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- ItemSomente MetadadadosAnalysis of cardiac autonomic modulation of children with attention deficit hyperactivity disorder(Dove Medical Press Ltd, 2014-01-01) Carvalho, Tatiana Dias de [UNIFESP]; Wajnsztejn, Rubens; Abreu, Luiz Carlos de; Vanderlei, Luiz Carlos Marques; Godoy, Moacir Fernandes; Adami, Fernando; Valenti, Vitor Engrácia [UNIFESP]; Monteiro, Carlos B. M.; Leone, Claudio; Martins, Karen Cristina da Cruz; Ferreira, Celso [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); FMABC; Univ Estadual Paulista; Universidade de São Paulo (USP)Background: Attention deficit hyperactivity disorder (ADHD) is characterized by decreased attention span, impulsiveness, and hyperactivity. Autonomic nervous system imbalance was previously described in this population. We aim to compare the autonomic function of children with ADHD and controls by analyzing heart rate variability (HRV).Methods: Children rested in supine position with spontaneous breathing for 20 minutes. Heart rate was recorded beat by beat. HRV analysis was performed in the time and frequency domains and Poincare plot.Results: Twenty-eight children with ADHD (22 boys, aged 9.964 years) and 28 controls (15 boys, age 9.857 years) participated in this study. It was determined that the mean and standard deviation of indexes which indicate parasympathetic activity is higher in children with ADHD than in children without the disorder: high frequency in normalized units, 46.182 (14.159) versus 40.632 (12.247); root mean square of successive differences, 41.821 (17.834) versus 38.150 (18.357); differences between adjacent normal-to-normal intervals greater than 50 milliseconds, 199.75 (144.00) versus 127.46 (102.21) (P<0.05); percentage of differences between adjacent normal-to-normal intervals greater than 50 milliseconds, 23.957 (17.316) versus 16.211 (13.215); standard deviation of instantaneous beat-to-beat interval, 29.586 (12.622) versus 26.989 (12.983).Conclusion: Comparison of the autonomic function by analyzing HRV suggests an increase in the activity of the parasympathetic autonomic nervous systems in children with ADHD in relation to the control group.
- ItemSomente MetadadadosAnalysis of heart rate variability in individuals subjected to different positive end expiratory pressure levels using expiratory positive airway pressure(Termedia Publishing House Ltd, 2013-08-01) Pinto, Thiago Lorentz; Sampaio, Luciana Maria Malosa; Costa, Ivan Peres; Kawaguchi, Leandro Yukio Alves; Carvalho, Flavio Aimbire Soares de [UNIFESP]; Carvalho, Regiane Albertini de; Nove de Julho Univ; Universidade Federal de São Paulo (UNIFESP)Introduction: the increase in the number of studies has led to greater security in the application of this method and the determination of its effectiveness in adults.. the purpose of the present study was to evaluate heart rate variability in healthy individuals submitted to different levels of positive expiratory pressure using an expiratory positive airway pressure (EPAP) device.Material and methods: the study involved 27 healthy male individuals ranging in age from 20 to 35 years. Patient histories were taken and the subjects were submitted to a physical examination. the volunteers were monitored using the Polar 810s (R) and submitted to the EPAP experiment. Analyses were performed on variables of the frequency domain. Sympathetic and parasympathetic bands and their relationship with sympathovagal response were also analyzed.Results: the mean value of this variable was 526.89 (55.50) ms(2) in the first period, 2811.0 (721.10) ms(2) in the fourth period and 726.52 (123.41) ms(2) in the fifth period. Regarding the parasympathetic area, significant differences were detected when Periods 1 and 5 (no load) were compared with periods in which the individuals were subjected to the use of the therapy. Sympathetic and parasympathetic areas together, a significant difference was detected regarding the sympathetic/parasympathetic ratio in the comparison between Periods 1 and 4 (p < 0.01) as well as Periods 2 and 4 (p < 0.05).Conclusions: the findings of the present study suggest that the therapeutic use of EPAP significantly alters the parameters of heart rate variability in the frequency domain, highlighting the importance of monitoring and care during the practice of EPAP.
