RESUMEN
Gravity has had a significant impact on the evolution of life on Earth with organisms developing necessary biological adaptations over billions of years to counter this ever-existing force. There has been an exponential increase in experiments using real and simulated gravity environments in the recent years. Although an understanding followed by discovery of counter measures to negate diminished gravity in space had been the driving force of research initially, there has since been a phenomenal leap wherein a force unearthly as microgravity is beginning to show promising potential. The current review summarizes pathophysiological changes that occur in multiple aspects of the cardiovascular system when exposed to an altered gravity environment leading to cardiovascular deconditioning and orthostatic intolerance. Gravity influences not just the complex multicellular systems but even the survival of organisms at the molecular level by intervening fundamental cellular processes, directly affecting those linked to actin and microtubule organization via mechano-transduction pathways. The reach of gravity ranges from cytoskeletal rearrangement that regulates cell adhesion and migration to intracellular dynamics that dictate cell fate commitment and differentiation. An understanding that microgravity itself is not present on Earth propels the scope of simulated gravity conditions to be a unique and useful environment that could be explored for enhancing the potential of stem cells for a wide range of applications as has been highlighted here.
Asunto(s)
Adaptación Fisiológica , Ingravidez , Humanos , Animales , Sistema Cardiovascular/fisiopatología , Simulación de Ingravidez , Descondicionamiento Cardiovascular/fisiología , Intolerancia Ortostática/fisiopatología , Vuelo EspacialRESUMEN
Orthostatic hypertension, defined by an increase of systolic blood pressure (SBP) of ≥20 mmHg upon standing, harbors an increased cardiovascular risk. We pooled data from two rigorously conducted head-down tilt bedrest studies to test the hypothesis that cardiopulmonary deconditioning and hypovolemia predispose to orthostatic hypertension. With bedrest, peak VO2 decreased by 6 ± 4 mlO2/min/kg (p < 0.0001) and plasma volume by 367 ± 348 ml (p < 0.0001). Supine SBP increased from 127 ± 9 mmHg before to 133 ± 10 mmHg after bedrest (p < 0.0001). In participants with stable hemodynamics following head-up tilt, the incidence of orthostatic hypertension was 2 out of 67 participants before bedrest and 2 out of 57 after bedrest. We conclude that in most healthy persons, cardiovascular deconditioning and volume loss associated with long-term bedrest are not sufficient to cause orthostatic hypertension.
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Reposo en Cama , Presión Sanguínea , Inclinación de Cabeza , Hipertensión , Volumen Plasmático , Humanos , Masculino , Femenino , Adulto , Reposo en Cama/efectos adversos , Persona de Mediana Edad , Presión Sanguínea/fisiología , Hipertensión/fisiopatología , Descondicionamiento Cardiovascular/fisiología , Hipovolemia/fisiopatología , Hipovolemia/complicaciones , Hemodinámica/fisiología , Consumo de Oxígeno/fisiologíaRESUMEN
Bedrest as an experimental paradigm or as an in-patient stay for medical reasons has negative consequences for cardiovascular health. The effects of severe inactivity parallel many of the changes experienced with natural aging but over a much shorter duration. Cardiac function is reduced, arteries stiffen, neural reflex responses are impaired, and metabolic and oxidative stress responses impose burden on the heart and vascular systems. The effect of these changes is revealed in studies of integrative function. Aerobic fitness progressively deteriorates with bedrest and tolerance of upright posture is rapidly impaired. In this review we consider the similarities of aging and bedrest-induced cardiovascular deconditioning. We concur with many recent clinical recommendations that early and regular mobility with upright posture will reduce likelihood of hospital-associated disability related to bedrest.
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Reposo en Cama , Humanos , Reposo en Cama/efectos adversos , Enfermedades Cardiovasculares/fisiopatología , Enfermedades Cardiovasculares/etiología , Envejecimiento Prematuro/fisiopatología , Envejecimiento Prematuro/etiología , Descondicionamiento Cardiovascular/fisiología , Envejecimiento/fisiologíaRESUMEN
Astronauts in microgravity experience multi-system deconditioning, impacting their inflight efficiency and inducing dysfunctions upon return to Earth gravity. To fill the sex gap of knowledge in the health impact of spaceflights, we simulate microgravity with a 5-day dry immersion in 18 healthy women (ClinicalTrials.gov Identifier: NCT05043974). Here we show that dry immersion rapidly induces a sedentarily-like metabolism shift mimicking the beginning of a metabolic syndrome with a drop in glucose tolerance, an increase in the atherogenic index of plasma, and an impaired lipid profile. Bone remodeling markers suggest a decreased bone formation coupled with an increased bone resorption. Fluid shifts and muscular unloading participate to a marked cardiovascular and sensorimotor deconditioning with decreased orthostatic tolerance, aerobic capacity, and postural balance. Collected datasets provide a comprehensive multi-systemic assessment of dry immersion effects in women and pave the way for future sex-based evaluations of countermeasures.
