Exercise training and high-sensitivity cardiac troponin T in patients with heart failure with reduced ejection fraction

Plasma cell disorders (PCDs) are identified in the clinical lab by detecting the monoclonal immunoglobulin (M-protein) which they produce. Traditionally, serum protein electrophoresis methods have been utilized to detect and isotype Mproteins. Increasing demands to detect low-level disease and new therapeutic monoclonal immunoglobulin treatments have stretched the electrophoretic methods to their analytical limits. Newer techniques based on mass spectrometry (MS) are emerging which have improved clinical and analytical performance. MS is gaining traction into clinical laboratories, and has replaced immunofixation electrophoresis (IFE) in routine practice at one institution. The International Myeloma Working Group (IMWG) Mass Spectrometry Committee reviewed the literature in order to summarize current data and to make recommendations regarding the role of mass spectrometric methods in diagnosing and monitoring patients with myeloma and related disorders. Current literature demonstrates that immune-enrichment of immunoglobulins coupled to intact light chain MALDI-TOF MS has clinical characteristics equivalent in performance to IFE with added benefits of detecting additional risk factors for PCDs, differentiating Mprotein from therapeutic antibodies, and is a suitable replacement for IFE for diagnosing and monitoring multiple myeloma and related PCDs. In this paper we discuss the IMWG recommendations for the use of MS in PCDs.publishedVersio

Moderate continuous or high intensity interval exercise in heart failure with reduced ejection fraction : Differences between ischemic and non-ischemic etiology

publishedVersio

Baseline and exercise predictors of VO2peak in systolic heart failure patients : Results from SMARTEX-HF

Author's accepted version (postprint).This is an Accepted Manuscript of an article published by American College of Sports Medicine in Medicine & Science in Sports & Exercise on 04/11/2019.Available online: https://journals.lww.com/acsm-msse/FullText/2020/04000/Baseline_and_Exercise_Predictors_of_V_O2peak_in.5.aspxacceptedVersio

Role of strength training in the rehabilitation of muscle dysfunctions due to chronic heart failure

L’insuffisance cardiaque chronique est une maladie systémique où des dysfonctions périphériques viennent s’ajouter à l’incapacité du cœur à assurer un débit cardiaque adéquat aux tissus métabolisants. Parmi des dysfonctions périphériques, l’atrophie ainsi que la perte de force et d’endurance musculaire jouent un rôle primordial et contribuent largement à la genèse des symptômes majeurs de l’insuffisance cardiaque chronique, c’est à dire la fatigue, la dyspnée et l’intolérance à l’effort.Ce n’est que depuis le début des années 1990 que des études ont montré que le réentraînement à l’effort pouvait être bénéfique pour le patient insuffisant cardiaque chronique; auparavant, il était considéré comme contre-indiqué.La méthodologie d’entraînement proposée à cette époque aux patients était un entraînement de l’endurance cardio-vasculaire, le renforcement musculaire n’y avait pas sa place car on craignait que l’impact hémodynamique de ce type d’entraînement risquerait de détériorer la fonction cardiaque encore plus. Des études menées sur des contractions musculaires de type isométrique montraient en effet une diminution de la fonction cardiaque pendant l’entraînement. Cependant, les contraintes imposées pendant les exercices de renforcement musculaire dynamique (encore appelés « résistifs ») ne correspondent nullement à celles du renforcement isométrique. Des études sur des personnes saines ont montré que le renforcement musculaire est plus adapté à induire des améliorations du volume et de la force musculaire que l’entraînement de l’endurance cardio-vasculaire.Le but de nos travaux a donc été de vérifier si l’introduction du renforcement musculaire, en complément de l’entraînement cardio-vasculaire ou bien comme entraînement à part entière, pouvait apporter un bénéfice supplémentaire chez l’insuffisant cardiaque chronique par son aptitude, du moins théorique, à mieux corriger certains aspects des dysfonctions musculaires.Il s’agissait, dans les différentes études que nous avons menées, de vérifier qu’un entraînement composé de renforcement musculaire (au moins partiellement) chez le patient insuffisant cardiaque chronique:-\Doctorat en Sciences de la motricitéinfo:eu-repo/semantics/nonPublishe

Role of strength training in the rehabilitation of muscle dysfunctions due to chronic heart failure

