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Figure 1 Nonthoracic neuromuscular incapacitating device (NID) discharge. This figure illustrates a typical episode of NID discharge in the nonthoracic vector configuration, which does not result in the stimulation of the myocardium. The surface electrocardiogram lead 1, intracardiac electrograms from the coronary sinus (CS) and the right ventricular (RV) apex, and blood pressure (BP) recording from the MILLAR catheter in the descending aorta are shown. (A) The rhythm before the NID discharge. This shows regular rhythm. It is very similar to the rhythm and rate in (C). Interestingly, in B, the surface electrocardiograms are corrupted by the high voltage discharge. However, the intracardiac electrograms, as shown in D and E, do not show any significant change in rate morphology and are not phase locked (no temporal relationship between stimuli and the electrogram) with the NID discharge. Note also the lack of perturbation of blood pressure during the discharge. The rate and morphology are not significantly different between D and E, further illustrating the lack of myocardial stimulation.