Y. Tsuchioka et al., THE ROLE OF THE ACCESSORY PATHWAY IN THE ONSET OF ATRIAL-FIBRILLATIONIN WOLFF-PARKINSON-WHITE SYNDROME, Japanese Circulation Journal, 58(2), 1994, pp. 95-99
To determine the role of the accessory pathway in the pathogenesis of
atrial fibrillation, we compared electrophysiological findings in 17 p
atients (44.7+/-10.2 years) with a history of atrial fibrillation befo
re and after surgical ablation of the accessory pathway. The PA interv
al was shortened, and the atrial refractory periods and the potential
minimal wavelength of an atrial impulse (FRP(A)/PA) were significantly
increased, after surgery. Fragmented atrial activity (an increase of
150% or more in the duration of the high right atrial electrogram) was
observed in 80% of the patients before surgery and in 25% after surge
ry. Its zone was significantly decreased after surgery. Repetitive atr
ial firing was defined as the occurrence of 3 or more successive atria
l electrograms induced by a premature stimulation. This was observed i
n 60% of the patients before surgery, but in none after surgery. Atria
l fibrillation was induced in 16 patients during the preoperative stud
y, but in only 1 patient postoperatively. In conclusion, these results
suggest that accessory pathways affect atrial vulnerability and play
an important role in the onset of atrial fibrillation in WPW syndrome.