Detection of T-Wave Alternans Based on the Maximum of T Waves

T-wave alternans (TWA) is a variation in the amplitude or morphology of the T wave of the beat-to-beat ECG which provides a noninvasive and clinically useful marker for the risk of sudden cardiac death (SCD) caused by life threatening arrhythmias. Detection of beat-to-beat microvolt fluctuation of the T wave has been made possible with the use of advanced signal processing techniques and high-resolution electrodes to reduce ambient noise. Traditional spectral analysis of TWA needs precise positioning, in this paper, an algorithm based on the maximum of T waves is proposed. Using the method can reduce sample rate, which means the amount of calculation can be reduced, and can solve the problem that the fixed T-wave sampling points can´t change along with the change of heart rate. A time series of 128 amplitudes of corresponding points on the T wave are processed by fast Fourier transformation (FFT) to yield the spectral display with the various peaks. The result shows that the proposed algorithm has a high detection quality and greatly reduces the amount of calculation.