimental, Instituto do Coração, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Kátia De Angelis
- Laboratório de Fisiologia Translacional, Universidade Nove de Julho, São Paulo, SP, Brazil
| | - Maria Cláudia Irigoyen
- Laboratório de Hipertensão Experimental, Instituto do Coração, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Bruno Rodrigues
- Laboratório do Movimento Humano, Universidade São Judas Tadeu, São Paulo, SP, Brazil
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Abstract
In the assessment of dyspnea one has to take into account both the patient's own experience of the symptom and the clinicians observations of breathing rates, sounds and effort to get a complete picture. In addition, to choose appropriate treatment, the underlying cause of dyspnea needs to be assessed. While tools for clinical evaluation of heart failure have gained great interest in research and found a place in guidelines and clinical practice, the same cannot be said for instruments to assess patient self-reported dyspnea. To date, no specific dyspnea rating tool has been recommend over another. Reports from clinical practice are lacking and large; international studies in this field are warranted.
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Affiliation(s)
- Barbro Kjellström
- Cardiology Unit, Department of Medicine, Karolinska Institutet, Stockholm, Sweden.
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Ekman I, Kjellström B, Falk K, Norman J, Swedberg K. Impact of device-guided slow breathing on symptoms of chronic heart failure: a randomized, controlled feasibility study. Eur J Heart Fail 2014; 13:1000-5. [DOI: 10.1093/eurjhf/hfr090] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Inger Ekman
- Institute of Health and Care Sciences, the Sahlgrenska Academy; University of Gothenburg; Sweden
- Centre for Person-centered Care, (GPCC); University of Gothenburg; Sweden
| | - Barbro Kjellström
- Department of Cardiology; the Karolinska institute; Stockholm Sweden
| | - Kristin Falk
- Institute of Health and Care Sciences, the Sahlgrenska Academy; University of Gothenburg; Sweden
| | - Jonna Norman
- Institute of Health and Care Sciences, the Sahlgrenska Academy; University of Gothenburg; Sweden
| | - Karl Swedberg
- Centre for Person-centered Care, (GPCC); University of Gothenburg; Sweden
- Department of Emergency and Cardiovascular Medicine, the Sahlgrenska Academy; University of Gothenburg; Sweden
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16
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Kuniyoshi RR, Martinelli M, Negrão CE, Siqueira SF, Rondon MUPB, Trombetta IC, Kuniyoshi FHS, Laterza MC, Nishioka SAD, Costa R, Tamaki WT, Crevelari ES, Peixoto GDL, Ramires JAF, Kalil R. Effects of cardiac resynchronization therapy on muscle sympathetic nerve activity. PACING AND CLINICAL ELECTROPHYSIOLOGY: PACE 2013; 37:11-8. [PMID: 23952584 DOI: 10.1111/pace.12254] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Revised: 06/26/2013] [Accepted: 07/01/2013] [Indexed: 11/27/2022]
Abstract
INTRODUCTION Muscle sympathetic nerve activity (MSNA) is an independent prognostic marker in patients with heart failure (HF). Therefore, its relevance to the treatment of HF patients is unquestionable. OBJECTIVES In this study, we investigated the effects of cardiac resynchronization therapy (CRT) on MSNA response at rest and during exercise in patients with advanced HF. METHODS We assessed 11 HF patients (51 ± 3.4 years; New York Heart Association class III-IV; left ventricular ejection fraction 27.8 ± 2.2%; optimal medical therapy) submitted to CRT. Evaluations were made prior to and 3 months after CRT. MSNA was performed at rest and during moderate static exercise (handgrip). Peak oxygen consumption (VO2 ) was evaluated by means of cardiopulmonary exercise test. HF patients with advanced NYHA class without CRT and healthy individuals were also studied. RESULTS CRT reduced MSNA at rest (48.9 ± 11.1 bursts/min vs 33.7 ± 15.3 bursts/min, P < 0.05) and during handgrip exercise (MSNA 62.3 ± 13.1 bursts/min vs 46.9 ± 14.3 bursts/min, P < 0.05). Among HF patients submitted to CRT, the peak VO2 increased (12.9 ± 2.8 mL/kg/min vs 16.5 ± 3.9 mL/kg/min, P < 0.05) and an inverse correlation between peak VO2 and resting MSNA (r = -0.74, P = 0.01) was observed. CONCLUSIONS In patients with advanced HF and severe systolic dysfunction: (1) a significant reduction of MSNA (at rest and during handgrip) occurred after CRT, and this behavior was significantly superior to HF patients receiving only medical therapy; (2) MSNA reduction after CRT had an inverse correlation with O2 consumption outcomes.
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17
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Brum P, Bacurau A, Medeiros A, Ferreira J, Vanzelli A, Negrão C. Aerobic exercise training in heart failure: impact on sympathetic hyperactivity and cardiac and skeletal muscle function. Braz J Med Biol Res 2011; 44:827-35. [DOI: 10.1590/s0100-879x2011007500075] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2011] [Accepted: 06/06/2011] [Indexed: 01/01/2023] Open
Affiliation(s)
| | | | - A. Medeiros
- Universidade de São Paulo, Brasil; Universidade Federal de São Paulo, Brasil
| | | | | | - C.E. Negrão
- Universidade de São Paulo, Brasil; Universidade de São Paulo, Brasil
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18
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Munkvik M, Lunde PK, Aronsen JM, Birkeland JAK, Sjaastad I, Sejersted OM. Attenuated fatigue in slow twitch skeletal muscle during isotonic exercise in rats with chronic heart failure. PLoS One 2011; 6:e22695. [PMID: 21799933 PMCID: PMC3143175 DOI: 10.1371/journal.pone.0022695] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2010] [Accepted: 07/04/2011] [Indexed: 01/08/2023] Open
Abstract
During isometric contractions, slow twitch soleus muscles (SOL) from rats with chronic heart failure (chf) are more fatigable than those of sham animals. However, a muscle normally shortens during activity and fatigue development is highly task dependent. Therefore, we examined the development of skeletal muscle fatigue during shortening (isotonic) contractions in chf and sham-operated rats. Six weeks following coronary artery ligation, infarcted animals were classified as failing (chf) if left ventricle end diastolic pressure was >15 mmHg. During isoflurane anaesthesia, SOL with intact blood supply was stimulated (1s on 1s off) at 30 Hz for 15 min and allowed to shorten isotonically against a constant afterload. Muscle temperature was maintained at 37°C. In resting muscle, maximum isometric force (F(max)) and the concentrations of ATP and CrP were not different in the two groups. During stimulation, F(max) and the concentrations declined in parallel sham and chf. Fatigue, which was evident as reduced shortening during stimulation, was also not different in the two groups. The isometric force decline was fitted to a bi-exponential decay equation. Both time constants increased transiently and returned to initial values after approximately 200 s of the fatigue protocol. This resulted in a transient rise in baseline tension between stimulations, although this effect which was less prominent in chf than sham. Myosin light chain 2s phosphorylation declined in both groups after 100 s of isotonic contractions, and remained at this level throughout 15 min of stimulation. In spite of higher energy demand during isotonic than isometric contractions, both shortening capacity and rate of isometric force decline were as well or better preserved in fatigued SOL from chf rats than in sham. This observation is in striking contrast to previous reports which have employed isometric contractions to induce fatigue.
