Poincare Mapping: A Potential Method for Detection of T-wave Alternans

T wave alternans (TWA)at microvolt level is recognized as an important marker to predict sudden cardiac death and several methods are used to measure the variation of T-wave morphology. The purpose of this study is to assess the accuracy and effectiveness of Poincare mapping(PM) which is a method based on nonlinear dynamics in detection of TWA. Sample series selected from ECG were used to draw the Poincare maps from which we can get the different shapes and quantitative measures, alternans distance (Dtwa).At the same time, these sample series were assessed by the spectral method(SM) and alternans voltage (Vtwa) was obtained. Then the two kinds of measures were compared by linear regression and the correlation coefficient was γ=0.984 which showed the significant correlation between them. The value of Dtwa>20uv was accepted as a level determinative for presence of TWA. The Poincare mapping was useful and potential for the detection of TWA.