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Temos, urgentemente, que mudar mentalidades. Neste sentido irei apenas abordar dois conceitos fundamentais: 1. a falibilidade das estratégias de avaliação médico-desportiva; 2. a eficácia das manobras de reanimação em casos de paragem cardíaca súbita... Mesmo que por hipótese as estratégias de identificação de portadores assintomáticos de AnCV-ar fossem infalíveis, a possibilidade rara da ocorrência de PCS por fibrilação ventricular em casos de traumatismo da área precordial, a chamada commotio cordis, obrigar-nos-ia a refletir sobre a obrigatoriedade de planear as medidas de suporte básico de vida e o uso do desfibrilador automático externo (DAE) nos recintos e espaços desportivos... Organize ou ajude a implementar a estratégia de avaliação médico-desportiva e os programas de DAE em clubes e outros espaços desportivos. É consensual que a avaliação pré- -participação adequada e realizada por clínicos com a necessária diferenciação permite identificar patologias que estão associadas a risco aumentado de morte súbita (MS).1 A sua identificação atempada permitirá depois a adoção das medidas necessárias com vista a mitigar o risco de MS no praticante... Uma resposta pronta e eficaz após uma PCR durante o exercício pode salvar muitas vidas – na literatura as taxas de sobrevivência rondam os 30 a 45%... Seria interessante ver algumas sociedades científicas (ex: Sociedades Portuguesa de Medicina Desportiva e de Cardiologia) e institutos públicos (ex.: INEM, Instituto Nacional de Medicina Legal) unirem esforços para criar um registo nacional de MS no desporto...

This study analyzed the incidence and characteristics of injuries sustained by amateur youth football players in Portugal during season 2015 - 2016.This is an observational descriptive study. We analyzed Portuguese youth football players' injuries over six months of a season. A total of 529 players were divided according to their age in two groups (Under-17 and Under-19). Data on injuries were collected.Throughout all 62 062.0 hours of exposure recorded, 248 injuries were reported in 173 different players. The average incidence of injury was 3.87 (95% CI = 2.81; 4.94) per 1000 hours of football exposure. There was a significantly higher average incidence of injury during matches - 14.22 (95% CI = 10.35; 18.09) per 1000 hours of exposure - when compared to the average incidence of injury during training - 2.06 (95% CI = 1.22; 2.90) per 1000 hours of exposure. This significance was also observed when the comparison was made within each age group. A traumatic mechanism was involved in 76.6% of all the injuries, while overuse was reported in 12.9%. The most common type was the injury that affected muscles and tendons (52.8%). The body location most commonly affected by injuries was the thigh (24.6%).Even though is essential a better characterization of Portuguese athletes of younger age groups such as those discussed in this study, the results of the studied population are in agreement with the existing literature. However, this study provides more information that may be important to better target the Portuguese athletes' training for injury prevention.This study provides descriptive data on injuries developed in a subpopulation of Portuguese amateur youth football players that could represent a focus for future prevention.Introdução: Este estudo foi projetado com o intuito de analisar a incidência e as características das lesões desenvolvidas pelos jovens jogadores portugueses de futebol amador durante a época de 2015 - 2016. Material e Métodos: Trata-se de um estudo observacional descritivo. Foram analisadas as lesões de jovens atletas durante seis meses de uma época. Um total de 529 jogadores foi dividido em dois grupos, atendendo à sua idade (Sub-17 e Sub-19). Os dados foram colectados semanalmente pelo responsável por cada equipa. Resultados: Ao longo de 62 062,0 horas de exposição registadas, foram reportadas 248 lesões em 173 jogadores. A incidência de lesão média foi de 3,87 (95% CI = 2,81; 4,94) por 1000 horas de exposição a futebol. A incidência de lesão média durante os jogos – 14,22 (95% CI = 10,35; 18,09) por 1000 horas de exposição – foi significativamente superior à incidência de lesão média durante os treinos – 2,06 (95% CI = 1,22; 2,90) por 1000 horas de exposição. Esta significância foi também observada quando feita a comparação dentro de cada grupo etário (Sub-17 e Sub-19). O mecanismo traumático esteve envolvido em 76,6% das lesões, enquanto que o mecanismo de sobre-utilização foi causa de 12,9% das lesões. As lesões mais frequentemente observadas foram as que envolveram músculos e tendões (52,8%). A coxa foi a localização mais comum das lesões (24,6%). Discussão: Apesar de ser essencial uma melhor caracterização dos atletas Portugueses de grupos etários mais novos como os abordados neste estudo, os resultados da população estudada vão de encontro ao que existe na literatura mundial. No entanto, este estudo é mais uma fonte de informação que poderá ser importante para melhor direcionar o treino dos atletas portugueses para a prevenção de lesões. Conclusão: Este estudo fornece informação descritiva das lesões ocorridas numa sub-população de jovens jogadores portugueses de futebol amador, podendo representar um foco para futura prevenção.

