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1.
Environ Sci Pollut Res Int ; 27(4): 4170-4177, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31828705

RESUMO

The aim of this study was to investigate the autonomic modulation of heart rate in healthy individuals exposed to long-term air pollution through geometric methods. We analyzed data from 109 healthy adults aged 18 to 49, divided into three groups according to the exposure time: period 0 to 15 years of exposure (n = 29), more than 15 years of exposure (n = 31), and control group (n = 49). For the analysis of heart rate variability (HRV), heart rate was recorded beat-to-beat for 20 min in the sitting position. The RR intervals were transformed into geometric indexes, and from them, we calculated the RRTri (triangular index), TINN (triangle interpolation of histogram of intervals NN), and Poincaré plot (SD1, SD2, and SD1/SD2). Significantly lower values were observed in the group of individuals exposed to air pollution for more than 15 years compared with the group of individuals exposed to air pollution for a period of 0-15 years and those not exposed for the RRTri (11.5 vs 13.8 vs 14.0), SD1 (16.4 vs 20.5 vs 20.6), SD2 (60.5 vs 68.1 vs 72.5), and SD1/SD2 (0.27 vs 0.34 vs 0.31), with the effect of this difference being considered large (RRTri), medium (SD1, SD1/SD2), and small (SD2). TINN was not significantly different among groups (198.2 vs 223.1 vs 233.6). Healthy individuals exposed to air pollution for more than 15 years present an autonomic imbalance, characterized by lower parasympathetic modulation and overall HRV.

2.
Medicina (Kaunas) ; 55(9)2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31454929

RESUMO

Background: Metabolic syndrome (MetS) influences the autonomic modulation, increasing the risk of cardiovascular events, which demands the identification of effective treatments for this population. Considering this, the study has the objective of evaluating the effects of periodized aerobic interval training (AIT) on geometrical methods of heart rate variability (HRV) on individuals with MetS. Methods: 52 individuals with MetS were considered for analysis. They were divided into two groups: aerobic interval training group (AITG; n = 26) and control group (CG; n = 26). The AITG performed 16 weeks of periodized AIT. For HRV analysis, the heart rate was recorded beat-by-beat at the beginning and the end of the AIT program and geometrical methods were used for analysis. Results: significant increase was observed for triangular index (RRtri, -1.25 ± 0.58 vs. 1.41 ± 0.57), standard deviation of distances from diagonal to points (SD1, -0.13 ± 1.52 vs. 4.34 ± 1.49), and standard deviation of distances from points to lines (SD2, -2.14 ± 3.59 vs. 11.23 ± 3.52) on AITG compared to CG. Significant differences were not observed for triangular interpolation of normal heartbeats interval histogram (TINN, -4.05 ± 17.38 vs. 25.52 ± 17.03) and SD1/SD2 ratio (0.03 ± 0.02 vs. 0.00 ± 0.02). Qualitative analysis of the Poincaré plot identified increase on dispersion of both short and long-term intervals between successive heartbeats (RR interval) on AITG after the AIT program. Conclusion: geometric indices of HRV suggest an increase in cardiac autonomic modulation in individuals with MetS after 16 weeks of periodized AIT.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Frequência Cardíaca/fisiologia , Síndrome Metabólica/fisiopatologia , Adulto , Sistema Nervoso Autônomo/fisiopatologia , Feminino , Treinamento Intervalado de Alta Intensidade , Humanos , Masculino , Síndrome Metabólica/complicações , Pessoa de Meia-Idade
3.
Medicine (Baltimore) ; 98(24): e15700, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31192910

RESUMO

INTRODUCTION: Despite the benefits, cardiovascular rehabilitation programs (CRPs) have been related to the appearance of signals and symptoms. Risk stratification protocols are commonly used to identify risks during the physical exercise; however, studies that investigate their efficacy to previse signals and symptoms are inconclusive. Furthermore, clinical, physical, and biochemical parameters have been used as risk markers for the appearance of adverse events, and to investigate their efficacy to previse signals and symptoms during the CRP sessions that could better guide the strategies adopted on these programs. OBJECTIVES: The aim of this study was to evaluate the correlations between risk stratification protocols and clinical, physical, and biochemical parameters with the appearance of signals/symptoms during CRP, as well as to evaluate if modifications on clinical, physical, and biochemical parameters could influence in the appearance of signals/symptoms during CRP. MATERIALS AND METHODS: The study was prospectively registered at ClinicalTrials.gov (NCT03446742). Forty-four patient participants of a CRP will be evaluated. First, their risk stratification is going to be performed by 2 evaluators and their clinical, physical, and biochemical parameters are going to be measured. Then, the patients are going to be followed during 24 sessions during their CRP routines in order to identify appearance of their signals/symptoms. So, the patients are going to perform their cardiovascular rehabilitation routines for 6 months and then, their clinical, physical, and biochemical parameters are going to be measured again and they are going to be followed during 24 sessions during their CRP routines in order to identify the appearance of their signals/symptoms.