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Affiliation(s)
- Morten Munkvik
- Institute for Experimental Medical Research, Oslo University Hospital, Ullevål, Oslo, Norway
- Center for Heart Failure Research, University of Oslo, Oslo, Norway
| | - Per Kristian Lunde
- Institute for Experimental Medical Research, Oslo University Hospital, Ullevål, Oslo, Norway
- Center for Heart Failure Research, University of Oslo, Oslo, Norway
| | - Jan Magnus Aronsen
- Institute for Experimental Medical Research, Oslo University Hospital, Ullevål, Oslo, Norway
- Center for Heart Failure Research, University of Oslo, Oslo, Norway
| | - Jon Arne Kro Birkeland
- Institute for Experimental Medical Research, Oslo University Hospital, Ullevål, Oslo, Norway
- Center for Heart Failure Research, University of Oslo, Oslo, Norway
| | - Ivar Sjaastad
- Institute for Experimental Medical Research, Oslo University Hospital, Ullevål, Oslo, Norway
- Center for Heart Failure Research, University of Oslo, Oslo, Norway
- Department of Cardiology, Oslo University Hospital, Ullevål, Oslo, Norway
| | - Ole M. Sejersted
- Institute for Experimental Medical Research, Oslo University Hospital, Ullevål, Oslo, Norway
- Center for Heart Failure Research, University of Oslo, Oslo, Norway
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19
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Reichart DL, Hinkle RT, Lefever FR, Dolan ET, Dietrich JA, Sibley DR, Isfort RJ. Activation of the dopamine 1 and dopamine 5 receptors increase skeletal muscle mass and force production under non-atrophying and atrophying conditions. BMC Musculoskelet Disord 2011; 12:27. [PMID: 21269506 PMCID: PMC3038169 DOI: 10.1186/1471-2474-12-27] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2009] [Accepted: 01/26/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Control of skeletal muscle mass and force production is a complex physiological process involving numerous regulatory systems. Agents that increase skeletal muscle cAMP levels have been shown to modulate skeletal muscle mass and force production. The dopamine 1 receptor and its closely related homolog, the dopamine 5 receptor, are G-protein coupled receptors that are expressed in skeletal muscle and increase cAMP levels when activated. Thus we hypothesize that activation of the dopamine 1 and/or 5 receptor will increase skeletal muscle cAMP levels thereby modulating skeletal muscle mass and force production. METHODS We treated isolated mouse tibialis anterior (TA) and medial gastrocnemius (MG) muscles in tissue bath with the selective dopamine 1 receptor and dopamine 5 receptor agonist SKF 81297 to determine if activation of skeletal muscle dopamine 1 and dopamine 5 receptors will increase cAMP. We dosed wild-type mice, dopamine 1 receptor knockout mice and dopamine 5 receptor knockout mice undergoing casting-induced disuse atrophy with SKF 81297 to determine if activation of the dopamine 1 and dopamine 5 receptors results in hypertrophy of non-atrophying skeletal muscle and preservation of atrophying skeletal muscle mass and force production. RESULTS In tissue bath, isolated mouse TA and MG muscles responded to SKF 81297 treatment with increased cAMP levels. Treating wild-type mice with SKF 81297 reduced casting-induced TA and MG muscle mass loss in addition to increasing the mass of non-atrophying TA and MG muscles. In dopamine 1 receptor knockout mice, extensor digitorum longus (EDL) and soleus muscle mass and force was not preserved during casting with SKF 81297 treatment, in contrast to significant preservation of casted wild-type mouse EDL and soleus mass and EDL force with SKF 81297 treatment. Dosing dopamine 5 receptor knockout mice with SKF 81297 did not significantly preserve EDL and soleus muscle mass and force although wild-type mouse EDL mass and force was significantly preserved SKF 81297 treatment. CONCLUSIONS These data demonstrate for the first time that treatment with a dopamine 1/5 receptor agonist results in (1) significant preservation of EDL, TA, MG and soleus muscle mass and EDL muscle force production during periods of atrophy and (2) hypertrophy of TA and MG muscle. These effects appear to be mainly mediated by both the dopamine 1 and dopamine 5 receptors.
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20
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Toth MJ, Ward K, van der Velden J, Miller MS, Vanburen P, Lewinter MM, Ades PA. Chronic heart failure reduces Akt phosphorylation in human skeletal muscle: relationship to muscle size and function. J Appl Physiol (1985) 2010; 110:892-900. [PMID: 21193562 DOI: 10.1152/japplphysiol.00545.2010] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Patients with chronic heart failure (HF) frequently lose muscle mass and function during the course of the disease. A reduction in anabolic stimuli to the muscle has been put forth as a potential mechanism underlying these alterations. The present study examined the hypothesis that skeletal muscle tissue from HF patients would show reduced IGF-1 expression and phosphorylation of signaling molecules downstream of receptor activation. To isolate the unique effect of HF on these variables, we limited the confounding effects of muscle disuse and/or acute disease exacerbation by recruiting controls (n = 11) with similar physical activity levels as HF patients (n = 11) and by testing patients at least 6 mo following any bouts of disease exacerbation/hospitalization. IGF-1 expression in skeletal muscle was similar between patients and controls. Despite this, HF patients were characterized by reduced levels of phospho-Akt/Akt (S473; -43%; P < 0.05), whereas no differences were found in total Akt protein content or phospho- or total protein content of mammalian target of rapamycin (mTOR; S2448), glycogen synthase kinase-3β (GSK-3β; S9), eukaryotic translation initiation factor 4E binding protein-1 (eIF4E-BP; T37/46), p70 ribosomal S6 kinase (p70 S6K; T389), or eIF2Bε (S540). Reduced phospho-Akt/Akt levels and phospho-mTOR/mTOR were related to decreased skeletal muscle myosin protein content (r = 0.602; P < 0.02) and knee extensor isometric torque (r = 0.550; P < 0.05), respectively. Because patients and controls were similar for age, muscle mass, and physical activity, we ascribe the observed alterations in Akt phosphorylation and its relationship to myosin protein content to the unique effects of the HF syndrome.
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Affiliation(s)
- Michael J Toth
- Health Science Research Facility, Univ. of Vermont, Burlington, VT 05405, USA
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21
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Jaussaud J, Blanc P, Bordachar P, Roudaut R, Douard H. Response to cardiac resynchronization therapy: the muscular metabolic pathway. Cardiol Res Pract 2010; 2011:830279. [PMID: 21197405 PMCID: PMC3010693 DOI: 10.4061/2011/830279] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2010] [Accepted: 11/23/2010] [Indexed: 12/21/2022] Open
Abstract
Background. Changes in peripheral muscle in heart failure lead to a shift from aerobic to early anaerobic metabolism during exercise leading to ergoreflex overactivation and exaggerated hyperventilation evaluated by the VE/VCO2 slope. Methods. 50 patients (38 males, 59 ± 12 years) performed cardio-pulmonary exercise test with gaz exchange measurement and echocardiographic evaluation before and 6 months after CRT. Results. The peak respiratory exchange (VCO2/ VO2) ratio was significantly reduced from 1.16 ± 0.14 to 1.11 ± 0.07 (P < .05) and the time to the anaerobic threshold was increased from 153 ± 82 to 245 ± 140 seconds (P = .01). Peak VO2, VE/VCO2, peak circulatory power and NYHA were improved after CRT (13 ± 4 to16 ± 5 ml/kg/min (P < .05), 45 ± 16 to 39 ± 13 (P < .01), 1805 ± 844 to 2225 ± 1171 mmHg.ml/kg/min (P < .01) and 3 ± 0.35 to 1.88 ± 0.4 (P = .01)). In addition, left ventricular ejection fraction and end-systolic volumes were improved from 24 ± 8 to 29 ± 7% (P < .01) and from 157 ± 69 to 122 ± 55 ml (P < .01). Conclusion. We suggest that CRT leads to an increase in oxidative muscular metabolism and postponed anaerobic threshold reducing exaggerated hyperventilation during exercise.
