Atrioventricular node pathways and the rr interval histogram in patients with atrial fibrillation

Abstract

The aim - to examine several pts before and after restoration of sinus rhythm (SR) by radiofrequency ablation and determine the presence of multiple AV nodel pathways in pts with permanent atrial fibrilation (PAF). Material and methods 64 pts with PAF were involved in study. SR was restored for 19 pts by radiofrequency catheter ablation. For each pts in this group, 500 RR intervals were recorded at rest, during orthostasis, and during exercises. The number of peaks on the RR interval histogram (RR IH) was determined. The test was repeated next day after successful radiofrequency ablation. Results. The RR IH analysis in pts with PAF showed that there were three types of RR interval histograms: unimodal, bimodal and polymodal. A single peak RRIH was found in 45% of pts, 40% of pts had two peaks, and 15% of pts had three or more peaks. After ablation, ventricular rate, heart rate variability, and/or number of peaks decreased in all pts. This suggested the present of multiple AV nodal pathways during atrial fibrilation. According to our data, this method may prove to be useful in selecting pts with PAF who are considered as data, this method may prove to be useful in selecting pts with PAF who are consiudered as candidates for radiofrequency modification of AV nodal conductive as opposed to AV nodal ablation. Conclusions: The computer-based RR IHanalysis method in patients with atrial fibrilation is a non-invasive method useful for investigation of AV function, morphology, or clinical aspects.