Neuromodulação Vagal Auricular e sua Aplicabilidade em Pacientes com Insuficiência Cardíaca e Fração de Ejeção Reduzida / Auricular Vagal Neuromodulation and its Application in Patients with Heart Failure and Reduced Ejection Fraction

Resumo Fundamento O desequilíbrio do sistema nervoso autônomo (SNA) na insuficiência cardíaca (IC) cria um ciclo vicioso, o excesso de atividade simpática e a diminuição da atividade vagal contribuindo para a piora da IC. A estimulação elétrica transcutânea de baixa intensidade do ramo auricular do nervo vago (taVNS) é bem tolerada e abre novas possibilidades terapêuticas. Objetivos Gerar hipótese da aplicabilidade e benefício da taVNS na IC através da comparação intergrupos de parâmetros ecocardiográficos, teste de caminhada de 6 min, variabilidade da frequência cardíaca pelo Holter (SDNN e rMSSD), questionário de qualidade de vida de Minnesota e classe funcional pela New York Heart Association. Métodos Estudo clínico prospectivo, duplo cego, randomizado com metodologia sham, unicêntrico. Avaliados 43 pacientes e alocados em 2 grupos: o Grupo 1 recebeu taVNS (frequências 2/15 Hz) e Grupo 2 recebeu sham. Nas comparações, valores de p<0,05 foram considerados significativos. Resultados Na fase pós-intervenção, observou-se que o Grupo 1 se manteve com melhor rMSSD (31 x 21; p = 0,046) e atingiu melhor SDNN (110 vs. 84, p = 0,033). Ao compararmos os parâmetros intragrupos, antes e após intervenção, observou-se que todos melhoraram significativamente no grupo 1 e não houve diferenças no grupo 2. Conclusão A taVNS é uma intervenção segura, de fácil execução e que sugere provável benefício na IC pela melhora na variabilidade da frequência cardíaca, o que indica melhor equilíbrio autonômico. Novos estudos com maior número de pacientes são necessários para responder às questões levantadas por esse estudo.

Abstract Background The autonomic nervous system (ANS) imbalance in heart failure (HF) creates a vicious cycle, excess sympathetic activity, and decreased vagal activity contributing to the worsening of HF. Low-intensity transcutaneous electrical stimulation of the auricular branch of the vagus nerve (taVNS) is well tolerated and opens new therapeutic possibilities. Objectives To hypothesize the applicability and benefit of taVNS in HF through intergroup comparison of echocardiography parameters, 6-minute walk test, Holter heart rate variability (SDNN and rMSSD), Minnesota quality of life questionnaire, and functional class by the New York Heart Association. In comparisons, p values <0.05 were considered significant. Methods Prospective, double-blind, randomized clinical study with sham methodology, unicentric. Forty-three patients were evaluated and divided into 2 groups: Group 1 received taVNS (frequencies 2/15 Hz), and Group 2 received sham. In comparisons, p values <0.05 were considered significant. Results In the post-intervention phase, it was observed that Group 1 had better rMSSD (31 x 21; p = 0.046) and achieved better SDNN (110 vs. 84, p = 0.033). When comparing intragroup parameters before and after the intervention, it was observed that all of them improved significantly in group 1, and there were no differences in group 2. Conclusion taVNS is a safe to perform and easy intervention and suggests a probable benefit in HF by improving heart rate variability, which indicates better autonomic balance. New studies with more patients are needed to answer the questions raised by this study.

Comparison of the autonomic nervous system dysfunction between different chronic spine disorders: neck pain versus low back pain

SUMMARY OBJECTIVE: This study aims to compare heart rate variability (HRV) between patients with chronic neck pain and patients with chronic low back pain and to correlate the chronic pain variables with heart rate variability indices. METHODS: This is a cross-sectional study. We divided the sample into two groups: neck pain (n=30) and low back pain (n=30). We used the Numeric Pain Rating Scale, Neck Disability Index, Roland-Morris Disability Questionnaire, Pain-Related Catastrophizing Thoughts Scale, Tampa Scale of Kinesiophobia, and Pain Self-Efficacy Questionnaire. For heart rate variability analysis, we used the following indices: mean RR, standard deviation of all RR intervals, mean heart rate, root mean square differences of successive RR intervals, triangular index, triangular interpolation of the interval histogram, low-frequency band in arbitrary units and in absolute values, high-frequency band in arbitrary units and in absolute values, standard deviation of the instantaneous beat-to-beat variability (standard deviation 1), long-term standard deviation of continuous RR intervals (standard deviation 2), and Stress Index. We used Student's t-test for comparisons and Spearman's coefficient for correlations. RESULTS: We observe insignificant values in the differences between the groups. Disability and self-efficacy were correlated with heart rate variability only in patients with chronic neck pain, whereas catastrophizing and kinesiophobia showed greater correlations with heart rate variability in patients with chronic low back pain. CONCLUSIONS: Autonomic dysfunction of individuals with chronic neck pain, when compared to patients with chronic low back pain, does present insignificant differences.