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Affiliation(s)
- Jérémie Jaussaud
- Division de Cardiologie Clinique, Hôpital Cardiologique, du Haut Lévêque, CHU de Bordeaux, Avenue Magellan, 33600 Pessac, France
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22
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Hwang CL, Chien CL, Wu YT. Resistance training increases 6-minute walk distance in people with chronic heart failure: a systematic review. J Physiother 2010; 56:87-96. [PMID: 20482475 DOI: 10.1016/s1836-9553(10)70038-2] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
QUESTION Does resistance training, either alone or as an adjunct to aerobic training, improve cardiac function, exercise capacity and quality of life in people with chronic heart failure? DESIGN Systematic review with meta-analysis of randomised trials. PARTICIPANTS Adults with stable chronic heart failure. INTERVENTION Progressive resistance exercise training, alone or as an adjunct to aerobic training. OUTCOME MEASURES Cardiac function, exercise capacity and quality of life. RESULTS 241 participants from eight trials performed 2 to 6 months of moderate-intensity resistance training (50-75% of 1RM). Most programs consisted of 5 to 6 exercises for large limb and trunk muscles with two sets of 8 to 12 repetitions, three times a week. Resistance training significantly increased 6-minute walk distance (WMD 52 m, 95% CI 19 to 85) but not peak oxygen consumption (WMD 1.4 ml/kg/min, 95% CI -0.3 to 3.1). When used as an adjunct to aerobic training, resistance training did not significantly alter left ventricular ejection fraction (WMD -0.5%, 95% CI -4.3 to 3.3), peak oxygen consumption (WMD -0.7 ml/kg/min, 95% CI -2.3 to 1.0), or Minnesota Living with Heart Failure Questionnaire scores (WMD -0.9, 95% CI -5.4 to 3.7), compared with aerobic training alone. CONCLUSION Resistance training increased 6-minute walk distance compared to no training, but had no other benefits on cardiac function, exercise capacity, or quality of life if used alone or as an adjunct to aerobic training in people with chronic heart failure. However, further high quality, large scale, randomised trials are needed.
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23
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Toth MJ, Shaw AO, Miller MS, VanBuren P, LeWinter MM, Maughan DW, Ades PA. Reduced knee extensor function in heart failure is not explained by inactivity. Int J Cardiol 2009; 143:276-82. [PMID: 19327849 DOI: 10.1016/j.ijcard.2009.02.040] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2009] [Accepted: 02/27/2009] [Indexed: 11/30/2022]
Abstract
BACKGROUND The goal of this study was to determine if heart failure alters knee extensor muscle torque, power production or contractile velocity. METHODS Heart failure patients (n=11; 70.4±4.3 yrs) and controls (n=11; 70.3±3.4 yrs) matched for age and sex were evaluated for knee extensor contractile performance under isometric and isokinetic conditions and body composition by dual energy X-ray absorptiometry. Additionally, we recruited sedentary to minimally active elderly controls to match heart failure patients for habitual physical activity and assessed activity levels using accelerometry. RESULTS Groups did not differ for total or regional body composition or average daily physical activity level. Despite similar muscle size and use, heart failure patients exhibited 21-29% lower (P<0.05 to P<0.01) isometric knee extensor torque throughout a range of knee angles, 15-33% lower (P=0.05 to P<0.01) peak concentric torque measured at various isokinetic speeds and corresponding reductions (P=0.05 to P<0.01) in peak power output. Expression of peak isokinetic torque data relative to isometric torque eliminated group differences, suggesting that impaired contractile function under dynamic conditions is explained by deficits in the force generating capacity of muscle. No group differences were found in the time required to reach target velocity during isokinetic contractions, an index of contractile velocity. CONCLUSION Because group differences in muscle torque were independent of age, sex, physical activity level and muscle size, our results suggest that muscle contractile dysfunction in these patients is likely attributable to the heart failure syndrome.
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Affiliation(s)
- Michael J Toth
- Department of Medicine, University of Vermont, College of Medicine Burlington, VT 05405, United States.
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24
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Okada Y, Toth MJ, Vanburen P. Skeletal muscle contractile protein function is preserved in human heart failure. J Appl Physiol (1985) 2008; 104:952-7. [PMID: 18202167 DOI: 10.1152/japplphysiol.01072.2007] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Skeletal muscle weakness is a common finding in patients with chronic heart failure (CHF). This functional deficit cannot be accounted for by muscle atrophy alone, suggesting that the syndrome of heart failure induces a myopathy in the skeletal musculature. To determine whether decrements in muscle performance are related to alterations in contractile protein function, biopsies were obtained from the vastus lateralis muscle of four CHF patients and four control patients. CHF patients exhibited reduced peak aerobic capacity and knee extensor muscle strength. Decrements in whole muscle strength persisted after statistical control for muscle size. Thin filaments and myosin were isolated from biopsies and mechanically assessed using the in vitro motility assay. Isolated skeletal muscle thin-filament function, however, did not differ between CHF patients and controls with respect to unloaded shortening velocity, calcium sensitivity, or maximal force. Similarly, no difference in maximal force or unloaded shortening velocity of isolated myosin was observed between CHF patients and controls. From these results, we conclude that skeletal contractile protein function is unaltered in CHF patients. Other factors, such as a decrease in total muscle myosin content, are likely contributors to the skeletal muscle strength deficit of heart failure.
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Affiliation(s)
- Yoko Okada
- Univ. of Vermont, College of Medicine, Burlington, VT 05405, USA.
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25
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Abstract
Repeated, intense use of muscles leads to a decline in performance known as muscle fatigue. Many muscle properties change during fatigue including the action potential, extracellular and intracellular ions, and many intracellular metabolites. A range of mechanisms have been identified that contribute to the decline of performance. The traditional explanation, accumulation of intracellular lactate and hydrogen ions causing impaired function of the contractile proteins, is probably of limited importance in mammals. Alternative explanations that will be considered are the effects of ionic changes on the action potential, failure of SR Ca2+release by various mechanisms, and the effects of reactive oxygen species. Many different activities lead to fatigue, and an important challenge is to identify the various mechanisms that contribute under different circumstances. Most of the mechanistic studies of fatigue are on isolated animal tissues, and another major challenge is to use the knowledge generated in these studies to identify the mechanisms of fatigue in intact animals and particularly in human diseases.
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26
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Braith RW, Beck DT. Resistance exercise: training adaptations and developing a safe exercise prescription. Heart Fail Rev 2007; 13:69-79. [DOI: 10.1007/s10741-007-9055-9] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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27
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Williams MA, Haskell WL, Ades PA, Amsterdam EA, Bittner V, Franklin BA, Gulanick M, Laing ST, Stewart KJ. Resistance exercise in individuals with and without cardiovascular disease: 2007 update: a scientific statement from the American Heart Association Council on Clinical Cardiology and Council on Nutrition, Physical Activity, and Metabolism. Circulation 2007; 116:572-84. [PMID: 17638929 DOI: 10.1161/circulationaha.107.185214] [Citation(s) in RCA: 712] [Impact Index Per Article: 41.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Prescribed and supervised resistance training (RT) enhances muscular strength and endurance, functional capacity and independence, and quality of life while reducing disability in persons with and without cardiovascular disease. These benefits have made RT an accepted component of programs for health and fitness. The American Heart Association recommendations describing the rationale for participation in and considerations for prescribing RT were published in 2000. This update provides current information regarding the (1) health benefits of RT, (2) impact of RT on the cardiovascular system structure and function, (3) role of RT in modifying cardiovascular disease risk factors, (4) benefits in selected populations, (5) process of medical evaluation for participation in RT, and (6) prescriptive methods. The purpose of this update is to provide clinicians with recommendations to facilitate the use of this valuable modality.