Asunto(s)
Vuelo Espacial , Ingravidez , Humanos , Femenino , Descondicionamiento Cardiovascular/fisiología , Inmersión , Ingravidez/efectos adversos , Simulación de IngravidezRESUMEN
The nucleus tractus solitarii (nTS) is the major integrative brainstem region for autonomic modulation and processing of cardiovascular reflexes. GABA and glutamate are the main inhibitory and excitatory neurotransmitters, respectively, within this nucleus. Alterations in the GABA-glutamate regulation in the nTS are related to numerous cardiovascular comorbidities. Bedridden individuals and people exposed to microgravity exhibit dysautonomia and cardiovascular deconditioning that are mimicked in the hindlimb unloading (HU) rat model. We have previously shown in the nTS that HU increases glutamatergic neurotransmission yet decreases neuronal excitability. In this study, we investigated the effects of HU on nTS GABAergic neurotransmission. We hypothesized that HU potentiates GABA signaling via increased GABAergic release and postsynaptic GABA receptor expression. Following HU or control postural exposure, GABAergic neurotransmission was assessed using whole cell patch clamp whereas the magnitude of GABA release was evaluated via an intensity-based GABA sensing fluorescence reporter (iGABASnFR). In response to GABA interneuron stimulation, the evoked inhibitory postsynaptic current (nTS-IPSC) amplitude and area, as well as iGABASnFR fluorescence, were greater in HU than in control. HU also elevated the frequency but not the amplitude of spontaneous miniature IPSCs. Picoapplication of GABA produced similar postsynaptic current responses in nTS neurons of HU and control. Moreover, HU did not alter GABAA receptor α1 subunit expression, indicating minimal alterations in postsynaptic membrane receptor expression. These results indicate that HU increases GABAergic signaling in the nTS likely via augmented release of GABA from presynaptic terminals. Altogether, our data indicate GABA plasticity contributes to the autonomic and cardiovascular alterations following cardiovascular deconditioning (CVD).NEW & NOTEWORTHY Gravity influences distribution of blood volume and autonomic function. Microgravity and prolonged bed rest induce cardiovascular deconditioning (CVD). We used hindlimb unloading (HU), a rat analog for bed rest, to investigate CVD-induced neuroplasticity in the brainstem. Our data demonstrate that HU increases GABA modulation of nucleus tractus solitarii (nTS) neurons via presynaptic plasticity. Given the importance of nTS in integrating cardiovascular reflexes, this study provides new evidence on the central mechanisms behind CVD following HU.
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Enfermedades Cardiovasculares , Núcleo Solitario , Animales , Descondicionamiento Cardiovascular , Enfermedades Cardiovasculares/metabolismo , Ácido Glutámico/metabolismo , Humanos , Ratas , Ratas Sprague-Dawley , Receptores de GABA-A/metabolismo , Núcleo Solitario/fisiología , Transmisión Sináptica/fisiología , Ácido gamma-Aminobutírico/metabolismoRESUMEN
Evidence supports early rehabilitation after stroke to limit disability. However, stroke survivors are typically sedentary and experience significant cardiovascular and muscular deconditioning. Despite growing consensus that preclinical and clinical stroke recovery research should be aligned, there have been few attempts to incorporate cardiovascular and skeletal muscle deconditioning into animal models of stroke. Here, we demonstrate in rats that a hindlimb sensorimotor cortex stroke results in both cardiovascular and skeletal muscle deconditioning and impairments in gait akin to those observed in humans. To reduce poststroke behavioral, cardiovascular, and skeletal muscle perturbations, we then used a combinatorial intervention consisting of aerobic and resistance exercise in conjunction with administration of resveratrol (RESV), a drug with exercise mimetic properties. A combination of aerobic and resistance exercise mitigated decreases in cardiovascular fitness and attenuated skeletal muscle abnormalities. RESV, beginning 24 hours poststroke, reduced acute hindlimb impairments, improved recovery in hindlimb function, increased vascular density in the perilesional cortex, and attenuated skeletal muscle fiber changes. Early RESV treatment and aerobic and resistance exercise independently provided poststroke benefits, at a time when individuals are rapidly becoming deconditioned as a result of inactivity. Although no additive effects were observed in these experiments, this approach represents a promising strategy to reduce poststroke behavioral impairments and minimize deconditioning. As such, this treatment regime has potential for enabling patients to engage in more intensive rehabilitation at an earlier time following stroke when mechanisms of neuroplasticity are most prevalent.
