Papers by Aparecida Catai
American journal of physiology. Regulatory, integrative and comparative physiology, Jan 22, 2015
The cardiovascular autonomic control and the baroreflex sensitivity (BRS) have been widely studie... more The cardiovascular autonomic control and the baroreflex sensitivity (BRS) have been widely studied in FMS patients through the computation of linear indices of spontaneous heart period (HP) and systolic arterial pressure (SAP) variabilities. However, there are many methodological difficulties regarding the quantification of BRS by the traditional indices especially in relation to the issue of causality. This difficulty has been directly tackled via a model-based approach describing the closed loop HP-SAP interactions and the exogenous influences of respiration. Therefore, we aimed to assess if the BRS assessed by the model-based causal closed-loop approach during supine and active standing in patients with FMS could provide complementary information to those obtained by traditional indices based on time and frequency domains. The findings of this study revealed that, although the traditional methods to quantify BRS did not show any significant differences between groups, the causali...
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Arquivos Brasileiros de Cardiologia, 2015
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Clinical and experimental rheumatology
To evaluate the effects of a hydrotherapy programme on aerobic capacity and linear and non-linear... more To evaluate the effects of a hydrotherapy programme on aerobic capacity and linear and non-linear dynamics of heart rate variability (HRV) in women with fibromyalgia syndrome (FMS). 20 women with FMS and 20 healthy controls (HC) took part in the study. The FMS group was evaluated at baseline and after a 16-week hydrotherapy programme. All participants underwent cardiopulmonary exercise testing on a cycle ergometer and RR intervals recording in supine and standing positions. The HRV was analysed by linear and non-linear methods. The current level of pain, the tender points, the pressure pain threshold and the impact of FMS on quality of life were assessed. The FMS patients presented higher cardiac sympathetic modulation, lower vagal modulation and lower complexity of HRV in supine position than the HC. Only the HC decreased the complexity indices of HRV during orthostatic stimulus. After a 16-week hydrotherapy programme, the FMS patients increased aerobic capacity, decreased cardiac ...
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Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference, 2011
We checked whether the observed shift of the dominant causality from heart period (HP) to systoli... more We checked whether the observed shift of the dominant causality from heart period (HP) to systolic arterial pressure (SAP) in supine position to the reverse causal direction in upright position could be the result of the exogenous action of respiration on both variables. A model-based approach exploiting a multivariate dynamic adjustment class was utilized to decompose HP and SAP dynamics into partial processes and cancel respiratory-related influences from HP and SAP series. Causality was assessed in the information domain through a bivariate approach based on cross-conditional entropy. After canceling respiratory-related influences we observed the same trend on causality from supine to upright position as detected from the original series, thus suggesting that respiratory influences are not responsible per se for HP-SAP causal relations.
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Frontiers in Physiology, 2015
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The application of continuous positive airway pressure (CPAP) produces important hemodynamic alte... more The application of continuous positive airway pressure (CPAP) produces important hemodynamic alterations, which can influence breathing pattern (BP) and heart rate variability (HRV). The aim of this study was to evaluate the effects of different levels of CPAP on postoperative BP and HRV after coronary artery bypass grafting (CABG) surgery and the impact of CABG surgery on these variables. Eighteen patients undergoing CABG were evaluated postoperatively during spontaneous breathing (SB) and application of four levels of CPAP applied in random order: sham (3 cmH₂O), 5 cmH₂O, 8 cmH₂O, and 12 cmH₂O. HRV was analyzed in time and frequency domains and by nonlinear methods and BP was analyzed in different variables (breathing frequency, inspiratory tidal volume, inspiratory and expiratory time, total breath time, fractional inspiratory time, percent rib cage inspiratory contribution to tidal volume, phase relation during inspiration, phase relation during expiration). There was significant postoperative impairment in HRV and BP after CABG surgery compared to the preoperative period and improvement of DFAα1, DFAα2 and SD2 indexes, and ventilatory variables during postoperative CPAP application, with a greater effect when 8 and 12 cmH₂O were applied. A positive correlation (P < 0.05 and r = 0.64; Spearman) was found between DFAα1 and inspiratory time to the delta of 12 cmH₂O and SB of HRV and respiratory values. Acute application of CPAP was able to alter cardiac autonomic nervous system control and BP of patients undergoing CABG surgery and 8 and 12 cmH₂O of CPAP provided the best performance of pulmonary and cardiac autonomic functions.