Introduction of Application of Gini Coefficient to Heart Rate Variability Spectrum for Mental Stress Evaluation / Introdução da Aplicação do Coeficiente de Gini ao Espectro de Variabilidade da Frequência Cardíaca para Avaliação do Estresse Mental

Abstract Background: The Gini coefficient is a statistical tool generally used by economists to quantify income inequality. However, it can be applied to any kind of data with unequal distribution, including heart rate variability (HRV). Objectives: To assess the application of the Gini coefficient to measure inequality in power spectral density of RR intervals, and to use this application as a psychophysiological indicator of mental stress. Methods: Thirteen healthy subjects (19 ± 1.5 years) participated in this study, and their RR intervals were obtained by electrocardiogram during rest (five minutes) and during mental stress (arithmetic challenge; five minutes). These RR intervals were used to obtain the estimates of power spectral densities (PSD). The limits for the PSD bands were defined from 0.15 to 0.40 Hz for high frequency band (HF), from 0.04 to 0.15 Hz for low frequency band (LF), from 0.04 to 0.085 Hz for first low frequency sub-band (LF1) and from 0.085 to 0.15 Hz for second low frequency sub-band (LF2). The spectral Gini coefficient (SpG) was proposed to measure the inequality in the power distribution of the RR intervals in each of above-mentioned HRV bands. SpG from each band was compared with its respective traditional index of HRV during the conditions of rest and mental stress. All the differences were considered statistically significant for p < 0.05. Results: There was a significant decrease in HF power (p = 0.046), as well as significant increases in heart rate (p = 0.004), LF power (p = 0.033), LF2 power (p = 0.019) and LF/HF (p = 0.002) during mental stress. There was also a significant increase in SpG(LF) (p = 0.009) and SpG(LF2) (p = 0.033) during mental stress. Coefficient of variation showed SpG has more homogeneity compared to the traditional index of HRV during mental stress. Conclusions: This pilot study suggested that spectral inequality of Heart Rate Variability analyzed using the Gini coefficient seems to be an independent and homogeneous psychophysiological indicator of mental stress. Also, HR, LF/HF, SpG(LF) of HRV are possibly important, reliable and valid indicators of mental stress.

Resumo Fundamento: O coeficiente de Gini é um instrumento estatístico geralmente usado por economistas para quantificar a desigualdade de renda. No entanto, ele pode ser aplicado a qualquer tipo de dados com distribuição desigual, incluindo a variabilidade da frequência cardíaca (VFC). Objetivos: Avaliar a aplicação do coeficiente de Gini para medir a desigualdade na densidade espectral de potência de intervalos RR, e usar esta aplicação como um indicador psicofisiológico do estresse mental. Métodos: Treze indivíduos saudáveis (19 ± 1,5 anos) participaram deste estudo, e seus intervalos RR foram obtidos por eletrocardiograma durante repouso (cinco minutos) e durante estresse mental (desafio aritmético; cinco minutos). Esses intervalos RR foram utilizados para obter as estimativas de densidades espectrais de potência (PSD). Os limites para as bandas PSD foram definidos de 0,15 a 0,40 Hz para banda de alta frequência (HF), de 0,04 a 0,15 Hz para banda de baixa frequência (LF), de 0,04 a 0,085 Hz para a primeira sub-banda de baixa frequência (LF1) e de 0,085 a 0,15 Hz para a segunda sub-banda de baixa frequência (LF2). O coeficiente de Gini espectral (SpG) foi proposto para medir a desigualdade na distribuição de potência dos intervalos RR em cada uma das bandas de VFC mencionadas acima. O SpG de cada banda foi comparado com seu respectivo índice tradicional de VFC durante as condições de repouso e de estresse mental. Todas as diferenças foram consideradas estatisticamente significativas para p < 0,05. Resultados: Houve uma diminuição significativa no poder de FC (p=0,046), bem como aumentos significativos na frequência cardíaca (p = 0,004), potência da LF (p = 0,033), potência da LF2 (p = 0,019) e LF/HF (p = 0,002) durante estresse mental. Houve também um aumento significativo de SpG(LF) (p = 0,009) e SpG(LF2) (p = 0,033) durante estresse mental. O coeficiente de variação mostrou que o SpG tem mais homogeneidade em comparação com o índice tradicional de VFC durante o estresse mental. Conclusões: Este estudo piloto sugeriu que a desigualdade espectral da VFC analisada pelo coeficiente de Gini parece ser um indicador psicofisiológico independente e homogêneo de estresse mental. Além disso, FC, LF/HF, SpG(LF) da VFC são possivelmente indicadores importantes, confiáveis e válidos de estresse mental.

Is a short-stage protocol during an incremental exercise test reliable for heart rate variability threshold analysis?

Aim: Heart rate variability threshold (HRVT) is a valid method to determine parasympathetic depression during an incremental exercise test (IET). However, HRVT is usually assessed using the last 60s of each 180s stage of an IET, resulting in longer and demotivating tests. This study aimed to evaluate the agreement of HRVT analysis adopting the first and second minute of R-R interval (iRR) segment comparatively to a standard third-minute segment obtained at each 3-min stage on IET. Methods: Seventeen young male subjects (22.2 ± 3.1 years; 23.4 ± 2.3 kg/m2) underwent IET on a cycle ergometer. HRVT was considered the load corresponding to the point of stabilization of the SD1 index (HRVTV), or the first load with SD1 value < 3ms (HRVT<3), both assessed by the 1st (HRVT1V, HRVT1<3), 2nd (HRVT2V, HRVT2<3) and standard 3rd (HRVT3V, HRVT3<3) 60s iRR segment analyzed at each stage of IET. Agreement and reliability were assessed by the Bland-Altman analysis and the intraclass correlation coefficient (ICC), respectively. Results: High reliability and non-significant bias were observed considering HRVT1V vs HRVT3V (ICC = 0.92; p = 0.18) or HRVT2V vs HRVT3V (ICC = 0.94; p = 0.99). However, lower reliability was observed for HRVT1<3 vs HRVT3<3 (ICC = 0.79; p = 0.75) and for HRVT2<3 vs HRVT3<3 (ICC = 0.91; p = 0.33). Conclusion: HRVT can be similarly assessed by the 1st, 2nd or 3rd 60 seconds iRR segment, mainly when assessed by a visual method.(AU)

A pilot study on the role of autonomic function testing in predicting hypotension in patients undergoing cesarean section under spinal anesthesia

