Influência do tempo de internação hospitalar sobre a variabilidade da frequência cardíaca pediátrica por meio de método linear / Influence of hospital stay on the variability of pediatric heart rate by linear method / Influencia de la estancia hospitalaria en la variabilidad de la frecuencia cardiaca pediátrica por método lineal

INTRODUÇÃO: A imobilização prolongada acarreta prejuízos sistêmicos que repercute diretamente em maiores agravos aos pacientes, dentre eles se encontra a redução da VFC, indicativo de maior morbimortalidade clínica. OBJETIVO: Analisar se o tempo de internação hospitalar influencia a modulação autonômica da frequência cardíaca em pacientes pediátricos. METODOLOGIA: Estudo longitudinal, quantitativo e prospectivo, realizado em uma enfermaria pediátrica. A amostra foi de pacientes entre 4 a 11 anos, ambos gêneros, internados dentro das primeiras 48 horas. A coleta iniciou após a assinatura do TCLE pelo responsável, seguida do colhimento dos dados pessoais e clínicos dos pacientes seguida da coleta da VFC, repetida no último dia de internação. A captação da VFC foi realizada pelo monitor Polar RS800CX. Os dados foram transferidos e passados por uma análise matemática no programa Kubios HRV2.2. Por fim, os dados foram tabulados e analisados pelo Microsoft Excel 2013 e software BioEstat® 5.3 respectivamente. RESULTADOS: Os valores lineares no domínio do tempo obtiveram média pré (IRR=644,7 com P=0,42; RMSSD= 46,1 com P=0,017 e SDNN=43,5 com P=0,017) e pós (IRR=656,3; RMSSD=34,8; SDNN=35,38) e no domínio da frequência média pré (LF=41,9 com P=0,013; HF=58,0 com P=0,013; LF/HF=1,03 com P=0,04) e pós (LF=52,2; HF=47,7; LF/HF=3,56). A correlação de Pearson na análise tanto de RMSSD pós x tempo de internação, quanto SDNN pós x tempo de internação demonstraram R=0,55 e R=0,59 respectivamente. CONCLUSÃO: Foi observado que o tempo de internação exerce influência negativa sobre a modulação autonômica da frequência cardíaca em pacientes pediátricos.

INTRODUCTION: Prolonged immobilization causes systemic damage that has a direct impact on greater harm to patients, among which is the reduction in HRV, indicative of greater clinical morbidity and mortality. OBJECTIVE: To analyze whether the length of hospital stay influences the autonomic modulation of heart rate in pediatric patients. METHODOLOGY: Longitudinal, quantitative and prospective study, carried out in a pediatric ward. The sample consisted of patients between 4 and 11 years old, both genders, hospitalized within the first 48 hours. The collection began after the signature of the TCLE by the guardian, followed by the collection of the patients' personal and clinical data, followed by the HRV collection, repeated on the last day of hospitalization. HRV capture was performed by the Polar RS800CX monitor. The data were transferred and passed through a mathematical analysis in the Kubios HRV2.2 program. Finally, data were tabulated and analyzed using Microsoft Excel 2013 and BioEstat® 5.3 software, respectively. RESULTS: Linear values in the time domain obtained mean pre (IRR=644.7 with P=0.42; RMSSD=46.1 with P=0.017 and SDNN=43.5 with P=0.017) and post (IRR=656.3; RMSSD=34.8; SDNN=35.38) and in the pre mean frequency domain (LF=41.9 with P=0.013; HF=58.0 with P=0.013; LF/HF=1,03 with P=0.04) and powders (LF=52.2; HF=47.7; LF/HF=3.56). Pearson's correlation in the analysis of both the RMSSD post x length of stay and the SDNN post x length of stay showed R=0.55 and R=0.59 respectively. CONCLUSION: It was observed that the length of stay has a negative influence on the autonomic modulation of heart rate in pediatric patients.

INTRODUCCIÓN: La inmovilización prolongada provoca daños sistémicos que repercuten directamente en un mayor perjuicio para los pacientes, entre los que se encuentra la disminución de la VFC, indicativa de una mayor morbimortalidad clínica. OBJETIVO: Analizar si la duración de la estancia hospitalaria influye en la modulación autonómica de la frecuencia cardiaca en pacientes pediátricos. METODOLOGÍA: Estudio longitudinal, cuantitativo y prospectivo, realizado en una planta de pediatría. La muestra consistió en pacientes entre 4 y 11 años, de ambos sexos, hospitalizados dentro de las primeras 48 horas. La recogida se inició tras la firma del TCLE por el tutor, seguida de la recogida de los datos personales y clínicos de los pacientes, seguida de la recogida de la VFC, repetida el último día de hospitalización. La captura de la VFC se realizó con el monitor Polar RS800CX. Los datos se transfirieron y pasaron por un análisis matemático en el programa Kubios HRV2.2. Finalmente, los datos fueron tabulados y analizados utilizando Microsoft Excel 2013 y el software BioEstat® 5.3, respectivamente. RESULTADOS: Se obtuvieron valores lineales en el dominio temporal medios pre (TIR=644,7 con P=0,42; RMSSD=46,1 con P=0,017 y SDNN=43,5 con P=0,017) y post (TIR=656,3; RMSSD=34. 8; SDNN=35,38) y en el dominio de la frecuencia media pre (LF=41,9 con P=0,013; HF=58,0 con P=0,013; LF/HF=1,03 con P=0,04) y polvos (LF=52,2; HF=47,7; LF/HF=3,56). La correlación de Pearson en el análisis tanto de la RMSSD post x duración de la estancia como de la SDNN post x duración de la estancia mostró R=0,55 y R=0,59 respectivamente. CONCLUSIÓN: Se observó que la duración de la estancia influye negativamente en la modulación autonómica de la frecuencia cardíaca en pacientes pediátricos.

Neuro estímulo eléctrico periférico no invasivo como opción terapéutica en temblor esencial

El temblor esencial es el trastorno de movimiento más común en la actualidad, su prevalencia aumenta conforme lo hace la edad y se caracteriza principalmente por ser un temblor de acción de miembros superiores que puede llegar a afectar miembros inferiores, tronco y cabeza. Afecta directamente la calidad de vida de las personas al limitar las actividades del diario vivir llevando al desarrollo de trastornos como ansiedad y depresión. Objetivo. Describir los efectos adversos y la eficacia de los neuro estímulos periféricos no invasivos como opción terapéutica para el temblor esencial. Metodología. Se empleó la metodología de una revisión sistemática, basadas en las directrices PRISMA 2021 mediante la búsqueda de información en las siguientes bases de datos, PubMed, Scopus y Web of science. Además, se realizó una búsqueda especifica de todos los estudios centrados en la temática cuyo algoritmo de búsqueda se presenta a continuación, "terapia no invasiva" AND "temblor esencial" AND "neuroestimulación" AND "estimulación eléctrica transcutánea" en idioma español e inglés, entre los años 2017- 2022. Conclusión. La neuroestimulación eléctrica periférica no invasiva se presenta como una opción terapéutica prometedora en el tratamiento del temblor esencial. Los estudios han demostrado una mejora significativa en los síntomas del temblor en pacientes tratados con neuroestimulación eléctrica periférica no invasiva, lo que sugiere que este enfoque puede ser beneficioso para pacientes que no responden a otros tratamientos convencionales o que experimentan efectos secundarios adversos. Además, la neuroestimulación eléctrica periférica no invasiva es una técnica segura y bien tolerada por los pacientes.