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Entropy, 2014
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Brazilian journal of physical therapy
Reduced respiratory muscle endurance (RME) contributes to increased dyspnea upon exertion in pati... more Reduced respiratory muscle endurance (RME) contributes to increased dyspnea upon exertion in patients with cardiovascular disease. The objective was to characterize ventilatory and metabolic responses during RME tests in post-myocardial infarction patients without respiratory muscle weakness. Twenty-nine subjects were allocated into three groups: recent myocardial infarction group (RG, n=9), less-recent myocardial infarction group (LRG, n=10), and control group (CG, n=10). They underwent two RME tests (incremental and constant pressure) with ventilatory and metabolic analyses. One-way ANOVA and repeated measures one-way ANOVA, both with Tukey post-hoc, were used between groups and within subjects, respectively. Patients from the RG and LRG presented lower metabolic equivalent and ventilatory efficiency than the CG on the second (50± 06, 50± 5 vs. 42± 4) and third part (50± 11, 51± 10 vs. 43± 3) of the constant pressure RME test and lower metabolic equivalent during the incremental p...
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Brazilian Journal of Physical Therapy, 2014
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Brazilian Journal of Physical Therapy, 2013
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Brazilian journal of physical therapy
Chronic heart failure (CHF) leads to exercise intolerance. However, non-invasive ventilation is a... more Chronic heart failure (CHF) leads to exercise intolerance. However, non-invasive ventilation is able to improve functional capacity of patients with CHF. The aim of this study was to evaluate the effectiveness of continuous positive airway pressure (CPAP) on physical exercise tolerance and heart rate variability (HRV) in patients with CHF. Method : Seven men with CHF (62 ± 8 years) and left ventricle ejection fraction of 41 ± 8% were submitted to an incremental symptom-limited exercise test (IT) on the cicloergometer. On separate days, patients were randomized to perform four constant work rate exercise tests to maximal tolerance with and without CPAP (5 cmH2O) in the following conditions: i) at 50% of peak work rate of IT; and ii) at 75% of peak work rate of IT. At rest and during these conditions, instantaneous heart rate (HR) was recorded using a cardiofrequencimeter and HRV was analyzed in time domain (SDNN and RMSSD indexes). For statistical procedures, Wilcoxon test or Kruskal...
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Physiotherapy theory and practice, Jan 14, 2015
Recently, low-level laser (light) therapy (LLLT) has been used to improve muscle performance. Thi... more Recently, low-level laser (light) therapy (LLLT) has been used to improve muscle performance. This study aimed to evaluate the effectiveness of near-infrared light-emitting diode therapy (LEDT) and its mechanisms of action to improve muscle performance in an elite athlete. The kinetics of oxygen uptake (VO2), blood and urine markers of muscle damage (creatine kinase - CK and alanine) and fatigue (lactate) were analyzed. Additionally, some metabolic parameters were assessed in urine using proton nuclear magnetic resonance spectroscopy ((1)H NMR). A LED cluster with 50 LEDs (λ = 850 nm; 50 mW 15 s; 37.5 J) was applied on legs, arms and trunk muscles of a single runner athlete 5 min before a high-intense constant workload running exercise on treadmill. The athlete received either Placebo-1-LEDT; Placebo-2-LEDT; or Effective-LEDT in a randomized double-blind placebo-controlled trial with washout period of 7 d between each test. LEDT improved the speed of the muscular VO2 adaptation (∼-9...
