Microvolt T-wave alternans analysis using Lyapunov exponents

T-wave alternans (TWA) is a marker of cardiac instability and high risk of sudden cardiac death. In this paper we propose a new approach for the TWA detection. For this purpose Lyapunov spectrum was calculated from T-wave time series. To evaluate the detector performance, simulated T-waves based on the real ECG signals were used. Detected and simulated episodes were compared, in terms of sensitivity and positive predictivity. The results show that this method can reliably detect T-wave alternans episodes.