Figure 6.
Circadian rhythm in bradyarrhythmias and atrial tachycardia/flutter and atrial fibrillation (AT/AF). A: Circadian variation in asystolic pauses throughout 24 hours in 19 veteran athletes (human). Solid line shows the distribution in a veteran athlete with 846 pauses in 24 hours, which only occurred between the hours of 01:00 and 08:00. From Northcote et al,65 with permission. B: Circadian variation of bradyarrhythmia episodes and duration of heart block episodes in the healthy rat (bradyarrhythmia episodes analyzed for 94 days in 14 rats). From Otsuka et al,39 with permission. C: Circadian rhythm of AT/AF onset stratified by frequency of AT/AF events. Data from 72 (1–3 AT/AF events per hour), 72 (4–9 AT/AF events per hour), 69 (10–50 AT/AF events per hour), and 7 (51–119 AT/AF events per h) patients. From Shusterman et al,42 with permission.