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1.
Georgian Med News ; (294): 27-31, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31687944

RESUMO

The aim of the research is to study the dynamics of functional capabilities of 17-22 year old girls with different vegetative status during the ovarian-menstrual cycle. By the use of questionnaires and anthropo-physiometry, 28 girls with low motor activity and a regular (more than 3 cycles) menstrual cycle were selected, which allowed to determine the phases by calendar method. All of the surveyed people were in the main medical group of health. The modernized method of D. N. Davidenko muscular load was used. The heart rate was recorded at rest when the heart rate was reached at 150-155 beats per minute, at the end of testing and on the 5th minute of recovery, sitting on the cycle ergometer. To estimate the variability of the heart rate, a number of indicators proposed by R. M. Bayevsky were calculated to characterize the state of the vegetative nervous system. The degree of centralization of heart rate control was determined by means of a stress index, on the basis of which the group of patients was divided into subgroups depending on the type of regulation in the state of relative rest in the first (menstrual) phase of the menstrual cycle. It has been identified that vagotonics are characterized by higher, and sympathicotonics - by low values of PWC170, as an integral indicator of the body's functional capabilities. The optimal phases of physical performance for girls with vagotonic type of regulation are menstrual and premenstrual, with normotonic - menstrual and ovulatory, with sympathicotonic - postmenstrual and postovulatory phases of OMC. Physical activity in other phases of the cycle increases the level of functional stress and can provoke pre-pathological and pathological conditions.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Exercício/fisiologia , Frequência Cardíaca/fisiologia , Hormônios/sangue , Ciclo Menstrual/fisiologia , Ovário/fisiologia , Adolescente , Feminino , Humanos , Adulto Jovem
2.
Medicine (Baltimore) ; 98(46): e17656, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31725608

RESUMO

INTRODUCTION: People with visual impairment (VI) have loss of vision that causes impact on their daily living activities. Synonymous of VI are blindness, low vision, subnormal vision, visual incapacity, although there are peculiarities among them. The autonomic nervous system (ANS) provides the body with dynamic adaptation, moment by moment, according to changes in the internal and/or external body environment. As VI is an adverse condition, it is expected to be associated with changes in systemic autonomic activity, such as heart rate (HR) variability. OBJECTIVE: To analyze the blindness stress by monitoring the activity of the ANS in the heart in subjects submitted acutely to low vision and also in subjects with chronic visual deficiency. METHOD: This is a randomized trial experimental study. In this clinical trial, initially, patients will undergo an ophthalmologic medical evaluation, along with monitoring of HR and systolic blood pressure /diastolic blood pressure. Volunteers with normal vision (Group i); and people with VI (Group ii) will be evaluated, all of them inhabitants of Rio Branco City, capital of Acre State, Brazilian Amazon. The intervention will consist of simulating blindness by sealing both eyes of each participant with good eyesight, using a sleep mask and allowing maximum occlusion for 45 minutes, split into 3 periods of 15 minutes each. Still blindfolded, participants will be requested to perform different tasks as walking, serve themselves water and/or cookies, and engaging in playful-pedagogical activity. Identical procedure will be done with the group with VI. The HR will be recorded by the Polar RS800 HR monitor. All findings with a value of P < .05 will be considered statistically significant. As a risk measure the odds ratio will be calculated, adjusted, and not adjusted with their respective 95% confidence intervals. The odds ratio = 1 of lowest risk for the outcome of interest will be considered as the base category for each independent variable. ETHICS AND DISSEMINATION: This study will be carried out in accordance with the guidelines that regulate human research in Resolution No. 466/12 of the National Health Council. We obtained the approval of the Research Ethics Committee of the ABC Medical School/Faculdade de Medicina do ABC, with CAAE: 73945017.0.0000.0082, and Opinion No. 2,275,101. All individuals who agreed to participate in the study will sign the free and informed consent form (FICF). The FICF is also available in audio and Braille versions. The results will be disseminated through peer-reviewed journal articles and conferences. This study is registered in the Brazilian Registry of Clinical Trials under the number RBR-9sm9dp.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Frequência Cardíaca/fisiologia , Transtornos da Visão/fisiopatologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto , Adulto Jovem
3.
Medicine (Baltimore) ; 98(44): e17764, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31689836

