Analysis of cardiac late potentials using the Wigner-Ville distribution

High-frequency low-amplitude signals have been found in signal averaged surface electrocardiograms (ECGs) of patients with coronary artery disease and sustained ventricular arrhythmias. These signals, termed late potentials (LPs), occur in the terminal phases of the ventricular depolarization and are important in patient prognosis. In the past, ECGs have been examined in either the time or the frequency domain in order to obtain parameters that will allow the detection of late potentials. None of the existing methods consider the nonstationarity of the late potentials in their detection. The authors propose the use of the Wigner-Ville distribution for detecting late potentials in the time-frequency domain