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Antioxidantes/farmacología , Descondicionamiento Cardiovascular , Músculo Esquelético , Condicionamiento Físico Animal/fisiología , Recuperación de la Función , Entrenamiento de Fuerza , Resveratrol/farmacología , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular/terapia , Animales , Antioxidantes/administración & dosificación , Conducta Animal/efectos de los fármacos , Conducta Animal/fisiología , Descondicionamiento Cardiovascular/efectos de los fármacos , Descondicionamiento Cardiovascular/fisiología , Terapia Combinada , Modelos Animales de Enfermedad , Femenino , Miembro Posterior/efectos de los fármacos , Miembro Posterior/fisiopatología , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/fisiopatología , Ratas , Ratas Sprague-Dawley , Recuperación de la Función/efectos de los fármacos , Recuperación de la Función/fisiología , Resveratrol/administración & dosificación , Corteza Sensoriomotora/efectos de los fármacos , Corteza Sensoriomotora/fisiopatología , Accidente Cerebrovascular/tratamiento farmacológicoRESUMEN
Patients with end-stage kidney disease (ESKD) are often sedentary and decreased functional capacity associates with mortality. The relationship between cardiovascular disease (CVD) and physical function has not been fully explored. Understanding the relationships between prognostically relevant measures of CVD and physical function may offer insight into how exercise interventions might target specific elements of CVD. 130 patients on haemodialysis (mean age 57 ± 15 years, 73% male, dialysis vintage 1.3 years (0.5, 3.4), recruited to the CYCLE-HD trial (ISRCTN11299707), underwent cardiovascular phenotyping with cardiac MRI (left ventricular (LV) structure and function, pulse wave velocity (PWV) and native T1 mapping) and cardiac biomarker assessment. Participants completed the incremental shuttle walk test (ISWT) and sit-to-stand 60 (STS60) as field-tests of physical function. Linear regression models identified CV determinants of physical function measures, adjusted for age, gender, BMI, diabetes, ethnicity and systolic blood pressure. Troponin I, PWV and global native T1 were univariate determinants of ISWT and STS60 performance. NT pro-BNP was a univariate determinant of ISWT performance. In multivariate models, NT pro-BNP and global native T1 were independent determinants of ISWT and STS60 performance. LV ejection fraction was an independent determinant of ISWT distance. However, age and diabetes had the strongest relationships with physical function. In conclusion, NT pro-BNP, global native T1 and LV ejection fraction were independent CV determinants of physical function. However, age and diabetes had the greatest independent influence. Targeting diabetic care may ameliorate deconditioning in these patients and a multimorbidity approach should be considered when developing exercise interventions.
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Descondicionamiento Cardiovascular , Enfermedades Cardiovasculares/diagnóstico , Tolerancia al Ejercicio , Estado Funcional , Indicadores de Salud , Fallo Renal Crónico/terapia , Diálisis Renal , Adulto , Factores de Edad , Anciano , Biomarcadores/sangre , Enfermedades Cardiovasculares/fisiopatología , Enfermedades Cardiovasculares/terapia , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/fisiopatología , Femenino , Humanos , Fallo Renal Crónico/diagnóstico , Fallo Renal Crónico/fisiopatología , Imagen por Resonancia Cinemagnética , Masculino , Persona de Mediana Edad , Multimorbilidad , Péptido Natriurético Encefálico/sangre , Fragmentos de Péptidos/sangre , Valor Predictivo de las Pruebas , Pronóstico , Análisis de la Onda del Pulso , Ensayos Clínicos Controlados Aleatorios como Asunto , Medición de Riesgo , Factores de Riesgo , Volumen Sistólico , Troponina I/sangre , Rigidez Vascular , Función Ventricular Izquierda , Prueba de PasoRESUMEN
OBJECTIVE: Elderly patients continue to experience low levels of mobility during and following postoperative hospitalization that lead to persistent physical decline. Therefore, here we compared chronic resistance (CR) exercise against chronic aerobic (CA) exercise in ameliorating postoperative functioning and reducing proinflammatory muscular Toll-like receptor (TLR)-associated signaling in elderly postoperative patients. METHODS: We conducted a prospective, randomized trial comparing the effects of 3 exercise programs (CR, CA, and CRâ¯+â¯CA) in 66 elderly patients recovering from recent hip, femur, or pelvic fracture repair surgery. The primary outcomes were changes in anatomic/physical performance parameters (ie, maximal oxygen intake, endurance, quadriceps cross-sectional area, and maximum knee-extensor force). The secondary outcomes were changes in TLR/nuclear factor kappa beta signaling pathway marker expression. RESULTS: Three of the 4 anatomic/physical performance parameters significantly improved for the CR and CRâ¯+â¯CA cohorts. Muscular expression of myeloid differentiation primary response gene 88, transforming growth factor beta-activated kinase 1 (TLR signaling pathway markers), p50, p65, tumor necrosis factor α, and interleukin 6 (nuclear factor kappa beta signaling pathway markers) all showed significant reductions after CR and CRâ¯+â¯CA. Serum expression of 2 key TLR4 ligands, heat shock protein 70 and serum amyloid A, also showed significant reductions after CR and CRâ¯+â¯CA. CONCLUSIONS: Three months of CR or CRâ¯+â¯CA improves maximal oxygen consumption, quadriceps cross-sectional area, and maximum knee-extensor force while lowering muscular proinflammatory signaling markers in elderly adults with postoperative deconditioning.