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28
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Li P, Waters RE, Redfern SI, Zhang M, Mao L, Annex BH, Yan Z. Oxidative phenotype protects myofibers from pathological insults induced by chronic heart failure in mice. THE AMERICAN JOURNAL OF PATHOLOGY 2007; 170:599-608. [PMID: 17255328 PMCID: PMC1851852 DOI: 10.2353/ajpath.2007.060505] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The fiber specificity of skeletal muscle abnormalities in chronic heart failure (CHF) has not been defined. We show here that transgenic mice (8 weeks old) with cardiac-specific overexpression of calsequestrin developed CHF (50.9% decrease in fractional shortening and 56.4% increase in lung weight, P<0.001), cachexia (37.8% decrease in body weight, P<0.001), and exercise intolerance (69.3% decrease in running distance to exhaustion, P<0.001) without a significant change in muscle fiber-type composition. Slow oxidative soleus muscle maintained muscle mass, whereas fast glycolytic tibialis anterior and plantaris muscles underwent atrophy (11.6 and 13.3%, respectively; P<0.05). In plantaris muscle, glycolytic type IId/x and IIb, but not oxidative type I and IIa, fibers displayed significant decreases in cross-sectional area (20.3%, P<0.05). Fast glycolytic white vastus lateralis muscle showed sarcomere degeneration and decreased cytochrome c oxidase IV (39.5%, P<0.01) and peroxisome proliferator-activated receptor gamma co-activator 1alpha protein expression (30.3%, P<0.01) along with a dramatic induction of the MAFbx/Atrogin-1 mRNA. These findings suggest that exercise intolerance can occur in CHF without fiber type switching in skeletal muscle and that oxidative phenotype renders myofibers resistant to pathological insults induced by CHF.
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Affiliation(s)
- Ping Li
- Division of Cardiology, Department of Medicine, Duke University Medical Center, 4321 Medical Park Dr., Suite 200, Durham, NC 27704, USA
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29
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Abstract
This work summarizes our knowledge of the physiological basis of fatigue and the effects of exercise and pharmacological interventions on fatigue. Fatigue may be defined as physical and/or mental weariness resulting from exertion, that is, an inability to continue exercise at the same intensity with a resultant deterioration in performance. The concept of deconditioning in patients is discussed as well as the implications for their rehabilitation and exercise. Because fatigue may result from a number of causes, including loss of muscle mass, deconditioning, nutritional deficiencies, oxygen delivery, and anemia, it should be treated comprehensively. Antifatigue therapy should be the standard of care for most chronic conditions associated with fatigue.
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Affiliation(s)
- William J Evans
- Nutrition, Metabolism, and Exercise Laboratory, University of Arkansas for Medical Sciences, Central Arkansas Veterans Healthcare System, Little Rock, Arkansas 72205, USA
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30
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Toth MJ, Palmer BM, LeWinter MM. Effect of heart failure on skeletal muscle myofibrillar protein content, isoform expression and calcium sensitivity. Int J Cardiol 2006; 107:211-9. [PMID: 16412799 DOI: 10.1016/j.ijcard.2005.03.024] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2004] [Revised: 01/28/2005] [Accepted: 03/11/2005] [Indexed: 11/21/2022]
Abstract
BACKGROUND Alterations in skeletal muscle with heart failure contribute to exercise intolerance and physical disability. The majority of studies to date have examined abnormalities in skeletal muscle oxidative capacity and mitochondrial function. In contrast, less information is available regarding the effect of heart failure on myofibrillar protein metabolism and function. To address this issue, we examined the effect of heart failure on skeletal muscle myofibrillar protein content, isoform distribution and Ca2+ sensitivity. METHODS We measured skeletal muscle myosin heavy chain (MHC) and actin protein content and MHC isoform distribution in soleus (SOL), extensor digitorum longus (EDL), plantaris (PL) and diaphragm (DIA) muscles and myofibrillar Ca2+ sensitivity in EDL muscles from Dahl salt-sensitive rats with (high-salt fed: HS; n=10) or without heart failure (low-salt fed: LS; n=8) and assessed the relationship of these variables to markers of disease severity. RESULTS No differences in muscle mass were found. Similarly, no differences in MHC (mean+/-SE; SOL: 1353+/-29 vs. 1247+/-52; EDL: 1471+/-31 vs. 1441+/-31; PL: 1207+/-66 vs. 1286+/-36; DIA: 1166+/-42 vs. 1239+/-26 AU/microg protein) or actin (EDL: 348+/-13 vs. 358+/-19; PL: 245+/-20 vs. 242+/-9; DIA: 383+/-9 vs. 376+/-17 AU/microg protein) protein content or the actin-to-MHC ratio were observed, with the exception of lower (P<0.01) actin content in the soleus of LS rats (352+/-7 vs. 310+/-8 AU/microg protein). MHC isoform expression (I, IIa, IIx, IIb) did not differ between groups in SOL (I: 89+/-1% vs. 85+/-2%; IIa: 11+/-1% vs. 15+/-2%), EDL (IIx: 43+/-10% vs. 38+/-10%; IIb: 57+/-10% vs. 62+/-10%), PL (I: 6+/-4% vs. 3+/-3%; IIa: 1+/-1% vs. 1+/-1%; IIx: 31+/-3% vs. 26+/-4%; IIb: 62+/-5% vs. 71+/-6%) or DIA (I: 43+/-6% vs. 36+/-6 %; IIa: 9+/-1% vs. 7+/-1%; IIx: 47+/-6% vs. 56+/-7%; IIb: 2+/-1% vs. 1+/-0.5%) muscles. Moreover, heart failure did not affect the Ca2+ sensitivity (i.e., pCa50) of extensor digitorum longus myofilaments (5.68+/-0.11 vs. 5.65+/-0.09). Finally, MHC and actin content, MHC isoform distribution and myofibrillar Ca2+ sensitivity were not related to markers of disease severity. CONCLUSIONS Our results show that this animal model of heart failure is not characterized by alterations in the quantity or isoform distribution of key skeletal muscle myofibrillar proteins or the Ca2+ sensitivity of isometric force production. These findings suggest that alterations in skeletal muscle myofibrillar protein metabolism do not develop in parallel with myocardial failure in the Dahl salt-sensitive rat.
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Affiliation(s)
- Michael J Toth
- Department of Medicine, University of Vermont, Burlington, VT 05405, United States.
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31
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Lunde PK, Sejersted OM, Thorud HMS, Tønnessen T, Henriksen UL, Christensen G, Westerblad H, Bruton J. Effects of Congestive Heart Failure on Ca
2+
Handling in Skeletal Muscle During Fatigue. Circ Res 2006; 98:1514-9. [PMID: 16690878 DOI: 10.1161/01.res.0000226529.66545.e5] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Skeletal muscle weakness and decreased exercise capacity are major symptoms reported by patients with congestive heart failure (CHF). Intriguingly, these skeletal muscle symptoms do not correlate with the decreased heart function. This suggests that CHF leads to maladaptive changes in skeletal muscles, and as reported most markedly in slow-twitch muscles. We used rats at 6 weeks after infarction to measure expression of key proteins involved in SR Ca
2+
release and uptake in slow-twitch soleus muscles. We also measured force and myoplasmic free [Ca
2+
] ([Ca
2+
]
i
) in intact single fibers of soleus muscles. CHF rats showed clear signs of severe cardiac dysfunction with marked increases in heart weight and left ventricular end-diastolic pressure compared with sham operated rats (Sham). There were small, but significant, changes in the content of proteins involved in cellular Ca
2+
handling in CHF muscles: slight increases in SR Ca
2+
release channels (ie, the ryanodine receptors) and in SR Ca
2+
-ATPase. Tetanic force and [Ca
2+
]
i
were not significantly different between CHF and Sham soleus fibers under resting conditions. However, during the stimulation period there was a decrease in tetanic force without changes in [Ca
2+
]
i
in CHF fibers that was not observed in Sham fibers. The fatigue-induced changes recovered rapidly. We conclude that CHF soleus fibers fatigue more rapidly than Sham fibers because of a reversible fatigue-induced decrease in myofibrillar function.