Essential tremor is the most common movement disorder today, its prevalence increases with age and is characterized mainly as an action tremor of the upper limbs that can affect the lower limbs, trunk and head. It directly affects the quality of life of people by limiting the activities of daily living leading to the development of disorders such as anxiety and depression. Objective. To describe the adverse effects and efficacy of noninvasive peripheral neuro-stimuli as a therapeutic option for essential tremor. Methodology. The methodology of a systematic review was used, based on the PRISMA 2021 guidelines, by searching for information in the following databases: PubMed, Scopus and Web of science. In addition, a specific search was performed for all studies focused on the topic whose search algorithm is presented below, "noninvasive therapy" AND "essential tremor" AND "neurostimulation" AND "transcutaneous electrical stimulation" in Spanish and English language, between the years 2017- 2022. Conclusion. Noninvasive peripheral electrical neurostimulation is presented as a promising therapeutic option in the treatment of essential tremor. Studies have demonstrated significant improvement in tremor symptoms in patients treated with noninvasive peripheral electrical neurostimulation, suggesting that this approach may be beneficial for patients who do not respond to other conventional treatments or who experience adverse side effects. In addition, noninvasive peripheral electrical neurostimulation is a safe technique that is well tolerated by patients.

O tremor essencial é o distúrbio de movimento mais comum atualmente, sua prevalência aumenta com a idade e é caracterizado principalmente como um tremor de ação do membro superior que pode afetar os membros inferiores, o tronco e a cabeça. Ele afeta diretamente a qualidade de vida das pessoas ao limitar as atividades da vida diária, levando ao desenvolvimento de distúrbios como ansiedade e depressão. Objetivo. Descrever os efeitos adversos e a eficácia dos neuroestímulos periféricos não invasivos como opção terapêutica para o tremor essencial. Metodologia. Utilizamos a metodologia de uma revisão sistemática, com base nas diretrizes PRISMA 2021, buscando informações nos seguintes bancos de dados: PubMed, Scopus e Web of science. Além disso, foi realizada uma busca específica de todos os estudos focados no assunto cujo algoritmo de busca é apresentado a seguir, "terapia não invasiva" AND "tremor essencial" AND "neuroestimulação" AND "estimulação elétrica transcutânea" em espanhol e inglês, entre 2017 e 2022. Conclusão. A neuroestimulação elétrica periférica não invasiva é apresentada como uma opção terapêutica promissora no tratamento do tremor essencial. Estudos demonstraram melhora significativa nos sintomas do tremor em pacientes tratados com neuroestimulação elétrica periférica não invasiva, sugerindo que essa abordagem pode ser benéfica para pacientes que não respondem a outros tratamentos convencionais ou que apresentam efeitos colaterais adversos. Além disso, a estimulação elétrica nervosa periférica não invasiva é uma técnica segura e bem tolerada pelos pacientes.

The use of serial casting in the treatment of children with cerebral palsy: a study protocol

Introduction: Cerebral Palsy (CP) is characterized by a disorder of posture and movement, commonly leading to disabling orthopedic alterations, including muscle shortening, especially in the lower limbs. Stretching methods, performed gradually, are necessary to delay the impairment in function from muscle shortening. The use of serial casting aims to promote proper alignment, and an ideal and stable support base, in addition to better bone and joint health, leading to better posture, mobility, muscle function, and, subsequently, increased fitness and health.Objective: evaluate range of motion, postural control, and motor performance in children with CP, using serial casting, as well as to measure its effect on fitness through the autonomic nervous system (ANS).Methods: Sixty children and adolescents with CP, of both sexes, 3 to 12 years of age, will be divided into three groups: Groups A, B, and C, with 20 individuals each. Group A will use serial casting, Group B will use the orthosis continuously (with removal only allowed for bathing), and Group C will use the orthosis in their daily routine. Range of motion of the ankle of first and second resistance levels (R1 and R2), gross motor function measure (GMFM), and balance (measured by BERG scale) will be used in the initial and final assessments, and after 6 months and one year of follow-up. Timed-up-and-go (TUG), load distribution (baropodometry), motor performance measured through a real basketball game and the virtual MoveHero game, analysis of body angulation with "mydartfish", and cardiac autonomic modulation through heart rate variability will be assessed in three different situations: barefoot, with orthosis, and with casting.Conclusion: Serial casting demonstrates the potential to produce positive results in the treatment of individuals with CP regarding better alignment, with consequent motor and autonomic improvement.

Evaluation of comorbid diseases in obstructive sleep apnea syndrome

SUMMARY OBJECTIVE: It is known that obstructive sleep apnea syndrome affects many systems due to hypoxemia and hypercarbia. We aimed to demonstrate with the utilization of well-standardized questionnaire tools and electrophysiological tests that cognitive impairment, depression, autonomic dysfunction, and metabolic syndrome may occur in association with obstructive sleep apnea syndrome. METHODS: The electrophysiological examination protocol of autonomic nervous system functions was performed with sympathetic skin response and R-R Interval. Patients were administered Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index, Montreal Cognitive Assessment, and Hamilton Depression Rating Scale by physicians in face-to-face interviews. RESULTS: This study included 148 participants, consisting of 73 patients and 75 controls. There was a statistically significant difference between the patient group and control group with regard to sympathetic skin response, R-R Interval, post-hyperventilation R-R Interval, and R-R Interval variation (p<0.001). A statistically significant difference was observed between the patient group and control group in terms of median Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index, and Montreal Cognitive Assessment scores. It was observed that the control group achieved significantly better scores than the patient group in delayed recall (p<0.001) and language (p<0.05) categories. CONCLUSION: Obstructive sleep apnea syndrome patients should be screened for diseases, especially in the cardiovascular system, that cause serious morbidity and impair functionality such as dementia and depression. We believe that many comorbid diseases encountered in obstructive sleep apnea syndrome patients can be prevented with early diagnosis and continuous positive airway pressure treatment.

Is there a link between heart rate variability and cognitive decline? A cross-sectional study on patients with mild cognitive impairment and cognitively healthy controls / Existe uma ligação entre a variabilidade da frequência cardíaca e o declínio cognitivo? Um estudo transversal em pacientes com deficiência cognitiva leve e controles cognitivos saudáveis

Abstract Background Given that, up to date, there is no effective strategy to treat dementia, a timely start of interventions in a prodromal stage such as mild cognitive impairment (MCI) is considered an important option to lower the overall societal burden. Although autonomic functions have been related to cognitive performance, both aspects have rarely been studied simultaneously in MCI. Objective The aim of the present study was to investigate cardiac autonomic control in older adults with and without MCI. Methods Cardiac autonomic control was assessed by means of heart rate variability (HRV) at resting state and during cognitive tasks in 22 older adults with MCI and 29 healthy controls (HCs). Resting HRV measurement was performed for 5 minutes during a sitting position. Afterwards, participants performed three PC-based tasks to probe performance in executive functions and language abilities (i.e., Stroop, N-back, and a verbal fluency task). Results Participants with MCI showed a significant reduction of HRV in the frequency-domain (high frequency power) and nonlinear indices (SD2, D2, and DFA1) during resting state compared to HCs. Older individuals with MCI exhibited decreases in RMSSD and increases in DFA1 from resting state to Stroop and N-back tasks, reflecting strong vagal withdrawal, while this parameter remained stable in HCs. Conclusion The results support the presence of autonomic dysfunction at the early stage of cognitive impairment. Heart rate variability could help in the prediction of cognitive decline as a noninvasive biomarker or as a tool to monitor the effectiveness of therapy and prevention of neurodegenerative diseases.