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Artroplastia de Reemplazo/rehabilitación , Ejercicio Físico/fisiología , Complicaciones Posoperatorias/rehabilitación , Entrenamiento de Fuerza/métodos , Receptores Toll-Like/metabolismo , Anciano , Descondicionamiento Cardiovascular , Femenino , Humanos , Interleucina-6/metabolismo , Masculino , FN-kappa B/metabolismo , Estudios Prospectivos , Recuperación de la Función , Transducción de Señal , Receptor Toll-Like 4/metabolismoRESUMEN
BACKGROUND: Low cardiorespiratory fitness and inactivity are common after lung transplantation (LTx). The causes of exercise intolerance are incompletely understood. OBJECTIVES: The aim of this study was to objectively assess cardiorespiratory fitness and physical activity, evaluate causes of exercise intolerance, and explore clinical factors associated with cardiorespiratory fitness after bilateral LTx (BLTx). MATERIALS AND METHODS: Peak oxygen uptake (VâO2peak) and exercise-limiting factors were evaluated by a treadmill cardiopulmonary exercise test (CPET) 6-60 months after BLTx. Physical activity was measured with accelerometers, and results were compared with Norwegian normative data and the World Health Organization's (WHO) recommendations for physical activity. RESULTS: In 54 included BLTx recipients (mean age 50 ± 15 years, 50% females), VâO2peak (mL × kg-1 × min-1) was 21.8 ± 7.7 for men and 22.4 ± 6.2 for women, corresponding to 57 ± 17 and 70 ± 12% of predicted, respectively. Three patients (6%) met criteria for normal VâO2peak. Deconditioning limited VâO2peak in 22 patients (41%), while ventilatory limitation and abnormal gas exchange were observed in 14 (26%) and 20 (37%) patients, respectively (some had more than 1 finding). Forty-three patients (86%) did not meet the WHO physical activity recommendations. There was a moderate correlation between VâO2peak and physical activity (r = 0.642, p < 0.01). Body mass index, physical activity, forced expiratory volume after 1 second, sex, and hemoglobin together accounted for 73% of the variability in VâO2peak. CONCLUSIONS: Low cardiorespiratory fitness was observed in the majority of BLTx recipients. Both deconditioning and cardiopulmonary limitations were common findings. Nearly 90% were classified as being inactive according to physical activity recommendations. CPET appears to identify a deconditioned subgroup of BLTx recipients for whom exercise training may be especially beneficial.
