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Introduction: Due to functional and autonomic difficulties faced by individuals with Duchenne Muscular Dystrophy (DMD), the use of assistive technology is critical to provide or facilitate functional abilities. The key objective was to investigate acute cardiac autonomic responses, by application of Heart Rate Variability (HRV), during computer tasks in subjects with DMD via techniques based on non-linear dynamics. Method: HRV was attained via a Polar RS800CX. Then, was evaluated by Chaotic Global Techniques (CGT). Forty-five male subjects were included in the DMD group and age-matched with 45 in the healthy Typical Development (TD) control group. They were assessed for 20 min at rest sitting, and then 5 min whilst performing the maze task on a computer. Results: Both TD and DMD subjects exhibited a significantly reduced HRV measured by chaotic global combinations when undertaking the computer maze paradigm tests. DMD subjects presented decreased HRV during rest and computer task than TD subjects. Conclusion: While there is an impaired HRV in subjects with DMD, there remains an adaptation of the ANS during the computer tasks. The identification of autonomic impairment is critical, considering that the computer tasks in the DMD community may elevate their level of social inclusion, participation and independence.

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OBJECTIVE: To analyze the effect of air pollution on heart rate variability in overweight individuals. METHODS: A total of 46 adult individuals, both sexes, aged between 18 and 49 years and with body mass index >25kg/m2 were analyzed. All volunteers were students from public schools of two cities in the state of São Paulo. The clinical, demographic and anthropometric data of each individual, as well as heart rate variability through time domain, geometric and frequency indices were collected. For the air quality analysis, the following variables were investigated: concentration of carbon dioxide, particulate matter, temperature and relative humidity. The analysis was carried out with descriptive and analytical statistics, adopting a level of significance of 5%. RESULTS: There was a reduction in overall heart rate variability in overweight individuals by the following indices: mean standard deviation of all normal RR intervals, long-term standard deviation of continuous RR intervals, ratio of short-and long-term standard deviation of continuous RR intervals. In addition, the indices responsible for parasympathetic control showed a downward trend in their values, as well as the low frequency index, which represented sympathetic action, although not significant. CONCLUSION: Overweight individuals exposed to air pollution had lower heart rate variability than the Control Group.

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ABSTRACT Objective: To analyze the effect of air pollution on heart rate variability in overweight individuals. Methods: A total of 46 adult individuals, both sexes, aged between 18 and 49 years and with body mass index >25kg/m2 were analyzed. All volunteers were students from public schools of two cities in the state of São Paulo. The clinical, demographic and anthropometric data of each individual, as well as heart rate variability through time domain, geometric and frequency indices were collected. For the air quality analysis, the following variables were investigated: concentration of carbon dioxide, particulate matter, temperature and relative humidity. The analysis was carried out with descriptive and analytical statistics, adopting a level of significance of 5%. Results: There was a reduction in overall heart rate variability in overweight individuals by the following indices: mean standard deviation of all normal RR intervals, long-term standard deviation of continuous RR intervals, ratio of short-and long-term standard deviation of continuous RR intervals. In addition, the indices responsible for parasympathetic control showed a downward trend in their values, as well as the low frequency index, which represented sympathetic action, although not significant. Conclusion: Overweight individuals exposed to air pollution had lower heart rate variability than the Control Group.

RESUMO Objetivo: Analisar o efeito da poluição atmosférica na variabilidade da frequência cardíaca em indivíduos com excesso de peso. Métodos: Foram analisados 46 indivíduos adultos, de ambos os sexos, com idade entre 18 e 49 anos e índice de massa corporal >25kg/m2. Todos os voluntários eram estudantes da Educação de Jovens e Adultos em duas cidades do estado de São Paulo. Foram coletadas informações clínicas, demográficas e antropométricas de cada indivíduo, bem como a variabilidade da frequência cardíaca, por meio dos índices do domínio do tempo, geométricos e de frequência. Para a análise da qualidade do ar, foram investigadas as variáveis concentração de dióxido de carbono, material particulado, temperatura e umidade do ar. A análise se deu por estatística descritiva e analítica, adotando-se nível de significância de 5%. Resultados: Ocorreu redução na variabilidade da frequência cardíaca geral nos indivíduos com excesso de peso por meio dos índices geométricos (desvio padrão a longo prazo dos intervalos RR contínuos, e a razão entre as variações curta e longa dos intervalos RR) e o domínio do tempo (desvio padrão da média de todos os intervalos RR normais). Índices responsáveis pelo controle parassimpático mostraram-se com tendência de queda em seus valores, bem como o índice de baixa frequência que representava a ação do simpático, embora com valores não significativos. Conclusão: Indivíduos com excesso de peso expostos à poluição atmosférica apresentaram menor variabilidade da frequência cardíaca em comparação ao Grupo Controle.