BACKGROUND: Maternal hypotension is a common complication during obstetric spinal anesthesia. This study was conducted to investigate the role of autonomic function testing in predicting maternal hypotension during spinal anesthesia induced to conduct Cesarean sections (C-section). METHODS: This study was conducted on 32 parturients undergoing C-section under spinal anesthesia. Sympathetic function tests included measuring diastolic blood pressure changes in response to hand gripping and systolic blood pressure changes response to moving from a supine to a standing position. Sympathetic dysfunction is said to exist when there are abnormal responses to both sympathetic function tests. Parasympathetic function tests included measuring heart rate responses to deep breathing and heart rate responses to moving from a supine to a standing position. Parasympathetic dysfunction is said to exist when there are abnormal responses to both parasympathetic function tests. After the onset of spinal anesthesia, blood pressure was measured every minute until childbirth. RESULTS: Hypotension occurred in 22 of the 32 parturients. There was no correlation between sympathetic dysfunction and hypotension incidence, but 12 of the 12 (100%) of the positive group and 10 of the 20 (50%) of the negative group experiencing parasympathetic dysfunction, respectively, experienced hypotension with a significant difference of P = 0.004. The group experiencing parasympathetic dysfunction had statistically significantly higher phenylephrine requirements were also greater in the parasympathetic dysfunction positive group (P < 0.003). CONCLUSIONS: This study's findings suggested that the parasympathetic function tests may be useful methods for predicting the incidence of maternal hypotension during spinal anesthesia induced for C-section.

Impact of heart rate on reproducibility of heart rate variability analysis in the supine and standing positions in healthy men

OBJECTIVE: The reliability of heart rate variability (HRV) analysis is not yet fully understood, especially considering different body positions and the mathematical influence of heart rate. The aim of this study was to evaluate the reliability of HRV in supine and standing positions, with and without mathematical adjustment of HRV by the average R-R interval (iRR). METHODS: We evaluated 37 young males (23.1±4 years; 25.1±3 kg/m2). A 5-min segment of the iRR was collected in the supine and standing positions on three occasions separated by 48-hour intervals. Absolute and relative reliability of temporal and spectral indices were assessed by the coefficient of variation (CV) and the intraclass correlation coefficient (ICC), respectively. RESULTS: We did not observe differences in HRV indices in the three occasions in the supine or standing position (p>0.05). Moderate to good reproducibility was observed for temporal and spectral indices of HRV in the supine position (ICC: 0.65-0.89; CV: 0.9-19.8). In the orthostatic position, low to good reproducibility was observed (ICC: 0.35-0.89; CV: 1.1-34.8), with higher ICCs for temporal indices. After mathematical adjustment, only a small modification in HRV reliability was observed in both positions. CONCLUSIONS: In young adult males, the mathematical adjustment of HRV by the average iRR led to a nonsignificant effect on HRV reliability. Additionally, HRV reliability is dependent on body position and the index analyzed. Promising measures in both supine and standing positions include r-MSSD and the HF band (parasympathetic indices).

EFEITO DE DIFERENTES PROTOCOLOS DE RECUPERAÇÃO SOBRE A FUNÇÃO AUTONÔMICA CARDÍACA / EFFECT OF DIFFERENT RECOVERY PROTOCOLS ON THE CARDIAC AUTONOMIC FUNCTION / EFECTO DE DIFERENTES PROTOCOLOS DE RECUPERACIÓN SOBRE LA FUNCIÓN AUTONÓMICA CARDIACA

RESUMO Introdução: A avaliação da função autonômica cardíaca (FAC) após o teste de esforço (TE) é considerada um preditor poderoso e independente de risco cardiovascular. É escasso o conhecimento da influência de diferentes protocolos de recuperação sobre a FAC após TE em esteira rolante com os voluntários na posição ortostática. Objetivo: Comparar a reativação vagal e o grau de modulação global da FAC em dois diferentes protocolos de recuperação, passiva (RP) e ativa (RA), imediatamente após TE submáximo em esteira rolante. Métodos: Foram avaliados 24 homens fisicamente ativos com idade (média ± DP) de 27,2 ± 4,4 anos e IMC 24,8 ± 1,8 kg/m2. A ordem dos protocolos de recuperação foi definida de forma aleatória. Os testes foram realizados com intervalo de sete dias. Ambas as recuperações foram realizadas na posição ortostática durante cinco minutos, imediatamente após TE. Os índices temporais da variabilidade da frequência cardíaca foram utilizados para avaliar a reativação vagal e o grau de modulação global de FAC, rMSSD e SDNN, respectivamente, na RP e RA. Após análise da distribuição dos dados, utilizaram-se os testes de Mann-Whitney e de Friedman com post-hoc de Dum, no nível de significância de p ≤ 0,05. Resultados: Verificou-se maior reativação vagal no primeiro minuto de recuperação na RP comparativamente a RA [4,1 (4,9-3,4) ms vs. 3,4 (4,0-2,9) ms, p = 0,03] e maior grau de modulação global da FAC do terceiro ao quinto minuto e tendência a diferença significativa no segundo minuto de RP comparativamente a RA (p = 0,09-0,005). Conclusão: Os achados demonstram que o mínimo esforço físico, como caminhar lentamente sobre a esteira rolante, diminuiu a reativação vagal e o grau de modulação global da FAC após o TE submáximo em homens fisicamente ativos.

