[A mechanism of terminating atrial flutter using programmed atrial stimulation]

The analysis of 1168 programmed stimulations (PS) from 30 studies during the last 20 years has shown that the termination of atrial flutter (a-flut) by means of PS directly resulted in sinusrhythm (SR) in 45% of cases. SR following a brief atrial fibrillation (a-fib) occurs in 20% of cases, while in 30% of cases a permanent a-fib results. Our study of 107 cases of a-flut have confirmed these results. The technique of stimulation and the atrial rate show no difference in how the result groups are distributed. It seems as if the maximal pacing rates applied play an important role in whether SR or a-fib is brought about. Permanent a-fib was more often the result of a high pacing rate. A comparable relationship is valid for the difference between the a-flut rate and the maximal pacing rate employed. There was no relation to the pacing rate whether SR was achieved directly or after a brief a-fib. The pacing rate and the difference was equally great when the a-flut was terminated into both groups, but significantly less then when permanent a-fib was triggered. There are three possible mechanisms which may be used to explain how an interaction between programmed stimulation and reentry could take place.