Resumo Antecedentes Como não existe até o momento uma estratégia eficaz para tratar a demência de comprometimento cognitivo leve (MCI, na sigla em inglês), as intervenções em um estágio prodrômico são consideradas uma opção. Embora as funções autonômicas tenham sido relacionadas ao desempenho cognitivo, ambos os aspectos raramente foram estudados simultaneamente no MCI. Objetivo Investigar o controle autonômico cardíaco em idosos com e sem MCI. Métodos O controle autonômico cardíaco foi avaliado por meio da variabilidade da frequência cardíaca (HRV, na sigla em inglês) em repouso e durante tarefas cognitivas, em 22 idosos com MCI e 29 controles saudáveis (HCs, na sigla em inglês). A medida da HRV de repouso foi realizada por 5 minutos na posição sentada. Os participantes realizaram três tarefas executadas em computador para testar o desempenho em funções executivas e habilidades de linguagem (o teste de cores e palavras - Stroop, Tarefa N-back auditiva e uma tarefa de fluência verbal). Resultados Em pacientes com MCI, observou-se uma redução significativa da HRV no domínio da frequência (potência de alta frequência) e índices não lineares (SD2, D2 e DFA1) durante o estado de repouso em comparação com os HCs. Indivíduos mais velhos com MCI exibiram diminuições em RMSSD e aumentos em DFA1 do estado de repouso para Stroop e tarefas N-back, refletindo forte recessão vagal, enquanto este parâmetro permaneceu estável em HC. Conclusão Observou-se disfunção autonômica na fase inicial da neurodegeneração. A HRV pode ajudar na previsão do declínio cognitivo, como um biomarcador não invasivo, ou como uma ferramenta para monitorar a eficácia da terapia e prevenção de doenças neurodegenerativas.

Autonomic heart rate modulation in patients with coronavirus disease 2019 in mechanical ventilation

SUMMARY BACKGROUND: Patients with coronavirus disease 2019 on automatic mechanical ventilation have greater heart rate modulation with greater parasympathetic modulation. OBJECTIVE: To analyze the autonomic modulation of heart rate in critically ill patients with coronavirus disease 2019 on invasive mechanical ventilation. METHODS: A cross-section study was carried out with 36 individuals divided into two groups. The control group included patients of both genders, in orotracheal intubation with invasive mechanical ventilation under controlled assisted mode, hospitalized in the intensive care unit for another 24 h. In the non-COVID group, patients diagnosed with coronavirus disease 2019 in the same condition mentioned in the control group. RESULTS: There was a significant increase in heart rate variability (standard deviation of all normal RR intervals recorded at an interval of time; p=0.001; triangular interpolation histogram of RR intervals; p=0.048; and SD2; p=0.014) in the coronavirus disease group compared to the non-COVID group. Successively, the parameters that demonstrate parasympathetic modulation are shown to be higher in the group of patients with coronavirus disease 2019 (root mean square of the square of differences between adjacent normal RR intervals in an interval of time; p<0.001; pNN50; p<0.001; SD1; p=0.002; and high frequency; p=0.022). CONCLUSIONS: There was a greater autonomic modulation of heart rate with a greater parasympathetic modulation in patients with coronavirus disease 2019 on mechanical ventilation.

Neurological symptoms and comorbidity profile of hospitalized patients with COVID-19 / Sintomas neurológicos e perfil de comorbidades de pacientes hospitalizados com COVID-19

Abstract Background The neurological manifestations in COVID-19 adversely impact acute illness and post-disease quality of life. Limited data exist regarding the association of neurological symptoms and comorbid individuals. Objective To assess neurological symptoms in hospitalized patients with acute COVID-19 and multicomorbidities. Methods Between June 2020 and July 2020, inpatients aged 18 or older, with laboratory-confirmed COVID-19, admitted to the Hospital São Paulo (Federal University of São Paulo), a tertiary referral center for high complexity cases, were questioned about neurological symptoms. The Composite Autonomic Symptom Score 31 (COMPASS-31) questionnaire was used. The data were analyzed as a whole and whether subjective olfactory dysfunction was present or not. Results The mean age of the sample was 55 ± 15.12 years, and 58 patients were male. The neurological symptoms were mostly xerostomia (71%), ageusia/hypogeusia (50%), orthostatic intolerance (49%), anosmia/hyposmia (44%), myalgia (31%), dizziness (24%), xerophthalmia (20%), impaired consciousness (18%), and headache (16%). Furthermore, 91% of the patients had a premorbidity. The 44 patients with subjective olfactory dysfunction were more likely to have hypertension, diabetes, weakness, shortness of breath, ageusia/hypogeusia, dizziness, orthostatic intolerance, and xerophthalmia. The COMPASS-31 score was higher than that of previously published controls (14.85 ± 12.06 vs. 8.9 ± 8.7). The frequency of orthostatic intolerance was 49% in sample and 63.6% in those with subjective olfactory dysfunction (2.9-fold higher risk compared to those without). Conclusion A total of 80% of inpatients with multimorbidity and acute COVID-19 had neurological symptoms. Chemical sense and autonomic symptoms stood out. Orthostatic intolerance occurred in around two-thirds of the patients with anosmia/hyposmia. Hypertension and diabetes were common, mainly in those with anosmia/hyposmia.

Resumo Antecedentes As manifestações neurológicas na COVID-19 impactam adversamente na enfermidade aguda e na qualidade de vida após a doença. Dados limitados existem em relação a associação de sintomas neurológicos e indivíduos com comorbidades. Objetivo Avaliar os sintomas neurológicos em pacientes de hospitalizados com COVID-19 aguda e múltiplas comorbidades. Métodos Entre junho e julho de 2020, pacientes de hospitais com idade 18 anos ou acima e COVID-19 laboratorialmente confirmada, admitidos no Hospital São Paulo (Universidade Federal de São Paulo), um centro de referência terciário para casos de alta complexidade, foram perguntados sobre sintomas neurológicos. O questionário Pontuação composta de sintoma autonômico (COMPASS-31) foi usado. Os dados foram analisados no geral e se a disfunção olfatória subjetiva estava presente ou não. Resultados A média de idade da amostra foi 55 ± 15.12 anos. 58 pacientes eram homens. Os sintomas neurológicos foram principalmente xerostomia (71%), ageusia/hipogeusia (50%), intolerância ortostática (49%), anosmia/hiposmia (44%), mialgia (31%), tontura (24%), xeroftalmia (20%), comprometimento na consciência (18%) e cefaleia (16%). Além disso, 91 % dos pacientes tinham uma pré-morbidade. Os 44 pacientes com disfunção olfatória tinham maior chance de ter hipertensão, diabetes, fraqueza, falta de ar, ageusia/hipogeusia, tontura, intolerância ortostática e xeroftalmia. A pontuação do COMPASS-31 foi maior do que a de controles previamente publicados (14,85 ± 12,06 vs. 8,9 ± 8,7). A frequência de intolerância ortostática foi 49% na amostra e 63,6% naqueles com disfunção olfatória subjetiva (risco 2.9 vezes maior comparado com os sem). Conclusão Um total de 80% dos pacientes hospitalizados com múltiplas morbidades e COVID-19 aguda tinham sintomas neurológicos. Os sintomas do sentido químico e autonômicos se destacaram. A intolerância ortostática ocorreu em cerca de dois terços dos pacientes com anosmia/hiposmia. A hipertensão e o diabetes foram comuns, principalmente naqueles com anosmia/hiposmia.