Assuntos
Biomarcadores/metabolismo , Reabilitação Cardíaca/métodos , Doenças Cardiovasculares/prevenção & controle , Aptidão Cardiorrespiratória , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/fisiopatologia , Protocolos Clínicos , Feminino , Humanos , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Estudos Longitudinais , Masculino , Recuperação de Função Fisiológica , Projetos de Pesquisa , Medição de Risco , Resultado do Tratamento , Fator de Necrose Tumoral alfa/metabolismo , Teste de Caminhada
5.
Arq. bras. cardiol ; 112(5): 555-563, May 2019. tab, graf
Artigo em Inglês | LILACS-Express | ID: biblio-1011184

RESUMO

Abstract Background: The use of autonomic modulation as a predictor of cardiovascular risk in women with breast cancer is important. Objective: To evaluate the cardiac autonomic modulation of postmenopausal women using aromatase inhibitors for breast cancer treatment, as well as its relation with the following biochemical variables. Methods: Postmenopausal women who did not have breast cancer (n = 33) and postmenopausal women with breast cancer (n = 15). For evaluation of the autonomic modulation the heart rate was recorded beat-to-beat for 30 minutes and the series of RR intervals obtained were used to calculate the following heart rate variability indices: Mean RR ms, SDNN (standard deviation of all normal RR intervals, expressed in milliseconds) ms, Mean HR, RMSSD (square root of the mean of the squared differences between adjacent normal RR interval) ms, NN50 (number of pairs of successive NNs that differ by more than 50 ms) count, pNN50% (proportion of NN50 divided by total number of NNs), RRtri (RR triangular), TINN (triangular interpolation of NN interval) ms, SD1 ms, SD2 ms, LF ms2, HF ms2, LH/HF ms2. The values of biochemical variables (fasting glycemia, triglycerides, HDL-cholesterol, and C-reactive protein) were analyzed by blood sample. Results: Lower values of heart rate variability indices were observed in postmenopausal women with breast cancer in relation to postmenopausal women who did not have breast cancer: Mean RR (p = 0.03); SDNN (p = 0.03); RMSSD (p = 0.03); NN50 count (p = 0.03); pNN50 % (p = 0.03); RRtri (p = 0.02); SD1 (p = 0.01); SD2 (p = 0.02); LF ms2 (p = 0.01); HF ms2 (p = 0.03).There was an inversely proportional correlation between the indices SDNN, SD2, and HFms2 with triglycerides (SDNN p = 0.04; SD2 p = 0.04; HF ms2 p = 0.04). No statistically significant correlations were found between heart rate variability indices and others variables. Statistical significance was set at 5% for all analyses. Conclusion: Women with breast cancer present reduced autonomic modulation and in these women of heart rate variability indices are inversely correlated with triglyceride values.


Resumo Fundamentos: A modulação autonômica como um preditor de risco cardiovascular em mulheres com câncer de mama é importante. Objetivos: Avaliar a modulação autonômica em mulheres pós-menopausa em uso de inibidores de aromatase como tratamento de câncer de mama, e sua relação com algumas variáveis bioquímicas. Métodos: Foram avaliadas mulheres pós-menopausa sem câncer de mama (n = 33) e mulheres pós-menopausa com câncer de mama (n = 15). Para avaliação da modulação autonômica, a frequência cardíaca (FC) foi registrada batimento a batimento por 30 minutos, e as séries de intervalos RR obtidas foram usadas para o cálculo dos seguintes índices de variabilidade da frequência cardíaca: média de RR ms, SDNN (desvio padrão de todos os intervalos RR normais) ms, FC, RMSSD (raiz quadrada da média das diferenças ao quadrado entre os intervalos RR normais adjacentes) ms, contagem NN50 (número de pares de NNs sucessivos que se diferem em mais de 50 ms), pNN50% (proporção de NN50 dividida pelo número total de NNs), RRtri (RR triangular), TINN (interpolação triangular do intervalo NN) ms, DP1 ms, DP2 ms, LF (baixa frequência) ms2, HF (alta frequência) ms2, LH/HF ms2. Os valores das variáveis bioquímicas (glicemia de jejum, triglicerídeos, HDL-colesterol, e proteína C reativa) foram analisadas das amostras de sangue. O nível de significância adotado nas análises estatísticas foi de 5%. Resultados: As mulheres pós-menopausa com câncer de mama apresentaram menores índices de variabilidade da frequência cardíaca em comparação àquelas sem câncer de mama: média de RR (p = 0,03); SDNN (p = 0,03); RMSSD (p = 0,03); contagem NN50 (p = 0,03); pNN50% (p = 0,03); RRtri (p = 0,02), DP1 (p = 0,01), DP2 (p = 0,02); LF ms2 (p = 0,01); HF ms2 (p = -0,03). Observou-se uma correlação inversamente proporcional dos índices SDNN, DP2 e HF ms2 com triglicerídeos (SDNN p = 0,04, DP2 p = 0,04; HF ms2 0,04). Não houve correlação significativa entre os índices de variabilidade da frequência cardíaca e as demais variáveis. Conclusão: Mulheres com câncer de mama apresentam modulação autonômica diminuída e índices de variabilidade da FC inversamente correlacionados com valores de triglicerídeos.

