[The significance of spontaneous variability in ventricular extrasystole in the evaluation of the effectiveness of therapy of ventricular extrasystole]. / Význam spontánnej variability komorovej extrasystólie pri hodnotení úcinosti liecby komorových extrasystólií.

In a mixed population of 104 ambulatory patients the authors assessed, based on 24-hour Holter monitoring, the spontaneous variability of ventricular extrasystoles within one-, two-, three-, four-, six-, eight- and twelve-hour intervals. As significant they evaluated a decline of the frequency of ventricular extrasystoles by more than 90% during the subsequent period of time. The magnitude of variability is influenced substantially more by the frequency of extrasystoles than by the period of monitoring. This fact is not generally accepted so far, although it was already described in 1978. It is probable that this fact participates in a significant way in the difference of values of spontaneous variability reported by different departments.