Asunto(s)
Capacidad Cardiovascular , Ejercicio Físico , Trasplante de Pulmón , Consumo de Oxígeno , Adulto , Anciano , Descondicionamiento Cardiovascular , Estudios de Cohortes , Fibrosis Quística/cirugía , Prueba de Esfuerzo , Tolerancia al Ejercicio , Femenino , Volumen Espiratorio Forzado , Hemoglobinas/metabolismo , Humanos , Enfermedades Pulmonares Intersticiales/cirugía , Masculino , Persona de Mediana Edad , Noruega , Enfermedad Pulmonar Obstructiva Crónica/cirugía , Intercambio Gaseoso Pulmonar , Adulto JovenRESUMEN
Biology experiments in space seek to increase our understanding of what happens to life beyond Earth and how we can safely send life beyond Earth. Spaceflight is associated with many (mal)adaptations in physiology, including decline in musculoskeletal, cardiovascular, vestibular, and immune systems. Biological experiments in space are inherently challenging to implement. Development of hardware and validation of experimental conditions are critical to ensure the collection of high-quality data. The model organism Caenorhabditis elegans has been studied in space for more than 20 years to better understand spaceflight-induced (patho)physiology, particularly spaceflight-induced muscle decline. These experiments have used a variety of hardware configurations. Despite this, hardware used in the past was not available for our most recent experiment, the Molecular Muscle Experiment (MME). Therefore, we had to design and validate flight hardware for MME. MME provides a contemporary example of many of the challenges faced by researchers conducting C. elegans experiments onboard the International Space Station. Here, we describe the hardware selection and validation, in addition to the ground-based experiment scientific validation testing. These experiences and operational solutions allow others to replicate and/or improve our experimental design on future missions.
Asunto(s)
Adaptación Fisiológica , Caenorhabditis elegans/fisiología , Exobiología/instrumentación , Vuelo Espacial , Ingravidez/efectos adversos , Animales , Descondicionamiento Cardiovascular , Diseño de Equipo , Exobiología/métodos , Modelos Animales , Músculos/fisiología , Simulación de Ingravidez/instrumentación , Simulación de Ingravidez/métodosRESUMEN
Human papillomavirus vaccination (HPVV) was included in the national immunization program in 2013 in Japan. However, the Japanese government suspended proactive recommendations 2 months after this decision because various adverse events following the vaccination were reported by the media. More than 6 years have already passed since the suspension of proactive recommendations of all available vaccines in Japan. Although no causal relationship between the adverse effects and HPVV has been confirmed, the Japanese government has not withdrawn the suspension. Thus, it is important to show various possible causes of the adverse events other than HPVV. It is attempted to describe the possible contribution of the misunderstanding regarding the symptoms of postural tachycardia syndrome, deconditioning, and exercise-induced hyperalgesia as the adverse effects of HPVV in this review article.
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Vacunas contra Papillomavirus/efectos adversos , Síndrome de Taquicardia Postural Ortostática/fisiopatología , Vacunación/psicología , Descondicionamiento Cardiovascular , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/psicología , Femenino , Humanos , Hiperalgesia , Japón , Síndrome de Taquicardia Postural Ortostática/etiología , Vacunación/legislación & jurisprudenciaRESUMEN
After a brief semantic and historical presentation, the article presents the main trials and systematic reviews on the tertiary prevention and care of cancers through physical activity. It gives the keys to understanding how, in forty years of research, interventions dedicated to prevent physical inactivity to reduce the risk of cancer have become as indispensable as adapted physical activity (APA) programs for care pathways. If the public health message "move more" with or without cancer remains true, the research encourages practitioners to implement personalized programs in primary prevention, in addition to treatment and prevention of recurrence. As soon as the diagnosis is made, APA programs will become truly supportive care complementary of treatments, in other words non-pharmacological interventions (NPIs), with the aim of improving the quality of life of patients, improving their overall health, reducing side effects of treatment, potentiate the effects of certain treatments, and reduce the risk of recurrence. Research remains to be carried out notably on the survival, on the advanced cancers and on the integrative modelling of the mechanisms involved.
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Ejercicio Físico , Neoplasias/terapia , Tejido Adiposo , Descondicionamiento Cardiovascular , Enfermedades Cardiovasculares/terapia , Fatiga/prevención & control , Humanos , Linfedema/etiología , Linfedema/prevención & control , Recurrencia Local de Neoplasia/prevención & control , Neoplasias/prevención & control , Acondicionamiento Físico Humano , Prevención Primaria , Calidad de Vida , Años de Vida Ajustados por Calidad de Vida , Prevención Secundaria , Conducta Sedentaria , Prevención Terciaria/métodos , Factores de TiempoRESUMEN
It is unclear how high-intensity, interval-type nontraditional exercise training programmes can be feasible and effective options for inactive obese individuals. This randomized controlled trial investigated the hypothesis that a 10-month high-intensity, interval-type neuromuscular training programme (DoIT) with adjunct portable modalities, performed in a small-group setting, induces improvements in psychological well-being, subjective vitality and exercise behavioural regulations in obese women. Associations between adherence, psychological and physiological indicators were also investigated. Forty-nine previously inactive obese females (36.4 ± 4.4 yrs) were randomly assigned to three groups (control; N = 21, 10-month training; N = 14, or 5-month training plus 5 month-detraining; N = 14). DoIT was a supervised, progressive, and time-efficient (<30â min) programme that used 10-12 functional/neuromotor exercises and prescribed work and rest time intervals (20-40 sec) in a circuit fashion (1-3 rounds) for 10 months. Questionnaires were used to measure psychological distress, subjective vitality, and behavioural regulations in exercise at pre-, mid-, and post-intervention. The 10-month training reduced psychological distress (72%, p = 0.001), external regulation (75%, p = 0.011) and increased vitality (53%, p = 0.001), introjected regulation (63%, p = 0.001), intrinsic regulation (33%, p = 0.004), and identified regulation (88%, p = 0.001). A moderate to strong positive relationship was found between adherence rate and identified regulation scores (r = 0.59, p = 0.001) and between VO2peak and identified regulation scores (r = 0.59, p = 0.001). A mild dissociation between exercise intensity and perceived exertion was also observed. Our novel findings suggest that a 10-month implementation of a high-intensity interval neuromuscular training programme promotes positive psychological adaptations provoking exercise behavioural regulation and adherence while inducing weight loss in inactive obese women.
