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Figure 4 Circadian Variations of HASDA

We manually analyzed the number of high amplitude spike discharge activity (HASDA) episodes at baseline (1 day before commencement of rapid pacing) and during congestive heart failure (CHF) (1 day after cessation of pacing). The data of all dogs were then pooled together. There were circadian variations of HASDA, with peak incidence 7:00 AM to 8:00 AM.