Melhora da Pressão Arterial após Jejum Intermitente na Hipertensão: O Sistema Renina-Angiotensina e o Sistema Nervoso Autônomo Podem Funcionar? / Improvement in Blood Pressure After Intermittent Fasting in Hipertension: Could Renin-Angiotensin System and Autonomic Nervous System Have a Role?

Resumo Fundamento Embora tenha sido relatado que a dieta de jejum intermitente (JI) tem efeitos positivos na saúde do coração e na melhora da pressão arterial, ainda não foi suficientemente esclarecido como poderia ter esses efeitos positivos.Objetivo: Nosso objetivo foi avaliar os efeitos do JI no sistema nervoso autônomo (SNA) e no sistema renina-angiotensina (SRA), que estão intimamente relacionados à pressão arterial. Métodos Setenta e dois pacientes hipertensos foram incluídos no estudo, e os dados de 58 pacientes foram usados. Todos os participantes jejuaram por cerca de 15-16 horas por 30 dias. Os participantes foram avaliados com monitorização ambulatorial da pressão arterial de 24 horas e eletrocardiograma Holter antes e após o JI; também, amostras de sangue venoso de 5 ml foram coletadas para avaliação dos níveis séricos de angiotensina I (Ang-I) e angiotensina II (Ang-II) e da atividade da enzima conversora de angiotensina (ECA). Para análise dos dados, o valor de p < 0,05 foi aceito como significativo. Resultados Comparado ao pré-JI, observou-se queda significativa nas pressões arteriais dos pacientes no pós-JI. Um aumento na potência de alta frequência (AF) e na raiz quadrada média da soma dos quadrados das diferenças entre intervalos NN adjacentes (RMSSD) foram observados após o protocolo JI (p=0,039, p=0,043). A Ang-II e a atividade da ECA foram menores em pacientes após JI (p=0,034, p=0,004), e níveis decrescentes de Ang-II foram determinados como fatores preditivos para melhora da pressão arterial, como o aumento da potência de AF e RMSSD. Conclusão Os presentes achados de nosso estudo demonstraram uma melhora na pressão arterial e a relação da pressão arterial com resultados positivos, incluindo VFC, atividade da ECA e níveis de Ang-II após o protocolo JI.

Abstract Background Although it has been reported that the intermittent fasting (IF) diet has positive effects on heart health and improvement in blood pressure, it has not been sufficiently clarified how it could have these positive effects yet. Objective We aimed to evaluate the effects of IF on the autonomic nervous system (ANS) and renin-angiotensin system (RAS), which are closely related to blood pressure. Methods Seventy-two hypertensive patients were included in the study, and the data of 58 patients were used. All the participants fasted for about 15-16 hours for 30 days. Participants were evaluated with 24-hour ambulatory blood pressure monitoring and Holter electrocardiography before and after IF; also, 5 ml venous blood samples were taken for assessment of Serum angiotensin I (Ang-I) and angiotensin II (Ang-II) levels and angiotensin-converting enzyme (ACE) activity. For data analysis, the p-value <0.05 was accepted as significant. Results Compared to pre-IF, a significant decrease was observed in the patients' blood pressures in post-IF. An increase in high-frequency (HF) power and the mean root square of the sum of squares of differences between adjacent NN intervals (RMSSD) were observed after the IF protocol (p=0.039, p=0.043). Ang-II and ACE activity were lower in patients after IF (p=0.034, p=0.004), and decreasing Ang-II levels were determined as predictive factors for improvement of the blood pressure, like the increase in HF power and RMSSD. Conclusion The present findings of our study demonstrated an improvement in blood pressure and the relationship of blood pressure with positive outcomes, including HRV, ACE activity, and Ang-II levels after the IF protocol.

Autonomic dysfunction in COVID-19 patients receiving mechanical ventilation: A cross-sectional study

ABSTRACT BACKGROUND: Coronavirus disease 2019 (COVID-19) can damage cardiac tissue by increasing troponin levels and inducing arrhythmias, myocarditis, and acute coronary syndrome. OBJECTIVES: To analyze the impact of COVID-19 on cardiac autonomic control in mechanically ventilated intensive care unit (ICU) patients. DESIGN AND SETTING: This cross-sectional analytical study of ICU patients of both sexes receiving mechanical ventilation was conducted in a tertiary hospital. METHODS: Patients were divided into COVID-19-positive (COVID(+)) and COVID-19-negative (COVID(-)) groups. Clinical data were collected and heart rate variability (HRV) records obtained using a heart rate monitor. RESULTS: The study sample comprised 82 subjects: 36 (44%) in the COVID(-) group (58.3% female; median age, 64.5 years) and 46 (56%) in the COVID(+) group (39.1% females; median age, 57.5 years). The HRV indices were lower than the reference values. An intergroup comparison identified no statistically significant differences in the mean normal-to-normal (NN) interval, standard deviation of the NN interval, or root mean square of successive differences in NN intervals. The COVID(+) group had an increased low frequency (P = 0.05), reduced high frequency (P = 0.045), and increased low frequency/high frequency (LF/HF) ratio (P = 0.048). There was a weak positive correlation between LF/HF and length of stay in the COVID(+) group. CONCLUSION: Patients who received mechanical ventilation had lower overall HRV indices. COVID(+) patients who received mechanical ventilation had lower vagal HRV components. These findings likely indicate clinical applicability, as autonomic control impairments are associated with a greater risk of cardiac death.

Association of coronary artery calcium with heart rate variability in the Brazilian Longitudinal Study of Adult Health - ELSA-Brasil

Current data shows that the autonomic and vascular systems can influence each other. However, only a few studies have addressed this association in the general population. We aimed to investigate whether heart rate variability (HRV) was associated with coronary artery calcium (CAC) in a cross-sectional analysis of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). We examined baseline data from 3138 participants (aged 35 to 74 years) without previous cardiovascular disease who underwent CAC score assessment and had validated HRV recordings. Prevalent CAC was defined as a CAC score>0, and HRV analyses were performed over 5-min segments. We detected CAC score>0 in 765 (24.4%) participants. Subgroup analyses in older participants (≥49 years) adjusted for sociodemographic and clinical variables revealed that CAC score>0 was associated with lower values of standard deviation of NN intervals (SDNN) (odds ratio [OR]=1.32; 95%CI: 1.05,1.65), root mean square of successive differences between adjacent NN intervals (RMSSD) (OR=1.28; 95%CI: 1.02,1.61), and low frequency (LF) (OR=1.53, 95%CI: 1.21,1.92). Interaction analysis between HRV indices and sex in age-stratified groups revealed significant effect modification: women showed increased OR for prevalent CAC in the younger group, while for men, the associations were in the older group. In conclusion, participants aged ≥49 years with low SDNN, RMSSD, and LF values were more likely to present prevalent CAC, suggesting a complex interaction between these markers in the pathogenesis of atherosclerosis. Furthermore, our results suggested that the relationship between CAC and HRV might be sex- and age-related.