ABSTRACT Introduction: The evaluation of cardiac autonomic function (CAF) after stress test (ST) is considered a powerful and independent predictor of cardiovascular risk. The knowledge about the influence of different recovery protocols on CAF after ST on treadmill with volunteers in standing position is scarce. Objective: To compare the vagal reactivation and the degree of global CAF modulation in two different recovery protocols, passive (PR) vs. active (AR) immediately after submaximal ST in treadmill. Methods: We evaluated 24 physically active males, aged (mean ± SD) 27.2 ± 4.4 years and BMI 24.8 ± 1.8 kg/m2. The order of the recovery protocol was set at random. The tests were performed in 7-day intervals. Both recovery protocols were performed in standing position for 5 minutes, immediately after ST. The time indices of heart rate variability were used to assess the vagal reactivation and the overall degree of CAF, rMSSD, and SDNN, respectively, in PR and AR. After analysis of the data distribution, the Mann-Whitney and Friedman tests with Dum post-hoc were used at a significance level of p ≤ 0.05. Results: We observed a higher vagal reactivation at first minute of the PR compared to AR [4.1 (4.9-3.4) ms vs. 3.4 (4.0-2.9) ms, p = 0.03], and a higher degree of global CAF modulation from the third to the fifth minute and a tendency to significant difference in the second minute of PR compared to AR (p = 0.09−0.005). Conclusion: The findings demonstrate that minimum physical effort, such as walking slowly on a treadmill, decreased the vagal reactivation and the overall modulation degree of CAF after a submaximal ST in physically active men.

RESUMEN Introducción: La evaluación de la función autonómica cardíaca (FAC) después de la prueba de esfuerzo (PE) se considera un predictor potente e independiente del riesgo cardiovascular. Es escaso el conocimiento de la influencia de los diferentes protocolos de recuperación sobre la FAC después de la PE en la cinta rodante con voluntarios en la posición de pie. Objetivo: Comparar la reactivación vagal y el grado de la modulación general de la FAC en dos diferentes protocolos de recuperación, pasiva (RP) vs. activa (RA) inmediatamente después de la PE submáxima en la cinta rodante. Métodos: Se evaluaron 24 hombres físicamente activos con edades (promedio ± DE) de 27,2 ± 4,4 años y IMC de 24,8 ± 1,8 kg/m2. El orden de los protocolos de recuperación se definió al azar. Las pruebas se realizaron en un intervalo de siete días. Ambas recuperaciones se realizaron en la posición de pie durante cinco minutos inmediatamente después de la PE. Los índices temporales de la variabilidad de la frecuencia cardiaca fueron utilizados para evaluar la reactivación vagal y el grado de modulación general de la FAC, rMSSD y SDNN, respectivamente, en RP y RA. Después del análisis de la distribución de los datos, se utilizaron la prueba de Mann-Whitney y la de Friedman con post-hoc de Dum, a un nivel de significación de p ≤ 0,05. Resultados: Se observó una mayor reactivación vagal en el primer minuto de la PR comparada a la RA [4,1 (4,9-3,4) ms vs. 3,4 (4,0-2,9) ms, p = 0,03] y un mayor grado de modulación general de la FAC del tercer al quinto minuto y una tendencia a la diferencia estadística en el segundo minuto de RP comparada a RA (p = 0,09-0,005). Conclusión: Los resultados muestran que el esfuerzo físico mínimo, como caminar lentamente sobre la cinta rodante, disminuyó la reactivación vagal y el grado de modulación general de la FAC después de la PE submáxima en hombres físicamente activos.

Cardiac arrest attributable to dysfunction of the autonomic nervous system after traumatic cervical spinal cord injury / 中华创伤杂志(英文版)

Bradycardia is the most common form of dysrhythmia developing after disruption of the sympathetic pathway by a spinal cord injury (SCI), and it can have fatal consequences, including cardiac arrest. Here, we report a case of cardiac arrest developing after cervical SCI attributable to sympathetic hypoactivity. A 26-year-old male pedestrian was admitted after a traffic accident. Radiologically, fractures were apparent at the Cbilateral articular facets, and cord contusion with hemorrhage was evident at C. During his stay in ICU, intermittent bradycardia was noted, but the symptoms were not specific. On the 22nd postoperative day, the patient was taken to the computed tomography suite for further evaluation and experienced cardiac arrest during a positional change. After immediate cardiac massage, the patient was resuscitated. We scheduled Holter monitoring, which detected 26 pauses, the longest of which was 17.9 s. The patient underwent cardiac pacemaker insertion. No further cardiac events were noted.

Heart Rate Variability Among Children With Acquired Brain Injury

OBJECTIVE: To find evidence of autonomic imbalance and present the heart rate variability (HRV) parameters that reflect the severity of paroxysmal sympathetic hyperactivity (PSH) in children with acquired brain injury (ABI). METHODS: Thirteen children with ABI were enrolled and age- and sex-matched children with cerebral palsy were selected as the control group (n=13). The following HRV parameters were calculated: time-domain indices including the mean heart rate, standard deviation of all average R-R intervals (SDNN), root mean square of the successive differences (RMSSD), physical stress index (PSI), approximate entropy (ApEn); successive R-R interval difference (SRD), and frequency domain indices including total power (TP), high frequency (HF), low frequency (LF), normalized HF, normalized LF, and LF/HF ratio. RESULTS: There were significant differences between the ABI and control groups in the mean heart rate, RMSSD, PSI and all indices of the frequency domain analysis. The mean heart rate, PSI, normalized LF, and LF/HF ratio increased in the ABI group. The presence of PSH symptoms in the ABI group demonstrated a statistically significant decline of the SDNN, TP, ln TP. CONCLUSION: The differences in the HRV parameters and presence of PSH symptoms are noted among ABI children compared to an age- and sex-matched control group with cerebral palsy. Within the ABI group, the presence of PSH symptoms influenced the parameters of HRV such as SDNN, TP and ln TP.