Asunto(s)
Ejercicio Físico/psicología , Entrenamiento de Intervalos de Alta Intensidad/psicología , Obesidad/psicología , Cooperación del Paciente/psicología , Conducta Sedentaria , Pérdida de Peso , Adulto , Descondicionamiento Cardiovascular , Ejercicio en Circuitos/métodos , Ejercicio en Circuitos/psicología , Entrenamiento Aeróbico/métodos , Entrenamiento Aeróbico/psicología , Ejercicio Físico/fisiología , Femenino , Frecuencia Cardíaca , Entrenamiento de Intervalos de Alta Intensidad/métodos , Humanos , Salud Mental , Fuerza Muscular , Obesidad/terapia , Cooperación del Paciente/estadística & datos numéricos , Teoría Psicológica , Estrés Psicológico/diagnóstico , Estrés Psicológico/terapia , Factores de TiempoRESUMEN
Abstract Fluid volume and hemodynamic management in hemodialysis patients is an essential component of dialysis adequacy. Restoring salt and water homeostasis in hemodialysis patients has been a permanent quest by nephrologists summarized by the 'dry weight' probing approach. Although this clinical approach has been associated with benefits on cardiovascular outcome, it is now challenged by recent studies showing that intensity or aggressiveness to remove fluid during intermittent dialysis is associated with cardiovascular stress and potential organ damage. A more precise approach is required to improve cardiovascular outcome in this high-risk population. Fluid status assessment and monitoring rely on four components: clinical assessment, non-invasive instrumental tools (e.g., US, bioimpedance, blood volume monitoring), cardiac biomarkers (e.g. natriuretic peptides), and algorithm and sodium modeling to estimate mass transfer. Optimal management of fluid and sodium imbalance in dialysis patients consist in adjusting salt and fluid removal by dialysis (ultrafiltration, dialysate sodium) and by restricting salt intake and fluid gain between dialysis sessions. Modern technology using biosensors and feedback control tools embarked on dialysis machine, with sophisticated analytics will provide direct handling of sodium and water in a more precise and personalized way. It is envisaged in the near future that these tools will support physician decision making with high potential of improving cardiovascular outcome.
Resumo O volume de fluidos e o controle hemodinâmico em pacientes em hemodiálise é um componente essencial da adequação da diálise. A restauração da homeostase do sal e da água em pacientes em hemodiálise tem sido uma busca constante por parte dos nefrologistas, no que condiz à abordagem do "peso seco. Embora essa abordagem clínica tenha sido associada a benefícios no desfecho cardiovascular, recentemente tem sido questionada por estudos que mostram que a intensidade ou agressividade para remover fluidos durante a diálise intermitente está associada a estresse cardiovascular e dano potencial a órgãos.para remover fluidos durante a diálise intermitente está associada a estresse cardiovascular e dano potencial a órgãos. Uma abordagem mais precisa é necessária para melhorar o desfecho cardiovascular nessa população de alto risco. A avaliação e monitorização do estado hídrico baseiam-se em quatro componentes: avaliação clínica, ferramentas instrumentais não invasivas (por exemplo, US, bioimpedância, monitorização do volume sanguíneo), biomarcadores cardíacos (e.g. peptídeos natriuréticos), algoritmos e modelagem de sódio para estimar a transferência de massa. O manejo otimizado do desequilíbrio hídrico e de sódio em pacientes dialíticos consiste em ajustar a remoção de sal e líquido por diálise (ultrafiltração, dialisato de sódio), e restringir a ingestão de sal e o ganho de líquido entre as sessões de diálise. Tecnologia moderna que utiliza biosensores e ferramentas de controle de feedback, hoje parte da máquina de diálise, com análises sofisticadas, proporcionam o manejo direto sobre o sódio e a água de uma maneira mais precisa e personalizada. Prevê-se no futuro próximo que essas ferramentas poderão auxiliar na tomada de decisão do médico, com alto potencial para melhorar o resultado cardiovascular.