6.
Arch. endocrinol. metab. (Online) ; 63(2): 148-156, Mar.-Apr. 2019. tab, graf
Artigo em Inglês | LILACS-Express | ID: biblio-1001218

RESUMO

ABSTRACT Objective: To evaluate the effects of 16 weeks of periodized aerobic interval training (AIT) on cardiac autonomic modulation and cardiovascular parameters of metabolic syndrome (Mets) individuals. Subjects and methods: The sample was composed of 52 subjects with a diagnosis of Mets, allocated into two groups: AIT (AITG; n = 26) and control (CG; n = 26). The AITG was submitted to a periodized AIT program, over 16 weeks, while CG was not submitted to any training program. To evaluate the autonomic modulation and cardiovascular parameters in both groups, heart rate variability (HRV) indices, blood pressure (BP), and heart rate (HR) were measured at the beginning and end of the training. Results: Statistically significant differences were not observed in HFms2 (high frequency in milisseconds), LFnu (low frequency in normality unit), HFnu (high frequency in normality unit), and LF/HF ratio indices, or in the cardiovascular parameters BP and HR when comparing the AITG with the CG. However, significant increases in rMSSD (root-means square differences of successive R-R intervals), LFms2 (low frequency in milliseconds), and SDNN (standard deviation of normal to normal intervals) were observed in the AITG. Conclusion: Periodized AIT promoted positive effects on autonomic modulation of Mets subjects, characterized by an increase in the parasympathetic, sympathetic, and global modulation of this population. Additionally, cardiovascular parameter alterations were not observed in Mets subjects submitted to periodized AIT.

7.
Arch Endocrinol Metab ; 63(2): 148-156, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30916161

RESUMO

OBJECTIVE: To evaluate the effects of 16 weeks of periodized aerobic interval training (AIT) on cardiac autonomic modulation and cardiovascular parameters of metabolic syndrome (Mets) individuals. SUBJECTS AND METHODS: The sample was composed of 52 subjects with a diagnosis of Mets, allocated into two groups: AIT (AITG; n = 26) and control (CG; n = 26). The AITG was submitted to a periodized AIT program, over 16 weeks, while CG was not submitted to any training program. To evaluate the autonomic modulation and cardiovascular parameters in both groups, heart rate variability (HRV) indices, blood pressure (BP), and heart rate (HR) were measured at the beginning and end of the training. RESULTS: Statistically significant differences were not observed in HFms2 (high frequency in milisseconds), LFnu (low frequency in normality unit), HFnu (high frequency in normality unit), and LF/HF ratio indices, or in the cardiovascular parameters BP and HR when comparing the AITG with the CG. However, significant increases in rMSSD (root-means square differences of successive R-R intervals), LFms2 (low frequency in milliseconds), and SDNN (standard deviation of normal to normal intervals) were observed in the AITG. CONCLUSION: Periodized AIT promoted positive effects on autonomic modulation of Mets subjects, characterized by an increase in the parasympathetic, sympathetic, and global modulation of this population. Additionally, cardiovascular parameter alterations were not observed in Mets subjects submitted to periodized AIT.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Exercício/fisiologia , Síndrome Metabólica/fisiopatologia , Adulto , Pressão Sanguínea/fisiologia , Terapia por Exercício/métodos , Feminino , Frequência Cardíaca/fisiologia , Treinamento Intervalado de Alta Intensidade/métodos , Humanos , Masculino , Pessoa de Meia-Idade
8.
Braz J Phys Ther ; 2019 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-30852243

RESUMO

BACKGROUND: Heart rate variability heart rate variability is used as an assessment method for cardiac autonomic modulation. Since the Task Force's publication on heart rate variability in 1996, the European Heart Rhythm Association Position Paper in 2015 and a recent publication in 2017, attention has been paid to recommendations on using heart rate variability analysis methods, as well as their applications in different physiological conditions and clinical studies. This analysis has proved to be useful as a complementary tool for clinical evaluation and to assess the effect of non-pharmacological therapeutic interventions, such as physical exercise programmes, on cardiac autonomic modulation. OBJECTIVE: The aim of this article is to make recommendations and to draw up a checklist of normalisation procedures regarding the use of heart rate variability data collection and analysis methodology, focusing on the cardiology area and cardiac rehabilitation. METHODS: Based on previous heart rate variability publications, this paper provides a description of the most common shortcomings of using th analysis methods and considers recommendations and suggestions on how to minimise these occurrences by using a specific checklist. CONCLUSIONS: This article includes recommendations and a checklist regarding the use of the heart rate variability collection and analysis methods. This work could help improve reporting on clinical evaluation and therapeutic intervention results using this method and consequently, disseminate heart rate variability knowledge.

