Figure 3.
Chloroquine terminates cholinergic AF in the sheep heart. A) First panel: image of the left atrial appendage with the 20-unipole catheter stitched on the epicardial surface. Second panel: DF map during AF, before chloroquine (DFmax=18.5 Hz). Third panel: DF map at 4 min after chloroquine (DFmax=11 Hz). Fourth panel: just before termination (DFmax=8.5 Hz). Numbers in red relate to panel C (see below). One-second, single-pixel recordings are shown under each DF map. B) Plots of the 20 electrograms in a representative example just before chloroquine terminated AF and restored sinus rhythm. C) Plot of frequency calculated from each of the 20 unipolar atrial electrograms in one experiment. Frequency was measured every minute before chloroquine, and every 0.5 min after chloroquine. Numbers in red indicate the time in the experiment at which the DF maps in panel A were taken. D) Time course of normalized frequency before and during chloroquine treatment for the 20 electrograms in the 5 sheep. Each symbol represents an experiment.