Effects of aging on the autonomic modulation of the ventricular repolarization dispersion

PABLO DANIEL CRUCES; MARÍA PAULA BONOMINI; MARCOS JAVIER TEPERINO; PEDRO DAVID ARINI

San Nicolás

Congreso; XX Congreso Argentino de Bioingeniería; 2015

UTN Regional San Nicolás

The study of ventricular repolarization dispersion (VRD) is of relevant concern in cardiacpathophysiology. However, the high number of physiological variables involved makes the originof the VRD remains incompletely understood. We have analyze how aging influences theautonomic modulation of VRD in response to postural changes. Through a Tilt-Test we haveinduced abrupt postural changes to young and middle-aged healthy subjects and have studiedthe evolution of several dispersion markers: Duration ones, based on electrocardiogram intervals;energy ones, developed through a Principal Components Analysis (PCA) in T-wave; and themorphology one, extracted feature from an absolute T-wave. In both groups, results have shownsignificant decreases in early repolarization. Moreover, we have found significant decreases intotal, early and late repolarization energy, and in the T-wave amplitude. In another sense,we have observed that the repolarization energy obtained by PCA jointly with early T-waveslope and amplitude have been able to reflects VRD differences between young and middle-agedsubjects. Finally, this work provides the range of values for VRD in normal conditions whichmay contribute to the design of an optimal cardiac risk marker.