Correlation between sleep quality and parasympathetic intensity at nighttime / 中华神经科杂志

Objective To clarify the effect of cardio pulmonary coupling (CPC) technology on sleep quality and the effect of Shichen-based physiological function index analysis on sleep health assessment.Methods CPC and Shichen-based physiological function index were used to evaluate the sleep quality of 242 volunteers from 9:00 pm to 9:00 am for 12 hours.Based on CPC technology score,volunteers wree seperated to three sleep quality groups (scoring 85-100 in 63 volunteers,scoring 60-84 in 80 volunteers,scoring ＜ 60 in 99 volunteers).The results of sleep quality and parasympathetic intensity over the whole nighttime and the different time period of each sleep quality group were compared and the correlation analysis was done.Results The whole nighttime sleep quality test showed that there was significant difference (t =-12.754-19.030,all P ＜ 0.01) in the time to the stable sleep ratio (52.78％ ± 10.32％,43.99％ ± 14.48,20.95％ ± 10.41％),the disturbed sleep ratio (25.65％ ± 7.81％,34.18％ ± 12.71％,53.65％ ± 14.81％),and the apnea-hypopnea index (2.79 ±2.95,7.93 ± 6.61,23.94 ± 16.09)in the different sleep quality groups.The Shichen-based sleep quality test showed that there was significant difference among the stable sleep ratio,the disturbed sleep ratio during the 23:00 pm to 5:00 am period in the different sleep quality groups.There existed significant difference with parasympathetic intensity in the different sleep quality groups.There was positive correlation between the parasympathetic intensity and the stable sleep ratio in the same sleep quality group (r =0.508,P ＜ 0.05).Conclusions CPC evaluation can commendably distinguish and evaluate different sleep quality groups on the whole night sleep.The Shichen-based physiological function index can not only distinguish the sleep quality,but also evaluate the multiple physiological function,the parasympathetic intensity between different sleep quality groups during different sleep periods.Thus they can be widely used to assess the sleep quality.

Modulação da função autonômica cardíaca e incontinência urinária feminina / Modulation of cardiac autonomic function and female urinary incontinence

Introdução: O Sistema Nervoso Autônomo (SNA) atua nas fases de enchimento e esvaziamento da bexiga, controlados pelo SNA simpático e o parassimpático. Objetivo: Revisar a literatura a respeito da aplicação da análise da Variabilidade da Frequência Cardíaca (VFC) na Incontinência Urinária (IU). Método: Revisão narrativa de literatura. Realizou-se a busca nas bases de dados Medline, Pubmed e Bireme. Critérios de inclusão: artigos científicos que contemplassem o tema proposto, publicados em português ou inglês, no período de 2005 a 2014. Excluíram-se trabalhos que envolvessem a VFC associada a outras doenças, outras circunstâncias e IU masculina, estudos realizados com crianças e experimentais com animais, pesquisas com enfoque farmacológico, monografias, dissertações e teses. Resultados: Foram selecionados 8 artigos que se encaixaram nos critérios de inclusão. Os estudos analisados sugerem que o desequilíbrio do SNA pode estar relacionado às disfunções urinárias. A VFC pode servir como uma ferramenta para avaliar a atividade do SNA alterada em pacientes com disfunção urológica. Conclusão: A VFC é uma ferramenta simples e não-invasiva que permite a compreensão da função do SNA simpático e parassimpático na atividade urológica. A análise de VFC ainda é pouco explorada no âmbito da Fisioterapia em Saúde da Mulher, tornando necessários estudos futuros. (AU)

Introduction: The Autonomic Nervous System (ANS) acts in the bladder filling and emptying stages, which are controlled by the sympathetic and parasympathetic systems. Objective: To review the literature in respect to Heart Rate Variability (HRV) in Urinary Incontinence (UI). Method: This is a narrative review of the literature. A search on Medline, Pubmed and Bireme databases was performed. Inclusion criteria: Scientific articles that addressed the proposed theme, published in Portuguese or English, within the period of 2005 to 2014. Research work involving Cardiac Autonomic Modulation associated with other diseases, other circumstances and male UI, studies with children and experimental animals, pharmacological studies, monographs, dissertations and theses were excluded. Results: Eight articles fitting the criteria were selected. The analyzed studies suggest that the imbalance in the ANS may be associated to urinary dysfunction. HRV can be employed as a tool to evaluate altered autonomic nervous activity in patients with urological dysfunction. Conclusion: HRV is a simple and non-invasive tool which provides comprehension of sympathetic and parasympathetic ANS function in women's urological activity. HRV analysis is little explored in the context of Women's Health Physiotherapy making future studies warranted. (AU)

¿Es la grasa abdominal subcutánea un predictor de la variabilidad cardíaca en hombres con bajo riesgo metabólico? / Is the abdominal subcutaneous fat a predictor of heart rate variability in men with low metabolic risk?

Introducción: Aunque el sobrepeso/obesidad, adiposidad aumentada e inactividad física se asocian a menor variabilidad cardíaca y desregulación autonómica, no se ha explorado en detalle la relación entre estos factores en sujetos de bajo riesgo metabólico. Objetivo: Analizar el tipo y fuerza de asociación entre la variabilidad cardíaca en reposo y la adiposidad en hombres jóvenes, delgados y físicamente activos. Metodología: Estudio descriptivo transversal. Se analizaron los componentes espectrales de la variabilidad cardíaca en 24 hombres de 18-30 años físicamente activos, con peso y adiposidad normales. Se realizaron análisis de regresión lineal múltiple para explicar la variabilidad cardíaca en función de la relación cintura/cadera, pliegue abdominal y actividad física. Resultados: El volumen de actividad física semanal se relacionó positivamente con RMSSD y HF, y negativamente con LF y LF/HF. La relación cintura/cadera y el pliegue abdominal se relacionaron positivamente con HF y negativamente con LF y LF/HF. En todos los casos, los coeficientes de regresión β tipificados estuvieron entre 0,395 y 0,505 (p<0,05). El índice de grasa visceral calculado a partir de bioimpedancia no mostró relación alguna. Conclusiones: Los hallazgos aquí reportados son indicativos de que en hombres jóvenes, delgados y físicamente activos, la actividad física y la grasa subcutánea se relacionan positivamente con el tono vagal y negativamente con el tono simpático, lo que lleva a postular que la acumulación del exceso calórico en forma de tejido adiposo subcutáneo (y no visceral) podría ser un mecanismo de protección contra el desarrollo de síndrome metabólico en estos sujetos.

