Time-frequency analysis and linear prediction of cardiac late potentials

Late potentials in patients with coronary artery disease and sustained ventricular arrhythmias have been detected using time and frequency domain methods and recently in the joint time-frequency domain using the Wigner-Ville distribution. Since electrocardiogram (ECG) signals are multicomponent and broadband, the smoothed Wigner distribution is used to represent the ECG signals in the time-frequency domain. Based on the assumption that late potentials are uncorrelated with the surrounding ECG, linear prediction is used as a tool to enhance the late potentials in a least-squares sense. Great differences between the three patient classes can be seen in the smoothed Wigner distribution