9.
Arq Bras Cardiol ; 112(5): 555-563, 2019 05.
Artigo em Inglês, Português | MEDLINE | ID: mdl-30843932

RESUMO

BACKGROUND: The use of autonomic modulation as a predictor of cardiovascular risk in women with breast cancer is important. OBJECTIVE: To evaluate the cardiac autonomic modulation of postmenopausal women using aromatase inhibitors for breast cancer treatment, as well as its relation with the following biochemical variables. METHODS: Postmenopausal women who did not have breast cancer (n = 33) and postmenopausal women with breast cancer (n = 15). For evaluation of the autonomic modulation the heart rate was recorded beat-to-beat for 30 minutes and the series of RR intervals obtained were used to calculate the following heart rate variability indices: Mean RR ms, SDNN (standard deviation of all normal RR intervals, expressed in milliseconds) ms, Mean HR, RMSSD (square root of the mean of the squared differences between adjacent normal RR interval) ms, NN50 (number of pairs of successive NNs that differ by more than 50 ms) count, pNN50% (proportion of NN50 divided by total number of NNs), RRtri (RR triangular), TINN (triangular interpolation of NN interval) ms, SD1 ms, SD2 ms, LF ms2, HF ms2, LH/HF ms2. The values of biochemical variables (fasting glycemia, triglycerides, HDL-cholesterol, and C-reactive protein) were analyzed by blood sample. RESULTS: Lower values of heart rate variability indices were observed in postmenopausal women with breast cancer in relation to postmenopausal women who did not have breast cancer: Mean RR (p = 0.03); SDNN (p = 0.03); RMSSD (p = 0.03); NN50 count (p = 0.03); pNN50 % (p = 0.03); RRtri (p = 0.02); SD1 (p = 0.01); SD2 (p = 0.02); LF ms2 (p = 0.01); HF ms2 (p = 0.03).There was an inversely proportional correlation between the indices SDNN, SD2, and HFms2 with triglycerides (SDNN p = 0.04; SD2 p = 0.04; HF ms2 p = 0.04). No statistically significant correlations were found between heart rate variability indices and others variables. Statistical significance was set at 5% for all analyses. CONCLUSION: Women with breast cancer present reduced autonomic modulation and in these women of heart rate variability indices are inversely correlated with triglyceride values.

10.
COPD ; 15(3): 245-253, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-30375894

RESUMO

Despite the many benefits of performing physical exercise in patients with chronic obstructive pulmonary disease (COPD), information on the response of acute cardiac autonomic modulation in subjects with moderate and severe COPD during and after an aerobic exercise session at different intensities is unknown. The aim of this study was to evaluate the response of cardiac autonomic modulation in patients with moderate and severe COPD during and after an aerobic exercise session at different intensities. Twenty-seven patients with COPD, divided into: Moderate Group and Severe Group, underwent an aerobic exercise sessions with intensities equivalent to 60% and 90% of velocity corresponding to peak oxygen consumption. The heart rate variability (HRV) indices were analyzed in the time and frequency domains at the following times: at rest, during exercise, immediately after, and 5, 10, and 15 minutes after exercise. In the comparison analysis between the two groups, no differences were observed in any of the HRV indices at different intensities applied. However, it was observed that the exercise caused autonomic changes when the groups were analyzed separately. Sessions of aerobic exercise influence the autonomic modulation in patients with COPD. However, COPD severity did not influence the autonomic nervous system response to exercise and recovery moments; and there was no difference between the exercise intensities.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Exercício/fisiologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/reabilitação , Idoso , Tolerância ao Exercício/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio/fisiologia , Índice de Gravidade de Doença
11.
J Exerc Rehabil ; 14(4): 671-679, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30276192

