The prognostic significance of atrial arrhythmias recorded early after cardioversion for atrial fibrillation

In a substantial number of patients, AF recurs after successful electrical cardioversion. The purpose of this study was to investigate if the atrial a rrhythmias recorded immediately after cardioversion are associated with the risk of recurrence of the arrhythmia and to compare the prognostic signifi cance of this parameter with that of other established risk factors. In a s eries of 71 patients, the risk factors for recurrence of AF during the firs t year after successful electrical cardioversion were analyzed. A new param eter that was investigated was the frequency of atrial premature beats and the presence of runs of supraventricular tachycardia in the Holter recordin g started immediately after the cardioversion. Age, left atrial size, left ventricular systolic function, duration of the arrhythmia before cardiovers ion, underlying cardiac disease, or medication taken were not found to be p redictive of recurrence of the arrhythmia. However, the natural logarithm o f 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 w as a trend for more frequent arrhythmia recurrence if runs of supraventricu lar tachycardia were present. The finding of > 10 atrial premature complexe s per hour in the recording had a relative risk of 2.57 (1.51-4.37), a posi tive 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 electrica l cardioversion for AF is a significant risk factor for recurrence of the a rrhythmia.