Asunto(s)
Humanos , Sodio/metabolismo , Diálisis Renal/efectos adversos , Hemodinámica/fisiología , Homeostasis/fisiología , Fallo Renal Crónico/terapia , Equilibrio Hidroelectrolítico/fisiología , Presión Sanguínea/fisiología , Algoritmos , Biomarcadores/metabolismo , Soluciones para Diálisis/química , Sistema Cardiovascular/fisiopatología , Diálisis Renal/normas , Resultado del Tratamiento , Descondicionamiento Cardiovascular , Nefrólogos/estadística & datos numéricos , Fallo Renal Crónico/fisiopatologíaRESUMEN
Fluid volume and hemodynamic management in hemodialysis patients is an essential component of dialysis adequacy. Restoring salt and water homeostasis in hemodialysis patients has been a permanent quest by nephrologists summarized by the 'dry weight' probing approach. Although this clinical approach has been associated with benefits on cardiovascular outcome, it is now challenged by recent studies showing that intensity or aggressiveness to remove fluid during intermittent dialysis is associated with cardiovascular stress and potential organ damage. A more precise approach is required to improve cardiovascular outcome in this high-risk population. Fluid status assessment and monitoring rely on four components: clinical assessment, non-invasive instrumental tools (e.g., US, bioimpedance, blood volume monitoring), cardiac biomarkers (e.g. natriuretic peptides), and algorithm and sodium modeling to estimate mass transfer. Optimal management of fluid and sodium imbalance in dialysis patients consist in adjusting salt and fluid removal by dialysis (ultrafiltration, dialysate sodium) and by restricting salt intake and fluid gain between dialysis sessions. Modern technology using biosensors and feedback control tools embarked on dialysis machine, with sophisticated analytics will provide direct handling of sodium and water in a more precise and personalized way. It is envisaged in the near future that these tools will support physician decision making with high potential of improving cardiovascular outcome.
Asunto(s)
Hemodinámica/fisiología , Homeostasis/fisiología , Fallo Renal Crónico/terapia , Diálisis Renal/efectos adversos , Sodio/metabolismo , Algoritmos , Biomarcadores/metabolismo , Presión Sanguínea/fisiología , Descondicionamiento Cardiovascular , Sistema Cardiovascular/fisiopatología , Soluciones para Diálisis/química , Humanos , Fallo Renal Crónico/fisiopatología , Nefrólogos/estadística & datos numéricos , Diálisis Renal/normas , Resultado del Tratamiento , Equilibrio Hidroelectrolítico/fisiologíaRESUMEN
BACKGROUND: Athletic cardiac remodeling can occasionally be difficult to differentiate from pathological hypertrophy. Detraining is a commonly used diagnostic test to identify physiological hypertrophy, which can be diagnosed if hypertrophy regresses. We aimed to establish whether athletic cardiac remodeling assessed by cardiovascular magnetic resonance is mediated by changes in intracellular or extracellular compartments and whether this occurs by 1 or 3 months of detraining. METHODS: Twenty-eight athletes about to embark on a period of forced detraining due to incidental limb bone fracture underwent clinical assessment, ECG, and contrast-enhanced cardiovascular magnetic resonance within a week of their injury and then 1 month and 3 months later. RESULTS: After 1 month of detraining, there was reduction in left ventricular (LV) mass (130±28 to 121±25 g; P<0.0001), increase in native T1 (1225±30 to 1239±30 ms; P=0.02), and extracellular volume fraction (24.5±2.3% to 26.0±2.6%; P=0.0007) with no further changes by 3 months. The decrease in LV mass was mediated by a decrease in intracellular compartment volume (94±22 to 85±19 mL; P<0.0001) with no significant change in the extracellular compartment volume. High LV mass index, low native T1, and low extracellular volume fraction at baseline were all predictive of regression in LV mass in the first month. CONCLUSIONS: Regression of athletic LV hypertrophy can be detected after just 1 month of complete detraining and is mediated by a decrease in the intracellular myocardial compartment with no change in the extracellular compartment. Further studies are needed in athletes with overt and pathological hypertrophy to establish whether native T1 and extracellular volume fraction may complement electrocardiography, echocardiography, cardiopulmonary exercise testing, and genetic testing in predicting the outcome of detraining.