L’insuffisance cardiaque chronique est une maladie systémique où des dysfonctions périphériques viennent s’ajouter à l’incapacité du cœur à assurer un débit cardiaque adéquat aux tissus métabolisants. Parmi des dysfonctions périphériques, l’atrophie ainsi que la perte de force et d’endurance musculaire jouent un rôle primordial et contribuent largement à la genèse des symptômes majeurs de l’insuffisance cardiaque chronique, c’est à dire la fatigue, la dyspnée et l’intolérance à l’effort.Ce n’est que depuis le début des années 1990 que des études ont montré que le réentraînement à l’effort pouvait être bénéfique pour le patient insuffisant cardiaque chronique; auparavant, il était considéré comme contre-indiqué.La méthodologie d’entraînement proposée à cette époque aux patients était un entraînement de l’endurance cardio-vasculaire, le renforcement musculaire n’y avait pas sa place car on craignait que l’impact hémodynamique de ce type d’entraînement risquerait de détériorer la fonction cardiaque encore plus. Des études menées sur des contractions musculaires de type isométrique montraient en effet une diminution de la fonction cardiaque pendant l’entraînement. Cependant, les contraintes imposées pendant les exercices de renforcement musculaire dynamique (encore appelés « résistifs ») ne correspondent nullement à celles du renforcement isométrique. Des études sur des personnes saines ont montré que le renforcement musculaire est plus adapté à induire des améliorations du volume et de la force musculaire que l’entraînement de l’endurance cardio-vasculaire.Le but de nos travaux a donc été de vérifier si l’introduction du renforcement musculaire, en complément de l’entraînement cardio-vasculaire ou bien comme entraînement à part entière, pouvait apporter un bénéfice supplémentaire chez l’insuffisant cardiaque chronique par son aptitude, du moins théorique, à mieux corriger certains aspects des dysfonctions musculaires.Il s’agissait, dans les différentes études que nous avons menées, de vérifier qu’un entraînement composé de renforcement musculaire (au moins partiellement) chez le patient insuffisant cardiaque chronique:-\Doctorat en Sciences de la motricitéinfo:eu-repo/semantics/nonPublishe

Motor unit recruitment order during voluntary and electrically induced contractions in the tibialis anterior

The recruitment order of motor units (MU) was compared during voluntary and electrically induced contractions. With the use of spike-triggered averaging, a total of 302 MUs with recruitment thresholds ranging from 1% to 88% of maximal voluntary contraction were recorded in the human tibialis anterior muscle in five subjects. The mean (+/-SD) MU force was 98.3+/-93.3 mN (mean torque 16.8+/-15.9 mNm) and the mean contraction time (CT) 46.2+/-12.7 ms. The correlation coefficients (r) between MU twitch force and CT versus the recruitment threshold in voluntary contractions were +0.68 and -0.38 (P<0.001), respectively. In voluntary contractions, MUs were recruited in order of increasing size except for only 6% of the cases; whereas, during transcutaneous electrical stimulation (ES) at the muscle motor point, MU pairs showed a reversal of recruitment order in 28% and 35% of the observations, respectively, when the pulse durations were 1.0 ms or 0.1 ms. This recruitment reversal during ES was not related to the magnitude of the difference in voluntary recruitment thresholds between MUs. It is concluded that if the reversal of MU recruitment observed during ES is biophysically controlled by differences in their nerve axon input impedance, in percutaneous stimulation at the motor point, other factors such as the size and the morphological organisation of the axonal branches can also influence the order of activation.Journal ArticleResearch Support, Non-U.S. Gov'tinfo:eu-repo/semantics/publishe

Mechanical properties and behaviour of motor units in the tibialis anterior during voluntary contractions

The present work was carried out to analyse the properties and behaviour of Tibialis anterior motor units (MUs) during voluntary contractions in humans. A total of 528 single MU mechanical properties was recorded in 10 subjects by means of the spike-triggered averaging (STA) technique. MU recruitment thresholds and discharge frequencies were recorded during linearly increasing maximal voluntary contraction (MVC). The results indicate a mean (+/- SD) MU torque of 25.5 +/- 21.5 mN.m. and a mean time-to-peak of 45.6 +/- 13.6 ms. A comparison of the average MU twitch torque with that of the muscle allowed an estimate of about 300 MUs in the Tibialis anterior. A positive linear relationship was recorded between the MU twitch torque and the recruitment threshold. The mean minimal and maximal discharge frequencies of MUs were 8.4 +/- 3.0 Hz and 33.2 +/- 14.7 Hz, respectively. The results of the present work indicate that MU behaviour during voluntary contractions is different in the tibialis anterior and in the adductor pollicis.Journal ArticleResearch Support, Non-U.S. Gov'tinfo:eu-repo/semantics/publishe

