Click on image to view larger version.

Figure 2 Stored electrogram and marker channel (Medtronic 7202) of spontaneous ventricular flutter (300–350 bpm) that was terminated with a 34-J shock. Of note, no sustained ventricular arrhythmia was inducible with up to three extrastimuli at programmed stimulation in this patient with IDC who presented with asymptomatic nonsustained VT on Holter. Abbreviations used in the marker channel: CD = cardioversion pulse; FD = fibrillation detection; FS = fibrillation sense; VS = normal sense.