Immediate effect of an orthostatic device in amputees who practice physical activity / Efecto inmediato de un dispositivo ortostático en amputados que practican actividad física / Efeito imediato de um dispositivo ortostático em amputados praticantes de atividade física

ABSTRACT Introduction: Lower limb amputation affects mainly economically active young adults, causing great socio-economic impact due to impaired work capacity, socialization, and quality of life. Thus, the use of orthostatic devices could make reintegration of the individual back into the work environment possible. Objective: To evaluate the immediate effect of using a postural elevation device on physiological parameters and plantar pressure levels in amputees who practice physical activity. Methods: Sociodemographic and perceived sleep quality data were collected from 14 adults of both sexes with lower limb amputations, who practice physical activity. The participants were placed in postural elevation equipment for a period of 90 minutes with monitoring of physiological parameters such as blood pressure, heart rate, and oxygen saturation. Parameters related to the autonomic nervous system and plantar pressure levels were also evaluated. Data were also collected during recovery at 15- and 30-minute intervals after using the device. Data analysis was performed using two-way ANOVA or a mixed-effects model with Sidak's multiple comparisons test. Results: For all cardiovascular parameters (p>0.05) analyzed, the activation level of the autonomic nervous system (p>0.05), and plantar pressure (p>0.05), no evidence of differences was observed during use of the orthostatic device in all evaluated periods. Conclusion: The use of postural elevation equipment for 90 minutes does not generate, as an immediate effect, changes in physiological parameters and postural control in amputees who practice physical activity. Level of evidence II; Therapeutic studies - investigation of treatment results. Clinical relevance statement .

RESUMEN Introducción: La amputación de miembros inferiores afecta mayoritariamente a jóvenes adultos económicamente activos, lo que provoca un gran impacto socioeconómico debido al compromiso de la capacidad laboral, la socialización y la calidad de vida. Así, el uso de dispositivos ortostáticos permitiría la reinserción del individuo en el entorno laboral. Objetivo: Evaluar el efecto inmediato del uso de un dispositivo de elevación postural en los parámetros fisiológicos y en los niveles de presión plantar de amputados que practican actividad física. Métodos: Se recogieron datos sociodemográficos y la percepción de la calidad del sueño de 14 adultos de ambos sexos con amputaciones de miembros inferiores, practicantes de actividad física. Los participantes fueron colocados en equipos de elevación postural durante 90 minutos con monitoreo de parámetros fisiológicos como presión arterial, frecuencia cardíaca, saturación y sistema nervioso autónomo, además de los niveles de presión plantar. También se recopilaron datos durante la recuperación a intervalos de 15 y 30 minutos después de usar el dispositivo. El análisis de datos se realizó mediante ANOVA two-way o un modelo de efectos mixtos con la prueba de comparaciones múltiples de Sidak, p < 0,05. Resultados: Para todos los parámetros cardiovasculares (p> 0,05) analizados, el nivel de activación del sistema nervioso autónomo (p> 0,05) y la presión plantar (p> 0,05), no se observaron diferencias a lo largo del uso del dispositivo ortostático en todos los períodos evaluados. Conclusión: El uso del equipo de elevación postural durante 90 minutos no genera, como efecto inmediato, cambios en los parámetros fisiológicos y en el control postural de los amputados que practican actividades físicas. Nivel de evidencia II; Estudios terapéuticos: investigación de los resultados de los tratamientos. Declaración de relevancia clínica .

RESUMO Introdução: A amputação de membros inferiores afeta em sua maioria adultos jovens economicamente ativos, o que ocasiona grande impacto socioeconômico devido ao comprometimento da capacidade laboral, socialização e qualidade de vida. Desta forma, as utilizações de dispositivos ortostáticos possibilitariam a reinserção do indivíduo no ambiente de trabalho. Objetivo: Avaliar o efeito imediato da utilização de um dispositivo de elevação postural nos parâmetros fisiológicos e nos níveis da pressão plantar de amputados praticantes de atividade física. Métodos: Foram coletados os dados sociodemográficos e a percepção da qualidade do sono de 14 adultos de ambos os sexos com amputações de membro inferior que praticam atividade física. Os participantes foram colocados em um equipamento de elevação postural durante 90 minutos com monitorização dos parâmetros fisiológicos como pressão arterial, frequência cardíaca, saturação e sistema nervoso autônomo, além dos níveis da pressão plantar. Os dados também foram coletados durante a recuperação (15 e 30 minutos depois do uso do dispositivo). A análise dos dados foi realizada pela ANOVA two-way ou modelo de efeitos mistos com teste de comparações múltiplas de Sidak, p < 0,05. Resultados: Para todos os parâmetros cardiovasculares (p > 0,05) analisados, nível de ativação sistema nervoso autônomo (p > 0,05) e pressão plantar (p > 0,05) não foram observadas diferenças ao longo do uso do dispositivo ortostático em todos os períodos avaliados. Conclusão: A utilização do equipamento de elevação postural por 90 minutos não gera como efeito imediato, alterações nos parâmetros fisiológicos e no controle postural de amputados praticantes de atividade física. Nível de evidência II; Estudos terapêuticos: investigação dos resultados dos tratamentos Declaração de relevância clínica.

Fenotipo motor y disautonomía cardiovascular de pacientes con enfermedad de Parkinson en la consulta de neurología de un hospital en Táchira (Venezuela) / Motor phenotype and cardiovascular dysautonomia in patients with Parkinson's disease from a neurology outpatient clinic in Táchira (Venezuela)

RESUMEN INTRODUCCIÓN: La enfermedad de Parkinson es un trastorno neurodegenerativo frecuente que se caracteriza por manifestaciones de tipo motor y no motor, tales como disautonomía, trastornos del sueño, disfunción sexual, alteraciones psiquiátricas y cognitivas, entre otros. Según su fenotipo motor, se puede clasificada en tremórica dominante (TD), dificultad para la marcha/inestabilidad postural (DMI) y un fenotipo indeterminado. En el estudio se determina la influencia del fenotipo motor en la disautonomía cardiovascular del paciente con Parkinson en los pacientes de la consulta de neurología del hospital del IVSS "Dr. Patrocinio Peñuela Ruiz" entre mayo del 2015 y abril del 2016. METODOS: Estudio observacional, descriptivo, transversal en pacientes mayores de 40 años con EP idiopática. Se evaluó el MDS-UPDRS, Hoehn y Yahr, Scopa-AUT , Hipotensión Ortostática y Rines-Valcardi. RESULTADOS: Se obtuvo una muestra de 57 pacientes; luego de la aplicación de los criterios de inclusión y exclusión se estudiaron 37 sujetos. Todos los pacientes tuvieron algún grado de disautonomía (medida con la escala Scopa-AUT). El Scopa-AUT fue mayor en los pacientes con hipotensión ortostática (p = ,003), observándose igual diferencia para la subescala cardiovascular (p = ,026). Se observó que la neuropatía autonómica (medida con Rines-Valcardi) fue más frecuente en aquellos pacientes con fenotipo DMI (p = < ,001), y que la hipotensión ortostática fue también más frecuente en aquellos pacientes con dicho fenotipo (DMI) (p = ,016). CONCLUSIÓN: La presencia de disautonomía es frecuente en los pacientes con EP; hubo diferencias en la puntuación total y la subescala cardiovascular del Scopa-AUT, de acuerdo CON la presencia de hipotensión ortostática; aquellos sujetos que cursan con fenotipo motor DMI tienen mayor riesgo de presentar hipotensión ortostática y neuropatía autonómica cardíaca.