RESUMO

While stress is known to cause many diseases, there is no established method to determine individuals vulnerable to stress. Sasang typology categorizes humans into four Sasang types (So-Eum, Tae-Eum, So-Yang, and Tae-Yang), which have unique pathophysiologies because of their differential susceptibilities to specific stimuli, including stress. The purpose of this study was to determine if Sasang typology can be used identify individuals who are vulnerable to stress by evaluation of heart rate variability (HRV).This was a cross-sectional study. A total of 399 healthy men and women aged 30 to 49 years were recruited. Physical examinations for stress included HRV measurement and blood tests. The subjects also completed questionnaires about psychological stress, self-awareness, and lifestyle. HRV was analyzed using frequency-domain analysis. Subjects were divided into So-Eum (SE) and non-So-Eum (non-SE) groups according to their diagnosis.The weight and body mass index in the SE group were significantly lower than those in the non-SE group (both, P = .000). There were no significant between-group differences in any other demographic variables. In HRV analysis, the normalized high frequency (nHF) was higher (P = .008) while the normalized low frequency (nLF; P = .008) and LF:HF ratio (LF/HF; P = .002) were lower in the SE group than in the non-SE group.Although there was no difference in variables affecting HRV, HRV values were significantly different between groups. The LF/HF value for the SE group was at the lower limit of the normal range, although there were no associated clinical problems. These findings suggest that individuals with the SE type are more susceptible to stress than those with the other types. Thus, middle-aged individuals who are vulnerable to stress can be identified using Sasang typology.


Assuntos
Suscetibilidade a Doenças/diagnóstico , Frequência Cardíaca/fisiologia , Medicina Tradicional Coreana/métodos , Psicometria/métodos , Estresse Psicológico/diagnóstico , Adulto , Índice de Massa Corporal , Estudos Transversais , Suscetibilidade a Doenças/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Somatotipos/psicologia , Estresse Psicológico/psicologia , Inquéritos e Questionários
4.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 31(9): 1128-1132, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31657338

RESUMO

OBJECTIVE: To investigate the effect of circadian heart rate variation on short-term and long-term mortality in intensive care unit (ICU) patients. METHODS: A retrospective cohort study was conducted. A total of 32 536 ICU patients were recorded from 2001 to 2008 published by Multiparameter Intelligent Monitoring in Intensive Care II (MIMIC-II v2.6) in April 2011. The circadian heart rate variation was defined as the ratio of mean nighttime (23:00 to 07:00) heart rate to mean daytime (07:00 to 23:00) heart rate. The 28-day mortality and 1-year mortality were defined as outcome events. The information such as age, gender, ethnicity, first sequential organ failure assessment (SOFA) score, first simplified acute physiology score I (SAPS I), usage of sedatives and catecholamines within 24 hours admission of ICU, clinical complications [hypertension, chronic obstructive pulmonary disease (COPD), diabetes with or without complications, congestive heart failure, liver disease, renal failure, etc.], and the complete heart rate records within 24 hours after ICU admission were collected. Cox proportional risk regression models were used to investigate the association between circadian heart rate variation and 28-day mortality and 1-year mortality in ICU patients. Besides, subgroup analysis was also performed in patients with different first SOFA scores. RESULTS: Totally 15 382 ICU patients in MIMIC-II database were enrolled, excluding the patients without heart rate records or death records, using pacemaker with arrhythmia, without SOFA or SAPS I score records. Finally, 9 439 patients were enrolled in the study cohort. (1) Cox regression analysis of the whole patient showed that the higher circadian heart rate variation was correlated with the increased 28-day mortality [hazard ratio (HR) = 1.613, 95% confidence interval (95%CI) was 1.338-1.943, P < 0.001] and 1-year mortality (HR = 1.573, 95%CI was 1.296-1.908, P < 0.001). After adjustment for demographic factors (age, gender and ethnicity), severity of illness (SOFA and SAPS I scores), clinical complications (hypertension, COPD, diabetes with or without complications, congestive heart failure, liver disease, renal failure, etc.), and influence of medications (sedatives and catecholamines), the night-day heart rate ratio was also correlated with 28-day mortality (HR = 1.256, 95%CI was 1.018-1.549, P = 0.033) and 1-year mortality (HR = 1.249, 95%CI was 1.010-1.545, P = 0.040). (2) According to the SOFA score (median value of 5), the patients were divided into two subgroups, in which 5 478 patients with SOFA score ≤ 5 and 3 961 patients with SOFA score > 5. Cox regression subgroup analysis showed that circadian heart rate variation was related with higher 28-day mortality (HR = 1.430, 95%CI was 1.164-1.756, P = 0.001) and 1-year mortality (HR = 1.393, 95%CI was 1.123-1.729, P = 0.003) in patients with SOFA score > 5. After adjustment for covariates, the 28-day mortality (HR = 1.279, 95%CI was 1.032-1.584, P = 0.025) and 1-year mortality (HR = 1.255, 95%CI was 1.010-1.558, P = 0.040) also increased with the increasing of night-day heart rate ratio in patients with SOFA score > 5. However, the relationships did not exist in patients with SOFA score ≤ 5. CONCLUSIONS: In ICU patients, the 28-day mortality and 1-year mortality increase with the higher circadian heart rate variation, which indicates that the circadian heart rate variation in ICU patients is positively correlated with the short-term and long-term mortality, especially in patients with relatively severe illness.