- ItemAcesso aberto (Open Access)Arg16Gly and Gln27Glu beta 2 adrenergic polymorphisms influence cardiac autonomic modulation and baroreflex sensitivity in healthy young Brazilians(E-century Publishing Corp, 2015-01-01) Atala, Magda M.; Goulart, Alessandra [UNIFESP]; Guerra, Grazia Maria; Mostarda, Cristiano [UNIFESP]; Rodrigues, Bruno; Mello, Priscila R.; Casarine, Dulce Elena [UNIFESP]; Irigoyen, Maria Claudia [UNIFESP]; Pereira, Alexandre C.; Consolim-Colombo, Fernanda Marciano; Universidade de São Paulo (USP); Universidade Federal de São Paulo (UNIFESP); Univ Fed Maranhao; Univ Sao Judas Tadeu; Univ Nove de Julho UNINOVEThe association between functional beta(2) adrenergic receptor (beta(2)-AR) polymorphisms and cardiac autonomic modulation is still unclear. Thus, two common polymorphisms in the beta(2)-AR gene (Gln27Glu beta(2) and Arg16Gly beta(2)) were studied to determine whether they might affect tonic and reflex cardiac sympathetic activity in healthy young subjects. A total of 213 healthy young white subjects of both genders (53% female), aged 18-30 years (23.5 +/- 3.4 y), had their continuous blood pressure curves noninvasively recorded by Finometer at baseline, and other hemodynamic parameters, as cardiac autonomic modulation, baroreflex sensitivity, and allele, genotype, and diplotype frequencies calculated. Associations were made between Arg16Gly beta(2) and Gln27Glu beta(2) polymorphisms and between beta(2)-AR diplotypes and all variables. The heart rate was significantly lower (P<0.001) in the presence of homozygous Arg/Arg alleles (60.9 +/- 1.5 bpm) than in that of Arg/Gly heterozygotes (65.9 +/- 1.0 bpm) or Gly/Gly homozygotes (66.3 +/- 1.2 bpm). Homozygous carriers of Arg16 allele had an alpha index (19.2 +/- 1.3) significantly higher (P<0.001) than that of the subjects with the Gly allele Gly/Gly ( 14.5 +/- 0.7) or Arg/Gly (14.6 +/- 0.7). Furthermore, the recessive Glu27Glu and the heterozygous Gln27Glu genotypes had a higher percentage of low-frequency components (LF%) than the homozygous Gln27Gln (15.1% vs. 16.0% vs. 8.2%, P=0.03, respectively). In healthy young subjects, the presence of beta(2)-AR Arg16 allele in a recessive model was associated with higher baroreflex sensitivity, and increased parasympathetic modulation in studied individuals.
- ItemSomente MetadadadosAssociation between severity of hypoglycemia and loss of heart rate variability in patients with type 1 diabetes mellitus(Wiley, 2017) Silva, Ticiana Paes [UNIFESP]; Rolim, Luiz Clemente [UNIFESP]; Sallum Filho, Celso [UNIFESP]; Zimmermann, Livia M. [UNIFESP]; Malerbi, Fernando [UNIFESP]; Dib, Sergio Atala [UNIFESP]Background The occurrence of hypoglycemia has been associated with the presence of cardiovascular autonomic neuropathy. Cardiovascular autonomic reflex tests are the gold standard diagnostic method for cardiovascular autonomic neuropathy. Nevertheless, impaired heart rate variability indices on spectral analysis have been reported before cardiovascular autonomic reflex test abnormalities arise. The objective of the present study was to analyse the association between the severity of hypoglycemia and indices of heart rate variability on spectral analysis. Methods Consecutive type 1 diabetes patients were prospectively enrolled. Heart rate variability indices were assessed by spectral analysis. One abnormal test result was used to define impaired spectral analysis. The severity of hypoglycemia was evaluated by a hypoglycemia score and patients were classified into absent/minor or moderate/severe hypoglycemia groups. Results Patients with moderate/severe hypoglycemia were older, had longer duration of diabetes and had higher rates of diabetic complications. After adjusting for baseline clinical characteristics, impaired spectral analysis (OR: 3.85