ABSTRACT INTRODUCTION: Parkinson's disease is a frequent neurodegenerative disorder characterized by motor and non-motor manifestations, such as dysautonomia, sleep disorders, sexual dysfunction, and psychiatric and cognitive disorders. It can be classified according to their motor phenotype in tremor-dominant (TD), postural instability/gait difficulty (DMI), and indeterminate subtypes. This study established the influence of motor phenotype on the cardiovascular dysautonomia of patients with Parkinson's disease from the neurology outpatient clinic at the IVSS hospital "Dr. Patrocinio Peñuela Ruiz," from May 2015 to April 2016. METHODS: Observational, descriptive, cross-sectional study in patients older than 40 years with idiopathic PD. The MDS-UPDRS scale, Hoehn and Yahr scale, Scopa-AUT scale, Orthostatic Hypotension, and RINES-VALCARDI were evaluated. RESULTS: A sample of 57 was obtained, and after applying inclusion and exclusion criteria, 37 subjects were studied. All the patients had some degree of dysautonomia (measured with SCOPA- AUT scale). The SCOPA-AUT was higher in patients with orthostatic hypotension (p= .003), finding this same difference for the cardiovascular subscale (p = .026). Both autonomic neuropathy (measured with RINES-VALCARDI) and orthostatic hypotension were found more frequently on the DMI phenotype (p= <.001 and p=.016). CONCLUSION: Dysautonomia is frequent in PD patients; there was a difference between SCOPA-AUT total score and cardiovascular subscale according to orthostatic hypotension; those with DMI phenotype have a greater risk of orthostatic hypotension and cardiac autonomic neuropathy.

Comparison of time domain heart rate variability parameters between smokers and non-smokers

Background: Cigarette smoking induced sympathetic overdrive is one of the major independent modifiable risk factors for cardiovascular mortality and morbidity. There is altered autonomic activity with increased adrenergic activity in chronic smoking which also predisposes to cardiovascular morbidity and mortality. There are several tests that can determine the Autonomic Activity. Among them, heart rate variability (HRV), especially the time domain parameters of it, is simple, easy to perform, and non-invasive test for diagnosing autonomic dysfunction in the smokers. Aims and Objectives: The aims of this study were to compare the time domain parameters of HRV in smokers and non-smokers. Materials and Methods: The present study was carried out at autonomic function laboratory and cardiovascular function laboratory, Department of Physiology, Government Medical College, Bhavnagar, among 200 subjects, out of which 100 were smokers and 100 were non-smokers, in age group of 20–50 years. Results: There was a significant increase in mean heart rate, blood pressure, and R-R interval in smokers as compared to the non-smokers. There was also a significant decrease in all time domain parameters of HRV which suggests profound sympathetic overdrive and a decrease in vagal tone due to the actions of nicotine presents in tobacco smoke. Conclusions: Cigarette smoking plays a major role in degradation and decreased function of autonomic nervous system.

Asymptomatic course of overt primary hypothyroidism with a very high peak systolic velocity of the superior thyroid arteries: A case report

This study reports the case of a 59-year-old woman with asymptomatic overt hypothyroidism who presented with signs of increased thyroid exertion involving the autonomic nervous system. These signs included significantly increased peak systolic velocity (PSV) of the superior thyroid arteries (STA) and moderately increased blood flow intensity. The findings suggest an increase in the rate of thyroxine deiodination and the sufficiency of free triiodothyronine (FT3) for the functional needs of the body. The absence of typical symptoms of hypothyroidism may depend on the sufficiency of FT3 in the serum and additional nonhormonal circumstances. Hence, FT3 should always be measured in addition to thyroid-stimulating hormone and free thyroxine levels. When Doppler ultrasound is used, the intensity of blood flow and PSV-STA from both sides should be determined to assess the magnitude of thyroid exertion. Probably, PSV-STA may not be an absolute criterion for the diagnosis of Graves� disease

Efeitos Agudos da Bebida Energética sobre Parâmetros Autonômicos e Cardiovasculares em Indivíduos com Diferentes Capacidades Cardiorrespiratórias: Um Ensaio Controlado, Randomizado, Crossover e Duplo Cego / Acute Effects of Energy Drink on Autonomic and Cardiovascular Parameters Recovery in Individuals with Different Cardiorespiratory Fitness: A Randomized, Crossover, Double-Blind and Placebo-Controlled Trial

Resumo Fundamento Tem-se sugerido que o consumo de bebidas energéticas (BEs) possa afetar a atividade cardiovascular. Objetivos Investigar os efeitos agudos da ingestão de BE sobre a variabilidade da frequência cardíaca (VFC) recuperação cardiovascular após exercício aeróbico moderado em homens de diferentes capacidades cardiorrespiratórias. Métodos Este é um estudo randomizado, duplo cego, crossover, controlado por placebo. Vinte e oito jovens adultos foram divididos em dois grupos de acordo com o pico de consumo de oxigênio (pico de VO2): (1) pico de VO2 alto (AO) - pico de VO2 > 52,15 mL/Kg/min, e (2) pico de VO2 baixo (BO) - pico de VO2 <52,15 mL/Kg/min. Os indivíduos de ambos os grupos foram submetidos a dois protocolos de exercícios em ordem aleatória: exercício moderado aeróbico (60% de pico de VO2) após a ingestão de 250 mL de água (protocolo placebo) ou 250 mL de BE (protocolo BE). Durante os testes de exercício, foram registrados valores de parâmetros cardiorrespiratórios e de VFC. Resultados Foram observadas diferenças significativas para o índice de LF (unidades normalizadas) entre "repouso" e "Rec1" nos grupos de AO e BO durante o protocolo BE. Para a razão LF/HF, foram observadas diferenças significativas entre "repouso" e Rec1 nos grupos AO e BO nos protocolos BE. Conclusão A ingestão aguda de BE retardou a recuperação da frequência cardíaca após o exercício em indivíduos com capacidade cardiorrespiratória baixa e indivíduos com capacidade cardiorrespiratória alta.

Abstract Background It has been suggested that the consumption of energy drinks (ED) may affect cardiovascular activity. Objectives to investigate the acute effects of ED intake on heart rate variability (HRV) and cardiovascular recovery after moderate aerobic exercise in males with different cardiorespiratory capacities. Methods This is a randomized, double-blind, crossover, placebo-controlled study. Twenty-eight young adults were split into two groups according to their peak oxygen consumption (VO2peak) values: (1) High VO2 peak (HO) - VO2 peak > 52.15 mL/kg/min, and (2) low VO2 peak (LO) - peak VO2 <52.15 mL/kg/min. Subjects of both groups underwent two exercise protocols in randomized order: moderate aerobic exercise (60% of VO2peak) following the intake of 250 mL of water (placebo protocol) or 250 mL of ED (ED protocol). During the exercise tests, values of cardiorespiratory and HRV parameters were recorded. Results Significant differences were observed for the LF (normalized units) index between rest and Rec1 in HO energy and LO groups during the ED protocol. For the LF/HF ratio, significant differences were seen between rest and Rec1 in HO and LO during ED protocols. Conclusion Acute ED intake delayed heart rate recovery after exercise in subjects with low and high cardiorespiratory fitness.