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Affiliation(s)
- Per Kristian Lunde
- Institute for Experimental Medical Research, Ullevål University Hospital, N-0407 Oslo, Norway.
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32
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Toth MJ, Ades PA, Tischler MD, Tracy RP, LeWinter MM. Immune activation is associated with reduced skeletal muscle mass and physical function in chronic heart failure. Int J Cardiol 2006; 109:179-87. [PMID: 16024109 DOI: 10.1016/j.ijcard.2005.06.006] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2005] [Accepted: 06/04/2005] [Indexed: 11/21/2022]
Abstract
BACKGROUND Chronic heart failure is characterized by immune activation and increased circulating levels of cytokines. Whether humoral factors contribute to the peripheral manifestations of the heart failure syndrome, such as muscle atrophy and reduced physical work capacity, however, is not clear. METHODS We measured circulating cytokines (tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6)), their soluble receptors (sTNF-alpha RII, IL-6sR), markers of immune activation (C-reactive protein (CRP)), muscle mass, aerobic capacity and muscle strength in 10 patients with heart failure (mean +/- S.E.; 63 +/- 3 years) and 11 controls (70 +/- 3 years). RESULTS Heart failure patients exhibited decreased aerobic capacity (P < 0.01) and leg muscle strength (P < 0.05). Reduced muscle strength persisted in heart failure patients after statistical adjustment for differences in skeletal muscle size. All inflammatory markers were increased in heart failure patients (P < or = 0.05 to P < 0.01) compared to controls, with the exception of TNF-alpha. Despite no group differences in TNF-alpha, higher concentrations of this cytokine were correlated to lower skeletal muscle mass in the combined study population (range of r-values: -0.436 to -0.545; P < 0.05 to P < 0.02), as were IL-6 levels (range of r-values: -0.438 to -0.443; P < 0.05). TNF-alpha, sTNF-alpha RII, IL-6 and CRP showed strong negative relationships to aerobic capacity (range of r-values: -0.579 to -0.751; P < 0.01 to P < 0.001). In addition, elevated levels of IL-6 and TNF-alpha were associated with reduced leg and forearm skeletal muscle strength (range of r-values: -0.440 to -0.674; P < 0.05 to P < 0.01). Finally, correlations between cytokines and functional measures were present when heart failure patients were analyzed separately (range of r-values: -0.646 to -0.673; P < 0.05). CONCLUSIONS Our results suggest that circulating cytokines are related to both skeletal muscle mass and physical function. These findings provide further evidence to support the hypothesis that immune activation contributes to skeletal muscle atrophy and reduced functional capacity in heart failure patients.
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Affiliation(s)
- Michael J Toth
- Department of Medicine, University of Vermont, Burlington, 05405, USA.
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33
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Lee L, Campbell R, Scheuermann-Freestone M, Taylor R, Gunaruwan P, Williams L, Ashrafian H, Horowitz J, Fraser AG, Clarke K, Frenneaux M. Metabolic modulation with perhexiline in chronic heart failure: a randomized, controlled trial of short-term use of a novel treatment. Circulation 2006; 112:3280-8. [PMID: 16301359 DOI: 10.1161/circulationaha.105.551457] [Citation(s) in RCA: 249] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND Chronic heart failure (CHF) is a major cause of morbidity and mortality that requires a novel approach to therapy. Perhexiline is an antianginal drug that augments glucose metabolism by blocking muscle mitochondrial free fatty acid uptake, thereby increasing metabolic efficiency. We assessed the effects of perhexiline treatment in CHF patients. METHODS AND RESULTS In a double-blind fashion, we randomly assigned patients with optimally medicated CHF to either perhexiline (n=28) or placebo (n=28). The primary end point was peak exercise oxygen consumption (VO2max), an important prognostic marker. In addition, the effect of perhexiline on myocardial function and quality of life was assessed. Quantitative stress echocardiography with tissue Doppler measurements was used to assess regional myocardial function in patients with ischemic CHF. 31P magnetic resonance spectroscopy was used to assess the effect of perhexiline on skeletal muscle energetics in patients with nonischemic CHF. Treatment with perhexiline led to significant improvements in VO2max (16.1+/-0.6 to 18.8+/-1.1 mL . kg(-1) . min(-1); P<0.001), quality of life (Minnesota score reduction from 45+/-5 to 34+/-5; P=0.04), and left ventricular ejection fraction (24+/-1% to 34+/-2%; P<0.001). Perhexiline treatment also increased resting and peak dobutamine stress regional myocardial function (by 15% and 24%, respectively) and normalized skeletal muscle phosphocreatine recovery after exercise. There were no adverse effects during the treatment period. CONCLUSIONS In patients with CHF, metabolic modulation with perhexiline improved VO2max, left ventricular ejection fraction, symptoms, resting and peak stress myocardial function, and skeletal muscle energetics. Perhexiline may therefore represent a novel treatment for CHF with a good safety profile, provided that the dosage is adjusted according to plasma levels.
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Affiliation(s)
- Leong Lee
- Department of Cardiology, University of Nottingham, Queens Medical Centre, Nottingham, England
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34
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Reid MB, Andrade FH, Balke CW, Esser KA. Redox mechanisms of muscle dysfunction in inflammatory disease. Phys Med Rehabil Clin N Am 2005; 16:925-49, ix. [PMID: 16214052 DOI: 10.1016/j.pmr.2005.08.016] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Michael B Reid
- Department of Physiology, University of Kentucky Medical Center, 800 Rose Street, MS-509, Lexington, KY 40536-0298, USA.
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35
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Thorud HMS, Verburg E, Lunde PK, Strømme TA, Sjaastad I, Sejersted OM. Temperature-dependent skeletal muscle dysfunction in rats with congestive heart failure. J Appl Physiol (1985) 2005; 99:1500-7. [PMID: 15932960 DOI: 10.1152/japplphysiol.00807.2004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Abnormalities in the excitation-contraction coupling of slow-twitch muscle seem to explain the slowing and increased fatigue observed in congestive heart failure (CHF). However, it is not known which elements of the excitation-contraction coupling might be affected. We hypothesize that the temperature sensitivity of contractile properties of the soleus muscle might be altered in CHF possibly because of alterations of the temperature sensitivity of intracellular Ca(2+) handling. We electrically stimulated the in situ soleus muscle of anesthetised rats that had 6-wk postinfarction CHF using 1 and 50 Hz and using a fatigue protocol (5-Hz stimulation for 30 min) at 35, 37, and 40 degrees C. Ca(2+) uptake and release were measured in sarcoplasmic reticulum vesicles at various temperatures. Contraction and relaxation rates of the soleus muscle were slower in CHF than in sham at 35 degrees C, but the difference was almost absent at 40 degrees C. The fatigue protocol revealed that force development was more temperature sensitive in CHF, whereas contraction and relaxation rates were less temperature sensitive in CHF than in sham. The Ca(2+) uptake and release rates did not correlate to the difference between CHF and sham regarding contractile properties or temperature sensitivity. In conclusion, the discrepant results regarding altered temperature sensitivity of contraction and relaxation rates in the soleus muscle of CHF rats compared with Ca(2+) release and uptake rates in vesicles indicate that the molecular cause of slow-twitch muscle dysfunction in CHF is not linked to the intracellular Ca(2+) cycling.
