The Ventricular Late Potentials (VLP) are low-amplitude (< 1 microVolt) electric signals detected on the thoracic surface which appear at the end of the QRS. These signals represent a delay in the conduction of the depolarizing electric impulse due to the presence of ill or infarcted ventricular myocardial tissue. The GBI-3S Recorder records the high resolution data, and this program is used for the analysis and graphic representation of such data.