Assuntos
Relógios Circadianos , Frequência Cardíaca/fisiologia , Unidades de Terapia Intensiva , Mortalidade/tendências , Cuidados Críticos , Humanos , Escores de Disfunção Orgânica , Prognóstico , Estudos Retrospectivos
5.
J Strength Cond Res ; 33(11): 3151-3161, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31658212

RESUMO

Bycura, DK, Dmitrieva, NO, Santos, AC, Waugh, KL, and Ritchey, KM. Efficacy of a Goal Setting and Implementation Planning Intervention on Firefighters' Cardiorespiratory Fitness. J Strength Cond Res 33(11): 3151-3161, 2019-The purpose of this study was to assess the effectiveness of a goal setting and implementation planning (GSIP) intervention on cardiorespiratory fitness among firefighters. Male career firefighters (N = 20) from a large municipal fire department were assigned to an intervention arm (n = 12) or passive control arm (n = 8) of a 14-week study involving cardiorespiratory exercise. The intervention consisted of GSIP coaching at baseline and support throughout the study. Cardiorespiratory fitness was assessed through a standardized physical protocol for firefighters (Candidate Physical Ability Test) at baseline, at 6 weeks, and at 14 weeks time points, using the Cosmed K4b portable metabolic system to measure physiological variables. Using intention-to-treat principles, we employed a 2-level multilevel model to examine the effect of intervention group on intercept and change over time on primary outcomes of interest: oxygen transport and utilization (VO2), heart rate (HR), and respiratory exchange ratio (R). Results demonstrated that the intervention and control groups both exhibited a significant increase in VO2 (B = 0.143, SE = 0.025, p < 0.001) and a decline in R (B = -0.003. SE = 0.001, p < 0.01) over the course of the study. Although both groups exhibited improvements on 2 of the 3 cardiorespiratory outcomes, subjects assigned to the intervention did not exhibit superior outcomes when compared to the control group. Given the improvements we observed in 2 out of 3 outcomes across both conditions, future research may consider testing effectiveness of interventions consisting of functional training exercises that closely translate to firefighting tasks over time periods sufficient to elicit aerobic metabolic adaptations.


Assuntos
Aptidão Cardiorrespiratória , Bombeiros , Metas , Adaptação Fisiológica , Adulto , Exercício , Teste de Esforço , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio
6.
Medicine (Baltimore) ; 98(41): e17400, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31593091

RESUMO

INTRODUCTION: Cardiac autonomic modulation is an important marker of cardiovascular health and the practice of physical activity is a fundamental tool for good maintenance or increments in this marker. However, it is not clear in the literature whether different intensities and different domains of physical activity are related in the same way to cardiac autonomic modulation. OBJECTIVES: This randomized epidemiologic study will examine the relationship between cardiac autonomic modulation and different intensities and domains of physical activity in a representative sample of adults. METHODS: The sample of study will consist of 252 subjects aged from 18 years and above. The sample will be randomized through census sectors in which the neighborhoods, streets, and houses will also be randomized. Cardiac autonomic modulation will be assessed by heart rate variability and the intensity (mild, moderate, intense) of physical activity will be evaluated by means of accelerometers, while the different domains of physical activity (physical activity at work, occupational activities) will be evaluated through a questionnaire. The relationship between cardiac autonomic modulation and different physical activity intensities, as well as the different domains will be analyzed by linear regression, considering a statistical significance of 5% and a 95% confidence interval. This research protocol is registered in ClinicalTrials.gov at number NCT03986879.


Assuntos
Acelerometria/estatística & dados numéricos , Sistema Nervoso Autônomo/fisiologia , Exercício/fisiologia , Coração/fisiologia , Esforço Físico/fisiologia , Adolescente , Adulto , Feminino , Frequência Cardíaca/fisiologia , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Estudos Observacionais como Assunto , Inquéritos e Questionários , Adulto Jovem
7.
Niger J Clin Pract ; 22(10): 1349-1355, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31607723

RESUMO

Objective: The objective of the this study is to document the existence of statistically significant differences between parameters of heart rate variability (HRV) and heart rate turbulence (HRT), determined in women with overt hyperthyroidism (hT), compared to controls and to highlight their correlations with the level of thyroid hormones and the incidence of arrhythmias. Methods: We studied the HRV in time and frequency domain, and the HRT in a group of 113 women with overt hT, without other cardiovascular risk factors or comorbidities, admitted to the endocrinology clinic of our hospital, between 2012 and 2016. Depending on the severity and duration of hT and levels of thyroid hormones, the patients were assigned to three groups: mild and moderate forms, severe hT with thyrotoxicosis and persistent cases with a relapse of hT. We performed 24 h Holter monitoring in all patients. Results: HRV parameters in time domain (TD) were significantly depressed in patients comparing to controls. All patients had abnormal, positive values of turbulence onset (TO) with significant statistically differences (P < 0.0001) comparing to controls. Although positive, the values of turbulence slope (TS) decreased according to the severity of hT. Conclusion: Patients with hT had depressed values of HRV parameters in TD, correlated with the severity of the thyroid disease and with the incidence of arrhythmias. All patients presented pathological values of TO. TS values were positive, but lower compared to controls.


