Los primeros días de la actividad electrodérmica

Este artículo enfatiza las etapas principales del descubrimiento de uno de los marcadores autonómos más destacados de las expresiones mentales, la actividad electrodérmica (EDA). La contribución de las escue-las de fisiología francesa y alemana, orientada por las necesidades clínicas y el deseo de conocer más sobre los mecanismos fisiológicos, constituyen las primeras raíces de dicha actividad. En este marco, Féré y Tarchanoff, des-cubridores franceses y rusos respectivamente, establecieron el vínculo entre la actividad mental y la EDA, por un lado, y sentaron las bases metodoló-gicas de la utilización moderna de este neuromarcador, por el otro. Este le-gado, asociado con medidas neuronales centrales, promete un futuro en expansión en neuropsicología, psicopatología, neurología, criminología y en neurociencia cognitiva y afectiva. This paper emphazises main steps of the discovery of one of the most salient autonomic markers of mind expressions, the electrodermal ac-tivity(EDA). The contribution of French and German schools of physiol-ogy, aimed by clinical needs and the desire to know further about physio-logical mechanisms, constitutesthe very early roots of such activity. In this frame, Féré and Tarchanoff, respectively a French and a Russiandiscover-ers, established the link between mind activity and the EDA on the one hand and laid the methodological foundations of modernutilisation of this neuromarker on the other hand. This heritage, associated with central neu-ral measures, is promised to an expanding future in neuropsychology, psy-chopathology, neurology, criminology and in cognitive and affective neu-roscience.

The autonomic cardiac nervous system and arrhythmogenesis: risk stratification in the foreseeable future

Both experimental and clinical studies have shown that the autonomic nervous system plays an important role in arrhythmogenesis. Many methods describing cardiovascular autonomic regulation have been developed and tested for use as predictors of arrhythmic and other cardiovascular events. The majority of studies have focused on patients with known cardiac disease, such as prior myocardial infarction or congestive heart failure. All-cause mortality, as well as non-sudden and sudden cardiac death have been used as main endpoints. Sudden cardiac death has often been considered to be equivalent to arrhythmic cardiac arrest. Despite promising results in this field, markers of the autonomic nervous system are still not routinely used in clinical practice, mainly due to the fact that measurement of these markers does not result in evidence-based therapeutic implications. There is still a lack of randomized trials using autonomic markers as pre-defined variables in selecting patients for the studies, which would have yielded results that an intervention reduces the arrhythmic or other endpoint in those with abnormal or impaired autonomic regulation. Hence, at present, the possible use of autonomic assessment in predicting life-threatening arrhythmias is restricted to individual cases at the borders of intervention guidelines.

Sudden death: Neurogenic causes, prediction and prevention

Sudden death is a major health problem all over the world. The most common causes of sudden death are cardiac but there are also other causes such as neurological conditions (stroke, epileptic attacks and brain trauma), drugs, catecholamine toxicity, etc. A common feature of all these diverse pathologies underlying sudden death is the imbalance of the autonomic nervous system control of the cardiovascular system. This paper reviews different pathologies underlying sudden death with emphasis on the autonomic nervous system contribution, possibilities of early diagnosis and prognosis of sudden death using various clinical markers including autonomic markers (heart rate variability and baroreflex sensitivity), present possibilities of management and promising prevention by electrical neuromodulation.

Reprodutibilidade do teste de caminhada de 6 minutos e marcadores autonômicos cardíacos em idosas ativas e sedentárias

DOI: http://dx.doi.org/10.5007/1980-0037.2016v18n3p287 The aim of this study was to examine the reliability of the 6-minute walk test (6MWT) and post-exercise cardiac autonomic markers in physically active and sedentary older women. Eighteen physically active older women (64.2±3.1 years; 63.0±2.7 kg; 1.52±0.06 m; 26.9±2.7 kg.m-2) who performed Tai Chi Chuan for at least 6 months, and 18 sedentary older women (64.0±3.7 years; 63.8±8.9 kg; 1.49±0.05 m; 28.4±3.5 kg.m-2) were submitted to 6MWT in two separate occasions. Immediately after 6MWT, heart rate recovery at one (HRR1’) and two minutes (HRR2’), as well as the heart rate variability (HRV) were recoded. Reliability was verified by intraclass correlation coefficient (ICC) with 95% confidence interval, Bland-Altman plots were used as a measure of agreement, and coefficient of variation (CV) was calculated. High reliability (ICC=0.86) was found for performance in 6MWT (528.8 ± 71.4 m and 473.2 ± 62.4 m; CV=7.9 and VC=8.5%) in both groups. Likewise, high reliability (ICC≥0.84 and ICC≥0.80) was found for HRR 1’ (29.0±11.0 bpm and 17.0±8.0 bpm; VC=30.1% and VC =40.2%) and HRR 2’ (36.0±10.0 bpm and 24.0±9.0 bpm; VC =23.7% and VC =22.8%) in both groups. Regarding HRV, moderate reliability was found in the active group (CCI≥0.57; VC =35-47%), while moderate-high reliability was found in the sedentary group (CCI=0.65-0.76; VC=34-69%). Agreement was found for all variables analyzed. In conclusion, post-exercise 6MWT, HRR, and HRV are reliable tools to assess functional capacity and cardiac autonomic control in physically active and sedentary older women.