Introduction: Atrial fibrillation (AF) is the most common sustained arrhythmia in clinical practice and a major cause of morbidity, due to the associated risk of stroke. However, since it is often paroxysmal, it is commonly underdiagnosed and undertreated. Objectives: The primary objective of this prospective study was to determine the prevalence of paroxysmal atrial fibrillation (PAF) in patients aged 40 and above in a population who underwent continuous 24-hour electrocardiographic monitoring. The secondary objectives were to determine the overall prevalence of AF/atrial flutter (AFL) regardless of the type and to compare the population with AF with the general population and patients with PAF with patients with AF. Results: A total of 4843 consecutive patients were analyzed, 58% women, 26.2% aged 70-79 years (n=1269), 25.9% (n=1252) aged 60-69 years, and 19.0% (n=923) aged 50-59 years; the others were aged either >80 years (n=712, 14.7%) or 80 age-groups) (p80 age-groups) (p 80 anos) (p 80 anos (p

Purpose: To analyze whether exercise training conducted at night disturbs sleep and affects nocturnal cardiac autonomic control in high-level female athletes. Methods: A total of 18 high-level female soccer players (mean [SD] age 20.4 [2.1] y) wore actigraphs and heart-rate (HR) monitors during night sleep throughout night training days (n = 8) and resting days (n = 8), for 3 consecutive weeks. This was a longitudinal study that measured internal training load, sleep, nocturnal cardiac autonomic activity, and well-being ratings prior to training sessions. Results: Training load varied across training days (eg, training impulse range, mean [SD]; effect size, ES [95% confidence interval]: 72.9 [18.8] to 138.4 [29.6] a.u.; F4,62 = 32.331; [.001–.16], large effect; P P = .005; moderate effect) and sleep-onset time (00:58 [00:19] h vs 00:44 [00:16] h; ES = 0.802 [0.68–0.94], P = .001; moderate effect) were negatively affected after night training. In addition, small effects were detected for wake-up time, time in bed, and sleep latency (P > .05). No differences were detected in HR variability during sleep (range of lnRMSSD: 4.3 [0.4] to 4.5 [0.4] ln[ms] vs 4.6 [0.3] to 4.5 [0.4] ln[ms]; F3,52 = 2.148; P > .05; [.01–.25], medium effect), but HR during sleep was significantly higher after training days (range of HR: 56 [4] to 63 [7] beats/min vs 54 [4] to 57 [6] beats/min; F2,32 = 15.956; P [.20–.63], large effect). Conclusion: Overall, the results indicate that exercise training conducted at night may disturb sleep and affect HR, whereas limited effects can be expected in HR variability assessed during sleep in high-level female soccer players.

Particularly intense exercise or sports competition may predispose athletes to an increased risk of sudden death or other major heart events. An underlying heart disease is responsible for the majority of sudden deaths in athletes. A cardiac preparticipation evaluation could minimize these events by identifying subjects at risk and not approving those at risk from taking part in competitive sports. The general recommendations for preparticipation screening include a thorough personal and family clinical history and physical examination of the athlete. This screening, complemented when recommended by electrocardiogram, echocardiogram, nuclear magnetic resonance, and genetic testing, should be able to recognize the most important causes of sudden death like hypertrophic cardiomyopathy, that is, the most common cause of sudden death in athletes, Marfan syndrome, arrhythmogenic right ventricular cardiomyopathy or dysplasia, long QT syndrome, preexcitation syndrome, Brugada syndrome or other ion channel diseases, clinically important arrhythmias, and congenital coronary artery anomalies.

