Patent ID: 6979297
Filing Date: 2005-12-27
Classification: A61B

Abstract:
1. A method for clarifying a subject's collected ECG waveform for analysis by first effectively removing a recognized, embedded influence over certain characteristics of that waveform which exists by virtue of the physiologic presence, in the subject's heart, of a particular ECG confounder, said method comprising creating a reference ECG waveform model which possesses the characteristics of an ECG waveform that is influenced by the presence of the particular confounder, linking the model to an ECG purge algorithm which, in cooperation with the model, can be applied to such a subject's collected ECG waveform to remove the influence of the confounder, and applying the linked model and purge algorithm to such a collected ECG waveform, thus to produce a purge-processed ECG waveform that lacks the influence of the selected confounder, wherein said creating comprises quantitative modeling of ST abnormalities due to the presence of Left Bundle Branch Block (LBBB) within the traditional 12-lead resting ECG, and said modeling includes (a) identifying ECG leads for which LBBB induced ST deviation (modST) will be estimated, (b) for each such lead being considered, measuring the largest positive and the largest negative voltage deflections (PosMax, NegMax), (c) calculating the actual ST deviation (STdev) at the J+20 ms point, (d) calculating the estimated LBBB induced deviation: (estST): estST=−(NegMax-STdev)+(PosMas−STdev)/10, and (e) establishing, lead-by-lead, the direct current (DC) offset constant value component for use in a normalizing equation.