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Objective: To evaluate heart rate variability (HRV) among elderly patients with chronic obstructi... more Objective: To evaluate heart rate variability (HRV) among elderly patients with chronic obstructive pulmonary disease (COPD) and healthy elderly individuals, during postural change. Method: Nine individuals with COPD (70 years old) and eight healthy individuals (68 years old) were studied. Heart rate and electrocardiographic R-R intervals (iR-R) were recorded for 360 seconds in the supine and seated positions. HRV was analyzed in the time domain (TD) (RMSSD index, i.e. the root mean square of the squares of the differences between successive iR-R records, and the SDNN index, i.e. the mean standard deviation of normal iR-R in ms) and in the frequency domain (FD), from the low-frequency (LF) and high-frequency (HF) bands in absolute units (au) and normalized units (nu), and the LF/HF ratio. The Mann-Whitney and Wilcoxon Tests respectively were utilized for inter-group and intra-group analysis, with a significant level of p< 0.05 (median values). Results: In TD, the control group (C...
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The European Journal of Contraception and Reproductive Health Care, 2011
To evaluate the influence of oral contraceptives (OCs) containing 20 μg ethinylestradiol (EE) and... more To evaluate the influence of oral contraceptives (OCs) containing 20 μg ethinylestradiol (EE) and 150 μg gestodene (GEST) on the autonomic modulation of heart rate (HR) in women. One-hundred and fifty-five women aged 24 ± 2 years were divided into four groups according to their physical activity and the use or not of an OC: active-OC, active-non-OC (NOC), sedentary-OC, and sedentary-NOC. The heart rate was registered in real time based on the electrocardiogram signal for 15 minutes, in the supine-position. The heart rate variability (HRV) was analysed using Shannon&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s entropy (SE), conditional entropy (complexity index [CInd] and normalised CInd [NCI]), and symbolic analysis (0V%, 1V%, 2LV%, and 2ULV%). For statistical analysis the Kruskal-Wallis test with Dunn post hoc and the Wilcoxon test (p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05 was considered significant) were applied. Treatment with this COC caused no significant changes in SE, CInd, NCI, or symbolic analysis in either active or sedentary groups. Active groups presented higher values for SE and 2ULV%, and lower values for 0V% when compared to sedentary groups (p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05). HRV patterns differed depending on life style; the non-linear method applied was highly reliable for identifying these changes. The use of OCs containing 20 μg EE and 150 μg GEST does not influence HR autonomic modulation.
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2014 8th Conference of the European Study Group on Cardiovascular Oscillations (ESGCO), 2014
ABSTRACT The aim of this study was to evaluate the relationship between Shannon entropy (SE) and ... more ABSTRACT The aim of this study was to evaluate the relationship between Shannon entropy (SE) and symbolic analysis (SA) of heart rate variability at rest in 3 groups: patients with coronary artery disease (CAD), CAD with diabetes mellitus (CAD-DM), and healthy individuals (H). We evaluated 44 men into the groups (CAD, n=16, CAD-DM, n=13 and H, n=15). The R-R intervals (R-Ri) were recorded at rest in the supine position for 15 minutes. SA analysis classified patterns of R-Ri according to the number of variations into stable and unstable patterns. Significant and negative correlation was found between SE and the percentage of stable patterns for CAD and CAD-DM. Positive correlation was found between SE and the percentage of unstable patterns in all the groups. We conclude that complexity of cardiovascular control had a positive relationship with the cardiac parasympathetic modulation in all groups and negative relationship with the sympathetic modulation in CAD and CAD-DM groups.
