Figure 2A. – Correlation of QRS variation and normal values for a patient with intact intraventricular conduction (leads II and V6). Left: Conventional ECG traces. Center: overlapping QRS segments (D2 QRS and V6 QRS). Right: Cross-correlation analysis of leads II and V6. The QRS peaks coincide and the maximum cross-correlation signal is at time zero (CorS = 0). CorS: cross-correlation offset (ms). CorW: cross-correlation width (ms), CorA: cross-correlation amplitude (mV), AII: area under lead D2, aV6: area under lead V6. Adapted from Bonomini et al.²².