Objective: To measure the type and strength of the potential association between heart rate variability at rest and some indicators of adiposity in young, lean, and physically active men. Introduction: Although overweight/obesity, increased adiposity and physical inactivity are associated with decreased heart rate variability and autonomic dysregulation, the relationship between these factors has not been explored in detail in subjects with low metabolic risk: normal weight, low adiposity and physically active. Methodology: Cross-sectional analytical study. The spectral components of heart rate variability were analyzed in 24 physically active men, 18-30 years old, with normal weight and adiposity. Multiple linear regression analysis was performed to explain heart rate variability as a function of waist to hip ratio, abdominal skinfod and physical activity. Results: The volume of weekly physical activity was positively related to RMSSD and HF, and negatively with LF and LF/HF. Both the waist to hip ratio and abdominal skinfold were positively related with HF, and negatively with LF and LF/HF. In all cases, the B regression standardized coefficients were between 0.395 and 0.505 (p<0.05). The visceral fat rating calculated from bioimpedance showed no relation. Conclusions: The findings reported here are indicative that in young, lean and physically active men, physical activity and subcutaneous fat are positively related to vagal tone and negatively with sympathetic tone. This leads us to postulate that the accumulation of caloric excess in the form of subcutaneous adipose tissue (not visceral) might be a protective mechanism against the development of metabolic syndrome in these subjects.

Heart Rate Variability for Quantification of Autonomic Dysfunction in Fibromyalgia

OBJECTIVE: To quantify autonomic dysfunction in fibromyalgia patients compared to healthy controls using heart rate variability (HRV). METHODS: Sixteen patients with fibromyalgia and 16 healthy controls were recruited in this case control study. HRV was measured using the time-domain method incorporating the following parameters: total heartbeats, the mean of intervals between consecutive heartbeats (R-R intervals), the standard deviation of normal to normal R-R intervals (SDNN), the square root of the mean squared differences of successive R-R intervals (RMSSD), ratio of SDNN to RMSSD (SDNN/RMSSD), and difference between the longest and shortest R-R interval under different three conditions including normal quiet breathing, rate controlled breathing, and Valsalva maneuver. The severity of autonomic symptoms in the group of patients with fibromyalgia was measured by Composite Autonomic Symptom Scale 31 (COMPASS 31). Then we analyzed the difference between the fibromyalgia and control groups and the correlation between the COMPASS 31 and aforementioned HRV parameters in the study groups. RESULTS: Patients with fibromyalgia had significantly higher SDNN/RMSSD values under both normal quiet breathing and rate controlled breathing compared to controls. Differences between the longest and shortest R-R interval under Valsalva maneuver were also significantly lower in patients with fibromyalgia than in controls. COMPASS 31 score was negatively correlated with SDNN/RMSSD values under rate controlled breathing. CONCLUSION: SDNN/RMSSD is a valuable parameter for autonomic nervous system function and can be used to quantify subjective autonomic symptoms in patients with fibromyalgia.

Vagotomy ameliorates islet morphofunction and body metabolic homeostasis in MSG-obese rats

The parasympathetic nervous system is important for β-cell secretion and mass regulation. Here, we characterized involvement of the vagus nerve in pancreatic β-cell morphofunctional regulation and body nutrient homeostasis in 90-day-old monosodium glutamate (MSG)-obese rats. Male newborn Wistar rats received MSG (4 g/kg body weight) or saline [control (CTL) group] during the first 5 days of life. At 30 days of age, both groups of rats were submitted to sham-surgery (CTL and MSG groups) or subdiaphragmatic vagotomy (Cvag and Mvag groups). The 90-day-old MSG rats presented obesity, hyperinsulinemia, insulin resistance, and hypertriglyceridemia. Their pancreatic islets hypersecreted insulin in response to glucose but did not increase insulin release upon carbachol (Cch) stimulus, despite a higher intracellular Ca2+ mobilization. Furthermore, while the pancreas weight was 34% lower in MSG rats, no alteration in islet and β-cell mass was observed. However, in the MSG pancreas, increases of 51% and 55% were observed in the total islet and β-cell area/pancreas section, respectively. Also, the β-cell number per β-cell area was 19% higher in MSG rat pancreas than in CTL pancreas. Vagotomy prevented obesity, reducing 25% of body fat stores and ameliorated glucose homeostasis in Mvag rats. Mvag islets demonstrated partially reduced insulin secretion in response to 11.1 mM glucose and presented normalization of Cch-induced Ca2+ mobilization and insulin release. All morphometric parameters were similar among Mvag and CTL rat pancreases. Therefore, the higher insulin release in MSG rats was associated with greater β-cell/islet numbers and not due to hypertrophy. Vagotomy improved whole body nutrient homeostasis and endocrine pancreatic morphofunction in Mvag rats.