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Revista Brasileira de Cirurgia Cardiovascular, 2014
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2014 8th Conference of the European Study Group on Cardiovascular Oscillations (ESGCO), 2014
ABSTRACT Frailty has been described as a clinical state of vulnerability to stress, consequence f... more ABSTRACT Frailty has been described as a clinical state of vulnerability to stress, consequence from decline of resilience and physiological reserves and progressive decline on ability of homeostasis maintenance. The aim of this study was to evaluate the complexity of R-R intervals (RR) in resting supine (REST) and standing (STAND) position in 3 groups: frail, pre-frail and non-frail. Eighty older people (60-94 years old) were divided into frail group (n = 6), pre-frail (n=36) and non-frail group (n=38). The RR series were recorded at REST and during STAND for 10 minutes in each position. Short sequences of RR were analyzed by conditional entropy (CE) and approximate entropy (ApEn). Position, group and interaction effects were evaluated by two-way repeated-measures ANOVA. CE indicated only position effect while ApEn showed only group effect. ApEn seems to be more suitable for assessing changes in the complexity in frailty syndrome.
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2014 8th Conference of the European Study Group on Cardiovascular Oscillations (ESGCO), 2014
ABSTRACT Aging causes changes in cardiovascular control. The aim of the study was to analyze the ... more ABSTRACT Aging causes changes in cardiovascular control. The aim of the study was to analyze the effects of age on baroreflex sensitivity of healthy individuals of different ages, through cross-spectral analysis. One hundred and ten individuals divided into 5 age groups were evaluated. Heart period (HP) and systolic blood pressure (SBP) were derived from ECG and blood pressure signals recorded simultaneously for 15 minutes in the supine and orthostatic position. The gain of the transfer function from SBP to HP was taken as an index of baroreflex sensitivity (BRSgain) and computed in low (LF) and high frequency (HF). In both positions and in both bands, BRSgain fell with age, thus suggesting a decrease magnitude of the HP response to SAP changes with age.
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Clinics, 2009
Noninvasive positive pressure has been used to treat several diseases. However, the physiological... more Noninvasive positive pressure has been used to treat several diseases. However, the physiological response of the cardiac autonomic system during bilevel positive airway pressure (Bilevel) remains unclear. The aim of this study was to evaluate the heart rate variability (HRV) during Bilevel in young healthy subjects. Twenty men underwent 10-minute R-R interval recordings during sham ventilation (SV), Bilevel of 8-15 cmH(2)O and Bilevel of 13-20 cmH(2)O. The HRV was analyzed by means of the parallel R-R interval (mean R-Ri), the standard deviation of all R-Ri (SDNN), the root mean square of the squares of the differences between successive R-Ri (rMSSD), the number of successive R-Ri pairs that differ by more than 50 milliseconds (NN50), the percentage of successive R-Ri that differ by more than 50 milliseconds (pNN50), the low frequency (LF), the high frequency (HF) and SD1 and SD2. Additionally, physiological variables, including blood pressure, breathing frequency and end tidal CO(2), were collected. Repeated-measures ANOVA and Pearson correlation were used to assess the differences between the three studied conditions and the relationships between the delta of Bilevel at 13-20 cmH(2)O and sham ventilation of the HRV indexes and the physiological variables, respectively. The R-Ri mean, rMSSD, NN50, pNN50 and SD1 were reduced during Bilevel of 13-20 cmH(2)O as compared to SV. An R-Ri mean reduction was also observed in Bilevel of 13-20 cmH(2)O compared to 8-15 cmH(2)O. Both the R-Ri mean and HF were reduced during Bilevel of 8-15 cmH(2)O as compared to SV, while the LF increased during application of Bilevel of 8-15 cmH(2)O as compared to SV. The delta (between Bilevel at 13-20 cmH(2)O and sham ventilation) of ETCO(2) correlated positively with LF, HF, the LF/HF ratio, SDNN, rMSSD and SD1. Acute application of Bilevel was able to alter the cardiac autonomic nervous system, resulting in a reduction in parasympathetic activity and an increase in sympathetic activity and higher level of positive pressure can cause a greater influence on the cardiovascular and respiratory system.
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Revista Brasileira de Fisioterapia, 2007
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Papers by Aparecida Catai