- ItemSomente MetadadadosCardiovascular and metabolic risk markers are related to parasympathetic indices in pre-pubertal adolescents(Cambridge Univ Press, 2016) Cayres, Suziane U.; Vanderlei, Luiz Carlos M.; Silva, Danilo R. P.; Lima, Manoel Carlos S.; Barbosa, Mauricio F. [UNIFESP]; Fernandes, Romulo A.Objective To analyse the relationship between different heart rate variability indices, resting heart rate, and cardiovascular markers in adolescents. Methods A cross-sectional study was carried out with information from an ongoing cohort study. The sample was composed of 99 adolescents who complied with the following inclusion criteria: aged between 11 and 14 years; enrolled in a school unit of elementary education; absence of any known diseases; no drug consumption; and a formal consent signed by the parents or legal guardians. Weight, height, heart rate variability, lipid profile, inflammatory markers, blood pressure, resting heart rate, intima-media thickness, blood flow, and trunk fatness were measured. Partial correlation and linear regression (expressed by and 95% confidence intervals [95%CI]) analyses were used to analyse the relationships between the variables. Results In the linear regression analysis, even after adjustments for sex, age, trunk fatness, and somatic maturation, parasympathetic activity presented significant correlations with maximum carotid artery blood flow (=-0.111 [95%CI=-0.216; -0.007]), systolic blood pressure (=-0.319 [95%CI=-0.638; -0.001]), and resting heat rate (=-0.005 [95%CI=-0.009; -0.002]). Conclusion Parasympathetic activity at rest is inversely related to maximum and minimum blood flow, triacylglycerol levels, and systolic blood pressure. These findings suggest that heart rate variability has the potential to discriminate pre-pubertal adolescents at increased risk.
- ItemSomente MetadadadosCardiovascular and metabolic risk markers are related to parasympathetic indices in pre-pubertal adolescents(Cambridge Univ Press, 2016) Cayres, Suziane U.; Vanderlei, Luiz Carlos M.; Silva, Danilo R. P.; Lima, Manoel Carlos S.; Barbosa, Mauricio F. [UNIFESP]; Fernandes, Romulo A.Objective To analyse the relationship between different heart rate variability indices, resting heart rate, and cardiovascular markers in adolescents. Methods A cross-sectional study was carried out with information from an ongoing cohort study. The sample was composed of 99 adolescents who complied with the following inclusion criteria: aged between 11 and 14 years; enrolled in a school unit of elementary education; absence of any known diseases; no drug consumption; and a formal consent signed by the parents or legal guardians. Weight, height, heart rate variability, lipid profile, inflammatory markers, blood pressure, resting heart rate, intima-media thickness, blood flow, and trunk fatness were measured. Partial correlation and linear regression (expressed by and 95% confidence intervals [95%CI]) analyses were used to analyse the relationships between the variables. Results In the linear regression analysis, even after adjustments for sex, age, trunk fatness, and somatic maturation, parasympathetic activity presented significant correlations with maximum carotid artery blood flow (=-0.111 [95%CI=-0.216; -0.007]), systolic blood pressure (=-0.319 [95%CI=-0.638; -0.001]), and resting heat rate (=-0.005 [95%CI=-0.009; -0.002]). Conclusion Parasympathetic activity at rest is inversely related to maximum and minimum blood flow, triacylglycerol levels, and systolic blood pressure. These findings suggest that heart rate variability has the potential to discriminate pre-pubertal adolescents at increased risk.
