Detecting ventricular late potentials using the continuous wavelet transform

The detection of Ventricular Late Potential (VLP) activity in the terminal region of the QRS complex provides an indicator of a patient´s susceptibility to Ventricular Tachycardia. In this study the Continuous Wavelet Transform was used to form a time-scale plot of the High Resolution ECG. Visual inspection of this plot reveals that at the smaller scales (higher frequencies) there is a greater level of fractionation present in patients with documented VLP activity than those without. The authors propose a novel method of detecting VLP activity by quantifying the degree of fractionation present. Evaluation of the method on 60 post-MI patients produced promising results. Preliminary investigations also suggest that the method can be used successfully with far fewer ECG cycles than required by standard time domain methods