de s r a

ectopics preceding clinical episodes of paroxysmal atrial fibrillation. Methods and Results Holter recordings (n=177, 60 patients, 58 % male, mean age 61·711·5 years) were performed on patients with paroxysmal atrial fibrillation. These were subjected to standard analysis and recordings 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. trigger the onset of atrial fibrillation, which is then [9,10]Paroxysmal atrial fibrillation is associated with numer-ous predisposing conditions, such as hypertension, previous myocardial infarction, and congestive cardiac failure[1]. However, up to half of patients suffering from paroxysmal atrial fibrillation have no apparent under-lying cardiac pathology, as do 20 % of those with persist-ent or permanent atrial fibrillation[2]. Therefore, primary arrhythmic mechanisms are probably important in the genesis of atrial fibrillation. maintained by random multiple wavelet re-entry. Although some patients with atrial fibrillation parox-ysms have an underlying focal atrial tachycardia[11,12] or other initiating tachycardia[3–5], systematic evaluation suggests such cases are not too frequent[13]. The auto-nomic nervous system plays a role in atrial fibrillation initiation[14], with some patients suffering atrial fibril-lation episodes at times of high vagal or, more rarely, high adrenergic tone. While such patients are seen in clinical practice, systematic evaluation reveals that consistent patterns of tachycardic or bradycardic onsetThe role of atrial ectopic atrial fi