Effects of Dantrolene on Arrhythmogenicity in Isolated Regional Ischemia-Reperfusion Rabbit Hearts with or without Pacing-Induced Heart Failure

Figure 6

VF induction and spontaneous termination during dantrolene administration in a non-HF heart. (a) and (b) tracings corresponding to the points labeled in panel (c) during VF induction and VF termination, respectively. The red arrows indicate wavefront propagation, and the white lines indicate conduction block. L: long; S: short. (c) Isochronal maps corresponding to the period labeled in panel (a) showing CV alternans followed by conduction block and VF initiation. The white lines indicate functional conduction block. (d) Frame shots corresponding to the period labeled in panel. (b) The white lines indicate lines of functional conduction block, and the white arrow indicates focal breakthrough. (e) APD difference maps showing SDA induction. The black and red arrows indicate nodal lines. (f) The dominant frequency (DF) maps of induced VF at baseline (A) and after dantrolene infusion (B). SR: sinus rhythm.

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