In a substantial number of patients, AF recurs after successful
electrical cardioversion. The purpose of this study was to investigate
if the atrial arrhythmias recorded immediately after cardioversion are
associated with the risk of recurrence of the arrhythmia and to compare
the prognostic significance of this parameter with that of other
established risk factors. In a series of 71 patients, the risk factors
for recurrence of AF during the first year after successful electrical
cardioversion were analyzed. A new parameter that was investigated was
the frequency of atrial premature beats and the presence of runs of
supraventricular tachycardia in the Holter recording started immediately
after the cardioversion. Age, left atrial size, left ventricular
systolic function, duration of the arrhythmia before cardioversion,
underlying cardiac disease, or medication taken were not found to be
predictive of recurrence of the arrhythmia. However, the natural
logarithm of the number of atrial premature complexes per hour of the
Holter recording in the 37 patients in whom AF recurred was higher
compared to that of the 34 patients who maintained sinus rhythm (P <
0.0005). The same was true if only the first 6 hours of the recording
were analyzed (P < 0.0005). There was a trend for more frequent
arrhythmia recurrence if runs of supraventricular tachycardia were
present. The finding of > 10 atrial premature complexes per hour in the
recording had a relative risk of 2.57 (1.51-4.37), a positive predictive
accuracy of 76.5%, and a negative predictive accuracy of 70.3% for
subsequent arrhythmia recurrence. We can conclude that frequent (>
10/hour) atrial premature complexes in the Holter recording after
electrical cardioversion for AF is a significant risk factor for
recurrence of the arrhythmia