RESUMO

The aim of this study was to verify the autonomic modulation and blood pressure after adenosine-5'-triphosphate (ATP) supplementation associated to acute aerobic exercise in hypertensive women. Eleven hypertensive women (age, 61.8±5.0 years) completed a randomized, double blind trial: ATP supplement condition (ATP=400 mg) or placebo. After 30 min of supplementation or placebo intake, the subjects performed 30 min of aerobic exercise (70%-75% of maximum heart rate). The autonomic modulation was assessed by heart rate variability during rest and recovery (postexercise until 30 min of recovery), the square root of the mean squared difference between adjacent RR intervals (RMSSD), standard deviation of successive values (SDNN), low frequency (LF) and high frequency (HF) were measured. The blood pressure (systolic blood pressure [SBP] and diastolic blood pressure, mmHg) were recorded at rest, immediately postexercise, post-10, post-20, and post-30 min after exercise. For RMSSD, there was statistically significant difference during recovery, with higher RMSSD for ATP compared to placebo (rest=16.4±8.5 vs. placebo=11.6±4.0; ATP=18.5±9.7 msec; P=0.020). When analyzing the delta (recovery minus rest), the RMSSD (ATP=2.1± 7.2 msec vs. placebo=-4.7±7.5 msec; P=0.009), LF (ATP=-19.8±122.7 vs. placebo=-94.1±200.2 msec2; P=0.02), and SDNN (ATP=-2.8±12.2 msec vs. placebo=-10.6±10.5 msec; P=0.010) were higher for ATP than placebo. Furthermore, there was a greater postexercise hypotension at 20 min for ATP (SBP: ATP=-13.2±8.4 mmHg vs. placebo=-6.1±9.9 mmHg; P=0.006). Acute ATP supplementation promoted greater postexercise hypotension for systolic blood pressure and induced faster recovery of heart rate variability in hypertensive women.

12.
Auton Neurosci ; 213: 23-33, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30005737

RESUMO

INTRODUCTION: Down syndrome (DS) results in many changes, including dysfunction in cardiac autonomic modulation. Heart rate variability (HRV) analysis evaluates the autonomic function and it is a predictor of adverse cardiovascular events. OBJECTIVE: To present results of a systematic review and a meta-analysis about heart rate variability in individuals with DS. METHOD: A systematic review was performed on PubMed, PubMed Central and Web of science databases. We included articles that exhibited all the terms: "Down Syndrome", "heart rate variability", "autonomic nervous system", "autonomic dysfunction" and "cardiac autonomic modulation". We conducted the meta-analysis to compare "DS" to "controls" during rest. Random effects models were used, as were appropriate tests for heterogeneity. RESULTS: From 271 studies, 13 were included in our review. These are conducted with volunteers from a wide age range, of either gender, and not taking medications. Meta-analysis displayed that there were no significant differences between the groups at rest, except the RMSSD, which revealed a significant (Z = -2.80, p = 0.005) main effect (Hedge's g = -0.55, 95% CI [-0.93; -0.16]), indicating difference in individuals with DS compared with controls. CONCLUSION: There is autonomic dysfunction in individuals with DS, which may or may not be expressed at rest, but it is usually demonstrated in an autonomic task. Meta-analysis specified that there was no significant alteration between DS and the controls during rest, except RMSSD index which was lower in DS than controls. PROSPERO: CRD42017068647.


Assuntos
Doenças do Sistema Nervoso Autônomo/fisiopatologia , Síndrome de Down/fisiopatologia , Frequência Cardíaca , Humanos
14.
Arq Bras Cardiol ; 111(1): 94-101, 2018 Jul.
Artigo em Inglês, Português | MEDLINE | ID: mdl-30020326

RESUMO

BACKGROUND: Type 1 diabetes mellitus can cause autonomic changes, which can be assessed by heart rate variability. Among the heart rate variability assessment methods, the symbolic analysis and Shannon entropy, based on the Chaotic dynamics, have gained prominence. OBJECTIVE: To compare heart rate variability indexes, obtained through symbolic analysis and Shannon entropy, in young adults with type 1 diabetes mellitus and healthy young individuals, associated with the analysis of linear indexes; and to verify if there are associations between the indexes obtained by the symbolic analysis and by Shannon entropy and linear indexes in diabetic individuals. METHODS: Heart rate variability data from 39 young adults with type 1 diabetes mellitus and 43 healthy young individuals were analyzed, using a cardio-frequency meter. Linear indexes (standard deviation of all normal RR intervals recorded in a time interval expressed in milliseconds; square root of the mean of the squared differences between adjacent normal RR intervals in a time interval expressed in milliseconds; low and high frequency components in millisecond squared; and normalized units and ratio between low and high frequency components) and nonlinear ones (Shannon entropy and symbolic analysis - standard without variation; with one or two variations; and with two different variations) of the heart rate variability were calculated. The statistical significance was set at 5%, and the confidence interval was 95%. RESULTS: Significantly lower values were observed in the DM1 group compared to healthy young adults for the standard deviation indexes of all normal RR intervals recorded in a time interval [37.30 (29.90) vs. 64.50 (36.20); p = 0.0001], square root of the mean of the squared differences between adjacent normal RR intervals in a time interval [32.73 (17.43) vs. 55.59 (21.60); p = 0.0001], low frequency component [402.00 (531.00) vs. 1,203.00 (1,148.00); p = 0.0001], high frequency component [386.00 (583.00) vs. 963.00 (866.00); p = 0.0001] and the pattern with two different variations [15,33 (9,22) vs. 20.24 (12.73); p = 0.0114], with the effect of this difference being considered large (standard deviation of all normal RR intervals recorded in a time interval, square root of the mean of the squared differences between adjacent normal RR intervals in a time interval and low frequency component), medium (high frequency component) and small (standard with two different variations). The agreement of the associations between the linear and non-linear indexes was considered elevated for the high frequency component index - normalized units (r = -0.776), with the standard index without variation, and moderate for the indexes square root of the mean of the squared differences between adjacent normal RR intervals in a time interval (r = 0.550), standard deviation of all normal RR intervals recorded in a time interval (r = 0.522), high frequency component - normalized units (r = 0.638) with the index standard with two similar variations, as well as for the indexes square root of the mean of the squared differences between adjacent normal RR intervals in a time interval (r = 0.627) and high frequency component - normalized units (r = 0.601) with the index standard with two different variations. CONCLUSION: Type 1 diabetes mellitus influenced linear indexes and symbolic analysis, but not yet in the complexity of heart rate variability. Additionally, heart rate variability indexes correlated with the symbolic dynamics.