Assuntos
Arritmias Cardíacas/diagnóstico , Eletrocardiografia Ambulatorial/métodos , Frequência Cardíaca/fisiologia , Hipertireoidismo/complicações , Hormônios Tireóideos/sangue , Adulto , Arritmias Cardíacas/epidemiologia , Estudos de Casos e Controles , Doença Crônica , Comorbidade , Feminino , Humanos , Hipertireoidismo/epidemiologia , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença
9.
Medicine (Baltimore) ; 98(43): e17600, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31651868

RESUMO

BACKGROUND: Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a complex condition with no reliable diagnostic biomarkers. Studies have shown evidence of autonomic dysfunction in patients with ME/CFS, but results have been equivocal. Heart rate (HR) parameters can reflect changes in autonomic function in healthy individuals; however, this has not been thoroughly evaluated in ME/CFS. METHODS: A systematic database search for case-control literature was performed. Meta-analysis was performed to determine differences in HR parameters between ME/CFS patients and controls. RESULTS: Sixty-four articles were included in the systematic review. HR parameters assessed in ME/CFS patients and controls were grouped into ten categories: resting HR (RHR), maximal HR (HRmax), HR during submaximal exercise, HR response to head-up tilt testing (HRtilt), resting HR variability (HRVrest), HR variability during head-up tilt testing (HRVtilt), orthostatic HR response (HROR), HR during mental task(s) (HRmentaltask), daily average HR (HRdailyaverage), and HR recovery (HRR) Meta-analysis revealed RHR (MD ±â€Š95% CI = 4.14 ±â€Š1.38, P < .001), HRtilt (SMD ±â€Š95% CI = 0.92 ±â€Š0.24, P < .001), HROR (0.50 ±â€Š0.27, P < .001), and the ratio of low frequency power to high frequency power of HRVrest (0.39 ±â€Š0.22, P < .001) were higher in ME/CFS patients compared to controls, while HRmax (MD ±â€Š95% CI = -13.81 ±â€Š4.15, P < .001), HR at anaerobic threshold (SMD ±â€Š95% CI = -0.44 ±â€Š0.30, P = 0.005) and the high frequency portion of HRVrest (-0.34 ±â€Š0.22, P = .002) were lower in ME/CFS patients. CONCLUSIONS: The differences in HR parameters identified by the meta-analysis indicate that ME/CFS patients have altered autonomic cardiac regulation when compared to healthy controls. These alterations in HR parameters may be symptomatic of the condition.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Encefalomielite/fisiopatologia , Síndrome de Fadiga Crônica/fisiopatologia , Coração/fisiopatologia , Adulto , Idoso , Exercício/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Síndrome , Teste da Mesa Inclinada
10.
Braz J Med Biol Res ; 52(9): e8402, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31482976

RESUMO

Cardiopulmonary fitness assessment is a valuable resource to obtain quantitative indicators of an individual's physical performance. The cardiopulmonary exercise test (CPX), considered the gold standard test for this evaluation, is costly and difficult to be accessed by the general population. In order to make this evaluation more accessible, and to better reflect the performance of daily life activities, alternative tests were proposed. Morbidly obese patients present limitations that impair physical performance assessment and could benefit from a test of shorter duration, provided it is validated. This observational study aimed to validate the two-minute step test (2MST) as a tool to evaluate functional capacity (FC) in obese with comorbidities and morbidly obese patients, compared the 2MST with CPX as a measure of physical performance, and developed a predictive equation to estimate peak oxygen uptake (VO2) in the 2MST. The CPX and the 2MST were performed and metabolic and ventilatory parameters were recorded in 31 obese individuals (BMI>35 kg/m2). Pearson correlation and multiple linear regression analyses were performed to evaluate the peak VO2 best predictors. Bland-Altman analysis was performed to assess the agreement between the two methods. Peak VO2 measured by CPX and 2MST showed a strong correlation (r=0.70, P<0.001) and there was a moderate correlation between peak VO2 of the 2MST and the number of up-and-down step cycles (UDS) (r=0.55; P=0.01). The reference equation obtained was: VO2 (mL·kg-1·min-1) = 13.341 + 0.138 × total UDS - (0.183 × BMI), with an estimated standard error of 1.3 mL·kg-1·min-1. The 2MST is a viable, practical, and easily accessible test for FC. UDS and BMI can predict peak VO2 satisfactorily.


