Figure 5

Low DC added to the magnetic pulses and high vs. low duty cycle.

Previous experiment (presented in Fig. 4) was repeated with different wave forms. In (a) we added low DC (~5 A) to the AC waveform. In (b) we switched from high (80%) to low (20%) duty cycles (see more detailed information of the pacing in B in Fig. 4 in supplementary information). The blue line indicates the arterial pressure (AP) and the red line indicates the current through the electromagnet coil. Plus (+) signs indicate heart beats that are synchronized with the magnetic pulses. Note the absence of effective pacing using both protocols, but effective transient pacing after switching to low duty cycle without DC, indicating that both protocols retained the IMPs in the RV (see text for more details). The number of consecutive synchronized heart beats were counted and the mean + SEM for each group is plotted (c). Bars are SEM, *p < 0.05.