- ItemSomente MetadadadosComparison of the Effects of Hydration with Water or Isotonic Solution on the Recovery of Cardiac Autonomic Modulation(Human Kinetics Publ Inc, 2015-04-01) Vanderlei, Franciele Marques [UNIFESP]; Moreno, Isadora Lessa [UNIFESP]; Marques Vanderlei, Luiz Carlos; Pastre, Carlos Marcelo; Abreu, Luiz Carlos de [UNIFESP]; Ferreira, Celso [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); São Paulo State UnivDespite the importance of hydration during exercise, the impact of ingesting water or isotonic solution during and after exercise on the regulation of autonomic modulation is unclear. the study aimed to compare the effect of ingesting water or isotonic solution (Gatorade (R), Brazil) on cardiac autonomic modulation in young people after submaximal aerobic exercise. Thirty-one young men were subjected to a protocol consisting of 4 steps: 1) incremental test, 2) control protocol without hydration, 3) protocol with ingestion of water, and 4) protocol with ingestion of isotonic solution. the protocol consisted of 10 min of rest, 90 min of treadmill exercise at 60% VO2peak, and 60 min of recovery at rest. in the hydration protocols, hydration occurred during and after exercise, every 15 min beginning after the 15th minute of exercise, with the amount ingested proportional to body mass lost in the control protocol. Autonomic modulation was evaluated by heart rate variability. the hydration protocols promoted a more efficient recovery of autonomic modulation, and for the exercise performed, regardless of the hydration administered, the effect on autonomic modulation was similar.
- ItemAcesso aberto (Open Access)Geometric index of heart rate variability in chronic obstructive pulmonary disease(Elsevier B.V., 2011-11-01) Carvalho, Tatiana Dias de [UNIFESP]; Pastre, Carlos Marcelo; Rossi, Renata Claudino; Abreu, Luiz Carlos de; Valenti, Vitor Engrácia [UNIFESP]; Vanderlei, Luiz Carlos Marques; Univ Estadual Paulista UNESP; Universidade Federal de São Paulo (UNIFESP); Fac Med ABCBackground: It was already evidenced decreased heart rate variability (HRV) in chronic obstructive pulmonary disease (COPD) patients at rest.Objective: in order to insert new elements in the literature regarding this issue, we evaluated geometric index of HRV in COPD subjects.Method: We analyzed data from 34 volunteers, divided into two groups according to spirometric values: COPD (17 volunteers, FEV1/FVC = 47.3 +/- 10.2; FEV1 = 50.8 +/- 15.7) and control (17 volunteers, FEV1/FVC = 78.8 +/- 10.8; FEV1 = 100.1 +/- 14.7). for analysis of HRV indexes the volunteers remained in the supine position for 30 minutes. We analyzed the following indexes: triangular index (RRtri), triangular interpolation of RR intervals (TINN) and Poincare plot (SD1, SD2 and SD1/SD2). Student t test for unpaired samples and Mann-Whitney test were used for data analysis.Results: We observed statistically significant reductions in geometric indexes in the COPD group: RRtri (0.043 +/- 0.01 vs. 0.059 +/- 0.02; p = 0.018), TINN (105.88 +/- 51.82 vs. 151.47 +/- 49.9; p=0.014), SD1 (9.76 +/- 4.66 vs. 14.55 +/- 6.04; p = 0.014) and SD2 (34.86 +/- 17.02 vs. 51.51 +/- 18.38; p = 0.010). SD1/5D2 (0.30 +/- 0.11 vs. 0.28 +/- 0.07; p = 0.605) were not significantly different between groups. Patients with COPD presented a visual analysis of Poincare plot of lower dispersion of RR intervals both beat to beat and the long term.Conclusion: Subjects with COPD present reduction of geometric indexes of HRV, indicating reduced heart rate variability. (C) 2010 Sociedade Portuguesa de Pneumologia. Published by Elsevier Espana, S.L. All rights reserved.