Effect of dl-3n-butylphthalide on sympathetic remodeling at infarct border zone in rats with myocardial infarction / 中华老年医学杂志

Objective To investigate the effect of dl-3n-Butylphthalide (NBP) on cardiac function and sympathetic remodeling in rats with myocardial infarction (MI).Methods Totally 50 male SD rats were randomly divided into 3 groups:Sham-operated (sham) group (n 10),myocardial infraction (MI) group (n=20) and MI with NBP group (n=20).A rat myocardial infarction model was established by ligating anterior descending branch of coronary artery.Rats in MI with NBP group were received the gavage treatment with NBP.Cardiac function was evaluated by hemodynamic detection at 7 day post-MI.Cardiac tissues were stained with hematoxylin and eosin as well as Masson trichrome.The distribution and density of growth associated protein-43-(GAP-43) and tyrosine hydroxytase-(TH) positive nerve at infarction border zone were detected by immunohistochemistry.The activation of nuclear factor-κB (NF-κB) signaling pathway was detected by western blot analysis.Results 8 rats died in MI group,in which 2 rats died within 24h.7 rats died in MI with NBP group,and in which 3 rats died within 24 h.The left ventricular end-diastolic pressure (LVEDP) and left ventricular end-systolic pressure (LVESP) were (7.81 ± 2.46) mmHg (1 mmHg=0.133 kPa) and (103.32±10.59) mmHg,(18.93±3.17) mmHg and (136.44±13.62) mmHg,(16.56±4.82) mmHg and (112.83±16.97) mmHg in sham group,MI group and MI with NBP group respectively.There were no significant differences in + dP/dt and-dP/dt between MI group and MI with NBP group (both P＞0.05).Compared with sham group,the collagen volume fraction at infarct border zone was increased in MI group (P＜0.05),but was reduced in MI with NBP group as compared to the MI group (P＜0.05).The densities of GAP-43-and TH-positive nerves at infarct border zone were increased in MI group as compared with sham group,and reduced in MI with NBP group as compared with MI group (both P＜0.05).NBP could reduced p IKBα protein expression and increase IKBα protein expression in rats with MI.Conclusions NBP may improve the sympathetic remodeling after MI via the inhibition of NF-κB signaling pathway.

Clinical Neuroanatomy and Neurotransmitter-Mediated Regulation of Penile Erection / 대한배뇨장애요실금학회지

Erectile dysfunction (ED) has an adverse impact on men's quality of life. Penile erection, which is regulated by nerves that are innervated into the erectile tissue, can be affected by functional or anatomical trauma of the perineal region, including specific structures of the penis, causing ED. Penile erection is neurologically controlled by the autonomic nervous system. Therefore, it is of utmost importance to understand the neurogenic structure of the erectile tissue and the types of neurotransmitters involved in the penile erection process. Here, we highlight the basic clinical anatomy and erectile function of the penis. Understanding the clinical connotation of the relationship between penile erectile structure and function may provide fresh insights for identifying the main mechanisms involved in ED and help develop surgical techniques for the treatment of ED.

Comparação da resposta autonômica cardiovascular de praticantes de musculação, corredores de longa distância e não praticantes de exercício / Comparison of cardiovascular autonomic response among body builders, long distance runners and non-trained

Objetivou-se comparar a resposta autonômica cardiovascular (RAC) de praticantes de musculação, corredores de longa distância e não praticantes de exercício. Homens, 21 a 55 anos, foram agrupados em: Praticantes Musculação (PM, n = 31); Praticantes Corrida (PC, n = 28); Controle (C, n = 35). Foram selecionadas quatro técnicas para avaliação da RAC: Frequência cardíaca de repouso (FCR), Teste pressórico do frio (TPF), Variabilidade da FC (VFC) e recuperação da FC pós-teste máximo em esteira. A FCR foi menor no grupo PC (PC = 54 ± 2; PM= 62 ± 2; C = 65 ± 2 bpm; média ± EPM). A recuperação da FC aos 60 s pós-teste de esforço foi maior no grupo PC (PC = 34 ± 3; PM = 23 ± 1; C = 24 ± 2; bpm). Quanto aos parâmetros espectrais de alta (HF) e baixa (LF) frequência da VFC, o grupo PC apresentou maior HF (55,1 ± 4,0 n.u) e menor LF (43,1 ± 4,0 n.u) comparado ao grupo C (HF = 40,7 ± 3,3; LF = 56,7 ± 3,5 n.u). O grupo PM não apresentou qualquer diferença de RAC em comparação ao grupo C. Conclui-se que prática contínua em musculação por longo prazo, diferentemente da prática de corrida de longa distância, não é capaz de alterar significativamente a RAC.

The aim of the study was to compare the cardiovascular autonomic response (CAR) of recreational weight trainers, long distance runners and non-exercised subjects. Men, 21 to 55 years old, were grouped in: recreational weight trainers (W, n = 31), long distance runners (R, n = 28) and non-exercised (C, n = 35). Four strategies of evaluation of the CAR were selected: Resting heart rate (RHR), cold pressor test (CPT), heart rate variability (HRV) and heart rate recovery (HHR) following maximal exercise test. The RHR was lower (R = 54 ± 2; W = 62 ± 2; C= 65 ± 2 bpm; mean ± SE) and the HHR 60s post exercise was larger in the R group (R = 34 ± 3; W = 23 ± 1; C = 24 ± 2 bpm). The R group presented larger high-frequency (HF; 55.1 ± 4.0 n.u) and smaller low-frequency (LF; 43.1 ± 4.0 n.u) components of HRV than C group (HF = 40.7 ± 3.3; LF = 56.7 ± 3.5 n.u.). The W group did not show any differences compared to C group. The study's conclusion was that long-term weight-training program, unlike of long-term running training, it is not able to alter significantly the regulatory pattern of CAR.