Auscultation is currently both a powerful screening tool, providing a cheap and quick initial assessment of a patient’s clinical condition, and a hard skill to master. Acquiring this skill is not only intrinsically difficult but our teaching methods are inadequate due to a variety of practical issues. In this chapter, we will discuss the difficulties of the art of auscultation, how we currently teach this skill and describe a novel simulation technology, IS4Learning, that can be used in three different teaching settings enabling us to train and evaluate students in the art of auscultation.

Sudden cardiac arrest (SCA) and sudden cardiac death (SCD) refer to the sudden cessation of cardiac mechanical activity with hemodynamic collapse, often due to sustained pulseless ventricular tachycardia/ventricular fibrillation. These events mostly occur in patients with evidence for ischemia due to coronary artery disease, disease of the myocardium (due to hypertrophy, fibrosis, scar replacement, or other myocardial abnormality that may or may not have been previously diagnosed), valvular abnormalities, or congenital channelopathies. The event is referred to as SCA if an intervention (e.g., defibrillation) or spontaneous reversion of the heart rhythm restores circulation. The event is called SCD if the patient dies.

Background A 64-year-old male was observed as an outpatient with atypical, non-exercise-induced chest pain and palpitations. He had arterial hypertension and marked concentric left ventricular hypertrophy. After 2.5 years of antihypertensive drug therapy the patient's blood pressure had returned to normal, but his left ventricular hypertrophy was unchanged. Investigations Electrocardiography, transthoracic echocardiography, myocardial perfusion scintigraphic imaging, measurement of α-galactosidase A activity, gene sequencing, brain MRI, carotid artery ultrasonography, biochemical renal evaluation and cardiac Doppler tissue imaging. Diagnosis Cardiac Fabry's disease. Management Losartan, hydrochlorothiazide, low-dose aspirin and bisoprolol. The patient is expected to begin enzyme replacement therapy.

The objective of this study was the assessment of the injuries occurred over the competitive rowing lifetime of Portuguese senior rowers.We sent a questionnaire to all Portuguese senior rowers medalled in the national championships during the 2013-2014 season. We analysed biometric variables, anatomic location, type and circumstances of injury occurrence, type of treatment provided and time of inactivity. For statistical analysis we used parametric and non-parametric statistics with 95% confidence levels (p0.05).The questionnaire was answered by 18 of the 18 female and 74 of the 77 male rowers. Females had significantly lower ages, heights and weights and rowed more often sculling boats (p0.05). The number of years of practice, as well as the number of injuries per rower was similar, for both females and males. The mean age at the first injury was significantly lower in females (p0.001), who also had more progressive lesions than acute ones, although not significantly. In both, the most frequent anatomical location and type of injury were the lumbar region and muscular pathology, with a higher occurrence in winter and spring, during land training. Femalessustained longer periods of inactivity, but not significantly.The results that were different from those reported by other authors may be related with differences in the studied populations or with other factors that need to be clarified.The injuries sustained by the Portuguese competitive rowers, probably associated with a lower competitive exposure of our athletes, were less severe than those generally reported in the literature.Introdução: O objetivo deste estudo foi a avaliação das lesões ocorridas ao longo da vida desportiva de remadores de competição seniores portugueses. Material e Métodos: Enviámos um questionário a todos os remadores seniores medalhados nos campeonatos nacionais na época de 2013-2014. Analisámos variáveis biométricas, localização anatómica, tipo e circunstâncias de ocorrência de lesões, tratamentos efetuados e tempos de inatividade. Para análise estatística utilizámos métodos paramétricos e não paramétricos com níveis de confiança de 95% (p0,05). Resultados: Responderam 18 dos 18 remadores femininos e 74 dos 77 masculinos. Os femininos apresentaram idades, estaturas e pesos significativamente mais baixos e remaram mais parelhos (p0,05). O número de anos de prática e de lesões por remador foram semelhantes, entre femininos e masculinos. A idade média da primeira lesão foi significativamente mais precoce nos femininos (p0,001), nos quais se registaram mais lesões progressivas do que agudas, embora de forma não significativa. Tanto nos femininos como nos masculinos, a localização anatómica e o tipo de lesão mais frequentes foram a região lombar e a contratura muscular, com maior ocorrência no inverno e na primavera, em terra, durante os treinos. A inatividade por lesão foi superior nos femininos, embora de forma não significativa. Discussão: Os resultados que diferiram dos reportados por outros autores podem estar relacionados com diferenças nas populações estudadas ou com outros fatores que necessitam de ser esclarecidos. Conclusão: As lesões dos remadores de competição portugueses, associadas provavelmente a um nível competitivo menos expressivo dos nossos atletas, foram menos graves do que as geralmente referidas na literatura.