Assuntos
Diabetes Mellitus Tipo 1/fisiopatologia , Frequência Cardíaca/fisiologia , Estudos de Casos e Controles , Estudos Transversais , Entropia , Feminino , Humanos , Masculino , Fatores de Tempo , Adulto Jovem
15.
Arq. bras. cardiol ; 111(1): 94-101, July 2018. tab
Artigo em Inglês | LILACS-Express | ID: biblio-950196

RESUMO

Abstract Background: Type 1 diabetes mellitus can cause autonomic changes, which can be assessed by heart rate variability. Among the heart rate variability assessment methods, the symbolic analysis and Shannon entropy, based on the Chaotic dynamics, have gained prominence. Objective: To compare heart rate variability indexes, obtained through symbolic analysis and Shannon entropy, in young adults with type 1 diabetes mellitus and healthy young individuals, associated with the analysis of linear indexes; and to verify if there are associations between the indexes obtained by the symbolic analysis and by Shannon entropy and linear indexes in diabetic individuals. Methods: Heart rate variability data from 39 young adults with type 1 diabetes mellitus and 43 healthy young individuals were analyzed, using a cardio-frequency meter. Linear indexes (standard deviation of all normal RR intervals recorded in a time interval expressed in milliseconds; square root of the mean of the squared differences between adjacent normal RR intervals in a time interval expressed in milliseconds; low and high frequency components in millisecond squared; and normalized units and ratio between low and high frequency components) and nonlinear ones (Shannon entropy and symbolic analysis - standard without variation; with one or two variations; and with two different variations) of the heart rate variability were calculated. The statistical significance was set at 5%, and the confidence interval was 95%. Results: Significantly lower values were observed in the DM1 group compared to healthy young adults for the standard deviation indexes of all normal RR intervals recorded in a time interval [37.30 (29.90) vs. 64.50 (36.20); p = 0.0001], square root of the mean of the squared differences between adjacent normal RR intervals in a time interval [32.73 (17.43) vs. 55.59 (21.60); p = 0.0001], low frequency component [402.00 (531.00) vs. 1,203.00 (1,148.00); p = 0.0001], high frequency component [386.00 (583.00) vs. 963.00 (866.00); p = 0.0001] and the pattern with two different variations [15,33 (9,22) vs. 20.24 (12.73); p = 0.0114], with the effect of this difference being considered large (standard deviation of all normal RR intervals recorded in a time interval, square root of the mean of the squared differences between adjacent normal RR intervals in a time interval and low frequency component), medium (high frequency component) and small (standard with two different variations). The agreement of the associations between the linear and non-linear indexes was considered elevated for the high frequency component index - normalized units (r = -0.776), with the standard index without variation, and moderate for the indexes square root of the mean of the squared differences between adjacent normal RR intervals in a time interval (r = 0.550), standard deviation of all normal RR intervals recorded in a time interval (r = 0.522), high frequency component - normalized units (r = 0.638) with the index standard with two similar variations, as well as for the indexes square root of the mean of the squared differences between adjacent normal RR intervals in a time interval (r = 0.627) and high frequency component - normalized units (r = 0.601) with the index standard with two different variations. Conclusion: Type 1 diabetes mellitus influenced linear indexes and symbolic analysis, but not yet in the complexity of heart rate variability. Additionally, heart rate variability indexes correlated with the symbolic dynamics.