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Affiliation(s)
- H-M Schiøtz Thorud
- Institute for Experimental Medical Research, Ullevaal University Hospital, Oslo, Norway
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36
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Schiøtz Thorud HM, Lunde PK, Nicolaysen G, Nicolaysen A, Helge JW, Nilsson GE, Sejersted OM. Muscle dysfunction during exercise of a single skeletal muscle in rats with congestive heart failure is not associated with reduced muscle blood supply. ACTA ACUST UNITED AC 2004; 181:173-81. [PMID: 15180789 DOI: 10.1111/j.1365-201x.2004.01285.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIM Inadequate muscle blood flow is a possible explanation for reduced fatigue resistance in patients with congestive heart failure (CHF). METHODS In rats with post-infarction CHF we electrically stimulated the soleus muscle (SOL) in situ with intact blood supply. Contractile properties, blood flow, high-energy phosphates and metabolites were measured during 30 min of intermittent stimulation, and in addition capillarization of SOL was recorded. RESULTS During stimulation, SOL contracted more slowly in rats with CHF compared with sham-operated rats. However, the blood flow in SOL was unaltered and capillary density was maintained in CHF rats. Further, the content of ATP, ADP, AMP, NAD, CrP, P(i) and lactate in SOL was not different between the groups. CONCLUSION The cause of contractile dysfunction in a single exercising skeletal muscle in rats with CHF cannot be explained simply by reduced blood supply. In addition, absence of changes in high-energy phosphates and metabolites indicate that the oxidative metabolism of SOL is intact in rats with CHF.
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Affiliation(s)
- H-M Schiøtz Thorud
- Institute for Experimental Medical Research, Ullevaal University Hospital, and Centre for Heart Failure Research, University of Oslo, Oslo, Norway
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37
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Helwig B, Schreurs KM, Hansen J, Hageman KS, Zbreski MG, McAllister RM, Mitchell KE, Musch TI. Training-induced changes in skeletal muscle Na+-K+ pump number and isoform expression in rats with chronic heart failure. J Appl Physiol (1985) 2003; 94:2225-36. [PMID: 12562669 DOI: 10.1152/japplphysiol.00279.2002] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The mechanisms responsible for the decrements in exercise performance in chronic heart failure (CHF) remain poorly understood, but it has been suggested that sarcolemmal alterations could contribute to the early onset of muscular fatigue. Previously, our laboratory demonstrated that the maximal number of ouabain binding sites (B(max)) is reduced in the skeletal muscle of rats with CHF (Musch TI, Wolfram S, Hageman KS, and Pickar JG. J Appl Physiol 92: 2326-2334, 2002). These reductions may coincide with changes in the Na(+)-K(+)-ATPase isoform (alpha and beta) expression. In the present study, we tested the hypothesis that reductions in B(max) would coincide with alterations in the alpha- and beta-subunit expression of the sarcolemmal Na(+)-K(+)-ATPase of rats with CHF. Moreover, we tested the hypothesis that exercise training would increase B(max) along with producing significant changes in alpha- and beta-subunit expression. Rats underwent a sham operation (sham; n = 10) or a surgically induced myocardial infarction followed by random assignment to either a control (MI; n = 16) or exercise training group (MI-T; n = 16). The MI-T rats performed exercise training (ET) for 6-8 wk. Hemodynamic indexes demonstrated that MI and MI-T rats suffered from severe left ventricular dysfunction and congestive CHF. Maximal oxygen uptake (Vo(2 max)) and endurance capacity (run time to fatigue) were reduced in MI rats compared with sham. B(max) in the soleus and plantaris muscles and the expression of the alpha(2)-isoform of the Na(+)-K(+)-ATPase in the red portion of the gastrocnemius (gastrocnemius(red)) muscle were reduced in MI rats. After ET, Vo(2 max) and run time to fatigue were increased in the MI-T group of rats. This coincided with increases in soleus and plantaris B(max) and the expression of the alpha(2)-isoform in the gastrocnemius(red) muscle. In addition, the expression of the beta(2)-isoform of the gastrocnemius(red) muscle was increased in the MI-T rats compared with their sedentary counterparts. This study demonstrates that CHF-induced alterations in skeletal muscle Na(+)-K(+)-ATPase, including B(max) and isoform expression, can be partially reversed by ET.
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Affiliation(s)
- Bryan Helwig
- Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas 66506-5802, USA
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38
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Nicoletti I, Cicoira M, Zanolla L, Franceschini L, Brighetti G, Pilati M, Zardini P. Skeletal muscle abnormalities in chronic heart failure patients: relation to exercise capacity and therapeutic implications. CONGESTIVE HEART FAILURE (GREENWICH, CONN.) 2003; 9:148-54. [PMID: 12826773 DOI: 10.1111/j.1527-5299.2002.01219.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Recent studies suggest that changes in the periphery, like those occurring in the skeletal muscles of patients with chronic heart failure, might play an important role in the origin of symptoms and exercise intolerance in this condition. Biochemical and histologic changes in the skeletal muscles of chronic heart failure patients relate with the degree of exercise intolerance better than hemodynamics parameters. A reduction in skeletal muscle mass represents another important determinant of exercise intolerance in chronic heart failure patients. The relationship between skeletal muscle changes and exercise intolerance suggests the possibility of modifying the peripheral changes in order to improve functional capacity in chronic heart failure patients. Recent studies have shown that the administration of angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers can improve the properties of the skeletal muscles. Similarly, exercise training allows improvement in peak oxygen consumption, which parallels important biochemical and histologic changes in the skeletal muscles.
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Affiliation(s)
- Ilaria Nicoletti
- Dipartimento di Scienze Biomediche e Chirurgiche, Sezione di Cardiologia, Universita degli Studi di Verona, Verona, Italy
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39
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Maurer M, Katz SD, LaManca J, Manandhar M, Mancini D. Dissociation between exercise hemodynamics and exercise capacity in patients with chronic heart failure and marked increase in ejection fraction after treatment with beta-adrenergic receptor antagonists. Am J Cardiol 2003; 91:356-60. [PMID: 12565100 DOI: 10.1016/s0002-9149(02)03171-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Affiliation(s)
- Mathew Maurer
- Division of Circulatory Physiology, Columbia Presbyterian Medical Center, New York, New York, USA.
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40
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Cortes CW, Thompson PD, Moyna NM, Schluter MD, Leskiw MJ, Donaldson MR, Duncan BH, Stein TP. Protein kinetics in stable heart failure patients. J Appl Physiol (1985) 2003; 94:295-300. [PMID: 12391030 DOI: 10.1152/japplphysiol.00654.2001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Heart failure (HF) is a slow progressive syndrome characterized by low cardiac output and peripheral metabolic, biochemical, and histological alterations. Protein loss and reduced protein turnover occur with aging, but the consequences of congestive HF (CHF) superimposed on the normal aging response are unknown. This study has two objectives: 1) to determine whether there was a difference between older age-matched controls and those with stable HF (i.e., ischemic pathology) in whole body protein turnover and 2) to determine whether protein metabolism in liver and skeletal muscle protein turnover is impacted by CHF. We measured the whole body protein synthesis rate with a U-(15)N-labeled algal protein hydrolysate in 10 patients with CHF and in 10 age-matched controls. Muscle fractional synthesis rate of lateral vastus muscle was determined with [U-(13)C]alanine on muscle biopsies obtained by a standard percutaneous needle biopsy technique. Fractional synthesis rates of five plasma proteins of hepatic origin (fibrinogen, complement C-3, ceruloplasmin, transferrin, and very low-density lipoprotein apoliprotein B-100) were determined by using (2)H(5)-labeled l-phenylalanine as tracer. Results showed that whole body protein synthesis rate was reduced in CHF patients (3.09 +/- 0.19 vs. 2.25 +/- 0.71 g protein x kg(-1) x day(-1), P < 0.05) as was muscle fractional synthesis rate (3.02 +/- 0.58 vs. 1.33 +/- 0.71%/day, P < 0.05) and very low-density lipoprotein apoliprotein B-100 (265 +/- 25 vs. 197 +/- 16%/day, P < 0.05). CHF patients were hyperinsulinemic (9.6 +/- 3.1 vs. 47.0 +/- 7.8 microU/ml, P < 0.01). The results were compared with those found with bed rest patients. In conclusion, protein turnover is depressed in CHF patients, and both skeletal muscle and liver are impacted. These results are similar to those found with bed rest, which suggests that inactivity is a factor in depressed protein metabolism.