Autonomic dysfunction seems to play a central role in the pathophysiology of neurocardiogenic syncope (NCS) but conflicting data have recently become available. We evaluated autonomic nervous system (ANS) function (heart rate variability (HRV), systolic blood pressure variability (SBPV) and baroreceptor gain (BRG)) and non-invasive haemodynamics (cardiac output and total peripheral resistance) in patients with neurocardiogenic syncope. Retrospectively, we evaluated 12 NCS patients (positive head-up tilt without pharmacological provocation) in the basal state and at initial tilt, 12 non-NCS patients with tilt-negative syncope and 12 aged-matched normal controls. Prospectively, we evaluated 16 NCS patients to analyse the haemodynamics and ANS activity throughout the tilt test (beginning of tilt and before syncope occurs). HRV and SBPV were accessed by fast Fourier transforms (FFT) and spontaneous BRG by temporal sequences, slope and a index. Modelflow was used to quantify the non-invasive haemodynamics. None of the autonomic and haemodynamic parameters at baseline or in the first 10 min of tilt was different among the respective NCS, non-NCS syncope and normal control groups, except for SBP, which was higher at baseline in controls. Throughout the tilt test in the prospective NCS group, the heart rate increased (88-95 beats x min(-1), P

Abstract —To clarify the role of the sympathetic nervous system in the development of cyclosporine A (CsA)-induced rise in blood pressure (BP), the effects of CsA on 24-hour ambulatory BP (ABP) were studied in patients with familial amyloid polyneuropathy (FAP) who underwent a liver transplantation. On the basis of autonomic function tests, patients with absent or mild-to-moderate sympathetic damage (Group A, n=11, age 29 to 43 years, disease duration 2 to 6 years) and patients with severe sympathetic damage (Group B, n=9, age 27 to 38 years, disease duration 3 to 9 years) were identified. Both groups were followed for 1 year. The daily doses of CsA and the CsA whole blood trough levels between the groups did not differ. Pretransplantation values of daytime and nighttime ABP were, respectively, 117±8/76±7 mm Hg and 108±12/68±9 mm Hg in group A and 107±6/66±4 mm Hg ( P P P

Disabling orthostatic hypotension, due to insufficiency of the autonomic nervous system, is a common complication of type I familial amyloidotic polyneuropathy (FAP). We investigated whether oral treatment with L-threo-3,4-dihydroxyphenylserine (L-threo-Dops), a noradrenaline precursor, might be of therapeutical benefit. In twenty untreated FAP patients, aged 33 to 44 years, who, because of severe orthostatic hypotension, were bedridden or constrained to a sitting life, supine and erect blood pressure (BP), plasma noradrenaline and tilting time, defined as the interval (s) between the beginning of a 60 degrees head-up tilt and the occurrence of orthostatic symptoms (dizziness, blurred vision or near syncope) were determined before and at repeated intervals during oral treatment with L-threo-Dops, 100 mg bid, for 6 months. Before treatment supine mean BP was 80 (76-85) mmHg (mean and 95% CI), supine plasma noradrenaline was low, 59 (41-77) pg/ml and tilting time ranged from 38 to 118 s. In response to tilt, mean BP immediately fell by 36 (31-41) mmHg, whereas plasma noradrenaline increased by only 11 (0-21) pg/ml (p = 0.05). After 3 to 5 days of treatment with L-threo-Dops all patients experienced marked improvement of their orthostatic tolerance as reflected by their ability to walk freely around. This effect sustained throughout the six months of treatment. Plasma noradrenaline increased moderately by 37 (11-63) pg/ml (p = 0.02) and supine mean BP increased by 8.6 (5.8-12.4) mmHg (p0.001) during chronic treatment. Supine or nocturnal hypertension did not develop, the fall in mean BP in response to tilt diminished by 12.5 (6.5-17.3) mmHg (p0.001) and tilting time became longer than 600 s in all patients. Because of its efficacy, its sustained duration of action and the lack of side effects, L-threo-Dops is advocated to improve orthostatic tolerance in patients with autonomic insufficiency due to FAP.

