TITLE:
On the basis of the morphology of the T-wave alternans: A Poincare mapping method research
AUTHORS:
Hui Guo, Jie Zhao, Fei Li, Tiantian Li
KEYWORDS:
T-Wave Alternans; Poincare Mapping Method; Spectral Method; Vector Angle Index (VAI)
JOURNAL NAME:
Journal of Biomedical Science and Engineering,
Vol.6 No.4,
April
29,
2013
ABSTRACT: Presently
T-wave alternans (TWA) has become a clinical index of non-invasive diagnosis
for heart sudden death prediction, and detecting T-wave alternate accurately
is particularly important. This paper introduces an algorithm for detecting
TWA using Poincare mapping method which is a technique for nonlinear dynamic
systems to display periodic behavior. Sample series of beat to beat cycles were
selected to prepare Poincare mapping method.
Vector Angle Index (VAI), which is the mean of the difference between θi (the angle between the line connecting the i point to the origin and the X axis)
and 45 degrees was used to present the presence or absence of TWA. The value of
0.9 rad ≤ VAI ≤ 1.03 rad is accepted as a level determinative for presence of
TWA. VAI via Poincare mapping method (PM) is used for correlation analysis with
T-wave alternans voltage (Vtwa)
by way of the spectral method (SM). The cross-correlation coefficient between Vtwa and VAI is γ = 0.8601. The algorithm can identify
the absence and presence of TWA accurately and provide idea for further study
of TWA-PM.