- ItemSomente MetadadadosHeart rate variability analysis by chaotic global techniques in children with attention deficit hyperactivity disorder(Wiley-Hindawi, 2016) Wajnsztejn, Rubens; De Carvalho, Tatiana Dias [UNIFESP]; Garner, David M.; Marques Vanderlei, Luiz Carlos; Godoy, Moacir Fernandes; Raimundo, Rodrigo Daminello; Ferreira, Celso; Valenti, Vitor E.; De Abreu, Luiz CarlosAttention deficit hyperactivity disorder (ADHD) is characterized by decreased attention span, impulsiveness, and hyperactivity. Autonomic nervous system imbalance was previously described in this population. We aim to compare the autonomic function of children with ADHD and controls by analyzing heart rate variability (HRV). Children with ADHD (22 boys, mean age 9.964 years) and 28 controls (15 boys, mean age 9.857 years) rested in supine position with spontaneous breathing for 20min. Heart rate was recorded beat by beat. HRV analysis was performed by use of chaotic global techniques. ADHD promoted an increase in the chaotic forward parameter. The algorithm which applied all three chaotic global parameters was only the second optimum statistically measured by Kruskal-Wallis (P <0.0001) and low standard deviations. It was also highly influential by principal component analysis with almost all variation covered by the first two components. The third algorithm which lacked the (high spectral Detrended Fluctuation Analysis) parameter performed best statistically. However, we chose the algorithm which applied all three chaotic globals due to previous studies mentioned in the textforward and inverse problems. Comparison of the autonomic function by analyzing HRV with chaotic global techniques suggests an increase in chaotic activity in children with ADHD in relation to the control group. (c) 2015 Wiley Periodicals, Inc. Complexity 21: 412-419, 2016
- ItemAcesso aberto (Open Access)Heart rate variability in normal and pathological sleep(Frontiers Research Foundation, 2013-01-01) Tobaldini, Eleonora; Nobili, Lino; Strada, Silvia; Casali, Karina Rabello [UNIFESP]; Braghiroli, Alberto; Montano, Nicola; Univ Milan; Osped Niguarda Ca Granda; Universidade Federal de São Paulo (UNIFESP); Univ Fdn Cardiol; Fdn S Maugeri; St Annes Univ HospSleep is a physiological process involving different biological systems, from molecular to organ level; its integrity is essential for maintaining health and homeostasis in human beings. Although in the past sleep has been considered a state of quiet, experimental and clinical evidences suggest a noteworthy activation of different biological systems during sleep. A key role is played by the autonomic nervous system (ANS), whose modulation regulates cardiovascular functions during sleep onset and different sleep stages. Therefore, an interest on the evaluation of autonomic cardiovascular control in health and disease is growing by means of linear and non-linear heart rate variability (HRV) analyses. the application of classical tools for ANS analysis, such as HRV during physiological sleep, showed that the rapid eye movement (REM) stage is characterized by a likely sympathetic predominance associated with a vagal withdrawal, while the opposite trend is observed during non-REM sleep. More recently, the use of non-linear tools, such as entropy-derived indices, have provided new insight on the cardiac autonomic regulation, revealing for instance changes in the cardiovascular complexity during REM sleep, supporting the hypothesis of a reduced capability of the cardiovascular system to deal with stress challenges. Interestingly, different HRV tools have been applied to characterize autonomic cardiac control in different pathological conditions, from neurological sleep disorders to sleep disordered breathing (SDB). in summary, linear and non-linear analysis of HRV are reliable approaches to assess changes of autonomic cardiac modulation during sleep both in health and diseases. the use of these tools could provide important information of clinical and prognostic relevance.
- ItemSomente MetadadadosImproved cardiovascular autonomic modulation in transgenic rats expressing an Ang-(1-7)-producing fusion protein(Canadian Science Publishing, Nrc Research Press, 2017) Dartora, Daniela Ravizzoni; Irigoyen, Maria-Claudia; Casali, Karina Rabello [UNIFESP]; Moraes-Silva, Ivana C.; Bertagnolli, Mariane; Bader, Michael; Santos, Robson A. S.Angiotensin-(1-7) counterbalances angiotensin II cardiovascular effects. However, it has yet to be determined how cardiovascular autonomic modulation may be affected by chronic and acute elevation of Ang-(1-7). Hemodynamics and cardiovascular autonomic profile were evaluated in male Sprague-Dawley (SD) rats and transgenic rats (TGR) overexpressing Ang-(1-7) [TGR(A1-7) 3292]. Blood pressure (BP) was directly measured while cardiovascular autonomic modulation was evaluated by spectral analysis. TGR received A-779 or vehicle and SD rats received Ang-(1-7) or vehicle and were monitored for 5 h after i.v. administration. In another set of experiments with TGR, A-779 was infused for 7 days using osmotic mini pumps. Although at baseline no differences were observed, acute administration of A-779 in TGR produced a marked long-lasting increase in BP accompanied by increased BP variability (BPV) and sympathetic modulation to the vessels. Likewise, chronic administration of A-779 with osmotic mini pumps in TGR increased heart rate, sympathovagal balance, BPV, and sympathetic modulation to the vessels. Administration of Ang-(1-7) to SD rats increased heart rate variability values in 88% accompanied by 8% of vagal modulation increase and 18% of mean BP reduction. These results show that both acute and chronic alteration in the Ang-(1-7)-Mas receptor axis may lead to important changes in the autonomic control of circulation, impacting either sympathetic and (or) parasympathetic systems.
