Dynascope: a software tool for the analysis of heart rate variability during exercise

Heart Rate Variability is usually studied using spectral analysis in stationary conditions, but this kind of study cannot be applied during exercise tests where stationarity decays. To study dynamic situations a software tool has been designed to evaluate HR changes during non stationary conditions. We introduce DynaScope a Windows-based C++ software containing algorithms developed to analyse RR variability where spectral analysis cannot be applied

The association of spatial T wave axis deviation with incident coronary events. The ARIC cohort

BACKGROUND: Although current evidence suggests that the spatial T wave axis captures important information about ventricular repolarization abnormalities, there are only a few and discordant epidemiologic studies addressing the ability of the spatial T wave axis to predict coronary heart disease (CHD) occurrence. METHODS: This prospective study analyzed data from 12,256 middle-aged African American and white men and women, from the Atherosclerosis Risk in Communities Study (ARIC). Following a standardized protocol, resting standard 12-lead, 10-second electrocardiograms were digitized and analyzed with the Marquette GE program. The median follow-up time was 12.1 years; incident coronary heart disease comprised fatal and non-fatal CHD events. RESULTS: The incidence rate of CHD was 4.26, 4.18, 4.28 and 5.62 per 1000 person-years respectively, across the spatial T wave axis quartiles. Among women for every 10 degrees increase in the spatial T wave axis deviation, there was an estimated increase in the risk of CHD of 1.16 (95% CI 1.04–1.28). After adjustment for age, height, weight, smoking, hypertension, diabetes, QRS axis and minor T wave abnormalities, this hazard rate ratio for women fell to 1.03 (0.92–1.14). The corresponding crude and adjusted hazard ratios for men were 1.05 (95% CI 0.96–1.15) and 0.95 (0.86–1.04) respectively. CONCLUSIONS: In conclusion, this prospective, population-based, bi-ethnic study of men and women free of coronary heart disease at baseline shows that spatial T wave axis deviation is not associated with incident coronary events during long-term follow up. It is doubtful that spatial T wave axis deviation would add benefit in the prediction of CHD events above and beyond the current traditional risk factors

Miłość jako teologiczne i filozoficzne pojęcie w koncepcji Jana Pawła II

Humankind has been asking the questin about love during the ages. John Paul II took up the theme of Christian love in depth and based it on the theology of body. Pope brought back its real significance by relating this meaning to the betrothal love between woman and man. In his philosophy person is not a means to an end but an end in itself. This love is marked by the common aim, which biases couple in favour of marriage

HeartScope : a software tool addressing autonomic nervous system regulation

The evaluation of cardiovascular control system requires ad-hoc software tools specifically designed to address the complexity of the regulation mechanisms in a multiparametric and multidisciplinary perspective. We introduce HeartScope a Windows-based C++ tool that brings together the most advanced signal processing methods for the analysis of cardiovascular regulation in a flexible and friendly framework

Proof of concept for an international long-time preservation ECG format

We present a proof-of-concept of a medical data format for storing and retrieving 12-lead, 10-second standard electrocardiograms (ECG). The new format combines a digital ECG record into a standard graphical report (PDF). Using the very recent PDFIA-3 standard (ISO 19005-3:2012), we designed a long-term preservation graphic report (such as a standard 3 74 or 6 72 ECG printout) in which the original ECG digital data (using the aECG ANSIIHL7 R1-2004 format) is embedded as a compressed attachment. The proposal also includes two wcrys of ensuring conformity between the ECG vector images and the digital data. First, a digital signature is added to guarantee that the document was not modified after creation. Second, specific metadata are inserted to allow a direct digital comparison between the vector ECG printout and the data. To prove the feasibility of the approach, 93 aECGs, selected from different device manufacturers, resolutions and sample rates, were converted into the new format and then validated. Differences between digital data and vector graphics were alwcrys smaller than 0.02 \u3bcV, significantly below the typical AID converter resolution

Assessing autonomic response to repeated bouts of exercise below and above respiratory threshold : insight from dynamic analysis of RR variability

Purpose: The dynamics of vagal withdrawal and reactivation during pulses of exercise are described by indices computed from heart period (RR) variations, which may be sensitive to duration and load. We sought to assess the consistency over time of these indices, which is not well established. Methods: We recorded continuous electrocardiogram during series of five successive bouts (2 min) of submaximal exercise (at 40 and 70 % of VO2peak, different days). Autonomic responsiveness was inferred from quantification of onset and offset of RR dynamics of each individual bout. Consistency of results was assessed with intraclass correlation (ICC). Results: During exercise bouts, indices from tachycardic and bradycardic transients reach lower levels in response to higher exercise loads and progression of exercise. There is a significant effect of load and time (i.e., bout repetition) for all examined variables, with a clear interaction. However, no interaction is observed with the 60 s change in heart rate. ICC analysis demonstrates that various indices are characterized by large differences in stability, which is generally greater within the same day (e.g., tachyspeed ICC at 40 % = 0.751, at 70 % = 0.704, both days = 0.633; bradyspeed, respectively, = 0.545, 0.666, 0.516). Conclusions: Intensity and duration of exercise modulate vagal withdrawal and reactivation. Analysis of RR variations, during successive brief exercise bouts at lower and higher intensity, ensures a consistency similar to that reported for autonomic cardiac regulation at rest and might guide the choice among multiple indices that are obtained from the tachogram. \ua9 2014 Springer-Verlag Berlin Heidelberg