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This study addresses evidence concerning elastic tubing resistance training (ET) on autonomic modulation in patients with chronic obstructive pulmonary disease (COPD). Autonomic dysfunction is common in COPD and contributes to the development of arrhythmias and sudden death. Along with autonomic dysfunction, muscle dysfunction is related to functional limitations and prognosis of the disease. This study investigated the effects of ET on autonomic modulation, muscle strength, and walking distance in COPD. Subjects were divided into two groups, ET (n = 20; 66,5 ± 8,9 y; 25,5 ± 3,5 kg/m2; FEV1/FVC: 50,3 ± 11,0) and conventional training (n = 19; 66,0 ± 6,9; 27,1 ± 4,3; FEV1/FVC: 55,05 ± 9,56). Both groups undertook 24 sessions for 60 minutes, 3 times in a week. The significance level was p ≤ 0,05. Autonomic modulation was evaluated using heart rate variability in the time (rMSSD, ms) and frequency domain (HF, ms). Strength for upper and lower limbs was measured using dynamometry and walking distance was measured using a 6-minute walking test. There were no significant differences in the outcomes between groups. There was an increment to rMSSD [(16,7 ± 11,0 versus 20,8 ± 14,9) versus (14,2 ± 10,0 versus 17,4 ± 12,1)], HF [(141,9 ± 191,3 versus 234,9 ± 335,7) versus (94,1 ± 123,5 versus 177,6 ± 275,5)], shoulder abduction [(50,1 ± 19,6 versus 56,9 ± 20,4) versus (50,5 ± 19,0 versus 56,9 ± 19,3)], knee flexion [(101,9 ± 34,0 versus 116,8 ± 43,3) versus (98,6 ± 21,5 versus 115,1 ± 30,8)], and walking test [(433,0 ± 84,8 versus 468,9 ± 90,8) versus (397,4 ± 99,8 versus 426,3 ± 101,6)] after training for ET and conventional training, respectively. In conclusion, ET improves autonomic modulation in COPD with additional benefits for strength and cardiorespiratory capacity similar to conventional training.

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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.

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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.

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AIMS: Previous studies have reported right bundle branch block in Brugada syndrome. Subsequent analysis of electrocardiograms (ECGs) found one-third of cases classified as right bundle branch block did not meet criteria of a wide final S wave in the left leads. We aimed to study the role of the vectorcardiogram to characterize Brugada type 1 ECG pattern. METHODS AND RESULTS: Compare Frank-method vectorcardiogram in 11 patients with Brugada type 1 ECG pattern (BrS group) with vectorcardiogram of 20 healthy individuals with ECGs depicting incomplete right bundle branch block (IRBBB group) and 12 patients with complete right bundle branch block (CRBBB group). Initial 10-20 ms vector of the QRS loop in the horizontal plane (HP): BrS and IRBBB groups: Vector heading anterior and leftward. CRBBB group: Vector directed anterior and rightward. Right end conduction delay of the QRS loop: BrS group: Upper right quadrant of the frontal plane, right posterior quadrant of the HP. IRBBB group: Upper right quadrant of the frontal plane (30%) and right anterior quadrant of the HP (90%). CRBBB group: Upper right quadrant on the frontal plane (30%); all cases in the right anterior quadrant of the HP. 0 point (onset of QRS loop) and J point (end of QRS loop) relationship: BrS group: Not coincidental. IRBBB and CRBBB groups: Coincidental. T loop morphology, size, and appearance: BrS group: Circular, with symmetrical afferent and efferent limbs in 10 cases (90%). IRBBB and CRBBB groups: Elliptical or linear with slow inscription of efferent limb and rapid inscription of afferent limb. CONCLUSIONS: Vectorcardiograms in patients with Brugada type 1 ECG pattern have distinctive characteristics compared with healthy individuals with incomplete and CRBBB. These differences relate to the spatial location of the end conduction delay (right superior and posterior quadrant in the BrS group) and the morphology, size, and velocity of inscription of afferent and efferent limbs of the T loop (circular, small, of symmetrical limbs) and with a 1:1 length/width ratio.