Treinamento para disfunção vagal cardíaca com repetições da transição repouso-exercício / Training for cardiac vagal dysfunction with repetitions of rest-exercise transition

Disfunção vagal cardíaca está associada com um pior prognóstico clínico e um dos potenciais benefícios do exercício físico regular é aumentar o tônus vagal cardíaco (TVC). Como nas transições repouso-exercício-repouso o TVC é rapidamente inibido e reativado, hipotetizou-se que um treinamento repetido desta transição - denominado treinamento vagal (TV) -, em indivíduos com TVC reduzido, poderia reverter essa disfunção. Participantes que ingressaram em um programa de exercício supervisionado (PES) com índice vagal cardíaco (IVC) baixo (? 1,30 no teste de exercício de quatro segundos) foram randomizados para um estudo com delineamento cruzado (duas etapas de oito semanas), com ou sem três sessões semanais de TV. O TV consistiu de cinco repetições em 5s de pedalada rápida sem carga com 55 s de intervalo em repouso. Após rígidos critérios de inclusão e exclusão (controle de uso de medicação, condição clinica e aderência ao PES) 44 pacientes (64% homens; 65,5 ±11,4 anos) finalizaram o estudo. Houve discreta melhora no IVC ao final de 16 semanas (1,19 vs 1,22; p=0,02), mas não se pôde afirmar que a diferença no IVC se deveu ao período em que foi realizado o TV (p=0,36). Portanto, 16 semanas de PES incluindo oito semanas de TV aumentou a resposta vagal à transição repouso-exercício, embora não tenha sido possível atribuir os resultados exclusivamente ao TV. Futuros estudos são necessários para esclarecer se o TV, com maior número de repetições e/ou período de duração mais longo, poderá promover uma melhora mais acentuada do TVC em indivíduos com níveis iniciais baixos...

Vagal dysfunction is related to a worse clinical prognosis and one of the potential benefits of regular exercise is to increase cardiac vagal tone (CVT). Since CVT is quickly inhibited and reactivated in the fast rest-exercise-rest transition, it was hypothesized that a training of this transition ? called vagal training (VT) - in individuals with reduced CVT could reverse this condition. Patients with low cardiac vagal index (CVI) (? 1.30 on the 4-second exercise test) starting a supervised exercise program (SEP) were randomized in a crossover design (two phases, eight weeks each), with or without three weekly VT sessions. VT consisted of five repetitions of sudden, fast unloaded pedaling for five seconds in a cyclergometer, and resting seated for 55 seconds. After applying strict inclusion and exclusion criteria (medication use, clinical condition and adherence to SEP), 44 patients (64 % men and 65.5 ± 11.4 years) completed the study. There was a slight improvement in the CVI at the end of 16 weeks (1.19 vs 1.22, p = 0.02), but it could not be stated this difference was due to the VT (p = 0.36). Therefore, 16 weeks of SEP, including eight weeks of VT training, increased the CVI of those with lower CVI, but this improvement could not be attributed exclusively to the additional VT. Further studies are needed to clarify if more repetitions or a longer period of VT would promote even greater CVT recovery...

The Effects of combined aerobic and resistance training on heart rate variability in postmenopausal women / Efeitos do treinamento aeróbio e resistido combinados na variabilidade da frequência cardíaca em mulheres na menopausa

Model of the study: Controlled clinical trial. Objective: To verify the effects of 16 weeks of combined aerobic and resistance training on cardiac autonomic modulation in menopausal women. Methods: 17 menopausal women were divided into two groups: the training group (TG: n=11) and control group (CG:n=6). The body composition variables were estimated using dual-energy X-ray absorptiometry. The cardiac autonomic modulation was evaluated by heart rate variability using linear indexes. The training protocol consisted of 16 weeks of 50 minutes of resistance training and 30 minutes of aerobic training. Results: For the TG there was an increase in the rMSSD(ms) index (pre:17,4±3,7 and post:24,8±13,1,p<0,045), an increase in the duration of the intervals between the cardiac beats (ms) (pre:891,2±80,2 andpost:974,1±71,4, p<0,003) and in the values of heart rate (bpm) (pre:68,1±6,4 and post:62,0±4,7, p<0,003), additionally for the spectral indexes in normalized units, changes for LF (pre:52,2±13,1 and post:44,5±12,4, p<0,025) and HF (pre:47,8±13,3 and post:55,5±12,4, p<0,025) were noticed, demonstrating increased parasympathetic and reduced sympathetic. There were no significant differences to CG. Conclusion: combined aerobic and resistance training promoted benefits to the autonomic modulation in menopausal women.

Modelo do estudo: Ensaio clínico controlado. Objetivo: Verificar a resposta de 16 semanas do treinamento aeróbio e resistido combinado sobre a modulação autonômica em mulheres na menopausa. Métodos: 17 mulheres foram divididas em dois grupos: grupo treino (GT: n=11) e grupo controle (GC:n=6). As variáveis de composição corporal foram estimadas pela absorptiometria radiológica de dupla energia. A modulação autonômica foi avaliada pela variabilidade da frequência cardíaca usando índices lineares. O protocolo de treinamento consistiu em 16 semanas, por 50 minutos de treinamento resistido e 30 minutos de treinamento aeróbio. Resultados: Para o GT houve incremento do índice rMSSD (ms) (pre:17,4±3,7 e pos: 24,8±13,1, p<0,045), aumento dos intervalos entre batimentos cardíacos consecutivos (pre:891,2±80,2 e pos:974,1±71,4, p<0,003) e dos valores de frequência cardíaca (bpm) (pre:68,1±6,4 e pos:62,0±4,7, p<0,003), para os índices espectrais em unidades normalizadas, houve redução de LF (pre:52,2±13,1 e pos:44,5±12,4, p<0,025) e incremento de HF (pre:47,8±13,3 e pos:55,5±12,4, p<0,025).Não houve diferenças significantes para o GC. Conclusão: o treinamento aeróbio e resistido combinado promoveu benefícios sobre a modulação autonômica em mulheres na menopausa.