Exercise training and high-sensitivity cardiac troponin T in patients with heart failure with reduced ejection fraction

Aims Whether an exercise training intervention is associated with reduction in long-term high-sensitivity cardiac troponin T (hs-cTnT) concentration (a biomarker of subclinical myocardial injury) in patients with heart failure with reduced ejection fraction (HFrEF) is unknown. The aims were to determine (i) the effect of a 12 week endurance exercise training intervention with different training intensities on hs-cTnT in stable patients with HFrEF (left ventricular ejection fraction ≤ 35%) and (ii) associations between hs-cTnT and peak oxygen uptake (VO2peak). Methods and results In this sub-study of the SMARTEX-HF trial originally including 261 patients from nine European centres, 213 eligible patients were included after withdrawals and appropriate exclusions [19% women, mean age 61.2 years (standard deviation: 11.9)], randomized to high-intensity interval training (HIIT; n = 77), moderate continuous training (MCT; n = 63), or a recommendation of regular exercise (RRE; n = 73). Hs-cTnT measurements and clinical data acquired before (BL) and after a 12 week exercise training intervention (12 weeks) and at 1 year follow-up (1 year) were analysed using multivariable mixed models. Baseline hs-cTnT was above the 99th percentile upper reference limit of 14 ng/L in 35 (48%), 35 (56%), and 49 (64%) patients in the RRE, MCT, and HIIT groups, respectively. Median hs-cTnT was 16 ng/L at BL, 14 ng/L at 12 weeks, and 14 ng/L at 1 year. Hs-cTnT was statistically significantly reduced at 12 weeks in a model adjusted for randomization group, centre and VO2peak, and after further adjustment in the final model that also included age, sex, creatinine concentrations, N-terminal pro-brain natriuretic peptide, smoking, and heart failure treatment. The mean reduction from BL to 12 weeks in the final model was 1.1 ng/L (95% confidence interval: 1.0–1.2 ng/L, P < 0.001), and the reduction was maintained at 1 year with a mean reduction from BL to 1 year of 1.1 ng/L (95% confidence interval: 1.0–1.1 ng/L, P = 0.025). Randomization group was not associated with hs-cTnT at any time point (overall test: P = 0.20, MCT vs. RRE: P = 0.81, HIIT vs. RRE: P = 0.095, interaction time × randomization group: P = 0.88). Independent of time point, higher VO2peak correlated with lower hs-cTnT (mean reduction over all time points: 0.2 ng/L per increasing mL·kg−1·min−1, P = 0.002), without between-group differences (P = 0.19). Conclusions In patients with stable HFrEF, a 12 week exercise intervention was associated with reduced hs-cTnT in all groups when adjusted for clinical variables. Higher VO2peak correlated with lower hs-cTnT, suggesting a positive long-term effect of increasing VO2peak on subclinical myocardial injury in HFrEF, independent of training programme

Exercise training and high-sensitivity cardiac troponin T in patients with heart failure with reduced ejection fraction

Plasma cell disorders (PCDs) are identified in the clinical lab by detecting the monoclonal immunoglobulin (M-protein) which they produce. Traditionally, serum protein electrophoresis methods have been utilized to detect and isotype Mproteins. Increasing demands to detect low-level disease and new therapeutic monoclonal immunoglobulin treatments have stretched the electrophoretic methods to their analytical limits. Newer techniques based on mass spectrometry (MS) are emerging which have improved clinical and analytical performance. MS is gaining traction into clinical laboratories, and has replaced immunofixation electrophoresis (IFE) in routine practice at one institution. The International Myeloma Working Group (IMWG) Mass Spectrometry Committee reviewed the literature in order to summarize current data and to make recommendations regarding the role of mass spectrometric methods in diagnosing and monitoring patients with myeloma and related disorders. Current literature demonstrates that immune-enrichment of immunoglobulins coupled to intact light chain MALDI-TOF MS has clinical characteristics equivalent in performance to IFE with added benefits of detecting additional risk factors for PCDs, differentiating Mprotein from therapeutic antibodies, and is a suitable replacement for IFE for diagnosing and monitoring multiple myeloma and related PCDs. In this paper we discuss the IMWG recommendations for the use of MS in PCDs