Assuntos
Aptidão Cardiorrespiratória/fisiologia , Tolerância ao Exercício/fisiologia , Frequência Cardíaca/fisiologia , Obesidade/fisiopatologia , Consumo de Oxigênio/fisiologia , Teste de Caminhada/métodos , Adolescente , Adulto , Comorbidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade Mórbida/fisiopatologia , Fatores de Tempo , Adulto Jovem
11.
Environ Pollut ; 254(Pt B): 113054, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31473392

RESUMO

Indoor air pollution is associated with numerous adverse health outcomes. Air purifiers are widely used to reduce indoor air pollutants. Ionization air purifiers are becoming increasingly popular for their low power consumption and noise, yet its health effects remain unclear. This randomized, double-blind crossover study is conducted to explore the cardiorespiratory effects of ionization air purification among 44 children in Beijing. Real or sham purification was performed in classrooms for 5 weekdays. Size-fractionated particulate matter (PM), black carbon (BC), ozone (O3), and negative air ions (NAI) were monitored, and cardiorespiratory functions were measured. Mixed-effect models were used to establish associations between exposures and health parameters. Real purification significantly decreased PM and BC, e.g. PM0.5, PM2.5, PM10 and BC were decreased by 48%, 44%, 34% and 50%, respectively. O3 levels were unchanged, while NAI was increased from 12 cm-3 to 12,997 cm-3. Real purification was associated with a 4.4% increase in forced exhaled volume in 1 s (FEV1) and a 14.7% decrease in fractional exhaled nitrogen oxide (FeNO). However, heart rate variability (HRV) was altered negatively. Interaction effects of NAI and PM were observed only on HRV, and alterations in HRV were greater with high NAI. Ionization air purifier could bring substantial respiratory benefits, however, the potential negative effects on HRV need further investigation.


Assuntos
Filtros de Ar , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/prevenção & controle , Adolescente , Ionização do Ar , Poluição do Ar/efeitos adversos , Poluição do Ar em Ambientes Fechados/análise , Pequim , Criança , Estudos Cross-Over , Método Duplo-Cego , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Óxidos de Nitrogênio , Material Particulado/análise , Testes de Função Respiratória , Fuligem
12.
Br J Anaesth ; 123(6): 758-767, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31492527

RESUMO

BACKGROUND: Myocardial injury is more frequent after noncardiac surgery in patients with preoperative cardiac vagal dysfunction, as quantified by delayed heart rate (HR) recovery after cessation of cardiopulmonary exercise testing. We hypothesised that serial and dynamic measures of cardiac vagal activity are also associated with myocardial injury after noncardiac surgery. METHODS: Serial autonomic measurements were made before and after surgery in patients undergoing elective noncardiac surgery. Cardiac vagal activity was quantified by HR variability and HR recovery after orthostatic challenge (supine to sitting). Revised cardiac risk index (RCRI) was calculated for each patient. The primary outcome was myocardial injury (high-sensitivity troponin ≥15 ng L-1) within 48 h of surgery, masked to investigators. The exposure of interest was cardiac vagal activity (high-frequency power spectral analysis [HFLn]) and HR recovery 90 s from peak HR after the orthostatic challenge. RESULTS: Myocardial injury occurred in 48/189 (25%) patients, in whom 41/48 (85%) RCRI was <2. In patients with myocardial injury, vagal activity (HFLn) declined from 5.15 (95% confidence interval [CI]: 4.58-5.72) before surgery to 4.33 (95% CI: 3.76-4.90; P<0.001) 24 h after surgery. In patients who remained free of myocardial injury, HFLn did not change (4.95 [95% CI: 4.64-5.26] before surgery vs 4.76 [95% CI: 4.44-5.08] after surgery). Before and after surgery, the orthostatic HR recovery was slower in patients with myocardial injury (5 beats min-1 [95% CI: 3-7]), compared with HR recovery in patients who remained free of myocardial injury (10 beats min-1 [95% CI: 7-12]; P=0.02). CONCLUSIONS: Serial HR measures indicating loss of cardiac vagal activity are associated with perioperative myocardial injury in lower-risk patients undergoing noncardiac surgery.


Assuntos
Infarto do Miocárdio/fisiopatologia , Isquemia Miocárdica/fisiopatologia , Complicações Pós-Operatórias/fisiopatologia , Procedimentos Cirúrgicos Operatórios , Nervo Vago/fisiopatologia , Idoso , Estudos de Coortes , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
13.
Int J Sports Med ; 40(12): 756-761, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31476782

RESUMO

We studied the effects of supramaximal interval exercise (SIE) with or without antihypertensive medication (AHM) on 21-hr blood pressure (BP) response. Twelve hypertensive patients chronically medicated with AHM, underwent three trials in a randomized order: a) control trial without exercise and substituting their AHM with a placebo (PLAC); b) placebo medicine and a morning bout of SIE (PLAC+SIE), and c) combining AHM and exercise (AHM+SIE). Acute and ambulatory blood pressure responses were measured for 21-hr after treatment. 20 min after treatment, systolic blood pressure (SBP) readings were reduced, similar to readings after PLAC+SIE (-9.7±6.0 mmHg, P<0.001) and AHM+SIE (-10.4±7.9 mmHg, P=0.001). 21 h after treatment, SBP remained reduced after PLAC+SIE (125±12 mmHg, P=0.022) and AHM+SIE (122±12 mmHg, P=0.013) compared to PLAC (132±16 mmHg). The BP reduction in PLAC+SIE faded out at 4 a.m., while in AHM+SIE it continued overnight. At night, BP reduction was larger in AHM+SIE than PLAC+SIE (-5.6±4.0 mmHg, P=0.006). Our data shows that a bout of supramaximal aerobic interval exercise in combination with ARB medication in the morning elicits a sustained blood pressure reduction lasting at least 21-h. Thus, the combination of exercise and angiotensin receptor blocker medication seems superior to exercise alone for acutely decreasing blood pressure.


