Characterizing cardiac late potentials with an RMS function

Late potentials can be viewed as a cardiac source that originates from a diseased region of the ventricles but is added to the other ventricular sources which produce the QRS complex and ST segment potentials. Various time-domain features have been extracted from these high-resolution ECGs (electrocardiograms) and are used to identify patients at high risk for ventricular tachycardia, particularly following myocardial infarction. Based on results using 15 normal subjects and 11 patients with ventricular tachycardia, it was found that the maximum value of the RMS function, V(T), and time of maximum V(T) were significantly different for these selected groups and were independent of high-pass filtering. Thus, this more complete description of signal power can provide a better means of discriminating normal and abnormal measures of late potentials.<>