As noted above, the precordial leads are unreliable, compromising by their inclusion calculations deriving from the set of 12 ECG leads. It appears, therefore, that using sums of data from the six ...

Figure 1 displays surface electrocardiogram (ECG) lead I and three intracardiac electrograms: bipolar atrial electrogram, integrated bipolar ventricular electrogram (obtained from the RV tip to RV ...