Autonomic response of older women to the submaximal effort in the six-minute walk test: a cross-sectional study / Resposta autonômica de mulheres idosas ao esforço submáximo do teste de caminhada de seis minutos: um estudo transversal / Respuesta autonómica de ancianas al esfuerzo submáximo en la prueba de paso de seis minutos: un estudio transversal

ABSTRACT This cross-sectional study aimed to evaluate the autonomic response of older women in the six-minute walk test. In total, 32 women aged 60 years or older without a diagnosed health problem were evaluated during the six-minute walk test. To monitor the autonomic response, the following variables were considered: heart rate, systolic and diastolic blood pressure, respiratory rate, and perceived exertion. These variables were compared during rest, effort, and recovery. This study also sought a correlation between autonomic function variables and performance in the test and perceived exertion. Results showed that the effort made by older women in the six-minute walk test induces an autonomic response resulting in increased heart rate and systolic and diastolic blood pressure; however, the respiratory rate remained unchanged during the test. Diastolic blood pressure remained high during recovery. No correlation was found neither between perceived exertion and cardiovascular physiological response nor between distance covered and variation of the autonomic response or level of physical conditioning. Therefore, the effort spent in the six-minute walk test promotes an autonomic response in older women, increasing cardiovascular stress without increasing ventilation. In this context, the Borg scale was not representative of cardiovascular stress during the test.

RESUMO O objetivo deste estudo foi investigar a resposta autonômica de idosas ao esforço do teste de caminhada de 6 minutos (TC6M). Realizou-se um estudo transversal a partir da avaliação de 32 idosas, sem problemas de saúde diagnosticados, com 60 anos ou mais, durante o TC6M. Para o monitoramento da resposta autonômica, foram consideradas as seguintes variáveis: frequência cardíaca, pressão arterial sistólica e diastólica, frequência respiratória e percepção de esforço. Essas variáveis foram comparadas durante o período de repouso, esforço e recuperação. Buscou-se também correlação entre as variáveis da função autonômica e o desempenho no teste e a percepção de esforço. Os resultados demonstraram que o esforço gerado no TC6M induz uma resposta autonômica que leva ao aumento da frequência cardíaca e da pressão arterial sistólica e diastólica em mulheres, porém a frequência respiratória permaneceu inalterada durante o teste. A pressão arterial diastólica permaneceu elevada durante a recuperação. Não houve correlação entre a percepção de esforço e a resposta fisiológica cardiovascular apresentada, nem entre a distância percorrida e a variação da resposta autonômica ou o nível de condicionamento físico. Concluiu-se que o esforço despendido no TC6M promove uma resposta autonômica em idosas, intensificando o estresse cardiovascular sem aumentar a ventilação. Nesse contexto, a escala de Borg não foi representativa do estresse cardiovascular durante o teste.

RESUMEN El objetivo de este estudio fue investigar la respuesta autonómica de ancianas al esfuerzo en la prueba de paso de 6 minutos (6MWT). Se realizó un estudio transversal con la participación de 32 ancianas, de 60 años o más, sin problemas de salud diagnosticados durante la 6MWT. Para monitorear la respuesta autonómica, se consideraron las siguientes variables: frecuencia cardíaca, presión arterial sistólica y diastólica, frecuencia respiratoria y esfuerzo percibido. Se compararon estas variables durante el período de reposo, esfuerzo y recuperación. También se buscó una correlación entre las variables de función autonómica y rendimiento en la prueba y el esfuerzo percibido. Los resultados mostraron que el esfuerzo producido en la 6MWT genera una respuesta autonómica que conduce a un aumento de la frecuencia cardíaca y de la presión arterial sistólica y diastólica en las mujeres, pero la frecuencia respiratoria se mantuvo sin cambios durante la prueba. La presión arterial diastólica se mantuvo alta durante el período de recuperación. No hubo correlación entre el esfuerzo percibido y la respuesta fisiológica cardiovascular presentada, tampoco entre la distancia recorrida y la variación de la respuesta autonómica o el nivel de condicionamiento físico. Se concluyó que el esfuerzo realizado en la 6MWT generó una respuesta autonómica en las ancianas al intensificar el estrés cardiovascular pero sin aumentar la ventilación. En este contexto, la escala de Borg no fue significativa para el estrés cardiovascular durante la prueba.

Nível de Atividade Física, Força de Preensão Palmar e Variabilidade da Frequência Cardíaca em Idosos / Physical activity level, grip strength and heart rate variability in elderly

Introdução: O processo de envelhecimento ocasiona alterações no sistema cardiovascular e afeta a capacidade funcional. Objetivo: Analisar as associações entre indicadores sociodemográficos, índice de massa corporal (IMC), comorbidades, nível de atividade física (NAF) e força de preensão palmar (FPP) na variabilidade da frequência cardíaca (VFC) em idosos. Métodos: Estudo transversal com idosos participantes de grupos de convivência no município de Tubarão, Santa Catarina. As variáveis sexo, idade, altura, peso, tabagismo e comorbidades foram autorreferidas. O NAF foi calculado pelo Questionário Internacional de Atividade Física (IPAQ) versão curta. Os dados da VFC foram obtidos com um cardiofrequencímetro, sendo extraídos os componentes FC média (frequência cardíaca média), SDNN (desvio-padrão de todos os intervalos RR), RMSSD (raiz quadrada da média do quadrado das diferenças entre intervalos RR normais adjacentes), RRTri (índice triangular), LF (componente de baixa frequência), HF (componente de alta frequência) e LF/HF (razão entre os componentes de baixa e alta frequência). A FPP foi mensurada com um dinamômetro. Resultados: Participaram 73 idosos com mediana (p25-p75) de idade de 77,0 (68,5 - 77,0) anos, sendo 65 (89%) mulheres. Verificou-se aumento de HF nos homens e RMSSD superior na faixa etária de 70 a 80 anos. Ocorreu diminuição da FC média e aumento de RRTri e LF quando NAF moderado/alto. Um acréscimo de SDNN, RMSSD e HF foi observado em valores diminuídos de FPP das mulheres. Conclusão: Sexo, faixa etária, NAF e FPP das mulheres estiveram associados na modulação autonômica cardíaca, enquanto que IMC, comorbidades, tabagismo e FPP dos homens não interferiram significativamente.

Introduction: The aging process causes changes in the cardiovascular system and affects functional capacity. Objective: To analyze the associations between sociodemographic indicators, body mass index (BMI), comorbidities, level of physical activity (LPA), and grip strength (GS) in heart rate variability (HRV) in the elderly. Methods: A cross-sectional study was carried out with elderly participants of socialization groups in Tubarão, Santa Catarina. The variables sex, age, height, weight, smoking, and comorbidities were self-reported. The LPA was calculated by the short version of the International Physical Activity Questionnaire (IPAQ). The HRV data were obtained with a cardiofrequency meter, and the following components were extracted: mean HR (mean heart rate), SDNN (standard deviation of all RR intervals), RMSSD (square root of the mean square of the differences between adjacent normal RR intervals), RRTri (triangular index), LF (low frequency component), HF (high frequency component) and LF/HF (ratio between low and high frequency components). The measuring of GS was with a dynamometer. Results: 73 elders participated, with a median (p25p75) age of 77.0 (68.5 77.0) years, 65 (89%) of whom were women. An increased HF in men and higher RMSSD in the 70 to 80 years old age group were verified. A decrease in mean HR and an increase in RRTri and LF occurred when moderate/high LPA. The study showed an increase in SDNN, RMSSD, and HF in decreased GS values of women. Conclusion: Sex, age group, LPA, and GS of women were associated with cardiac autonomic modulation, while BMI, comorbidities, smoking, and GS of men did not interfere significantly.