Asunto(s)
Descondicionamiento Cardiovascular , Hipertrofia Ventricular Izquierda/diagnóstico por imagen , Hipertrofia Ventricular Izquierda/fisiopatología , Imagen por Resonancia Magnética/métodos , Remodelación Ventricular , Adaptación Fisiológica , Adolescente , Adulto , Atletas , Medios de Contraste , Electrocardiografía , Inglaterra , Femenino , Humanos , Masculino , Persona de Mediana Edad , Compuestos Organometálicos , Estudios ProspectivosRESUMEN
INTRODUCTION: Chronic dyspnoea that remains unexplained after resting pulmonary function and cardiovascular testing is a common problem in clinical practice. The aim of this study was to determine the utility of cardiopulmonary exercise testing (CPET) in the diagnosis of unexplained dyspnoea. METHODS: This retrospective single-centre study included consecutive patients with dyspnoea who had normal resting cardiopulmonary examinations (including chest X-ray, electrocardiography, pulmonary function tests [PFTs], and cardiac ultrasound). CPET was performed using a cycle ergometer with analysis of blood gases. The results were interpreted as being most likely due to one of the six pathophysiological mechanisms shown below. Consensus required agreement between at least three of the authors. RESULTS: Of the 194 patients included (median age 53 years, sex-ratio (M:F) 0.83, mean body mass index 27.3±5.36kg/m2), 32% of the test profiles were compatible with deconditioning, 20% with inappropriate hyperventilation (without gas exchange abnormalities), 18% with disorders of gas exchange, 13% with sub-maximal CPET, 9% with cardiovascular anomalies, and 8% with normal CPET. Of the patients with gas exchange abnormalities, the most common causes were bronchiectasis (6), emphysema (6), recent pneumonia (2), and diffuse interstitial pneumonitis (2). Ten of the patients with cardiovascular abnormalities had chronotropic insufficiencies, 5 had excessive tension responses, and 3 had disorders of rhythm or repolarisation. CONCLUSIONS: CPET may greatly facilitate the diagnosis of unexplained dyspnoea. More than 50% of the dyspnoea cases examined here were due to deconditioning or hyperventilation syndrome and would benefit from a simple pulmonary rehabilitation program.
Asunto(s)
Disnea/diagnóstico , Prueba de Esfuerzo/métodos , Adulto , Descondicionamiento Cardiovascular/fisiología , Disnea/etiología , Disnea/fisiopatología , Tolerancia al Ejercicio/fisiología , Femenino , Humanos , Hiperventilación/diagnóstico , Hiperventilación/etiología , Hiperventilación/fisiopatología , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pruebas de Función Respiratoria/métodos , Estudios RetrospectivosRESUMEN
BACKGROUND: Hospitalization is a profound contributor to functional loss for older adults. Many modifiable risk factors (ie, weakness) may persist after hospitalization, representing portents of poor health, re-hospitalization, or death. Older adults frequently receive home health (HH) care after hospitalization to manage functional deficits that have worsened during hospital stays. However, how best to manage these deficits in HH settings has yet to be determined. OBJECTIVE: The objective is to determine if a higher intensity, progressive, multi-component (PMC) intervention, initiated upon admission to HH after an acute hospitalization, improves objectively measured and self-reported physical function more than usual care (UC) physical therapy. DESIGN: This will be a 2-arm randomized controlled clinical trial. SETTING: The setting will be participant homes. PARTICIPANTS: A total of 200 older adults with deconditioning following acute hospitalization and referred for HH physical therapy will participate. INTERVENTION: Participants will be randomized to either a PMC treatment group or a UC group and receive 12 therapy visits over a 60-day period. PMC participants will perform lower extremity resistance training at 80% of a 1-repetition maximum, task-specific activities of daily living training, along with advanced gait and balance training. PMC groups will also receive nutritional supplementation and nursing support during transition from hospital to home. The UC group will receive standard of care HH interventions. MEASUREMENTS: Physical performance, self-reported function, fatigue, and health care utilization outcomes will be measured at baseline, 30 days, 60 days, 90 days, and 180 days. All measures will be assessed by blinded study personnel. LIMITATIONS: The limitation is an inability to blind treating therapists to study allocation. CONCLUSIONS: The authors hope to determine whether higher intensity, multi-component exercise interventions improve outcomes more than UC physical therapy for older adults recovering from acute hospitalization in HH settings.