Assuntos
Anti-Hipertensivos/uso terapêutico , Treinamento Intervalado de Alta Intensidade , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Hipotensão Pós-Exercício/fisiopatologia , Actigrafia/métodos , Idoso , Pressão Sanguínea/fisiologia , Estudos Cross-Over , Método Duplo-Cego , Feminino , Monitores de Aptidão Física , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Postura/fisiologia , Estudos de Tempo e Movimento
14.
Br J Radiol ; 92(1103): 20190384, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31479307

RESUMO

OBJECTIVE: Evaluation of coronary CT image blur using multi segment reconstruction algorithm. METHODS: Cardiac motion was simulated in a Catphan. CT coronary angiography was performed using 320 × 0.5 mm detector array and 275 ms gantry rotation. 1, 2 and 3 segment reconstruction algorithm, three heart rates (60, 80 and 100bpm), two peak displacements (4, 8 mm) and three cardiac phases (55, 35, 75%) were used. Wilcoxon test compared image blur from the different reconstruction algorithms. RESULTS: Image blur for 1, 2 and 3 segments in: 60 bpm, 75% R-R interval and 8 mm peak displacement: 0.714, 0.588, 0.571 mm (1.18, 0.6, 0.4 mm displacement) 80 bpm, 35% R-R interval and 8 mm peak displacement: 0.869, 0.606, 0.606 mm (1.57, 0.79,0.52 mm displacement) 100 bpm, 35% R-R interval and 4 mm peak displacement: 0.645, 0.588, 0.571 mm (0.98, 0.49, 0.33 mm displacement). The median image blur overall for 1 and 2 segments was 0.714 mm and 0.588 mm respectively (p < 0.0001). CONCLUSION: Two-segment reconstruction significantly reduces image blur. ADVANCES IN KNOWLEDGE: Multisegment reconstruction algorithms during CT coronary angiography are a useful method to reduce image blur, improve visualization of the coronary artery wall and help the early detection of the plaque.


Assuntos
Angiografia por Tomografia Computadorizada/normas , Doença da Artéria Coronariana/diagnóstico por imagem , Algoritmos , Análise de Variância , Artefatos , Doença da Artéria Coronariana/fisiopatologia , Frequência Cardíaca/fisiologia , Humanos , Movimento , Imagens de Fantasmas , Projetos Piloto , Estudos Prospectivos , Intensificação de Imagem Radiográfica/métodos
15.
Postgrad Med ; 131(7): 539-545, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31482757

RESUMO

Objectives: Cardiac autonomic nervous system (ANS) dysfunction is a common feature in patients receiving hemodialysis (HD) therapy, whilst is associated with an increased risk of ventricular arrhythmias and sudden cardiac death. The aim of this study is to investigate and compare the hemodynamic changes and responses of ANS function in HD patients using pupillometry and Heart Rate Variability (HRV) parameters. Methods: Sixteen chronic kidney diseases (CKD) patients receiving HD (52.18 ± 17.7 years) underwent both pupillometric measurements using a portable handheld pupil-measuring device and standard HRV analysis pre HD, every hour and 30 min post-HD session under two different scenarios: at rest while the patient resting at HD bed and when the patient performed a single bout of intradialytic aerobic exercise lasting for 45 min during the second hour of the HD therapy. Results: No significant changes in ANS values were observed in neither of the pupillometric and the HRV values pre HD, for each hour and post-HD session. HRV parameters were significantly correlated with pupillometric parameters at pre HD and immediately after the single bout of intradialytic exercise. ANS activity did not differ during the conventional HD session and during the session included intradialytic exercise. Moreover, sympatho-vagal balance indices deriving from pupillometric assessment showed beneficial changes after the exercise event. Conclusion: Pupillometry is a promising and robust technique with fewer artifacts compared to HRV especially in studies involving exercise sessions. Thus, pupillometry can be used as a complementary tool in the evaluation of cardiac autonomic dysfunction.