Resumo Fundamento: O diabetes melito tipo 1 pode promover alterações autonômicas, que podem ser avaliadas pela variabilidade da frequência cardíaca. Dentre os métodos da variabilidade da frequência cardíaca, têm ganhado destaque a análise simbólica e a entropia de Shannon, baseadas na dinâmica do caos. Objetivo: Comparar índices da variabilidade da frequência cardíaca obtidos por meio da análise simbólica e da entropia de Shannon, entre jovens com diabetes melito tipo 1 e jovens saudáveis, associados à análise de índices lineares; e verificar se há associações entre os índices obtidos pela análise simbólica e pela entropia de Shannon e índices lineares em indivíduos diabéticos. Métodos: Foram analisados dados da variabilidade da frequência cardíaca de 39 jovens com diabetes melito tipo 1 e 43 jovens saudáveis, obtidos por meio de um cardiofrequencímetro. Foram calculados os índices lineares (desvio padrão de todos os intervalos RR normais gravados em um intervalo de tempo expresso em milissegundo; raiz quadrada da média do quadrado das diferenças entre intervalos RR normais adjacentes em um intervalo de tempo expresso em milissegundo; componentes de baixa e alta frequência, em milissegundo ao quadrado; e unidades normalizadas e razão entre componente de baixa e alta frequência) e não lineares (entropia de Shannon e análise simbólica - padrão sem variação; com uma ou duas variações; e com duas variações diferentes) da variabilidade da frequência cardíaca. A significância estatística adotada foi fixada em 5%, e o intervalo de confiança em 95%. Resultados: Foram observados valores significativamente menores no Grupo DM1 em comparação aos jovens saudáveis para os índices desvio padrão de todos os intervalos RR normais gravados em um intervalo de tempo [37,30 (29,90) vs. 64,50 (36,20); p = 0,0001], raiz quadrada da média do quadrado das diferenças entre intervalos RR normais adjacentes em um intervalo de tempo [32,73 (17,43) vs. 55,59 (21,60); p = 0,0001], componente de baixa frequência [402,00 (531,00) vs. 1.203,00 (1.148,00); p = 0,0001], componente de alta frequência [386,00 (583,00) vs. 963,00 (866,00); p = 0,0001] e padrão com duas variações diferentes [15,33 (9,22) vs. 20,24 (12,73); p = 0,0114], sendo o efeito desta diferença considerado grande (desvio padrão de todos os intervalos RR normais gravados em um intervalo de tempo, raiz quadrada da média do quadrado das diferenças entre intervalos RR normais adjacentes em um intervalo de tempo e componente de baixa frequência), médio (componente de alta frequência) e pequeno (padrão com duas variações diferentes). A concordância das associações entre os índices lineares e não lineares foi considerada elevada para o índice componente de alta frequência - unidades normalizadas (r = -0,776), com o índice padrão sem variação, e moderada para os índices raiz quadrada da média do quadrado das diferenças entre intervalos RR normais adjacentes em um intervalo de tempo (r = 0,550), desvio padrão de todos os intervalos RR normais gravados em um intervalo de tempo (r = 0,522), componente de alta frequência - unidades normalizadas (r = 0,638) com o índice padrão com duas variações similares, assim como para os índices raiz quadrada da média do quadrado das diferenças entre intervalos RR normais adjacentes em um intervalo de tempo (r = 0,627) e componente de alta frequência - unidades normalizadas (r = 0,601) com o índice padrão com duas variações diferentes. Conclusão: O diabetes melito tipo 1 influenciou nos índices lineares e na análise simbólica, mas ainda não na complexidade da variabilidade da frequência cardíaca. Além disso, índices de variabilidade da frequência cardíaca apresentaram correlação com a dinâmica simbólica.

17.
Clin Res Cardiol ; 107(10): 924-936, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29721647

RESUMO

AIM: To compare cardiac autonomic modulation in early- versus advanced-stage breast cancer patients before any type of cancer treatment and investigate associated factors. METHODS AND RESULTS: This cross-sectional study included women (30-69 years old) with primary diagnosis of breast cancer and women with benign breast tumors. We evaluated cardiac modulation by heart rate variability and assessed factors of anxiety, depression, physical activity, and other relevant medical variables. Patients were divided into three groups based on TNM staging of cancer severity: early-stage cancer (n = 42), advanced-stage cancer (n = 37), or benign breast tumors to serve as a control (n = 37). We analyzed heart rate variability in time and frequency domains. The advanced-stage cancer group had lower vagal modulation than early-stage and benign groups; also, the advance-stage group had lower overall heart rate variability when compared to benign conditions. Heart rate variability was influenced by age, menopausal status, and BMI. CONCLUSIONS: Heart rate variability seems to be a promising, non-invasive tool for early diagnosis of autonomic dysfunction in breast cancer and detection of cardiovascular impairments at cancer diagnosis. Cardiac autonomic modulation is inversely associated with breast cancer staging.