- ItemAcesso aberto (Open Access)Increased vascular sympathetic modulation in mice with Mas receptor deficiency(Sage Publications Ltd, 2016) Casali, Karina Rabello [UNIFESP]; Dartora, Daniela Ravizzoni; Moura, Marina; Bertagnolli, Mariane; Bader, Michael [UNIFESP]; Haibara, Andrea; Alenina, Natalia; Irigoyen, Maria Claudia [UNIFESP]; Santos, Robson A.Introduction: The angiotensin-converting enzyme 2 (ACE2)/angiotensin (Ang)-(1-7)/Mas axis could modulate the heart rate (HR) and blood pressure variabilities (BPV) which are important predictors of cardiovascular risk and provide information about the autonomic modulation of the cardiovascular system. Therefore we investigated the effect of Mas deficiency on autonomic modulation in wild type and Mas-knockout (KO) mice. Methods: Blood pressure was recorded at high sample rate (4000 Hz). Stationary sequences of 200-250 beats were randomly chosen. Frequency domain analysis of HR and BPV was performed with an autoregressive algorithm on the pulse interval sequences and on respective systolic sequences. Results: The KO group presented an increase of systolic arterial pressure (SAP
- ItemAcesso aberto (Open Access)Measurement of Mouse Heart Rate Variability using Echocardiographic System(Medknow Publications & Media Pvt Ltd, 2018) Stoyell-Conti, Filipe Fernandes; Santos, Fernando; Machi, Jacqueline Freire; Hernandez, Diana Rosa; Barboza, Catarina Andrade; Irigoyen, Maria-Claudia [UNIFESP]; De Angelis, Katia [UNIFESP]; Morris, MarianaAim: We employed an echocardiographic (ECHO) system as the backbone for the collection of electrocardiogram (ECG) and heart rate variability (HRV) data. The system was tested using an exercise model in which C57 male mice were exposed to sham or forced wheel running. Methods: Peak/peak (RR) interval was recorded over a 3 min period using the ECG platform of the ECHO system. Isoflurane-anesthetized male mice were divided into two groups (n = 8/group): sedentary (S) and forced wheel trained (T). HRV was analyzed in time and frequency domains (Fast Fourier Transform). Exercise training (T) was performed on a motorized wheel at low intensity 1 h/day, 5 days/week, 8 weeks duration. Cardiac morphometry and function were analyzed using ECHO while ECG was the basis to measure HRV. The sampling rate was 8000 Hz. Results show that the trained mice presented a reduction in heart rate as compared to the sedentary group. This was associated with lower cardiac sympathetic and higher parasympathetic modulation leading to an improved sympathetic/parasympathetic ratio (low-frequency band/high-frequency band). The trained group showed a reduction in isovolumetric relaxation time, reduced myocardial performance index, increased relative wall thickness, and left ventricle mass when compared to the sedentary group. Conclusion: Results document the utility of combining the ECHO and the ECG platform, allowing for the dual measurement of autonomic and cardiac function in mice.