Assuntos
Doenças do Sistema Nervoso Autônomo/fisiopatologia , Exercício/fisiologia , Frequência Cardíaca/fisiologia , Pupila/fisiologia , Diálise Renal , Insuficiência Renal Crônica/terapia , Adulto , Idoso , Sistema Nervoso Autônomo/fisiopatologia , Humanos , Pessoa de Meia-Idade , Insuficiência Renal Crônica/fisiopatologia
16.
Medicine (Baltimore) ; 98(34): e16938, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31441885

RESUMO

We aimed to investigate heart rate recovery (HRR) in patients with transient ischemic attack (TIA) and the relationship between HRR and health-related quality of life (HRQOL).All available patients were enrolled during the enrollment period. A total of 120 patients with TIA and 120 healthy controls were included in this study. A treadmill stress test was performed to calculate the HRR. The HRR were calculated as follows: HRR 1, 2, 3, and 5 minutes = heart rate at peak during exercise - heart rate at 1, 2, 3, and 5 minutes at rest. All patients enrolled were asked to fill in the Short Form 36 Health Survey to calculate HRQOL.We found that the maximum heart rate of TIA patients was significantly higher than that of healthy controls (166 ±â€Š11 vs. 162 ±â€Š14 beats/min, P = .015). Similarly, maximum systolic blood pressure (SBP) and diastolic blood pressure (DBP) were higher in TIA group compared with healthy control group (SBP: 172 ±â€Š15 vs. 165 ±â€Š14 mm Hg, P < .001; DBP: 102 ±â€Š12 vs. 93 ±â€Š16 mm Hg, P < .001). The HRR were significantly lower in TIA group compared with control group (TIA vs. controls, HRR1: 17 ±â€Š7 vs. 30 ±â€Š8 beats/min, HRR2: 32 ±â€Š11 vs. 49 ±â€Š9 beats/min, HRR3: 43 ±â€Š13 vs. 63 ±â€Š12 beats/min, HRR5: 54 ±â€Š16 vs. 73 ±â€Š15 beats/min, all P < .001). Multivariate analysis showed that older age (P = .03) and high BMI (P = .04) were risk factors associated with abnormal HRR in patients with TIA. With regard to HRQOL, we found that role limitations due to physical problems, general health, vitality, and role limitations due to emotional problems were significantly lower in patients with abnormal HRR compared with patients with normal HRR. Multivariate analysis showed that older age (P = .04) and abnormal HRR (P = .03) were predictors for poor HRQOL in TIA patients.HRR was impaired in patients with TIA. In addition, TIA patients with abnormal HRR suffered from a significantly poorer HRQOL. Hence, given the prognostic value of HRR, patients with TIA should be monitored to prevent cardiovascular events and to improve HRQOL.


Assuntos
Frequência Cardíaca/fisiologia , Ataque Isquêmico Transitório/fisiopatologia , Qualidade de Vida , Adulto , Fatores Etários , Pressão Sanguínea , Índice de Massa Corporal , Estudos de Casos e Controles , Eletrocardiografia , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recuperação de Função Fisiológica/fisiologia , Inquéritos e Questionários
17.
J Sports Med Phys Fitness ; 59(8): 1281-1284, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31373188

RESUMO

BACKGROUND: The use of smartphone applications to monitor heart rate has become increasingly popular. However, there is limited research available on the validity of these applications. The purpose of this study was to examine the accuracy of a free heart rate monitoring application on two smartphone platforms while at rest and during moderate intensity exercise. One heart rate monitor application was chosen for two different technological platforms. METHODS: Twenty-four adults aged 18 and older (six males, 18 females) were randomly assigned a platform. Two groups were formed based on the platform being utilized. Both groups were monitored using an electrocardiograph (ECG) and the smart phone application. Heart rate for each participant was recorded while seated before exercise, and during moderate intensity exercise on an elliptical machine. Measurements were recorded in one-minute intervals. RESULTS: Data was analyzed using correlations and t-tests between platforms. All data was analyzed for both resting and exercise heart rate averages. There was no significant difference in heart rate while seated, t-test (-1.33; P=0.197) nor exercise heart rate, t-test (-1.54; P=0.142) when comparing means of the two platforms to an ECG. CONCLUSIONS: The applications chosen for both platforms to monitor heart rate were found to be fairly accurate, especially at rest. There are small user adaptations for monitoring heart rate, but heart rate applications provide a low-cost and efficient method for non-medical heart rate tracking. Future research should investigate the difference in accuracy for skin tone, ethnicity, race, hand size, and callosity of fingertips.


Assuntos
Frequência Cardíaca/fisiologia , Aplicativos Móveis/normas , Monitorização Fisiológica/instrumentação , Smartphone , Adulto , Eletrocardiografia , Exercício/fisiologia , Feminino , Humanos , Masculino , Adulto Jovem
18.
Braz J Med Biol Res ; 52(8): e8088, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31389489

RESUMO

There is currently a lack of information adjacent on the influence of sex and age in heart rate variability (HRV), adjusted according to accelerometer-based physical activity (PADL). We hypothesized that the effect of sex and age on the HRV should be reduced or absent in individuals with a suitable PADL level. We aim to evaluate the influence of sex and age on HRV, adjusted for the confounding effects of the PADL level. A total of 485 age-stratified subjects (18-39, 40-59, and ≥60 years) underwent HRV analyses at rest and 7-day assessments of accelerometer-based PADL. Multivariate analyses of covariance were done using log-transformed HRV indices as outcomes, age and sex as fixed factors, and PADL, cardiovascular risk, fat body mass, and heart rate (HR) at rest as covariates. Despite the adjustment for directly measured PADL, women had better indices of vagal tone, whereas men had higher sympathetic influence. Also, compared to middle-aged and older adults, younger individuals (ages 18-39 years) presented better HRV. Multiple regression analyses confirmed that age and sex were the main predictors of HRV indices, even after adjusting for PADL directly assessed by triaxial accelerometer and HR. We also observed that the correlation between some HRV indexes and the different indexes of physical activity directly evaluated was significant, but not very consistent. Thus, HRV indices are influenced by age and sex, regardless of accelerometer-based physical activity. Interventions with physical activity and exercise aimed at improving the autonomic modulation of asymptomatic adults should take such differences into account.