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Affiliation(s)
- Charles W Cortes
- Division of Preventive Cardiology, Hartford Hospital, Connecticut 06102, USA.
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41
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Vibarel N, Hayot M, Ledermann B, Messner Pellenc P, Ramonatxo M, Prefaut C. Effect of aerobic exercise training on inspiratory muscle performance and dyspnoea in patients with chronic heart failure. Eur J Heart Fail 2002; 4:745-51. [PMID: 12453545 DOI: 10.1016/s1388-9842(02)00163-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Nancy Vibarel
- Laboratoire de Physiologie des Interactions, Service Central de Physiologie Clinique, Unité d'Exploration Respiratoire, Centre Hospitalier Arnaud de Villeneuve, Montpellier, France.
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Abstract
The cachexia syndrome is characterised by progressive weight loss and depletion of lean body mass and has long been recognised as a poor prognostic sign. Whilst the clinical features of the wasting process are readily apparent, its pathogenesis is complex and poorly understood. There is increasing evidence that the immune system, in particular inflammatory cytokines, may play an important role in the development of cachexia. The cytokine considered to be the most relevant to this process is tumor necrosis factor alpha (TNF), although other mediators such as interleukin (IL) 1, IL-6 and interferon gamma have also been implicated. Apoptosis represents a potential pathway by which wasting can occur in chronic diseases. Cytokines and their corresponding receptors are known to be important regulators of cell death. Apoptosis has been demonstrated in the skeletal muscle of patients with chronic heart failure (CHF) and is thought to be partly responsible for the significant impairment of functional work capacity associated with this condition. An understanding of the mechanisms that regulate muscle protein breakdown is essential for the development of strategies for treating or even preventing muscle cachexia in patients. It is the aim of this article to review the role of inflammatory cytokines, particularly TNF, in the pathogenesis of wasting and also the potential for anti-cytokine therapy. Although this review will concentrate predominantly on the syndrome of CHF, other chronic illnesses such as liver disease, cancer, and sepsis will also be discussed.
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Affiliation(s)
- Rakesh Sharma
- Department of Clinical Cardiology, National Heart and Lung Institute, Imperial College School of Medicine, London, UK
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43
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Musch TI, Wolfram S, Hageman KS, Pickar JG. Skeletal muscle ouabain binding sites are reduced in rats with chronic heart failure. J Appl Physiol (1985) 2002; 92:2326-34. [PMID: 12015343 DOI: 10.1152/japplphysiol.00686.2001] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Intrinsic skeletal muscle abnormalities decrease muscular endurance in chronic heart failure (CHF). In CHF patients, the number of skeletal muscle Na(+)-K(+) pumps that have a high affinity for ouabain (i.e., the concentration of [(3)H]ouabain binding sites) is reduced, and this reduction is correlated with peak oxygen uptake. The present investigation determined whether the concentration of skeletal muscle [(3)H]ouabain binding sites found during CHF is related to 1) severity of the disease state, 2) muscle fiber type composition, and/or 3) endurance capacity. Four muscles were chosen that represented slow-twitch oxidative (SO), fast-twitch oxidative glycolytic (FOG), fast-twitch glycolytic (FG), and mixed fiber types. Measurements were obtained 8-10 wk postsurgery in 23 myocardial infarcted (MI) and 18 sham-operated control (sham) rats. Eighteen rats had moderate left ventricular (LV) dysfunction [LV end-diastolic pressure (LVEDP) < 20 mmHg], and five had severe LV dysfunction (LVEDP > 20 mmHg). Rats with severe LV dysfunction had significant pulmonary congestion and were likely in a chronic state of compensated congestive failure as indicated by an approximately twofold increase in both lung and right ventricle weight. Run time to fatigue and maximal oxygen uptake (VO(2 max)) were significantly reduced ( downward arrow39 and downward arrow28%, respectively) in the rats with severe LV dysfunction and correlated with the magnitude of LV dysfunction as indicated by LVEDP (run time: r = 0.60, n = 21, P < 0.01 and VO(2 max): r = 0.93, n = 13, P < 0.01). In addition, run time to fatigue was significantly correlated with VO(2 max) (r = 0.87, n = 15, P < 0.01). The concentration of [(3)H]ouabain binding sites (B(max)) was significantly reduced (21-28%) in the three muscles comprised primarily of oxidative fibers [soleus: 259 +/- 14 vs. 188 +/- 17; plantaris: 295 +/- 17 vs. 229 +/- 18; red portion of gastrocnemius: 326 +/- 17 vs. 260 +/- 14 pmol/g wet tissue wt]. In addition, B(max) was significantly correlated with VO(2 max) (soleus: r = 0.54, n = 15, P < 0.05; plantaris: r = 0.59, n = 15, P < 0.05; red portion of gastrocnemius: r = 0.65, n = 15, P < 0.01). These results suggest that downregulation of Na(+)-K(+) pumps that possess a high affinity for ouabain in oxidative skeletal muscle may play an important role in the exercise intolerance that attends severe LV dysfunction in CHF.
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Affiliation(s)
- Timothy I Musch
- Department of Anatomy, Kansas State University, Manhattan, Kansas 66506-5802, USA.
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44
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Lunde PK, Verburg E, Eriksen M, Sejersted OM. Contractile properties of in situ perfused skeletal muscles from rats with congestive heart failure. J Physiol 2002; 540:571-80. [PMID: 11956344 PMCID: PMC2290250 DOI: 10.1113/jphysiol.2001.013324] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
We hypothesized that in congestive heart failure (CHF) slow-twitch but not fast-twitch muscles exhibit decreased fatigue resistance in the sense of accelerated reduction of muscle force during activity. Experiments were carried out on anaesthetized rats 6 weeks after induction of myocardial infarction or a sham operation (Sham). Animals with left ventricular end-diastolic pressure (LVEDP) > 15 mmHg under anaesthesia were selected for the CHF group. There was no muscle atrophy in CHF. Force generation by in situ perfused soleus (Sol) or extensor digitorum longus (EDL) muscles was recorded during stimulation (trains at 5 Hz for 6 s (Sol) or 10 Hz for 1.5 s (EDL) at 10 or 2.5 s intervals, respectively) for 1 h in Sol and 10 min in EDL at 37 degrees C. Initial force was almost the same in Sol from CHF and Sham rats, but relaxation was slower in CHF. Relaxation times (95-5 % of peak force) were 177 +/- 55 and 131 +/- 44 ms in CHF and Sham, respectively, following the first stimulation train. After 2 min of stimulation the muscles transiently became slower and maximum relaxation times were 264 +/- 71 and 220 +/- 45 ms in CHF and Sham, respectively (P < 0.05). After 60 min they recovered to 204 +/- 60 and 122 +/- 55 ms in CHF and Sham, respectively (P < 0.05). In CHF but not in Sham rats the force of contraction of Sol declined from the second to the sixtieth minute to 70 % of peak force. The EDL of both CHF and Sham fatigued to 24-28 % of initial force, but no differences in contractility pattern were detected. Thus, slow-twitch muscle is severely affected in CHF by slower than normal relaxation and significantly reduced fatigue resistance, which may explain the sensation of both muscle stiffness and fatigue in CHF patients.