The sensitivity and specificity of heart rate variability (HRV) in the corroboration of brain death diagnosis in patients with acute traumatic intracranial lesions was evaluated in 20 patients with clinical criteria of brain death, nine patients in deep coma (Glasgow scale

Background Sports pre-participation cardiovascular screening remains a challenging topic, without consensus amongst the scientific community. Sports pre-participation cardiovascular screening with electrocardiogram (ECG) is not systematically included in the United States of America. However, in some European countries both ECG and echocardiogram are requested. These asymmetric proceedings are related with the ongoing discussion on health-related benefits effectiveness and costs. Objective Define the proportion of cardiovascular screening exams which require complementary cardiovascular exams in addition to the routine electrocardiogram performed by the athletes. Moreover, it was intended to analyze the influence of the complementary cardiovascular exams results' in the decision making for medical clearance. Design Retrospective cohort study. Setting Nonprofessional to elite athletes. Patients (or Participants) Between 2014 and 2015, a total of 862 athletes performed sports pre-participation cardiovascular screening. Interventions (or Assessment of Risk Factors) All the athletes underwent a cardiovascular screening, including medical history, physical examination and 12-lead electrocardiogram. In case of cardiovascular diseases suspicion, complementary cardiovascular exams (echocardiogram and cardiac stress test) were solicited. Main Outcome Measurements As main outcomes were considered the need for complementary cardiovascular exams according the Seattle criteria (%), presence of abnormalities in these complementary cardiovascular exams (%) and decision for medical clearance (%). Results From the 862 athletes, 54 (6%) required complementary cardiovascular exams, of which 8 (0.9%) showed abnormal cardiovascular findings. Three athletes (0.3%) did not get medical clearance to participate in sports. Conclusions The sports pre-participation cardiovascular screening with ECG required complementary cardiovascular exams in 6% of the cases and 0.3% were not cleared to participate in sports. The decision was based in the most up-to-date knowledge of life threatening cardiac clinical conditions and supports a life-preventive measure to 3 young persons over an approximate cost of 12000€., info:eu-repo/semantics/publishedVersion

Mean hourly parameters obtained from all beats (long series) were compared with those obtained from a sample of 512 beats extracted each hour (short series) in nine presumably normal subjects. For both the short and long series, the spectral components, very low frequency, (VLF), low frequency (LF), and high frequency (HF), and time-domain indices (such as the Ewing statistic [PNN50] and RR standard deviation [SD-RR]), have been estimated. The spectral components LF and HF, estimated from the short and long series, were not significantly different, whereas significant differences were found between VLF, SD--RR, and PNN50. In both the short and long series, a strong correlation was found between LF and SD-RR and between HF and PNN50. The results suggest that, over a period of 24 hours, hourly LF and HF spectral components can be obtained using a single series of 512 beats every hour, with a great advantage over the evaluation of the mean hourly parameters. This method would be particularly useful in the study of circadian heart rate spectral analysis in Holter recordings with multiple artifacts or ectopic beats, and in general, when analysis of the entire 24-hour series is not feasible.

Heart rate variability (HRV) data display non-stationary characteristics and exhibit long-range correlation (memory). Detrended fluctuation analysis (DFA) has become a widely-used technique for long memory estimation in non-stationary HRV data. Recently, we have proposed an alternative approach based on fractional integrated autoregressive moving average (ARFIMA) models. ARFIMA models, combined with selective adaptive segmentation may be used to capture and remove long-range correlation, leading to an improved description and interpretation of the components in 24 hour HRV recordings. In this work estimation of long memory by DFA and selective adaptive ARFIMA modelling is carried out in 24 hour HRV recordings of 17 healthy subjects of two age groups. The two methods give similar information on long-range global characteristics. However, ARFIMA modelling is advantageous, allowing the description of long-range correlation in reduced length segments.

Long-term heart rate variability (HRV) series can be described by time-variant autoregressive modelling. HRV recordings show dependence between distant observa- tions that is not negligible, suggesting the existence of long-range correlations. In this work, selective adaptive segmentation combined with fractionally integrated auto- regressive moving-average models is used to capture long memory in HRV recordings. This approach leads to an improved description of the low- and high-frequency components in HRV spectral analysis. Moreover, it is found that in the 24-h recording of a case report, the long-memory parameter presents a circadian variation, with different regimes for day and night periods.

