Key result
Frequent premature atrial contractions (≥720/day) showed a circadian variation peaking at 3 pm, but no specific time interval of the day was more predictive of incident atrial fibrillation.
Why the study?
Does the circadian variation of premature atrial contractions predict the incidence of atrial fibrillation in a community-based population?
Cohort (n=638)
Does the circadian variation of premature atrial contractions predict the incidence of atrial fibrillation in a community-based population?
While frequent premature atrial contractions exhibit a circadian rhythm peaking in the afternoon, the specific timing of PACs does not provide additional predictive value for the future development of atrial fibrillation.
Timing of frequent PACs adds no independent AF risk after adjustment; leaves open whether circadian factors influence arrhythmia onset.
AIMS: The aim of the study was to assess a possible circadian variation of premature atrial contractions (PACs) in a community-based population and to determine if the daily variation could be used to assess a more vulnerable period of PACs in predicting later incidence of atrial fibrillation (AF). METHODS AND RESULTS: We studied 638 subjects between the ages of 55 and 75 years from the Copenhagen Holter Study who underwent up to 48 h electrocardiogram recording. Follow-up on cardiovascular endpoints was performed in 2013 with a median follow-up time of 14.4 years. According to previous studies, two subgroups were studied based on a cut-off point of ≥720 PACs/day termed frequent PACs (n = 66) and not frequent PACs with <720 PACs/day (n = 572). Based on median values, a circadian rhythm could not be demonstrated in the population as a whole and the group without frequent PACs. However, a circadian variation was observed in the group with frequent PACs, who had the fewest PACs/h during the night with a nadir at 6 am and then reaching a peak value in the afternoon at 3 pm. Runs of PACs in all subjects showed a similar circadian variation. Both PACs/h and runs of PACs seemed to follow the daily variation in heart rate. After adjusting for relevant risk factors, the risk of AF was equal in all time intervals throughout the day. CONCLUSION: Premature atrial contractions showed a circadian variation in subjects with frequent PACs. No specific time interval of the day was more predictive of AF than others.
No takes yet. Share an insight, caveat, or question.
Larsen et al. (2015) conducted a cohort in Premature atrial contractions (n=638). Frequent premature atrial contractions (≥720 PACs/day) vs. Not frequent PACs (<720 PACs/day) was evaluated on Incidence of atrial fibrillation. Frequent premature atrial contractions (≥720/day) showed a circadian variation peaking at 3 pm, but no specific time interval of the day was more predictive of incident atrial fibrillation.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: