This ECG has ventricular pacing as seen by pacemaker spikes prior to each QRS complex, however has a more right bundle branch appearance. This is a biventricular pacemaker which has one lead in ...

Also note the pacing spikes on this ECG are quite large. Older devices that were unipolar appeared like this, however most current pacemakers have quite small pacemaker spikes on the ECG which can ...

during the same burst of right atrial pacing as in Figure 1. H = His bundle spike. Other abbreviations as in Figure 1. Ladder diagram example explaining the postulated mechanisms for the EKG ...