Atrial ectopics preceding paroxysmal atrial fibrillation were significantly more frequent (5.07 vs 3.60 min-1, P=5x10^-24) and more premature (0.56 vs 0.60, P=2x10^-73) than those remote from episodes.
Observational (n=60)
Are atrial ectopics preceding paroxysmal atrial fibrillation more frequent and premature than those occurring remote from episodes?
Paroxysmal atrial fibrillation is often preceded by more frequent and premature atrial ectopics, suggesting Holter monitoring may help identify patients with focally mediated AF suitable for electrophysiological assessment.
Absolute Event Rate: 5.07% vs 3.6%
p-value: p=5 x 10(-24)
AIMS: To characterize the nature and timing of atrial ectopics preceding clinical episodes of paroxysmal atrial fibrillation. METHODS AND RESULTS: Holter recordings (n= 177, 60 patients, 58% male, mean age 61.7 +/- 11.5 years) were performed on patients with paroxysmal atrial fibrillation. These were subjected to standard analysis and recordings containing atrial fibrillation episodes suitable for analysis were identified (n = 74). Beat interval files differentiating sinus rhythm from atrial fibrillation were generated and atrial ectopics were identified. Atrial ectopics preceding atrial fibrillation were found to be more frequent (5.07 +/- 7.39 min(-1)) and more premature (ratio of coupling interval to that of surrounding sinus cycles = 0.56 +/- 0.08) compared to ectopics occurring remote from atrial fibrillation episodes (frequency = 3.60 +/- 7.32 min(-1) P = 5 x 10(-24), prematurity ratio = 0.60 +/- 0.10, P = 2 x 10(-73)). Atrial ectopic coupling interval frequency histograms were generated and analysed visually and by an automated statistically based test. Many ectopics were seen to occur at one coupling interval in 27 recordings (in eight this occurred only preceding atrial fibrillation onset, while in a further 19 cases this was also seen remote from atrial fibrillation onset). Overall 45% of ectopics preceding atrial fibrillation episodes occurred in isolation, 13% as part of a bigeminal rhythm, 22% as couplets and 20% as runs. This pattern did not differ from that seen remote from atrial fibrillation episodes. CONCLUSION: Paroxysmal atrial fibrillation is preceded by ectopics of a fixed coupling interval in a significant proportion of patients. If, as seems likely, this is a marker of 'focally mediated' atrial fibrillation, then Holter techniques may provide a useful screening tool with which to identify patients suitable for fuller electrophysiological assessment.
Johan Waktare (Thu,) conducted a observational in Paroxysmal atrial fibrillation (n=60). Atrial ectopics preceding atrial fibrillation vs. Atrial ectopics remote from atrial fibrillation episodes was evaluated on Frequency of atrial ectopics (min-1) (p=5 x 10(-24)). Atrial ectopics preceding paroxysmal atrial fibrillation were significantly more frequent (5.07 vs 3.60 min-1, P=5x10^-24) and more premature (0.56 vs 0.60, P=2x10^-73) than those remote from episodes.