In this paper, we present a multimedia system named BioBeAMS (Bio-signal Behavior Attachment Multimedia System) for assessment of attachment organizations and heart rate in a strange situation experimental procedure for a mother to child attachment study (a well known psychological procedure). Attachment patterns assessed through this procedure have been conceived as different strategies to regulate the access to relevant attachment information and to process distress-related information. The psycho-physiological activation led by emotional processing of attachment experiences during the strange situation procedure may be a critical factor for understanding the subject's psychological attachment strategies. BioBeAMS is an application which integrates bio-signals, video/audio of the psychological experimental procedure and the rater's coding, running in the MS Window 95 environment on a PC. Using this system, we can acquire ECG signals and capture video and audio in a synchronous way. It also enables the raters to subsequently analyze and evaluate psychological and physiological events during review to study possible relations.

The objective of this study was to assess the influence of day-night cycle and sleep-awake period on the circadian pattern of heart rate variability (HRV). Twelve male oil refinery security shift workers, aged 39 +/- 7 years, were studied with 24-hour Holter monitor recordings during morning and night work periods. Hourly HRV parameters in the time and frequency domains were evaluated. For both shifts, all HRV parameters during awake or work periods were found not to be statistically different. In both day and night work shifts, the very low frequency and high-frequency components of HRV and the proportion of differences in successive R-R intervals greater than 50 ms increased during the sleep period, while the low frequency/high frequency ratio decreased. The low-frequency component in absolute units and the SD of the R-R interval did not show any variation in either shifts for the different periods. These results suggest that the circadian pattern of HRV seems to be predominantly related to sleep (supine) and wakefulness (standing) and remains independent of night-day cycle.

Spectral analysis of R-R variability has been done in twenty subjects with Familial Amyloidotic Polyneuropathy in order to define intensity, chronology and discriminative capacity of this method in parasympathetic and sympathetic disturbances. The subjects were subdivided in 3 groups. Group I with far advanced disease, group II in early stages of the disease and group III with asymptomatic carriers. The R-R spectral analysis was calculated after fast Fourier transform in supine and after 60 tilt. Valsalva manoeuvre, deep breathing and standing were performed in groups II and III. The results showed a very severe autonomic disturbance in group I.The parasympathetic system seems to be early affected even in some asymptomatic carriers. Heart rate spectral analysis seems to be more sensitive for detection of autonomic disturbances than other autonomic tests.

This report presents a well-documented link between vasodepressor syncope, 5 a marked increase of LFHF ratio response to orthostasis (sympathetic dominance), 6 and the efficacy of β blockers in preventing orthostatic symptoms and absence of tilt-induced syncope, 5 with normalization of the LFHF ratio response.

In order to assess the natural history of asymptomatic Wolff-Parkinson-White (WPW) syndrome, 25 sportsmen aged 27.6 years (range 15–44 years) with a WPW pattern on the ECG have been studied. In all cases, a history was taken, along with a complete physical examination, ECG and M-mode echocardiogram (since 1978) in order to exclude concurrent heart disease. Patients were seen at least once annually at our center. On at least one occasion a maximal exercise tolerance test and a 24-h Holter monitoring were performed, and in 13 subjects, the ajmaline test was carried out.

Orthostatic intolerance is the development of disabling symptoms upon assuming an upright posture that are relieved partially by resuming the supine position. Postural tachycardia syndrome (POTS) is an orthostatic intolerance syndrome characterized by palpitations because of excessive orthostatic sinus tachycardia, lightheadedness, tremor, and near-syncope. Patients usually undergo extensive medical, cardiac, endocrine, neurologic, and psychiatric evaluation, which usually fails to identify a specific abnormality. The authors investigated the autonomic and hemodynamic profile of patients with POTS and the effectiveness of bisoprolol and fludrocortisone. The authors evaluated 11 female patients with POTS before and after medical treatment with a cardioselective bisoprolol beta-blocker or fludrocortisone, or both, and 11 age-matched control patients. Variability of heart rate and systolic blood pressure was assessed by fast Fourier transform, and spontaneous baroreceptor gain was assessed by use of the temporal sequences slope and alpha index. Modelflow was used to quantify hemodynamics. Symptoms in all patients improved greatly after medication. The autonomic and hemodynamic impairment observed in patients with POTS, particularly after orthostatic stress, is treated effectively with bisoprolol or fludrocortisone or both. These results need further confirmation in a controlled double-blind study. Proper medical treatment improves dramatically the clinical and autonomic-hemodynamic disturbances observed in patients with POTS. The data support the hypothesis that POTS is the result of a hyperadrenergic activation or hypovolemia during orthostasis.