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A hipertensão arterial sistêmica (HAS) é uma doença crônico-degenerativa, multifatorial, na maioria das vezes assintomática, de evolução lenta e progressiva que pode prejudicar a função de diversos órgãos nobres, como coração, cérebro, rins e olhos. O presente artigo enfoca a hipertensão arterial primária com aspectos epidemiológicos, diagnósticos, tratamento farmacológico e não farmacológico. A HAS constitui um grande problema social, visto que pode produzir lesões em órgãos-alvo em idade precoce e, portanto, produtiva do indivíduo, ocasionando altos custos socioeconômicos.Segundo o DATASUS, foi a quinta causa de morbidade em 2008 e a quinta causa de morbidade e mortalidade em 2006. O diagnóstico da HAS é feito com detalhada anamnese e exame físico, associados a duas ou mais mensurações pressóricas com valores maiores ou iguais a 140/90 mmHg, em dias e horários diferentes, observando-se a correta técnica, em indivíduos acima dos 18 anos.Para o tratamento da HAS é necessário inicialmente estratificar o risco, definir os objetivos, metas e as condições, mantendo a qualidade de vida.Deve ser dada ênfase ao tratamento não farmacológico, com modificações no estilo de vida e, quando não suficiente, associar o tratamento farmacológico, considerando ainda os casos especiais, como o diabetes mellitus, coronariopatia e insuficiência cardíaca.

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Lead aVR is the only lead in the surface ECG that does not face the "typically" relevant walls of the left ventricle. Historically, its value has been neglected most likely due to its unusual configuration and direction, which appeared to have little correlation with other more congruous and easily diagnostic frontal leads. The isolation of the unipolar leads in the Standard surface ECG presentation may also have played an important role. Even with this "unfair" neglect, we know nowadays that it is very sensitive to locate obstructed epicardial coronary arteries. Besides helping distinguishing the culprit lesion of an infarct, lead aVR also helps recognizing other conditions that could be of clinical significance such as pericarditis, Brugada syndrome, fascicular blocks of the right branch, ectopic left atrial rhythms, etc. The purpose of this review is to revise the clinical value of lead aVR in the recognition of frequent and not so frequent clinical conditions.

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BACKGROUND: Urban air pollutants are associated with cardiovascular events. Traffic controllers are at high risk for pollution exposure during outdoor work shifts. OBJECTIVE: The purpose of this study was to evaluate the relationship between air pollution and systemic blood pressure in traffic controllers during their work shifts. METHODS: This cross-sectional study enrolled 19 male traffic controllers from Santo André city (São Paulo, Brazil) who were 30-60 years old and exposed to ambient air during outdoor work shifts. Systolic and diastolic blood pressure readings were measured every 15 min by an Ambulatory Arterial Blood Pressure Monitoring device. Hourly measurements (lags of 0-5h) and the moving averages (2-5h) of particulate matter (PM(10)), ozone (O(3)) ambient concentrations and the acquired daily minimum temperature and humidity means from the São Paulo State Environmental Agency were correlated with both systolic and diastolic blood pressures. Statistical methods included descriptive analysis and linear mixed effect models adjusted for temperature, humidity, work periods and time of day. RESULTS: Interquartile increases of PM(10) (33 µg/m(3)) and O(3) (49 µg/m(3)) levels were associated with increases in all arterial pressure parameters, ranging from 1.06 to 2.53 mmHg. PM(10) concentration was associated with early effects (lag 0), mainly on systolic blood pressure. However, O(3) was weakly associated most consistently with diastolic blood pressure and with late cumulative effects. CONCLUSIONS: Santo André traffic controllers presented higher blood pressure readings while working their outdoor shifts during periods of exposure to ambient pollutant fluctuations. However, PM(10) and O(3) induced cardiovascular effects demonstrated different time courses and end-point behaviors and probably acted through different mechanisms.

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