Assuntos
Arritmias Cardíacas/etiologia , Neoplasias da Mama/complicações , Frequência Cardíaca/fisiologia , Nervo Vago/fisiopatologia , Adulto , Idoso , Arritmias Cardíacas/fisiopatologia , Biópsia , Neoplasias da Mama/patologia , Estudos Transversais , Eletrocardiografia , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias
18.
Pediatr Cardiol ; 39(7): 1397-1403, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29766226

RESUMO

A low heart rate variability (HRV) has been associated with cardiovascular risk factors in adolescents. However, no cut-off points are known for HRV parameters in this age group, making it difficult to use in clinical practice. Thus, the aims of the current study were to establish cutoffs of HRV parameters and to examine their association with cardiovascular risk in Brazilian adolescents male. For this reason, this cross-sectional study included 1152 adolescent boys (16.6 ± 1.2 years old). HRV measures of time (SD of all RR intervals, root mean square of the squared differences between adjacent normal RR intervals, and the percentage of adjacent intervals over 50 ms), frequency domains [low (LF) and high (HF) frequency], and Poincaré plot (SD1, SD2 and SD1/SD2 ratio) were assessed. Cardiovascular risk was assessed by sum of abdominal obesity, high blood pressure, overweight, and low physical activity level. The proposed cutoffs showed moderate to high sensitivity, specificity, and area under curve values (p < 0.05). HRV frequency parameters were statistically superior when compared to time-domain and Poincaré plot parameters. The binary logistic regression analysis indicated that all proposed HRV cutoffs were independently associated with a clustering of cardiovascular risk factors, with greater magnitude of HF and SD1/SD2 ratio (two or more risk factors: OR = 3.59 and 95% CI 1.76-7.34). In conclusion, proposed HRV cutoffs have moderate to high sensitivity in detecting of the cardiovascular risk factor and HRV frequency-domain were better discriminants of cardiovascular risk than time-domain and Poincaré plot parameters.


Assuntos
Doenças Cardiovasculares/etiologia , Frequência Cardíaca/fisiologia , Medição de Risco/métodos , Adolescente , Área Sob a Curva , Brasil , Estudos Transversais , Humanos , Masculino , Fatores de Risco , Sensibilidade e Especificidade , Adulto Jovem
19.
Pediatr Cardiol ; 39(5): 869-883, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29696428

RESUMO

Duchenne muscular dystrophy (DMD) is a genetic recessive disorder with progressive muscle weakness. Despite the general muscle wasting, degeneration and necrosis of cardiomyocytes have been the main causes of morbidity and death in individuals with DMD. Cardiac failure is generally preceded by disturbances in heart rate variability (HRV), and non-invasive measurement of the autonomic nervous system has been an important tool to predict adverse cardiovascular events. Hence, the application of HRV to study autonomic modulation in DMD individuals, and the establishment of correlations between HRV and heart/lung diseases, age, and mortality will have the potential to improve quality of life and life expectancy of individuals with DMD. In order to evaluate the state of the art in this field, we conducted a systematic search in Medline/PubMed and BVS (virtual library in health) databases. We selected 8 studies using pre-defined criteria and meta-analysis revealed decreased parasympathetic activity and increased sympathetic predominance in individuals with DMD as major observations. Moreover, there is a strong association between diminished HRV and myocardial fibrosis with DMD. These patterns are evident in patients at early-stage DMD and become more prominent as disease severity and age increase. Thus, data minning clearly indicates that HRV assessment can be used as a predictor for sudden death in individuals with DMD. The use of the HRV, which is inexpensive, ubiquitously available in clinics and hospitals, and a non-invasive analysis tool, can save lives and decrease the morbity in DMD by alerting care givers to consider autonomic nervous system intervention.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Cardiomiopatias/fisiopatologia , Frequência Cardíaca/fisiologia , Distrofia Muscular de Duchenne/fisiopatologia , Cardiomiopatias/etiologia , Progressão da Doença , Feminino , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Distrofia Muscular de Duchenne/complicações , Qualidade de Vida
20.
J Bras Pneumol ; 44(1): 24-30, 2018.
Artigo em Inglês, Português | MEDLINE | ID: mdl-29538539

RESUMO

OBJECTIVE: To evaluate autonomic modulation in individuals with COPD, compared with healthy controls, via recurrence plots (RPs) and linear heart rate variability (HRV) indices. METHODS: We analyzed data on 74 volunteers, who were divided into two groups: COPD (n = 43) and control (n = 31). For calculation of HRV indices, heart rate was measured beat-by-beat during 30 min of supine rest using a heart-rate meter. We analyzed linear indices in the time and frequency domains, as well as indices derived from the RPs. RESULTS: In comparison with the control group, the COPD group showed significant increases in the indices derived from the RPs, as well as significant reductions in the linear indices in the time and frequency domains. No significant differences were observed in the linear indices in the frequency domains expressed in normalized units or in the low frequency/high frequency ratio. CONCLUSIONS: Individuals with COPD show a reduction in both sympathetic and parasympathetic activity, associated with decreased complexity of autonomic nervous system function, as identified by RPs, which provide important complementary information in the detection of autonomic changes in this population.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Frequência Cardíaca/fisiologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Volume Expiratório Forçado/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Valores de Referência , Espirometria , Estatísticas não Paramétricas , Fatores de Tempo , Capacidade Vital/fisiologia
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