[Long-term reproducibility of programmed atrial stimulation].

Programmed atrial stimulation is a technique increasingly used to assess different pathologies but the reproducibility of the results is totally unknown. The aim of this study was to determine its reproducibility. Two electrophysiological studies were undertaken without antiarrhythmic therapy in an interval of one to three months (average 18 months) in 48 patients. The programmed atrial stimulation used 1 and 2 extrastimuli delivered in sinus rhythm and then three paced rhythms (sinus cycle -10%, 600 ms, 400 ms). Twenty-one patients had documented atrial arrhythmias (atrial fibrillation n = 13, flutter n = 3 or tachycardia n = 5) (group 1) and the 27 other patients had no spontaneous arrhythmias (group II). In group I, clinical tachycardial was reproduced in 18 patients during the initial stimulation procedure. During the second investigation, 17 remained inducible and in the 3 in whom stimulation was negative, it remained so in 2 of the cases. The reproducibility was therefore 90%. In group II, 12 patients had inducible sustained (for over 1 minute) tachycardia during the first procedure (44%) but this only remained inducible in 6 patients. In the other 15 subjects, stimulation was negative during the first procedure but 7 of them had inducible tachycardial during the second procedure. The reproducibility of the technique was therefore only of 52%. The authors conclude that the reproducibility of programmed atrial stimulation in patients with documented spontaneous paroxysmal arrhythmias is excellent. However, the reproducibility is mediocre in subjects without spontaneous arrhythmias and the induction of tachycardial in this group of patients should be interpreted with caution given the variability of the response to programmed atrial stimulation.