- ItemSomente MetadadadosModulação autonômica e índice de massa corporal de crianças com síndrome de down(Universidade Federal de São Paulo (UNIFESP), 2014-12-03) Carvalho, Datiana Dias de [UNIFESP]; Ferreira, Celso Ferreira [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)The aim of this study is to analyze the autonomic modulation in children with Down syndrome (DS). The study was conducted with a convenience sample of children with DS and without heart disease, from the Genetics Clinic of the Hospital Infantil Darcy Vargas and APAE São Paulo, São Paulo, SP, Brazil. The control group was matched for sex and age. The analysis of autonomic modulation was performed using the indices of heart rate variability (HRV). The children remained in the supine position with spontaneous breathing for 20 min. Heart rate was recorded beat-to-beat. HRV analysis was performed in time and frequency domain. For data analysis, we used Student's t test: unpaired and Mann-Whitney. It was considered statistically significant at p < 0.05. From 75 children with DS, 50 were excluded, a total of 25 children [16 boys, 8.6 (1.4) years] participated in this study, and the control group also consisted of 25 children [16 boys, 9.0 (1.2) years] without the syndrome. The BMI of the volunteers with DS was higher than the controls [19.1 (2.9) vs. 15.8 (1.2), p < 0.0001]. There were differences between groups in the indices in frequency domain: LFms2 [1242.1 (788.25) vs. 786.44 (481.90), p = 0.040], LFun [69.104 (11.247) vs. 57.348 (11.683), p = 0.0004], HFun [30.896 (11.247) vs. 42.520 (11.634), p = 0.0004] and LF/HF [2.594 (1.104) vs. 1.579 (0.9982), p = 0.0004]. No differences were observed in time domain indices. The results indicate increased indices representing the sympathetic branch of the autonomic nervous system and those that indicate the overall modulation in children with DS.
- ItemAcesso aberto (Open Access)Neuropatia autonômica cardiovascular diabética: fatores de risco, impacto clínico e diagnóstico precoce(Sociedade Brasileira de Cardiologia - SBC, 2008-04-01) Rolim, Luiz Clemente de Souza Pereira [UNIFESP]; Sá, João Roberto de [UNIFESP]; Chacra, Antonio Roberto [UNIFESP]; Dib, Sergio Atala [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Cardiovascular autonomic neuropathy (CAN) is one of the most clinically significant complications of diabetes mellitus (DM), but one of the least frequently diagnosed. In this review, we discuss the major risk factors for the development and progression of CAN in patients with DM, the natural history of autonomic neuropathy and its impact on cardiovascular disease in DM, as well as the tests for the early diagnosis and staging of CAN in the clinical practice. The bibliographic research was based on two databases: Medline and Tripdatabase, with the following descriptors: diabetic cardiovascular autonomic neuropathy and cardiovascular autonomic neuropathy and diabetes. We selected English and German articles, written between 1998 and 2007. In its initial stages (early and intermediate), CAN may be diagnosed and reversed. However, in advanced cases (severe stage), the only treatment that remains is a symptomatic one. CAN is associated with higher cardiovascular morbidity and mortality rates and poor quality of life in diabetic individuals.
- ItemSomente MetadadadosA Simple Approach to Assess VT During a Field Walk Test(Georg Thieme Verlag Kg, 2010-10-01) Dourado, Victor Zuniga [UNIFESP]; Banov, M. C.; Marino, M. C. [UNIFESP]; Souza, V. L. de [UNIFESP]; Antunes, L. C. de O.; McBurnie, M. A.; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP); Kaiser Permanente Ctr Hlth ResWe aimed to examine whether the ventilatory threshold (VT) during an incremental shuttle walk test (ISWT) could be determined using heart rate variability (HRV) analysis. Further aims were to assess variables capable of predicting performance in the ISWT and the intensity of this test. Beat-to-beat RR intervals and gas exchange values in 10 healthy subjects (31-83 years; 7 men) were collected during the ISWT. the ventilatory equivalent was used to assess VT from respiratory components. To determine the HRV threshold (HRVT), the instantaneous beat-to-beat variability values of the RR intervals at each stage of exercise were graphically plotted against walking speed (WS). the oxygen consumption at HRVT was calculated (VO(2)HRVT). No significant differences were found between walking speed (WS) at VT and WS at HRVT (5.04 +/- 1.00 vs. 5.10 +/- 1.04 km/h; p = 0.89). Linear regression analysis revealed a strong correlation between VO(2)VT and VO(2)HRVT (r(2) = 0.896). the Bland and Altman plot analysis revealed an agreement between VO(2)VT and VO(2)HRVT (-0.05; 95 % CI: -0.30-0.20 L/min). Thus, the VT can be assessed during the ISWT using a simple heart monitor. the ISWT may be a useful tool to assess exercise capacity and prescribe walking programs.