Neurocardiogenic syncope seems to be the most common cause of syncope. It is believed to be triggered by paradoxical autonomic reflexes, beginning in the ventricular mechanoreceptors of the heart, modulated by the brain stem and terminating in the autonomic efferent pathways (parasympathetic stimulation with bradycardia or asystole and sympathetic inhibition with severe hypotension). Tilt test has been used recently, as a safety and effective tool to identify subjects prone to syncope. Although the pathophysiology of this syndrome is not completely understood, pharmacological therapeutics seems very effective in resolving symptoms.

Physical activity is the basic factor to the human being in order to assume his place in society. Blind persons are often sedentary, which compromises its physical capacity. The present work evaluates the blind person's physical capacity, analysing possible differences related to sex, age and life time blindness. The sample was constituted by 27 blind (congenital and noncongenital), 18 male and 9 female, aged between 17 and 37 years old. To evaluate previous physical activity, a questionnaire, was answered which showed a dominant sedentary population. The maximum oxygen uptake was determined in a treadmill test using standard procedures (Bruce protocol). Medium results for boys were 45.85 +/- 8 ml/kg/min and for girls were 34.46 +/- 3.8 ml/kg/min. The difference between congenital and acquired blindness on the VO2max values was 2.9 ml/kg/min, not statistically significant (p = 0.468). Those findings lead us to consider that aerobic capacity mostly depends on type and intensity of physical exercise which may be temporary related to the onset of blindness and visual impairment degree.

The objectives of the study were to characterize power spectrum pattern of the heart rate variability and assessment of the relative contributions of sympathetic and parasympathetic cardiac nervous system control in athletes. Thirty-three male athletes, swimming (1), canoeing (10), cycling (6), athletics (4), football (3), roller-skating (2) and volleyball (7) aged 23.4 +/- 5.5 years, with a mean athletic level of 18 hours/week (8-45) and 33 sedentary healthy control subjects were included. Ecg signals were recorded after a period of 15 minutes in supine rest with controlled breathing at 15 cycles/min. Signal acquisition was done at 300 samples/sec. From 512 consecutive heart beats, we calculated mean average, standard deviation, maximum and minimum R-R intervals and, after computing the fast Fourier transform, total spectrum power, low frequency (LF), high frequency (HF) components and its ratio (LF/HF). The average R-R interval was 987.7 +/- 168.8 ms and 762.7 +/- 125.3 ms, the variance was 5.44 and 2.51 ms2 and ratio of R-R interval maximum/minimum (E/I ratio) 1.53 +/- 0.16 and 1.41 +/- 0.16, respectively for athletes and control group. Differences between groups were significant (p0.01) for all parameters, with higher variability in the athletes. Both spectral bands (LF and HF) had higher power in athletes (LF = 925 +/- 920 and HF = 2258 +/- 2349 ms2) than in the control group (LF = 442 +/- 446 and HF = 1179 +/- 1542 ms2) (p0.01). There were no significant differences for LF/HF ratio, or normalized LF (LF%) or normalized HF (HF%) between groups.(ABSTRACT TRUNCATED AT 250 WORDS)

The signal-averaged ECG became an important noninvasive method for identifying life-threatening ventricular arrhythmias. It is most accurate in patients with coronary artery disease and can be helpful in predicting whether a patient with an unexplained syncope or nonsustained VT is at risk of developing sustained ventricular tachycardia or not. A patient with an entirely normal signal-averaged ECG is at very low risk of sustained VT. In contrast, an abnormal signal-averaged ECG should raise suspicion about VT, and prompt further studies, including electrophysiological testing. Signal-averaged ECG can also be used repeatedly with acceptable reproducibility. Technological advances and improvements in the frequency analysis of the averaged signal may increase the predictive accuracy of the technique and consequently enhance its clinical applications.