Figure 7:

Native signal undersensing from cardiac contractility modulation (CCM) before ventricular fibrillation (VF) induction. The single-chamber defibrillator has a non-programmable ventricular blanking period. The red arrows indicate the undersensed native signals on the near-field ventricular electrogram. The automatic gain function results in only CCM signal sensing by the defibrillator initially (black arrows). CCM therapy is immediately inhibited with induction and remains inhibited during VF. VF detection is not delayed nor is VF undersensed.