Sistema para el cómputo del índice de aumentación y del intervalo de tiempo entre picos sistólicos y diastólicos. ¿es útil en el diagnostic del síncope vasovagal?

Abstract

A friendly application to compute AI (augmentation index) and TI (Time Interval between systolic and diastolic peaks) series from continuous arterial pressure signals, is presented. To obtain these signals a radial tonometry monitor was used. The waveforms were digitized and processed to extract characteristic points. For each of these points, the corresponding magnitude and time of occurrence were recorded. These points are the DBP (diastolic blood pressure), the SBP (systolic blood pressure), the dicrotic notch and the diastolic peak. For this task a computer algorithm to be used with the analog output of the pressure monitor was developed. An early algorithm, upgraded to include the detection of the dicrotic notch and the diastolic peak was used. Usually IA and TI are used as early markers of incremented arterial stiffness. Arterial pressures are synchronized averaged to obtain only one beat, to which both values are calculated. In our approach we first obtain these parameters for each cardiac cycle, and then we compute the mean for each series. Finally the system is used to verify a very interesting hypothesis from others authors: that AI and TI could be used as discriminating features to separate SVV (vasovagal syncope) patients from normal controls. © Springer-Verlag Berlin Heidelberg 2007.