Double Product and Autonomic Function as Predictors of Quality of Life in Heart Transplant Recipients: A Cross-Sectional Study

ABSTRACT Introduction: Heart rate control by the autonomic nervous system (ANS) is impaired in heart transplant (HT) recipients, leading to increased resting heart rate, metabolic demand, and fatigue, which can impair their quality of life (QoL). In this study, we hypothesized the association of hemodynamics and autonomic function as predictors of QoL in HT recipients. Methods: This is a cross-sectional study conducted with HT recipients aged ≥ 18 years at ambulatorial accompaniment. Blood pressure was used for hemodynamics assessment, and heart rate variability (HRV) was used for ANS assessment. QoL was assessed by the 36-item Short Form Health Survey. The significance level was set as P≤0.05. Results: Twenty-two volunteers were included in the study. Systolic blood pressure (SBP) and double product (DP) were significantly negatively associated with the physical functioning domain of QoL. DP, the number of consecutive normal RR interval differences > 50 ms (NN50), and the percentage of normal RR intervals that differed by > 50 ms from the adjacent interval (PNN50) exhibited negative association with the physical role domain. NN50 and PNN50 were significantly associated with bodily pain, social functioning, and emotional role domains. SBP was negatively associated with the vitality domain. Considering general and mental health domains, no variable demonstrated significant association. DP, NN50, and PNN50 were negatively associated with the total score of QoL. Conclusion: This study demonstrated DP and HRV as predictors of QoL in HT recipients. These innovative results can become a relevant therapeutic target for improving QoL in HT recipients prior to its deterioration.

Impact of Air Pollutant on Heart Rate Variability in Healthy Young Adults

Abstract Background: Air pollution and sex independently affect cardiac autonomic control, which can be assessed by heart rate variability (HRV). The research hypothesis is that individuals exposed to low concentrations of pollution have higher cardiac autonomic modulation compared to those exposed to high concentrations and that women have better cardiac autonomic control than men. Objective: To analyze the impact of exposure to air pollutants, specifically smoke, and sex on HRV in healthy young people exposed to different concentrations of pollution over an average period of 22 years. Methods: From April to September 2011, 36 participants of both sexes (20-30 years old) were selected, grouped by levels of air pollution exposure according to indices provided by the Environmental Company of São Paulo State. The R-R intervals (R-Ri) of the electrocardiogram were captured using a heart rate monitor during supine rest. HRV was analyzed by spectral analysis and conditional entropy. The Queen's College step test was used to characterize functional capacity. A between-group comparison was performed using the two-way ANOVA statistical test (post hoc Tukey) and p<0.05. Results: Significant differences were found in mean R-Ri (p<0.01) and cardiac parasympathetic modulation between sexes in the same city (p=0.02) and between groups exposed to different air pollution concentrations (p<0.01). Conclusion: Our results suggest that long-term exposure to air pollutants, specifically smoke, has an unfavorable impact on HRV, with reduced cardiac vagal autonomic modulation in healthy young adults, especially females.

Autonomic and cardiorespiratory responses to the active tilt test in individuals with Parkinson disease: cross-sectional study / Respostas autonômicas e cardiorrespiratórias ao teste ativo de inclinação em indivíduos com doença de Parkinson: estudo transversal

Abstract Background The Parkinson disease (PD) is frequently associated with autonomic dysfunctions. However, data regarding the influence of PD on the autonomic responses to postural changes is limited. Objective To analyze and compare the autonomic responses, evaluated through linear and non-linear methods of heart rate variability, and cardiorespiratory parameters in two groups: Parkinson disease (PDG) and control (CG), at rest and during the active tilt test. Methods A total of 48 participants were analyzed (PDG: n = 25;73.40 ± 7.01 years / CG: n = 23;70.17 ± 8.20 years). The autonomic modulation and cardiorespiratory parameters were evaluated at rest and during the active tilt test. To assess the autonomic modulation the linear indices, at the time (rMSSD, SDNN) and frequency (LF, HF, LF/HF) domains, and the non-linear indices, obtained through the Poincaré plot (SD1, SD2, SD1/SD2), were calculated. The cardiorespiratory parameters evaluated were heart rate (HR), systolic (SBP), and diastolic blood pressure (DBP), peripheral oxygen saturation (SpO2), and respiratory rate. Results At rest, the PDG presented significantly lower values of rMSSD, SDNN, LF, HF, SD1, SD2, and DBP, and higher values of SpO2. During test, in the PD group, modifications were observed in HR, and SBP, besides a reduced parasympathetic response, and an increased global modulation. The qualitative analysis of the Poincaré plot showed that the PDG has a lower dispersion of the RR intervals during rest and the active tilt test. Conclusion Individuals with PD present reduced global variability and parasympathetic modulation at rest, and reduced parasympathetic response and damage in HR regulation when performing the active tilt test, compared with controls.

Resumo Antecedentes A doença de Parkinson (DP) está frequentemente associada a disfunções autonômicas. Porém, dados sobre a influência da DP nas respostas autonômicas às mudanças posturais são limitados. Objetivos Analisar e comparar as respostas autonômicas, avaliadas por métodos lineares e não lineares de variabilidade da frequência cardíaca e parâmetros cardiorrespiratórios em dois grupos: DP (GDP) e controle (CG), em repouso e durante o tilt test ativo. Métodos Foram analisados 48 participantes (GDP: n = 25;73,40 ± 7,01 anos/GC: n = 23; 70,17 ± 8,20 anos). A modulação autonômica e os parâmetros cardiorrespiratórios foram avaliados em repouso e durante o tilt test ativo. Para avaliar a modulação autonômica foram calculados os índices lineares, nos domínios do tempo (rMSSD, SDNN) e frequência (LF, HF, LF/HF), e os índices não lineares, obtidos através do plot de Poincaré (SD1, SD2, SD1/SD2). Os parâmetros cardiorrespiratórios avaliados foram frequência cardíaca (FC), pressão arterial sistólica (PAS), diastólica (PAD), saturação periférica de oxigênio (SpO2) e frequência respiratória. Resultados Em repouso, o GDP apresentou valores menores de rMSSD, SDNN, LF, HF, SD1, SD2 e PAD, e maiores valores de SpO2. No teste, foram observadas modificações na FC e na PAS, redução da resposta parassimpática e aumento da modulação global no GDP. A análise qualitativa do plot de Poincaré mostrou que o GDP apresentou menor dispersão dos intervalos RR no repouso e no tilt test ativo. Conclusão Indivíduos com DP apresentam redução da variabilidade global e modulação parassimpática em repouso, redução da resposta parassimpática e prejuízo na regulação da FC ao realizar o tilt test ativo, em comparação aos controles.