Assuntos
Fatores Etários , Doenças Cardiovasculares/fisiopatologia , Exercício/fisiologia , Frequência Cardíaca/fisiologia , Fatores Sexuais , Acelerometria , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
19.
Hypertension ; 74(4): 903-909, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31378103

RESUMO

True drug-resistant hypertension (RHT) is characterized by a marked neuroadrenergic activation and reflex alterations compared with the nonresistant hypertensive state. It is unknown however, whether this behavior is specific for the RHT state or is also shared by apparent RHT (ARHT). In 38 middle-age patients with RHT, 44 treated essential controlled hypertensives (HT) and 32 ARHT; we evaluated sphygmomanometric, beat-to-beat (Finapres) and 24-hour (Spacelabs) blood pressure, heart rate and muscle sympathetic nerve traffic (microneurography). Measurements included plasma aldosterone, plasma norepinephrine, homeostasis model assessment index, and spontaneous baroreflex-muscle sympathetic nerve traffic sensitivity. All the various above-mentioned blood pressure values were significantly greater in both RHT and ARHT as compared with HT, while 24-hour blood pressure was significantly lower in ARHT as compared with RHT. In ARHT, muscle sympathetic nerve traffic was significantly lower than RHT (74.8±5.2 versus 89.2±4.8 bursts/100 hb, P<0.01) and similar to HT (69.7±4.8 bursts/100 hb, P=NS). RHT showed, at variance from the other 2 groups, greater plasma aldosterone and homeostasis model assessment index values and an impaired baroreflex function. In RHT, but not in ARHT and HT, muscle sympathetic nerve traffic was significantly and inversely related to baroreflex function (r=-0.40, P<0.02) and directly to plasma aldosterone and homeostasis model assessment index values (r=0.34-0.36, P<0.05). Plasma norepinephrine and heart rate values were not significantly different in the 3 groups. These data provide evidence that the marked sympathetic activation and baroreflex dysfunction detected in RHT is not present in ARHT, which displays a sympathetic and baroreflex profile superimposable to that seen in HT. These differences in the neurogenic function may have important clinical and therapeutic implications.


Assuntos
Barorreflexo/fisiologia , Pressão Sanguínea/fisiologia , Hipertensão/fisiopatologia , Sistema Nervoso Simpático/fisiopatologia , Adulto , Idoso , Aldosterona/sangue , Feminino , Frequência Cardíaca/fisiologia , Humanos , Hipertensão/sangue , Resistência à Insulina/fisiologia , Masculino , Pessoa de Meia-Idade , Norepinefrina/sangue
20.
Hypertension ; 74(4): 888-895, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31401880

RESUMO

To study the contribution of sympathetic nerve activity (SNA) to the development of hypertension, experiments were designed to continuously and simultaneously measure renal (RSNA) and lumbar SNA (LSNA) during the development of hypertension induced by 8% salt loading in Dahl salt-sensitive (DS) rats. Male DS and salt-resistant rats were instrumented with bipolar electrodes to record RSNA and LSNA and a telemeter to record arterial pressure (AP). AP increased during the first 3 days after the onset of salt loading by ≈10 mm Hg in both DS and Dahl salt-resistant rats. AP continued to increase progressively from day 4 to day 14 of salt loading by 33±1 mm Hg in DS rats, while it remained the same in Dahl salt-resistant rats. RSNA and LSNA increased in the initial few days by 6% to 8%, and decreased gradually thereafter, suggesting that increases in neither RSNA nor LSNA are directly linked with the progressive increase in AP induced by salt loading in DS rats. After the cessation of salt loading, AP pressure returned to the presalt loading level in both DS and Dahl salt-resistant rats. RSNA increased significantly by 32±3% after the cessation of salt loading, while LSNA remained the same in DS rats, suggesting that salt-sensitive mechanisms respond to a loss of sodium, not a gain, and selectively activate RSNA in DS rats. In summary, RSNA and LSNA are not likely to be a primary trigger to initiate the progressive increase in AP induced by 8% salt loading in DS rats.


Assuntos
Pressão Sanguínea/fisiologia , Hipertensão/fisiopatologia , Rim/inervação , Cloreto de Sódio na Dieta , Sistema Nervoso Simpático/fisiopatologia , Animais , Frequência Cardíaca/fisiologia , Masculino , Ratos , Ratos Endogâmicos Dahl
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