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Affiliation(s)
- Per Kristian Lunde
- Institute for Experimental Medical Research, University of Oslo, Ullevaal University Hospital, N-0407 Oslo, Norway
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45
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Sharma R, Anker S. From tissue wasting to cachexia: changes in peripheral blood flow and skeletal musculature. Eur Heart J Suppl 2002. [DOI: 10.1093/ehjsupp/4.suppl_d.d12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Zajac A, Tomkiewicz L, Podolec P, Tracz W, Malec E. Cardiorespiratory response to exercise in children after modified fontan operation. SCAND CARDIOVASC J 2002; 36:80-5. [PMID: 12028869 DOI: 10.1080/140174302753675348] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
OBJECTIVE Examination of exercise function of Fontan patients and comparison with healthy control subjects. DESIGN Fourteen patients (6 males, 8 females; age: 5.7-17 years, mean 8.1 years) after Fontan repair in New York Heart Association (NYHA) class I with rest O(2)sat > 85% requiring no cardiovascular medications performed graded exercises on a treadmill 0.5-3.2 years postoperatively (mean 1.8 years). During the tests the heart and respiratory rate, blood pressure, oxygen uptake, carbon dioxide production, minute ventilation, tidal volume and O(2)sat were recorded. Spirometry was performed before and during exercise. RESULTS The peak VO(2)max in Fontan patients was significantly reduced compared with controls (p = 0.0002). Other parameters: anaerobic threshold (p = 0.0001); pulsO(2) (p = 0.00005); peak minute ventilation (p = 0.0014); physiological dead space to tidal volume ratio at peak exercise (p = 0.0004); maximal work rate (p = 0.00008); exercise time (p = 0.00003) were significantly reduced in univentricular patients. The heart rate at peak exercise was lower in the patients (p = 0.0003) and O(2)sat dropped significantly (p = 0.003). CONCLUSION The aerobic capacity, work and ventilatory parameters in Fontan patients are markedly reduced compared with controls. The anaerobic threshold was significantly lower. The decreased O(2)sat at peak exercise may suggest intrapulmonary shunting.
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Affiliation(s)
- Andrzej Zajac
- Department of Pediatric Cardiac Surgery, Polish-American Children's Hospital, Kraków, Poland
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47
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Pu CT, Johnson MT, Forman DE, Hausdorff JM, Roubenoff R, Foldvari M, Fielding RA, Singh MA. Randomized trial of progressive resistance training to counteract the myopathy of chronic heart failure. J Appl Physiol (1985) 2001; 90:2341-50. [PMID: 11356801 DOI: 10.1152/jappl.2001.90.6.2341] [Citation(s) in RCA: 175] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Chronic heart failure (CHF) is characterized by a skeletal muscle myopathy not optimally addressed by current treatment paradigms or aerobic exercise. Sixteen older women with CHF were compared with 80 age-matched peers without CHF and randomized to progressive resistance training or control stretching exercises for 10 wk. Women with CHF had significantly lower muscle strength (P < 0.0001) but comparable aerobic capacity to women without CHF. Exercise training was well tolerated and resulted in no changes in resting cardiac indexes in CHF patients. Strength improved by an average of 43.4 +/- 8.8% in resistance trainers vs. -1.7 +/- 2.8% in controls (P = 0.001), muscle endurance by 299 +/- 66% vs. 1 +/- 3% (P = 0.001), and 6-min walk distance by 49 +/- 14 m (13%) vs. -3 +/- 19 m (-3%) (P = 0.03). Increases in type I fiber area (9.5 +/- 16%) and citrate synthase activity (35 +/- 21%) in skeletal muscle were independently predictive of improved 6-min walk distance (r2 = 0.78; P = 0.0024). High-intensity progressive resistance training improves impaired skeletal muscle characteristics and overall exercise performance in older women with CHF. These gains are largely explained by skeletal muscle and not resting cardiac adaptations.
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Affiliation(s)
- C T Pu
- Nutrition, Exercise Physiology, and Sarcopenia Laboratory, Jean Mayer United States Department of Agriculture, Human Nutrition Research Center on Aging, Tufts University, Boston, MA 02111, USA
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Lunde PK, Sjaastad I, Schiøtz Thorud HM, Sejersted OM. Skeletal muscle disorders in heart failure. ACTA PHYSIOLOGICA SCANDINAVICA 2001; 171:277-94. [PMID: 11412140 DOI: 10.1046/j.1365-201x.2001.00830.x] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Heart failure is associated with reduction of exercise capacity that cannot be solely ascribed to reduced maximal oxygen uptake (VdotO2max). Therefore, research has focused on changes in skeletal muscle morphology, metabolism and function. Factors that can cause such changes in skeletal muscle comprise inactivity, malnutrition, constant or repeated episodes of inadequate oxygen delivery and prolonged exposure to altered neurohumoural stimuli. Most of these factors are not specific for the heart failure condition. On the other hand, heart failure is more than one clinical condition. Congestive heart failure (CHF) develops gradually as a result of deteriorating contractility of the viable myocardium, myocardial failure. Is it possible that development of this contractile deficit in the myocardium is paralleled by a corresponding contractile deficit of the skeletal muscles? This question cannot be answered today. Both patient studies and experimental studies support that there is a switch to a faster muscle phenotype and energy metabolism balance is more anaerobic. The muscle atrophy seen in many patients is not so evident in experimental studies. Few investigators have studied contractile function. Both fast twitch and slow twitch muscles seem to become slower, not faster as might be expected, and this is possibly linked to slower intracellular Ca2+ cycling. The neurohumoural stimuli that can cause this change are not known, but recently it has been reported that several cytokines are increased in CHF patients. Thus, the changes seen in skeletal muscles during CHF are partly secondary to inactivity, but the possibility remains that the contractility is altered because of intracellular changes of Ca2+ metabolism that are also seen in the myocardium.
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Affiliation(s)
- P K Lunde
- Institute for Experimental Medical Research, University of Oslo, Ullevaal Hospital, Oslo, Norway
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Li X, Moody MR, Engel D, Walker S, Clubb FJ, Sivasubramanian N, Mann DL, Reid MB. Cardiac-specific overexpression of tumor necrosis factor-alpha causes oxidative stress and contractile dysfunction in mouse diaphragm. Circulation 2000; 102:1690-6. [PMID: 11015349 DOI: 10.1161/01.cir.102.14.1690] [Citation(s) in RCA: 163] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND We have developed a transgenic mouse with cardiac-restricted overexpression of tumor necrosis factor-alpha (TNF-alpha). These mice develop a heart failure phenotype characterized by left ventricular dysfunction and remodeling, pulmonary edema, and elevated levels of TNF-alpha in the peripheral circulation from cardiac spillover. Given that TNF-alpha causes atrophy and loss of function in respiratory muscle, we asked whether transgenic mice developed diaphragm dysfunction and whether contractile losses were caused by oxidative stress or tissue remodeling. METHODS AND RESULTS muscles excised from transgenic mice and littermate controls were studied in vitro with direct electrical stimulation. Cytosolic oxidant levels were measured with 2', 7'-dichlorofluorescin diacetate; emissions of the oxidized product were detected by fluorescence microscopy. Force generation by the diaphragm of transgenic animals was 47% less than control (13.2+/-0. 8 [+/-SEM] versus 25.1+/-0.6 N/cm(2); P:<0.001); this weakness was associated with greater intracellular oxidant levels (P:<0.025) and was partially reversed by 30-minute incubation with the antioxidant N:-acetylcysteine 10 mmol/L (P:<0.01). Exogenous TNF-alpha 500 micromol/L increased oxidant production in diaphragm of wild-type mice and caused weakness that was inhibited by N:-acetylcysteine, suggesting that changes observed in the diaphragm of transgenic animals were mediated by TNF-alpha. There were no differences in body or diaphragm weights between transgenic and control animals, nor was there evidence of muscle injury or apoptosis. CONCLUSIONS Elevated circulating levels of TNF-alpha provoke contractile dysfunction in the diaphragm through an endocrine mechanism thought to be mediated by oxidative stress.
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Affiliation(s)
- X Li
- Baylor College of Medicine and Texas Heart Institute, Houston, TX 77030, USA
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Affiliation(s)
- P H Sugden
- National Heart and Lung Institute (NHLI) Division, Imperial College School of Medicine, London, United Kingdom.
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